diff options
| author | Ingo Molnar <mingo@kernel.org> | 2018-02-06 21:12:31 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-06 21:12:31 +0100 |
| commit | 82845079160817cc6ac64e5321bbd935e0a47b3a (patch) | |
| tree | 0886d1d52428e9db14536cae4b37db896e7c360a /kernel | |
| parent | 32e839dda3ba576943365f0f5817ce5c843137dc (diff) | |
| parent | 68c5735eaa5e680e701c9a2d1e3c7880bdf5ab66 (diff) | |
| download | op-kernel-dev-82845079160817cc6ac64e5321bbd935e0a47b3a.zip op-kernel-dev-82845079160817cc6ac64e5321bbd935e0a47b3a.tar.gz | |
Merge branch 'linus' into sched/urgent, to resolve conflicts
Conflicts:
arch/arm64/kernel/entry.S
arch/x86/Kconfig
include/linux/sched/mm.h
kernel/fork.c
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
58 files changed, 4082 insertions, 1225 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 172d151d..f85ae5d 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -81,6 +81,7 @@ obj-$(CONFIG_AUDIT_TREE) += audit_tree.o obj-$(CONFIG_GCOV_KERNEL) += gcov/ obj-$(CONFIG_KCOV) += kcov.o obj-$(CONFIG_KPROBES) += kprobes.o +obj-$(CONFIG_FAIL_FUNCTION) += fail_function.o obj-$(CONFIG_KGDB) += debug/ obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index e691da0..a713fd2 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -9,9 +9,11 @@ obj-$(CONFIG_BPF_SYSCALL) += devmap.o obj-$(CONFIG_BPF_SYSCALL) += cpumap.o obj-$(CONFIG_BPF_SYSCALL) += offload.o ifeq ($(CONFIG_STREAM_PARSER),y) +ifeq ($(CONFIG_INET),y) obj-$(CONFIG_BPF_SYSCALL) += sockmap.o endif endif +endif ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_BPF_SYSCALL) += stackmap.o endif diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index ab94d30..b1f6648 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -49,27 +49,35 @@ static int bpf_array_alloc_percpu(struct bpf_array *array) } /* Called from syscall */ -static struct bpf_map *array_map_alloc(union bpf_attr *attr) +static int array_map_alloc_check(union bpf_attr *attr) { bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; int numa_node = bpf_map_attr_numa_node(attr); - u32 elem_size, index_mask, max_entries; - bool unpriv = !capable(CAP_SYS_ADMIN); - struct bpf_array *array; - u64 array_size, mask64; /* check sanity of attributes */ if (attr->max_entries == 0 || attr->key_size != 4 || attr->value_size == 0 || attr->map_flags & ~ARRAY_CREATE_FLAG_MASK || (percpu && numa_node != NUMA_NO_NODE)) - return ERR_PTR(-EINVAL); + return -EINVAL; if (attr->value_size > KMALLOC_MAX_SIZE) /* if value_size is bigger, the user space won't be able to * access the elements. */ - return ERR_PTR(-E2BIG); + return -E2BIG; + + return 0; +} + +static struct bpf_map *array_map_alloc(union bpf_attr *attr) +{ + bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; + int numa_node = bpf_map_attr_numa_node(attr); + u32 elem_size, index_mask, max_entries; + bool unpriv = !capable(CAP_SYS_ADMIN); + struct bpf_array *array; + u64 array_size, mask64; elem_size = round_up(attr->value_size, 8); @@ -112,12 +120,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) array->map.unpriv_array = unpriv; /* copy mandatory map attributes */ - array->map.map_type = attr->map_type; - array->map.key_size = attr->key_size; - array->map.value_size = attr->value_size; - array->map.max_entries = attr->max_entries; - array->map.map_flags = attr->map_flags; - array->map.numa_node = numa_node; + bpf_map_init_from_attr(&array->map, attr); array->elem_size = elem_size; if (!percpu) @@ -327,6 +330,7 @@ static void array_map_free(struct bpf_map *map) } const struct bpf_map_ops array_map_ops = { + .map_alloc_check = array_map_alloc_check, .map_alloc = array_map_alloc, .map_free = array_map_free, .map_get_next_key = array_map_get_next_key, @@ -337,6 +341,7 @@ const struct bpf_map_ops array_map_ops = { }; const struct bpf_map_ops percpu_array_map_ops = { + .map_alloc_check = array_map_alloc_check, .map_alloc = array_map_alloc, .map_free = array_map_free, .map_get_next_key = array_map_get_next_key, @@ -345,12 +350,12 @@ const struct bpf_map_ops percpu_array_map_ops = { .map_delete_elem = array_map_delete_elem, }; -static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr) +static int fd_array_map_alloc_check(union bpf_attr *attr) { /* only file descriptors can be stored in this type of map */ if (attr->value_size != sizeof(u32)) - return ERR_PTR(-EINVAL); - return array_map_alloc(attr); + return -EINVAL; + return array_map_alloc_check(attr); } static void fd_array_map_free(struct bpf_map *map) @@ -474,7 +479,8 @@ void bpf_fd_array_map_clear(struct bpf_map *map) } const struct bpf_map_ops prog_array_map_ops = { - .map_alloc = fd_array_map_alloc, + .map_alloc_check = fd_array_map_alloc_check, + .map_alloc = array_map_alloc, .map_free = fd_array_map_free, .map_get_next_key = array_map_get_next_key, .map_lookup_elem = fd_array_map_lookup_elem, @@ -561,7 +567,8 @@ static void perf_event_fd_array_release(struct bpf_map *map, } const struct bpf_map_ops perf_event_array_map_ops = { - .map_alloc = fd_array_map_alloc, + .map_alloc_check = fd_array_map_alloc_check, + .map_alloc = array_map_alloc, .map_free = fd_array_map_free, .map_get_next_key = array_map_get_next_key, .map_lookup_elem = fd_array_map_lookup_elem, @@ -592,7 +599,8 @@ static void cgroup_fd_array_free(struct bpf_map *map) } const struct bpf_map_ops cgroup_array_map_ops = { - .map_alloc = fd_array_map_alloc, + .map_alloc_check = fd_array_map_alloc_check, + .map_alloc = array_map_alloc, .map_free = cgroup_fd_array_free, .map_get_next_key = array_map_get_next_key, .map_lookup_elem = fd_array_map_lookup_elem, @@ -610,7 +618,7 @@ static struct bpf_map *array_of_map_alloc(union bpf_attr *attr) if (IS_ERR(inner_map_meta)) return inner_map_meta; - map = fd_array_map_alloc(attr); + map = array_map_alloc(attr); if (IS_ERR(map)) { bpf_map_meta_free(inner_map_meta); return map; @@ -673,6 +681,7 @@ static u32 array_of_map_gen_lookup(struct bpf_map *map, } const struct bpf_map_ops array_of_maps_map_ops = { + .map_alloc_check = fd_array_map_alloc_check, .map_alloc = array_of_map_alloc, .map_free = array_of_map_free, .map_get_next_key = array_map_get_next_key, diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index b789ab7..c1c0b60 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -568,6 +568,8 @@ static bool cgroup_dev_is_valid_access(int off, int size, enum bpf_access_type type, struct bpf_insn_access_aux *info) { + const int size_default = sizeof(__u32); + if (type == BPF_WRITE) return false; @@ -576,8 +578,17 @@ static bool cgroup_dev_is_valid_access(int off, int size, /* The verifier guarantees that size > 0. */ if (off % size != 0) return false; - if (size != sizeof(__u32)) - return false; + + switch (off) { + case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type): + bpf_ctx_record_field_size(info, size_default); + if (!bpf_ctx_narrow_access_ok(off, size, size_default)) + return false; + break; + default: + if (size != size_default) + return false; + } return true; } diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 7949e8b..5f35f93 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -94,6 +94,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags) fp->pages = size / PAGE_SIZE; fp->aux = aux; fp->aux->prog = fp; + fp->jit_requested = ebpf_jit_enabled(); INIT_LIST_HEAD_RCU(&fp->aux->ksym_lnode); @@ -217,30 +218,40 @@ int bpf_prog_calc_tag(struct bpf_prog *fp) return 0; } -static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn) -{ - return BPF_CLASS(insn->code) == BPF_JMP && - /* Call and Exit are both special jumps with no - * target inside the BPF instruction image. - */ - BPF_OP(insn->code) != BPF_CALL && - BPF_OP(insn->code) != BPF_EXIT; -} - static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta) { struct bpf_insn *insn = prog->insnsi; u32 i, insn_cnt = prog->len; + bool pseudo_call; + u8 code; + int off; for (i = 0; i < insn_cnt; i++, insn++) { - if (!bpf_is_jmp_and_has_target(insn)) + code = insn->code; + if (BPF_CLASS(code) != BPF_JMP) continue; + if (BPF_OP(code) == BPF_EXIT) + continue; + if (BPF_OP(code) == BPF_CALL) { + if (insn->src_reg == BPF_PSEUDO_CALL) + pseudo_call = true; + else + continue; + } else { + pseudo_call = false; + } + off = pseudo_call ? insn->imm : insn->off; /* Adjust offset of jmps if we cross boundaries. */ - if (i < pos && i + insn->off + 1 > pos) - insn->off += delta; - else if (i > pos + delta && i + insn->off + 1 <= pos + delta) - insn->off -= delta; + if (i < pos && i + off + 1 > pos) + off += delta; + else if (i > pos + delta && i + off + 1 <= pos + delta) + off -= delta; + + if (pseudo_call) + insn->imm = off; + else + insn->off = off; } } @@ -289,6 +300,11 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, } #ifdef CONFIG_BPF_JIT +/* All BPF JIT sysctl knobs here. */ +int bpf_jit_enable __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON); +int bpf_jit_harden __read_mostly; +int bpf_jit_kallsyms __read_mostly; + static __always_inline void bpf_get_prog_addr_region(const struct bpf_prog *prog, unsigned long *symbol_start, @@ -370,8 +386,6 @@ static DEFINE_SPINLOCK(bpf_lock); static LIST_HEAD(bpf_kallsyms); static struct latch_tree_root bpf_tree __cacheline_aligned; -int bpf_jit_kallsyms __read_mostly; - static void bpf_prog_ksym_node_add(struct bpf_prog_aux *aux) { WARN_ON_ONCE(!list_empty(&aux->ksym_lnode)); @@ -552,8 +566,6 @@ void __weak bpf_jit_free(struct bpf_prog *fp) bpf_prog_unlock_free(fp); } -int bpf_jit_harden __read_mostly; - static int bpf_jit_blind_insn(const struct bpf_insn *from, const struct bpf_insn *aux, struct bpf_insn *to_buff) @@ -711,7 +723,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) struct bpf_insn *insn; int i, rewritten; - if (!bpf_jit_blinding_enabled()) + if (!bpf_jit_blinding_enabled(prog) || prog->blinded) return prog; clone = bpf_prog_clone_create(prog, GFP_USER); @@ -753,13 +765,16 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) i += insn_delta; } + clone->blinded = 1; return clone; } #endif /* CONFIG_BPF_JIT */ /* Base function for offset calculation. Needs to go into .text section, * therefore keeping it non-static as well; will also be used by JITs - * anyway later on, so do not let the compiler omit it. + * anyway later on, so do not let the compiler omit it. This also needs + * to go into kallsyms for correlation from e.g. bpftool, so naming + * must not change. */ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { @@ -767,6 +782,137 @@ noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) } EXPORT_SYMBOL_GPL(__bpf_call_base); +/* All UAPI available opcodes. */ +#define BPF_INSN_MAP(INSN_2, INSN_3) \ + /* 32 bit ALU operations. */ \ + /* Register based. */ \ + INSN_3(ALU, ADD, X), \ + INSN_3(ALU, SUB, X), \ + INSN_3(ALU, AND, X), \ + INSN_3(ALU, OR, X), \ + INSN_3(ALU, LSH, X), \ + INSN_3(ALU, RSH, X), \ + INSN_3(ALU, XOR, X), \ + INSN_3(ALU, MUL, X), \ + INSN_3(ALU, MOV, X), \ + INSN_3(ALU, DIV, X), \ + INSN_3(ALU, MOD, X), \ + INSN_2(ALU, NEG), \ + INSN_3(ALU, END, TO_BE), \ + INSN_3(ALU, END, TO_LE), \ + /* Immediate based. */ \ + INSN_3(ALU, ADD, K), \ + INSN_3(ALU, SUB, K), \ + INSN_3(ALU, AND, K), \ + INSN_3(ALU, OR, K), \ + INSN_3(ALU, LSH, K), \ + INSN_3(ALU, RSH, K), \ + INSN_3(ALU, XOR, K), \ + INSN_3(ALU, MUL, K), \ + INSN_3(ALU, MOV, K), \ + INSN_3(ALU, DIV, K), \ + INSN_3(ALU, MOD, K), \ + /* 64 bit ALU operations. */ \ + /* Register based. */ \ + INSN_3(ALU64, ADD, X), \ + INSN_3(ALU64, SUB, X), \ + INSN_3(ALU64, AND, X), \ + INSN_3(ALU64, OR, X), \ + INSN_3(ALU64, LSH, X), \ + INSN_3(ALU64, RSH, X), \ + INSN_3(ALU64, XOR, X), \ + INSN_3(ALU64, MUL, X), \ + INSN_3(ALU64, MOV, X), \ + INSN_3(ALU64, ARSH, X), \ + INSN_3(ALU64, DIV, X), \ + INSN_3(ALU64, MOD, X), \ + INSN_2(ALU64, NEG), \ + /* Immediate based. */ \ + INSN_3(ALU64, ADD, K), \ + INSN_3(ALU64, SUB, K), \ + INSN_3(ALU64, AND, K), \ + INSN_3(ALU64, OR, K), \ + INSN_3(ALU64, LSH, K), \ + INSN_3(ALU64, RSH, K), \ + INSN_3(ALU64, XOR, K), \ + INSN_3(ALU64, MUL, K), \ + INSN_3(ALU64, MOV, K), \ + INSN_3(ALU64, ARSH, K), \ + INSN_3(ALU64, DIV, K), \ + INSN_3(ALU64, MOD, K), \ + /* Call instruction. */ \ + INSN_2(JMP, CALL), \ + /* Exit instruction. */ \ + INSN_2(JMP, EXIT), \ + /* Jump instructions. */ \ + /* Register based. */ \ + INSN_3(JMP, JEQ, X), \ + INSN_3(JMP, JNE, X), \ + INSN_3(JMP, JGT, X), \ + INSN_3(JMP, JLT, X), \ + INSN_3(JMP, JGE, X), \ + INSN_3(JMP, JLE, X), \ + INSN_3(JMP, JSGT, X), \ + INSN_3(JMP, JSLT, X), \ + INSN_3(JMP, JSGE, X), \ + INSN_3(JMP, JSLE, X), \ + INSN_3(JMP, JSET, X), \ + /* Immediate based. */ \ + INSN_3(JMP, JEQ, K), \ + INSN_3(JMP, JNE, K), \ + INSN_3(JMP, JGT, K), \ + INSN_3(JMP, JLT, K), \ + INSN_3(JMP, JGE, K), \ + INSN_3(JMP, JLE, K), \ + INSN_3(JMP, JSGT, K), \ + INSN_3(JMP, JSLT, K), \ + INSN_3(JMP, JSGE, K), \ + INSN_3(JMP, JSLE, K), \ + INSN_3(JMP, JSET, K), \ + INSN_2(JMP, JA), \ + /* Store instructions. */ \ + /* Register based. */ \ + INSN_3(STX, MEM, B), \ + INSN_3(STX, MEM, H), \ + INSN_3(STX, MEM, W), \ + INSN_3(STX, MEM, DW), \ + INSN_3(STX, XADD, W), \ + INSN_3(STX, XADD, DW), \ + /* Immediate based. */ \ + INSN_3(ST, MEM, B), \ + INSN_3(ST, MEM, H), \ + INSN_3(ST, MEM, W), \ + INSN_3(ST, MEM, DW), \ + /* Load instructions. */ \ + /* Register based. */ \ + INSN_3(LDX, MEM, B), \ + INSN_3(LDX, MEM, H), \ + INSN_3(LDX, MEM, W), \ + INSN_3(LDX, MEM, DW), \ + /* Immediate based. */ \ + INSN_3(LD, IMM, DW), \ + /* Misc (old cBPF carry-over). */ \ + INSN_3(LD, ABS, B), \ + INSN_3(LD, ABS, H), \ + INSN_3(LD, ABS, W), \ + INSN_3(LD, IND, B), \ + INSN_3(LD, IND, H), \ + INSN_3(LD, IND, W) + +bool bpf_opcode_in_insntable(u8 code) +{ +#define BPF_INSN_2_TBL(x, y) [BPF_##x | BPF_##y] = true +#define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true + static const bool public_insntable[256] = { + [0 ... 255] = false, + /* Now overwrite non-defaults ... */ + BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL), + }; +#undef BPF_INSN_3_TBL +#undef BPF_INSN_2_TBL + return public_insntable[code]; +} + #ifndef CONFIG_BPF_JIT_ALWAYS_ON /** * __bpf_prog_run - run eBPF program on a given context @@ -775,118 +921,21 @@ EXPORT_SYMBOL_GPL(__bpf_call_base); * * Decode and execute eBPF instructions. */ -static unsigned int ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, - u64 *stack) +static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack) { u64 tmp; +#define BPF_INSN_2_LBL(x, y) [BPF_##x | BPF_##y] = &&x##_##y +#define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z static const void *jumptable[256] = { [0 ... 255] = &&default_label, /* Now overwrite non-defaults ... */ - /* 32 bit ALU operations */ - [BPF_ALU | BPF_ADD | BPF_X] = &&ALU_ADD_X, - [BPF_ALU | BPF_ADD | BPF_K] = &&ALU_ADD_K, - [BPF_ALU | BPF_SUB | BPF_X] = &&ALU_SUB_X, - [BPF_ALU | BPF_SUB | BPF_K] = &&ALU_SUB_K, - [BPF_ALU | BPF_AND | BPF_X] = &&ALU_AND_X, - [BPF_ALU | BPF_AND | BPF_K] = &&ALU_AND_K, - [BPF_ALU | BPF_OR | BPF_X] = &&ALU_OR_X, - [BPF_ALU | BPF_OR | BPF_K] = &&ALU_OR_K, - [BPF_ALU | BPF_LSH | BPF_X] = &&ALU_LSH_X, - [BPF_ALU | BPF_LSH | BPF_K] = &&ALU_LSH_K, - [BPF_ALU | BPF_RSH | BPF_X] = &&ALU_RSH_X, - [BPF_ALU | BPF_RSH | BPF_K] = &&ALU_RSH_K, - [BPF_ALU | BPF_XOR | BPF_X] = &&ALU_XOR_X, - [BPF_ALU | BPF_XOR | BPF_K] = &&ALU_XOR_K, - [BPF_ALU | BPF_MUL | BPF_X] = &&ALU_MUL_X, - [BPF_ALU | BPF_MUL | BPF_K] = &&ALU_MUL_K, - [BPF_ALU | BPF_MOV | BPF_X] = &&ALU_MOV_X, - [BPF_ALU | BPF_MOV | BPF_K] = &&ALU_MOV_K, - [BPF_ALU | BPF_DIV | BPF_X] = &&ALU_DIV_X, - [BPF_ALU | BPF_DIV | BPF_K] = &&ALU_DIV_K, - [BPF_ALU | BPF_MOD | BPF_X] = &&ALU_MOD_X, - [BPF_ALU | BPF_MOD | BPF_K] = &&ALU_MOD_K, - [BPF_ALU | BPF_NEG] = &&ALU_NEG, - [BPF_ALU | BPF_END | BPF_TO_BE] = &&ALU_END_TO_BE, - [BPF_ALU | BPF_END | BPF_TO_LE] = &&ALU_END_TO_LE, - /* 64 bit ALU operations */ - [BPF_ALU64 | BPF_ADD | BPF_X] = &&ALU64_ADD_X, - [BPF_ALU64 | BPF_ADD | BPF_K] = &&ALU64_ADD_K, - [BPF_ALU64 | BPF_SUB | BPF_X] = &&ALU64_SUB_X, - [BPF_ALU64 | BPF_SUB | BPF_K] = &&ALU64_SUB_K, - [BPF_ALU64 | BPF_AND | BPF_X] = &&ALU64_AND_X, - [BPF_ALU64 | BPF_AND | BPF_K] = &&ALU64_AND_K, - [BPF_ALU64 | BPF_OR | BPF_X] = &&ALU64_OR_X, - [BPF_ALU64 | BPF_OR | BPF_K] = &&ALU64_OR_K, - [BPF_ALU64 | BPF_LSH | BPF_X] = &&ALU64_LSH_X, - [BPF_ALU64 | BPF_LSH | BPF_K] = &&ALU64_LSH_K, - [BPF_ALU64 | BPF_RSH | BPF_X] = &&ALU64_RSH_X, - [BPF_ALU64 | BPF_RSH | BPF_K] = &&ALU64_RSH_K, - [BPF_ALU64 | BPF_XOR | BPF_X] = &&ALU64_XOR_X, - [BPF_ALU64 | BPF_XOR | BPF_K] = &&ALU64_XOR_K, - [BPF_ALU64 | BPF_MUL | BPF_X] = &&ALU64_MUL_X, - [BPF_ALU64 | BPF_MUL | BPF_K] = &&ALU64_MUL_K, - [BPF_ALU64 | BPF_MOV | BPF_X] = &&ALU64_MOV_X, - [BPF_ALU64 | BPF_MOV | BPF_K] = &&ALU64_MOV_K, - [BPF_ALU64 | BPF_ARSH | BPF_X] = &&ALU64_ARSH_X, - [BPF_ALU64 | BPF_ARSH | BPF_K] = &&ALU64_ARSH_K, - [BPF_ALU64 | BPF_DIV | BPF_X] = &&ALU64_DIV_X, - [BPF_ALU64 | BPF_DIV | BPF_K] = &&ALU64_DIV_K, - [BPF_ALU64 | BPF_MOD | BPF_X] = &&ALU64_MOD_X, - [BPF_ALU64 | BPF_MOD | BPF_K] = &&ALU64_MOD_K, - [BPF_ALU64 | BPF_NEG] = &&ALU64_NEG, - /* Call instruction */ - [BPF_JMP | BPF_CALL] = &&JMP_CALL, + BPF_INSN_MAP(BPF_INSN_2_LBL, BPF_INSN_3_LBL), + /* Non-UAPI available opcodes. */ + [BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS, [BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL, - /* Jumps */ - [BPF_JMP | BPF_JA] = &&JMP_JA, - [BPF_JMP | BPF_JEQ | BPF_X] = &&JMP_JEQ_X, - [BPF_JMP | BPF_JEQ | BPF_K] = &&JMP_JEQ_K, - [BPF_JMP | BPF_JNE | BPF_X] = &&JMP_JNE_X, - [BPF_JMP | BPF_JNE | BPF_K] = &&JMP_JNE_K, - [BPF_JMP | BPF_JGT | BPF_X] = &&JMP_JGT_X, - [BPF_JMP | BPF_JGT | BPF_K] = &&JMP_JGT_K, - [BPF_JMP | BPF_JLT | BPF_X] = &&JMP_JLT_X, - [BPF_JMP | BPF_JLT | BPF_K] = &&JMP_JLT_K, - [BPF_JMP | BPF_JGE | BPF_X] = &&JMP_JGE_X, - [BPF_JMP | BPF_JGE | BPF_K] = &&JMP_JGE_K, - [BPF_JMP | BPF_JLE | BPF_X] = &&JMP_JLE_X, - [BPF_JMP | BPF_JLE | BPF_K] = &&JMP_JLE_K, - [BPF_JMP | BPF_JSGT | BPF_X] = &&JMP_JSGT_X, - [BPF_JMP | BPF_JSGT | BPF_K] = &&JMP_JSGT_K, - [BPF_JMP | BPF_JSLT | BPF_X] = &&JMP_JSLT_X, - [BPF_JMP | BPF_JSLT | BPF_K] = &&JMP_JSLT_K, - [BPF_JMP | BPF_JSGE | BPF_X] = &&JMP_JSGE_X, - [BPF_JMP | BPF_JSGE | BPF_K] = &&JMP_JSGE_K, - [BPF_JMP | BPF_JSLE | BPF_X] = &&JMP_JSLE_X, - [BPF_JMP | BPF_JSLE | BPF_K] = &&JMP_JSLE_K, - [BPF_JMP | BPF_JSET | BPF_X] = &&JMP_JSET_X, - [BPF_JMP | BPF_JSET | BPF_K] = &&JMP_JSET_K, - /* Program return */ - [BPF_JMP | BPF_EXIT] = &&JMP_EXIT, - /* Store instructions */ - [BPF_STX | BPF_MEM | BPF_B] = &&STX_MEM_B, - [BPF_STX | BPF_MEM | BPF_H] = &&STX_MEM_H, - [BPF_STX | BPF_MEM | BPF_W] = &&STX_MEM_W, - [BPF_STX | BPF_MEM | BPF_DW] = &&STX_MEM_DW, - [BPF_STX | BPF_XADD | BPF_W] = &&STX_XADD_W, - [BPF_STX | BPF_XADD | BPF_DW] = &&STX_XADD_DW, - [BPF_ST | BPF_MEM | BPF_B] = &&ST_MEM_B, - [BPF_ST | BPF_MEM | BPF_H] = &&ST_MEM_H, - [BPF_ST | BPF_MEM | BPF_W] = &&ST_MEM_W, - [BPF_ST | BPF_MEM | BPF_DW] = &&ST_MEM_DW, - /* Load instructions */ - [BPF_LDX | BPF_MEM | BPF_B] = &&LDX_MEM_B, - [BPF_LDX | BPF_MEM | BPF_H] = &&LDX_MEM_H, - [BPF_LDX | BPF_MEM | BPF_W] = &&LDX_MEM_W, - [BPF_LDX | BPF_MEM | BPF_DW] = &&LDX_MEM_DW, - [BPF_LD | BPF_ABS | BPF_W] = &&LD_ABS_W, - [BPF_LD | BPF_ABS | BPF_H] = &&LD_ABS_H, - [BPF_LD | BPF_ABS | BPF_B] = &&LD_ABS_B, - [BPF_LD | BPF_IND | BPF_W] = &&LD_IND_W, - [BPF_LD | BPF_IND | BPF_H] = &&LD_IND_H, - [BPF_LD | BPF_IND | BPF_B] = &&LD_IND_B, - [BPF_LD | BPF_IMM | BPF_DW] = &&LD_IMM_DW, }; +#undef BPF_INSN_3_LBL +#undef BPF_INSN_2_LBL u32 tail_call_cnt = 0; void *ptr; int off; @@ -950,14 +999,10 @@ select_insn: (*(s64 *) &DST) >>= IMM; CONT; ALU64_MOD_X: - if (unlikely(SRC == 0)) - return 0; div64_u64_rem(DST, SRC, &tmp); DST = tmp; CONT; ALU_MOD_X: - if (unlikely((u32)SRC == 0)) - return 0; tmp = (u32) DST; DST = do_div(tmp, (u32) SRC); CONT; @@ -970,13 +1015,9 @@ select_insn: DST = do_div(tmp, (u32) IMM); CONT; ALU64_DIV_X: - if (unlikely(SRC == 0)) - return 0; DST = div64_u64(DST, SRC); CONT; ALU_DIV_X: - if (unlikely((u32)SRC == 0)) - return 0; tmp = (u32) DST; do_div(tmp, (u32) SRC); DST = (u32) tmp; @@ -1026,6 +1067,13 @@ select_insn: BPF_R4, BPF_R5); CONT; + JMP_CALL_ARGS: + BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2, + BPF_R3, BPF_R4, + BPF_R5, + insn + insn->off + 1); + CONT; + JMP_TAIL_CALL: { struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2; struct bpf_array *array = container_of(map, struct bpf_array, map); @@ -1280,8 +1328,14 @@ load_byte: goto load_byte; default_label: - /* If we ever reach this, we have a bug somewhere. */ - WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code); + /* If we ever reach this, we have a bug somewhere. Die hard here + * instead of just returning 0; we could be somewhere in a subprog, + * so execution could continue otherwise which we do /not/ want. + * + * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable(). + */ + pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code); + BUG_ON(1); return 0; } STACK_FRAME_NON_STANDARD(___bpf_prog_run); /* jump table */ @@ -1298,6 +1352,23 @@ static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn return ___bpf_prog_run(regs, insn, stack); \ } +#define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size +#define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \ +static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \ + const struct bpf_insn *insn) \ +{ \ + u64 stack[stack_size / sizeof(u64)]; \ + u64 regs[MAX_BPF_REG]; \ +\ + FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \ + BPF_R1 = r1; \ + BPF_R2 = r2; \ + BPF_R3 = r3; \ + BPF_R4 = r4; \ + BPF_R5 = r5; \ + return ___bpf_prog_run(regs, insn, stack); \ +} + #define EVAL1(FN, X) FN(X) #define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y) #define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y) @@ -1309,6 +1380,10 @@ EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192); EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384); EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512); +EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192); +EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384); +EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512); + #define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size), static unsigned int (*interpreters[])(const void *ctx, @@ -1317,11 +1392,33 @@ EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192) EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384) EVAL4(PROG_NAME_LIST, 416, 448, 480, 512) }; +#undef PROG_NAME_LIST +#define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size), +static u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, + const struct bpf_insn *insn) = { +EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192) +EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384) +EVAL4(PROG_NAME_LIST, 416, 448, 480, 512) +}; +#undef PROG_NAME_LIST + +void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth) +{ + stack_depth = max_t(u32, stack_depth, 1); + insn->off = (s16) insn->imm; + insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] - + __bpf_call_base_args; + insn->code = BPF_JMP | BPF_CALL_ARGS; +} #else -static unsigned int __bpf_prog_ret0(const void *ctx, - const struct bpf_insn *insn) +static unsigned int __bpf_prog_ret0_warn(const void *ctx, + const struct bpf_insn *insn) { + /* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON + * is not working properly, so warn about it! + */ + WARN_ON_ONCE(1); return 0; } #endif @@ -1329,6 +1426,9 @@ static unsigned int __bpf_prog_ret0(const void *ctx, bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp) { + if (fp->kprobe_override) + return false; + if (!array->owner_prog_type) { /* There's no owner yet where we could check for * compatibility. @@ -1378,7 +1478,7 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err) fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1]; #else - fp->bpf_func = __bpf_prog_ret0; + fp->bpf_func = __bpf_prog_ret0_warn; #endif /* eBPF JITs can rewrite the program in case constant @@ -1481,6 +1581,8 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs, rcu_read_lock(); prog = rcu_dereference(progs)->progs; for (; *prog; prog++) { + if (*prog == &dummy_bpf_prog.prog) + continue; id = (*prog)->aux->id; if (copy_to_user(prog_ids + i, &id, sizeof(id))) { rcu_read_unlock(); @@ -1564,14 +1666,41 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array, return 0; } +int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array, + __u32 __user *prog_ids, u32 request_cnt, + __u32 __user *prog_cnt) +{ + u32 cnt = 0; + + if (array) + cnt = bpf_prog_array_length(array); + + if (copy_to_user(prog_cnt, &cnt, sizeof(cnt))) + return -EFAULT; + + /* return early if user requested only program count or nothing to copy */ + if (!request_cnt || !cnt) + return 0; + + return bpf_prog_array_copy_to_user(array, prog_ids, request_cnt); +} + static void bpf_prog_free_deferred(struct work_struct *work) { struct bpf_prog_aux *aux; + int i; aux = container_of(work, struct bpf_prog_aux, work); if (bpf_prog_is_dev_bound(aux)) bpf_prog_offload_destroy(aux->prog); - bpf_jit_free(aux->prog); + for (i = 0; i < aux->func_cnt; i++) + bpf_jit_free(aux->func[i]); + if (aux->func_cnt) { + kfree(aux->func); + bpf_prog_unlock_free(aux->prog); + } else { + bpf_jit_free(aux->prog); + } } /* Free internal BPF program */ diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index ce5b669..fbfdada6 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -94,13 +94,7 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) if (!cmap) return ERR_PTR(-ENOMEM); - /* mandatory map attributes */ - cmap->map.map_type = attr->map_type; - cmap->map.key_size = attr->key_size; - cmap->map.value_size = attr->value_size; - cmap->map.max_entries = attr->max_entries; - cmap->map.map_flags = attr->map_flags; - cmap->map.numa_node = bpf_map_attr_numa_node(attr); + bpf_map_init_from_attr(&cmap->map, attr); /* Pre-limit array size based on NR_CPUS, not final CPU check */ if (cmap->map.max_entries > NR_CPUS) { @@ -143,7 +137,7 @@ free_cmap: return ERR_PTR(err); } -void __cpu_map_queue_destructor(void *ptr) +static void __cpu_map_queue_destructor(void *ptr) { /* The tear-down procedure should have made sure that queue is * empty. See __cpu_map_entry_replace() and work-queue @@ -222,8 +216,8 @@ static struct xdp_pkt *convert_to_xdp_pkt(struct xdp_buff *xdp) return xdp_pkt; } -struct sk_buff *cpu_map_build_skb(struct bpf_cpu_map_entry *rcpu, - struct xdp_pkt *xdp_pkt) +static struct sk_buff *cpu_map_build_skb(struct bpf_cpu_map_entry *rcpu, + struct xdp_pkt *xdp_pkt) { unsigned int frame_size; void *pkt_data_start; @@ -337,7 +331,8 @@ static int cpu_map_kthread_run(void *data) return 0; } -struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu, int map_id) +static struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu, + int map_id) { gfp_t gfp = GFP_ATOMIC|__GFP_NOWARN; struct bpf_cpu_map_entry *rcpu; @@ -395,7 +390,7 @@ free_rcu: return NULL; } -void __cpu_map_entry_free(struct rcu_head *rcu) +static void __cpu_map_entry_free(struct rcu_head *rcu) { struct bpf_cpu_map_entry *rcpu; int cpu; @@ -438,8 +433,8 @@ void __cpu_map_entry_free(struct rcu_head *rcu) * cpu_map_kthread_stop, which waits for an RCU graze period before * stopping kthread, emptying the queue. */ -void __cpu_map_entry_replace(struct bpf_cpu_map *cmap, - u32 key_cpu, struct bpf_cpu_map_entry *rcpu) +static void __cpu_map_entry_replace(struct bpf_cpu_map *cmap, + u32 key_cpu, struct bpf_cpu_map_entry *rcpu) { struct bpf_cpu_map_entry *old_rcpu; @@ -451,7 +446,7 @@ void __cpu_map_entry_replace(struct bpf_cpu_map *cmap, } } -int cpu_map_delete_elem(struct bpf_map *map, void *key) +static int cpu_map_delete_elem(struct bpf_map *map, void *key) { struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); u32 key_cpu = *(u32 *)key; @@ -464,8 +459,8 @@ int cpu_map_delete_elem(struct bpf_map *map, void *key) return 0; } -int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, - u64 map_flags) +static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, + u64 map_flags) { struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); struct bpf_cpu_map_entry *rcpu; @@ -502,7 +497,7 @@ int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, return 0; } -void cpu_map_free(struct bpf_map *map) +static void cpu_map_free(struct bpf_map *map) { struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); int cpu; diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index ebdef54..565f9ec 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -93,13 +93,7 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr) if (!dtab) return ERR_PTR(-ENOMEM); - /* mandatory map attributes */ - dtab->map.map_type = attr->map_type; - dtab->map.key_size = attr->key_size; - dtab->map.value_size = attr->value_size; - dtab->map.max_entries = attr->max_entries; - dtab->map.map_flags = attr->map_flags; - dtab->map.numa_node = bpf_map_attr_numa_node(attr); + bpf_map_init_from_attr(&dtab->map, attr); /* make sure page count doesn't overflow */ cost = (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *); diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c index e682850..8740406 100644 --- a/kernel/bpf/disasm.c +++ b/kernel/bpf/disasm.c @@ -21,10 +21,39 @@ static const char * const func_id_str[] = { }; #undef __BPF_FUNC_STR_FN -const char *func_id_name(int id) +static const char *__func_get_name(const struct bpf_insn_cbs *cbs, + const struct bpf_insn *insn, + char *buff, size_t len) { BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID); + if (insn->src_reg != BPF_PSEUDO_CALL && + insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID && + func_id_str[insn->imm]) + return func_id_str[insn->imm]; + + if (cbs && cbs->cb_call) + return cbs->cb_call(cbs->private_data, insn); + + if (insn->src_reg == BPF_PSEUDO_CALL) + snprintf(buff, len, "%+d", insn->imm); + + return buff; +} + +static const char *__func_imm_name(const struct bpf_insn_cbs *cbs, + const struct bpf_insn *insn, + u64 full_imm, char *buff, size_t len) +{ + if (cbs && cbs->cb_imm) + return cbs->cb_imm(cbs->private_data, insn, full_imm); + + snprintf(buff, len, "0x%llx", (unsigned long long)full_imm); + return buff; +} + +const char *func_id_name(int id) +{ if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id]) return func_id_str[id]; else @@ -83,7 +112,7 @@ static const char *const bpf_jmp_string[16] = { [BPF_EXIT >> 4] = "exit", }; -static void print_bpf_end_insn(bpf_insn_print_cb