diff options
29 files changed, 681 insertions, 654 deletions
diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c index 1e4658e..5a4875ca 100644 --- a/arch/mips/mm/gup.c +++ b/arch/mips/mm/gup.c @@ -178,6 +178,8 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end, /* * Like get_user_pages_fast() except its IRQ-safe in that it won't fall * back to the regular GUP. + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 73ce5dd..c32a181 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -552,6 +552,9 @@ config KEXEC_FILE for kernel and initramfs as opposed to a list of segments as is the case for the older kexec call. +config ARCH_HAS_KEXEC_PURGATORY + def_bool KEXEC_FILE + config RELOCATABLE bool "Build a relocatable kernel" depends on PPC64 || (FLATMEM && (44x || FSL_BOOKE)) diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h index d8b1e8e..4a585cb 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -95,7 +95,7 @@ static inline bool kdump_in_progress(void) } #ifdef CONFIG_KEXEC_FILE -extern struct kexec_file_ops kexec_elf64_ops; +extern const struct kexec_file_ops kexec_elf64_ops; #ifdef CONFIG_IMA_KEXEC #define ARCH_HAS_KIMAGE_ARCH diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c index 9a42309..ba4f18a 100644 --- a/arch/powerpc/kernel/kexec_elf_64.c +++ b/arch/powerpc/kernel/kexec_elf_64.c @@ -572,7 +572,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, { int ret; unsigned int fdt_size; - unsigned long kernel_load_addr, purgatory_load_addr; + unsigned long kernel_load_addr; unsigned long initrd_load_addr = 0, fdt_load_addr; void *fdt; const void *slave_code; @@ -580,6 +580,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, struct elf_info elf_info; struct kexec_buf kbuf = { .image = image, .buf_min = 0, .buf_max = ppc64_rma_size }; + struct kexec_buf pbuf = { .image = image, .buf_min = 0, + .buf_max = ppc64_rma_size, .top_down = true }; ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info); if (ret) @@ -591,14 +593,13 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr); - ret = kexec_load_purgatory(image, 0, ppc64_rma_size, true, - &purgatory_load_addr); + ret = kexec_load_purgatory(image, &pbuf); if (ret) { pr_err("Loading purgatory failed.\n"); goto out; } - pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr); + pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem); if (initrd != NULL) { kbuf.buffer = initrd; @@ -657,7 +658,7 @@ out: return ret ? ERR_PTR(ret) : fdt; } -struct kexec_file_ops kexec_elf64_ops = { +const struct kexec_file_ops kexec_elf64_ops = { .probe = elf64_probe, .load = elf64_load, }; diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c index 45e0b7d..0bd23dc 100644 --- a/arch/powerpc/kernel/machine_kexec_file_64.c +++ b/arch/powerpc/kernel/machine_kexec_file_64.c @@ -31,52 +31,19 @@ #define SLAVE_CODE_SIZE 256 -static struct kexec_file_ops *kexec_file_loaders[] = { +const struct kexec_file_ops * const kexec_file_loaders[] = { &kexec_elf64_ops, + NULL }; int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) { - int i, ret = -ENOEXEC; - struct kexec_file_ops *fops; - /* We don't support crash kernels yet. */ if (image->type == KEXEC_TYPE_CRASH) return -EOPNOTSUPP; - for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { - fops = kexec_file_loaders[i]; - if (!fops || !fops->probe) - continue; - - ret = fops->probe(buf, buf_len); - if (!ret) { - image->fops = fops; - return ret; - } - } - - return ret; -} - -void *arch_kexec_kernel_image_load(struct kimage *image) -{ - if (!image->fops || !image->fops->load) - return ERR_PTR(-ENOEXEC); - - return image->fops->load(image, image->kernel_buf, - image->kernel_buf_len, image->initrd_buf, - image->initrd_buf_len, image->cmdline_buf, - image->cmdline_buf_len); -} - -int arch_kimage_file_post_load_cleanup(struct kimage *image) -{ - if (!image->fops || !image->fops->cleanup) - return 0; - - return image->fops->cleanup(image->image_loader_data); + return kexec_image_probe_default(image, buf, buf_len); } /** diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c index 05c8abd..2809d11 100644 --- a/arch/s390/mm/gup.c +++ b/arch/s390/mm/gup.c @@ -220,6 +220,8 @@ static inline int gup_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr, /* * Like get_user_pages_fast() except its IRQ-safe in that it won't fall * back to the regular GUP. + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) diff --git a/arch/sh/mm/gup.c b/arch/sh/mm/gup.c index 8045b5b..56c86ca 100644 --- a/arch/sh/mm/gup.c +++ b/arch/sh/mm/gup.c @@ -160,6 +160,8 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end, /* * Like get_user_pages_fast() except its IRQ-safe in that it won't fall * back to the regular GUP. + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c index 357b604..aee6dba 100644 --- a/arch/sparc/mm/gup.c +++ b/arch/sparc/mm/gup.c @@ -193,6 +193,10 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end, return 1; } +/* + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. + */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d234cca..7fe107f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2008,6 +2008,9 @@ config KEXEC_FILE for kernel and initramfs as opposed to list of segments as accepted by previous system call. +config ARCH_HAS_KEXEC_PURGATORY + def_bool KEXEC_FILE + config KEXEC_VERIFY_SIG bool "Verify kernel signature during kexec_file_load() syscall" depends on KEXEC_FILE diff --git a/arch/x86/include/asm/kexec-bzimage64.h b/arch/x86/include/asm/kexec-bzimage64.h index 9f07cff..df89ee7 100644 --- a/arch/x86/include/asm/kexec-bzimage64.h +++ b/arch/x86/include/asm/kexec-bzimage64.h @@ -2,6 +2,6 @@ #ifndef _ASM_KEXEC_BZIMAGE64_H #define _ASM_KEXEC_BZIMAGE64_H -extern struct kexec_file_ops kexec_bzImage64_ops; +extern const struct kexec_file_ops kexec_bzImage64_ops; #endif /* _ASM_KEXE_BZIMAGE64_H */ diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 1f66804..f631a3f 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -38,37 +38,6 @@ #include <asm/virtext.h> #include <asm/intel_pt.h> -/* Alignment required for elf header segment */ -#define ELF_CORE_HEADER_ALIGN 4096 - -/* This primarily represents number of split ranges due to exclusion */ -#define CRASH_MAX_RANGES 16 - -struct crash_mem_range { - u64 start, end; -}; - -struct crash_mem { - unsigned int nr_ranges; - struct crash_mem_range ranges[CRASH_MAX_RANGES]; -}; - -/* Misc data about ram ranges needed to prepare elf headers */ -struct crash_elf_data { - struct kimage *image; - /* - * Total number of ram ranges we have after various adjustments for - * crash reserved region, etc. - */ - unsigned int max_nr_ranges; - - /* Pointer to elf header */ - void *ehdr; - /* Pointer to next phdr */ - void *bufp; - struct crash_mem mem; -}; - /* Used while preparing memory map entries for second kernel */ struct crash_memmap_data { struct boot_params *params; @@ -218,124 +187,49 @@ static int get_nr_ram_ranges_callback(struct resource *res, void *arg) return 0; } - /* Gather all the required information to prepare elf headers for ram regions */ -static void fill_up_crash_elf_data(struct crash_elf_data *ced, - struct kimage *image) +static struct crash_mem *fill_up_crash_elf_data(void) { unsigned int nr_ranges = 0; - - ced->image = image; + struct crash_mem *cmem; walk_system_ram_res(0, -1, &nr_ranges, get_nr_ram_ranges_callback); + if (!nr_ranges) + return NULL; - ced->max_nr_ranges = nr_ranges; - - /* Exclusion of crash region could split memory ranges */ - ced->max_nr_ranges++; - - /* If crashk_low_res is not 0, another range split possible */ - if (crashk_low_res.end) - ced->max_nr_ranges++; -} - -static