[PATCH 4.4 085/101] xfrm: NULL dereference on allocation failure

Greg Kroah-Hartman
2017-07-03T13:40:05Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit e747f64336fc15e1c823344942923195b800aa1e upstream.

The default error code in pfkey_msg2xfrm_state() is -ENOBUFS. We
added a new call to security_xfrm_state_alloc() which sets "err" to zero
so there several places where we can return ERR_PTR(0) if kmalloc()
fails. The caller is expecting error pointers so it leads to a NULL
dereference.

Fixes: df71837d5024 ("[LSM-IPSec]: Security association restriction.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/key/af_key.c | 1 +
1 file changed, 1 insertion(+)

--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -1135,6 +1135,7 @@ static struct xfrm_state * pfkey_msg2xfr
goto out;
}

+ err = -ENOBUFS;
key = ext_hdrs[SADB_EXT_KEY_AUTH - 1];
if (sa->sadb_sa_auth) {
int keysize = 0;