verbose, +static void print_bpf_end_insn(bpf_insn_print_t verbose, struct bpf_verifier_env *env, const struct bpf_insn *insn) { @@ -92,9 +121,12 @@ static void print_bpf_end_insn(bpf_insn_print_cb verbose, insn->imm, insn->dst_reg); } -void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, - const struct bpf_insn *insn, bool allow_ptr_leaks) +void print_bpf_insn(const struct bpf_insn_cbs *cbs, + struct bpf_verifier_env *env, + const struct bpf_insn *insn, + bool allow_ptr_leaks) { + const bpf_insn_print_t verbose = cbs->cb_print; u8 class = BPF_CLASS(insn->code); if (class == BPF_ALU || class == BPF_ALU64) { @@ -175,12 +207,15 @@ void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, */ u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm; bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD; + char tmp[64]; if (map_ptr && !allow_ptr_leaks) imm = 0; - verbose(env, "(%02x) r%d = 0x%llx\n", insn->code, - insn->dst_reg, (unsigned long long)imm); + verbose(env, "(%02x) r%d = %s\n", + insn->code, insn->dst_reg, + __func_imm_name(cbs, insn, imm, + tmp, sizeof(tmp))); } else { verbose(env, "BUG_ld_%02x\n", insn->code); return; @@ -189,8 +224,20 @@ void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, u8 opcode = BPF_OP(insn->code); if (opcode == BPF_CALL) { - verbose(env, "(%02x) call %s#%d\n", insn->code, - func_id_name(insn->imm), insn->imm); + char tmp[64]; + + if (insn->src_reg == BPF_PSEUDO_CALL) { + verbose(env, "(%02x) call pc%s\n", + insn->code, + __func_get_name(cbs, insn, + tmp, sizeof(tmp))); + } else { + strcpy(tmp, "unknown"); + verbose(env, "(%02x) call %s#%d\n", insn->code, + __func_get_name(cbs, insn, + tmp, sizeof(tmp)), + insn->imm); + } } else if (insn->code == (BPF_JMP | BPF_JA)) { verbose(env, "(%02x) goto pc%+d\n", insn->code, insn->off); diff --git a/kernel/bpf/disasm.h b/kernel/bpf/disasm.h index 8de977e..266fe8e 100644 --- a/kernel/bpf/disasm.h +++ b/kernel/bpf/disasm.h @@ -17,16 +17,35 @@ #include <linux/bpf.h> #include <linux/kernel.h> #include <linux/stringify.h> +#ifndef __KERNEL__ +#include <stdio.h> +#include <string.h> +#endif + +struct bpf_verifier_env; extern const char *const bpf_alu_string[16]; extern const char *const bpf_class_string[8]; const char *func_id_name(int id); -struct bpf_verifier_env; -typedef void (*bpf_insn_print_cb)(struct bpf_verifier_env *env, - const char *, ...); -void print_bpf_insn(bpf_insn_print_cb verbose, struct bpf_verifier_env *env, - const struct bpf_insn *insn, bool allow_ptr_leaks); +typedef __printf(2, 3) void (*bpf_insn_print_t)(struct bpf_verifier_env *env, + const char *, ...); +typedef const char *(*bpf_insn_revmap_call_t)(void *private_data, + const struct bpf_insn *insn); +typedef const char *(*bpf_insn_print_imm_t)(void *private_data, + const struct bpf_insn *insn, + __u64 full_imm); + +struct bpf_insn_cbs { + bpf_insn_print_t cb_print; + bpf_insn_revmap_call_t cb_call; + bpf_insn_print_imm_t cb_imm; + void *private_data; +}; +void print_bpf_insn(const struct bpf_insn_cbs *cbs, + struct bpf_verifier_env *env, + const struct bpf_insn *insn, + bool allow_ptr_leaks); #endif diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 3905d4b..b76828f 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -227,7 +227,7 @@ static int alloc_extra_elems(struct bpf_htab *htab) } /* Called from syscall */ -static struct bpf_map *htab_map_alloc(union bpf_attr *attr) +static int htab_map_alloc_check(union bpf_attr *attr) { bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH || attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH); @@ -241,9 +241,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU); bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC); int numa_node = bpf_map_attr_numa_node(attr); - struct bpf_htab *htab; - int err, i; - u64 cost; BUILD_BUG_ON(offsetof(struct htab_elem, htab) != offsetof(struct htab_elem, hash_node.pprev)); @@ -254,40 +251,68 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) /* LRU implementation is much complicated than other * maps. Hence, limit to CAP_SYS_ADMIN for now. */ - return ERR_PTR(-EPERM); + return -EPERM; if (attr->map_flags & ~HTAB_CREATE_FLAG_MASK) /* reserved bits should not be used */ - return ERR_PTR(-EINVAL); + return -EINVAL; if (!lru && percpu_lru) - return ERR_PTR(-EINVAL); + return -EINVAL; if (lru && !prealloc) - return ERR_PTR(-ENOTSUPP); + return -ENOTSUPP; if (numa_node != NUMA_NO_NODE && (percpu || percpu_lru)) - return ERR_PTR(-EINVAL); + return -EINVAL; + + /* check sanity of attributes. + * value_size == 0 may be allowed in the future to use map as a set + */ + if (attr->max_entries == 0 || attr->key_size == 0 || + attr->value_size == 0) + return -EINVAL; + + if (attr->key_size > MAX_BPF_STACK) + /* eBPF programs initialize keys on stack, so they cannot be + * larger than max stack size + */ + return -E2BIG; + + if (attr->value_size >= KMALLOC_MAX_SIZE - + MAX_BPF_STACK - sizeof(struct htab_elem)) + /* if value_size is bigger, the user space won't be able to + * access the elements via bpf syscall. This check also makes + * sure that the elem_size doesn't overflow and it's + * kmalloc-able later in htab_map_update_elem() + */ + return -E2BIG; + + return 0; +} + +static struct bpf_map *htab_map_alloc(union bpf_attr *attr) +{ + bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH || + attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH); + bool lru = (attr->map_type == BPF_MAP_TYPE_LRU_HASH || + attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH); + /* percpu_lru means each cpu has its own LRU list. + * it is different from BPF_MAP_TYPE_PERCPU_HASH where + * the map's value itself is percpu. percpu_lru has + * nothing to do with the map's value. + */ + bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU); + bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC); + struct bpf_htab *htab; + int err, i; + u64 cost; htab = kzalloc(sizeof(*htab), GFP_USER); if (!htab) return ERR_PTR(-ENOMEM); - /* mandatory map attributes */ - htab->map.map_type = attr->map_type; - htab->map.key_size = attr->key_size; - htab->map.value_size = attr->value_size; - htab->map.max_entries = attr->max_entries; - htab->map.map_flags = attr->map_flags; - htab->map.numa_node = numa_node; - - /* check sanity of attributes. - * value_size == 0 may be allowed in the future to use map as a set - */ - err = -EINVAL; - if (htab->map.max_entries == 0 || htab->map.key_size == 0 || - htab->map.value_size == 0) - goto free_htab; + bpf_map_init_from_attr(&htab->map, attr); if (percpu_lru) { /* ensure each CPU's lru list has >=1 elements. @@ -304,22 +329,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) /* hash table size must be power of 2 */ htab->n_buckets = roundup_pow_of_two(htab->map.max_entries); - err = -E2BIG; - if (htab->map.key_size > MAX_BPF_STACK) - /* eBPF programs initialize keys on stack, so they cannot be - * larger than max stack size - */ - goto free_htab; - - if (htab->map.value_size >= KMALLOC_MAX_SIZE - - MAX_BPF_STACK - sizeof(struct htab_elem)) - /* if value_size is bigger, the user space won't be able to - * access the elements via bpf syscall. This check also makes - * sure that the elem_size doesn't overflow and it's - * kmalloc-able later in htab_map_update_elem() - */ - goto free_htab; - htab->elem_size = sizeof(struct htab_elem) + round_up(htab->map.key_size, 8); if (percpu) @@ -327,6 +336,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) else htab->elem_size += round_up(htab->map.value_size, 8); + err = -E2BIG; /* prevent zero size kmalloc and check for u32 overflow */ if (htab->n_buckets == 0 || htab->n_buckets > U32_MAX / sizeof(struct bucket)) @@ -1143,6 +1153,7 @@ static void htab_map_free(struct bpf_map *map) } const struct bpf_map_ops htab_map_ops = { + .map_alloc_check = htab_map_alloc_check, .map_alloc = htab_map_alloc, .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, @@ -1153,6 +1164,7 @@ const struct bpf_map_ops htab_map_ops = { }; const struct bpf_map_ops htab_lru_map_ops = { + .map_alloc_check = htab_map_alloc_check, .map_alloc = htab_map_alloc, .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, @@ -1236,6 +1248,7 @@ int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value, } const struct bpf_map_ops htab_percpu_map_ops = { + .map_alloc_check = htab_map_alloc_check, .map_alloc = htab_map_alloc, .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, @@ -1245,6 +1258,7 @@ const struct bpf_map_ops htab_percpu_map_ops = { }; const struct bpf_map_ops htab_lru_percpu_map_ops = { + .map_alloc_check = htab_map_alloc_check, .map_alloc = htab_map_alloc, .map_free = htab_map_free, .map_get_next_key = htab_map_get_next_key, @@ -1253,11 +1267,11 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = { .map_delete_elem = htab_lru_map_delete_elem, }; -static struct bpf_map *fd_htab_map_alloc(union bpf_attr *attr) +static int fd_htab_map_alloc_check(union bpf_attr *attr) { if (attr->value_size != sizeof(u32)) - return ERR_PTR(-EINVAL); - return htab_map_alloc(attr); + return -EINVAL; + return htab_map_alloc_check(attr); } static void fd_htab_map_free(struct bpf_map *map) @@ -1328,7 +1342,7 @@ static struct bpf_map *htab_of_map_alloc(union bpf_attr *attr) if (IS_ERR(inner_map_meta)) return inner_map_meta; - map = fd_htab_map_alloc(attr); + map = htab_map_alloc(attr); if (IS_ERR(map)) { bpf_map_meta_free(inner_map_meta); return map; @@ -1372,6 +1386,7 @@ static void htab_of_map_free(struct bpf_map *map) } const struct bpf_map_ops htab_of_maps_map_ops = { + .map_alloc_check = fd_htab_map_alloc_check, .map_alloc = htab_of_map_alloc, .map_free = htab_of_map_free, .map_get_next_key = htab_map_get_next_key, diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index 5bb5e49..81e2f69 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -150,39 +150,29 @@ static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) return 0; } -static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry, - umode_t mode, const struct inode_operations *iops) +static int bpf_mkobj_ops(struct dentry *dentry, umode_t mode, void *raw, + const struct inode_operations *iops) { - struct inode *inode; - - inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG); + struct inode *dir = dentry->d_parent->d_inode; + struct inode *inode = bpf_get_inode(dir->i_sb, dir, mode); if (IS_ERR(inode)) return PTR_ERR(inode); inode->i_op = iops; - inode->i_private = dentry->d_fsdata; + inode->i_private = raw; bpf_dentry_finalize(dentry, inode, dir); return 0; } -static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode, - dev_t devt) +static int bpf_mkprog(struct dentry *dentry, umode_t mode, void *arg) { - enum bpf_type type = MINOR(devt); - - if (MAJOR(devt) != UNNAMED_MAJOR || !S_ISREG(mode) || - dentry->d_fsdata == NULL) - return -EPERM; + return bpf_mkobj_ops(dentry, mode, arg, &bpf_prog_iops); +} - switch (type) { - case BPF_TYPE_PROG: - return bpf_mkobj_ops(dir, dentry, mode, &bpf_prog_iops); - case BPF_TYPE_MAP: - return bpf_mkobj_ops(dir, dentry, mode, &bpf_map_iops); - default: - return -EPERM; - } +static int bpf_mkmap(struct dentry *dentry, umode_t mode, void *arg) +{ + return bpf_mkobj_ops(dentry, mode, arg, &bpf_map_iops); } static struct dentry * @@ -218,7 +208,6 @@ static int bpf_symlink(struct inode *dir, struct dentry *dentry, static const struct inode_operations bpf_dir_iops = { .lookup = bpf_lookup, - .mknod = bpf_mkobj, .mkdir = bpf_mkdir, .symlink = bpf_symlink, .rmdir = simple_rmdir, @@ -234,7 +223,6 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, struct inode *dir; struct path path; umode_t mode; - dev_t devt; int ret; dentry = kern_path_create(AT_FDCWD, pathname->name, &path, 0); @@ -242,9 +230,8 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, return PTR_ERR(dentry); mode = S_IFREG | ((S_IRUSR | S_IWUSR) & ~current_umask()); - devt = MKDEV(UNNAMED_MAJOR, type); - ret = security_path_mknod(&path, dentry, mode, devt); + ret = security_path_mknod(&path, dentry, mode, 0); if (ret) goto out; @@ -254,9 +241,16 @@ static int bpf_obj_do_pin(const struct filename *pathname, void *raw, goto out; } - dentry->d_fsdata = raw; - ret = vfs_mknod(dir, dentry, mode, devt); - dentry->d_fsdata = NULL; + switch (type) { + case BPF_TYPE_PROG: + ret = vfs_mkobj(dentry, mode, bpf_mkprog, raw); + break; + case BPF_TYPE_MAP: + ret = vfs_mkobj(dentry, mode, bpf_mkmap, raw); + break; + default: + ret = -EPERM; + } out: done_path_create(&path, dentry); return ret; diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c index 885e4547..7b469d1 100644 --- a/kernel/bpf/lpm_trie.c +++ b/kernel/bpf/lpm_trie.c @@ -522,12 +522,7 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr) return ERR_PTR(-ENOMEM); /* copy mandatory map attributes */ - trie->map.map_type = attr->map_type; - trie->map.key_size = attr->key_size; - trie->map.value_size = attr->value_size; - trie->map.max_entries = attr->max_entries; - trie->map.map_flags = attr->map_flags; - trie->map.numa_node = bpf_map_attr_numa_node(attr); + bpf_map_init_from_attr(&trie->map, attr); trie->data_size = attr->key_size - offsetof(struct bpf_lpm_trie_key, data); trie->max_prefixlen = trie->data_size * 8; @@ -596,9 +591,96 @@ unlock: raw_spin_unlock(&trie->lock); } -static int trie_get_next_key(struct bpf_map *map, void *key, void *next_key) +static int trie_get_next_key(struct bpf_map *map, void *_key, void *_next_key) { - return -ENOTSUPP; + struct lpm_trie_node *node, *next_node = NULL, *parent, *search_root; + struct lpm_trie *trie = container_of(map, struct lpm_trie, map); + struct bpf_lpm_trie_key *key = _key, *next_key = _next_key; + struct lpm_trie_node **node_stack = NULL; + int err = 0, stack_ptr = -1; + unsigned int next_bit; + size_t matchlen; + + /* The get_next_key follows postorder. For the 4 node example in + * the top of this file, the trie_get_next_key() returns the following + * one after another: + * 192.168.0.0/24 + * 192.168.1.0/24 + * 192.168.128.0/24 + * 192.168.0.0/16 + * + * The idea is to return more specific keys before less specific ones. + */ + + /* Empty trie */ + search_root = rcu_dereference(trie->root); + if (!search_root) + return -ENOENT; + + /* For invalid key, find the leftmost node in the trie */ + if (!key || key->prefixlen > trie->max_prefixlen) + goto find_leftmost; + + node_stack = kmalloc(trie->max_prefixlen * sizeof(struct lpm_trie_node *), + GFP_ATOMIC | __GFP_NOWARN); + if (!node_stack) + return -ENOMEM; + + /* Try to find the exact node for the given key */ + for (node = search_root; node;) { + node_stack[++stack_ptr] = node; + matchlen = longest_prefix_match(trie, node, key); + if (node->prefixlen != matchlen || + node->prefixlen == key->prefixlen) + break; + + next_bit = extract_bit(key->data, node->prefixlen); + node = rcu_dereference(node->child[next_bit]); + } + if (!node || node->prefixlen != key->prefixlen || + (node->flags & LPM_TREE_NODE_FLAG_IM)) + goto find_leftmost; + + /* The node with the exactly-matching key has been found, + * find the first node in postorder after the matched node. + */ + node = node_stack[stack_ptr]; + while (stack_ptr > 0) { + parent = node_stack[stack_ptr - 1]; + if (rcu_dereference(parent->child[0]) == node) { + search_root = rcu_dereference(parent->child[1]); + if (search_root) + goto find_leftmost; + } + if (!(parent->flags & LPM_TREE_NODE_FLAG_IM)) { + next_node = parent; + goto do_copy; + } + + node = parent; + stack_ptr--; + } + + /* did not find anything */ + err = -ENOENT; + goto free_stack; + +find_leftmost: + /* Find the leftmost non-intermediate node, all intermediate nodes + * have exact two children, so this function will never return NULL. + */ + for (node = search_root; node;) { + if (!(node->flags & LPM_TREE_NODE_FLAG_IM)) + next_node = node; + node = rcu_dereference(node->child[0]); + } +do_copy: + next_key->prefixlen = next_node->prefixlen; + memcpy((void *)next_key + offsetof(struct bpf_lpm_trie_key, data), + next_node->data, trie->data_size); +free_stack: + kfree(node_stack); + return err; } const struct bpf_map_ops trie_map_ops = { diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index 8455b89..c940107 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -16,18 +16,35 @@ #include <linux/bpf.h> #include <linux/bpf_verifier.h> #include <linux/bug.h> +#include <linux/kdev_t.h> #include <linux/list.h> #include <linux/netdevice.h> #include <linux/printk.h> +#include <linux/proc_ns.h> #include <linux/rtnetlink.h> +#include <linux/rwsem.h> -/* protected by RTNL */ +/* Protects bpf_prog_offload_devs, bpf_map_offload_devs and offload members + * of all progs. + * RTNL lock cannot be taken when holding this lock. + */ +static DECLARE_RWSEM(bpf_devs_lock); static LIST_HEAD(bpf_prog_offload_devs); +static LIST_HEAD(bpf_map_offload_devs); + +static int bpf_dev_offload_check(struct net_device *netdev) +{ + if (!netdev) + return -EINVAL; + if (!netdev->netdev_ops->ndo_bpf) + return -EOPNOTSUPP; + return 0; +} int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr) { - struct net *net = current->nsproxy->net_ns; - struct bpf_dev_offload *offload; + struct bpf_prog_offload *offload; + int err; if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS && attr->prog_type != BPF_PROG_TYPE_XDP) @@ -41,34 +58,44 @@ int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr) return -ENOMEM; offload->prog = prog; - init_waitqueue_head(&offload->verifier_done); - rtnl_lock(); - offload->netdev = __dev_get_by_index(net, attr->prog_ifindex); - if (!offload->netdev) { - rtnl_unlock(); - kfree(offload); - return -EINVAL; - } + offload->netdev = dev_get_by_index(current->nsproxy->net_ns, + attr->prog_ifindex); + err = bpf_dev_offload_check(offload->netdev); + if (err) + goto err_maybe_put; + down_write(&bpf_devs_lock); + if (offload->netdev->reg_state != NETREG_REGISTERED) { + err = -EINVAL; + goto err_unlock; + } prog->aux->offload = offload; list_add_tail(&offload->offloads, &bpf_prog_offload_devs); - rtnl_unlock(); + dev_put(offload->netdev); + up_write(&bpf_devs_lock); return 0; +err_unlock: + up_write(&bpf_devs_lock); +err_maybe_put: + if (offload->netdev) + dev_put(offload->netdev); + kfree(offload); + return err; } static int __bpf_offload_ndo(struct bpf_prog *prog, enum bpf_netdev_command cmd, struct netdev_bpf *data) { - struct net_device *netdev = prog->aux->offload->netdev; + struct bpf_prog_offload *offload = prog->aux->offload; + struct net_device *netdev; ASSERT_RTNL(); - if (!netdev) + if (!offload) return -ENODEV; - if (!netdev->netdev_ops->ndo_bpf) - return -EOPNOTSUPP; + netdev = offload->netdev; data->command = cmd; @@ -87,62 +114,63 @@ int bpf_prog_offload_verifier_prep(struct bpf_verifier_env *env) if (err) goto exit_unlock; - env->dev_ops = data.verifier.ops; - + env->prog->aux->offload->dev_ops = data.verifier.ops; env->prog->aux->offload->dev_state = true; - env->prog->aux->offload->verifier_running = true; exit_unlock: rtnl_unlock(); return err; } +int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, + int insn_idx, int prev_insn_idx) +{ + struct bpf_prog_offload *offload; + int ret = -ENODEV; + + down_read(&bpf_devs_lock); + offload = env->prog->aux->offload; + if (offload) + ret = offload->dev_ops->insn_hook(env, insn_idx, prev_insn_idx); + up_read(&bpf_devs_lock); + + return ret; +} + static void __bpf_prog_offload_destroy(struct bpf_prog *prog) { - struct bpf_dev_offload *offload = prog->aux->offload; + struct bpf_prog_offload *offload = prog->aux->offload; struct netdev_bpf data = {}; - /* Caution - if netdev is destroyed before the program, this function - * will be called twice. - */ - data.offload.prog = prog; - if (offload->verifier_running) - wait_event(offload->verifier_done, !offload->verifier_running); - if (offload->dev_state) WARN_ON(__bpf_offload_ndo(prog, BPF_OFFLOAD_DESTROY, &data)); - offload->dev_state = false; + /* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */ + bpf_prog_free_id(prog, true); + list_del_init(&offload->offloads); - offload->netdev = NULL; + kfree(offload); + prog->aux->offload = NULL; } void bpf_prog_offload_destroy(struct bpf_prog *prog) { - struct bpf_dev_offload *offload = prog->aux->offload; - - offload->verifier_running = false; - wake_up(&offload->verifier_done); - rtnl_lock(); - __bpf_prog_offload_destroy(prog); + down_write(&bpf_devs_lock); + if (prog->aux->offload) + __bpf_prog_offload_destroy(prog); + up_write(&bpf_devs_lock); rtnl_unlock(); - - kfree(offload); } static int bpf_prog_offload_translate(struct bpf_prog *prog) { - struct bpf_dev_offload *offload = prog->aux->offload; struct netdev_bpf data = {}; int ret; data.offload.prog = prog; - offload->verifier_running = false; - wake_up(&offload->verifier_done); - rtnl_lock(); ret = __bpf_offload_ndo(prog, BPF_OFFLOAD_TRANSLATE, &data); rtnl_unlock(); @@ -164,14 +192,323 @@ int bpf_prog_offload_compile(struct bpf_prog *prog) return bpf_prog_offload_translate(prog); } +struct ns_get_path_bpf_prog_args { + struct bpf_prog *prog; + struct bpf_prog_info *info; +}; + +static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) +{ + struct ns_get_path_bpf_prog_args *args = private_data; + struct bpf_prog_aux *aux = args->prog->aux; + struct ns_common *ns; + struct net *net; + + rtnl_lock(); + down_read(&bpf_devs_lock); + + if (aux->offload) { + args->info->ifindex = aux->offload->netdev->ifindex; + net = dev_net(aux->offload->netdev); + get_net(net); + ns = &net->ns; + } else { + args->info->ifindex = 0; + ns = NULL; + } + + up_read(&bpf_devs_lock); + rtnl_unlock(); + + return ns; +} + +int bpf_prog_offload_info_fill(struct bpf_prog_info *info, + struct bpf_prog *prog) +{ + struct ns_get_path_bpf_prog_args args = { + .prog = prog, + .info = info, + }; + struct bpf_prog_aux *aux = prog->aux; + struct inode *ns_inode; + struct path ns_path; + char __user *uinsns; + void *res; + u32 ulen; + + res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); + if (IS_ERR(res)) { + if (!info->ifindex) + return -ENODEV; + return PTR_ERR(res); + } + + down_read(&bpf_devs_lock); + + if (!aux->offload) { + up_read(&bpf_devs_lock); + return -ENODEV; + } + + ulen = info->jited_prog_len; + info->jited_prog_len = aux->offload->jited_len; + if (info->jited_prog_len & ulen) { + uinsns = u64_to_user_ptr(info->jited_prog_insns); + ulen = min_t(u32, info->jited_prog_len, ulen); + if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { + up_read(&bpf_devs_lock); + return -EFAULT; + } + } + + up_read(&bpf_devs_lock); + + ns_inode = ns_path.dentry->d_inode; + info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); + info->netns_ino = ns_inode->i_ino; + path_put(&ns_path); + + return 0; +} + const struct bpf_prog_ops bpf_offload_prog_ops = { }; +static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap, + enum bpf_netdev_command cmd) +{ + struct netdev_bpf data = {}; + struct net_device *netdev; + + ASSERT_RTNL(); + + data.command = cmd; + data.offmap = offmap; + /* Caller must make sure netdev is valid */ + netdev = offmap->netdev; + + return netdev->netdev_ops->ndo_bpf(netdev, &data); +} + +struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) +{ + struct net *net = current->nsproxy->net_ns; + struct bpf_offloaded_map *offmap; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return ERR_PTR(-EPERM); + if (attr->map_type != BPF_MAP_TYPE_ARRAY && + attr->map_type != BPF_MAP_TYPE_HASH) + return ERR_PTR(-EINVAL); + + offmap = kzalloc(sizeof(*offmap), GFP_USER); + if (!offmap) + return ERR_PTR(-ENOMEM); + + bpf_map_init_from_attr(&offmap->map, attr); + + rtnl_lock(); + down_write(&bpf_devs_lock); + offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); + err = bpf_dev_offload_check(offmap->netdev); + if (err) + goto err_unlock; + + err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); + if (err) + goto err_unlock; + + list_add_tail(&offmap->offloads, &bpf_map_offload_devs); + up_write(&bpf_devs_lock); + rtnl_unlock(); + + return &offmap->map; + +err_unlock: + up_write(&bpf_devs_lock); + rtnl_unlock(); + kfree(offmap); + return ERR_PTR(err); +} + +static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap) +{ + WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE)); + /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */ + bpf_map_free_id(&offmap->map, true); + list_del_init(&offmap->offloads); + offmap->netdev = NULL; +} + +void bpf_map_offload_map_free(struct bpf_map *map) +{ + struct bpf_offloaded_map *offmap = map_to_offmap(map); + + rtnl_lock(); + down_write(&bpf_devs_lock); + if (offmap->netdev) + __bpf_map_offload_destroy(offmap); + up_write(&bpf_devs_lock); + rtnl_unlock(); + + kfree(offmap); +} + +int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) +{ + struct bpf_offloaded_map *offmap = map_to_offmap(map); + int ret = -ENODEV; + + down_read(&bpf_devs_lock); + if (offmap->netdev) + ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); + up_read(&bpf_devs_lock); + + return ret; +} + +int bpf_map_offload_update_elem(struct bpf_map *map, + void *key, void *value, u64 flags) +{ + struct bpf_offloaded_map *offmap = map_to_offmap(map); + int ret = -ENODEV; + + if (unlikely(flags > BPF_EXIST)) + return -EINVAL; + + down_read(&bpf_devs_lock); + if (offmap->netdev) + ret = offmap->dev_ops->map_update_elem(offmap, key, value, + flags); + up_read(&bpf_devs_lock); + + return ret; +} + +int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) +{ + struct bpf_offloaded_map *offmap = map_to_offmap(map); + int ret = -ENODEV; + + down_read(&bpf_devs_lock); + if (offmap->netdev) + ret = offmap->dev_ops->map_delete_elem(offmap, key); + up_read(&bpf_devs_lock); + + return ret; +} + +int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) +{ + struct bpf_offloaded_map *offmap = map_to_offmap(map); + int ret = -ENODEV; + + down_read(&bpf_devs_lock); + if (offmap->netdev) + ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); + up_read(&bpf_devs_lock); + + return ret; +} + +struct ns_get_path_bpf_map_args { + struct bpf_offloaded_map *offmap; + struct bpf_map_info *info; +}; + +static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) +{ + struct ns_get_path_bpf_map_args *args = private_data; + struct ns_common *ns; + struct net *net; + + rtnl_lock(); + down_read(&bpf_devs_lock); + + if (args->offmap->netdev) { + args->info->ifindex = args->offmap->netdev->ifindex; + net = dev_net(args->offmap->netdev); + get_net(net); + ns = &net->ns; + } else { + args->info->ifindex = 0; + ns = NULL; + } + + up_read(&bpf_devs_lock); + rtnl_unlock(); + + return ns; +} + +int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) +{ + struct ns_get_path_bpf_map_args args = { + .offmap = map_to_offmap(map), + .info = info, + }; + struct inode *ns_inode; + struct path ns_path; + void *res; + + res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); + if (IS_ERR(res)) { + if (!info->ifindex) + return -ENODEV; + return PTR_ERR(res); + } + + ns_inode = ns_path.dentry->d_inode; + info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); + info->netns_ino = ns_inode->i_ino; + path_put(&ns_path); + + return 0; +} + +bool bpf_offload_dev_match(struct bpf_prog *prog, struct bpf_map *map) +{ + struct bpf_offloaded_map *offmap; + struct bpf_prog_offload *offload; + bool ret; + + if (!bpf_prog_is_dev_bound(prog->aux) || !bpf_map_is_dev_bound(map)) + return false; + + down_read(&bpf_devs_lock); + offload = prog->aux->offload; + offmap = map_to_offmap(map); + + ret = offload && offload->netdev == offmap->netdev; + up_read(&bpf_devs_lock); + + return ret; +} + +static void bpf_offload_orphan_all_progs(struct net_device *netdev) +{ + struct bpf_prog_offload *offload, *tmp; + + list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs, offloads) + if (offload->netdev == netdev) + __bpf_prog_offload_destroy(offload->prog); +} + +static void bpf_offload_orphan_all_maps(struct net_device *netdev) +{ + struct bpf_offloaded_map *offmap, *tmp; + + list_for_each_entry_safe(offmap, tmp, &bpf_map_offload_devs, offloads) + if (offmap->netdev == netdev) + __bpf_map_offload_destroy(offmap); +} + static int bpf_offload_notification(struct notifier_block *notifier, ulong event, void *ptr) { struct net_device *netdev = netdev_notifier_info_to_dev(ptr); - struct bpf_dev_offload *offload, *tmp; ASSERT_RTNL(); @@ -181,11 +518,10 @@ static int bpf_offload_notification(struct notifier_block *notifier, if (netdev->reg_state != NETREG_UNREGISTERING) break; - list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs, - offloads) { - if (offload->netdev == netdev) - __bpf_prog_offload_destroy(offload->prog); - } + down_write(&bpf_devs_lock); + bpf_offload_orphan_all_progs(netdev); + bpf_offload_orphan_all_maps(netdev); + up_write(&bpf_devs_lock); break; default: break; diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 1712d31..0314d17 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -96,14 +96,6 @@ static inline struct smap_psock *smap_psock_sk(const struct sock *sk) return rcu_dereference_sk_user_data(sk); } -/* compute the linear packet data range [data, data_end) for skb when - * sk_skb type programs are in use. - */ -static inline void bpf_compute_data_end_sk_skb(struct sk_buff *skb) -{ - TCP_SKB_CB(skb)->bpf.data_end = skb->data + skb_headlen(skb); -} - enum __sk_action { __SK_DROP = 0, __SK_PASS, @@ -521,13 +513,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr) if (!stab) return ERR_PTR(-ENOMEM); - /* mandatory map attributes */ - stab->map.map_type = attr->map_type; - stab->map.key_size = attr->key_size; - stab->map.value_size = attr->value_size; - stab->map.max_entries = attr->max_entries; - stab->map.map_flags = attr->map_flags; - stab->map.numa_node = bpf_map_attr_numa_node(attr); + bpf_map_init_from_attr(&stab->map, attr); /* make sure page count doesn't overflow */ cost = (u64) stab->map.max_entries * sizeof(struct sock *); diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index a15bc63..b0ecf43 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -88,14 +88,10 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) if (cost >= U32_MAX - PAGE_SIZE) goto free_smap; - smap->map.map_type = attr->map_type; - smap->map.key_size = attr->key_size; + bpf_map_init_from_attr(&smap->map, attr); smap->map.value_size = value_size; - smap->map.max_entries = attr->max_entries; - smap->map.map_flags = attr->map_flags; smap->n_buckets = n_buckets; smap->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT; - smap->map.numa_node = bpf_map_attr_numa_node(attr); err = bpf_map_precharge_memlock(smap->map.pages); if (err) @@ -226,9 +222,33 @@ int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) return 0; } -static int stack_map_get_next_key(struct bpf_map *map, void *key, void *next_key) +static int stack_map_get_next_key(struct bpf_map *map, void *key, + void *next_key) { - return -EINVAL; + struct bpf_stack_map *smap = container_of(map, + struct bpf_stack_map, map); + u32 id; + + WARN_ON_ONCE(!rcu_read_lock_held()); + + if (!key) { + id = 0; + } else { + id = *(u32 *)key; + if (id >= smap->n_buckets || !smap->buckets[id]) + id = 0; + else + id++; + } + + while (id < smap->n_buckets && !smap->buckets[id]) + id++; + + if (id >= smap->n_buckets) + return -ENOENT; + + *(u32 *)next_key = id; + return 0; } static int stack_map_update_elem(struct bpf_map *map, void *key, void *value, diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 5cb783f..e24aa32 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -94,18 +94,34 @@ static int check_uarg_tail_zero(void __user *uaddr, return 0; } +const struct bpf_map_ops bpf_map_offload_ops = { + .map_alloc = bpf_map_offload_map_alloc, + .map_free = bpf_map_offload_map_free, +}; + static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) { + const struct bpf_map_ops *ops; struct bpf_map *map; + int err; - if (attr->map_type >= ARRAY_SIZE(bpf_map_types) || - !bpf_map_types[attr->map_type]) + if (attr->map_type >= ARRAY_SIZE(bpf_map_types)) + return ERR_PTR(-EINVAL); + ops = bpf_map_types[attr->map_type]; + if (!ops) return ERR_PTR(-EINVAL); - map = bpf_map_types[attr->map_type]->map_alloc(attr); + if (ops->map_alloc_check) { + err = ops->map_alloc_check(attr); + if (err) + return ERR_PTR(err); + } + if (attr->map_ifindex) + ops = &bpf_map_offload_ops; + map = ops->map_alloc(attr); if (IS_ERR(map)) return map; - map->ops = bpf_map_types[attr->map_type]; + map->ops = ops; map->map_type = attr->map_type; return map; } @@ -134,6 +150,16 @@ void bpf_map_area_free(void *area) kvfree(area); } +void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr) +{ + map->map_type = attr->map_type; + map->key_size = attr->key_size; + map->value_size = attr->value_size; + map->max_entries = attr->max_entries; + map->map_flags = attr->map_flags; + map->numa_node = bpf_map_attr_numa_node(attr); +} + int bpf_map_precharge_memlock(u32 pages) { struct user_struct *user = get_current_user(); @@ -189,16 +215,25 @@ static int bpf_map_alloc_id(struct bpf_map *map) return id > 0 ? 