int exclude_mem_range(struct crash_mem *mem, - unsigned long long mstart, unsigned long long mend) -{ - int i, j; - unsigned long long start, end; - struct crash_mem_range temp_range = {0, 0}; - - for (i = 0; i < mem->nr_ranges; i++) { - start = mem->ranges[i].start; - end = mem->ranges[i].end; - - if (mstart > end || mend < start) - continue; - - /* Truncate any area outside of range */ - if (mstart < start) - mstart = start; - if (mend > end) - mend = end; - - /* Found completely overlapping range */ - if (mstart == start && mend == end) { - mem->ranges[i].start = 0; - mem->ranges[i].end = 0; - if (i < mem->nr_ranges - 1) { - /* Shift rest of the ranges to left */ - for (j = i; j < mem->nr_ranges - 1; j++) { - mem->ranges[j].start = - mem->ranges[j+1].start; - mem->ranges[j].end = - mem->ranges[j+1].end; - } - } - mem->nr_ranges--; - return 0; - } - - if (mstart > start && mend < end) { - /* Split original range */ - mem->ranges[i].end = mstart - 1; - temp_range.start = mend + 1; - temp_range.end = end; - } else if (mstart != start) - mem->ranges[i].end = mstart - 1; - else - mem->ranges[i].start = mend + 1; - break; - } + /* + * Exclusion of crash region and/or crashk_low_res may cause + * another range split. So add extra two slots here. + */ + nr_ranges += 2; + cmem = vzalloc(sizeof(struct crash_mem) + + sizeof(struct crash_mem_range) * nr_ranges); + if (!cmem) + return NULL; - /* If a split happend, add the split to array */ - if (!temp_range.end) - return 0; + cmem->max_nr_ranges = nr_ranges; + cmem->nr_ranges = 0; - /* Split happened */ - if (i == CRASH_MAX_RANGES - 1) { - pr_err("Too many crash ranges after split\n"); - return -ENOMEM; - } - - /* Location where new range should go */ - j = i + 1; - if (j < mem->nr_ranges) { - /* Move over all ranges one slot towards the end */ - for (i = mem->nr_ranges - 1; i >= j; i--) - mem->ranges[i + 1] = mem->ranges[i]; - } - - mem->ranges[j].start = temp_range.start; - mem->ranges[j].end = temp_range.end; - mem->nr_ranges++; - return 0; + return cmem; } /* * Look for any unwanted ranges between mstart, mend and remove them. This - * might lead to split and split ranges are put in ced->mem.ranges[] array + * might lead to split and split ranges are put in cmem->ranges[] array */ -static int elf_header_exclude_ranges(struct crash_elf_data *ced, - unsigned long long mstart, unsigned long long mend) +static int elf_header_exclude_ranges(struct crash_mem *cmem) { - struct crash_mem *cmem = &ced->mem; int ret = 0; - memset(cmem->ranges, 0, sizeof(cmem->ranges)); - - cmem->ranges[0].start = mstart; - cmem->ranges[0].end = mend; - cmem->nr_ranges = 1; - /* Exclude crashkernel region */ - ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end); + ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); if (ret) return ret; if (crashk_low_res.end) { - ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end); + ret = crash_exclude_mem_range(cmem, crashk_low_res.start, + crashk_low_res.end); if (ret) return ret; } @@ -345,144 +239,12 @@ static int elf_header_exclude_ranges(struct crash_elf_data *ced, static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg) { - struct crash_elf_data *ced = arg; - Elf64_Ehdr *ehdr; - Elf64_Phdr *phdr; - unsigned long mstart, mend; - struct kimage *image = ced->image; - struct crash_mem *cmem; - int ret, i; - - ehdr = ced->ehdr; - - /* Exclude unwanted mem ranges */ - ret = elf_header_exclude_ranges(ced, res->start, res->end); - if (ret) - return ret; - - /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */ - cmem = &ced->mem; - - for (i = 0; i < cmem->nr_ranges; i++) { - mstart = cmem->ranges[i].start; - mend = cmem->ranges[i].end; - - phdr = ced->bufp; - ced->bufp += sizeof(Elf64_Phdr); - - phdr->p_type = PT_LOAD; - phdr->p_flags = PF_R|PF_W|PF_X; - phdr->p_offset = mstart; - - /* - * If a range matches backup region, adjust offset to backup - * segment. - */ - if (mstart == image->arch.backup_src_start && - (mend - mstart + 1) == image->arch.backup_src_sz) - phdr->p_offset = image->arch.backup_load_addr; - - phdr->p_paddr = mstart; - phdr->p_vaddr = (unsigned long long) __va(mstart); - phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; - phdr->p_align = 0; - ehdr->e_phnum++; - pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n", - phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, - ehdr->e_phnum, phdr->p_offset); - } - - return ret; -} - -static int prepare_elf64_headers(struct crash_elf_data *ced, - void **addr, unsigned long *sz) -{ - Elf64_Ehdr *ehdr; - Elf64_Phdr *phdr; - unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; - unsigned char *buf, *bufp; - unsigned int cpu; - unsigned long long notes_addr; - int ret; + struct crash_mem *cmem = arg; - /* extra phdr for vmcoreinfo elf note */ - nr_phdr = nr_cpus + 1; - nr_phdr += ced->max_nr_ranges; - - /* - * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping - * area on x86_64 (ffffffff80000000 - ffffffffa0000000). - * I think this is required by tools like gdb. So same physical - * memory will be mapped in two elf headers. One will contain kernel - * text virtual addresses and other will have __va(physical) addresses. - */ + cmem->ranges[cmem->nr_ranges].start = res->start; + cmem->ranges[cmem->nr_ranges].end = res->end; + cmem->nr_ranges++; - nr_phdr++; - elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr); - elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN); - - buf = vzalloc(elf_sz); - if (!buf) - return -ENOMEM; - - bufp = buf; - ehdr = (Elf64_Ehdr *)bufp; - bufp += sizeof(Elf64_Ehdr); - memcpy(ehdr->e_ident, ELFMAG, SELFMAG); - ehdr->e_ident[EI_CLASS] = ELFCLASS64; - ehdr->e_ident[EI_DATA] = ELFDATA2LSB; - ehdr->e_ident[EI_VERSION] = EV_CURRENT; - ehdr->e_ident[EI_OSABI] = ELF_OSABI; - memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); - ehdr->e_type = ET_CORE; - ehdr->e_machine = ELF_ARCH; - ehdr->e_version = EV_CURRENT; - ehdr->e_phoff = sizeof(Elf64_Ehdr); - ehdr->e_ehsize = sizeof(Elf64_Ehdr); - ehdr->e_phentsize = sizeof(Elf64_Phdr); - - /* Prepare one phdr of type PT_NOTE for each present cpu */ - for_each_present_cpu(cpu) { - phdr = (Elf64_Phdr *)bufp; - bufp += sizeof(Elf64_Phdr); - phdr->p_type = PT_NOTE; - notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu)); - phdr->p_offset = phdr->p_paddr = notes_addr; - phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t); - (ehdr->e_phnum)++; - } - - /* Prepare one PT_NOTE header for vmcoreinfo */ - phdr = (Elf64_Phdr *)bufp; - bufp += sizeof(Elf64_Phdr); - phdr->p_type = PT_NOTE; - phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note(); - phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; - (ehdr->e_phnum)++; - -#ifdef CONFIG_X86_64 - /* Prepare PT_LOAD type program header for kernel text region */ - phdr = (Elf64_Phdr *)bufp; - bufp += sizeof(Elf64_Phdr); - phdr->p_type = PT_LOAD; - phdr->p_flags = PF_R|PF_W|PF_X; - phdr->p_vaddr = (Elf64_Addr)_text; - phdr->p_filesz = phdr->p_memsz = _end - _text; - phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); - (ehdr->e_phnum)++; -#endif - - /* Prepare PT_LOAD headers for system ram chunks. */ - ced->ehdr = ehdr; - ced->bufp = bufp; - ret = walk_system_ram_res(0, -1, ced, - prepare_elf64_ram_headers_callback); - if (ret < 0) - return ret; - - *addr = buf; - *sz = elf_sz; return 0; } @@ -490,18 +252,46 @@ static int prepare_elf64_headers(struct crash_elf_data *ced, static int prepare_elf_headers(struct kimage *image, void **addr, unsigned long *sz) { - struct crash_elf_data *ced; - int ret; + struct crash_mem *cmem; + Elf64_Ehdr *ehdr; + Elf64_Phdr *phdr; + int ret, i; - ced = kzalloc(sizeof(*ced), GFP_KERNEL); - if (!ced) + cmem = fill_up_crash_elf_data(); + if (!cmem) return -ENOMEM; - fill_up_crash_elf_data(ced, image); + ret = walk_system_ram_res(0, -1, cmem, + prepare_elf64_ram_headers_callback); + if (ret) + goto out; + + /* Exclude unwanted mem ranges */ + ret = elf_header_exclude_ranges(cmem); + if (ret) + goto out; /* By default prepare 64bit headers */ - ret = prepare_elf64_headers(ced, addr, sz); - kfree(ced); + ret = crash_prepare_elf64_headers(cmem, + IS_ENABLED(CONFIG_X86_64), addr, sz); + if (ret) + goto out; + + /* + * If a range matches backup region, adjust offset to backup + * segment. + */ + ehdr = (Elf64_Ehdr *)*addr; + phdr = (Elf64_Phdr *)(ehdr + 1); + for (i = 0; i < ehdr->e_phnum; phdr++, i++) + if (phdr->p_type == PT_LOAD && + phdr->p_paddr == image->arch.backup_src_start && + phdr->p_memsz == image->arch.backup_src_sz) { + phdr->p_offset = image->arch.backup_load_addr; + break; + } +out: + vfree(cmem); return ret; } @@ -547,14 +337,14 @@ static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem, /* Exclude Backup region */ start = image->arch.backup_load_addr; end = start + image->arch.backup_src_sz - 1; - ret = exclude_mem_range(cmem, start, end); + ret = crash_exclude_mem_range(cmem, start, end); if (ret) return ret; /* Exclude elf header region */ start = image->arch.elf_load_addr; end = start + image->arch.elf_headers_sz - 1; - return exclude_mem_range(cmem, start, end); + return crash_exclude_mem_range(cmem, start, end); } /* Prepare memory map for crash dump kernel */ diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c index fb095ba..3182908 100644 --- a/arch/x86/kernel/kexec-bzimage64.c +++ b/arch/x86/kernel/kexec-bzimage64.c @@ -334,7 +334,6 @@ static void *bzImage64_load(struct kimage *image, char *kernel, unsigned long setup_header_size, params_cmdline_sz; struct boot_params *params; unsigned long bootparam_load_addr, kernel_load_addr, initrd_load_addr; - unsigned long purgatory_load_addr; struct bzimage64_data *ldata; struct kexec_entry64_regs regs64; void *stack; @@ -342,6 +341,8 @@ static void *bzImage64_load(struct kimage *image, char *kernel, unsigned int efi_map_offset, efi_map_sz, efi_setup_data_offset; struct kexec_buf kbuf = { .image = image, .buf_max = ULONG_MAX, .top_down = true }; + struct kexec_buf pbuf = { .image = image, .buf_min = MIN_PURGATORY_ADDR, + .buf_max = ULONG_MAX, .top_down = true }; header = (struct setup_header *)(kernel + setup_hdr_offset); setup_sects = header->setup_sects; @@ -379,14 +380,13 @@ static void *bzImage64_load(struct kimage *image, char *kernel, * Load purgatory. For 64bit entry point, purgatory code can be * anywhere. */ - ret = kexec_load_purgatory(image, MIN_PURGATORY_ADDR, ULONG_MAX, 1, - &purgatory_load_addr); + ret = kexec_load_purgatory(image, &pbuf); if (ret) { pr_err("Loading purgatory failed\n"); return ERR_PTR(ret); } - pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr); + pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem); /* @@ -538,7 +538,7 @@ static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len) } #endif -struct kexec_file_ops kexec_bzImage64_ops = { +const struct kexec_file_ops kexec_bzImage64_ops = { .probe = bzImage64_probe, .load = bzImage64_load, .cleanup = bzImage64_cleanup, diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c index 93bd4fb..a5e55d8 100644 --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -30,8 +30,9 @@ #include <asm/set_memory.h> #ifdef CONFIG_KEXEC_FILE -static struct kexec_file_ops *kexec_file_loaders[] = { +const struct kexec_file_ops * const kexec_file_loaders[] = { &kexec_bzImage64_ops, + NULL }; #endif @@ -364,27 +365,6 @@ void arch_crash_save_vmcoreinfo(void) /* arch-dependent functionality related to kexec file-based syscall */ #ifdef CONFIG_KEXEC_FILE -int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len) -{ - int i, ret = -ENOEXEC; - struct kexec_file_ops *fops; - - for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { - fops = kexec_file_loaders[i]; - if (!fops || !fops->probe) - continue; - - ret = fops->probe(buf, buf_len); - if (!ret) { - image->fops = fops; - return ret; - } - } - - return ret; -} - void *arch_kexec_kernel_image_load(struct kimage *image) { vfree(image->arch.elf_headers); @@ -399,88 +379,53 @@ void *arch_kexec_kernel_image_load(struct kimage *image) image->cmdline_buf_len); } -int arch_kimage_file_post_load_cleanup(struct kimage *image) -{ - if (!image->fops || !image->fops->cleanup) - return 0; - - return image->fops->cleanup(image->image_loader_data); -} - -#ifdef CONFIG_KEXEC_VERIFY_SIG -int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel, - unsigned long kernel_len) -{ - if (!image->fops || !image->fops->verify_sig) { - pr_debug("kernel loader does not support signature verification."); - return -EKEYREJECTED; - } - - return image->fops->verify_sig(kernel, kernel_len); -} -#endif - /* * Apply purgatory relocations. * - * ehdr: Pointer to elf headers - * sechdrs: Pointer to section headers. - * relsec: section index of SHT_RELA section. + * @pi: Purgatory to be relocated. + * @section: Section relocations applying to. + * @relsec: Section containing RELAs. + * @symtabsec: Corresponding symtab. * * TODO: Some of the code belongs to generic code. Move that in kexec.c. */ -int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr, - Elf64_Shdr *sechdrs, unsigned int relsec) +int arch_kexec_apply_relocations_add(struct purgatory_info *pi, + Elf_Shdr *section, const Elf_Shdr *relsec, + const Elf_Shdr *symtabsec) { unsigned int i; Elf64_Rela *rel; Elf64_Sym *sym; void *location; - Elf64_Shdr *section, *symtabsec; unsigned long address, sec_base, value; const char *strtab, *name, *shstrtab; + const Elf_Shdr *sechdrs; - /* - * ->sh_offset has been modified to keep the pointer to section - * contents in memory - */ - rel = (void *)sechdrs[relsec].sh_offset; - - /* Section to which relocations apply */ - section = &sechdrs[sechdrs[relsec].sh_info]; - - pr_debug("Applying relocate section %u to %u\n", relsec, - sechdrs[relsec].sh_info); - - /* Associated symbol table */ - symtabsec = &sechdrs[sechdrs[relsec].sh_link]; - - /* String table */ - if (symtabsec->sh_link >= ehdr->e_shnum) { - /* Invalid strtab section number */ - pr_err("Invalid string table section index %d\n", - symtabsec->sh_link); - return -ENOEXEC; - } + /* String & section header string table */ + sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; + strtab = (char *)pi->ehdr + sechdrs[symtabsec->sh_link].sh_offset; + shstrtab = (char *)pi->ehdr + sechdrs[pi->ehdr->e_shstrndx].sh_offset; - strtab = (char *)sechdrs[symtabsec->sh_link].sh_offset; + rel = (void *)pi->ehdr + relsec->sh_offset; - /* section header string table */ - shstrtab = (char *)sechdrs[ehdr->e_shstrndx].sh_offset; + pr_debug("Applying relocate section %s to %u\n", + shstrtab + relsec->sh_name, relsec->sh_info); - for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + for (i = 0; i < relsec->sh_size / sizeof(*rel); i++) { /* * rel[i].r_offset contains byte offset from beginning * of section to the storage unit affected. * - * This is location to update (->sh_offset). This is temporary - * buffer where section is currently loaded. This will finally - * be loaded to a different address later, pointed to by + * This is location to update. This is temporary buffer + * where section is currently loaded. This will finally be + * loaded to a different address later, pointed to by * ->sh_addr. kexec takes care of moving it * (kexec_load_segment()). */ - location = (void *)(section->sh_offset + rel[i].r_offset); + location = pi->purgatory_buf; + location += section->sh_offset; + location += rel[i].r_offset; /* Final address of the location */ address = section->sh_addr + rel[i].r_offset; @@ -491,8 +436,8 @@ int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr, * to apply. ELF64_R_SYM() and ELF64_R_TYPE() macros get * these respectively. */ - sym = (Elf64_Sym *)symtabsec->sh_offset + - ELF64_R_SYM(rel[i].r_info); + sym = (void *)pi->ehdr + symtabsec->sh_offset; + sym += ELF64_R_SYM(rel[i].r_info); if (sym->st_name) name = strtab + sym->st_name; @@ -515,12 +460,12 @@ int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr, if (sym->st_shndx == SHN_ABS) sec_base = 0; - else if (sym->st_shndx >= ehdr->e_shnum) { + else if (sym->st_shndx >= pi->ehdr->e_shnum) { pr_err("Invalid section %d for symbol %s\n", sym->st_shndx, name); return -ENOEXEC; } else - sec_base = sechdrs[sym->st_shndx].sh_addr; + sec_base = pi->sechdrs[sym->st_shndx].sh_addr; value = sym->st_value; value += sec_base; diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile index d70c15d..2e9ee02 100644 --- a/arch/x86/purgatory/Makefile +++ b/arch/x86/purgatory/Makefile @@ -6,6 +6,9 @@ purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string targets += $(purgatory-y) PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) +$(obj)/sha256.o: $(srctree)/lib/sha256.c + $(call if_changed_rule,cc_o_c) + LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib targets += purgatory.ro diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c index 470edad..025c34a 100644 --- a/arch/x86/purgatory/purgatory.c +++ b/arch/x86/purgatory/purgatory.c @@ -11,9 +11,9 @@ */ #include <linux/bug.h> +#include <linux/sha256.h> #include <asm/purgatory.h> -#include "sha256.h" #include "../boot/string.h" unsigned long purgatory_backup_dest __section(.kexec-purgatory); diff --git a/arch/x86/purgatory/string.c b/arch/x86/purgatory/string.c index d886b1f..795ca4f 100644 --- a/arch/x86/purgatory/string.c +++ b/arch/x86/purgatory/string.c @@ -10,4 +10,16 @@ * Version 2. See the file COPYING for more details. */ +#include <linux/types.h> + #include "../boot/string.c" + +void *memcpy(void *dst, const void *src, size_t len) +{ + return __builtin_memcpy(dst, src, len); +} + +void *memset(void *dst, int c, size_t len) +{ + return __builtin_memset(dst, c, len); +} diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 04c4804..2078e70 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -15,6 +15,7 @@ #include <linux/stat.h> #include <linux/mm.h> #include <linux/module.h> +#include <linux/namei.h> #include <linux/slab.h> #include <linux/printk.h> #include <linux/mount.h> @@ -217,6 +218,26 @@ void proc_free_inum(unsigned int inum) ida_simple_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); } +static int proc_misc_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + if (flags & LOOKUP_RCU) + return -ECHILD; + + if (atomic_read(&PDE(d_inode(dentry))->in_use) < 0) + return 0; /* revalidate */ + return 1; +} + +static int proc_misc_d_delete(const struct dentry *dentry) +{ + return atomic_read(&PDE(d_inode(dentry))->in_use) < 0; +} + +static const struct dentry_operations proc_misc_dentry_ops = { + .d_revalidate = proc_misc_d_revalidate, + .d_delete = proc_misc_d_delete, +}; + /* * Don't create negative dentries here, return -ENOENT by hand * instead. @@ -234,7 +255,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, inode = proc_get_inode(dir->i_sb, de); if (!inode) return ERR_PTR(-ENOMEM); - d_set_d_op(dentry, &simple_dentry_operations); + d_set_d_op(dentry, &proc_misc_dentry_ops); d_add(dentry, inode); return NULL; } diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 0ebcbeb..9e4e638 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -99,21 +99,25 @@ struct compat_kexec_segment { #ifdef CONFIG_KEXEC_FILE struct purgatory_info { - /* Pointer to elf header of read only purgatory */ - Elf_Ehdr *ehdr; - - /* Pointer to purgatory sechdrs which are modifiable */ + /* + * Pointer to elf header at the beginning of kexec_purgatory. + * Note: kexec_purgatory is read only + */ + const Elf_Ehdr *ehdr; + /* + * Temporary, modifiable buffer for sechdrs used for relocation. + * This memory can be freed post image load. + */ Elf_Shdr *sechdrs; /* - * Temporary buffer location where purgatory is loaded and relocated - * This memory can be freed post image load + * Temporary, modifiable buffer for stripped purgatory used for + * relocation. This memory can be freed post image load. */ void *purgatory_buf; - - /* Address where purgatory is finally loaded and is executed from */ - unsigned long purgatory_load_addr; }; +struct kimage; + typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size); typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf, unsigned long kernel_len, char *initrd, @@ -135,6 +139,11 @@ struct kexec_file_ops { #endif }; +extern const struct kexec_file_ops * const kexec_file_loaders[]; + +int kexec_image_probe_default(struct kimage *image, void *buf, + unsigned long buf_len); + /** * struct kexec_buf - parameters for finding a place for a buffer in memory * @image: kexec image in which memory to search. @@ -159,10 +168,44 @@ struct kexec_buf { bool top_down; }; +int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf); +int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, + void *buf, unsigned int size, + bool get_value); +void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); + +int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi, + Elf_Shdr *section, + const Elf_Shdr *relsec, + const Elf_Shdr *symtab); +int __weak arch_kexec_apply_relocations(struct purgatory_info *pi, + Elf_Shdr *section, + const Elf_Shdr *relsec, + const Elf_Shdr *symtab); + int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(struct resource *, void *)); extern int kexec_add_buffer(struct kexec_buf *kbuf); int kexec_locate_mem_hole(struct kexec_buf *kbuf); + +/* Alignment required for elf header segment */ +#define ELF_CORE_HEADER_ALIGN 4096 + +struct crash_mem_range { + u64 start, end; +}; + +struct crash_mem { + unsigned int max_nr_ranges; + unsigned int nr_ranges; + struct crash_mem_range ranges[0]; +}; + +extern int crash_exclude_mem_range(struct crash_mem *mem, + unsigned long long mstart, + unsigned long long mend); +extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, + void **addr, unsigned long *sz); #endif /* CONFIG_KEXEC_FILE */ struct kimage { @@ -209,7 +252,7 @@ struct kimage { unsigned long cmdline_buf_len; /* File operations provided by image loader */ - struct kexec_file_ops *fops; + const struct kexec_file_ops *fops; /* Image loader handling the kernel can store a pointer here */ void *image_loader_data; @@ -226,14 +269,6 @@ extern void machine_kexec_cleanup(struct kimage *image); extern int kernel_kexec(void); extern struct page *kimage_alloc_control_pages(struct kimage *image, unsigned int order); -extern int kexec_load_purgatory(struct kimage *image, unsigned long min, - unsigned long max, int top_down, - unsigned long *load_addr); -extern int kexec_purgatory_get_set_symbol(struct kimage *image, - const char *name, void *buf, - unsigned int size, bool get_value); -extern void *kexec_purgatory_get_symbol_addr(struct kimage *image, - const char *name); extern void __crash_kexec(struct pt_regs *); extern void crash_kexec(struct pt_regs *); int kexec_should_crash(struct task_struct *); @@ -273,16 +308,6 @@ int crash_shrink_memory(unsigned long new_size); size_t crash_get_memory_size(void); void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); -int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len); -void * __weak arch_kexec_kernel_image_load(struct kimage *image); -int __weak arch_kimage_file_post_load_cleanup(struct kimage *image); -int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, - unsigned long buf_len); -int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, - Elf_Shdr *sechdrs, unsigned int relsec); -int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, - unsigned int relsec); void arch_kexec_protect_crashkres(void); void arch_kexec_unprotect_crashkres(void); diff --git a/arch/x86/purgatory/sha256.h b/include/linux/sha256.h index 2867d98..244fe01 100644 --- a/arch/x86/purgatory/sha256.h +++ b/include/linux/sha256.h @@ -13,9 +13,18 @@ #include <linux/types.h> #include <crypto/sha.h> +/* + * Stand-alone implementation of the SHA256 algorithm. It is designed to + * have as little dependencies as possible so it can be used in the + * kexec_file purgatory. In other cases you should use the implementation in + * crypto/. + * + * For details see lib/sha256.c + */ + extern int sha256_init(struct sha256_state *sctx); extern int sha256_update(struct sha256_state *sctx, const u8 *input, - unsigned int length); + unsigned int length); extern int sha256_final(struct sha256_state *sctx, u8 *hash); #endif /* SHA256_H */ @@ -225,6 +225,12 @@ static int __shm_open(struct vm_area_struct *vma) if (IS_ERR(shp)) return PTR_ERR(shp); + if (shp->shm_file != sfd->file) { + /* ID was reused */ + shm_unlock(shp); + return -EINVAL; + } + shp->shm_atim = ktime_get_real_seconds(); ipc_update_pid(&shp->shm_lprid, task_tgid(current)); shp->shm_nattch++; @@ -455,8 +461,9 @@ static int shm_mmap(struct file *file, struct vm_area_struct *vma) int ret; /* - * In case of remap_file_pages() emulation, the file can represent - * removed IPC ID: propogate shm_lock() error to caller. + * In case of remap_file_pages() emulation, the file can represent an + * IPC ID that was removed, and possibly even reused by another shm + * segment already. Propagate this case as an error to caller. */ ret = __shm_open(vma); if (ret) @@ -480,6 +487,7 @@ static int shm_release(struct inode *ino, struct file *file) struct shm_file_data *sfd = shm_file_data(file); put_ipc_ns(sfd->ns); + fput(sfd->file); shm_file_data(file) = NULL; kfree(sfd); return 0; @@ -1445,7 +1453,16 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, file->f_mapping = shp->shm_file->f_mapping; sfd->id = shp->shm_perm.id; sfd->ns = get_ipc_ns(ns); - sfd->file = shp->shm_file; + /* + * We need to take a reference to the real shm file to prevent the + * pointer from becoming stale in cases where the lifetime of the outer + * file extends beyond that of the shm segment. It's not usually + * possible, but it can happen during remap_file_pages() emulation as + * that unmaps the memory, then does ->mmap() via file reference only. + * We'll deny the ->mmap() if the shm segment was since removed, but to + * detect shm ID reuse we need to compare the file pointers. + */ + sfd->file = get_file(shp->shm_file); sfd->vm_ops = NULL; err = security_mmap_file(file, prot, flags); diff --git a/kernel/crash_core.c b/kernel/crash_core.c index a93590c..f7674d6 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -454,6 +454,7 @@ static int __init crash_save_vmcoreinfo_init(void) VMCOREINFO_NUMBER(PG_lru); VMCOREINFO_NUMBER(PG_private); VMCOREINFO_NUMBER(PG_swapcache); + VMCOREINFO_NUMBER(PG_swapbacked); VMCOREINFO_NUMBER(PG_slab); #ifdef CONFIG_MEMORY_FAILURE VMCOREINFO_NUMBER(PG_hwpoison); diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index e5bcd94..75d8e7c 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -22,50 +22,123 @@ #include <linux/ima.h> #include <crypto/hash.h> #include <crypto/sha.h> +#include <linux/elf.h> +#include <linux/elfcore.h> +#include <linux/kernel.h> +#include <linux/kexec.h> +#include <linux/slab.h> #include <linux/syscalls.h> #include <linux/vmalloc.h> #include "kexec_internal.h" static int kexec_calculate_store_digests(struct kimage *image); +/* + * Currently this is the only default function that is exported as some + * architectures need it to do additional handlings. + * In the future, other default functions may be exported too if required. + */ +int kexec_image_probe_default(struct kimage *image, void *buf, + unsigned long buf_len) +{ + const struct kexec_file_ops * const *fops; + int ret = -ENOEXEC; + + for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { + ret = (*fops)->probe(buf, buf_len); + if (!ret) { + image->fops = *fops; + return ret; + } + } + + return ret; +} + /* Architectures can provide this probe function */ int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) { - return -ENOEXEC; + return kexec_image_probe_default(image, buf, buf_len); +} + +static void *kexec_image_load_default(struct kimage *image) +{ + if (!image->fops || !image->fops->load) + return ERR_PTR(-ENOEXEC); + + return image->fops->load(image, image->kernel_buf, + image->kernel_buf_len, image->initrd_buf, + image->initrd_buf_len, image->cmdline_buf, + image->cmdline_buf_len); } void * __weak arch_kexec_kernel_image_load(struct kimage *image) { - return ERR_PTR(-ENOEXEC); + return kexec_image_load_default(image); +} + +static int kexec_image_post_load_cleanup_default(struct kimage *image) +{ + if (!image->fops || !image->fops->cleanup) + return 0; + + return image->fops->cleanup(image->image_loader_data); } int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) { - return -EINVAL; + return kexec_image_post_load_cleanup_default(image); } #ifdef CONFIG_KEXEC_VERIFY_SIG +static int kexec_image_verify_sig_default(struct kimage *image, void *buf, + unsigned long buf_len) +{ + if (!image->fops || !image->fops->verify_sig) { + pr_debug("kernel loader does not support signature verification.\n"); + return -EKEYREJECTED; + } + + return image->fops->verify_sig(buf, buf_len); +} + int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, unsigned long buf_len) { - return -EKEYREJECTED; + return kexec_image_verify_sig_default(image, buf, buf_len); } #endif -/* Apply relocations of type RELA */ +/* + * arch_kexec_apply_relocations_add - apply relocations of type RELA + * @pi: Purgatory to be relocated. + * @section: Section relocations applying to. + * @relsec: Section containing RELAs. + * @symtab: Corresponding symtab. + * + * Return: 0 on success, negative errno on error. + */ int __weak -arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, - unsigned int relsec) +arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, + const Elf_Shdr *relsec, const Elf_Shdr *symtab) { pr_err("RELA relocation unsupported.\n"); return -ENOEXEC; } -/* Apply relocations of type REL */ +/* + * arch_kexec_apply_relocations - apply relocations of type REL + * @pi: Purgatory to be relocated. + * @section: Section relocations applying to. + * @relsec: Section containing RELs. + * @symtab: Corresponding symtab. + * + * Return: 0 on success, negative errno on error. + */ int __weak -arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, - unsigned int relsec) +arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, + const Elf_Shdr *relsec, const Elf_Shdr *symtab) { pr_err("REL relocation unsupported.