Commit 6526c534 authored by Rusty Russell's avatar Rusty Russell
Browse files

module: move module args strndup_user to just before use 



Instead of copying and allocating the args and storing it in
load_info, we can just allocate them right before we need them.

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
parent 49668688

kernel/module.c

+13 −15
Original line number Diff line number Diff line
@@ -114,7 +114,7 @@ struct load_info { 
	Elf_Ehdr *hdr;

	unsigned long len;

	Elf_Shdr *sechdrs;

	char *secstrings, *args, *strtab;

	char *secstrings, *strtab;

	unsigned long *strmap;

	unsigned long symoffs, stroffs;

	struct {
@@ -2096,7 +2096,7 @@ static inline void kmemleak_load_module(const struct module *mod, 
}

#endif



/* Sets info->hdr, info->len and info->args. */

/* Sets info->hdr and info->len. */

static int copy_and_check(struct load_info *info,

			  const void __user *umod, unsigned long len,

			  const char __user *uargs)
@@ -2132,13 +2132,6 @@ static int copy_and_check(struct load_info *info, 
		goto free_hdr;

	}



	/* Now copy in args */

	info->args = strndup_user(uargs, ~0UL >> 1);

	if (IS_ERR(info->args)) {

		err = PTR_ERR(info->args);

		goto free_hdr;

	}



	info->hdr = hdr;

	info->len = len;

	return 0;
@@ -2150,7 +2143,6 @@ static int copy_and_check(struct load_info *info, 


static void free_copy(struct load_info *info)

{

	kfree(info->args);

	vfree(info->hdr);

}
@@ -2468,7 +2460,7 @@ static struct module *layout_and_allocate(struct load_info *info) 
	err = module_frob_arch_sections(info->hdr, info->sechdrs,

					info->secstrings, mod);

	if (err < 0)

		goto free_args;

		goto out;



	pcpusec = &info->sechdrs[info->index.pcpu];

	if (pcpusec->sh_size) {
@@ -2476,7 +2468,7 @@ static struct module *layout_and_allocate(struct load_info *info) 
		err = percpu_modalloc(mod,

				      pcpusec->sh_size, pcpusec->sh_addralign);

		if (err)

			goto free_args;

			goto out;

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

	}
@@ -2507,8 +2499,7 @@ static struct module *layout_and_allocate(struct load_info *info) 
	kfree(info->strmap);

free_percpu:

	percpu_modfree(mod);

free_args:

	kfree(info->args);

out:

	return ERR_PTR(err);

}
@@ -2594,7 +2585,12 @@ static noinline struct module *load_module(void __user *umod, 


	flush_module_icache(mod);



	mod->args = info.args;

	/* Now copy in args */

	mod->args = strndup_user(uargs, ~0UL >> 1);

	if (IS_ERR(mod->args)) {

		err = PTR_ERR(mod->args);

		goto free_arch_cleanup;

	}



	mod->state = MODULE_STATE_COMING;
@@ -2648,6 +2644,8 @@ static noinline struct module *load_module(void __user *umod, 
 unlock:

	mutex_unlock(&module_mutex);

	synchronize_sched();

	kfree(mod->args);

 free_arch_cleanup:

	module_arch_cleanup(mod);

 free_modinfo:

	free_modinfo(mod);