diff options
| -rw-r--r-- | arch/x86/kernel/livepatch.c | 25 | ||||
| -rw-r--r-- | kernel/livepatch/core.c | 16 |
2 files changed, 13 insertions, 28 deletions
diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c index bcc06e82a593..92fc1a51f994 100644 --- a/arch/x86/kernel/livepatch.c +++ b/arch/x86/kernel/livepatch.c @@ -20,8 +20,6 @@ #include <linux/module.h> #include <linux/uaccess.h> -#include <asm/cacheflush.h> -#include <asm/page_types.h> #include <asm/elf.h> #include <asm/livepatch.h> @@ -38,8 +36,7 @@ int klp_write_module_reloc(struct module *mod, unsigned long type, unsigned long loc, unsigned long value) { - int ret, numpages, size = 4; - bool readonly; + size_t size = 4; unsigned long val; unsigned long core = (unsigned long)mod->core_layout.base; unsigned long core_size = mod->core_layout.size; @@ -69,23 +66,5 @@ int klp_write_module_reloc(struct module *mod, unsigned long type, /* loc does not point to any symbol inside the module */ return -EINVAL; - readonly = false; - -#ifdef CONFIG_DEBUG_SET_MODULE_RONX - if (loc < core + mod->core_layout.ro_size) - readonly = true; -#endif - - /* determine if the relocation spans a page boundary */ - numpages = ((loc & PAGE_MASK) == ((loc + size) & PAGE_MASK)) ? 1 : 2; - - if (readonly) - set_memory_rw(loc & PAGE_MASK, numpages); - - ret = probe_kernel_write((void *)loc, &val, size); - - if (readonly) - set_memory_ro(loc & PAGE_MASK, numpages); - - return ret; + return probe_kernel_write((void *)loc, &val, size); } diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 94893e844e44..bc2c85c064c1 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -28,6 +28,7 @@ #include <linux/list.h> #include <linux/kallsyms.h> #include <linux/livepatch.h> +#include <asm/cacheflush.h> /** * struct klp_ops - structure for tracking registered ftrace ops structs @@ -232,7 +233,7 @@ static int klp_find_external_symbol(struct module *pmod, const char *name, static int klp_write_object_relocations(struct module *pmod, struct klp_object *obj) { - int ret; + int ret = 0; unsigned long val; struct klp_reloc *reloc; @@ -242,13 +243,16 @@ static int klp_write_object_relocations(struct module *pmod, if (WARN_ON(!obj->relocs)) return -EINVAL; + module_disable_ro(pmod); + for (reloc = obj->relocs; reloc->name; reloc++) { /* discover the address of the referenced symbol */ if (reloc->external) { if (reloc->sympos > 0) { pr_err("non-zero sympos for external reloc symbol '%s' is not supported\n", reloc->name); - return -EINVAL; + ret = -EINVAL; + goto out; } ret = klp_find_external_symbol(pmod, reloc->name, &val); } else @@ -257,18 +261,20 @@ static int klp_write_object_relocations(struct module *pmod, reloc->sympos, &val); if (ret) - return ret; + goto out; ret = klp_write_module_reloc(pmod, reloc->type, reloc->loc, val + reloc->addend); if (ret) { pr_err("relocation failed for symbol '%s' at 0x%016lx (%d)\n", reloc->name, val, ret); - return ret; + goto out; } } - return 0; +out: + module_enable_ro(pmod); + return ret; } static void notrace klp_ftrace_handler(unsigned long ip, |