// 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); }}
// 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);
}
}