diff options
Diffstat (limited to 'arch/x86/boot')
| -rw-r--r-- | arch/x86/boot/Makefile | 5 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/cmdline.c | 2 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/eboot.c | 73 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/head_64.S | 86 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/kaslr.c | 191 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/misc.c | 5 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/pagetable.c | 18 | ||||
| -rw-r--r-- | arch/x86/boot/copy.S | 20 | ||||
| -rw-r--r-- | arch/x86/boot/string.c | 8 | ||||
| -rw-r--r-- | arch/x86/boot/string.h | 1 |
10 files changed, 292 insertions, 117 deletions
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index 0d810fb..d88a2fd 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -73,12 +73,13 @@ UBSAN_SANITIZE := n $(obj)/bzImage: asflags-y := $(SVGA_MODE) quiet_cmd_image = BUILD $@ +silent_redirect_image = >/dev/null cmd_image = $(obj)/tools/build $(obj)/setup.bin $(obj)/vmlinux.bin \ - $(obj)/zoffset.h $@ + $(obj)/zoffset.h $@ $($(quiet)redirect_image) $(obj)/bzImage: $(obj)/setup.bin $(obj)/vmlinux.bin $(obj)/tools/build FORCE $(call if_changed,image) - @echo 'Kernel: $@ is ready' ' (#'`cat .version`')' + @$(kecho) 'Kernel: $@ is ready' ' (#'`cat .version`')' OBJCOPYFLAGS_vmlinux.bin := -O binary -R .note -R .comment -S $(obj)/vmlinux.bin: $(obj)/compressed/vmlinux FORCE diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c index 73ccf63..9dc1ce6 100644 --- a/arch/x86/boot/compressed/cmdline.c +++ b/arch/x86/boot/compressed/cmdline.c @@ -13,7 +13,7 @@ static inline char rdfs8(addr_t addr) return *((char *)(fs + addr)); } #include "../cmdline.c" -static unsigned long get_cmd_line_ptr(void) +unsigned long get_cmd_line_ptr(void) { unsigned long cmd_line_ptr = boot_params->hdr.cmd_line_ptr; diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index cbf4b87..c3e869e 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1046,9 +1046,31 @@ struct boot_params *efi_main(struct efi_config *c, memset((char *)gdt->address, 0x0, gdt->size); desc = (struct desc_struct *)gdt->address; - /* The first GDT is a dummy and the second is unused. */ - desc += 2; + /* The first GDT is a dummy. */ + desc++; + + if (IS_ENABLED(CONFIG_X86_64)) { + /* __KERNEL32_CS */ + desc->limit0 = 0xffff; + desc->base0 = 0x0000; + desc->base1 = 0x0000; + desc->type = SEG_TYPE_CODE | SEG_TYPE_EXEC_READ; + desc->s = DESC_TYPE_CODE_DATA; + desc->dpl = 0; + desc->p = 1; + desc->limit = 0xf; + desc->avl = 0; + desc->l = 0; + desc->d = SEG_OP_SIZE_32BIT; + desc->g = SEG_GRANULARITY_4KB; + desc->base2 = 0x00; + desc++; + } else { + /* Second entry is unused on 32-bit */ + desc++; + } + /* __KERNEL_CS */ desc->limit0 = 0xffff; desc->base0 = 0x0000; desc->base1 = 0x0000; @@ -1058,12 +1080,18 @@ struct boot_params *efi_main(struct efi_config *c, desc->p = 1; desc->limit = 0xf; desc->avl = 0; - desc->l = 0; - desc->d = SEG_OP_SIZE_32BIT; + if (IS_ENABLED(CONFIG_X86_64)) { + desc->l = 1; + desc->d = 0; + } else { + desc->l = 0; + desc->d = SEG_OP_SIZE_32BIT; + } desc->g = SEG_GRANULARITY_4KB; desc->base2 = 0x00; - desc++; + + /* __KERNEL_DS */ desc->limit0 = 0xffff; desc->base0 = 0x0000; desc->base1 = 0x0000; @@ -1077,24 +1105,25 @@ struct boot_params *efi_main(struct efi_config *c, desc->d = SEG_OP_SIZE_32BIT; desc->g = SEG_GRANULARITY_4KB; desc->base2 = 0x00; - -#ifdef CONFIG_X86_64 - /* Task segment value */ desc++; - desc->limit0 = 0x0000; - desc->base0 = 0x0000; - desc->base1 = 0x0000; - desc->type = SEG_TYPE_TSS; - desc->s = 0; - desc->dpl = 0; - desc->p = 1; - desc->limit = 0x0; - desc->avl = 0; - desc->l = 0; - desc->d = 0; - desc->g = SEG_GRANULARITY_4KB; - desc->base2 = 0x00; -#endif /* CONFIG_X86_64 */ + + if (IS_ENABLED(CONFIG_X86_64)) { + /* Task segment value */ + desc->limit0 = 0x0000; + desc->base0 = 0x0000; + desc->base1 = 0x0000; + desc->type = SEG_TYPE_TSS; + desc->s = 0; + desc->dpl = 0; + desc->p = 1; + desc->limit = 0x0; + desc->avl = 0; + desc->l = 0; + desc->d = 0; + desc->g = SEG_GRANULARITY_4KB; + desc->base2 = 0x00; + desc++; + } asm volatile("cli"); asm volatile ("lgdt %0" : : "m" (*gdt)); diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index d2ae1f8..fbf4c32 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -346,6 +346,48 @@ preferred_addr: /* Set up the stack */ leaq boot_stack_end(%rbx), %rsp +#ifdef CONFIG_X86_5LEVEL + /* Check if 5-level paging has already enabled */ + movq %cr4, %rax + testl $X86_CR4_LA57, %eax + jnz lvl5 + + /* + * At this point we are in long mode with 4-level paging enabled, + * but we want to enable 5-level paging. + * + * The problem is that we cannot do it directly. Setting LA57 in + * long mode would trigger #GP. So we need to switch off long mode + * first. + * + * NOTE: This is not going to work if bootloader put us above 4G + * limit. + * + * The first step is go into compatibility mode. + */ + + /* Clear additional page table */ + leaq lvl5_pgtable(%rbx), %rdi + xorq %rax, %rax + movq $(PAGE_SIZE/8), %rcx + rep stosq + + /* + * Setup current CR3 as the first and only entry in a new top level + * page table. + */ + movq %cr3, %rdi + leaq 0x7 (%rdi), %rax + movq %rax, lvl5_pgtable(%rbx) + + /* Switch to compatibility mode (CS.L = 0 CS.D = 1) via far return */ + pushq $__KERNEL32_CS + leaq compatible_mode(%rip), %rax + pushq %rax + lretq +lvl5: +#endif + /* Zero EFLAGS */ pushq $0 popfq @@ -429,6 +471,44 @@ relocated: jmp *%rax .code32 +#ifdef CONFIG_X86_5LEVEL +compatible_mode: + /* Setup data and stack segments */ + movl $__KERNEL_DS, %eax + movl %eax, %ds + movl %eax, %ss + + /* Disable paging */ + movl %cr0, %eax + btrl $X86_CR0_PG_BIT, %eax + movl %eax, %cr0 + + /* Point CR3 to 5-level paging */ + leal lvl5_pgtable(%ebx), %eax + movl %eax, %cr3 + + /* Enable PAE and LA57 mode */ + movl %cr4, %eax + orl $(X86_CR4_PAE | X86_CR4_LA57), %eax + movl %eax, %cr4 + + /* Calculate address we are running at */ + call 1f +1: popl %edi + subl $1b, %edi + + /* Prepare stack for far return to Long Mode */ + pushl $__KERNEL_CS + leal lvl5(%edi), %eax + push %eax + + /* Enable paging back */ + movl $(X86_CR0_PG | X86_CR0_PE), %eax + movl %eax, %cr0 + + lret +#endif + no_longmode: /* This isn't an x86-64 CPU so hang */ 1: @@ -442,7 +522,7 @@ gdt: .word gdt_end - gdt .long gdt .word 0 - .quad 0x0000000000000000 /* NULL descriptor */ + .quad 0x00cf9a000000ffff /* __KERNEL32_CS */ .quad 0x00af9a000000ffff /* __KERNEL_CS */ .quad 0x00cf92000000ffff /* __KERNEL_DS */ .quad 0x0080890000000000 /* TS descriptor */ @@ -486,3 +566,7 @@ boot_stack_end: .balign 4096 pgtable: .fill BOOT_PGT_SIZE, 1, 0 +#ifdef CONFIG_X86_5LEVEL +lvl5_pgtable: + .fill PAGE_SIZE, 1, 0 +#endif diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 56a7e92..91f27ab 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -9,16 +9,42 @@ * contain the entire properly aligned running kernel image. * */ + +/* + * isspace() in linux/ctype.h is expected by next_args() to filter + * out "space/lf/tab". While boot/ctype.h conflicts with linux/ctype.h, + * since isdigit() is implemented in both of them. Hence disable it + * here. + */ +#define BOOT_CTYPE_H + +/* + * _ctype[] in lib/ctype.c is needed by isspace() of linux/ctype.h. + * While both lib/ctype.c and lib/cmdline.c will bring EXPORT_SYMBOL + * which is meaningless and will cause compiling error in some cases. + * So do not include linux/export.h and define EXPORT_SYMBOL(sym) + * as empty. + */ +#define _LINUX_EXPORT_H +#define EXPORT_SYMBOL(sym) + #include "misc.h" #include "error.h" -#include "../boot.h" +#include "../string.h" #include <generated/compile.h> #include <linux/module.h> #include <linux/uts.h> #include <linux/utsname.h> +#include <linux/ctype.h> #include <generated/utsrelease.h> +/* Macros used by the included decompressor code below. */ +#define STATIC +#include <linux/decompress/mm.h> + +extern unsigned long get_cmd_line_ptr(void); + /* Simplified build-specific string for starting entropy. */ static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION; @@ -62,6 +88,11 @@ struct mem_vector { static bool memmap_too_large; + +/* Store memory limit specified by "mem=nn[KMG]" or "memmap=nn[KMG]" */ +unsigned long long mem_limit = ULLONG_MAX; + + enum mem_avoid_index { MEM_AVOID_ZO_RANGE = 0, MEM_AVOID_INITRD, @@ -85,49 +116,14 @@ static bool mem_overlaps(struct mem_vector *one, struct mem_vector *two) return true; } -/** - * _memparse - Parse a string with mem suffixes into a number - * @ptr: Where parse begins - * @retptr: (output) Optional pointer to next char after parse completes - * - * Parses a string into a number. The number stored at @ptr is - * potentially suffixed with K, M, G, T, P, E. - */ -static unsigned long long _memparse(const char *ptr, char **retptr) +char *skip_spaces(const char *str) { - char *endptr; /* Local pointer to end of parsed string */ - - unsigned long long ret = simple_strtoull(ptr, &endptr, 0); - - switch (*endptr) { - case 'E': - case 'e': - ret <<= 10; - case 'P': - case 'p': - ret <<= 10; - case 'T': - case 't': - ret <<= 10; - case 'G': - case 'g': - ret <<= 10; - case 'M': - case 'm': - ret <<= 10; - case 'K': - case 'k': - ret <<= 10; - endptr++; - default: - break; - } - - if (retptr) - *retptr = endptr; - - return ret; + while (isspace(*str)) + ++str; + return (char *)str; } +#include "../../../../lib/ctype.c" +#include "../../../../lib/cmdline.c" static int parse_memmap(char *p, unsigned long long *start, unsigned long long *size) @@ -142,40 +138,41 @@ parse_memmap(char *p, unsigned long long *start, unsigned long long *size) return -EINVAL; oldp = p; - *size = _memparse(p, &p); + *size = memparse(p, &p); if (p == oldp) return -EINVAL; switch (*p) { - case '@': - /* Skip this region, usable */ - *start = 0; - *size = 0; - return 0; case '#': case '$': case '!': - *start = _memparse(p + 1, &p); + *start = memparse(p + 1, &p); + return 0; + case '@': + /* memmap=nn@ss specifies usable region, should be skipped */ + *size = 0; + /* Fall through */ + default: + /* + * If w/o offset, only size specified, memmap=nn[KMG] has the + * same behaviour as mem=nn[KMG]. It limits the max address + * system can use. Region above the limit should be avoided. + */ + *start = 0; return 0; } return -EINVAL; } -static void mem_avoid_memmap(void) +static void mem_avoid_memmap(char *str) { - char arg[128]; + static int i; int rc; - int i; - char *str; - /* See if we have any memmap areas */ - rc = cmdline_find_option("memmap", arg, sizeof(arg)); - if (rc <= 0) + if (i >= MAX_MEMMAP_REGIONS) return; - i = 0; - str = arg; while (str && (i < MAX_MEMMAP_REGIONS)) { int rc; unsigned long long start, size; @@ -188,9 +185,14 @@ static void mem_avoid_memmap(void) if (rc < 0) break; str = k; - /* A usable region that should not be skipped */ - if (size == 0) + + if (start == 0) { + /* Store the specified memory limit if size > 0 */ + if (size > 0) + mem_limit = size; + continue; + } mem_avoid[MEM_AVOID_MEMMAP_BEGIN + i].start = start; mem_avoid[MEM_AVOID_MEMMAP_BEGIN + i].size = size; @@ -202,6 +204,57 @@ static void mem_avoid_memmap(void) memmap_too_large = true; } +static int handle_mem_memmap(void) +{ + char *args = (char *)get_cmd_line_ptr(); + size_t len = strlen((char *)args); + char *tmp_cmdline; + char *param, *val; + u64 mem_size; + + if (!strstr(args, "memmap=") && !strstr(args, "mem=")) + return 0; + + tmp_cmdline = malloc(len + 1); + if (!tmp_cmdline ) + error("Failed to allocate space for tmp_cmdline"); + + memcpy(tmp_cmdline, args, len); + tmp_cmdline[len] = 0; + args = tmp_cmdline; + + /* Chew leading spaces */ + args = skip_spaces(args); + + while (*args) { + args = next_arg(args, ¶m, &val); + /* Stop at -- */ + if (!val && strcmp(param, "--") == 0) { + warn("Only '--' specified in cmdline"); + free(tmp_cmdline); + return -1; + } + + if (!strcmp(param, "memmap")) { + mem_avoid_memmap(val); + } else if (!strcmp(param, "mem")) { + char *p = val; + + if (!strcmp(p, "nopentium")) + continue; + mem_size = memparse(p, &p); + if (mem_size == 0) { + free(tmp_cmdline); + return -EINVAL; + } + mem_limit = mem_size; + } + } + + free(tmp_cmdline); + return 0; +} + /* * In theory, KASLR can put the kernel anywhere in the range of [16M, 64T). * The mem_avoid array is used to store the ranges that need to be avoided @@ -323,7 +376,7 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, /* We don't need to set a mapping for setup_data. */ /* Mark the memmap regions we need to avoid */ - mem_avoid_memmap(); + handle_mem_memmap(); #ifdef CONFIG_X86_VERBOSE_BOOTUP /* Make sure video RAM can be used. */ @@ -432,7 +485,8 @@ static void process_e820_entry(struct boot_e820_entry *entry, { struct mem_vector region, overlap; struct slot_area slot_area; - unsigned long start_orig; + unsigned long start_orig, end; + struct boot_e820_entry cur_entry; /* Skip non-RAM entries. */ if (entry->type != E820_TYPE_RAM) @@ -446,8 +500,15 @@ static void process_e820_entry(struct boot_e820_entry *entry, if (entry->addr + entry->size < minimum) return; - region.start = entry->addr; - region.size = entry->size; + /* Ignore entries above memory limit */ + end = min(entry->size + entry->addr, mem_limit); + if (entry->addr >= end) + return; + cur_entry.addr = entry->addr; + cur_entry.size = end - entry->addr; + + region.start = cur_entry.addr; + region.size = cur_entry.size; /* Give up if slot area array is full. */ while (slot_area_index < MAX_SLOT_AREA) { @@ -461,7 +522,7 @@ static void process_e820_entry(struct boot_e820_entry *entry, region.start = ALIGN(region.start, CONFIG_PHYSICAL_ALIGN); /* Did we raise the address above this e820 region? */ - if (region.start > entry->addr + entry->size) + if (region.start > cur_entry.addr + cur_entry.size) return; /* Reduce size by any delta from the original address. */ diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 00241c8..a0838ab 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -411,3 +411,8 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, debug_putstr("done.\nBooting the kernel.