\n"); return -ENOEXEC; @@ -532,6 +605,9 @@ static int kexec_calculate_store_digests(struct kimage *image) struct kexec_sha_region *sha_regions; struct purgatory_info *pi = &image->purgatory_info; + if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY)) + return 0; + zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT); zero_buf_sz = PAGE_SIZE; @@ -633,87 +709,29 @@ out: return ret; } -/* Actually load purgatory. Lot of code taken from kexec-tools */ -static int __kexec_load_purgatory(struct kimage *image, unsigned long min, - unsigned long max, int top_down) +#ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY +/* + * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory. + * @pi: Purgatory to be loaded. + * @kbuf: Buffer to setup. + * + * Allocates the memory needed for the buffer. Caller is responsible to free + * the memory after use. + * + * Return: 0 on success, negative errno on error. + */ +static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi, + struct kexec_buf *kbuf) { - struct purgatory_info *pi = &image->purgatory_info; - unsigned long align, bss_align, bss_sz, bss_pad; - unsigned long entry, load_addr, curr_load_addr, bss_addr, offset; - unsigned char *buf_addr, *src; - int i, ret = 0, entry_sidx = -1; - const Elf_Shdr *sechdrs_c; - Elf_Shdr *sechdrs = NULL; - struct kexec_buf kbuf = { .image = image, .bufsz = 0, .buf_align = 1, - .buf_min = min, .buf_max = max, - .top_down = top_down }; - - /* - * sechdrs_c points to section headers in purgatory and are read - * only. No modifications allowed. - */ - sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff; - - /* - * We can not modify sechdrs_c[] and its fields. It is read only. - * Copy it over to a local copy where one can store some temporary - * data and free it at the end. We need to modify ->sh_addr and - * ->sh_offset fields to keep track of permanent and temporary - * locations of sections. - */ - sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr)); - if (!sechdrs) - return -ENOMEM; - - memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr)); - - /* - * We seem to have multiple copies of sections. First copy is which - * is embedded in kernel in read only section. Some of these sections - * will be copied to a temporary buffer and relocated. And these - * sections will finally be copied to their final destination at - * segment load time. - * - * Use ->sh_offset to reflect section address in memory. It will - * point to original read only copy if section is not allocatable. - * Otherwise it will point to temporary copy which will be relocated. - * - * Use ->sh_addr to contain final address of the section where it - * will go during execution time. - */ - for (i = 0; i < pi->ehdr->e_shnum; i++) { - if (sechdrs[i].sh_type == SHT_NOBITS) - continue; - - sechdrs[i].sh_offset = (unsigned long)pi->ehdr + - sechdrs[i].sh_offset; - } - - /* - * Identify entry point section and make entry relative to section - * start. - */ - entry = pi->ehdr->e_entry; - for (i = 0; i < pi->ehdr->e_shnum; i++) { - if (!(sechdrs[i].sh_flags & SHF_ALLOC)) - continue; - - if (!(sechdrs[i].sh_flags & SHF_EXECINSTR)) - continue; - - /* Make entry section relative */ - if (sechdrs[i].sh_addr <= pi->ehdr->e_entry && - ((sechdrs[i].sh_addr + sechdrs[i].sh_size) > - pi->ehdr->e_entry)) { - entry_sidx = i; - entry -= sechdrs[i].sh_addr; - break; - } - } + const Elf_Shdr *sechdrs; + unsigned long bss_align; + unsigned long bss_sz; + unsigned long align; + int i, ret; - /* Determine how much memory is needed to load relocatable object. */ - bss_align = 1; - bss_sz = 0; + sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; + kbuf->buf_align = bss_align = 1; + kbuf->bufsz = bss_sz = 0; for (i = 0; i < pi->ehdr->e_shnum; i++) { if (!(sechdrs[i].sh_flags & SHF_ALLOC)) @@ -721,111 +739,124 @@ static int __kexec_load_purgatory(struct kimage *image, unsigned long min, align = sechdrs[i].sh_addralign; if (sechdrs[i].sh_type != SHT_NOBITS) { - if (kbuf.buf_align < align) - kbuf.buf_align = align; - kbuf.bufsz = ALIGN(kbuf.bufsz, align); - kbuf.bufsz += sechdrs[i].sh_size; + if (kbuf->buf_align < align) + kbuf->buf_align = align; + kbuf->bufsz = ALIGN(kbuf->bufsz, align); + kbuf->bufsz += sechdrs[i].sh_size; } else { - /* bss section */ if (bss_align < align) bss_align = align; bss_sz = ALIGN(bss_sz, align); bss_sz += sechdrs[i].sh_size; } } + kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align); + kbuf->memsz = kbuf->bufsz + bss_sz; + if (kbuf->buf_align < bss_align) + kbuf->buf_align = bss_align; - /* Determine the bss padding required to align bss properly */ - bss_pad = 0; - if (kbuf.bufsz & (bss_align - 1)) - bss_pad = bss_align - (kbuf.bufsz & (bss_align - 1)); - - kbuf.memsz = kbuf.bufsz + bss_pad + bss_sz; + kbuf->buffer = vzalloc(kbuf->bufsz); + if (!kbuf->buffer) + return -ENOMEM; + pi->purgatory_buf = kbuf->buffer; - /* Allocate buffer for purgatory */ - kbuf.buffer = vzalloc(kbuf.bufsz); - if (!kbuf.buffer) { - ret = -ENOMEM; + ret = kexec_add_buffer(kbuf); + if (ret) goto out; - } - if (kbuf.buf_align < bss_align) - kbuf.buf_align = bss_align; + return 0; +out: + vfree(pi->purgatory_buf); + pi->purgatory_buf = NULL; + return ret; +} - /* Add buffer to segment list */ - ret = kexec_add_buffer(&kbuf); - if (ret) - goto out; - pi->purgatory_load_addr = kbuf.mem; +/* + * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer. + * @pi: Purgatory to be loaded. + * @kbuf: Buffer prepared to store purgatory. + * + * Allocates the memory needed for the buffer. Caller is responsible to free + * the memory after use. + * + * Return: 0 on success, negative errno on error. + */ +static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, + struct kexec_buf *kbuf) +{ + unsigned long bss_addr; + unsigned long offset; + Elf_Shdr *sechdrs; + int i; + + /* + * The section headers in kexec_purgatory are read-only. In order to + * have them modifiable make a temporary copy. + */ + sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr)); + if (!sechdrs) + return -ENOMEM; + memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, + pi->ehdr->e_shnum * sizeof(Elf_Shdr)); + pi->sechdrs = sechdrs; - /* Load SHF_ALLOC sections */ - buf_addr = kbuf.buffer; - load_addr = curr_load_addr = pi->purgatory_load_addr; - bss_addr = load_addr + kbuf.bufsz + bss_pad; + offset = 0; + bss_addr = kbuf->mem + kbuf->bufsz; + kbuf->image->start = pi->ehdr->e_entry; for (i = 0; i < pi->ehdr->e_shnum; i++) { + unsigned long align; + void *src, *dst; + if (!(sechdrs[i].sh_flags & SHF_ALLOC)) continue; align = sechdrs[i].sh_addralign; - if (sechdrs[i].sh_type != SHT_NOBITS) { - curr_load_addr = ALIGN(curr_load_addr, align); - offset = curr_load_addr - load_addr; - /* We already modifed ->sh_offset to keep src addr */ - src = (char *) sechdrs[i].sh_offset; - memcpy(buf_addr + offset, src, sechdrs[i].sh_size); - - /* Store load address and source address of section */ - sechdrs[i].sh_addr = curr_load_addr; - - /* - * This section got copied to temporary buffer. Update - * ->sh_offset accordingly. - */ - sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset); - - /* Advance to the next address */ - curr_load_addr += sechdrs[i].sh_size; - } else { + if (sechdrs[i].sh_type == SHT_NOBITS) { bss_addr = ALIGN(bss_addr, align); sechdrs[i].sh_addr = bss_addr; bss_addr += sechdrs[i].sh_size; + continue; } - } - /* Update entry point based on load address of text section */ - if (entry_sidx >= 0) - entry += sechdrs[entry_sidx].sh_addr; + offset = ALIGN(offset, align); + if (sechdrs[i].sh_flags & SHF_EXECINSTR && + pi->ehdr->e_entry >= sechdrs[i].sh_addr && + pi->ehdr->e_entry < (sechdrs[i].sh_addr + + sechdrs[i].sh_size)) { + kbuf->image->start -= sechdrs[i].sh_addr; + kbuf->image->start += kbuf->mem + offset; + } - /* Make kernel jump to purgatory after shutdown */ - image->start = entry; + src = (void *)pi->ehdr + sechdrs[i].sh_offset; + dst = pi->purgatory_buf + offset; + memcpy(dst, src, sechdrs[i].sh_size); - /* Used