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| author | Ben Hutchings <ben@decadent.org.uk> | 2016-04-28 09:24:01 +0930 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-08-20 11:53:23 +0200 |
| commit | fc77c4ad276a03ac9217e7db44339003ba1de6bd (patch) | |
| tree | 667caf2a47bf15454ed798baa74970c046033193 /kernel | |
| parent | b7aca820d3b93fa028ecb2077b482587a26beeb6 (diff) | |
| download | linux-stable-fc77c4ad276a03ac9217e7db44339003ba1de6bd.tar.gz linux-stable-fc77c4ad276a03ac9217e7db44339003ba1de6bd.tar.bz2 linux-stable-fc77c4ad276a03ac9217e7db44339003ba1de6bd.zip | |
module: Invalidate signatures on force-loaded modules
commit bca014caaa6130e57f69b5bf527967aa8ee70fdd upstream.
Signing a module should only make it trusted by the specific kernel it
was built for, not anything else. Loading a signed module meant for a
kernel with a different ABI could have interesting effects.
Therefore, treat all signatures as invalid when a module is
force-loaded.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/module.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/kernel/module.c b/kernel/module.c index 3a311a1d26d7..6113c5a536b8 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2449,13 +2449,18 @@ static inline void kmemleak_load_module(const struct module *mod, #endif #ifdef CONFIG_MODULE_SIG -static int module_sig_check(struct load_info *info) +static int module_sig_check(struct load_info *info, int flags) { int err = -ENOKEY; const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; const void *mod = info->hdr; - if (info->len > markerlen && + /* + * Require flags == 0, as a module with version information + * removed is no longer the module that was signed + */ + if (flags == 0 && + info->len > markerlen && memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { /* We truncate the module to discard the signature */ info->len -= markerlen; @@ -2477,7 +2482,7 @@ static int module_sig_check(struct load_info *info) return err; } #else /* !CONFIG_MODULE_SIG */ -static int module_sig_check(struct load_info *info) +static int module_sig_check(struct load_info *info, int flags) { return 0; } @@ -3210,7 +3215,7 @@ static int load_module(struct load_info *info, const char __user *uargs, struct module *mod; long err; - err = module_sig_check(info); + err = module_sig_check(info, flags); if (err) goto free_copy; |