Commit da0acd7c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux 

Pull module updates from Jessica Yu:
 "Summary of modules changes for the 5.3 merge window:

   - Code fixes and cleanups

   - Fix bug where set_memory_x() wasn't being called when rodata=n

   - Fix bug where -EEXIST was being returned for going modules

   - Allow arches to override module_exit_section()"

* tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  modules: fix compile error if don't have strict module rwx
  ARM: module: recognize unwind exit sections
  module: allow arch overrides for .exit section names
  modules: fix BUG when load module with rodata=n
  kernel/module: Fix mem leak in module_add_modinfo_attrs
  kernel: module: Use struct_size() helper
  kernel/module.c: Only return -EEXIST for modules that have finished loading
parents 818e95c7 93651f80

arch/arm/kernel/module.c

+7 −0
Original line number Diff line number Diff line
@@ -55,6 +55,13 @@ void *module_alloc(unsigned long size) 
}

#endif



bool module_exit_section(const char *name)

{

	return strstarts(name, ".exit") ||

		strstarts(name, ".ARM.extab.exit") ||

		strstarts(name, ".ARM.exidx.exit");

}



int

apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,

	       unsigned int relindex, struct module *module)

include/linux/moduleloader.h

+5 −0
Original line number Diff line number Diff line
@@ -29,6 +29,11 @@ void *module_alloc(unsigned long size); 
/* Free memory returned from module_alloc. */

void module_memfree(void *module_region);



/* Determines if the section name is an exit section (that is only used during

 * module unloading)

 */

bool module_exit_section(const char *name);



/*

 * Apply the given relocation to the (simplified) ELF.  Return -error

 * or 0.

kernel/module.c

+41 −19
Original line number Diff line number Diff line
@@ -1492,8 +1492,7 @@ static void add_sect_attrs(struct module *mod, const struct load_info *info) 
	for (i = 0; i < info->hdr->e_shnum; i++)

		if (!sect_empty(&info->sechdrs[i]))

			nloaded++;

	size[0] = ALIGN(sizeof(*sect_attrs)

			+ nloaded * sizeof(sect_attrs->attrs[0]),

	size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),

			sizeof(sect_attrs->grp.attrs[0]));

	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);

	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
@@ -1697,6 +1696,8 @@ static int add_usage_links(struct module *mod) 
	return ret;

}



static void module_remove_modinfo_attrs(struct module *mod, int end);



static int module_add_modinfo_attrs(struct module *mod)

{

	struct module_attribute *attr;
@@ -1711,24 +1712,34 @@ static int module_add_modinfo_attrs(struct module *mod) 
		return -ENOMEM;



	temp_attr = mod->modinfo_attrs;

	for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {

	for (i = 0; (attr = modinfo_attrs[i]); i++) {

		if (!attr->test || attr->test(mod)) {

			memcpy(temp_attr, attr, sizeof(*temp_attr));

			sysfs_attr_init(&temp_attr->attr);

			error = sysfs_create_file(&mod->mkobj.kobj,

					&temp_attr->attr);

			if (error)

				goto error_out;

			++temp_attr;

		}

	}



	return 0;



error_out:

	if (i > 0)

		module_remove_modinfo_attrs(mod, --i);

	return error;

}



static void module_remove_modinfo_attrs(struct module *mod)

static void module_remove_modinfo_attrs(struct module *mod, int end)

{

	struct module_attribute *attr;

	int i;



	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {

		if (end >= 0 && i > end)

			break;

		/* pick a field to test for end of list */

		if (!attr->attr.name)

			break;
@@ -1816,7 +1827,7 @@ static int mod_sysfs_setup(struct module *mod, 
	return 0;



out_unreg_modinfo_attrs:

	module_remove_modinfo_attrs(mod);

	module_remove_modinfo_attrs(mod, -1);

out_unreg_param:

	module_param_sysfs_remove(mod);

out_unreg_holders:
@@ -1852,7 +1863,7 @@ static void mod_sysfs_fini(struct module *mod) 
{

}



static void module_remove_modinfo_attrs(struct module *mod)

static void module_remove_modinfo_attrs(struct module *mod, int end)

{

}
@@ -1868,14 +1879,14 @@ static void init_param_lock(struct module *mod) 
static void mod_sysfs_teardown(struct module *mod)

