diff options
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 26 |
1 files changed, 9 insertions, 17 deletions
diff --git a/kernel/module.c b/kernel/module.c index 0e2da8695f8..6085f5ef88e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2421,25 +2421,17 @@ static inline void kmemleak_load_module(const struct module *mod, #ifdef CONFIG_MODULE_SIG static int module_sig_check(struct load_info *info, - const void *mod, unsigned long *len) + const void *mod, unsigned long *_len) { int err = -ENOKEY; - const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; - const void *p = mod, *end = mod + *len; - - /* Poor man's memmem. */ - while ((p = memchr(p, MODULE_SIG_STRING[0], end - p))) { - if (p + markerlen > end) - break; - - if (memcmp(p, MODULE_SIG_STRING, markerlen) == 0) { - const void *sig = p + markerlen; - /* Truncate module up to signature. */ - *len = p - mod; - err = mod_verify_sig(mod, *len, sig, end - sig); - break; - } - p++; + unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; + unsigned long len = *_len; + + if (len > markerlen && + memcmp(mod + len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { + /* We truncate the module to discard the signature */ + *_len -= markerlen; + err = mod_verify_sig(mod, _len); } if (!err) { |