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: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2010-08-05 12:59:10 -06:00
parent 49668688dd
commit 6526c534b2

View File

@ -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 @@ free_hdr:
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 @@ free_strmap:
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);