0 : id; } -static void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) +void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) { unsigned long flags; + /* Offloaded maps are removed from the IDR store when their device + * disappears - even if someone holds an fd to them they are unusable, + * the memory is gone, all ops will fail; they are simply waiting for + * refcnt to drop to be freed. + */ + if (!map->id) + return; + if (do_idr_lock) spin_lock_irqsave(&map_idr_lock, flags); else __acquire(&map_idr_lock); idr_remove(&map_idr, map->id); + map->id = 0; if (do_idr_lock) spin_unlock_irqrestore(&map_idr_lock, flags); @@ -378,7 +413,7 @@ static int bpf_obj_name_cpy(char *dst, const char *src) return 0; } -#define BPF_MAP_CREATE_LAST_FIELD map_name +#define BPF_MAP_CREATE_LAST_FIELD map_ifindex /* called via syscall */ static int map_create(union bpf_attr *attr) { @@ -566,8 +601,10 @@ static int map_lookup_elem(union bpf_attr *attr) if (!value) goto free_key; - if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + if (bpf_map_is_dev_bound(map)) { + err = bpf_map_offload_lookup_elem(map, key, value); + } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { err = bpf_percpu_hash_copy(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_copy(map, key, value); @@ -654,7 +691,10 @@ static int map_update_elem(union bpf_attr *attr) goto free_value; /* Need to create a kthread, thus must support schedule */ - if (map->map_type == BPF_MAP_TYPE_CPUMAP) { + if (bpf_map_is_dev_bound(map)) { + err = bpf_map_offload_update_elem(map, key, value, attr->flags); + goto out; + } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) { err = map->ops->map_update_elem(map, key, value, attr->flags); goto out; } @@ -669,10 +709,7 @@ static int map_update_elem(union bpf_attr *attr) err = bpf_percpu_hash_update(map, key, value, attr->flags); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_update(map, key, value, attr->flags); - } else if (map->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || - map->map_type == BPF_MAP_TYPE_PROG_ARRAY || - map->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || - map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) { + } else if (IS_FD_ARRAY(map)) { rcu_read_lock(); err = bpf_fd_array_map_update_elem(map, f.file, key, value, attr->flags); @@ -731,6 +768,11 @@ static int map_delete_elem(union bpf_attr *attr) goto err_put; } + if (bpf_map_is_dev_bound(map)) { + err = bpf_map_offload_delete_elem(map, key); + goto out; + } + preempt_disable(); __this_cpu_inc(bpf_prog_active); rcu_read_lock(); @@ -738,7 +780,7 @@ static int map_delete_elem(union bpf_attr *attr) rcu_read_unlock(); __this_cpu_dec(bpf_prog_active); preempt_enable(); - +out: if (!err) trace_bpf_map_delete_elem(map, ufd, key); kfree(key); @@ -788,9 +830,15 @@ static int map_get_next_key(union bpf_attr *attr) if (!next_key) goto free_key; + if (bpf_map_is_dev_bound(map)) { + err = bpf_map_offload_get_next_key(map, key, next_key); + goto out; + } + rcu_read_lock(); err = map->ops->map_get_next_key(map, key, next_key); rcu_read_unlock(); +out: if (err) goto free_next_key; @@ -905,9 +953,13 @@ static int bpf_prog_alloc_id(struct bpf_prog *prog) return id > 0 ? 0 : id; } -static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) +void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) { - /* cBPF to eBPF migrations are currently not in the idr store. */ + /* cBPF to eBPF migrations are currently not in the idr store. + * Offloaded programs are removed from the store when their device + * disappears - even if someone grabs an fd to them they are unusable, + * simply waiting for refcnt to drop to be freed. + */ if (!prog->aux->id) return; @@ -917,6 +969,7 @@ static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) __acquire(&prog_idr_lock); idr_remove(&prog_idr, prog->aux->id); + prog->aux->id = 0; if (do_idr_lock) spin_unlock_bh(&prog_idr_lock); @@ -937,10 +990,16 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu) static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) { if (atomic_dec_and_test(&prog->aux->refcnt)) { + int i; + trace_bpf_prog_put_rcu(prog); /* bpf_prog_free_id() must be called first */ bpf_prog_free_id(prog, do_idr_lock); + + for (i = 0; i < prog->aux->func_cnt; i++) + bpf_prog_kallsyms_del(prog->aux->func[i]); bpf_prog_kallsyms_del(prog); + call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); } } @@ -1151,6 +1210,8 @@ static int bpf_prog_load(union bpf_attr *attr) if (!prog) return -ENOMEM; + prog->aux->offload_requested = !!attr->prog_ifindex; + err = security_bpf_prog_alloc(prog->aux); if (err) goto free_prog_nouncharge; @@ -1172,7 +1233,7 @@ static int bpf_prog_load(union bpf_attr *attr) atomic_set(&prog->aux->refcnt, 1); prog->gpl_compatible = is_gpl ? 1 : 0; - if (attr->prog_ifindex) { + if (bpf_prog_is_dev_bound(prog->aux)) { err = bpf_prog_offload_init(prog, attr); if (err) goto free_prog; @@ -1194,7 +1255,8 @@ static int bpf_prog_load(union bpf_attr *attr) goto free_used_maps; /* eBPF program is ready to be JITed */ - prog = bpf_prog_select_runtime(prog, &err); + if (!prog->bpf_func) + prog = bpf_prog_select_runtime(prog, &err); if (err < 0) goto free_used_maps; @@ -1439,6 +1501,8 @@ static int bpf_prog_test_run(const union bpf_attr *attr, struct bpf_prog *prog; int ret = -ENOTSUPP; + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; if (CHECK_ATTR(BPF_PROG_TEST_RUN)) return -EINVAL; @@ -1551,6 +1615,67 @@ static int bpf_map_get_fd_by_id(const union bpf_attr *attr) return fd; } +static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog, + unsigned long addr) +{ + int i; + + for (i = 0; i < prog->aux->used_map_cnt; i++) + if (prog->aux->used_maps[i] == (void *)addr) + return prog->aux->used_maps[i]; + return NULL; +} + +static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog) +{ + const struct bpf_map *map; + struct bpf_insn *insns; + u64 imm; + int i; + + insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog), + GFP_USER); + if (!insns) + return insns; + + for (i = 0; i < prog->len; i++) { + if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) { + insns[i].code = BPF_JMP | BPF_CALL; + insns[i].imm = BPF_FUNC_tail_call; + /* fall-through */ + } + if (insns[i].code == (BPF_JMP | BPF_CALL) || + insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) { + if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) + insns[i].code = BPF_JMP | BPF_CALL; + if (!bpf_dump_raw_ok()) + insns[i].imm = 0; + continue; + } + + if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW)) + continue; + + imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm; + map = bpf_map_from_imm(prog, imm); + if (map) { + insns[i].src_reg = BPF_PSEUDO_MAP_FD; + insns[i].imm = map->id; + insns[i + 1].imm = 0; + continue; + } + + if (!bpf_dump_raw_ok() && + imm == (unsigned long)prog->aux) { + insns[i].imm = 0; + insns[i + 1].imm = 0; + continue; + } + } + + return insns; +} + static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, const union bpf_attr *attr, union bpf_attr __user *uattr) @@ -1598,24 +1723,51 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, goto done; } - ulen = info.jited_prog_len; - info.jited_prog_len = prog->jited_len; - if (info.jited_prog_len && ulen) { - uinsns = u64_to_user_ptr(info.jited_prog_insns); - ulen = min_t(u32, info.jited_prog_len, ulen); - if (copy_to_user(uinsns, prog->bpf_func, ulen)) - return -EFAULT; - } - ulen = info.xlated_prog_len; info.xlated_prog_len = bpf_prog_insn_size(prog); if (info.xlated_prog_len && ulen) { + struct bpf_insn *insns_sanitized; + bool fault; + + if (prog->blinded && !bpf_dump_raw_ok()) { + info.xlated_prog_insns = 0; + goto done; + } + insns_sanitized = bpf_insn_prepare_dump(prog); + if (!insns_sanitized) + return -ENOMEM; uinsns = u64_to_user_ptr(info.xlated_prog_insns); ulen = min_t(u32, info.xlated_prog_len, ulen); - if (copy_to_user(uinsns, prog->insnsi, ulen)) + fault = copy_to_user(uinsns, insns_sanitized, ulen); + kfree(insns_sanitized); + if (fault) return -EFAULT; } + if (bpf_prog_is_dev_bound(prog->aux)) { + err = bpf_prog_offload_info_fill(&info, prog); + if (err) + return err; + goto done; + } + + /* NOTE: the following code is supposed to be skipped for offload. + * bpf_prog_offload_info_fill() is the place to fill similar fields + * for offload. + */ + ulen = info.jited_prog_len; + info.jited_prog_len = prog->jited_len; + if (info.jited_prog_len && ulen) { + if (bpf_dump_raw_ok()) { + uinsns = u64_to_user_ptr(info.jited_prog_insns); + ulen = min_t(u32, info.jited_prog_len, ulen); + if (copy_to_user(uinsns, prog->bpf_func, ulen)) + return -EFAULT; + } else { + info.jited_prog_insns = 0; + } + } + done: if (copy_to_user(uinfo, &info, info_len) || put_user(info_len, &uattr->info.info_len)) @@ -1646,6 +1798,12 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map, info.map_flags = map->map_flags; memcpy(info.name, map->name, sizeof(map->name)); + if (bpf_map_is_dev_bound(map)) { + err = bpf_map_offload_info_fill(&info, map); + if (err) + return err; + } + if (copy_to_user(uinfo, &info, info_len) || put_user(info_len, &uattr->info.info_len)) return -EFAULT; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 13551e6..5fb69a8 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20,6 +20,8 @@ #include <linux/file.h> #include <linux/vmalloc.h> #include <linux/stringify.h> +#include <linux/bsearch.h> +#include <linux/sort.h> #include "disasm.h" @@ -167,11 +169,11 @@ struct bpf_call_arg_meta { static DEFINE_MUTEX(bpf_verifier_lock); /* log_level controls verbosity level of eBPF verifier. - * verbose() is used to dump the verification trace to the log, so the user - * can figure out what's wrong with the program + * bpf_verifier_log_write() is used to dump the verification trace to the log, + * so the user can figure out what's wrong with the program */ -static __printf(2, 3) void verbose(struct bpf_verifier_env *env, - const char *fmt, ...) +__printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env, + const char *fmt, ...) { struct bpf_verifer_log *log = &env->log; unsigned int n; @@ -195,6 +197,14 @@ static __printf(2, 3) void verbose(struct bpf_verifier_env *env, else log->ubuf = NULL; } +EXPORT_SYMBOL_GPL(bpf_verifier_log_write); +/* Historically bpf_verifier_log_write was called verbose, but the name was too + * generic for symbol export. The function was renamed, but not the calls in + * the verifier to avoid complicating backports. Hence the alias below. + */ +static __printf(2, 3) void verbose(struct bpf_verifier_env *env, + const char *fmt, ...) + __attribute__((alias("bpf_verifier_log_write"))); static bool type_is_pkt_pointer(enum bpf_reg_type type) { @@ -216,23 +226,48 @@ static const char * const reg_type_str[] = { [PTR_TO_PACKET_END] = "pkt_end", }; +static void print_liveness(struct bpf_verifier_env *env, + enum bpf_reg_liveness live) +{ + if (live & (REG_LIVE_READ | REG_LIVE_WRITTEN)) + verbose(env, "_"); + if (live & REG_LIVE_READ) + verbose(env, "r"); + if (live & REG_LIVE_WRITTEN) + verbose(env, "w"); +} + +static struct bpf_func_state *func(struct bpf_verifier_env *env, + const struct bpf_reg_state *reg) +{ + struct bpf_verifier_state *cur = env->cur_state; + + return cur->frame[reg->frameno]; +} + static void print_verifier_state(struct bpf_verifier_env *env, - struct bpf_verifier_state *state) + const struct bpf_func_state *state) { - struct bpf_reg_state *reg; + const struct bpf_reg_state *reg; enum bpf_reg_type t; int i; + if (state->frameno) + verbose(env, " frame%d:", state->frameno); for (i = 0; i < MAX_BPF_REG; i++) { reg = &state->regs[i]; t = reg->type; if (t == NOT_INIT) continue; - verbose(env, " R%d=%s", i, reg_type_str[t]); + verbose(env, " R%d", i); + print_liveness(env, reg->live); + verbose(env, "=%s", reg_type_str[t]); if ((t == SCALAR_VALUE || t == PTR_TO_STACK) && tnum_is_const(reg->var_off)) { /* reg->off should be 0 for SCALAR_VALUE */ verbose(env, "%lld", reg->var_off.value + reg->off); + if (t == PTR_TO_STACK) + verbose(env, ",call_%d", func(env, reg)->callsite); } else { verbose(env, "(id=%d", reg->id); if (t != SCALAR_VALUE) @@ -277,16 +312,21 @@ static void print_verifier_state(struct bpf_verifier_env *env, } } for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] == STACK_SPILL) - verbose(env, " fp%d=%s", - -MAX_BPF_STACK + i * BPF_REG_SIZE, + if (state->stack[i].slot_type[0] == STACK_SPILL) { + verbose(env, " fp%d", + (-i - 1) * BPF_REG_SIZE); + print_liveness(env, state->stack[i].spilled_ptr.live); + verbose(env, "=%s", reg_type_str[state->stack[i].spilled_ptr.type]); + } + if (state->stack[i].slot_type[0] == STACK_ZERO) + verbose(env, " fp%d=0", (-i - 1) * BPF_REG_SIZE); } verbose(env, "\n"); } -static int copy_stack_state(struct bpf_verifier_state *dst, - const struct bpf_verifier_state *src) +static int copy_stack_state(struct bpf_func_state *dst, + const struct bpf_func_state *src) { if (!src->stack) return 0; @@ -302,13 +342,13 @@ static int copy_stack_state(struct bpf_verifier_state *dst, /* do_check() starts with zero-sized stack in struct bpf_verifier_state to * make it consume minimal amount of memory. check_stack_write() access from - * the program calls into realloc_verifier_state() to grow the stack size. + * the program calls into realloc_func_state() to grow the stack size. * Note there is a non-zero 'parent' pointer inside bpf_verifier_state * which this function copies over. It points to previous bpf_verifier_state * which is never reallocated */ -static int realloc_verifier_state(struct bpf_verifier_state *state, int size, - bool copy_old) +static int realloc_func_state(struct bpf_func_state *state, int size, + bool copy_old) { u32 old_size = state->allocated_stack; struct bpf_stack_state *new_stack; @@ -341,10 +381,23 @@ static int realloc_verifier_state(struct bpf_verifier_state *state, int size, return 0; } +static void free_func_state(struct bpf_func_state *state) +{ + if (!state) + return; + kfree(state->stack); + kfree(state); +} + static void free_verifier_state(struct bpf_verifier_state *state, bool free_self) { - kfree(state->stack); + int i; + + for (i = 0; i <= state->curframe; i++) { + free_func_state(state->frame[i]); + state->frame[i] = NULL; + } if (free_self) kfree(state); } @@ -352,18 +405,46 @@ static void free_verifier_state(struct bpf_verifier_state *state, /* copy verifier state from src to dst growing dst stack space * when necessary to accommodate larger src stack */ -static int copy_verifier_state(struct bpf_verifier_state *dst, - const struct bpf_verifier_state *src) +static int copy_func_state(struct bpf_func_state *dst, + const struct bpf_func_state *src) { int err; - err = realloc_verifier_state(dst, src->allocated_stack, false); + err = realloc_func_state(dst, src->allocated_stack, false); if (err) return err; - memcpy(dst, src, offsetof(struct bpf_verifier_state, allocated_stack)); + memcpy(dst, src, offsetof(struct bpf_func_state, allocated_stack)); return copy_stack_state(dst, src); } +static int copy_verifier_state(struct bpf_verifier_state *dst_state, + const struct bpf_verifier_state *src) +{ + struct bpf_func_state *dst; + int i, err; + + /* if dst has more stack frames then src frame, free them */ + for (i = src->curframe + 1; i <= dst_state->curframe; i++) { + free_func_state(dst_state->frame[i]); + dst_state->frame[i] = NULL; + } + dst_state->curframe = src->curframe; + dst_state->parent = src->parent; + for (i = 0; i <= src->curframe; i++) { + dst = dst_state->frame[i]; + if (!dst) { + dst = kzalloc(sizeof(*dst), GFP_KERNEL); + if (!dst) + return -ENOMEM; + dst_state->frame[i] = dst; + } + err = copy_func_state(dst, src->frame[i]); + if (err) + return err; + } + return 0; +} + static int pop_stack(struct bpf_verifier_env *env, int *prev_insn_idx, int *insn_idx) { @@ -416,6 +497,8 @@ static struct bpf_verifier_state *push_stack(struct bpf_verifier_env *env, } return &elem->st; err: + free_verifier_state(env->cur_state, true); + env->cur_state = NULL; /* pop all elements and return */ while (!pop_stack(env, NULL, NULL)); return NULL; @@ -425,6 +508,10 @@ err: static const int caller_saved[CALLER_SAVED_REGS] = { BPF_REG_0, BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4, BPF_REG_5 }; +#define CALLEE_SAVED_REGS 5 +static const int callee_saved[CALLEE_SAVED_REGS] = { + BPF_REG_6, BPF_REG_7, BPF_REG_8, BPF_REG_9 +}; static void __mark_reg_not_init(struct bpf_reg_state *reg); @@ -449,6 +536,13 @@ static void __mark_reg_known_zero(struct bpf_reg_state *reg) __mark_reg_known(reg, 0); } +static void __mark_reg_const_zero(struct bpf_reg_state *reg) +{ + __mark_reg_known(reg, 0); + reg->off = 0; + reg->type = SCALAR_VALUE; +} + static void mark_reg_known_zero(struct bpf_verifier_env *env, struct bpf_reg_state *regs, u32 regno) { @@ -560,6 +654,7 @@ static void __mark_reg_unknown(struct bpf_reg_state *reg) reg->id = 0; reg->off = 0; reg->var_off = tnum_unknown; + reg->frameno = 0; __mark_reg_unbounded(reg); } @@ -568,8 +663,8 @@ static void mark_reg_unknown(struct bpf_verifier_env *env, { if (WARN_ON(regno >= MAX_BPF_REG)) { verbose(env, "mark_reg_unknown(regs, %u)\n", regno); - /* Something bad happened, let's kill all regs */ - for (regno = 0; regno < MAX_BPF_REG; regno++) + /* Something bad happened, let's kill all regs except FP */ + for (regno = 0; regno < BPF_REG_FP; regno++) __mark_reg_not_init(regs + regno); return; } @@ -587,8 +682,8 @@ static void mark_reg_not_init(struct bpf_verifier_env *env, { if (WARN_ON(regno >= MAX_BPF_REG)) { verbose(env, "mark_reg_not_init(regs, %u)\n", regno); - /* Something bad happened, let's kill all regs */ - for (regno = 0; regno < MAX_BPF_REG; regno++) + /* Something bad happened, let's kill all regs except FP */ + for (regno = 0; regno < BPF_REG_FP; regno++) __mark_reg_not_init(regs + regno); return; } @@ -596,8 +691,9 @@ static void mark_reg_not_init(struct bpf_verifier_env *env, } static void init_reg_state(struct bpf_verifier_env *env, - struct bpf_reg_state *regs) + struct bpf_func_state *state) { + struct bpf_reg_state *regs = state->regs; int i; for (i = 0; i < MAX_BPF_REG; i++) { @@ -608,41 +704,218 @@ static void init_reg_state(struct bpf_verifier_env *env, /* frame pointer */ regs[BPF_REG_FP].type = PTR_TO_STACK; mark_reg_known_zero(env, regs, BPF_REG_FP); + regs[BPF_REG_FP].frameno = state->frameno; /* 1st arg to a function */ regs[BPF_REG_1].type = PTR_TO_CTX; mark_reg_known_zero(env, regs, BPF_REG_1); } +#define BPF_MAIN_FUNC (-1) +static void init_func_state(struct bpf_verifier_env *env, + struct bpf_func_state *state, + int callsite, int frameno, int subprogno) +{ + state->callsite = callsite; + state->frameno = frameno; + state->subprogno = subprogno; + init_reg_state(env, state); +} + enum reg_arg_type { SRC_OP, /* register is used as source operand */ DST_OP, /* register is used as destination operand */ DST_OP_NO_MARK /* same as above, check only, don't mark */ }; -static void mark_reg_read(const struct bpf_verifier_state *state, u32 regno) +static int cmp_subprogs(const void *a, const void *b) +{ + return *(int *)a - *(int *)b; +} + +static int find_subprog(struct bpf_verifier_env *env, int off) { - struct bpf_verifier_state *parent = state->parent; + u32 *p; + + p = bsearch(&off, env->subprog_starts, env->subprog_cnt, + sizeof(env->subprog_starts[0]), cmp_subprogs); + if (!p) + return -ENOENT; + return p - env->subprog_starts; + +} + +static int add_subprog(struct bpf_verifier_env *env, int off) +{ + int insn_cnt = env->prog->len; + int ret; + + if (off >= insn_cnt || off < 0) { + verbose(env, "call to invalid destination\n"); + return -EINVAL; + } + ret = find_subprog(env, off); + if (ret >= 0) + return 0; + if (env->subprog_cnt >= BPF_MAX_SUBPROGS) { + verbose(env, "too many subprograms\n"); + return -E2BIG; + } + env->subprog_starts[env->subprog_cnt++] = off; + sort(env->subprog_starts, env->subprog_cnt, + sizeof(env->subprog_starts[0]), cmp_subprogs, NULL); + return 0; +} + +static int check_subprogs(struct bpf_verifier_env *env) +{ + int i, ret, subprog_start, subprog_end, off, cur_subprog = 0; + struct bpf_insn *insn = env->prog->insnsi; + int insn_cnt = env->prog->len; + + /* determine subprog starts. The end is one before the next starts */ + for (i = 0; i < insn_cnt; i++) { + if (insn[i].code != (BPF_JMP | BPF_CALL)) + continue; + if (insn[i].src_reg != BPF_PSEUDO_CALL) + continue; + if (!env->allow_ptr_leaks) { + verbose(env, "function calls to other bpf functions are allowed for root only\n"); + return -EPERM; + } + if (bpf_prog_is_dev_bound(env->prog->aux)) { + verbose(env, "function calls in offloaded programs are not supported yet\n"); + return -EINVAL; + } + ret = add_subprog(env, i + insn[i].imm + 1); + if (ret < 0) + return ret; + } + + if (env->log.level > 1) + for (i = 0; i < env->subprog_cnt; i++) + verbose(env, "func#%d @%d\n", i, env->subprog_starts[i]); + + /* now check that all jumps are within the same subprog */ + subprog_start = 0; + if (env->subprog_cnt == cur_subprog) + subprog_end = insn_cnt; + else + subprog_end = env->subprog_starts[cur_subprog++]; + for (i = 0; i < insn_cnt; i++) { + u8 code = insn[i].code; + + if (BPF_CLASS(code) != BPF_JMP) + goto next; + if (BPF_OP(code) == BPF_EXIT || BPF_OP(code) == BPF_CALL) + goto next; + off = i + insn[i].off + 1; + if (off < subprog_start || off >= subprog_end) { + verbose(env, "jump out of range from insn %d to %d\n", i, off); + return -EINVAL; + } +next: + if (i == subprog_end - 1) { + /* to avoid fall-through from one subprog into another + * the last insn of the subprog should be either exit + * or unconditional jump back + */ + if (code != (BPF_JMP | BPF_EXIT) && + code != (BPF_JMP | BPF_JA)) { + verbose(env, "last insn is not an exit or jmp\n"); + return -EINVAL; + } + subprog_start = subprog_end; + if (env->subprog_cnt == cur_subprog) + subprog_end = insn_cnt; + else + subprog_end = env->subprog_starts[cur_subprog++]; + } + } + return 0; +} + +static +struct bpf_verifier_state *skip_callee(struct bpf_verifier_env *env, + const struct bpf_verifier_state *state, + struct bpf_verifier_state *parent, + u32 regno) +{ + struct bpf_verifier_state *tmp = NULL; + + /* 'parent' could be a state of caller and + * 'state' could be a state of callee. In such case + * parent->curframe < state->curframe + * and it's ok for r1 - r5 registers + * + * 'parent' could be a callee's state after it bpf_exit-ed. + * In such case parent->curframe > state->curframe + * and it's ok for r0 only + */ + if (parent->curframe == state->curframe || + (parent->curframe < state->curframe && + regno >= BPF_REG_1 && regno <= BPF_REG_5) || + (parent->curframe > state->curframe && + regno == BPF_REG_0)) + return parent; + + if (parent->curframe > state->curframe && + regno >= BPF_REG_6) { + /* for callee saved regs we have to skip the whole chain + * of states that belong to callee and mark as LIVE_READ + * the registers before the call + */ + tmp = parent; + while (tmp && tmp->curframe != state->curframe) { + tmp = tmp->parent; + } + if (!tmp) + goto bug; + parent = tmp; + } else { + goto bug; + } + return parent; +bug: + verbose(env, "verifier bug regno %d tmp %p\n", regno, tmp); + verbose(env, "regno %d parent frame %d current frame %d\n", + regno, parent->curframe, state->curframe); + return NULL; +} + +static int mark_reg_read(struct bpf_verifier_env *env, + const struct bpf_verifier_state *state, + struct bpf_verifier_state *parent, + u32 regno) +{ + bool writes = parent == state->parent; /* Observe write marks */ if (regno == BPF_REG_FP) /* We don't need to worry about FP liveness because it's read-only */ - return; + return 0; while (parent) { /* if read wasn't screened by an earlier write ... */ - if (state->regs[regno].live & REG_LIVE_WRITTEN) + if (writes && state->frame[state->curframe]->regs[regno].live & REG_LIVE_WRITTEN) break; + parent = skip_callee(env, state, parent, regno); + if (!parent) + return -EFAULT; /* ... then we depend on parent's value */ - parent->regs[regno].live |= REG_LIVE_READ; + parent->frame[parent->curframe]->regs[regno].live |= REG_LIVE_READ; state = parent; parent = state->parent; + writes = true; } + return 0; } static int check_reg_arg(struct bpf_verifier_env *env, u32 regno, enum reg_arg_type t) { - struct bpf_reg_state *regs = env->cur_state->regs; + struct bpf_verifier_state *vstate = env->cur_state; + struct bpf_func_state *state = vstate->frame[vstate->curframe]; + struct bpf_reg_state *regs = state->regs; if (regno >= MAX_BPF_REG) { verbose(env, "R%d is invalid\n", regno); @@ -655,7 +928,7 @@ static int check_reg_arg(struct bpf_verifier_env *env, u32 regno, verbose(env, "R%d !read_ok\n", regno); return -EACCES; } - mark_reg_read(env->cur_state, regno); + return mark_reg_read(env, vstate, vstate->parent, regno); } else { /* check whether register used as dest operand can be written to */ if (regno == BPF_REG_FP) { @@ -686,17 +959,25 @@ static bool is_spillable_regtype(enum bpf_reg_type type) } } +/* Does this register contain a constant zero? */ +static bool register_is_null(struct bpf_reg_state *reg) +{ + return reg->type == SCALAR_VALUE && tnum_equals_const(reg->var_off, 0); +} + /* check_stack_read/write functions track spill/fill of registers, * stack boundary and alignment are checked in check_mem_access() */ static int check_stack_write(struct bpf_verifier_env *env, - struct bpf_verifier_state *state, int off, - int size, int value_regno) + struct bpf_func_state *state, /* func where register points to */ + int off, int size, int value_regno) { + struct bpf_func_state *cur; /* state of the current function */ int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err; + enum bpf_reg_type type; - err = realloc_verifier_state(state, round_up(slot + 1, BPF_REG_SIZE), - true); + err = realloc_func_state(state, round_up(slot + 1, BPF_REG_SIZE), + true); if (err) return err; /* caller checked that off % size == 0 and -MAX_BPF_STACK <= off < 0, @@ -709,8 +990,9 @@ static int check_stack_write(struct bpf_verifier_env *env, return -EACCES; } + cur = env->cur_state->frame[env->cur_state->curframe]; if (value_regno >= 0 && - is_spillable_regtype(state->regs[value_regno].type)) { + is_spillable_regtype((type = cur->regs[value_regno].type))) { /* register containing pointer is being spilled into stack */ if (size != BPF_REG_SIZE) { @@ -718,51 +1000,116 @@ static int check_stack_write(struct bpf_verifier_env *env, return -EACCES; } + if (state != cur && type == PTR_TO_STACK) { + verbose(env, "cannot spill pointers to stack into stack frame of the caller\n"); + return -EINVAL; + } + /* save register state */ - state->stack[spi].spilled_ptr = state->regs[value_regno]; + state->stack[spi].spilled_ptr = cur->regs[value_regno]; state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN; for (i = 0; i < BPF_REG_SIZE; i++) state->stack[spi].slot_type[i] = STACK_SPILL; } else { + u8 type = STACK_MISC; + /* regular write of data into stack */ state->stack[spi].spilled_ptr = (struct bpf_reg_state) {}; + /* only mark the slot as written if all 8 bytes were written + * otherwise read propagation may incorrectly stop too soon + * when stack slots are partially written. + * This heuristic means that read propagation will be + * conservative, since it will add reg_live_read marks + * to stack slots all the way to first state when programs + * writes+reads less than 8 bytes + */ + if (size == BPF_REG_SIZE) + state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN; + + /* when we zero initialize stack slots mark them as such */ + if (value_regno >= 0 && + register_is_null(&cur->regs[value_regno])) + type = STACK_ZERO; + for (i = 0; i < size; i++) state->stack[spi].slot_type[(slot - i) % BPF_REG_SIZE] = - STACK_MISC; + type; } return 0; } -static void mark_stack_slot_read(const struct bpf_verifier_state *state, int slot) +/* registers of every function are unique and mark_reg_read() propagates + * the liveness in the following cases: + * - from callee into caller for R1 - R5 that were used as arguments + * - from caller into callee for R0 that used as result of the call + * - from caller to the same caller skipping states of the callee for R6 - R9, + * since R6 - R9 are callee saved by implicit function prologue and + * caller's R6 != callee's R6, so when we propagate liveness up to + * parent states we need to skip callee states for R6 - R9. + * + * stack slot marking is different, since stacks of caller and callee are + * accessible in both (since caller can pass a pointer to caller's stack to + * callee which can pass it to another function), hence mark_stack_slot_read() + * has to propagate the stack liveness to all parent states at given frame number. + * Consider code: + * f1() { + * ptr = fp - 8; + * *ptr = ctx; + * call f2 { + * .. = *ptr; + * } + * .. = *ptr; + * } + * First *ptr is reading from f1's stack and mark_stack_slot_read() has + * to mark liveness at the f1's frame and not f2's frame. + * Second *ptr is also reading from f1's stack and mark_stack_slot_read() has + * to propagate liveness to f2 states at f1's frame level and further into + * f1 states at f1's frame level until write into that stack slot + */ +static void mark_stack_slot_read(struct bpf_verifier_env *env, + const struct bpf_verifier_state *state, + struct bpf_verifier_state *parent, + int slot, int frameno) { - struct bpf_verifier_state *parent = state->parent; + bool writes = parent == state->parent; /* Observe write marks */ while (parent) { + if (parent->frame[frameno]->allocated_stack <= slot * BPF_REG_SIZE) + /* since LIVE_WRITTEN mark is only done for full 8-byte + * write the read marks are conservative and parent + * state may not even have the stack allocated. In such case + * end the propagation, since the loop reached beginning + * of the function + */ + break; /* if read wasn't screened by an earlier write ... */ - if (state->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN) + if (writes && state->frame[frameno]->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN) break; /* ... then we depend on parent's value */ - parent->stack[slot].spilled_ptr.live |= REG_LIVE_READ; + parent->frame[frameno]->stack[slot].spilled_ptr.live |= REG_LIVE_READ; state = parent; parent = state->parent; + writes = true; } } static int check_stack_read(struct bpf_verifier_env *env, - struct bpf_verifier_state *state, int off, int size, - int value_regno) + struct bpf_func_state *reg_state /* func where register points to */, + int off, int size, int value_regno) { + struct bpf_verifier_state *vstate = env->cur_state; + struct bpf_func_state *state = vstate->frame[vstate->curframe]; int i, slot = -off - 1, spi = slot / BPF_REG_SIZE; u8 *stype; - if (state->allocated_stack <= slot) { + if (reg_state->allocated_stack <= slot) { verbose(env, "invalid read from stack off %d+0 size %d\n", off, size); return -EACCES; } - stype = state->stack[spi].slot_type; + stype = reg_state->stack[spi].slot_type; if (stype[0] == STACK_SPILL) { if (size != BPF_REG_SIZE) { @@ -778,21 +1125,44 @@ static int check_stack_read(struct bpf_verifier_env *env, if (value_regno >= 0) { /* restore register state from stack */ - state->regs[value_regno] = state->stack[spi].spilled_ptr; - mark_stack_slot_read(state, spi); + state->regs[value_regno] = reg_state->stack[spi].spilled_ptr; + /* mark reg as written since spilled pointer state likely + * has its liveness marks cleared by is_state_visited() + * which resets stack/reg liveness for state transitions + */ + state->regs[value_regno].live |= REG_LIVE_WRITTEN; } + mark_stack_slot_read(env, vstate, vstate->parent, spi, + reg_state->frameno); return 0; } else { + int zeros = 0; + for (i = 0; i < size; i++) { - if (stype[(slot - i) % BPF_REG_SIZE] != STACK_MISC) { - verbose(env, "invalid read from stack off %d+%d size %d\n", - off, i, size); - return -EACCES; + if (stype[(slot - i) % BPF_REG_SIZE] == STACK_MISC) + continue; + if (stype[(slot - i) % BPF_REG_SIZE] == STACK_ZERO) { + zeros++; + continue; + } + verbose(env, "invalid read from stack off %d+%d size %d\n", + off, i, size); + return -EACCES; + } + mark_stack_slot_read(env, vstate, vstate->parent, spi, + reg_state->frameno); + if (value_regno >= 0) { + if (zeros == size) { + /* any size read into register is zero extended, + * so the whole register == const_zero + */ + __mark_reg_const_zero(&state->regs[value_regno]); + } else { + /* have read misc data from the stack */ + mark_reg_unknown(env, state->regs, value_regno); } + state->regs[value_regno].live |= REG_LIVE_WRITTEN; } - if (value_regno >= 0) - /* have read misc data from the stack */ - mark_reg_unknown(env, state->regs, value_regno); return 0; } } @@ -817,7 +1187,8 @@ static int __check_map_access(struct bpf_verifier_env *env, u32 regno, int off, static int check_map_access(struct bpf_verifier_env *env, u32 regno, int off, int size, bool zero_size_allowed) { - struct bpf_verifier_state *state = env->cur_state; + struct bpf_verifier_state *vstate = env->cur_state; + struct bpf_func_state *state = vstate->frame[vstate->curframe]; struct bpf_reg_state *reg = &state->regs[regno]; int err; @@ -1079,6 +1450,103 @@ static int check_ptr_alignment(struct bpf_verifier_env *env, strict); } +static int update_stack_depth(struct bpf_verifier_env *env, + const struct bpf_func_state *func, + int off) +{ + u16 stack = env->subprog_stack_depth[func->subprogno]; + + if (stack >= -off) + return 0; + + /* update known max for given subprogram */ + env->subprog_stack_depth[func->subprogno] = -off; + return 0; +} + +/* starting from main bpf function walk all instructions of the function + * and recursively walk all callees that given function can call. + * Ignore jump and exit insns. + * Since recursion is prevented by check_cfg() this algorithm + * only needs a local stack of MAX_CALL_FRAMES to remember callsites + */ +static int check_max_stack_depth(struct bpf_verifier_env *env) +{ + int depth = 0, frame = 0, subprog = 0, i = 0, subprog_end; + struct bpf_insn *insn = env->prog->insnsi; + int insn_cnt = env->prog->len; + int ret_insn[MAX_CALL_FRAMES]; + int ret_prog[MAX_CALL_FRAMES]; + +process_func: + /* round up to 32-bytes, since this is granularity + * of interpreter stack size + */ + depth += round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32); + if (depth > MAX_BPF_STACK) { + verbose(env, "combined stack size of %d calls is %d. Too large\n", + frame + 1, depth); + return -EACCES; + } +continue_func: + if (env->subprog_cnt == subprog) + subprog_end = insn_cnt; + else + subprog_end = env->subprog_starts[subprog]; + for (; i < subprog_end; i++) { + if (insn[i].code != (BPF_JMP | BPF_CALL)) + continue; + if (insn[i].src_reg != BPF_PSEUDO_CALL) + continue; + /* remember insn and function to return to */ + ret_insn[frame] = i + 1; + ret_prog[frame] = subprog; + + /* find the callee */ + i = i + insn[i].imm + 1; + subprog = find_subprog(env, i); + if (subprog < 0) { + WARN_ONCE(1, "verifier bug. No program starts at insn %d\n", + i); + return -EFAULT; + } + subprog++; + frame++; + if (frame >= MAX_CALL_FRAMES) { + WARN_ONCE(1, "verifier bug. Call stack is too deep\n"); + return -EFAULT; + } + goto process_func; + } + /* end of for() loop means the last insn of the 'subprog' + * was reached. Doesn't matter whether it was JA or EXIT + */ + if (frame == 0) + return 0; + depth -= round_up(max_t(u32, env->subprog_stack_depth[subprog], 1), 32); + frame--; + i = ret_insn[frame]; + subprog = ret_prog[frame]; + goto continue_func; +} + +#ifndef CONFIG_BPF_JIT_ALWAYS_ON +static int get_callee_stack_depth(struct bpf_verifier_env *env, + const struct bpf_insn *insn, int idx) +{ + int start = idx + insn->imm + 1, subprog; + + subprog = find_subprog(env, start); + if (subprog < 0) { + WARN_ONCE(1, "verifier bug. No program starts at insn %d\n", + start); + return -EFAULT; + } + subprog++; + return env->subprog_stack_depth[subprog]; +} +#endif + /* truncate register to smaller size (in bytes) * must be called with size < BPF_REG_SIZE */ @@ -1112,9 +1580,9 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn int bpf_size, enum bpf_access_type t, int value_regno) { - struct bpf_verifier_state *state = env->cur_state; struct bpf_reg_state *regs = cur_regs(env); struct bpf_reg_state *reg = regs + regno; + struct bpf_func_state *state; int size, err = 0; size = bpf_size_to_bytes(bpf_size); @@ -1203,8 +1671,10 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn return -EACCES; } - if (env->prog->aux->stack_depth < -off) - env->prog->aux->stack_depth = -off; + state = func(env, reg); + err = update_stack_depth(env, state, off); + if (err) + return err; if (t == BPF_WRITE) err = check_stack_write(env, state, off, size, @@ -1282,12 +1752,6 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins BPF_SIZE(insn->code), BPF_WRITE, -1); } -/* Does this register contain a constant zero? */ -static bool register_is_null(struct bpf_reg_state reg) -{ - return reg.type == SCALAR_VALUE && tnum_equals_const(reg.var_off, 0); -} - /* when register 'regno' is passed into function that will read 'access_size' * bytes from that pointer, make sure that it's within stack boundary * and all elements of stack are initialized. @@ -1298,32 +1762,32 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno, int access_size, bool zero_size_allowed, struct bpf_call_arg_meta *meta) { - struct bpf_verifier_state *state = env->cur_state; - struct bpf_reg_state *regs = state->regs; + struct bpf_reg_state *reg = cur_regs(env) + regno; + struct bpf_func_state *state = func(env, reg); int off, i, slot, spi; - if (regs[regno].type != PTR_TO_STACK) { + if (reg->type != PTR_TO_STACK) { /* Allow zero-byte read from NULL, regardless of pointer type */ if (zero_size_allowed && access_size == 0 && - register_is_null(regs[regno])) + register_is_null(reg)) return 0; verbose(env, "R%d type=%s expected=%s\n", regno, - reg_type_str[regs[regno].type], + reg_type_str[reg->type], reg_type_str[PTR_TO_STACK]); return -EACCES; } /* Only allow fixed-offset stack reads */ - if (!tnum_is_const(regs[regno].var_off)) { + if (!tnum_is_const(reg->var_off)) { char tn_buf[48]; - tnum_strn(tn_buf, sizeof(tn_buf), regs[regno].var_off); + tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off); verbose(env, "invalid variable stack read R%d var_off=%s\n", regno, tn_buf); return -EACCES; } - off = regs[regno].off + regs[regno].var_off.value; + off = reg->off + reg->var_off.value; if (off >= 0 || off < -MAX_BPF_STACK || off + access_size > 0 || access_size < 0 || (access_size == 0 && !zero_size_allowed)) { verbose(env, "invalid stack type R%d off=%d access_size=%d\n", @@ -1331,9 +1795,6 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno, return -EACCES; } - if (env->prog->aux->stack_depth < -off) - env->prog->aux->stack_depth = -off; - if (meta && meta->raw_mode) { meta->access_size = access_size; meta->regno = regno; @@ -1341,17 +1802,32 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno, } for (i = 0; i < access_size; i++) { + u8 *stype; + slot = -(off + i) - 1; spi = slot / BPF_REG_SIZE; - if (state->allocated_stack <= slot || - state->stack[spi].slot_type[slot % BPF_REG_SIZE] != - STACK_MISC) { - verbose(env, "invalid indirect read from stack off %d+%d size %d\n", - off, i, access_size); - return -EACCES; + if (state->allocated_stack <= slot) + goto err; + stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE]; + if (*stype == STACK_MISC) + goto mark; + if (*stype == STACK_ZERO) { + /* helper can write anything into the stack */ + *stype = STACK_MISC; + goto mark; } +err: + verbose(env, "invalid indirect read from stack off %d+%d size %d\n", + off, i, access_size); + return -EACCES; +mark: + /* reading any byte out of 8-byte 'spill_slot' will cause + * the whole slot to be marked as 'read' + */ + mark_stack_slot_read(env, env->cur_state, env->cur_state->parent, + spi, state->frameno); } - return 0; + return update_stack_depth(env, state, off); } static int check_helper_mem_access(struct bpf_verifier_env *env, int regno, @@ -1374,6 +1850,19 @@ static int check_helper_mem_access(struct bpf_verifier_env *env, int regno, } } +static bool arg_type_is_mem_ptr(enum bpf_arg_type type) +{ + return type == ARG_PTR_TO_MEM || + type == ARG_PTR_TO_MEM_OR_NULL || + type == ARG_PTR_TO_UNINIT_MEM; +} + +static bool arg_type_is_mem_size(enum bpf_arg_type type) +{ + return type == ARG_CONST_SIZE || + type == ARG_CONST_SIZE_OR_ZERO; +} + static int check_func_arg(struct bpf_verifier_env *env, u32 regno, enum bpf_arg_type arg_type, struct bpf_call_arg_meta *meta) @@ -1423,15 +1912,13 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, expected_type = PTR_TO_CTX; if (type != expected_type) goto err_type; - } else if (arg_type == ARG_PTR_TO_MEM || - arg_type == ARG_PTR_TO_MEM_OR_NULL || - arg_type == ARG_PTR_TO_UNINIT_MEM) { + } else if (arg_type_is_mem_ptr(arg_type)) { expected_type = PTR_TO_STACK; /* One exception here. In case function allows for NULL to be * passed in as argument, it's a SCALAR_VALUE type. Final test * happens during stack boundary checking. */ - if (register_is_null(*reg) && + if (register_is_null(reg) && arg_type == ARG_PTR_TO_MEM_OR_NULL) /* final test in check_stack_boundary() */; else if (!type_is_pkt_pointer(type) && @@ -1486,25 +1973,12 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno, err = check_stack_boundary(env, regno, meta->map_ptr->value_size, false, NULL); - } else if (arg_type == ARG_CONST_SIZE || - arg_type == ARG_CONST_SIZE_OR_ZERO) { + } else if (arg_type_is_mem_size(arg_type)) { bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO); - /* bpf_xxx(..., buf, len) call will access 'len' bytes - * from stack pointer 'buf'. Check it - * note: regno == len, regno - 1 == buf - */ - if (regno == 0) { - /* kernel subsystem misconfigured verifier */ - verbose(env, - "ARG_CONST_SIZE cannot be first argument\n"); - return -EACCES; - } - /* The register is SCALAR_VALUE; the access check * happens using its boundaries. */ - if (!tnum_is_const(reg->var_off)) /* For unprivileged variable accesses, disable raw * mode so that the program is required to @@ -1604,6 +2078,10 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, case BPF_FUNC_tail_call: if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY) goto error; + if (env->subprog_cnt) { + verbose(env, "tail_calls are not allowed in programs with bpf-to-bpf calls\n"); + return -EINVAL; + } break; case BPF_FUNC_perf_event_read: case BPF_FUNC_perf_event_output: @@ -1644,7 +2122,7 @@ error: return -EINVAL; } -static int check_raw_mode(const struct bpf_func_proto *fn) +static bool check_raw_mode_ok(const struct bpf_func_proto *fn) { int count = 0; @@ -1659,15 +2137,52 @@ static int check_raw_mode(const struct bpf_func_proto *fn) if (fn->arg5_type == ARG_PTR_TO_UNINIT_MEM) count++; - return count > 1 ? -EINVAL : 0; + /* We only support one arg being in raw mode at the moment, + * which is sufficient for the helper functions we have + * right now. + */ + return count <= 1; +} + +static bool check_args_pair_invalid(enum bpf_arg_type arg_curr, + enum bpf_arg_type arg_next) +{ + return (arg_type_is_mem_ptr(arg_curr) && + !arg_type_is_mem_size(arg_next)) || + (!arg_type_is_mem_ptr(arg_curr) && + arg_type_is_mem_size(arg_next)); +} + +static bool check_arg_pair_ok(const struct bpf_func_proto *fn) +{ + /* bpf_xxx(..., buf, len) call will access 'len' + * bytes from memory 'buf'. Both arg types need + * to be paired, so make sure there's no buggy + * helper function specification. + */ + if (arg_type_is_mem_size(fn->arg1_type) || + arg_type_is_mem_ptr(fn->arg5_type) || + check_args_pair_invalid(fn->arg1_type, fn->arg2_type) || + check_args_pair_invalid(fn->arg2_type, fn->arg3_type) || + check_args_pair_invalid(fn->arg3_type, fn->arg4_type) || + check_args_pair_invalid(fn->arg4_type, fn->arg5_type)) + return false; + + return true; +} + +static int check_func_proto(const struct bpf_func_proto *fn) +{ + return check_raw_mode_ok(fn) && + check_arg_pair_ok(fn) ? 0 : -EINVAL; } /* Packet data might have moved, any old PTR_TO_PACKET[_META,_END] * are now invalid, so turn them into unknown SCALAR_VALUE. */ -static void clear_all_pkt_pointers(struct bpf_verifier_env *env) +static void __clear_all_pkt_pointers(struct bpf_verifier_env *env, + struct bpf_func_state *state) { - struct bpf_verifier_state *state = env->cur_state; struct bpf_reg_state *regs = state->regs, *reg; int i; @@ -1684,7 +2199,121 @@ static void clear_all_pkt_pointers(struct bpf_verifier_env *env) } } -static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx) +static void clear_all_pkt_pointers(struct bpf_verifier_env *env) +{ + struct bpf_verifier_state *vstate = env->cur_state; + int i; + + for (i = 0; i <= vstate->curframe; i++) + __clear_all_pkt_pointers(env, vstate->frame[i]); +} + +static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn, + int *insn_idx) +{ + struct bpf_verifier_state *state = env->cur_state; + struct bpf_func_state *caller, *callee; + int i, subprog, target_insn; + + if (state->curframe + 1 >= MAX_CALL_FRAMES) { + verbose(env, "the call stack of %d frames is too deep\n", + state->curframe + 2); + return -E2BIG; + } + + target_insn = *insn_idx + insn->imm; + subprog = find_subprog(env, target_insn + 1); + if (subprog < 0) { + verbose(env, "verifier bug. No program starts at insn %d\n", + target_insn + 1); + return -EFAULT; + } + + caller = state->frame[state->curframe]; + if (state->frame[state->curframe + 1]) { + verbose(env, "verifier bug. Frame %d already allocated\n", + state->curframe + 1); + return -EFAULT; + } + + callee = kzalloc(sizeof(*callee), GFP_KERNEL); + if (!callee) + return -ENOMEM; + state->frame[state->curframe + 1] = callee; + + /* callee cannot access r0, r6 - r9 for reading and has to write + * into its own stack before reading from it. + * callee can read/write into caller's stack + */ + init_func_state(env, callee, + /* remember the callsite, it will be used by bpf_exit */ + *insn_idx /* callsite */, + state->curframe + 1 /* frameno within this callchain */, + subprog + 1 /* subprog number within this prog */); + + /* copy r1 - r5 args that callee can access */ + for (i = BPF_REG_1; i <= BPF_REG_5; i++) + callee->regs[i] = caller->regs[i]; + + /* after the call regsiters r0 - r5 were scratched */ + for (i = 0; i < CALLER_SAVED_REGS; i++) { + mark_reg_not_init(env, caller->regs, caller_saved[i]); + check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK); + } + + /* only increment it after check_reg_arg() finished */ + state->curframe++; + + /* and go analyze first insn of the callee */ + *insn_idx = target_insn; + + if (env->log.level) { + verbose(env, "caller:\n"); + print_verifier_state(env, caller); + verbose(env, "callee:\n"); + print_verifier_state(env, callee); + } + return 0; +} + +static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx) +{ + struct bpf_verifier_state *state = env->cur_state; + struct bpf_func_state *caller, *callee; + struct bpf_reg_state *r0; + + callee = state->frame[state->curframe]; + r0 = &callee->regs[BPF_REG_0]; + if (r0->type == PTR_TO_STACK) { + /* technically it's ok to return caller's stack pointer + * (or caller's caller's pointer) back to the caller, + * since these pointers are valid. Only current stack + * pointer will be invalid as soon as function exits, + * but let's be conservative + */ + verbose(env, "cannot return stack pointer to the caller\n"); + return -EINVAL; + } + + state->curframe--; + caller = state->frame[state->curframe]; + /* return to the caller whatever r0 had in the callee */ + caller->regs[BPF_REG_0] = *r0; + + *insn_idx = callee->callsite + 1; + if (env->log.level) { + verbose(env, "returning from callee:\n"); + print_verifier_state(env, callee); + verbose(env, "to caller at %d:\n", *insn_idx); + print_verifier_state(env, caller); + } + /* clear everything in the callee */ + free_func_state(callee); + state->frame[state->curframe + 1] = NULL; + return 0; +} + +static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx) { const struct bpf_func_proto *fn = NULL; struct bpf_reg_state *regs; @@ -1701,7 +2330,6 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx) if (env->ops->get_func_proto) fn = env->ops->get_func_proto(func_id); - if (!fn) { verbose(env, "unknown func %s#%d\n", func_id_name(func_id), func_id); @@ -1725,10 +2353,7 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx) memset(&meta, 0, sizeof(meta)); meta.pkt_access = fn->pkt_access; - /* We only support one arg being in raw mode at the moment, which - * is sufficient for the helper functions we have right now. - */ - err = check_raw_mode(fn); + err = check_func_proto(fn); if (err) { verbose(env, "kernel subsystem misconfigured func %s#%d\n", func_id_name(func_id), func_id); @@ -1884,7 +2509,9 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, const struct bpf_reg_state *ptr_reg, const struct bpf_reg_state *off_reg) { - struct bpf_reg_state *regs = cur_regs(env), *dst_reg; + struct bpf_verifier_state *vstate = env->cur_state; + struct bpf_func_state *state = vstate->frame[vstate->curframe]; + struct bpf_reg_state *regs = state->regs, *dst_reg; bool known = tnum_is_const(off_reg->var_off); s64 smin_val = off_reg->smin_value, smax_val = off_reg->smax_value, smin_ptr = ptr_reg->smin_value, smax_ptr = ptr_reg->smax_value; @@ -2319,7 +2946,9 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, static int adjust_reg_min_max_vals(struct bpf_verifier_env *env, struct bpf_insn *insn) { - struct bpf_reg_state *regs = cur_regs(env), *dst_reg, *src_reg; + struct bpf_verifier_state *vstate = env->cur_state; + struct bpf_func_state *state = vstate->frame[vstate->curframe]; + struct bpf_reg_state *regs = state->regs, *dst_reg, *src_reg; struct bpf_reg_state *ptr_reg = NULL, off_reg = {0}; u8 opcode = BPF_OP(insn->code); @@ -2370,12 +2999,12 @@ static int adjust_reg_min_max_vals(struct bpf_verifier_env *env, /* Got here implies adding two SCALAR_VALUEs */ if (WARN_ON_ONCE(ptr_reg)) { - print_verifier_state(env, env->cur_state); + print_verifier_state(env, state); verbose(env, "verifier internal error: unexpected ptr_reg\n"); return -EINVAL; } if (WARN_ON(!src_reg)) { - print_verifier_state(env, env->cur_state); + print_verifier_state(env, state); verbose(env, "verifier internal error: no src_reg\n"); return -EINVAL; } @@ -2537,14 +3166,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) return 0; } -static void find_good_pkt_pointers(struct bpf_verifier_state *state, +static void find_good_pkt_pointers(struct bpf_verifier_state *vstate, struct bpf_reg_state *dst_reg, enum bpf_reg_type type, bool range_right_open) { + struct bpf_func_state *state = vstate->frame[vstate->curframe]; struct bpf_reg_state *regs = state->regs, *reg; u16 new_range; - int i; + int i, j; if (dst_reg->off < 0 || (dst_reg->off == 0 && range_right_open)) @@ -2614,12 +3244,15 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state, /* keep the maximum range already checked */ regs[i].range = max(regs[i].range, new_range); - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) - continue; - reg = &state->stack[i].spilled_ptr; - if (reg->type == type && reg->id == dst_reg->id) - reg->range = max(reg->range, new_range); + for (j = 0; j <= vstate->curframe; j++) { + state = vstate->frame[j]; + for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { + if (state->stack[i].slot_type[0] != STACK_SPILL) + continue; + reg = &state->stack[i].spilled_ptr; + if (reg->type == type && reg->id == dst_reg->id) + reg->range = max(reg->range, new_range); + } } } @@ -2857,20 +3490,24 @@ static void mark_map_reg(struct bpf_reg_state *regs, u32 regno, u32 id, /* The logic is similar to find_good_pkt_pointers(), both could eventually * be folded together at some point. */ -static void mark_map_regs(struct bpf_verifier_state *state, u32 regno, +static void mark_map_regs(struct bpf_verifier_state *vstate, u32 regno, bool is_null) { + struct bpf_func_state *state = vstate->frame[vstate->curframe]; struct bpf_reg_state *regs = state->regs; u32 id = regs[regno].id; - int i; + int i, j; for (i = 0; i < MAX_BPF_REG; i++) mark_map_reg(regs, i, id, is_null); - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] != STACK_SPILL) - continue; - mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null); + for (j = 0; j <= vstate->curframe; j++) { + state = vstate->frame[j]; + for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { + if (state->stack[i].slot_type[0] != STACK_SPILL) + continue; + mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null); + } } } @@ -2970,8 +3607,10 @@ static bool try_match_pkt_pointers(const struct bpf_insn *insn, static int check_cond_jmp_op(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx) { - struct bpf_verifier_state *other_branch, *this_branch = env->cur_state; - struct bpf_reg_state *regs = this_branch->regs, *dst_reg; + struct bpf_verifier_state *this_branch = env->cur_state; + struct bpf_verifier_state *other_branch; + struct bpf_reg_state *regs = this_branch->frame[this_branch->curframe]->regs; + struct bpf_reg_state *dst_reg, *other_branch_regs; u8 opcode = BPF_OP(insn->code); int err; @@ -3014,8 +3653,9 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, if (BPF_SRC(insn->code) == BPF_K && (opcode == BPF_JEQ || opcode == BPF_JNE) && dst_reg->type == SCALAR_VALUE && - tnum_equals_const(dst_reg->var_off, insn->imm)) { - if (opcode == BPF_JEQ) { + tnum_is_const(dst_reg->var_off)) { + if ((opcode == BPF_JEQ && dst_reg->var_off.value == insn->imm) || + (opcode == BPF_JNE && dst_reg->var_off.value != insn->imm)) { /* if (imm == imm) goto pc+off; * only follow the goto, ignore fall-through */ @@ -3033,6 +3673,7 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, other_branch = push_stack(env, *insn_idx + insn->off + 1, *insn_idx); if (!other_branch) return -EFAULT; + other_branch_regs = other_branch->frame[other_branch->curframe]->regs; /* detect if we are comparing against a constant value so we can adjust * our min/max values for our dst register. @@ -3045,22 +3686,22 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, if (dst_reg->type == SCALAR_VALUE && regs[insn->src_reg].type == SCALAR_VALUE) { if (tnum_is_const(regs[insn->src_reg].var_off)) - reg_set_min_max(&other_branch->regs[insn->dst_reg], + reg_set_min_max(&other_branch_regs[insn->dst_reg], dst_reg, regs[insn->src_reg].var_off.value, opcode); else if (tnum_is_const(dst_reg->var_off)) - reg_set_min_max_inv(&other_branch->regs[insn->src_reg], + reg_set_min_max_inv(&other_branch_regs[insn->src_reg], ®s[insn->src_reg], dst_reg->var_off.value, opcode); else if (opcode == BPF_JEQ || opcode == BPF_JNE) /* Comparing for equality, we can combine knowledge */ - reg_combine_min_max(&other_branch->regs[insn->src_reg], - &other_branch->regs[insn->dst_reg], + reg_combine_min_max(&other_branch_regs[insn->src_reg], + &other_branch_regs[insn->dst_reg], ®s[insn->src_reg], ®s[insn->dst_reg], opcode); } } else if (dst_reg->type == SCALAR_VALUE) { - reg_set_min_max(&other_branch->regs[insn->dst_reg], + reg_set_min_max(&other_branch_regs[insn->dst_reg], dst_reg, insn->imm, opcode); } @@ -3081,7 +3722,7 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, return -EACCES; } if (env->log.level) - print_verifier_state(env, this_branch); + print_verifier_state(env, this_branch->frame[this_branch->curframe]); return 0; } @@ -3166,6 +3807,18 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn) return -EINVAL; } + if (env->subprog_cnt) { + /* when program has LD_ABS insn JITs and interpreter assume + * that r1 == ctx == skb which is not the case for callees + * that can have arbitrary arguments. It's problematic + * for main prog as well since JITs would need to analyze + * all functions in order to make proper register save/restore + * decisions in the main prog. Hence disallow LD_ABS with calls + */ + verbose(env, "BPF_LD_[ABS|IND] instructions cannot be mixed with bpf-to-bpf calls\n"); + return -EINVAL; + } + if (insn->dst_reg != BPF_REG_0 || insn->off != 0 || BPF_SIZE(insn->code) == BPF_DW || (mode == BPF_ABS && insn->src_reg != BPF_REG_0)) { @@ -3342,6 +3995,10 @@ static int check_cfg(struct bpf_verifier_env *env) int ret = 0; int i, t; + ret = check_subprogs(env); + if (ret < 0) + return ret; + insn_state = kcalloc(insn_cnt, sizeof(int), GFP_KERNEL); if (!insn_state) return -ENOMEM; @@ -3374,6 +4031,14 @@ peek_stack: goto err_free; if (t + 1 < insn_cnt) env->explored_states[t + 1] = STATE_LIST_MARK; + if (insns[t].src_reg == BPF_PSEUDO_CALL) { + env->explored_states[t] = STATE_LIST_MARK; + ret = push_insn(t, t + insns[t].imm + 1, BRANCH, env); + if (ret == 1) + goto peek_stack; + else if (ret < 0) + goto err_free; + } } else if (opcode == BPF_JA) { if (BPF_SRC(insns[t].code) != BPF_K) { ret = -EINVAL; @@ -3492,11 +4157,21 @@ static bool check_ids(u32 old_id, u32 cur_id, struct idpair *idmap) static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur, struct idpair *idmap) { + bool equal; + if (!(rold->live & REG_LIVE_READ)) /* explored state didn't use this */ return true; - if (memcmp(rold, rcur, offsetof(struct bpf_reg_state, live)) == 0) + equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, frameno)) == 0; + + if (rold->type == PTR_TO_STACK) + /* two stack pointers are equal only if they're pointing to + * the same stack frame, since fp-8 in foo != fp-8 in bar + */ + return equal && rold->frameno == rcur->frameno; + + if (equal) return true; if (rold->type == NOT_INIT) @@ -3568,7 +4243,6 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur, tnum_in(rold->var_off, rcur->var_off); case PTR_TO_CTX: case CONST_PTR_TO_MAP: - case PTR_TO_STACK: case PTR_TO_PACKET_END: /* Only valid matches are exact, which memcmp() above * would have accepted @@ -3583,8 +4257,8 @@ static bool regsafe(struct bpf_reg_state *rold, struct bpf_reg_state *rcur, return false; } -static bool stacksafe(struct bpf_verifier_state *old, - struct bpf_verifier_state *cur, +static bool stacksafe(struct bpf_func_state *old, + struct bpf_func_state *cur, struct idpair *idmap) { int i, spi; @@ -3602,8 +4276,19 @@ static bool stacksafe(struct bpf_verifier_state *old, for (i = 0; i < old->allocated_stack; i++) { spi = i / BPF_REG_SIZE; + if (!