From patchwork Fri Aug 17 20:33:12 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jesper Juhl X-Patchwork-Id: 178359 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C82752C00AB for ; Sat, 18 Aug 2012 06:33:53 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758888Ab2HQUdR (ORCPT ); Fri, 17 Aug 2012 16:33:17 -0400 Received: from 1010ds2-suoe.0.fullrate.dk ([90.184.90.115]:11882 "EHLO swampdragon.chaosbits.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754411Ab2HQUdP (ORCPT ); Fri, 17 Aug 2012 16:33:15 -0400 Received: by swampdragon.chaosbits.net (Postfix, from userid 1000) id 4A39994057; Fri, 17 Aug 2012 22:33:13 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by swampdragon.chaosbits.net (Postfix) with ESMTP id 4382B94051; Fri, 17 Aug 2012 22:33:13 +0200 (CEST) Date: Fri, 17 Aug 2012 22:33:12 +0200 (CEST) From: Jesper Juhl To: linux-kernel@vger.kernel.org cc: netdev@vger.kernel.org, "David S. Miller" , Sjur Braendeland , Daniel Martensson Subject: [PATCH] caif: Do not dereference NULL in chnl_recv_cb() Message-ID: User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In net/caif/chnl_net.c::chnl_recv_cb() we call skb_header_pointer() which may return NULL, but we do not check for a NULL pointer before dereferencing it. This patch adds such a NULL check and properly free's allocated memory and return an error (-EINVAL) on failure - much better than crashing.. Signed-off-by: Jesper Juhl Acked-by: Sjur Brændeland --- net/caif/chnl_net.c | 4 ++++ 1 file changed, 4 insertions(+) Note: compile tested only. diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c index 69771c0..e597733 100644 --- a/net/caif/chnl_net.c +++ b/net/caif/chnl_net.c @@ -94,6 +94,10 @@ static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt) /* check the version of IP */ ip_version = skb_header_pointer(skb, 0, 1, &buf); + if (!ip_version) { + kfree_skb(skb); + return -EINVAL; + } switch (*ip_version >> 4) { case 4: