diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-03 13:40:38 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-03 13:40:38 -0700 |
commit | 25e09ca52459586eb6171209635bc8b436a56d79 (patch) | |
tree | 405d1a8387cf1df44c9e42f17d83b060d42a098f /arch/x86 | |
parent | 48b5259cf0a2b86b978da122f9459e22a2d1e8f6 (diff) | |
parent | fe2d48b805d01e14ddb8144de01de43171eb516f (diff) |
Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
"The main changes in this cycle were KASLR improvements for rare
environments with special boot options, by Baoquan He. Also misc
smaller changes/cleanups"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Extend the lower bound of crash kernel low reservations
x86/boot: Remove unused copy_*_gs() functions
x86/KASLR: Use the right memcpy() implementation
Documentation/kernel-parameters.txt: Update 'memmap=' boot option description
x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options
x86/KASLR: Parse all 'memmap=' boot option entries
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/boot/compressed/cmdline.c | 2 | ||||
-rw-r--r-- | arch/x86/boot/compressed/kaslr.c | 191 | ||||
-rw-r--r-- | arch/x86/boot/copy.S | 20 | ||||
-rw-r--r-- | arch/x86/boot/string.c | 8 | ||||
-rw-r--r-- | arch/x86/kernel/setup.c | 2 |
5 files changed, 136 insertions, 87 deletions
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c index 73ccf63b0f48..9dc1ce6ba3c0 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/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 56a7e9201741..91f27ab970ef 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/copy.S b/arch/x86/boot/copy.S index 1eb7d298b47d..15d9f74b0008 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 5457b02fc050..630e3664906b 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/kernel/setup.c b/arch/x86/kernel/setup.c index f81823695014..65622f07e633 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -503,7 +503,7 @@ static int __init reserve_crashkernel_low(void) return 0; } - low_base = memblock_find_in_range(low_size, 1ULL << 32, low_size, CRASH_ALIGN); + low_base = memblock_find_in_range(0, 1ULL << 32, low_size, CRASH_ALIGN); if (!low_base) { pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", (unsigned long)(low_size >> 20)); |