From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Leblond Subject: [PATCH v2] af-packet: fix oops when socket is not present Date: Tue, 6 Nov 2012 13:10:10 +0100 Message-ID: <1352203810-957-1-git-send-email-eric@regit.org> References: <1352201642.3140.880.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: stable@vger.kernel.org, Eric Leblond To: netdev Return-path: Received: from ks28632.kimsufi.com ([91.121.96.152]:49266 "EHLO ks28632.kimsufi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751308Ab2KFMKk (ORCPT ); Tue, 6 Nov 2012 07:10:40 -0500 In-Reply-To: <1352201642.3140.880.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: Due to a NULL dereference, the following patch is causing oops in normal trafic condition: commit c0de08d04215031d68fa13af36f347a6cfa252ca Author: Eric Leblond Date:=C2=A0=C2=A0 Thu Aug 16 22:02:58 2012 +0000 =C2=A0=C2=A0=C2=A0 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 --- 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 b4978e2..83232a1 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1666,7 +1666,7 @@ static inline int deliver_skb(struct sk_buff *skb= , =20 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_bu= ff *skb) { - if (ptype->af_packet_priv =3D=3D NULL) + if (!ptype->af_packet_priv || !skb->sk) return false; =20 if (ptype->id_match) --=20 1.7.10.4