later to get/set symbol values */ - pi->sechdrs = sechdrs; + sechdrs[i].sh_addr = kbuf->mem + offset; + sechdrs[i].sh_offset = offset; + offset += sechdrs[i].sh_size; + } - /* - * Used later to identify which section is purgatory and skip it - * from checksumming. - */ - pi->purgatory_buf = kbuf.buffer; - return ret; -out: - vfree(sechdrs); - vfree(kbuf.buffer); - return ret; + return 0; } static int kexec_apply_relocations(struct kimage *image) { int i, ret; struct purgatory_info *pi = &image->purgatory_info; - Elf_Shdr *sechdrs = pi->sechdrs; + const Elf_Shdr *sechdrs; + + sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; - /* Apply relocations */ for (i = 0; i < pi->ehdr->e_shnum; i++) { - Elf_Shdr *section, *symtab; + const Elf_Shdr *relsec; + const Elf_Shdr *symtab; + Elf_Shdr *section; + + relsec = sechdrs + i; - if (sechdrs[i].sh_type != SHT_RELA && - sechdrs[i].sh_type != SHT_REL) + if (relsec->sh_type != SHT_RELA && + relsec->sh_type != SHT_REL) continue; /* @@ -834,12 +865,12 @@ static int kexec_apply_relocations(struct kimage *image) * symbol table. And ->sh_info contains section header * index of section to which relocations apply. */ - if (sechdrs[i].sh_info >= pi->ehdr->e_shnum || - sechdrs[i].sh_link >= pi->ehdr->e_shnum) + if (relsec->sh_info >= pi->ehdr->e_shnum || + relsec->sh_link >= pi->ehdr->e_shnum) return -ENOEXEC; - section = &sechdrs[sechdrs[i].sh_info]; - symtab = &sechdrs[sechdrs[i].sh_link]; + section = pi->sechdrs + relsec->sh_info; + symtab = sechdrs + relsec->sh_link; if (!(section->sh_flags & SHF_ALLOC)) continue; @@ -856,12 +887,12 @@ static int kexec_apply_relocations(struct kimage *image) * Respective architecture needs to provide support for applying * relocations of type SHT_RELA/SHT_REL. */ - if (sechdrs[i].sh_type == SHT_RELA) - ret = arch_kexec_apply_relocations_add(pi->ehdr, - sechdrs, i); - else if (sechdrs[i].sh_type == SHT_REL) - ret = arch_kexec_apply_relocations(pi->ehdr, - sechdrs, i); + if (relsec->sh_type == SHT_RELA) + ret = arch_kexec_apply_relocations_add(pi, section, + relsec, symtab); + else if (relsec->sh_type == SHT_REL) + ret = arch_kexec_apply_relocations(pi, section, + relsec, symtab); if (ret) return ret; } @@ -869,10 +900,18 @@ static int kexec_apply_relocations(struct kimage *image) return 0; } -/* Load relocatable purgatory object and relocate it appropriately */ -int kexec_load_purgatory(struct kimage *image, unsigned long min, - unsigned long max, int top_down, - unsigned long *load_addr) +/* + * kexec_load_purgatory - Load and relocate the purgatory object. + * @image: Image to add the purgatory to. + * @kbuf: Memory parameters to use. + * + * Allocates the memory needed for image->purgatory_info.sechdrs and + * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible + * to free the memory after use. + * + * Return: 0 on success, negative errno on error. + */ +int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf) { struct purgatory_info *pi = &image->purgatory_info; int ret; @@ -880,55 +919,51 @@ int kexec_load_purgatory(struct kimage *image, unsigned long min, if (kexec_purgatory_size <= 0) return -EINVAL; - if (kexec_purgatory_size < sizeof(Elf_Ehdr)) - return -ENOEXEC; - - pi->ehdr = (Elf_Ehdr *)kexec_purgatory; - - if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0 - || pi->ehdr->e_type != ET_REL - || !elf_check_arch(pi->ehdr) - || pi->ehdr->e_shentsize != sizeof(Elf_Shdr)) - return -ENOEXEC; - - if (pi->ehdr->e_shoff >= kexec_purgatory_size - || (pi->ehdr->e_shnum * sizeof(Elf_Shdr) > - kexec_purgatory_size - pi->ehdr->e_shoff)) - return -ENOEXEC; + pi->ehdr = (const Elf_Ehdr *)kexec_purgatory; - ret = __kexec_load_purgatory(image, min, max, top_down); + ret = kexec_purgatory_setup_kbuf(pi, kbuf); if (ret) return ret; + ret = kexec_purgatory_setup_sechdrs(pi, kbuf); + if (ret) + goto out_free_kbuf; + ret = kexec_apply_relocations(image); if (ret) goto out; - *load_addr = pi->purgatory_load_addr; return 0; out: vfree(pi->sechdrs); pi->sechdrs = NULL; - +out_free_kbuf: vfree(pi->purgatory_buf); pi->purgatory_buf = NULL; return ret; } -static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, - const char *name) +/* + * kexec_purgatory_find_symbol - find a symbol in the purgatory + * @pi: Purgatory to search in. + * @name: Name of the symbol. + * + * Return: pointer to symbol in read-only symtab on success, NULL on error. + */ +static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, + const char *name) { - Elf_Sym *syms; - Elf_Shdr *sechdrs; - Elf_Ehdr *ehdr; - int i, k; + const Elf_Shdr *sechdrs; + const Elf_Ehdr *ehdr; + const Elf_Sym *syms; const char *strtab; + int i, k; - if (!pi->sechdrs || !pi->ehdr) + if (!pi->ehdr) return NULL; - sechdrs = pi->sechdrs; ehdr = pi->ehdr; + sechdrs = (void *)ehdr + ehdr->e_shoff; for (i = 0; i < ehdr->e_shnum; i++) { if (sechdrs[i].sh_type != SHT_SYMTAB) @@ -937,8 +972,8 @@ static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, if (sechdrs[i].sh_link >= ehdr->e_shnum) /* Invalid strtab section number */ continue; - strtab = (char *)sechdrs[sechdrs[i].sh_link].sh_offset; - syms = (Elf_Sym *)sechdrs[i].sh_offset; + strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset; + syms = (void *)ehdr + sechdrs[i].sh_offset; /* Go through symbols for a match */ for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) { @@ -966,7 +1001,7 @@ static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name) { struct purgatory_info *pi = &image->purgatory_info; - Elf_Sym *sym; + const Elf_Sym *sym; Elf_Shdr *sechdr; sym = kexec_purgatory_find_symbol(pi, name); @@ -989,9 +1024,9 @@ void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name) int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, void *buf, unsigned int size, bool get_value) { - Elf_Sym *sym; - Elf_Shdr *sechdrs; struct purgatory_info *pi = &image->purgatory_info; + const Elf_Sym *sym; + Elf_Shdr *sec; char *sym_buf; sym = kexec_purgatory_find_symbol(pi, name); @@ -1004,16 +1039,15 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, return -EINVAL; } - sechdrs = pi->sechdrs; + sec = pi->sechdrs + sym->st_shndx; - if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) { + if (sec->sh_type == SHT_NOBITS) { pr_err("symbol %s is in a bss section. Cannot %s\n", name, get_value ? "get" : "set"); return -EINVAL; } - sym_buf = (unsigned char *)sechdrs[sym->st_shndx].sh_offset + - sym->st_value; + sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value; if (get_value) memcpy((void *)buf, sym_buf, size); @@ -1022,3 +1056,174 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, return 0; } +#endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */ + +int crash_exclude_mem_range(struct crash_mem *mem, + unsigned long long mstart, unsigned long long mend) +{ + int i, j; + unsigned long long start, end; + struct crash_mem_range temp_range = {0, 0}; + + for (i = 0; i < mem->nr_ranges; i++) { + start = mem->ranges[i].start; + end = mem->ranges[i].end; + + if (mstart > end || mend < start) + continue; + + /* Truncate any area outside of range */ + if (mstart < start) + mstart = start; + if (mend > end) + mend = end; + + /* Found completely overlapping range */ + if (mstart == start && mend == end) { + mem->ranges[i].start = 0; + mem->ranges[i].end = 0; + if (i < mem->nr_ranges - 1) { + /* Shift rest of the ranges to left */ + for (j = i; j < mem->nr_ranges - 1; j++) { + mem->ranges[j].start = + mem->ranges[j+1].start; + mem->ranges[j].end = + mem->ranges[j+1].end; + } + } + mem->nr_ranges--; + return 0; + } + + if (mstart > start && mend < end) { + /* Split original range */ + mem->ranges[i].end = mstart - 1; + temp_range.start = mend + 1; + temp_range.end = end; + } else if (mstart != start) + mem->ranges[i].end = mstart - 1; + else + mem->ranges[i].start = mend + 1; + break; + } + + /* If a split happened, add the split to array */ + if (!temp_range.end) + return 0; + + /* Split happened */ + if (i == mem->max_nr_ranges - 1) + return -ENOMEM; + + /* Location where new range should go */ + j = i + 1; + if (j < mem->nr_ranges) { + /* Move over all ranges one slot towards the end */ + for (i = mem->nr_ranges - 1; i >= j; i--) + mem->ranges[i + 1] = mem->ranges[i]; + } + + mem->ranges[j].start = temp_range.start; + mem->ranges[j].end = temp_range.end; + mem->nr_ranges++; + return 0; +} + +int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, + void **addr, unsigned long *sz) +{ + Elf64_Ehdr *ehdr; + Elf64_Phdr *phdr; + unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; + unsigned char *buf; + unsigned int cpu, i; + unsigned long long notes_addr; + unsigned long mstart, mend; + + /* extra phdr for vmcoreinfo elf note */ + nr_phdr = nr_cpus + 1; + nr_phdr += mem->nr_ranges; + + /* + * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping + * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64). + * I think this is required by tools like gdb. So same physical + * memory will be mapped in two elf headers. One will contain kernel + * text virtual addresses and other will have __va(physical) addresses. + */ + + nr_phdr++; + elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr); + elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN); + + buf = vzalloc(elf_sz); + if (!buf) + return -ENOMEM; + + ehdr = (Elf64_Ehdr *)buf; + phdr = (Elf64_Phdr *)(ehdr + 1); + memcpy(ehdr->e_ident, ELFMAG, SELFMAG); + ehdr->e_ident[EI_CLASS] = ELFCLASS64; + ehdr->e_ident[EI_DATA] = ELFDATA2LSB; + ehdr->e_ident[EI_VERSION] = EV_CURRENT; + ehdr->e_ident[EI_OSABI] = ELF_OSABI; + memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); + ehdr->e_type = ET_CORE; + ehdr->e_machine = ELF_ARCH; + ehdr->e_version = EV_CURRENT; + ehdr->e_phoff = sizeof(Elf64_Ehdr); + ehdr->e_ehsize = sizeof(Elf64_Ehdr); + ehdr->e_phentsize = sizeof(Elf64_Phdr); + + /* Prepare one phdr of type PT_NOTE for each present cpu */ + for_each_present_cpu(cpu) { + phdr->p_type = PT_NOTE; + notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu)); + phdr->p_offset = phdr->p_paddr = notes_addr; + phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t); + (ehdr->e_phnum)++; + phdr++; + } + + /* Prepare one PT_NOTE header for vmcoreinfo */ + phdr->p_type = PT_NOTE; + phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note(); + phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; + (ehdr->e_phnum)++; + phdr++; + + /* Prepare PT_LOAD type program header for kernel text region */ + if (kernel_map) { + phdr->p_type = PT_LOAD; + phdr->p_flags = PF_R|PF_W|PF_X; + phdr->p_vaddr = (Elf64_Addr)_text; + phdr->p_filesz = phdr->p_memsz = _end - _text; + phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); + ehdr->e_phnum++; + phdr++; + } + + /* Go through all the ranges in mem->ranges[] and prepare phdr */ + for (i = 0; i < mem->nr_ranges; i++) { + mstart = mem->ranges[i].start; + mend = mem->ranges[i].end; + + phdr->p_type = PT_LOAD; + phdr->p_flags = PF_R|PF_W|PF_X; + phdr->p_offset = mstart; + + phdr->p_paddr = mstart; + phdr->p_vaddr = (unsigned long long) __va(mstart); + phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; + phdr->p_align = 0; + ehdr->e_phnum++; + phdr++; + pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n", + phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, + ehdr->e_phnum, phdr->p_offset); + } + + *addr = buf; + *sz = elf_sz; + return 0; +} diff --git a/kernel/resource.c b/kernel/resource.c index e270b50..2af6c03 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -651,7 +651,8 @@ static int __find_resource(struct resource *root, struct resource *old, alloc.start = constraint->alignf(constraint->alignf_data, &avail, size, constraint->align); alloc.end = alloc.start + size - 1; - if (resource_contains(&avail, &alloc)) { + if (alloc.start <= alloc.end && + resource_contains(&avail, &alloc)) { new->start = alloc.start; new->end = alloc.end; return 0; diff --git a/arch/x86/purgatory/sha256.c b/lib/sha256.c index 548ca67..4400c83 100644 --- a/arch/x86/purgatory/sha256.c +++ b/lib/sha256.c @@ -16,9 +16,9 @@ */ #include <linux/bitops.h> +#include <linux/sha256.h> +#include <linux/string.h> #include <asm/byteorder.h> -#include "sha256.h" -#include "../boot/string.h" static inline u32 Ch(u32 x, u32 y, u32 z) { diff --git a/mm/filemap.c b/mm/filemap.c index ab77e19..9276bdb2 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2719,7 +2719,6 @@ out: sb_end_pagefault(inode->i_sb); return ret; } -EXPORT_SYMBOL(filemap_page_mkwrite); const struct vm_operations_struct generic_file_vm_ops = { .fault = filemap_fault, @@ -2750,6 +2749,10 @@ int generic_file_readonly_mmap(struct file *file, struct vm_area_struct *vma) return generic_file_mmap(file, vma); } #else +int filemap_page_mkwrite(struct vm_fault *vmf) +{ + return -ENOSYS; +} int generic_file_mmap(struct file * file, struct vm_area_struct * vma) { return -ENOSYS; @@ -2760,6 +2763,7 @@ int generic_file_readonly_mmap(struct file * file, struct vm_area_struct * vma) } #endif /* CONFIG_MMU */ +EXPORT_SYMBOL(filemap_page_mkwrite); EXPORT_SYMBOL(generic_file_mmap); EXPORT_SYMBOL(generic_file_readonly_mmap); @@ -1740,7 +1740,9 @@ bool gup_fast_permitted(unsigned long start, int nr_pages, int write) /* * Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to - * the regular GUP. It will only return non-negative values. + * the regular GUP. + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) @@ -1806,9 +1808,12 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write, len = (unsigned long) nr_pages << PAGE_SHIFT; end = start + len; + if (nr_pages <= 0) + return 0; + if (unlikely(!access_ok(write ? VERIFY_WRITE : VERIFY_READ, (void __user *)start, len))) - return 0; + return -EFAULT; if (gup_fast_permitted(start, nr_pages, write)) { local_irq_disable(); diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c index 5c8e2ab..0f44759 100644 --- a/mm/gup_benchmark.c +++ b/mm/gup_benchmark.c @@ -23,7 +23,7 @@ static int __gup_benchmark_ioctl(unsigned int cmd, struct page **pages; nr_pages = gup->size / PAGE_SIZE; - pages = kvmalloc(sizeof(void *) * nr_pages, GFP_KERNEL); + pages = kvzalloc(sizeof(void *) * nr_pages, GFP_KERNEL); if (!pages) return -ENOMEM; @@ -41,6 +41,8 @@ static int __gup_benchmark_ioctl(unsigned int cmd, } nr = get_user_pages_fast(addr, nr, gup->flags & 1, pages + i); + if (nr <= 0) + break; i += nr; } end_time = ktime_get(); @@ -4086,7 +4086,8 @@ next: next_reap_node(); out: /* Set up the next iteration */ - schedule_delayed_work(work, round_jiffies_relative(REAPTIMEOUT_AC)); + schedule_delayed_work_on(smp_processor_id(), work, + round_jiffies_relative(REAPTIMEOUT_AC)); } void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo) @@ -297,8 +297,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) /* * Like get_user_pages_fast() except its IRQ-safe in that it won't fall * back to the regular GUP. - * If the architecture not support this function, simply return with no - * page pinned + * Note a difference with get_user_pages_fast: this always returns the + * number of pages pinned, 0 if no pages were pinned. + * If the architecture does not support this function, simply return with no + * pages pinned. */ int __weak __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) |
