diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/livepatch.c | 53 | ||||
| -rw-r--r-- | arch/x86/kernel/module.c | 43 |
3 files changed, 36 insertions, 61 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 2a7c3afa62e2..8ef4369a4f06 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -90,7 +90,6 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-y += apic/ obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o -obj-$(CONFIG_LIVEPATCH) += livepatch.o obj-$(CONFIG_FUNCTION_TRACER) += ftrace_$(BITS).o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c deleted file mode 100644 index 6a68e41206e7..000000000000 --- a/arch/x86/kernel/livepatch.c +++ /dev/null @@ -1,53 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * livepatch.c - x86-specific Kernel Live Patching Core - */ - -#include <linux/module.h> -#include <linux/kallsyms.h> -#include <linux/livepatch.h> -#include <asm/text-patching.h> - -/* Apply per-object alternatives. Based on x86 module_finalize() */ -void arch_klp_init_object_loaded(struct klp_patch *patch, - struct klp_object *obj) -{ - int cnt; - struct klp_modinfo *info; - Elf_Shdr *s, *alt = NULL, *para = NULL; - void *aseg, *pseg; - const char *objname; - char sec_objname[MODULE_NAME_LEN]; - char secname[KSYM_NAME_LEN]; - - info = patch->mod->klp_info; - objname = obj->name ? obj->name : "vmlinux"; - - /* See livepatch core code for BUILD_BUG_ON() explanation */ - BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); - - for (s = info->sechdrs; s < info->sechdrs + info->hdr.e_shnum; s++) { - /* Apply per-object .klp.arch sections */ - cnt = sscanf(info->secstrings + s->sh_name, - ".klp.arch.%55[^.].%127s", - sec_objname, secname); - if (cnt != 2) - continue; - if (strcmp(sec_objname, objname)) - continue; - if (!strcmp(".altinstructions", secname)) - alt = s; - if (!strcmp(".parainstructions", secname)) - para = s; - } - - if (alt) { - aseg = (void *) alt->sh_addr; - apply_alternatives(aseg, aseg + alt->sh_size); - } - - if (para) { - pseg = (void *) para->sh_addr; - apply_paravirt(pseg, pseg + para->sh_size); - } -} diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index d5c72cb877b3..23c95a53d20e 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -18,6 +18,7 @@ #include <linux/gfp.h> #include <linux/jump_label.h> #include <linux/random.h> +#include <linux/memory.h> #include <asm/text-patching.h> #include <asm/page.h> @@ -126,11 +127,12 @@ int apply_relocate(Elf32_Shdr *sechdrs, return 0; } #else /*X86_64*/ -int apply_relocate_add(Elf64_Shdr *sechdrs, +static int __apply_relocate_add(Elf64_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relsec, - struct module *me) + struct module *me, + void *(*write)(void *dest, const void *src, size_t len)) { unsigned int i; Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr; @@ -162,19 +164,19 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, case R_X86_64_64: if (*(u64 *)loc != 0) goto invalid_relocation; - *(u64 *)loc = val; + write(loc, &val, 8); break; case R_X86_64_32: if (*(u32 *)loc != 0) goto invalid_relocation; - *(u32 *)loc = val; + write(loc, &val, 4); if (val != *(u32 *)loc) goto overflow; break; case R_X86_64_32S: if (*(s32 *)loc != 0) goto invalid_relocation; - *(s32 *)loc = val; + write(loc, &val, 4); if ((s64)val != *(s32 *)loc) goto overflow; break; @@ -183,7 +185,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, if (*(u32 *)loc != 0) goto invalid_relocation; val -= (u64)loc; - *(u32 *)loc = val; + write(loc, &val, 4); #if 0 if ((s64)val != *(s32 *)loc) goto overflow; @@ -193,7 +195,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, if (*(u64 *)loc != 0) goto invalid_relocation; val -= (u64)loc; - *(u64 *)loc = val; + write(loc, &val, 8); break; default: pr_err("%s: Unknown rela relocation: %llu\n", @@ -215,6 +217,33 @@ overflow: me->name); return -ENOEXEC; } + +int apply_relocate_add(Elf64_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + int ret; + bool early = me->state == MODULE_STATE_UNFORMED; + void *(*write)(void *, const void *, size_t) = memcpy; + + if (!early) { + write = text_poke; + mutex_lock(&text_mutex); + } + + ret = __apply_relocate_add(sechdrs, strtab, symindex, relsec, me, + write); + + if (!early) { + text_poke_sync(); + mutex_unlock(&text_mutex); + } + + return ret; +} + #endif int module_finalize(const Elf_Ehdr *hdr, |