\n"); return output; } + +void fortify_panic(const char *name) +{ + error("detected buffer overflow"); +} diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/pagetable.c index 1d78f17..28029be 100644 --- a/arch/x86/boot/compressed/pagetable.c +++ b/arch/x86/boot/compressed/pagetable.c @@ -63,7 +63,7 @@ static void *alloc_pgt_page(void *context) static struct alloc_pgt_data pgt_data; /* The top level page table entry pointer. */ -static unsigned long level4p; +static unsigned long top_level_pgt; /* * Mapping information structure passed to kernel_ident_mapping_init(). @@ -91,9 +91,15 @@ void initialize_identity_maps(void) * If we came here via startup_32(), cr3 will be _pgtable already * and we must append to the existing area instead of entirely * overwriting it. + * + * With 5-level paging, we use '_pgtable' to allocate the p4d page table, + * the top-level page table is allocated separately. + * + * p4d_offset(top_level_pgt, 0) would cover both the 4- and 5-level + * cases. On 4-level paging it's equal to 'top_level_pgt'. */ - level4p = read_cr3(); - if (level4p == (unsigned long)_pgtable) { + top_level_pgt = read_cr3_pa(); + if (p4d_offset((pgd_t *)top_level_pgt, 0) == (p4d_t *)_pgtable) { debug_putstr("booted via startup_32()\n"); pgt_data.pgt_buf = _pgtable + BOOT_INIT_PGT_SIZE; pgt_data.pgt_buf_size = BOOT_PGT_SIZE - BOOT_INIT_PGT_SIZE; @@ -103,7 +109,7 @@ void initialize_identity_maps(void) pgt_data.pgt_buf = _pgtable; pgt_data.pgt_buf_size = BOOT_PGT_SIZE; memset(pgt_data.pgt_buf, 0, pgt_data.pgt_buf_size); - level4p = (unsigned long)alloc_pgt_page(&pgt_data); + top_level_pgt = (unsigned long)alloc_pgt_page(&pgt_data); } } @@ -123,7 +129,7 @@ void add_identity_map(unsigned long start, unsigned long size) return; /* Build the mapping. */ - kernel_ident_mapping_init(&mapping_info, (pgd_t *)level4p, + kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, start, end); } @@ -134,5 +140,5 @@ void add_identity_map(unsigned long start, unsigned long size) */ void finalize_identity_maps(void) { - write_cr3(level4p); + write_cr3(top_level_pgt); } diff --git a/arch/x86/boot/copy.S b/arch/x86/boot/copy.S index 1eb7d29..15d9f74 100644 --- a/arch/x86/boot/copy.S +++ b/arch/x86/boot/copy.S @@ -65,23 +65,3 @@ GLOBAL(copy_to_fs) popw %es retl ENDPROC(copy_to_fs) - -#if 0 /* Not currently used, but can be enabled as needed */ -GLOBAL(copy_from_gs) - pushw %ds - pushw %gs - popw %ds - calll memcpy - popw %ds - retl -ENDPROC(copy_from_gs) - -GLOBAL(copy_to_gs) - pushw %es - pushw %gs - popw %es - calll memcpy - popw %es - retl -ENDPROC(copy_to_gs) -#endif diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index 5457b02..630e366 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -122,6 +122,14 @@ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int bas return result; } +long simple_strtol(const char *cp, char **endp, unsigned int base) +{ + if (*cp == '-') + return -simple_strtoull(cp + 1, endp, base); + + return simple_strtoull(cp, endp, base); +} + /** * strlen - Find the length of a string * @s: The string to be sized diff --git a/arch/x86/boot/string.h b/arch/x86/boot/string.h index 113588d..f274a50 100644 --- a/arch/x86/boot/string.h +++ b/arch/x86/boot/string.h @@ -22,6 +22,7 @@ extern int strcmp(const char *str1, const char *str2); extern int strncmp(const char *cs, const char *ct, size_t count); extern size_t strlen(const char *s); extern char *strstr(const char *s1, const char *s2); +extern char *strchr(const char *s, int c); extern size_t strnlen(const char *s, size_t maxlen); extern unsigned int atou(const char *s); extern unsigned long long simple_strtoull(const char *cp, char **endp, |