{

	del_usage_links(mod);

	module_remove_modinfo_attrs(mod);

	module_remove_modinfo_attrs(mod, -1);

	module_param_sysfs_remove(mod);

	kobject_put(mod->mkobj.drivers_dir);

	kobject_put(mod->holders_dir);

	mod_sysfs_fini(mod);

}



#ifdef CONFIG_STRICT_MODULE_RWX

#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX

/*

 * LKM RO/NX protection: protect module's text/ro-data

 * from modification and any data from execution.
@@ -1898,6 +1909,7 @@ static void frob_text(const struct module_layout *layout, 
		   layout->text_size >> PAGE_SHIFT);

}



#ifdef CONFIG_STRICT_MODULE_RWX

static void frob_rodata(const struct module_layout *layout,

			int (*set_memory)(unsigned long start, int num_pages))

{
@@ -1949,13 +1961,9 @@ void module_enable_ro(const struct module *mod, bool after_init) 
	set_vm_flush_reset_perms(mod->core_layout.base);

	set_vm_flush_reset_perms(mod->init_layout.base);

	frob_text(&mod->core_layout, set_memory_ro);

	frob_text(&mod->core_layout, set_memory_x);



	frob_rodata(&mod->core_layout, set_memory_ro);



	frob_text(&mod->init_layout, set_memory_ro);

	frob_text(&mod->init_layout, set_memory_x);



	frob_rodata(&mod->init_layout, set_memory_ro);



	if (after_init)
@@ -2014,9 +2022,19 @@ void set_all_modules_text_ro(void) 
	}

	mutex_unlock(&module_mutex);

}

#else

#else /* !CONFIG_STRICT_MODULE_RWX */

static void module_enable_nx(const struct module *mod) { }

#endif

#endif /*  CONFIG_STRICT_MODULE_RWX */

static void module_enable_x(const struct module *mod)

{

	frob_text(&mod->core_layout, set_memory_x);

	frob_text(&mod->init_layout, set_memory_x);

}

#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */

static void module_enable_nx(const struct module *mod) { }

static void module_enable_x(const struct module *mod) { }

#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */





#ifdef CONFIG_LIVEPATCH

/*
@@ -2723,6 +2741,11 @@ void * __weak module_alloc(unsigned long size) 
	return vmalloc_exec(size);

}



bool __weak module_exit_section(const char *name)

{

	return strstarts(name, ".exit");

}



#ifdef CONFIG_DEBUG_KMEMLEAK

static void kmemleak_load_module(const struct module *mod,

				 const struct load_info *info)
@@ -2912,7 +2935,7 @@ static int rewrite_section_headers(struct load_info *info, int flags) 


#ifndef CONFIG_MODULE_UNLOAD

		/* Don't load .exit sections */

		if (strstarts(info->secstrings+shdr->sh_name, ".exit"))

		if (module_exit_section(info->secstrings+shdr->sh_name))

			shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;

#endif

	}
@@ -3390,8 +3413,7 @@ static bool finished_loading(const char *name) 
	sched_annotate_sleep();

	mutex_lock(&module_mutex);

	mod = find_module_all(name, strlen(name), true);

	ret = !mod || mod->state == MODULE_STATE_LIVE

		|| mod->state == MODULE_STATE_GOING;

	ret = !mod || mod->state == MODULE_STATE_LIVE;

	mutex_unlock(&module_mutex);



	return ret;
@@ -3581,8 +3603,7 @@ again: 
	mutex_lock(&module_mutex);

	old = find_module_all(mod->name, strlen(mod->name), true);

	if (old != NULL) {

		if (old->state == MODULE_STATE_COMING

		    || old->state == MODULE_STATE_UNFORMED) {

		if (old->state != MODULE_STATE_LIVE) {

			/* Wait in case it fails to load. */

			mutex_unlock(&module_mutex);

			err = wait_event_interruptible(module_wq,
@@ -3621,6 +3642,7 @@ static int complete_formation(struct module *mod, struct load_info *info) 


	module_enable_ro(mod, false);

	module_enable_nx(mod);

	module_enable_x(mod);



	/* Mark state as coming so strong_try_module_get() ignores us,

	 * but kallsyms etc. can see us. */

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