1 files changed, 67 insertions, 7 deletions

diff --git a/kernel/module/main.c b/kernel/module/main.c
index 49b9bca9de12..73b588fe98d4 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1189,6 +1189,18 @@ void __weak module_arch_freeing_init(struct module *mod)
 {
 }
 
+void *__module_writable_address(struct module *mod, void *loc)
+{
+	for_class_mod_mem_type(type, text) {
+		struct module_memory *mem = &mod->mem[type];
+
+		if (loc >= mem->base && loc < mem->base + mem->size)
+			return loc + (mem->rw_copy - mem->base);
+	}
+
+	return loc;
+}
+
 static int module_memory_alloc(struct module *mod, enum mod_mem_type type)
 {
 	unsigned int size = PAGE_ALIGN(mod->mem[type].size);
@@ -1206,6 +1218,23 @@ static int module_memory_alloc(struct module *mod, enum mod_mem_type type)
 	if (!ptr)
 		return -ENOMEM;
 
+	mod->mem[type].base = ptr;
+
+	if (execmem_is_rox(execmem_type)) {
+		ptr = vzalloc(size);
+
+		if (!ptr) {
+			execmem_free(mod->mem[type].base);
+			return -ENOMEM;
+		}
+
+		mod->mem[type].rw_copy = ptr;
+		mod->mem[type].is_rox = true;
+	} else {
+		mod->mem[type].rw_copy = mod->mem[type].base;
+		memset(mod->mem[type].base, 0, size);
+	}
+
 	/*
 	 * The pointer to these blocks of memory are stored on the module
 	 * structure and we keep that around so long as the module is
@@ -1219,16 +1248,17 @@ static int module_memory_alloc(struct module *mod, enum mod_mem_type type)
 	 */
 	kmemleak_not_leak(ptr);
 
-	memset(ptr, 0, size);
-	mod->mem[type].base = ptr;
-
 	return 0;
 }
 
 static void module_memory_free(struct module *mod, enum mod_mem_type type,
 			       bool unload_codetags)
 {
-	void *ptr = mod->mem[type].base;
+	struct module_memory *mem = &mod->mem[type];
+	void *ptr = mem->base;
+
+	if (mem->is_rox)
+		vfree(mem->rw_copy);
 
 	if (!unload_codetags && mod_mem_type_is_core_data(type))
 		return;
@@ -2251,6 +2281,7 @@ static int move_module(struct module *mod, struct load_info *info)
 	for_each_mod_mem_type(type) {
 		if (!mod->mem[type].size) {
 			mod->mem[type].base = NULL;
+			mod->mem[type].rw_copy = NULL;
 			continue;
 		}
 
@@ -2267,11 +2298,14 @@ static int move_module(struct module *mod, struct load_info *info)
 		void *dest;
 		Elf_Shdr *shdr = &info->sechdrs[i];
 		enum mod_mem_type type = shdr->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
+		unsigned long offset = shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK;
+		unsigned long addr;
 
 		if (!(shdr->sh_flags & SHF_ALLOC))
 			continue;
 
-		dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK);
+		addr = (unsigned long)mod->mem[type].base + offset;
+		dest = mod->mem[type].rw_copy + offset;
 
 		if (shdr->sh_type != SHT_NOBITS) {
 			/*
@@ -2293,7 +2327,7 @@ static int move_module(struct module *mod, struct load_info *info)
 		 * users of info can keep taking advantage and using the newly
 		 * minted official memory area.
 		 */
-		shdr->sh_addr = (unsigned long)dest;
+		shdr->sh_addr = addr;
 		pr_debug("\t0x%lx 0x%.8lx %s\n", (long)shdr->sh_addr,
 			 (long)shdr->sh_size, info->secstrings + shdr->sh_name);
 	}
@@ -2441,8 +2475,17 @@ int __weak module_finalize(const Elf_Ehdr *hdr,
 	return 0;
 }
 
+int __weak module_post_finalize(const Elf_Ehdr *hdr,
+				const Elf_Shdr *sechdrs,
+				struct module *me)
+{
+	return 0;
+}
+
 static int post_relocation(struct module *mod, const struct load_info *info)
 {
+	int ret;
+
 	/* Sort exception table now relocations are done. */
 	sort_extable(mod->extable, mod->extable + mod->num_exentries);
 
@@ -2454,7 +2497,24 @@ static int post_relocation(struct module *mod, const struct load_info *info)
 	add_kallsyms(mod, info);
 
 	/* Arch-specific module finalizing. */
-	return module_finalize(info->hdr, info->sechdrs, mod);
+	ret = module_finalize(info->hdr, info->sechdrs, mod);
+	if (ret)
+		return ret;
+
+	for_each_mod_mem_type(type) {
+		struct module_memory *mem = &mod->mem[type];
+
+		if (mem->is_rox) {
+			if (!execmem_update_copy(mem->base, mem->rw_copy,
+						 mem->size))
+				return -ENOMEM;
+
+			vfree(mem->rw_copy);
+			mem->rw_copy = NULL;
+		}
+	}
+
+	return module_post_finalize(info->hdr, info->sechdrs, mod);
 }
 
 /* Call module constructors. */