(old->stack[spi].spilled_ptr.live & REG_LIVE_READ)) + /* explored state didn't use this */ + continue; + if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_INVALID) continue; + /* if old state was safe with misc data in the stack + * it will be safe with zero-initialized stack. + * The opposite is not true + */ + if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_MISC && + cur->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_ZERO) + continue; if (old->stack[spi].slot_type[i % BPF_REG_SIZE] != cur->stack[spi].slot_type[i % BPF_REG_SIZE]) /* Ex: old explored (safe) state has STACK_SPILL in @@ -3660,9 +4345,8 @@ static bool stacksafe(struct bpf_verifier_state *old, * whereas register type in current state is meaningful, it means that * the current state will reach 'bpf_exit' instruction safely */ -static bool states_equal(struct bpf_verifier_env *env, - struct bpf_verifier_state *old, - struct bpf_verifier_state *cur) +static bool func_states_equal(struct bpf_func_state *old, + struct bpf_func_state *cur) { struct idpair *idmap; bool ret = false; @@ -3686,71 +4370,72 @@ out_free: return ret; } +static bool states_equal(struct bpf_verifier_env *env, + struct bpf_verifier_state *old, + struct bpf_verifier_state *cur) +{ + int i; + + if (old->curframe != cur->curframe) + return false; + + /* for states to be equal callsites have to be the same + * and all frame states need to be equivalent + */ + for (i = 0; i <= old->curframe; i++) { + if (old->frame[i]->callsite != cur->frame[i]->callsite) + return false; + if (!func_states_equal(old->frame[i], cur->frame[i])) + return false; + } + return true; +} + /* A write screens off any subsequent reads; but write marks come from the - * straight-line code between a state and its parent. When we arrive at a - * jump target (in the first iteration of the propagate_liveness() loop), - * we didn't arrive by the straight-line code, so read marks in state must - * propagate to parent regardless of state's write marks. + * straight-line code between a state and its parent. When we arrive at an + * equivalent state (jump target or such) we didn't arrive by the straight-line + * code, so read marks in the state must propagate to the parent regardless + * of the state's write marks. That's what 'parent == state->parent' comparison + * in mark_reg_read() and mark_stack_slot_read() is for. */ -static bool do_propagate_liveness(const struct bpf_verifier_state *state, - struct bpf_verifier_state *parent) +static int propagate_liveness(struct bpf_verifier_env *env, + const struct bpf_verifier_state *vstate, + struct bpf_verifier_state *vparent) { - bool writes = parent == state->parent; /* Observe write marks */ - bool touched = false; /* any changes made? */ - int i; + int i, frame, err = 0; + struct bpf_func_state *state, *parent; - if (!parent) - return touched; + if (vparent->curframe != vstate->curframe) { + WARN(1, "propagate_live: parent frame %d current frame %d\n", + vparent->curframe, vstate->curframe); + return -EFAULT; + } /* Propagate read liveness of registers... */ BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG); /* We don't need to worry about FP liveness because it's read-only */ for (i = 0; i < BPF_REG_FP; i++) { - if (parent->regs[i].live & REG_LIVE_READ) + if (vparent->frame[vparent->curframe]->regs[i].live & REG_LIVE_READ) continue; - if (writes && (state->regs[i].live & REG_LIVE_WRITTEN)) - continue; - if (state->regs[i].live & REG_LIVE_READ) { - parent->regs[i].live |= REG_LIVE_READ; - touched = true; + if (vstate->frame[vstate->curframe]->regs[i].live & REG_LIVE_READ) { + err = mark_reg_read(env, vstate, vparent, i); + if (err) + return err; } } + /* ... and stack slots */ - for (i = 0; i < state->allocated_stack / BPF_REG_SIZE && - i < parent->allocated_stack / BPF_REG_SIZE; i++) { - if (parent->stack[i].slot_type[0] != STACK_SPILL) - continue; - if (state->stack[i].slot_type[0] != STACK_SPILL) - continue; - if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ) - continue; - if (writes && - (state->stack[i].spilled_ptr.live & REG_LIVE_WRITTEN)) - continue; - if (state->stack[i].spilled_ptr.live & REG_LIVE_READ) { - parent->stack[i].spilled_ptr.live |= REG_LIVE_READ; - touched = true; + for (frame = 0; frame <= vstate->curframe; frame++) { + state = vstate->frame[frame]; + parent = vparent->frame[frame]; + for (i = 0; i < state->allocated_stack / BPF_REG_SIZE && + i < parent->allocated_stack / BPF_REG_SIZE; i++) { + if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ) + continue; + if (state->stack[i].spilled_ptr.live & REG_LIVE_READ) + mark_stack_slot_read(env, vstate, vparent, i, frame); } } - return touched; -} - -/* "parent" is "a state from which we reach the current state", but initially - * it is not the state->parent (i.e. "the state whose straight-line code leads - * to the current state"), instead it is the state that happened to arrive at - * a (prunable) equivalent of the current state. See comment above - * do_propagate_liveness() for consequences of this. - * This function is just a more efficient way of calling mark_reg_read() or - * mark_stack_slot_read() on each reg in "parent" that is read in "state", - * though it requires that parent != state->parent in the call arguments. - */ -static void propagate_liveness(const struct bpf_verifier_state *state, - struct bpf_verifier_state *parent) -{ - while (do_propagate_liveness(state, parent)) { - /* Something changed, so we need to feed those changes onward */ - state = parent; - parent = state->parent; - } + return err; } static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) @@ -3758,7 +4443,7 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) struct bpf_verifier_state_list *new_sl; struct bpf_verifier_state_list *sl; struct bpf_verifier_state *cur = env->cur_state; - int i, err; + int i, j, err; sl = env->explored_states[insn_idx]; if (!sl) @@ -3779,7 +4464,9 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) * they'll be immediately forgotten as we're pruning * this state and will pop a new one. */ - propagate_liveness(&sl->state, cur); + err = propagate_liveness(env, &sl->state, cur); + if (err) + return err; return 1; } sl = sl->next; @@ -3787,9 +4474,10 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) /* there were no equivalent states, remember current one. * technically the current state is not proven to be safe yet, - * but it will either reach bpf_exit (which means it's safe) or - * it will be rejected. Since there are no loops, we won't be - * seeing this 'insn_idx' instruction again on the way to bpf_exit + * but it will either reach outer most bpf_exit (which means it's safe) + * or it will be rejected. Since there are no loops, we won't be + * seeing this tuple (frame[0].callsite, frame[1].callsite, .. insn_idx) + * again on the way to bpf_exit */ new_sl = kzalloc(sizeof(struct bpf_verifier_state_list), GFP_KERNEL); if (!new_sl) @@ -3813,19 +4501,15 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx) * explored_states can get read marks.) */ for (i = 0; i < BPF_REG_FP; i++) - cur->regs[i].live = REG_LIVE_NONE; - for (i = 0; i < cur->allocated_stack / BPF_REG_SIZE; i++) - if (cur->stack[i].slot_type[0] == STACK_SPILL) - cur->stack[i].spilled_ptr.live = REG_LIVE_NONE; - return 0; -} + cur->frame[cur->curframe]->regs[i].live = REG_LIVE_NONE; -static int ext_analyzer_insn_hook(struct bpf_verifier_env *env, - int insn_idx, int prev_insn_idx) -{ - if (env->dev_ops && env->dev_ops->insn_hook) - return env->dev_ops->insn_hook(env, insn_idx, prev_insn_idx); + /* all stack frames are accessible from callee, clear them all */ + for (j = 0; j <= cur->curframe; j++) { + struct bpf_func_state *frame = cur->frame[j]; + for (i = 0; i < frame->allocated_stack / BPF_REG_SIZE; i++) + frame->stack[i].spilled_ptr.live = REG_LIVE_NONE; + } return 0; } @@ -3834,7 +4518,7 @@ static int do_check(struct bpf_verifier_env *env) struct bpf_verifier_state *state; struct bpf_insn *insns = env->prog->insnsi; struct bpf_reg_state *regs; - int insn_cnt = env->prog->len; + int insn_cnt = env->prog->len, i; int insn_idx, prev_insn_idx = 0; int insn_processed = 0; bool do_print_state = false; @@ -3842,9 +4526,18 @@ static int do_check(struct bpf_verifier_env *env) state = kzalloc(sizeof(struct bpf_verifier_state), GFP_KERNEL); if (!state) return -ENOMEM; - env->cur_state = state; - init_reg_state(env, state->regs); + state->curframe = 0; state->parent = NULL; + state->frame[0] = kzalloc(sizeof(struct bpf_func_state), GFP_KERNEL); + if (!state->frame[0]) { + kfree(state); + return -ENOMEM; + } + env->cur_state = state; + init_func_state(env, state->frame[0], + BPF_MAIN_FUNC /* callsite */, + 0 /* frameno */, + 0 /* subprogno, zero == main subprog */); insn_idx = 0; for (;;) { struct bpf_insn *insn; @@ -3891,19 +4584,25 @@ static int do_check(struct bpf_verifier_env *env) else verbose(env, "\nfrom %d to %d:", prev_insn_idx, insn_idx); - print_verifier_state(env, state); + print_verifier_state(env, state->frame[state->curframe]); do_print_state = false; } if (env->log.level) { + const struct bpf_insn_cbs cbs = { + .cb_print = verbose, + }; + verbose(env, "%d: ", insn_idx); - print_bpf_insn(verbose, env, insn, - env->allow_ptr_leaks); + print_bpf_insn(&cbs, env, insn, env->allow_ptr_leaks); } - err = ext_analyzer_insn_hook(env, insn_idx, prev_insn_idx); - if (err) - return err; + if (bpf_prog_is_dev_bound(env->prog->aux)) { + err = bpf_prog_offload_verify_insn(env, insn_idx, + prev_insn_idx); + if (err) + return err; + } regs = cur_regs(env); env->insn_aux_data[insn_idx].seen = true; @@ -4030,13 +4729,17 @@ static int do_check(struct bpf_verifier_env *env) if (opcode == BPF_CALL) { if (BPF_SRC(insn->code) != BPF_K || insn->off != 0 || - insn->src_reg != BPF_REG_0 || + (insn->src_reg != BPF_REG_0 && + insn->src_reg != BPF_PSEUDO_CALL) || insn->dst_reg != BPF_REG_0) { verbose(env, "BPF_CALL uses reserved fields\n"); return -EINVAL; } - err = check_call(env, insn->imm, insn_idx); + if (insn->src_reg == BPF_PSEUDO_CALL) + err = check_func_call(env, insn, &insn_idx); + else + err = check_helper_call(env, insn->imm, insn_idx); if (err) return err; @@ -4061,6 +4764,16 @@ static int do_check(struct bpf_verifier_env *env) return -EINVAL; } + if (state->curframe) { + /* exit from nested function */ + prev_insn_idx = insn_idx; + err = prepare_func_exit(env, &insn_idx); + if (err) + return err; + do_print_state = true; + continue; + } + /* eBPF calling convetion is such that R0 is used * to return the value from eBPF program. * Make sure that it's readable at this time @@ -4121,8 +4834,17 @@ process_bpf_exit: insn_idx++; } - verbose(env, "processed %d insns, stack depth %d\n", insn_processed, - env->prog->aux->stack_depth); + verbose(env, "processed %d insns (limit %d), stack depth ", + insn_processed, BPF_COMPLEXITY_LIMIT_INSNS); + for (i = 0; i < env->subprog_cnt + 1; i++) { + u32 depth = env->subprog_stack_depth[i]; + + verbose(env, "%d", depth); + if (i + 1 < env->subprog_cnt + 1) + verbose(env, "+"); + } + verbose(env, "\n"); + env->prog->aux->stack_depth = env->subprog_stack_depth[0]; return 0; } @@ -4155,6 +4877,13 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, return -EINVAL; } } + + if ((bpf_prog_is_dev_bound(prog->aux) || bpf_map_is_dev_bound(map)) && + !bpf_offload_dev_match(prog, map)) { + verbose(env, "offload device mismatch between prog and map\n"); + return -EINVAL; + } + return 0; } @@ -4252,6 +4981,13 @@ static int replace_map_fd_with_map_ptr(struct bpf_verifier_env *env) next_insn: insn++; i++; + continue; + } + + /* Basic sanity check before we invest more work here. */ + if (!bpf_opcode_in_insntable(insn->code)) { + verbose(env, "unknown opcode %02x\n", insn->code); + return -EINVAL; } } @@ -4308,6 +5044,19 @@ static int adjust_insn_aux_data(struct bpf_verifier_env *env, u32 prog_len, return 0; } +static void adjust_subprog_starts(struct bpf_verifier_env *env, u32 off, u32 len) +{ + int i; + + if (len == 1) + return; + for (i = 0; i < env->subprog_cnt; i++) { + if (env->subprog_starts[i] < off) + continue; + env->subprog_starts[i] += len - 1; + } +} + static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 off, const struct bpf_insn *patch, u32 len) { @@ -4318,17 +5067,25 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of return NULL; if (adjust_insn_aux_data(env, new_prog->len, off, len)) return NULL; + adjust_subprog_starts(env, off, len); return new_prog; } -/* The verifier does more data flow analysis than llvm and will not explore - * branches that are dead at run time. Malicious programs can have dead code - * too. Therefore replace all dead at-run-time code with nops. +/* The verifier does more data flow analysis than llvm and will not + * explore branches that are dead at run time. Malicious programs can + * have dead code too. Therefore replace all dead at-run-time code + * with 'ja -1'. + * + * Just nops are not optimal, e.g. if they would sit at the end of the + * program and through another bug we would manage to jump there, then + * we'd execute beyond program memory otherwise. Returning exception + * code also wouldn't work since we can have subprogs where the dead + * code could be located. */ static void sanitize_dead_code(struct bpf_verifier_env *env) { struct bpf_insn_aux_data *aux_data = env->insn_aux_data; - struct bpf_insn nop = BPF_MOV64_REG(BPF_REG_0, BPF_REG_0); + struct bpf_insn trap = BPF_JMP_IMM(BPF_JA, 0, 0, -1); struct bpf_insn *insn = env->prog->insnsi; const int insn_cnt = env->prog->len; int i; @@ -4336,7 +5093,7 @@ static void sanitize_dead_code(struct bpf_verifier_env *env) for (i = 0; i < insn_cnt; i++) { if (aux_data[i].seen) continue; - memcpy(insn + i, &nop, sizeof(nop)); + memcpy(insn + i, &trap, sizeof(trap)); } } @@ -4452,6 +5209,180 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) return 0; } +static int jit_subprogs(struct bpf_verifier_env *env) +{ + struct bpf_prog *prog = env->prog, **func, *tmp; + int i, j, subprog_start, subprog_end = 0, len, subprog; + struct bpf_insn *insn; + void *old_bpf_func; + int err = -ENOMEM; + + if (env->subprog_cnt == 0) + return 0; + + for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + subprog = find_subprog(env, i + insn->imm + 1); + if (subprog < 0) { + WARN_ONCE(1, "verifier bug. No program starts at insn %d\n", + i + insn->imm + 1); + return -EFAULT; + } + /* temporarily remember subprog id inside insn instead of + * aux_data, since next loop will split up all insns into funcs + */ + insn->off = subprog + 1; + /* remember original imm in case JIT fails and fallback + * to interpreter will be needed + */ + env->insn_aux_data[i].call_imm = insn->imm; + /* point imm to __bpf_call_base+1 from JITs point of view */ + insn->imm = 1; + } + + func = kzalloc(sizeof(prog) * (env->subprog_cnt + 1), GFP_KERNEL); + if (!func) + return -ENOMEM; + + for (i = 0; i <= env->subprog_cnt; i++) { + subprog_start = subprog_end; + if (env->subprog_cnt == i) + subprog_end = prog->len; + else + subprog_end = env->subprog_starts[i]; + + len = subprog_end - subprog_start; + func[i] = bpf_prog_alloc(bpf_prog_size(len), GFP_USER); + if (!func[i]) + goto out_free; + memcpy(func[i]->insnsi, &prog->insnsi[subprog_start], + len * sizeof(struct bpf_insn)); + func[i]->type = prog->type; + func[i]->len = len; + if (bpf_prog_calc_tag(func[i])) + goto out_free; + func[i]->is_func = 1; + /* Use bpf_prog_F_tag to indicate functions in stack traces. + * Long term would need debug info to populate names + */ + func[i]->aux->name[0] = 'F'; + func[i]->aux->stack_depth = env->subprog_stack_depth[i]; + func[i]->jit_requested = 1; + func[i] = bpf_int_jit_compile(func[i]); + if (!func[i]->jited) { + err = -ENOTSUPP; + goto out_free; + } + cond_resched(); + } + /* at this point all bpf functions were successfully JITed + * now populate all bpf_calls with correct addresses and + * run last pass of JIT + */ + for (i = 0; i <= env->subprog_cnt; i++) { + insn = func[i]->insnsi; + for (j = 0; j < func[i]->len; j++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + subprog = insn->off; + insn->off = 0; + insn->imm = (u64 (*)(u64, u64, u64, u64, u64)) + func[subprog]->bpf_func - + __bpf_call_base; + } + } + for (i = 0; i <= env->subprog_cnt; i++) { + old_bpf_func = func[i]->bpf_func; + tmp = bpf_int_jit_compile(func[i]); + if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) { + verbose(env, "JIT doesn't support bpf-to-bpf calls\n"); + err = -EFAULT; + goto out_free; + } + cond_resched(); + } + + /* finally lock prog and jit images for all functions and + * populate kallsysm + */ + for (i = 0; i <= env->subprog_cnt; i++) { + bpf_prog_lock_ro(func[i]); + bpf_prog_kallsyms_add(func[i]); + } + + /* Last step: make now unused interpreter insns from main + * prog consistent for later dump requests, so they can + * later look the same as if they were interpreted only. + */ + for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) { + unsigned long addr; + + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + insn->off = env->insn_aux_data[i].call_imm; + subprog = find_subprog(env, i + insn->off + 1); + addr = (unsigned long)func[subprog + 1]->bpf_func; + addr &= PAGE_MASK; + insn->imm = (u64 (*)(u64, u64, u64, u64, u64)) + addr - __bpf_call_base; + } + + prog->jited = 1; + prog->bpf_func = func[0]->bpf_func; + prog->aux->func = func; + prog->aux->func_cnt = env->subprog_cnt + 1; + return 0; +out_free: + for (i = 0; i <= env->subprog_cnt; i++) + if (func[i]) + bpf_jit_free(func[i]); + kfree(func); + /* cleanup main prog to be interpreted */ + prog->jit_requested = 0; + for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + insn->off = 0; + insn->imm = env->insn_aux_data[i].call_imm; + } + return err; +} + +static int fixup_call_args(struct bpf_verifier_env *env) +{ +#ifndef CONFIG_BPF_JIT_ALWAYS_ON + struct bpf_prog *prog = env->prog; + struct bpf_insn *insn = prog->insnsi; + int i, depth; +#endif + int err; + + err = 0; + if (env->prog->jit_requested) { + err = jit_subprogs(env); + if (err == 0) + return 0; + } +#ifndef CONFIG_BPF_JIT_ALWAYS_ON + for (i = 0; i < prog->len; i++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + depth = get_callee_stack_depth(env, insn, i); + if (depth < 0) + return depth; + bpf_patch_call_args(insn, depth); + } + err = 0; +#endif + return err; +} + /* fixup insn->imm field of bpf_call instructions * and inline eligible helpers as explicit sequence of BPF instructions * @@ -4469,15 +5400,37 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) int i, cnt, delta = 0; for (i = 0; i < insn_cnt; i++, insn++) { - if (insn->code == (BPF_ALU | BPF_MOD | BPF_X) || + if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) || + insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) || + insn->code == (BPF_ALU | BPF_MOD | BPF_X) || insn->code == (BPF_ALU | BPF_DIV | BPF_X)) { - /* due to JIT bugs clear upper 32-bits of src register - * before div/mod operation - */ - insn_buf[0] = BPF_MOV32_REG(insn->src_reg, insn->src_reg); - insn_buf[1] = *insn; - cnt = 2; - new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt); + bool is64 = BPF_CLASS(insn->code) == BPF_ALU64; + struct bpf_insn mask_and_div[] = { + BPF_MOV32_REG(insn->src_reg, insn->src_reg), + /* Rx div 0 -> 0 */ + BPF_JMP_IMM(BPF_JNE, insn->src_reg, 0, 2), + BPF_ALU32_REG(BPF_XOR, insn->dst_reg, insn->dst_reg), + BPF_JMP_IMM(BPF_JA, 0, 0, 1), + *insn, + }; + struct bpf_insn mask_and_mod[] = { + BPF_MOV32_REG(insn->src_reg, insn->src_reg), + /* Rx mod 0 -> Rx */ + BPF_JMP_IMM(BPF_JEQ, insn->src_reg, 0, 1), + *insn, + }; + struct bpf_insn *patchlet; + + if (insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) || + insn->code == (BPF_ALU | BPF_DIV | BPF_X)) { + patchlet = mask_and_div + (is64 ? 1 : 0); + cnt = ARRAY_SIZE(mask_and_div) - (is64 ? 1 : 0); + } else { + patchlet = mask_and_mod + (is64 ? 1 : 0); + cnt = ARRAY_SIZE(mask_and_mod) - (is64 ? 1 : 0); + } + + new_prog = bpf_patch_insn_data(env, i + delta, patchlet, cnt); if (!new_prog) return -ENOMEM; @@ -4489,11 +5442,15 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) if (insn->code != (BPF_JMP | BPF_CALL)) continue; + if (insn->src_reg == BPF_PSEUDO_CALL) + continue; if (insn->imm == BPF_FUNC_get_route_realm) prog->dst_needed = 1; if (insn->imm == BPF_FUNC_get_prandom_u32) bpf_user_rnd_init_once(); + if (insn->imm == BPF_FUNC_override_return) + prog->kprobe_override = 1; if (insn->imm == BPF_FUNC_tail_call) { /* If we tail call into other programs, we * cannot make any assumptions since they can @@ -4545,7 +5502,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) /* BPF_EMIT_CALL() assumptions in some of the map_gen_lookup * handlers are currently limited to 64 bit only. */ - if (ebpf_jit_enabled() && BITS_PER_LONG == 64 && + if (prog->jit_requested && BITS_PER_LONG == 64 && insn->imm == BPF_FUNC_map_lookup_elem) { map_ptr = env->insn_aux_data[i + delta].map_ptr; if (map_ptr == BPF_MAP_PTR_POISON || @@ -4680,7 +5637,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) env->strict_alignment = true; - if (env->prog->aux->offload) { + if (bpf_prog_is_dev_bound(env->prog->aux)) { ret = bpf_prog_offload_verifier_prep(env); if (ret) goto err_unlock; @@ -4697,12 +5654,12 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) if (!env->explored_states) goto skip_full_check; + env->allow_ptr_leaks = capable(CAP_SYS_ADMIN); + ret = check_cfg(env); if (ret < 0) goto skip_full_check; - env->allow_ptr_leaks = capable(CAP_SYS_ADMIN); - ret = do_check(env); if (env->cur_state) { free_verifier_state(env->cur_state, true); @@ -4717,12 +5674,18 @@ skip_full_check: sanitize_dead_code(env); if (ret == 0) + ret = check_max_stack_depth(env); + + if (ret == 0) /* program is valid, convert *(u32*)(ctx + off) accesses */ ret = convert_ctx_accesses(env); if (ret == 0) ret = fixup_bpf_calls(env); + if (ret == 0) + ret = fixup_call_args(env); + if (log->level && bpf_verifier_log_full(log)) ret = -ENOSPC; if (log->level && !log->ubuf) { diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 7e4c445..8cda3bc 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1397,7 +1397,7 @@ static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft, cgroup_on_dfl(cgrp) ? ss->name : ss->legacy_name, cft->name); else - strlcpy(buf, cft->name, CGROUP_FILE_NAME_MAX); + strscpy(buf, cft->name, CGROUP_FILE_NAME_MAX); return buf; } @@ -1864,9 +1864,9 @@ void init_cgroup_root(struct cgroup_root *root, struct cgroup_sb_opts *opts) root->flags = opts->flags; if (opts->release_agent) - strlcpy(root->release_agent_path, opts->release_agent, PATH_MAX); + strscpy(root->release_agent_path, opts->release_agent, PATH_MAX); if (opts->name) - strlcpy(root->name, opts->name, MAX_CGROUP_ROOT_NAMELEN); + strscpy(root->name, opts->name, MAX_CGROUP_ROOT_NAMELEN); if (opts->cpuset_clone_children) set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags); } diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index c8146d5..dbb0781 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2441,7 +2441,6 @@ static int kdb_kill(int argc, const char **argv) long sig, pid; char *endp; struct task_struct *p; - struct siginfo info; if (argc != 2) return KDB_ARGCOUNT; @@ -2449,7 +2448,7 @@ static int kdb_kill(int argc, const char **argv) sig = simple_strtol(argv[1], &endp, 0); if (*endp) return KDB_BADINT; - if (sig >= 0) { + if ((sig >= 0) || !valid_signal(-sig)) { kdb_printf("Invalid signal parameter.<-signal>\n"); return 0; } @@ -2470,12 +2469,7 @@ static int kdb_kill(int argc, const char **argv) return 0; } p = p->group_leader; - info.si_signo = sig; - info.si_errno = 0; - info.si_code = SI_USER; - info.si_pid = pid; /* same capabilities as process being signalled */ - info.si_uid = 0; /* kdb has root authority */ - kdb_send_sig_info(p, &info); + kdb_send_sig(p, sig); return 0; } diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index fc224fb..1e5a502 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -208,7 +208,7 @@ extern unsigned long kdb_task_state(const struct task_struct *p, extern void kdb_ps_suppressed(void); extern void kdb_ps1(const struct task_struct *p); extern void kdb_print_nameval(const char *name, unsigned long val); -extern void kdb_send_sig_info(struct task_struct *p, struct siginfo *info); +extern void kdb_send_sig(struct task_struct *p, int sig); extern void kdb_meminfo_proc_show(void); extern char *kdb_getstr(char *, size_t, const char *); extern void kdb_gdb_state_pass(char *buf); diff --git a/kernel/events/core.c b/kernel/events/core.c index d99fe3f..f0549e7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4520,11 +4520,11 @@ perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) return ret; } -static unsigned int perf_poll(struct file *file, poll_table *wait) +static __poll_t perf_poll(struct file *file, poll_table *wait) { struct perf_event *event = file->private_data; struct ring_buffer *rb; - unsigned int events = POLLHUP; + __poll_t events = POLLHUP; poll_wait(file, &event->waitq, wait); @@ -4732,6 +4732,9 @@ static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned lon rcu_read_unlock(); return 0; } + + case PERF_EVENT_IOC_QUERY_BPF: + return perf_event_query_prog_array(event, (void __user *)arg); default: return -ENOTTY; } @@ -4913,6 +4916,7 @@ void perf_event_update_userpage(struct perf_event *event) unlock: rcu_read_unlock(); } +EXPORT_SYMBOL_GPL(perf_event_update_userpage); static int perf_mmap_fault(struct vm_fault *vmf) { @@ -8099,6 +8103,13 @@ static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) return -EINVAL; } + /* Kprobe override only works for kprobes, not uprobes. */ + if (prog->kprobe_override && + !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { + bpf_prog_put(prog); + return -EINVAL; + } + if (is_tracepoint || is_syscall_tp) { int off = trace_event_get_offsets(event->tp_event); diff --git a/kernel/fail_function.c b/kernel/fail_function.c new file mode 100644 index 0000000..21b0122 --- /dev/null +++ b/kernel/fail_function.c @@ -0,0 +1,349 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * fail_function.c: Function-based error injection + */ +#include <linux/error-injection.h> +#include <linux/debugfs.h> +#include <linux/fault-inject.h> +#include <linux/kallsyms.h> +#include <linux/kprobes.