1 files changed, 96 insertions, 25 deletions

diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c
index a2b656b4e3d2..8fd438529fbc 100644
--- a/kernel/module/strict_rwx.c
+++ b/kernel/module/strict_rwx.c
@@ -9,15 +9,19 @@
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <linux/set_memory.h>
+#include <linux/execmem.h>
 #include "internal.h"
 
-static void module_set_memory(const struct module *mod, enum mod_mem_type type,
-			      int (*set_memory)(unsigned long start, int num_pages))
+static int module_set_memory(const struct module *mod, enum mod_mem_type type,
+			     int (*set_memory)(unsigned long start, int num_pages))
 {
 	const struct module_memory *mod_mem = &mod->mem[type];
 
+	if (!mod_mem->base)
+		return 0;
+
 	set_vm_flush_reset_perms(mod_mem->base);
-	set_memory((unsigned long)mod_mem->base, mod_mem->size >> PAGE_SHIFT);
+	return set_memory((unsigned long)mod_mem->base, mod_mem->size >> PAGE_SHIFT);
 }
 
 /*
@@ -26,41 +30,66 @@ static void module_set_memory(const struct module *mod, enum mod_mem_type type,
  * CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we
  * are strict.
  */
-void module_enable_x(const struct module *mod)
+int module_enable_text_rox(const struct module *mod)
 {
-	for_class_mod_mem_type(type, text)
-		module_set_memory(mod, type, set_memory_x);
+	for_class_mod_mem_type(type, text) {
+		const struct module_memory *mem = &mod->mem[type];
+		int ret;
+
+		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);
+		if (ret)
+			return ret;
+	}
+	return 0;
 }
 
-void module_enable_ro(const struct module *mod, bool after_init)
+int module_enable_rodata_ro(const struct module *mod)
 {
-	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
-		return;
-#ifdef CONFIG_STRICT_MODULE_RWX
-	if (!rodata_enabled)
-		return;
-#endif
+	int ret;
 
-	module_set_memory(mod, MOD_TEXT, set_memory_ro);
-	module_set_memory(mod, MOD_INIT_TEXT, set_memory_ro);
-	module_set_memory(mod, MOD_RODATA, set_memory_ro);
-	module_set_memory(mod, MOD_INIT_RODATA, set_memory_ro);
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX) || !rodata_enabled)
+		return 0;
+
+	ret = module_set_memory(mod, MOD_RODATA, set_memory_ro);
+	if (ret)
+		return ret;
+	ret = module_set_memory(mod, MOD_INIT_RODATA, set_memory_ro);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+int module_enable_rodata_ro_after_init(const struct module *mod)
+{
+	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX) || !rodata_enabled)
+		return 0;
 
-	if (after_init)
-		module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro);
+	return module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro);
 }
 
-void module_enable_nx(const struct module *mod)
+int module_enable_data_nx(const struct module *mod)
 {
 	if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
-		return;
+		return 0;
+
+	for_class_mod_mem_type(type, data) {
+		int ret = module_set_memory(mod, type, set_memory_nx);
 
-	for_class_mod_mem_type(type, data)
-		module_set_memory(mod, type, set_memory_nx);
+		if (ret)
+			return ret;
+	}
+	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;
@@ -78,3 +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;
+			}
+		}
+	}
+}