From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 14 Jun 2017 10:35:37 +0000 (+0300)
Subject: xfrm: NULL dereference on allocation failure
X-Git-Tag: v3.2.93~23
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c8ae75192b35dba6dba52bd457acb6cfbc90f9ce;p=linux

xfrm: NULL dereference on allocation failure

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: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/net/key/af_key.c b/net/key/af_key.c
index 1492a1d9f32c..35fc5ba2826b 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -1152,6 +1152,7 @@ static struct xfrm_state * pfkey_msg2xfrm_state(struct net *net,
 			goto out;
 	}
 
+	err = -ENOBUFS;
 	key = ext_hdrs[SADB_EXT_KEY_AUTH - 1];
 	if (sa->sadb_sa_auth) {
 		int keysize = 0;