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs); + +struct fei_attr { + struct list_head list; + struct kprobe kp; + unsigned long retval; +}; +static DEFINE_MUTEX(fei_lock); +static LIST_HEAD(fei_attr_list); +static DECLARE_FAULT_ATTR(fei_fault_attr); +static struct dentry *fei_debugfs_dir; + +static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv) +{ + switch (get_injectable_error_type(addr)) { + case EI_ETYPE_NULL: + if (retv != 0) + return 0; + break; + case EI_ETYPE_ERRNO: + if (retv < (unsigned long)-MAX_ERRNO) + return (unsigned long)-EINVAL; + break; + case EI_ETYPE_ERRNO_NULL: + if (retv != 0 && retv < (unsigned long)-MAX_ERRNO) + return (unsigned long)-EINVAL; + break; + } + + return retv; +} + +static struct fei_attr *fei_attr_new(const char *sym, unsigned long addr) +{ + struct fei_attr *attr; + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (attr) { + attr->kp.symbol_name = kstrdup(sym, GFP_KERNEL); + if (!attr->kp.symbol_name) { + kfree(attr); + return NULL; + } + attr->kp.pre_handler = fei_kprobe_handler; + attr->retval = adjust_error_retval(addr, 0); + INIT_LIST_HEAD(&attr->list); + } + return attr; +} + +static void fei_attr_free(struct fei_attr *attr) +{ + if (attr) { + kfree(attr->kp.symbol_name); + kfree(attr); + } +} + +static struct fei_attr *fei_attr_lookup(const char *sym) +{ + struct fei_attr *attr; + + list_for_each_entry(attr, &fei_attr_list, list) { + if (!strcmp(attr->kp.symbol_name, sym)) + return attr; + } + + return NULL; +} + +static bool fei_attr_is_valid(struct fei_attr *_attr) +{ + struct fei_attr *attr; + + list_for_each_entry(attr, &fei_attr_list, list) { + if (attr == _attr) + return true; + } + + return false; +} + +static int fei_retval_set(void *data, u64 val) +{ + struct fei_attr *attr = data; + unsigned long retv = (unsigned long)val; + int err = 0; + + mutex_lock(&fei_lock); + /* + * Since this operation can be done after retval file is removed, + * It is safer to check the attr is still valid before accessing + * its member. + */ + if (!fei_attr_is_valid(attr)) { + err = -ENOENT; + goto out; + } + + if (attr->kp.addr) { + if (adjust_error_retval((unsigned long)attr->kp.addr, + val) != retv) + err = -EINVAL; + } + if (!err) + attr->retval = val; +out: + mutex_unlock(&fei_lock); + + return err; +} + +static int fei_retval_get(void *data, u64 *val) +{ + struct fei_attr *attr = data; + int err = 0; + + mutex_lock(&fei_lock); + /* Here we also validate @attr to ensure it still exists. */ + if (!fei_attr_is_valid(attr)) + err = -ENOENT; + else + *val = attr->retval; + mutex_unlock(&fei_lock); + + return err; +} +DEFINE_DEBUGFS_ATTRIBUTE(fei_retval_ops, fei_retval_get, fei_retval_set, + "%llx\n"); + +static int fei_debugfs_add_attr(struct fei_attr *attr) +{ + struct dentry *dir; + + dir = debugfs_create_dir(attr->kp.symbol_name, fei_debugfs_dir); + if (!dir) + return -ENOMEM; + + if (!debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops)) { + debugfs_remove_recursive(dir); + return -ENOMEM; + } + + return 0; +} + +static void fei_debugfs_remove_attr(struct fei_attr *attr) +{ + struct dentry *dir; + + dir = debugfs_lookup(attr->kp.symbol_name, fei_debugfs_dir); + if (dir) + debugfs_remove_recursive(dir); +} + +static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs) +{ + struct fei_attr *attr = container_of(kp, struct fei_attr, kp); + + if (should_fail(&fei_fault_attr, 1)) { + regs_set_return_value(regs, attr->retval); + override_function_with_return(regs); + /* Kprobe specific fixup */ + reset_current_kprobe(); + preempt_enable_no_resched(); + return 1; + } + + return 0; +} +NOKPROBE_SYMBOL(fei_kprobe_handler) + +static void *fei_seq_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&fei_lock); + return seq_list_start(&fei_attr_list, *pos); +} + +static void fei_seq_stop(struct seq_file *m, void *v) +{ + mutex_unlock(&fei_lock); +} + +static void *fei_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return seq_list_next(v, &fei_attr_list, pos); +} + +static int fei_seq_show(struct seq_file *m, void *v) +{ + struct fei_attr *attr = list_entry(v, struct fei_attr, list); + + seq_printf(m, "%pf\n", attr->kp.addr); + return 0; +} + +static const struct seq_operations fei_seq_ops = { + .start = fei_seq_start, + .next = fei_seq_next, + .stop = fei_seq_stop, + .show = fei_seq_show, +}; + +static int fei_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &fei_seq_ops); +} + +static void fei_attr_remove(struct fei_attr *attr) +{ + fei_debugfs_remove_attr(attr); + unregister_kprobe(&attr->kp); + list_del(&attr->list); + fei_attr_free(attr); +} + +static void fei_attr_remove_all(void) +{ + struct fei_attr *attr, *n; + + list_for_each_entry_safe(attr, n, &fei_attr_list, list) { + fei_attr_remove(attr); + } +} + +static ssize_t fei_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + struct fei_attr *attr; + unsigned long addr; + char *buf, *sym; + int ret; + + /* cut off if it is too long */ + if (count > KSYM_NAME_LEN) + count = KSYM_NAME_LEN; + buf = kmalloc(sizeof(char) * (count + 1), GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, buffer, count)) { + ret = -EFAULT; + goto out; + } + buf[count] = '\0'; + sym = strstrip(buf); + + mutex_lock(&fei_lock); + + /* Writing just spaces will remove all injection points */ + if (sym[0] == '\0') { + fei_attr_remove_all(); + ret = count; + goto out; + } + /* Writing !function will remove one injection point */ + if (sym[0] == '!') { + attr = fei_attr_lookup(sym + 1); + if (!attr) { + ret = -ENOENT; + goto out; + } + fei_attr_remove(attr); + ret = count; + goto out; + } + + addr = kallsyms_lookup_name(sym); + if (!addr) { + ret = -EINVAL; + goto out; + } + if (!within_error_injection_list(addr)) { + ret = -ERANGE; + goto out; + } + if (fei_attr_lookup(sym)) { + ret = -EBUSY; + goto out; + } + attr = fei_attr_new(sym, addr); + if (!attr) { + ret = -ENOMEM; + goto out; + } + + ret = register_kprobe(&attr->kp); + if (!ret) + ret = fei_debugfs_add_attr(attr); + if (ret < 0) + fei_attr_remove(attr); + else { + list_add_tail(&attr->list, &fei_attr_list); + ret = count; + } +out: + kfree(buf); + mutex_unlock(&fei_lock); + return ret; +} + +static const struct file_operations fei_ops = { + .open = fei_open, + .read = seq_read, + .write = fei_write, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init fei_debugfs_init(void) +{ + struct dentry *dir; + + dir = fault_create_debugfs_attr("fail_function", NULL, + &fei_fault_attr); + if (IS_ERR(dir)) + return PTR_ERR(dir); + + /* injectable attribute is just a symlink of error_inject/list */ + if (!debugfs_create_symlink("injectable", dir, + "../error_injection/list")) + goto error; + + if (!debugfs_create_file("inject", 0600, dir, NULL, &fei_ops)) + goto error; + + fei_debugfs_dir = dir; + + return 0; +error: + debugfs_remove_recursive(dir); + return -ENOMEM; +} + +late_initcall(fei_debugfs_init); diff --git a/kernel/fork.c b/kernel/fork.c index 2295fc6..c7c1123 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -77,6 +77,7 @@ #include <linux/blkdev.h> #include <linux/fs_struct.h> #include <linux/magic.h> +#include <linux/sched/mm.h> #include <linux/perf_event.h> #include <linux/posix-timers.h> #include <linux/user-return-notifier.h> @@ -282,8 +283,9 @@ static void free_thread_stack(struct task_struct *tsk) void thread_stack_cache_init(void) { - thread_stack_cache = kmem_cache_create("thread_stack", THREAD_SIZE, - THREAD_SIZE, 0, NULL); + thread_stack_cache = kmem_cache_create_usercopy("thread_stack", + THREAD_SIZE, THREAD_SIZE, 0, 0, + THREAD_SIZE, NULL); BUG_ON(thread_stack_cache == NULL); } # endif @@ -390,6 +392,246 @@ void free_task(struct task_struct *tsk) } EXPORT_SYMBOL(free_task); +#ifdef CONFIG_MMU +static __latent_entropy int dup_mmap(struct mm_struct *mm, + struct mm_struct *oldmm) +{ + struct vm_area_struct *mpnt, *tmp, *prev, **pprev; + struct rb_node **rb_link, *rb_parent; + int retval; + unsigned long charge; + LIST_HEAD(uf); + + uprobe_start_dup_mmap(); + if (down_write_killable(&oldmm->mmap_sem)) { + retval = -EINTR; + goto fail_uprobe_end; + } + flush_cache_dup_mm(oldmm); + uprobe_dup_mmap(oldmm, mm); + /* + * Not linked in yet - no deadlock potential: + */ + down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING); + + /* No ordering required: file already has been exposed. */ + RCU_INIT_POINTER(mm->exe_file, get_mm_exe_file(oldmm)); + + mm->total_vm = oldmm->total_vm; + mm->data_vm = oldmm->data_vm; + mm->exec_vm = oldmm->exec_vm; + mm->stack_vm = oldmm->stack_vm; + + rb_link = &mm->mm_rb.rb_node; + rb_parent = NULL; + pprev = &mm->mmap; + retval = ksm_fork(mm, oldmm); + if (retval) + goto out; + retval = khugepaged_fork(mm, oldmm); + if (retval) + goto out; + + prev = NULL; + for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { + struct file *file; + + if (mpnt->vm_flags & VM_DONTCOPY) { + vm_stat_account(mm, mpnt->vm_flags, -vma_pages(mpnt)); + continue; + } + charge = 0; + if (mpnt->vm_flags & VM_ACCOUNT) { + unsigned long len = vma_pages(mpnt); + + if (security_vm_enough_memory_mm(oldmm, len)) /* sic */ + goto fail_nomem; + charge = len; + } + tmp = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); + if (!tmp) + goto fail_nomem; + *tmp = *mpnt; + INIT_LIST_HEAD(&tmp->anon_vma_chain); + retval = vma_dup_policy(mpnt, tmp); + if (retval) + goto fail_nomem_policy; + tmp->vm_mm = mm; + retval = dup_userfaultfd(tmp, &uf); + if (retval) + goto fail_nomem_anon_vma_fork; + if (tmp->vm_flags & VM_WIPEONFORK) { + /* VM_WIPEONFORK gets a clean slate in the child. */ + tmp->anon_vma = NULL; + if (anon_vma_prepare(tmp)) + goto fail_nomem_anon_vma_fork; + } else if (anon_vma_fork(tmp, mpnt)) + goto fail_nomem_anon_vma_fork; + tmp->vm_flags &= ~(VM_LOCKED | VM_LOCKONFAULT); + tmp->vm_next = tmp->vm_prev = NULL; + file = tmp->vm_file; + if (file) { + struct inode *inode = file_inode(file); + struct address_space *mapping = file->f_mapping; + + get_file(file); + if (tmp->vm_flags & VM_DENYWRITE) + atomic_dec(&inode->i_writecount); + i_mmap_lock_write(mapping); + if (tmp->vm_flags & VM_SHARED) + atomic_inc(&mapping->i_mmap_writable); + flush_dcache_mmap_lock(mapping); + /* insert tmp into the share list, just after mpnt */ + vma_interval_tree_insert_after(tmp, mpnt, + &mapping->i_mmap); + flush_dcache_mmap_unlock(mapping); + i_mmap_unlock_write(mapping); + } + + /* + * Clear hugetlb-related page reserves for children. This only + * affects MAP_PRIVATE mappings. Faults generated by the child + * are not guaranteed to succeed, even if read-only + */ + if (is_vm_hugetlb_page(tmp)) + reset_vma_resv_huge_pages(tmp); + + /* + * Link in the new vma and copy the page table entries. + */ + *pprev = tmp; + pprev = &tmp->vm_next; + tmp->vm_prev = prev; + prev = tmp; + + __vma_link_rb(mm, tmp, rb_link, rb_parent); + rb_link = &tmp->vm_rb.rb_right; + rb_parent = &tmp->vm_rb; + + mm->map_count++; + if (!(tmp->vm_flags & VM_WIPEONFORK)) + retval = copy_page_range(mm, oldmm, mpnt); + + if (tmp->vm_ops && tmp->vm_ops->open) + tmp->vm_ops->open(tmp); + + if (retval) + goto out; + } + /* a new mm has just been created */ + arch_dup_mmap(oldmm, mm); + retval = 0; +out: + up_write(&mm->mmap_sem); + flush_tlb_mm(oldmm); + up_write(&oldmm->mmap_sem); + dup_userfaultfd_complete(&uf); +fail_uprobe_end: + uprobe_end_dup_mmap(); + return retval; +fail_nomem_anon_vma_fork: + mpol_put(vma_policy(tmp)); +fail_nomem_policy: + kmem_cache_free(vm_area_cachep, tmp); +fail_nomem: + retval = -ENOMEM; + vm_unacct_memory(charge); + goto out; +} + +static inline int mm_alloc_pgd(struct mm_struct *mm) +{ + mm->pgd = pgd_alloc(mm); + if (unlikely(!mm->pgd)) + return -ENOMEM; + return 0; +} + +static inline void mm_free_pgd(struct mm_struct *mm) +{ + pgd_free(mm, mm->pgd); +} +#else +static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) +{ + down_write(&oldmm->mmap_sem); + RCU_INIT_POINTER(mm->exe_file, get_mm_exe_file(oldmm)); + up_write(&oldmm->mmap_sem); + return 0; +} +#define mm_alloc_pgd(mm) (0) +#define mm_free_pgd(mm) +#endif /* CONFIG_MMU */ + +static void check_mm(struct mm_struct *mm) +{ + int i; + + for (i = 0; i < NR_MM_COUNTERS; i++) { + long x = atomic_long_read(&mm->rss_stat.count[i]); + + if (unlikely(x)) + printk(KERN_ALERT "BUG: Bad rss-counter state " + "mm:%p idx:%d val:%ld\n", mm, i, x); + } + + if (mm_pgtables_bytes(mm)) + pr_alert("BUG: non-zero pgtables_bytes on freeing mm: %ld\n", + mm_pgtables_bytes(mm)); + +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS + VM_BUG_ON_MM(mm->pmd_huge_pte, mm); +#endif +} + +#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL)) +#define free_mm(mm) (kmem_cache_free(mm_cachep, (mm))) + +/* + * Called when the last reference to the mm + * is dropped: either by a lazy thread or by + * mmput. Free the page directory and the mm. + */ +static void __mmdrop(struct mm_struct *mm) +{ + BUG_ON(mm == &init_mm); + mm_free_pgd(mm); + destroy_context(mm); + hmm_mm_destroy(mm); + mmu_notifier_mm_destroy(mm); + check_mm(mm); + put_user_ns(mm->user_ns); + free_mm(mm); +} + +void mmdrop(struct mm_struct *mm) +{ + /* + * The implicit full barrier implied by atomic_dec_and_test() is + * required by the membarrier system call before returning to + * user-space, after storing to rq->curr. + */ + if (unlikely(atomic_dec_and_test(&mm->mm_count))) + __mmdrop(mm); +} +EXPORT_SYMBOL_GPL(mmdrop); + +static void mmdrop_async_fn(struct work_struct *work) +{ + struct mm_struct *mm; + + mm = container_of(work, struct mm_struct, async_put_work); + __mmdrop(mm); +} + +static void mmdrop_async(struct mm_struct *mm) +{ + if (unlikely(atomic_dec_and_test(&mm->mm_count))) { + INIT_WORK(&mm->async_put_work, mmdrop_async_fn); + schedule_work(&mm->async_put_work); + } +} + static inline void free_signal_struct(struct signal_struct *sig) { taskstats_tgid_free(sig); @@ -457,6 +699,21 @@ static void set_max_threads(unsigned int max_threads_suggested) int arch_task_struct_size __read_mostly; #endif +static void task_struct_whitelist(unsigned long *offset, unsigned long *size) +{ + /* Fetch thread_struct whitelist for the architecture. */ + arch_thread_struct_whitelist(offset, size); + + /* + * Handle zero-sized whitelist or empty thread_struct, otherwise + * adjust offset to position of thread_struct in task_struct. + */ + if (unlikely(*size == 0)) + *offset = 0; + else + *offset += offsetof(struct task_struct, thread); +} + void __init fork_init(void) { int i; @@ -465,11 +722,14 @@ void __init fork_init(void) #define ARCH_MIN_TASKALIGN 0 #endif int align = max_t(int, L1_CACHE_BYTES, ARCH_MIN_TASKALIGN); + unsigned long useroffset, usersize; /* create a slab on which task_structs can be allocated */ - task_struct_cachep = kmem_cache_create("task_struct", + task_struct_whitelist(&useroffset, &usersize); + task_struct_cachep = kmem_cache_create_usercopy("task_struct", arch_task_struct_size, align, - SLAB_PANIC|SLAB_ACCOUNT, NULL); + SLAB_PANIC|SLAB_ACCOUNT, + useroffset, usersize, NULL); #endif /* do the arch specific task caches init */ @@ -594,181 +854,8 @@ free_tsk: return NULL; } -#ifdef CONFIG_MMU -static __latent_entropy int dup_mmap(struct mm_struct *mm, - struct mm_struct *oldmm) -{ - struct vm_area_struct *mpnt, *tmp, *prev, **pprev; - struct rb_node **rb_link, *rb_parent; - int retval; - unsigned long charge; - LIST_HEAD(uf); - - uprobe_start_dup_mmap(); - if (down_write_killable(&oldmm->mmap_sem)) { - retval = -EINTR; - goto fail_uprobe_end; - } - flush_cache_dup_mm(oldmm); - uprobe_dup_mmap(oldmm, mm); - /* - * Not linked in yet - no deadlock potential: - */ - down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING); - - /* No ordering required: file already has been exposed. */ - RCU_INIT_POINTER(mm->exe_file, get_mm_exe_file(oldmm)); - - mm->total_vm = oldmm->total_vm; - mm->data_vm = oldmm->data_vm; - mm->exec_vm = oldmm->exec_vm; - mm->stack_vm = oldmm->stack_vm; - - rb_link = &mm->mm_rb.rb_node; - rb_parent = NULL; - pprev = &mm->mmap; - retval = ksm_fork(mm, oldmm); - if (retval) - goto out; - retval = khugepaged_fork(mm, oldmm); - if (retval) - goto out; - - prev = NULL; - for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { - struct file *file; - - if (mpnt->vm_flags & VM_DONTCOPY) { - vm_stat_account(mm, mpnt->vm_flags, -vma_pages(mpnt)); - continue; - } - charge = 0; - if (mpnt->vm_flags & VM_ACCOUNT) { - unsigned long len = vma_pages(mpnt); - - if (security_vm_enough_memory_mm(oldmm, len)) /* sic */ - goto fail_nomem; - charge = len; - } - tmp = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); - if (!tmp) - goto fail_nomem; - *tmp = *mpnt; - INIT_LIST_HEAD(&tmp->anon_vma_chain); - retval = vma_dup_policy(mpnt, tmp); - if (retval) - goto fail_nomem_policy; - tmp->vm_mm = mm; - retval = dup_userfaultfd(tmp, &uf); - if (retval) - goto fail_nomem_anon_vma_fork; - if (tmp->vm_flags & VM_WIPEONFORK) { - /* VM_WIPEONFORK gets a clean slate in the child. */ - tmp->anon_vma = NULL; - if (anon_vma_prepare(tmp)) - goto fail_nomem_anon_vma_fork; - } else if (anon_vma_fork(tmp, mpnt)) - goto fail_nomem_anon_vma_fork; - tmp->vm_flags &= ~(VM_LOCKED | VM_LOCKONFAULT); - tmp->vm_next = tmp->vm_prev = NULL; - file = tmp->vm_file; - if (file) { - struct inode *inode = file_inode(file); - struct address_space *mapping = file->f_mapping; - - get_file(file); - if (tmp->vm_flags & VM_DENYWRITE) - atomic_dec(&inode->i_writecount); - i_mmap_lock_write(mapping); - if (tmp->vm_flags & VM_SHARED) - atomic_inc(&mapping->i_mmap_writable); - flush_dcache_mmap_lock(mapping); - /* insert tmp into the share list, just after mpnt */ - vma_interval_tree_insert_after(tmp, mpnt, - &mapping->i_mmap); - flush_dcache_mmap_unlock(mapping); - i_mmap_unlock_write(mapping); - } - - /* - * Clear hugetlb-related page reserves for children. This only - * affects MAP_PRIVATE mappings. Faults generated by the child - * are not guaranteed to succeed, even if read-only - */ - if (is_vm_hugetlb_page(tmp)) - reset_vma_resv_huge_pages(tmp); - - /* - * Link in the new vma and copy the page table entries. - */ - *pprev = tmp; - pprev = &tmp->vm_next; - tmp->vm_prev = prev; - prev = tmp; - - __vma_link_rb(mm, tmp, rb_link, rb_parent); - rb_link = &tmp->vm_rb.rb_right; - rb_parent = &tmp->vm_rb; - - mm->map_count++; - if (!(tmp->vm_flags & VM_WIPEONFORK)) - retval = copy_page_range(mm, oldmm, mpnt); - - if (tmp->vm_ops && tmp->vm_ops->open) - tmp->vm_ops->open(tmp); - - if (retval) - goto out; - } - /* a new mm has just been created */ - retval = arch_dup_mmap(oldmm, mm); -out: - up_write(&mm->mmap_sem); - flush_tlb_mm(oldmm); - up_write(&oldmm->mmap_sem); - dup_userfaultfd_complete(&uf); -fail_uprobe_end: - uprobe_end_dup_mmap(); - return retval; -fail_nomem_anon_vma_fork: - mpol_put(vma_policy(tmp)); -fail_nomem_policy: - kmem_cache_free(vm_area_cachep, tmp); -fail_nomem: - retval = -ENOMEM; - vm_unacct_memory(charge); - goto out; -} - -static inline int mm_alloc_pgd(struct mm_struct *mm) -{ - mm->pgd = pgd_alloc(mm); - if (unlikely(!mm->pgd)) - return -ENOMEM; - return 0; -} - -static inline void mm_free_pgd(struct mm_struct *mm) -{ - pgd_free(mm, mm->pgd); -} -#else -static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) -{ - down_write(&oldmm->mmap_sem); - RCU_INIT_POINTER(mm->exe_file, get_mm_exe_file(oldmm)); - up_write(&oldmm->mmap_sem); - return 0; -} -#define mm_alloc_pgd(mm) (0) -#define mm_free_pgd(mm) -#endif /* CONFIG_MMU */ - __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock); -#define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL)) -#define free_mm(mm) (kmem_cache_free(mm_cachep, (mm))) - static unsigned long default_dump_filter = MMF_DUMP_FILTER_DEFAULT; static int __init coredump_filter_setup(char *s) @@ -858,27 +945,6 @@ fail_nopgd: return NULL; } -static void check_mm(struct mm_struct *mm) -{ - int i; - - for (i = 0; i < NR_MM_COUNTERS; i++) { - long x = atomic_long_read(&mm->rss_stat.count[i]); - - if (unlikely(x)) - printk(KERN_ALERT "BUG: Bad rss-counter state " - "mm:%p idx:%d val:%ld\n", mm, i, x); - } - - if (mm_pgtables_bytes(mm)) - pr_alert("BUG: non-zero pgtables_bytes on freeing mm: %ld\n", - mm_pgtables_bytes(mm)); - -#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS - VM_BUG_ON_MM(mm->pmd_huge_pte, mm); -#endif -} - /* * Allocate and initialize an mm_struct. */ @@ -894,24 +960,6 @@ struct mm_struct *mm_alloc(void) return mm_init(mm, current, current_user_ns()); } -/* - * Called when the last reference to the mm - * is dropped: either by a lazy thread or by - * mmput. Free the page directory and the mm. - */ -void __mmdrop(struct mm_struct *mm) -{ - BUG_ON(mm == &init_mm); - mm_free_pgd(mm); - destroy_context(mm); - hmm_mm_destroy(mm); - mmu_notifier_mm_destroy(mm); - check_mm(mm); - put_user_ns(mm->user_ns); - free_mm(mm); -} -EXPORT_SYMBOL_GPL(__mmdrop); - static inline void __mmput(struct mm_struct *mm) { VM_BUG_ON(atomic_read(&mm->mm_users)); @@ -2224,9 +2272,11 @@ void __init proc_caches_init(void) * maximum number of CPU's we can ever have. The cpumask_allocation * is at the end of the structure, exactly for that reason. */ - mm_cachep = kmem_cache_create("mm_struct", + mm_cachep = kmem_cache_create_usercopy("mm_struct", sizeof(struct mm_struct), ARCH_MIN_MMSTRUCT_ALIGN, SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT, + offsetof(struct mm_struct, saved_auxv), + sizeof_field(struct mm_struct, saved_auxv), NULL); vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT); mmap_init(); diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c index 4e8089b..8c82ea2 100644 --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -71,7 +71,7 @@ unsigned long probe_irq_on(void) raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; - if (irq_startup(desc, IRQ_NORESEND, IRQ_START_FORCE)) + if (irq_activate_and_startup(desc, IRQ_NORESEND)) desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 043bfc3..c69357a 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -294,11 +294,11 @@ int irq_activate(struct irq_desc *desc) return 0; } -void irq_activate_and_startup(struct irq_desc *desc, bool resend) +int irq_activate_and_startup(struct irq_desc *desc, bool resend) { if (WARN_ON(irq_activate(desc))) - return; - irq_startup(desc, resend, IRQ_START_FORCE); + return 0; + return irq_startup(desc, resend, IRQ_START_FORCE); } static void __irq_disable(struct irq_desc *desc, bool mask); diff --git a/kernel/irq/debug.h b/kernel/irq/debug.h index e4d3819..8ccb326 100644 --- a/kernel/irq/debug.h +++ b/kernel/irq/debug.h @@ -3,8 +3,6 @@ * Debugging printout: */ -#include <linux/kallsyms.h> - #define ___P(f) if (desc->status_use_accessors & f) printk("%14s set\n", #f) #define ___PS(f) if (desc->istate & f) printk("%14s set\n", #f) /* FIXME */ @@ -19,14 +17,14 @@ static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc) printk("irq %d, desc: %p, depth: %d, count: %d, unhandled: %d\n", irq, desc, desc->depth, desc->irq_count, desc->irqs_unhandled); - printk("->handle_irq(): %p, ", desc->handle_irq); - print_symbol("%s\n", (unsigned long)desc->handle_irq); - printk("->irq_data.chip(): %p, ", desc->irq_data.chip); - print_symbol("%s\n", (unsigned long)desc->irq_data.chip); + printk("->handle_irq(): %p, %pS\n", + desc->handle_irq, desc->handle_irq); + printk("->irq_data.chip(): %p, %pS\n", + desc->irq_data.chip, desc->irq_data.chip); printk("->action(): %p\n", desc->action); if (desc->action) { - printk("->action->handler(): %p, ", desc->action->handler); - print_symbol("%s\n", (unsigned long)desc->action->handler); + printk("->action->handler(): %p, %pS\n", + desc->action->handler, desc->action->handler); } ___P(IRQ_LEVEL); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index ab19371..ca6afa2 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -76,7 +76,7 @@ extern void __enable_irq(struct irq_desc *desc); #define IRQ_START_COND false extern int irq_activate(struct irq_desc *desc); -extern void irq_activate_and_startup(struct irq_desc *desc, bool resend); +extern int irq_activate_and_startup(struct irq_desc *desc, bool resend); extern int irq_startup(struct irq_desc *desc, bool resend, bool force); extern void irq_shutdown(struct irq_desc *desc); diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index d5fa411..a23e21a 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -12,7 +12,6 @@ * compression (see scripts/kallsyms.c for a more complete description) */ #include <linux/kallsyms.h> -#include <linux/module.h> #include <linux/init.h> #include <linux/seq_file.h> #include <linux/fs.h> @@ -20,15 +19,12 @@ #include <linux/err.h> #include <linux/proc_fs.h> #include <linux/sched.h> /* for cond_resched */ -#include <linux/mm.h> #include <linux/ctype.h> #include <linux/slab.h> #include <linux/filter.h> #include <linux/ftrace.h> #include <linux/compiler.h> -#include <asm/sections.h> - /* * These will be re-linked against their real values * during the second link stage. @@ -52,37 +48,6 @@ extern const u16 kallsyms_token_index[] __weak; extern const unsigned long kallsyms_markers[] __weak; -static inline int is_kernel_inittext(unsigned long addr) -{ - if (addr >= (unsigned long)_sinittext - && addr <= (unsigned long)_einittext) - return 1; - return 0; -} - -static inline int is_kernel_text(unsigned long addr) -{ - if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) || - arch_is_kernel_text(addr)) - return 1; - return in_gate_area_no_mm(addr); -} - -static inline int is_kernel(unsigned long addr) -{ - if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end) - return 1; - return in_gate_area_no_mm(addr); -} - -static int is_ksym_addr(unsigned long addr) -{ - if (IS_ENABLED(CONFIG_KALLSYMS_ALL)) - return is_kernel(addr); - - return is_kernel_text(addr) || is_kernel_inittext(addr); -} - /* * Expand a compressed symbol data into the resulting uncompressed string, * if uncompressed string is too long (>= maxlen), it will be truncated, @@ -464,17 +429,6 @@ int sprint_backtrace(char *buffer, unsigned long address) return __sprint_symbol(buffer, address, -1, 1); } -/* Look up a kernel symbol and print it to the kernel messages. */ -void __print_symbol(const char *fmt, unsigned long address) -{ - char buffer[KSYM_SYMBOL_LEN]; - - sprint_symbol(buffer, address); - - printk(fmt, buffer); -} -EXPORT_SYMBOL(__print_symbol); - /* To avoid using get_symbol_offset for every symbol, we carry prefix along. */ struct kallsym_iter { loff_t pos; diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index de9e45d..3a4656f 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -366,11 +366,6 @@ static int __klp_enable_patch(struct klp_patch *patch) /* * A reference is taken on the patch module to prevent it from being * unloaded. - * - * Note: For immediate (no consistency model) patches we don't allow - * patch modules to unload since there is no safe/sane method to - * determine if a thread is still running in the patched code contained - * in the patch module once the ftrace registration is successful. */ if (!try_module_get(patch->mod)) return -ENODEV; @@ -454,6 +449,8 @@ EXPORT_SYMBOL_GPL(klp_enable_patch); * /sys/kernel/livepatch/<patch> * /sys/kernel/livepatch/<patch>/enabled * /sys/kernel/livepatch/<patch>/transition + * /sys/kernel/livepatch/<patch>/signal + * /sys/kernel/livepatch/<patch>/force * /sys/kernel/livepatch/<patch>/<object> * /sys/kernel/livepatch/<patch>/<object>/<function,sympos> */ @@ -528,11 +525,73 @@ static ssize_t transition_show(struct kobject *kobj, patch == klp_transition_patch); } +static ssize_t signal_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct klp_patch *patch; + int ret; + bool val; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + if (!val) + return count; + + mutex_lock(&klp_mutex); + + patch = container_of(kobj, struct klp_patch, kobj); + if (patch != klp_transition_patch) { + mutex_unlock(&klp_mutex); + return -EINVAL; + } + + klp_send_signals(); + + mutex_unlock(&klp_mutex); + + return count; +} + +static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct klp_patch *patch; + int ret; + bool val; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + if (!val) + return count; + + mutex_lock(&klp_mutex); + + patch = container_of(kobj, struct klp_patch, kobj); + if (patch != klp_transition_patch) { + mutex_unlock(&klp_mutex); + return -EINVAL; + } + + klp_force_transition(); + + mutex_unlock(&klp_mutex); + + return count; +} + static struct kobj_attribute enabled_kobj_attr = __ATTR_RW(enabled); static struct kobj_attribute transition_kobj_attr = __ATTR_RO(transition); +static struct kobj_attribute signal_kobj_attr = __ATTR_WO(signal); +static struct kobj_attribute force_kobj_attr = __ATTR_WO(force); static struct attribute *klp_patch_attrs[] = { &enabled_kobj_attr.attr, &transition_kobj_attr.attr, + &signal_kobj_attr.attr, + &force_kobj_attr.attr, NULL }; @@ -830,12 +889,7 @@ int klp_register_patch(struct klp_patch *patch) if (!klp_initialized()) return -ENODEV; - /* - * Architectures without reliable stack traces have to set - * patch->immediate because there's currently no way to patch kthreads - * with the consistency model. - */ - if (!klp_have_reliable_stack() && !patch->immediate) { + if (!klp_have_reliable_stack()) { pr_err("This architecture doesn't have support for the livepatch consistency model.\n"); return -ENOSYS; } diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index 56add63..7c6631e 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -33,6 +33,8 @@ struct klp_patch *klp_transition_patch; static int klp_target_state = KLP_UNDEFINED; +static bool klp_forced = false; + /* * This work can be performed periodically to finish patching or unpatching any * "straggler" tasks which failed to transition in the first attempt. @@ -80,7 +82,6 @@ static void klp_complete_transition(void) struct klp_func *func; struct task_struct *g, *task; unsigned int cpu; - bool immediate_func = false; pr_debug("'%s': completing %s transition\n", klp_transition_patch->mod->name, @@ -102,16 +103,9 @@ static void klp_complete_transition(void) klp_synchronize_transition(); } - if (klp_transition_patch->immediate) - goto done; - - klp_for_each_object(klp_transition_patch, obj) { - klp_for_each_func(obj, func) { + klp_for_each_object(klp_transition_patch, obj) + klp_for_each_func(obj, func) func->transition = false; - if (func->immediate) - immediate_func = true; - } - } /* Prevent klp_ftrace_handler() from seeing KLP_UNDEFINED state */ if (klp_target_state == KLP_PATCHED) @@ -130,7 +124,6 @@ static void klp_complete_transition(void) task->patch_state = KLP_UNDEFINED; } -done: klp_for_each_object(klp_transition_patch, obj) { if (!klp_is_object_loaded(obj)) continue; @@ -144,13 +137,11 @@ done: klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * See complementary comment in __klp_enable_patch() for why we - * keep the module reference for immediate patches. + * klp_forced set implies unbounded increase of module's ref count if + * the module is disabled/enabled in a loop. */ - if (!klp_transition_patch->immediate && !immediate_func && - klp_target_state == KLP_UNPATCHED) { + if (!klp_forced && klp_target_state == KLP_UNPATCHED) module_put(klp_transition_patch->mod); - } klp_target_state = KLP_UNDEFINED; klp_transition_patch = NULL; @@ -218,9 +209,6 @@ static int klp_check_stack_func(struct klp_func *func, struct klp_ops *ops; int i; - if (func->immediate) - return 0; - for (i = 0; i < trace->nr_entries; i++) { address = trace->entries[i]; @@ -383,13 +371,6 @@ void klp_try_complete_transition(void) WARN_ON_ONCE(klp_target_state == KLP_UNDEFINED); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (klp_transition_patch->immediate) - goto success; - - /* * Try to switch the tasks to the target patch state by walking their * stacks and looking for any to-be-patched or to-be-unpatched * functions. If such functions are found on a stack, or if the stack @@ -432,7 +413,6 @@ void klp_try_complete_transition(void) return; } -success: /* we're done, now cleanup the data structures */ klp_complete_transition(); } @@ -453,13 +433,6 @@ void klp_start_transition(void) klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (klp_transition_patch->immediate) - return; - - /* * Mark all normal tasks as needing a patch state update. They'll * switch either in klp_try_complete_transition() or as they exit the * kernel. @@ -509,13 +482,6 @@ void klp_init_transition(struct klp_patch *patch, int state) klp_target_state == KLP_PATCHED ? "patching" : "unpatching"); /* - * If the patch can be applied or reverted immediately, skip the - * per-task transitions. - */ - if (patch->immediate) - return; - - /* * Initialize all tasks to the initial patch state to prepare them for * switching to the target state. */ @@ -608,3 +574,71 @@ void klp_copy_process(struct task_struct *child) /* TIF_PATCH_PENDING gets copied in setup_thread_stack() */ } + +/* + * Sends a fake signal to all non-kthread tasks with TIF_PATCH_PENDING set. + * Kthreads with TIF_PATCH_PENDING set are woken up. Only admin can request this + * action currently. + */ +void klp_send_signals(void) +{ + struct task_struct *g, *task; + + pr_notice("signaling remaining tasks\n"); + + read_lock(&tasklist_lock); + for_each_process_thread(g, task) { + if (!klp_patch_pending(task)) + continue; + + /* + * There is a small race here. We could see TIF_PATCH_PENDING + * set and decide to wake up a kthread or send a fake signal. + * Meanwhile the task could migrate itself and the action + * would be meaningless. It is not serious though. + */ + if (task->flags & PF_KTHREAD) { + /* + * Wake up a kthread which sleeps interruptedly and + * still has not been migrated. + */ + wake_up_state(task, TASK_INTERRUPTIBLE); + } else { + /* + * Send fake signal to all non-kthread tasks which are + * still not migrated. + */ + spin_lock_irq(&task->sighand->siglock); + signal_wake_up(task, 0); + spin_unlock_irq(&task->sighand->siglock); + } + } + read_unlock(&tasklist_lock); +} + +/* + * Drop TIF_PATCH_PENDING of all tasks on admin's request. This forces an + * existing transition to finish. + * + * NOTE: klp_update_patch_state(task) requires the task to be inactive or + * 'current'. This is not the case here and the consistency model could be + * broken. Administrator, who is the only one to execute the + * klp_force_transitions(), has to be aware of this. + */ +void klp_force_transition(void) +{ + struct task_struct *g, *task; + unsigned int cpu; + + pr_warn("forcing remaining tasks to the patched state\n"); + + read_lock(&tasklist_lock); + for_each_process_thread(g, task) + klp_update_patch_state(task); + read_unlock(&tasklist_lock); + + for_each_possible_cpu(cpu) + klp_update_patch_state(idle_task(cpu)); + + klp_forced = true; +} diff --git a/kernel/livepatch/transition.h b/kernel/livepatch/transition.h index 0f6e27c..f9d0bc0 100644 --- a/kernel/livepatch/transition.h +++ b/kernel/livepatch/transition.h @@ -11,5 +11,7 @@ void klp_cancel_transition(void); void klp_start_transition(void); void klp_try_complete_transition(void); void klp_reverse_transition(void); +void klp_send_signals(void); +void klp_force_transition(void); #endif /* _LIVEPATCH_TRANSITION_H */ diff --git a/kernel/memremap.c b/kernel/memremap.c index 403ab9c..4849be5 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -188,13 +188,6 @@ static RADIX_TREE(pgmap_radix, GFP_KERNEL); #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1) #define SECTION_SIZE (1UL << PA_SECTION_SHIFT) -struct page_map { - struct resource res; - struct percpu_ref *ref; - struct dev_pagemap pgmap; - struct vmem_altmap altmap; -}; - static unsigned long order_at(struct resource *res, unsigned long pgoff) { unsigned long phys_pgoff = PHYS_PFN(res->start) + pgoff; @@ -248,34 +241,36 @@ int device_private_entry_fault(struct vm_area_struct *vma, EXPORT_SYMBOL(device_private_entry_fault); #endif /* CONFIG_DEVICE_PRIVATE */ -static void pgmap_radix_release(struct resource *res) +static void pgmap_radix_release(struct resource *res, unsigned long end_pgoff) { unsigned long pgoff, order; mutex_lock(&pgmap_lock); - foreach_order_pgoff(res, order, pgoff) + foreach_order_pgoff(res, order, pgoff) { + if (pgoff >= end_pgoff) + break; radix_tree_delete(&pgmap_radix, PHYS_PFN(res->start) + pgoff); + } mutex_unlock(&pgmap_lock); synchronize_rcu(); } -static unsigned long pfn_first(struct page_map *page_map) +static unsigned long pfn_first(struct dev_pagemap *pgmap) { - struct dev_pagemap *pgmap = &page_map->pgmap; - const struct resource *res = &page_map->res; - struct vmem_altmap *altmap = pgmap->altmap; + const struct resource *res = &pgmap->res; + struct vmem_altmap *altmap = &pgmap->altmap; unsigned long pfn; pfn = res->start >> PAGE_SHIFT; - if (altmap) + if (pgmap->altmap_valid) pfn += vmem_altmap_offset(altmap); return pfn; } -static unsigned long pfn_end(struct page_map *page_map) +static unsigned long pfn_end(struct dev_pagemap *pgmap) { - const struct resource *res = &page_map->res; + const struct resource *res = &pgmap->res; return (res->start + resource_size(res)) >> PAGE_SHIFT; } @@ -283,15 +278,15 @@ static unsigned long pfn_end(struct page_map *page_map) #define for_each_device_pfn(pfn, map) \ for (pfn = pfn_first(map); pfn < pfn_end(map); pfn++) -static void devm_memremap_pages_release(struct device *dev, void *data) +static void devm_memremap_pages_release(void *data) { - struct page_map *page_map = data; - struct resource *res = &page_map->res; + struct dev_pagemap *pgmap = data; + struct device *dev = pgmap->dev; + struct resource *res = &pgmap->res; resource_size_t align_start, align_size; - struct dev_pagemap *pgmap = &page_map->pgmap; unsigned long pfn; - for_each_device_pfn(pfn, page_map) + for_each_device_pfn(pfn, pgmap) put_page(pfn_to_page(pfn)); if (percpu_ref_tryget_live(pgmap->ref)) { @@ -301,56 +296,51 @@ static void devm_memremap_pages_release(struct device *dev, void *data) /* pages are dead and unused, undo the arch mapping */ align_start = res->start & ~(SECTION_SIZE - 1); - align_size = ALIGN(resource_size(res), SECTION_SIZE); + align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE) + - align_start; mem_hotplug_begin(); - arch_remove_memory(align_start, align_size); + arch_remove_memory(align_start, align_size, pgmap->altmap_valid ? + &pgmap->altmap : NULL); mem_hotplug_done(); untrack_pfn(NULL, PHYS_PFN(align_start), align_size); - pgmap_radix_release(res); - dev_WARN_ONCE(dev, pgmap->altmap && pgmap->altmap->alloc, - "%s: failed to free all reserved pages\n", __func__); -} - -/* assumes rcu_read_lock() held at entry */ -struct dev_pagemap *find_dev_pagemap(resource_size_t phys) -{ - struct page_map *page_map; - - WARN_ON_ONCE(!rcu_read_lock_held()); - - page_map = radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys)); - return page_map ? &page_map->pgmap : NULL; + pgmap_radix_release(res, -1); + dev_WARN_ONCE(dev, pgmap->altmap.alloc, + "%s: failed to free all reserved pages\n", __func__); } /** * devm_memremap_pages - remap and provide memmap backing for the given resource * @dev: hosting device for @res - * @res: "host memory" address range - * @ref: a live per-cpu reference count - * @altmap: optional descriptor for allocating the memmap from @res + * @pgmap: pointer to a struct dev_pgmap * * Notes: - * 1/ @ref must be 'live' on entry and 'dead' before devm_memunmap_pages() time - * (or devm release event). The expected order of events is that @ref has + * 1/ At a minimum the res, ref and type members of @pgmap must be initialized + * by the caller before passing it to this function + * + * 2/ The altmap field may optionally be initialized, in which case altmap_valid + * must be set to true + * + * 3/ pgmap.ref must be 'live' on entry and 'dead' before devm_memunmap_pages() + * time (or devm release event). The expected order of events is that ref has * been through percpu_ref_kill() before devm_memremap_pages_release(). The * wait for the completion of all references being dropped and * percpu_ref_exit() must occur after devm_memremap_pages_release(). * - * 2/ @res is expected to be a host memory range that could feasibly be + * 4/ res is expected to be a host memory range that could feasibly be * treated as a "System RAM" range, i.e. not a device mmio range, but * this is not enforced. */ -void *devm_memremap_pages(struct device *dev, struct resource *res, - struct percpu_ref *ref, struct vmem_altmap *altmap) +void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) { resource_size_t align_start, align_size, align_end; + struct vmem_altmap *altmap = pgmap->altmap_valid ? + &pgmap->altmap : NULL; unsigned long pfn, pgoff, order; pgprot_t pgprot = PAGE_KERNEL; - struct dev_pagemap *pgmap; - struct page_map *page_map; int error, nid, is_ram, i = 0; + struct resource *res = &pgmap->res; align_start = res->start & ~(SECTION_SIZE - 1); align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE) @@ -367,47 +357,18 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, if (is_ram == REGION_INTERSECTS) return __va(res->start); - if (!ref) + if (!pgmap->ref) return ERR_PTR(-EINVAL); - page_map = devres_alloc_node(devm_memremap_pages_release, - sizeof(*page_map), GFP_KERNEL, dev_to_node(dev)); - if (!page_map) - return ERR_PTR(-ENOMEM); - pgmap = &page_map->pgmap; - - memcpy(&page_map->res, res, sizeof(*res)); - pgmap->dev = dev; - if (altmap) { - memcpy(&page_map->altmap, altmap, sizeof(*altmap)); - pgmap->altmap = &page_map->altmap; - } - pgmap->ref = ref; - pgmap->res = &page_map->res; - pgmap->type = MEMORY_DEVICE_HOST; - pgmap->page_fault = NULL; - pgmap->page_free = NULL; - pgmap->data = NULL; mutex_lock(&pgmap_lock); error = 0; align_end = align_start + align_size - 1; foreach_order_pgoff(res, order, pgoff) { - struct dev_pagemap *dup; - - rcu_read_lock(); - dup = find_dev_pagemap(res->start + PFN_PHYS(pgoff)); - rcu_read_unlock(); - if (dup) { - dev_err(dev, "%s: %pr collides with mapping for %s\n", - __func__, res, dev_name(dup->dev)); - error = -EBUSY; - break; - } error = __radix_tree_insert(&pgmap_radix, - PHYS_PFN(res->start) + pgoff, order, page_map); + PHYS_PFN(res->start) + pgoff, order, pgmap); if (error) { dev_err(dev, "%s: failed: %d\n", __func__, error); break; @@ -427,16 +388,16 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, goto err_pfn_remap; mem_hotplug_begin(); - error = arch_add_memory(nid, align_start, align_size, false); + error = arch_add_memory(nid, align_start, align_size, altmap, false); if (!error) move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT); + align_size >> PAGE_SHIFT, altmap); mem_hotplug_done(); if (error) goto err_add_memory; - for_each_device_pfn(pfn, page_map) { + for_each_device_pfn(pfn, pgmap) { struct page *page = pfn_to_page(pfn); /* @@ -447,19 +408,21 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, */ list_del(&page->lru); page->pgmap = pgmap; - percpu_ref_get(ref); + percpu_ref_get(pgmap->ref); if (!(++i % 1024)) cond_resched(); } - devres_add(dev, page_map); + + devm_add_action(dev, devm_memremap_pages_release, pgmap); + return __va(res->start); err_add_memory: untrack_pfn(NULL, PHYS_PFN(align_start), align_size); err_pfn_remap: err_radix: - pgmap_radix_release(res); - devres_free(page_map); + pgmap_radix_release(res, pgoff); + devres_free(pgmap); return ERR_PTR(error); } EXPORT_SYMBOL(devm_memremap_pages); @@ -475,34 +438,39 @@ void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns) altmap->alloc -= nr_pfns; } -struct vmem_altmap *to_vmem_altmap(unsigned long memmap_start) +/** + * get_dev_pagemap() - take a new live reference on the dev_pagemap for @pfn + * @pfn: page frame number to lookup page_map + * @pgmap: optional known pgmap that already has a reference + * + * If @pgmap is non-NULL and covers @pfn it will be returned as-is. If @pgmap + * is non-NULL but does not cover @pfn the reference to it will be released. + */ +struct dev_pagemap *get_dev_pagemap(unsigned long pfn, + struct dev_pagemap *pgmap) { - /* - * 'memmap_start' is the virtual address for the first "struct - * page" in this range of the vmemmap array. In the case of - * CONFIG_SPARSEMEM_VMEMMAP a page_to_pfn conversion is simple - * pointer arithmetic, so we can perform this to_vmem_altmap() - * conversion without concern for the initialization state of - * the struct page fields. - */ - struct page *page = (struct page *) memmap_start; - struct dev_pagemap *pgmap; + resource_size_t phys = PFN_PHYS(pfn); /* - * Unconditionally retrieve a dev_pagemap associated with the - * given physical address, this is only for use in the - * arch_{add|remove}_memory() for setting up and tearing down - * the memmap. + * In the cached case we're already holding a live reference. */ + if (pgmap) { + if (phys >= pgmap->res.start && phys <= pgmap->res.end) + return pgmap; + put_dev_pagemap(pgmap); + } + + /* fall back to slow path lookup */ rcu_read_lock(); - pgmap = find_dev_pagemap(__pfn_to_phys(page_to_pfn(page))); + pgmap = radix_tree_lookup(&pgmap_radix, PHYS_PFN(phys)); + if (pgmap && !percpu_ref_tryget_live(pgmap->ref)) + pgmap = NULL; rcu_read_unlock(); - return pgmap ? pgmap->altmap : NULL; + return pgmap; } #endif /* CONFIG_ZONE_DEVICE */ - #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC) void put_zone_device_private_or_public_page(struct page *page) { diff --git a/kernel/module.c b/kernel/module.c index 09e48ee..ccdf24c 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3129,7 +3129,11 @@ static int find_module_sections(struct module *mod, struct load_info *info) sizeof(*mod->ftrace_callsites), &mod->num_ftrace_callsites); #endif - +#ifdef CONFIG_FUNCTION_ERROR_INJECTION + mod->ei_funcs = section_objs(info, "_error_injection_whitelist", + sizeof(*mod->ei_funcs), + &mod->num_ei_funcs); +#endif mod->extable = section_objs(info, "__ex_table", sizeof(*mod->extable), &mod->num_exentries); @@ -3949,6 +3953,12 @@ static const char *get_ksymbol(struct module *mod, return symname(kallsyms, best); } +void * __weak dereference_module_function_descriptor(struct module *mod, + void *ptr) +{ + return ptr; +} + /* For kallsyms to ask for address resolution. NULL means not found. Careful * not to lock to avoid deadlock on oopses, simply disable preemption. */ const char *module_address_lookup(unsigned long addr, diff --git a/kernel/padata.c b/kernel/padata.c index 57c0074..d568cc5 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * padata.c - generic interface to process data streams in parallel * diff --git a/kernel/power/power.h b/kernel/power/power.h index f29cd17..9e58bdc 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -104,9 +104,6 @@ extern int in_suspend; extern dev_t swsusp_resume_device; extern sector_t swsusp_resume_block; -extern asmlinkage int swsusp_arch_suspend(void); -extern asmlinkage int swsusp_arch_resume(void); - extern int create_basic_memory_bitmaps(void); extern void free_basic_memory_bitmaps(void); extern int hibernate_preallocate_memory(void); diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index b900661..db4b9b8 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -131,13 +131,10 @@ static int __init control_devkmsg(char *str) /* * Set sysctl string accordingly: */ - if (devkmsg_log == DEVKMSG_LOG_MASK_ON) { - memset(devkmsg_log_str, 0, DEVKMSG_STR_MAX_SIZE); - strncpy(devkmsg_log_str, "on", 2); - } else if (devkmsg_log == DEVKMSG_LOG_MASK_OFF) { - memset(devkmsg_log_str, 0, DEVKMSG_STR_MAX_SIZE); - strncpy(devkmsg_log_str, "off", 3); - } + if (devkmsg_log == DEVKMSG_LOG_MASK_ON) + strcpy(devkmsg_log_str, "on"); + else if (devkmsg_log == DEVKMSG_LOG_MASK_OFF) + strcpy(devkmsg_log_str, "off"); /* else "ratelimit" which is set by default. */ /* @@ -277,6 +274,13 @@ EXPORT_SYMBOL(console_set_on_cmdline); /* Flag: console code may call schedule() */ static int console_may_schedule; +enum con_msg_format_flags { + MSG_FORMAT_DEFAULT = 0, + MSG_FORMAT_SYSLOG = (1 << 0), +}; + +static int console_msg_format = MSG_FORMAT_DEFAULT; + /* * The printk log buffer consists of a chain of concatenated variable * length records. Every record starts with a record header, containing @@ -920,10 +924,10 @@ static loff_t devkmsg_llseek(struct file *file, loff_t offset, int whence) return ret; } -static unsigned int devkmsg_poll(struct file *file, poll_table *wait) +static __poll_t devkmsg_poll(struct file *file, poll_table *wait) { struct devkmsg_user *user = file->private_data; - int ret = 0; + __poll_t ret = 0; if (!user) return POLLERR|POLLNVAL; @@ -1544,6 +1548,146 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len) } /* + * Special console_lock variants that help to reduce the risk of soft-lockups. + * They allow to pass console_lock to another printk() call using a busy wait. + */ + +#ifdef CONFIG_LOCKDEP +static struct lockdep_map console_owner_dep_map = { + .name = "console_owner" +}; +#endif + +static DEFINE_RAW_SPINLOCK(console_owner_lock); +static struct task_struct *console_owner; +static bool console_waiter; + +/** + * console_lock_spinning_enable - mark beginning of code where another + * thread might safely busy wait + * + * This basically converts console_lock into a spinlock. This marks + * the section where the console_lock owner can not sleep, because + * there may be a waiter spinning (like a spinlock). Also it must be + * ready to hand over the lock at the end of the section. + */ +static void console_lock_spinning_enable(void) +{ + raw_spin_lock(&console_owner_lock); + console_owner = current; + raw_spin_unlock(&console_owner_lock); + + /* The waiter may spin on us after setting console_owner */ + spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_); +} + +/** + * console_lock_spinning_disable_and_check - mark end of code where another + * thread was able to busy wait and check if there is a waiter + * + * This is called at the end of the section where spinning is allowed. + * It has two functions. First, it is a signal that it is no longer + * safe to start busy waiting for the lock. Second, it checks if + * there is a busy waiter and passes the lock rights to her. + * + * Important: Callers lose the lock if there was a busy waiter. + * They must not touch items synchronized by console_lock + * in this case. + * + * Return: 1 if the lock rights were passed, 0 otherwise. + */ +static int console_lock_spinning_disable_and_check(void) +{ + int waiter; + + raw_spin_lock(&console_owner_lock); + waiter = READ_ONCE(console_waiter); + console_owner = NULL; + raw_spin_unlock(&console_owner_lock); + + if (!waiter) { + spin_release(&console_owner_dep_map, 1, _THIS_IP_); + return 0; + } + + /* The waiter is now free to continue */ + WRITE_ONCE(console_waiter, false); + + spin_release(&console_owner_dep_map, 1, _THIS_IP_); + + /* + * Hand off console_lock to waiter. The waiter will perform + * the up(). After this, the waiter is the console_lock owner. + */ + mutex_release(&console_lock_dep_map, 1, _THIS_IP_); + return 1; +} + +/** + * console_trylock_spinning - try to get console_lock by busy waiting + * + * This allows to busy wait for the console_lock when the current + * owner is running in specially marked sections. It means that + * the current owner is running and cannot reschedule until it + * is ready to lose the lock. + * + * Return: 1 if we got the lock, 0 othrewise + */ +static int console_trylock_spinning(void) +{ + struct task_struct *owner = NULL; + bool waiter; + bool spin = false; + unsigned long flags; + + if (console_trylock()) + return 1; + + printk_safe_enter_irqsave(flags); + + raw_spin_lock(&console_owner_lock); + owner = READ_ONCE(console_owner); + waiter = READ_ONCE(console_waiter); + if (!waiter && owner && owner != current) { + WRITE_ONCE(console_waiter, true); + spin = true; + } + raw_spin_unlock(&console_owner_lock); + + /* + * If there is an active printk() writing to the + * consoles, instead of having it write our data too, + * see if we can offload that load from the active + * printer, and do some printing ourselves. + * Go into a spin only if there isn't already a waiter + * spinning, and there is an active printer, and + * that active printer isn't us (recursive printk?). + */ + if (!spin) { + printk_safe_exit_irqrestore(flags); + return 0; + } + + /* We spin waiting for the owner to release us */ + spin_acquire(&console_owner_dep_map, 0, 0, _THIS_IP_); + /* Owner will clear console_waiter on hand off */ + while (READ_ONCE(console_waiter)) + cpu_relax(); + spin_release(&console_owner_dep_map, 1, _THIS_IP_); + + printk_safe_exit_irqrestore(flags); + /* + * The owner passed the console lock to us. + * Since we did not spin on console lock, annotate + * this as a trylock. Otherwise lockdep will + * complain. + */ + mutex_acquire(&console_lock_dep_map, 0, 1, _THIS_IP_); + + return 1; +} + +/* * Call the console drivers, asking them to write out * log_buf[start] to log_buf[end - 1]. * The console_lock must be held. @@ -1749,12 +1893,19 @@ asmlinkage int vprintk_emit(int facility, int level, /* If called from the scheduler, we can not call up(). */ if (!in_sched) { /* + * Disable preemption to avoid being preempted while holding + * console_sem which would prevent anyone from printing to + * console + */ + preempt_disable(); + /* * Try to acquire and then immediately release the console * semaphore. The release will print out buffers and wake up * /dev/kmsg and syslog() users. */ - if (console_trylock()) + if (console_trylock_spinning()) console_unlock(); + preempt_enable(); } return printed_len; @@ -1855,6 +2006,8 @@ static ssize_t msg_print_ext_header(char *buf, size_t size, static ssize_t msg_print_ext_body(char *buf, size_t size, char *dict, size_t dict_len, char *text, size_t text_len) { return 0; } +static void console_lock_spinning_enable(void) { } +static int console_lock_spinning_disable_and_check(void) { return 0; } static void call_console_drivers(const char *ext_text, size_t ext_len, const char *text, size_t len) {} static size_t msg_print_text(const struct printk_log *msg, @@ -1913,6 +2066,17 @@ static int __add_preferred_console(char *name, int idx, char *options, c->index = idx; return 0; } + +static int __init console_msg_format_setup(char *str) +{ + if (!strcmp(str, "syslog")) + console_msg_format = MSG_FORMAT_SYSLOG; + if (!strcmp(str, "default")) + console_msg_format = MSG_FORMAT_DEFAULT; + return 1; +} +__setup("console_msg_format=", console_msg_format_setup); + /* * Set up a console. Called via do_early_param() in init/main.c * for each "console=" parameter in the boot command line. @@ -2069,20 +2233,7 @@ int console_trylock(void) return 0; } console_locked = 1; - /* - * When PREEMPT_COUNT disabled we can't reliably detect if it's - * safe to schedule (e.g. calling printk while holding a spin_lock), - * because preempt_disable()/preempt_enable() are just barriers there - * and preempt_count() is always 0. - * - * RCU read sections have a separate preemption counter when - * PREEMPT_RCU enabled thus we must take extra care and check - * rcu_preempt_depth(), otherwise RCU read sections modify - * preempt_count(). - */ - console_may_schedule = !oops_in_progress && - preemptible() && - !rcu_preempt_depth(); + console_may_schedule = 0; return 1; } EXPORT_SYMBOL(console_trylock); @@ -2215,7 +2366,10 @@ skip: goto skip; } - len += msg_print_text(msg, false, text + len, sizeof(text) - len); + len += msg_print_text(msg, + console_msg_format & MSG_FORMAT_SYSLOG, + text + len, + sizeof(text) - len); if (nr_ext_console_drivers) { ext_len = msg_print_ext_header(ext_text, sizeof(ext_text), @@ -2229,14 +2383,29 @@ skip: console_seq++; raw_spin_unlock(&logbuf_lock); + /* + * While actively printing out messages, if another printk() + * were to occur on another CPU, it may wait for this one to + * finish. This task can not be preempted if there is a + * waiter waiting to take over. + */ + console_lock_spinning_enable(); + stop_critical_timings(); /* don't trace print latency */ call_console_drivers(ext_text, ext_len, text, len); start_critical_timings(); + + if (console_lock_spinning_disable_and_check()) { + printk_safe_exit_irqrestore(flags); + return; + } + printk_safe_exit_irqrestore(flags); if (do_cond_resched) cond_resched(); } + console_locked = 0; /* Release the exclusive_console once it is used */ diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 84b1367..5e1d713 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -659,7 +659,7 @@ static int ptrace_getsiginfo(struct task_struct *child, siginfo_t *info) if (lock_task_sighand(child, &flags)) { error = -EINVAL; if (likely(child->last_siginfo != NULL)) { - *info = *child->last_siginfo; + copy_siginfo(info, child->last_siginfo); error = 0; } unlock_task_sighand(child, &flags); @@ -675,7 +675,7 @@ static int ptrace_setsiginfo(struct task_struct *child, const siginfo_t *info) if (lock_task_sighand(child, &flags)) { error = -EINVAL; if (likely(child->last_siginfo != NULL)) { - *child->last_siginfo = *info; + copy_siginfo(child->last_siginfo, info); error = 0; } unlock_task_sighand(child, &flags); @@ -1092,6 +1092,10 @@ int ptrace_request(struct task_struct *child, long request, ret = seccomp_get_filter(child, addr, datavp); break; + case PTRACE_SECCOMP_GET_METADATA: + ret = seccomp_get_metadata(child, addr, datavp); + break; + default: break; } @@ -1226,7 +1230,6 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request, break; case PTRACE_SETSIGINFO: - memset(&siginfo, 0, sizeof siginfo); if (copy_siginfo_from_user32( &siginfo, (struct compat_siginfo __user *) datap)) ret = -EFAULT; diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index fbd56d6..68fa19a 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -422,11 +422,13 @@ void init_rcu_head(struct rcu_head *head) { debug_object_init(head, &rcuhead_debug_descr); } +EXPORT_SYMBOL_GPL(init_rcu_head); void destroy_rcu_head(struct rcu_head *head) { debug_object_free(head, &rcuhead_debug_descr); } +EXPORT_SYMBOL_GPL(destroy_rcu_head); static bool rcuhead_is_static_object(void *addr) { diff --git a/kernel/relay.c b/kernel/relay.c index 39a9dfc..4128003 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -919,9 +919,9 @@ static int relay_file_mmap(struct file *filp, struct vm_area_struct *vma) * * Poll implemention. */ -static unsigned int relay_file_poll(struct file *filp, poll_table *wait) +static __poll_t relay_file_poll(struct file *filp, poll_table *wait) { - unsigned int mask = 0; + __poll_t mask = 0; struct rchan_buf *buf = filp->private_data; if (buf->finalized) diff --git a/kernel/resource.c b/kernel/resource.c index 54ba6de..8c527d8 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1022,6 +1022,7 @@ static void __init __reserve_region_with_split(struct resource *root, struct resource *conflict; struct resource *res = alloc_resource(GFP_ATOMIC); struct resource *next_res = NULL; + int type = resource_type(root); if (!res) return; @@ -1029,7 +1030,7 @@ static void __init __reserve_region_with_split(struct resource *root, res->name = name; res->start = start; res->end = end; - res->flags = IORESOURCE_BUSY; + res->flags = type | IORESOURCE_BUSY; res->desc = IORES_DESC_NONE; while (1) { @@ -1064,7 +1065,7 @@ static void __init __reserve_region_with_split(struct resource *root, next_res->name = name; next_res->start = conflict->end + 1; next_res->end = end; - next_res->flags = IORESOURCE_BUSY; + next_res->flags = type | IORESOURCE_BUSY; next_res->desc = IORES_DESC_NONE; } } else { @@ -1478,7 +1479,7 @@ void __devm_release_region(struct device *dev, struct resource *parent, EXPORT_SYMBOL(__devm_release_region); /* - * Called from init/main.c to reserve IO ports. + * Reserve I/O ports or memory based on "reserve=" kernel parameter. */ #define MAXRESERVE 4 static int __init reserve_setup(char *str) @@ -1489,26 +1490,38 @@ static int __init reserve_setup(char *str) for (;;) { unsigned int io_start, io_num; int x = reserved; + struct resource *parent; - if (get_option (&str, &io_start) != 2) + if (get_option(&str, &io_start) != 2) break; - if (get_option (&str, &io_num) == 0) + if (get_option(&str, &io_num) == 0) break; if (x < MAXRESERVE) { struct resource *res = reserve + x; + + /* + * If the region starts below 0x10000, we assume it's + * I/O port space; otherwise assume it's memory. + */ + if (io_start < 0x10000) { + res->flags = IORESOURCE_IO; + parent = &ioport_resource; + } else { + res->flags = IORESOURCE_MEM; + parent = &iomem_resource; + } res->name = "reserved"; res->start = io_start; res->end = io_start + io_num - 1; - res->flags = IORESOURCE_BUSY; + res->flags |= IORESOURCE_BUSY; res->desc = IORES_DESC_NONE; res->child = NULL; - if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) + if (request_resource(parent, res) == 0) reserved = x+1; } } return 1; } - __setup("reserve=", reserve_setup); /* diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c index a43df51..bb4b9fe 100644 --- a/kernel/sched/autogroup.c +++ b/kernel/sched/autogroup.c @@ -1,13 +1,12 @@ // SPDX-License-Identifier: GPL-2.0 -#include "sched.h" - #include <linux/proc_fs.h> #include <linux/seq_file.h> -#include <linux/kallsyms.h> #include <linux/utsname.h> #include <linux/security.h> #include <linux/export.h> +#include "sched.h" + unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1; static struct autogroup autogroup_default; static atomic_t autogroup_seq_nr; diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 5f0dfb2ab..940fa40 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -515,7 +515,7 @@ void put_seccomp_filter(struct task_struct *tsk) static void seccomp_init_siginfo(siginfo_t *info, int syscall, int reason) { - memset(info, 0, sizeof(*info)); + clear_siginfo(info); info->si_signo = SIGSYS; info->si_code = SYS_SECCOMP; info->si_call_addr = (void __user *)KSTK_EIP(current); @@ -978,49 +978,68 @@ long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter) } #if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE) -long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, - void __user *data) +static struct seccomp_filter *get_nth_filter(struct task_struct *task, + unsigned long filter_off) { - struct seccomp_filter *filter; - struct sock_fprog_kern *fprog; - long ret; - unsigned long count = 0; - - if (!capable(CAP_SYS_ADMIN) || - current->seccomp.mode != SECCOMP_MODE_DISABLED) { - return -EACCES; - } + struct seccomp_filter *orig, *filter; + unsigned long count; + /* + * Note: this is only correct because the caller should be the (ptrace) + * tracer of the task, otherwise lock_task_sighand is needed. + */ spin_lock_irq(&task->sighand->siglock); + if (task->seccomp.mode != SECCOMP_MODE_FILTER) { - ret = -EINVAL; - goto out; + spin_unlock_irq(&task->sighand->siglock); + return ERR_PTR(-EINVAL); } - filter = task->seccomp.filter; - while (filter) { - filter = filter->prev; + orig = task->seccomp.filter; + __get_seccomp_filter(orig); + spin_unlock_irq(&task->sighand->siglock); + + count = 0; + for (filter = orig; filter; filter = filter->prev) count++; - } if (filter_off >= count) { - ret = -ENOENT; + filter = ERR_PTR(-ENOENT); goto out; } - count -= filter_off; - filter = task->seccomp.filter; - while (filter && count > 1) { - filter = filter->prev; + count -= filter_off; + for (filter = orig; filter && count > 1; filter = filter->prev) count--; - } if (WARN_ON(count != 1 || !filter)) { - /* The filter tree shouldn't shrink while we're using it. */ - ret = -ENOENT; + filter = ERR_PTR(-ENOENT); goto out; } + __get_seccomp_filter(filter); + +out: + __put_seccomp_filter(orig); + return filter; +} + +long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, + void __user *data) +{ + struct seccomp_filter *filter; + struct sock_fprog_kern *fprog; + long ret; + + if (!capable(CAP_SYS_ADMIN) || + current->seccomp.mode != SECCOMP_MODE_DISABLED) { + return -EACCES; + } + + filter = get_nth_filter(task, filter_off); + if (IS_ERR(filter)) + return PTR_ERR(filter); + fprog = filter->prog->orig_prog; if (!fprog) { /* This must be a new non-cBPF filter, since we save @@ -1035,17 +1054,44 @@ long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, if (!data) goto out; - __get_seccomp_filter(filter); - spin_unlock_irq(&task->sighand->siglock); - if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog))) ret = -EFAULT; +out: __put_seccomp_filter(filter); return ret; +} -out: - spin_unlock_irq(&task->sighand->siglock); +long seccomp_get_metadata(struct task_struct *task, + unsigned long size, void __user *data) +{ + long ret; + struct seccomp_filter *filter; + struct seccomp_metadata kmd = {}; + + if (!capable(CAP_SYS_ADMIN) || + current->seccomp.mode != SECCOMP_MODE_DISABLED) { + return -EACCES; + } + + size = min_t(unsigned long, size, sizeof(kmd)); + + if (copy_from_user(&kmd, data, size)) + return -EFAULT; + + filter = get_nth_filter(task, kmd.filter_off); + if (IS_ERR(filter)) + return PTR_ERR(filter); + + memset(&kmd, 0, sizeof(kmd)); + if (filter->log) + kmd.flags |= SECCOMP_FILTER_FLAG_LOG; + + ret = size; + if (copy_to_user(data, &kmd, size)) + ret = -EFAULT; + + __put_seccomp_filter(filter); return ret; } #endif diff --git a/kernel/signal.c b/kernel/signal.c index 9558664..c6e4c83 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -40,6 +40,7 @@ #include <linux/cn_proc.h> #include <linux/compiler.h> #include <linux/posix-timers.h> +#include <linux/livepatch.h> #define CREATE_TRACE_POINTS #include <trace/events/signal.h> @@ -165,7 +166,8 @@ void recalc_sigpending_and_wake(struct task_struct *t) void recalc_sigpending(void) { - if (!recalc_sigpending_tsk(current) && !freezing(current)) + if (!recalc_sigpending_tsk(current) && !freezing(current) && + !klp_patch_pending(current)) clear_thread_flag(TIF_SIGPENDING); } @@ -549,6 +551,7 @@ still_pending: * a fast-pathed signal or we must have been * out of queue space. So zero out the info. */ + clear_siginfo(info); info->si_signo = sig; info->si_errno = 0; info->si_code = SI_USER; @@ -642,6 +645,9 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) spin_unlock(&tsk->sighand->siglock); posixtimer_rearm(info); spin_lock(&tsk->sighand->siglock); + + /* Don't expose the si_sys_private value to userspace */ + info->si_sys_private = 0; } #endif return signr; @@ -1043,6 +1049,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, list_add_tail(&q->list, &pending->list); switch ((unsigned long) info) { case (unsigned long) SEND_SIG_NOINFO: + clear_siginfo(&q->info); q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_USER; @@ -1051,6 +1058,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid()); break; case (unsigned long) SEND_SIG_PRIV: + clear_siginfo(&q->info); q->info.si_signo = sig; q->info.si_errno = 0; q->info.si_code = SI_KERNEL; @@ -1485,6 +1493,129 @@ force_sigsegv(int sig, struct task_struct *p) return 0; } +int force_sig_fault(int sig, int code, void __user *addr + ___ARCH_SI_TRAPNO(int trapno) + ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) + , struct task_struct *t) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = sig; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; +#ifdef __ARCH_SI_TRAPNO + info.si_trapno = trapno; +#endif +#ifdef __ia64__ + info.si_imm = imm; + info.si_flags = flags; + info.si_isr = isr; +#endif + return force_sig_info(info.si_signo, &info, t); +} + +int send_sig_fault(int sig, int code, void __user *addr + ___ARCH_SI_TRAPNO(int trapno) + ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) + , struct task_struct *t) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = sig; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; +#ifdef __ARCH_SI_TRAPNO + info.si_trapno = trapno; +#endif +#ifdef __ia64__ + info.si_imm = imm; + info.si_flags = flags; + info.si_isr = isr; +#endif + return send_sig_info(info.si_signo, &info, t); +} + +#if defined(BUS_MCEERR_AO) && defined(BUS_MCEERR_AR) +int force_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t) +{ + struct siginfo info; + + WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); + clear_siginfo(&info); + info.si_signo = SIGBUS; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; + info.si_addr_lsb = lsb; + return force_sig_info(info.si_signo, &info, t); +} + +int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t) +{ + struct siginfo info; + + WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR)); + clear_siginfo(&info); + info.si_signo = SIGBUS; + info.si_errno = 0; + info.si_code = code; + info.si_addr = addr; + info.si_addr_lsb = lsb; + return send_sig_info(info.si_signo, &info, t); +} +EXPORT_SYMBOL(send_sig_mceerr); +#endif + +#ifdef SEGV_BNDERR +int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = 0; + info.si_code = SEGV_BNDERR; + info.si_addr = addr; + info.si_lower = lower; + info.si_upper = upper; + return force_sig_info(info.si_signo, &info, current); +} +#endif + +#ifdef SEGV_PKUERR +int force_sig_pkuerr(void __user *addr, u32 pkey) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = 0; + info.si_code = SEGV_PKUERR; + info.si_addr = addr; + info.si_pkey = pkey; + return force_sig_info(info.si_signo, &info, current); +} +#endif + +/* For the crazy architectures that include trap information in + * the errno field, instead of an actual errno value. + */ +int force_sig_ptrace_errno_trap(int errno, void __user *addr) +{ + struct siginfo info; + + clear_siginfo(&info); + info.si_signo = SIGTRAP; + info.si_errno = errno; + info.si_code = TRAP_HWBKPT; + info.si_addr = addr; + return force_sig_info(info.si_signo, &info, current); +} + int kill_pgrp(struct pid *pid, int sig, int priv) { int ret; @@ -1623,6 +1754,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig) sig = SIGCHLD; } + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; /* @@ -1717,6 +1849,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, parent = tsk->real_parent; } + clear_siginfo(&info); info.si_signo = SIGCHLD; info.si_errno = 0; /* @@ -1929,7 +2062,7 @@ static void ptrace_do_notify(int signr, int exit_code, int why) { siginfo_t info; - memset(&info, 0, sizeof info); + clear_siginfo(&info); info.si_signo = signr; info.si_code = exit_code; info.si_pid = task_pid_vnr(current); @@ -2136,6 +2269,7 @@ static int ptrace_signal(int signr, siginfo_t *info) * have updated *info via PTRACE_SETSIGINFO. */ if (signr != info->si_signo) { + clear_siginfo(info); info->si_signo = signr; info->si_errno = 0; info->si_code = SI_USER; @@ -2688,9 +2822,7 @@ enum siginfo_layout siginfo_layout(int sig, int si_code) #endif [SIGCHLD] = { NSIGCHLD, SIL_CHLD }, [SIGPOLL] = { NSIGPOLL, SIL_POLL }, -#ifdef __ARCH_SIGSYS [SIGSYS] = { NSIGSYS, SIL_SYS }, -#endif }; if ((sig < ARRAY_SIZE(filter)) && (si_code <= filter[sig].limit)) layout = filter[sig].layout; @@ -2712,12 +2844,14 @@ enum siginfo_layout siginfo_layout(int sig, int si_code) if ((sig == SIGFPE) && (si_code == FPE_FIXME)) layout = SIL_FAULT; #endif +#ifdef BUS_FIXME + if ((sig == SIGBUS) && (si_code == BUS_FIXME)) + layout = SIL_FAULT; +#endif } return layout; } -#ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER - int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) { int err; @@ -2756,13 +2890,21 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) #ifdef __ARCH_SI_TRAPNO err |= __put_user(from->si_trapno, &to->si_trapno); #endif -#ifdef BUS_MCEERR_AO +#ifdef __ia64__ + err |= __put_user(from->si_imm, &to->si_imm); + err |= __put_user(from->si_flags, &to->si_flags); + err |= __put_user(from->si_isr, &to->si_isr); +#endif /* * Other callers might not initialize the si_lsb field, * so check explicitly for the right codes here. */ - if (from->si_signo == SIGBUS && - (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)) +#ifdef BUS_MCEERR_AR + if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AR) + err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); +#endif +#ifdef BUS_MCEERR_AO + if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AO) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); #endif #ifdef SEGV_BNDERR @@ -2788,18 +2930,185 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) err |= __put_user(from->si_uid, &to->si_uid); err |= __put_user(from->si_ptr, &to->si_ptr); break; -#ifdef __ARCH_SIGSYS case SIL_SYS: err |= __put_user(from->si_call_addr, &to->si_call_addr); err |= __put_user(from->si_syscall, &to->si_syscall); err |= __put_user(from->si_arch, &to->si_arch); break; -#endif } return err; } +#ifdef CONFIG_COMPAT +int copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct siginfo *from) +#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION) +{ + return __copy_siginfo_to_user32(to, from, in_x32_syscall()); +} +int __copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct siginfo *from, bool x32_ABI) +#endif +{ + struct compat_siginfo new; + memset(&new, 0, sizeof(new)); + + new.si_signo = from->si_signo; + new.si_errno = from->si_errno; + new.si_code = from->si_code; + switch(siginfo_layout(from->si_signo, from->si_code)) { + case SIL_KILL: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + break; + case SIL_TIMER: + new.si_tid = from->si_tid; + new.si_overrun = from->si_overrun; + new.si_int = from->si_int; + break; + case SIL_POLL: + new.si_band = from->si_band; + new.si_fd = from->si_fd; + break; + case SIL_FAULT: + new.si_addr = ptr_to_compat(from->si_addr); +#ifdef __ARCH_SI_TRAPNO + new.si_trapno = from->si_trapno; +#endif +#ifdef BUS_MCEERR_AR + if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AR)) + new.si_addr_lsb = from->si_addr_lsb; +#endif +#ifdef BUS_MCEERR_AO + if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO)) + new.si_addr_lsb = from->si_addr_lsb; +#endif +#ifdef SEGV_BNDERR + if ((from->si_signo == SIGSEGV) && + (from->si_code == SEGV_BNDERR)) { + new.si_lower = ptr_to_compat(from->si_lower); + new.si_upper = ptr_to_compat(from->si_upper); + } +#endif +#ifdef SEGV_PKUERR + if ((from->si_signo == SIGSEGV) && + (from->si_code == SEGV_PKUERR)) + new.si_pkey = from->si_pkey; +#endif + + break; + case SIL_CHLD: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + new.si_status = from->si_status; +#ifdef CONFIG_X86_X32_ABI + if (x32_ABI) { + new._sifields._sigchld_x32._utime = from->si_utime; + new._sifields._sigchld_x32._stime = from->si_stime; + } else +#endif + { + new.si_utime = from->si_utime; + new.si_stime = from->si_stime; + } + break; + case SIL_RT: + new.si_pid = from->si_pid; + new.si_uid = from->si_uid; + new.si_int = from->si_int; + break; + case SIL_SYS: + new.si_call_addr = ptr_to_compat(from->si_call_addr); + new.si_syscall = from->si_syscall; + new.si_arch = from->si_arch; + break; + } + + if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) + return -EFAULT; + + return 0; +} + +int copy_siginfo_from_user32(struct siginfo *to, + const struct compat_siginfo __user *ufrom) +{ + struct compat_siginfo from; + + if (copy_from_user(&from, ufrom, sizeof(struct compat_siginfo))) + return -EFAULT; + + clear_siginfo(to); + to->si_signo = from.si_signo; + to->si_errno = from.si_errno; + to->si_code = from.si_code; + switch(siginfo_layout(from.si_signo, from.si_code)) { + case SIL_KILL: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + break; + case SIL_TIMER: + to->si_tid = from.si_tid; + to->si_overrun = from.si_overrun; + to->si_int = from.si_int; + break; + case SIL_POLL: + to->si_band = from.si_band; + to->si_fd = from.si_fd; + break; + case SIL_FAULT: + to->si_addr = compat_ptr(from.si_addr); +#ifdef __ARCH_SI_TRAPNO + to->si_trapno = from.si_trapno; +#endif +#ifdef BUS_MCEERR_AR + if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AR)) + to->si_addr_lsb = from.si_addr_lsb; +#endif +#ifdef BUS_MCEER_AO + if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO)) + to->si_addr_lsb = from.si_addr_lsb; +#endif +#ifdef SEGV_BNDERR + if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) { + to->si_lower = compat_ptr(from.si_lower); + to->si_upper = compat_ptr(from.si_upper); + } +#endif +#ifdef SEGV_PKUERR + if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_PKUERR)) + to->si_pkey = from.si_pkey; +#endif + break; + case SIL_CHLD: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + to->si_status = from.si_status; +#ifdef CONFIG_X86_X32_ABI + if (in_x32_syscall()) { + to->si_utime = from._sifields._sigchld_x32._utime; + to->si_stime = from._sifields._sigchld_x32._stime; + } else #endif + { + to->si_utime = from.si_utime; + to->si_stime = from.si_stime; + } + break; + case SIL_RT: + to->si_pid = from.si_pid; + to->si_uid = from.si_uid; + to->si_int = from.si_int; + break; + case SIL_SYS: + to->si_call_addr = compat_ptr(from.si_call_addr); + to->si_syscall = from.si_syscall; + to->si_arch = from.si_arch; + break; + } + return 0; +} +#endif /* CONFIG_COMPAT */ /** * do_sigtimedwait - wait for queued signals specified in @which @@ -2937,6 +3246,7 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) { struct siginfo info; + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; info.si_code = SI_USER; @@ -2978,8 +3288,9 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info) static int do_tkill(pid_t tgid, pid_t pid, int sig) { - struct siginfo info = {}; + struct siginfo info; + clear_siginfo(&info); info.si_signo = sig; info.si_errno = 0; info.si_code = SI_TKILL; @@ -3060,7 +3371,7 @@ COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo, int, sig, struct compat_siginfo __user *, uinfo) { - siginfo_t info = {}; + siginfo_t info; int ret = copy_siginfo_from_user32(&info, uinfo); if (unlikely(ret)) return ret; @@ -3104,7 +3415,7 @@ COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo, int, sig, struct compat_siginfo __user *, uinfo) { - siginfo_t info = {}; + siginfo_t info; if (copy_siginfo_from_user32(&info, uinfo)) return -EFAULT; @@ -3677,6 +3988,7 @@ void __init signals_init(void) /* If this check fails, the __ARCH_SI_PREAMBLE_SIZE value is wrong! */ BUILD_BUG_ON(__ARCH_SI_PREAMBLE_SIZE != offsetof(struct siginfo, _sifields._pad)); + BUILD_BUG_ON(sizeof(struct siginfo) != SI_MAX_SIZE); sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC); } @@ -3684,26 +3996,25 @@ void __init signals_init(void) #ifdef CONFIG_KGDB_KDB #include <linux/kdb.h> /* - * kdb_send_sig_info - Allows kdb to send signals without exposing + * kdb_send_sig - Allows kdb to send signals without exposing * signal internals. This function checks if the required locks are * available before calling the main signal code, to avoid kdb * deadlocks. */ -void -kdb_send_sig_info(struct task_struct *t, struct siginfo *info) +void kdb_send_sig(struct task_struct *t, int sig) { static struct task_struct *kdb_prev_t; - int sig, new_t; + int new_t, ret; if (!spin_trylock(&t->sighand->siglock)) { kdb_printf("Can't do kill command now.\n" "The sigmask lock is held somewhere else in " "kernel, try again later\n"); return; } - spin_unlock(&t->sighand->siglock); new_t = kdb_prev_t != t; kdb_prev_t = t; if (t->state != TASK_RUNNING && new_t) { + spin_unlock(&t->sighand->siglock); kdb_printf("Process is not RUNNING, sending a signal from " "kdb risks deadlock\n" "on the run queue locks. " @@ -3712,8 +4023,9 @@ kdb_send_sig_info(struct task_struct *t, struct siginfo *info) "the deadlock.\n"); return; } - sig = info->si_signo; - if (send_sig_info(sig, info, t)) + ret = send_signal(sig, SEND_SIG_PRIV, t, false); + spin_unlock(&t->sighand->siglock); + if (ret) kdb_printf("Fail to deliver Signal %d to process %d.\n", sig, t->pid); else diff --git a/kernel/sys.c b/kernel/sys.c index 83ffd7d..f2289de 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -135,7 +135,7 @@ EXPORT_SYMBOL(overflowgid); */ int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; -int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; +int fs_overflowgid = DEFAULT_FS_OVERFLOWGID; EXPORT_SYMBOL(fs_overflowuid); EXPORT_SYMBOL(fs_overflowgid); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 557d467..2fb4e27 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1374,13 +1374,6 @@ static struct ctl_table vm_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { - .procname = "hugepages_treat_as_movable", - .data = &hugepages_treat_as_movable, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, { .procname = "nr_overcommit_hugepages", .data = NULL, diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c index cc91d90..94ad46d 100644 --- a/kernel/time/posix-clock.c +++ b/kernel/time/posix-clock.c @@ -68,10 +68,10 @@ static ssize_t posix_clock_read(struct file *fp, char __user *buf, return err; } -static unsigned int posix_clock_poll(struct file *fp, poll_table *wait) +static __poll_t posix_clock_poll(struct file *fp, poll_table *wait) { struct posix_clock *clk = get_posix_clock(fp); - unsigned int result = 0; + __poll_t result = 0; if (!clk) return POLLERR; diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index ec999f3..7504304 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -462,7 +462,7 @@ static struct k_itimer * alloc_posix_timer(void) kmem_cache_free(posix_timers_cache, tmr); return NULL; } - memset(&tmr->sigq->info, 0, sizeof(siginfo_t)); + clear_siginfo(&tmr->sigq->info); return tmr; } diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index f54dc62..0b249e2 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -530,6 +530,15 @@ config FUNCTION_PROFILER If in doubt, say N. +config BPF_KPROBE_OVERRIDE + bool "Enable BPF programs to override a kprobed function" + depends on BPF_EVENTS + depends on FUNCTION_ERROR_INJECTION + default n + help + Allows BPF to override the execution of a probed function and + set a different return value. This is used for error injection. + config FTRACE_MCOUNT_RECORD def_bool y depends on DYNAMIC_FTRACE diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 40207c2..fc2838a 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -13,6 +13,10 @@ #include <linux/filter.h> #include <linux/uaccess.h> #include <linux/ctype.h> +#include <linux/kprobes.h> +#include <linux/error-injection.h> + +#include "trace_probe.h" #include "trace.h" u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); @@ -76,6 +80,23 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) } EXPORT_SYMBOL_GPL(trace_call_bpf); +#ifdef CONFIG_BPF_KPROBE_OVERRIDE +BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc) +{ + regs_set_return_value(regs, rc); + override_function_with_return(regs); + return 0; +} + +static const struct bpf_func_proto bpf_override_return_proto = { + .func = bpf_override_return, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, +}; +#endif + BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr) { int ret; @@ -224,7 +245,7 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, */ #define __BPF_TP_EMIT() __BPF_ARG3_TP() #define __BPF_TP(...) \ - __trace_printk(1 /* Fake ip will not be printed. */, \ + __trace_printk(0 /* Fake ip */, \ fmt, ##__VA_ARGS__) #define __BPF_ARG1_TP(...) \ @@ -556,6 +577,10 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func return &bpf_get_stackid_proto; case BPF_FUNC_perf_event_read_value: return &bpf_perf_event_read_value_proto; +#ifdef CONFIG_BPF_KPROBE_OVERRIDE + case BPF_FUNC_override_return: + return &bpf_override_return_proto; +#endif default: return tracing_func_proto(func_id); } @@ -773,6 +798,15 @@ int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog_array *new_array; int ret = -EEXIST; + /* + * Kprobe override only works if they are on the function entry, + * and only if they are on the opt-in list. + */ + if (prog->kprobe_override && + (!trace_kprobe_on_func_entry(event->tp_event) || + !trace_kprobe_error_injectable(event->tp_event))) + return -EINVAL; + mutex_lock(&bpf_event_mutex); if (event->prog) @@ -825,3 +859,26 @@ void perf_event_detach_bpf_prog(struct perf_event *event) unlock: mutex_unlock(&bpf_event_mutex); } + +int perf_event_query_prog_array(struct perf_event *event, void __user *info) +{ + struct perf_event_query_bpf __user *uquery = info; + struct perf_event_query_bpf query = {}; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (event->attr.type != PERF_TYPE_TRACEPOINT) + return -EINVAL; + if (copy_from_user(&query, uquery, sizeof(query))) + return -EFAULT; + + mutex_lock(&bpf_event_mutex); + ret = bpf_prog_array_copy_info(event->tp_event->prog_array, + uquery->ids, + query.ids_len, + &uquery->prog_cnt); + mutex_unlock(&bpf_event_mutex); + + return ret; +} diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 554b517..dabd9d1 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5015,7 +5015,6 @@ int ftrace_regex_release(struct inode *inode, struct file *file) parser = &iter->parser; if (trace_parser_loaded(parser)) { - parser->buffer[parser->idx] = 0; ftrace_match_records(iter->hash, parser->buffer, parser->idx); } @@ -5329,7 +5328,6 @@ ftrace_graph_release(struct inode *inode, struct file *file) parser = &fgd->parser; if (trace_parser_loaded((parser))) { - parser->buffer[parser->idx] = 0; ret = ftrace_graph_set_hash(fgd->new_hash, parser->buffer); } diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 5af2842..ca6930e 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -630,7 +630,7 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full) * Returns POLLIN | POLLRDNORM if data exists in the buffers, * zero otherwise. */ -int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, +__poll_t ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, struct file *filp, poll_table *poll_table) { struct ring_buffer_per_cpu *cpu_buffer; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 4f3a8e2..5660853 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -530,8 +530,6 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, ubuf += ret; cnt -= ret; - parser.buffer[parser.idx] = 0; - ret = -EINVAL; if (kstrtoul(parser.buffer, 0, &val)) break; @@ -1236,18 +1234,18 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf, cnt--; } + parser->idx = 0; + /* only spaces were written */ - if (isspace(ch)) { + if (isspace(ch) || !ch) { *ppos += read; ret = read; goto out; } - - parser->idx = 0; } /* read the non-space input */ - while (cnt && !isspace(ch)) { + while (cnt && !isspace(ch) && ch) { if (parser->idx < parser->size - 1) parser->buffer[parser->idx++] = ch; else { @@ -1262,12 +1260,14 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf, } /* We either got finished input or we have to wait for another call. */ - if (isspace(ch)) { + if (isspace(ch) || !ch) { parser->buffer[parser->idx] = 0; parser->cont = false; } else if (parser->idx < parser->size - 1) { parser->cont = true; parser->buffer[parser->idx++] = ch; + /* Make sure the parsed string always terminates with '\0'. */ + parser->buffer[parser->idx] = 0; } else { ret = -EINVAL; goto out; @@ -5616,7 +5616,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) return 0; } -static unsigned int +static __poll_t trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) { struct trace_array *tr = iter->tr; @@ -5635,7 +5635,7 @@ trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_tabl filp, poll_table); } -static unsigned int +static __poll_t tracing_poll_pipe(struct file *filp, poll_table *poll_table) { struct trace_iterator *iter = filp->private_data; @@ -6589,7 +6589,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) return ret; } -static unsigned int +static __poll_t tracing_buffers_poll(struct file *filp, poll_table *poll_table) { struct ftrace_buffer_info *info = filp->private_data; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 1b87157..05c7172 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -885,8 +885,6 @@ ftrace_event_write(struct file *file, const char __user *ubuf, if (*parser.buffer == '!') set = 0; - parser.buffer[parser.idx] = 0; - ret = ftrace_set_clr_event(tr, parser.buffer + !set, set); if (ret) goto out_put; diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 492700c..1fad24a 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -21,6 +21,7 @@ #include <linux/module.h> #include <linux/uaccess.h> #include <linux/rculist.h> +#include <linux/error-injection.h> #include "trace_probe.h" @@ -42,7 +43,6 @@ struct trace_kprobe { (offsetof(struct trace_kprobe, tp.args) + \ (sizeof(struct probe_arg) * (n))) - static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk) { return tk->rp.handler != NULL; @@ -87,6 +87,30 @@ static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk) return nhit; } +bool trace_kprobe_on_func_entry(struct trace_event_call *call) +{ + struct trace_kprobe *tk = (struct trace_kprobe *)call->data; + + return kprobe_on_func_entry(tk->rp.kp.addr, + tk->rp.kp.addr ? NULL : tk->rp.kp.symbol_name, + tk->rp.kp.addr ? 0 : tk->rp.kp.offset); +} + +bool trace_kprobe_error_injectable(struct trace_event_call *call) +{ + struct trace_kprobe *tk = (struct trace_kprobe *)call->data; + unsigned long addr; + + if (tk->symbol) { + addr = (unsigned long) + kallsyms_lookup_name(trace_kprobe_symbol(tk)); + addr += tk->rp.kp.offset; + } else { + addr = (unsigned long)tk->rp.kp.addr; + } + return within_error_injection_list(addr); +} + static int register_kprobe_event(struct trace_kprobe *tk); static int unregister_kprobe_event(struct trace_kprobe *tk); @@ -1170,7 +1194,7 @@ static int kretprobe_event_define_fields(struct trace_event_call *event_call) #ifdef CONFIG_PERF_EVENTS /* Kprobe profile handler */ -static void +static int kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) { struct trace_event_call *call = &tk->tp.call; @@ -1179,12 +1203,31 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) int size, __size, dsize; int rctx; - if (bpf_prog_array_valid(call) && !trace_call_bpf(call, regs)) - return; + if (bpf_prog_array_valid(call)) { + unsigned long orig_ip = instruction_pointer(regs); + int ret; + + ret = trace_call_bpf(call, regs); + + /* + * We need to check and see if we modified the pc of the + * pt_regs, and if so clear the kprobe and return 1 so that we + * don't do the single stepping. + * The ftrace kprobe handler leaves it up to us to re-enable + * preemption here before returning if we've modified the ip. + */ + if (orig_ip != instruction_pointer(regs)) { + reset_current_kprobe(); + preempt_enable_no_resched(); + return 1; + } + if (!ret) + return 0; + } head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) - return; + return 0; dsize = __get_data_size(&tk->tp, regs); __size = sizeof(*entry) + tk->tp.size + dsize; @@ -1193,13 +1236,14 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) entry = perf_trace_buf_alloc(size, NULL, &rctx); if (!entry) - return; + return 0; entry->ip = (unsigned long)tk->rp.kp.addr; memset(&entry[1], 0, dsize); store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs, head, NULL); + return 0; } NOKPROBE_SYMBOL(kprobe_perf_func); @@ -1275,6 +1319,7 @@ static int kprobe_register(struct trace_event_call *event, static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) { struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); + int ret = 0; raw_cpu_inc(*tk->nhit); @@ -1282,9 +1327,9 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) kprobe_trace_func(tk, regs); #ifdef CONFIG_PERF_EVENTS if (tk->tp.flags & TP_FLAG_PROFILE) - kprobe_perf_func(tk, regs); + ret = kprobe_perf_func(tk, regs); #endif - return 0; /* We don't tweek kernel, so just return 0 */ + return ret; } NOKPROBE_SYMBOL(kprobe_dispatcher); diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index fb66e3e..e101c5b 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -252,6 +252,8 @@ struct symbol_cache; unsigned long update_symbol_cache(struct symbol_cache *sc); void free_symbol_cache(struct symbol_cache *sc); struct symbol_cache *alloc_symbol_cache(const char *sym, long offset); +bool trace_kprobe_on_func_entry(struct trace_event_call *call); +bool trace_kprobe_error_injectable(struct trace_event_call *call); #else /* uprobes do not support symbol fetch methods */ #define fetch_symbol_u8 NULL @@ -277,6 +279,16 @@ alloc_symbol_cache(const char *sym, long offset) { return NULL; } + +static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call) +{ + return false; +} + +static inline bool trace_kprobe_error_injectable(struct trace_event_call *call) +{ + return false; +} #endif /* CONFIG_KPROBE_EVENTS */ struct probe_arg { diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c index 8cda06a..c364cf7 100644 --- a/kernel/trace/trace_selftest_dynamic.c +++ b/kernel/trace/trace_selftest_dynamic.c @@ -1,13 +1,14 @@ // SPDX-License-Identifier: GPL-2.0 +#include <linux/compiler.h> #include "trace.h" -int DYN_FTRACE_TEST_NAME(void) +noinline __noclone int DYN_FTRACE_TEST_NAME(void) { /* used to call mcount */ return 0; } -int DYN_FTRACE_TEST_NAME2(void) +noinline __noclone int DYN_FTRACE_TEST_NAME2(void) { /* used to call mcount */ return 0; diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 40592e7b..268029a 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -608,7 +608,7 @@ static int probes_seq_show(struct seq_file *m, void *v) /* Don't print "0x (null)" when offset is 0 */ if (tu->offset) { - seq_printf(m, "0x%p", (void *)tu->offset); + seq_printf(m, "0x%px", (void *)tu->offset); } else { switch (sizeof(void *)) { case 4: diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 8c34981..017044c 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -3807,6 +3807,7 @@ int apply_workqueue_attrs(struct workqueue_struct *wq, return ret; } +EXPORT_SYMBOL_GPL(apply_workqueue_attrs); /** * wq_update_unbound_numa - update NUMA affinity of a wq for CPU hot[un]plug @@ -3940,6 +3941,37 @@ static int wq_clamp_max_active(int max_active, unsigned int flags, return clamp_val(max_active, 1, lim); } +/* + * Workqueues which may be used during memory reclaim should have a rescuer + * to guarantee forward progress. + */ +static int init_rescuer(struct workqueue_struct *wq) +{ + struct worker *rescuer; + int ret; + + if (!(wq->flags & WQ_MEM_RECLAIM)) + return 0; + + rescuer = alloc_worker(NUMA_NO_NODE); + if (!rescuer) + return -ENOMEM; + + rescuer->rescue_wq = wq; + rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", wq->name); + ret = PTR_ERR_OR_ZERO(rescuer->task); + if (ret) { + kfree(rescuer); + return ret; + } + + wq->rescuer = rescuer; + kthread_bind_mask(rescuer->task, cpu_possible_mask); + wake_up_process(rescuer->task); + + return 0; +} + struct workqueue_struct *__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, @@ -4002,29 +4034,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt, if (alloc_and_link_pwqs(wq) < 0) goto err_free_wq; - /* - * Workqueues which may be used during memory reclaim should - * have a rescuer to guarantee forward progress. - */ - if (flags & WQ_MEM_RECLAIM) { - struct worker *rescuer; - - rescuer = alloc_worker(NUMA_NO_NODE); - if (!rescuer) - goto err_destroy; - - rescuer->rescue_wq = wq; - rescuer->task = kthread_create(rescuer_thread, rescuer, "%s", - wq->name); - if (IS_ERR(rescuer->task)) { - kfree(rescuer); - goto err_destroy; - } - - wq->rescuer = rescuer; - kthread_bind_mask(rescuer->task, cpu_possible_mask); - wake_up_process(rescuer->task); - } + if (wq_online && init_rescuer(wq) < 0) + goto err_destroy; if ((wq->flags & WQ_SYSFS) && workqueue_sysfs_register(wq)) goto err_destroy; @@ -5642,6 +5653,8 @@ int __init workqueue_init(void) * archs such as power and arm64. As per-cpu pools created * previously could be missing node hint and unbound pools NUMA * affinity, fix them up. + * + * Also, while iterating workqueues, create rescuers if requested. */ wq_numa_init(); @@ -5653,8 +5666,12 @@ int __init workqueue_init(void) } } - list_for_each_entry(wq, &workqueues, list) + list_for_each_entry(wq, &workqueues, list) { wq_update_unbound_numa(wq, smp_processor_id(), true); + WARN(init_rescuer(wq), + "workqueue: failed to create early rescuer for %s", + wq->name); + } mutex_unlock(&wq_pool_mutex); |
