diff options
Diffstat (limited to 'kernel/module/strict_rwx.c')
| -rw-r--r-- | kernel/module/strict_rwx.c | 66 |
1 files changed, 59 insertions, 7 deletions
diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c index c45caa4690e5..8fd438529fbc 100644 --- a/kernel/module/strict_rwx.c +++ b/kernel/module/strict_rwx.c @@ -9,6 +9,7 @@ #include <linux/mm.h> #include <linux/vmalloc.h> #include <linux/set_memory.h> +#include <linux/execmem.h> #include "internal.h" static int module_set_memory(const struct module *mod, enum mod_mem_type type, @@ -32,9 +33,12 @@ static int module_set_memory(const struct module *mod, enum mod_mem_type type, int module_enable_text_rox(const struct module *mod) { for_class_mod_mem_type(type, text) { + const struct module_memory *mem = &mod->mem[type]; int ret; - if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) + if (mem->is_rox) + ret = execmem_restore_rox(mem->base, mem->size); + else if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) ret = module_set_memory(mod, type, set_memory_rox); else ret = module_set_memory(mod, type, set_memory_x); @@ -44,7 +48,7 @@ int module_enable_text_rox(const struct module *mod) return 0; } -int module_enable_rodata_ro(const struct module *mod, bool after_init) +int module_enable_rodata_ro(const struct module *mod) { int ret; @@ -58,12 +62,17 @@ int module_enable_rodata_ro(const struct module *mod, bool after_init) if (ret) return ret; - if (after_init) - return module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro); - return 0; } +int module_enable_rodata_ro_after_init(const struct module *mod) +{ + if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX) || !rodata_enabled) + return 0; + + return module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro); +} + int module_enable_data_nx(const struct module *mod) { if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX)) @@ -78,8 +87,9 @@ int module_enable_data_nx(const struct module *mod) return 0; } -int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, - char *secstrings, struct module *mod) +int module_enforce_rwx_sections(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, + const char *secstrings, + const struct module *mod) { const unsigned long shf_wx = SHF_WRITE | SHF_EXECINSTR; int i; @@ -97,3 +107,45 @@ int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, return 0; } + +static const char *const ro_after_init[] = { + /* + * Section .data..ro_after_init holds data explicitly annotated by + * __ro_after_init. + */ + ".data..ro_after_init", + + /* + * Section __jump_table holds data structures that are never modified, + * with the exception of entries that refer to code in the __init + * section, which are marked as such at module load time. + */ + "__jump_table", + +#ifdef CONFIG_HAVE_STATIC_CALL_INLINE + /* + * Section .static_call_sites holds data structures that need to be + * sorted and processed at module load time but are never modified + * afterwards. + */ + ".static_call_sites", +#endif +}; + +void module_mark_ro_after_init(const Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + const char *secstrings) +{ + int i, j; + + for (i = 1; i < hdr->e_shnum; i++) { + Elf_Shdr *shdr = &sechdrs[i]; + + for (j = 0; j < ARRAY_SIZE(ro_after_init); j++) { + if (strcmp(secstrings + shdr->sh_name, + ro_after_init[j]) == 0) { + shdr->sh_flags |= SHF_RO_AFTER_INIT; + break; + } + } + } +} |