From patchwork Thu Dec 13 13:59:29 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [204/241] af-packet: fix oops when socket is not present Date: Thu, 13 Dec 2012 03:59:29 -0000 From: Herton Ronaldo Krzesinski X-Patchwork-Id: 206050 Message-Id: <1355407206-17100-205-git-send-email-herton.krzesinski@canonical.com> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Eric Leblond , "David S. Miller" 3.5.7.2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Leblond commit a3d744e995d2b936c500585ae39d99ee251c89b4 upstream. Due to a NULL dereference, the following patch is causing oops in normal trafic condition: commit c0de08d04215031d68fa13af36f347a6cfa252ca Author: Eric Leblond Date:   Thu Aug 16 22:02:58 2012 +0000     af_packet: don't emit packet on orig fanout group This buggy patch was a feature fix and has reached most stable branches. When skb->sk is NULL and when packet fanout is used, there is a crash in match_fanout_group where skb->sk is accessed. This patch fixes the issue by returning false as soon as the socket is NULL: this correspond to the wanted behavior because the kernel as to resend the skb to all the listening socket in this case. Signed-off-by: Eric Leblond Signed-off-by: David S. Miller Signed-off-by: Herton Ronaldo Krzesinski --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index 4ef7993..75845ba 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1642,7 +1642,7 @@ static inline int deliver_skb(struct sk_buff *skb, static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) { - if (ptype->af_packet_priv == NULL) + if (!ptype->af_packet_priv || !skb->sk) return false; if (ptype->id_match)