From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752610AbWKBAUO (ORCPT ); Wed, 1 Nov 2006 19:20:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752612AbWKBAUN (ORCPT ); Wed, 1 Nov 2006 19:20:13 -0500 Received: from nf-out-0910.google.com ([64.233.182.184]:39833 "EHLO nf-out-0910.google.com") by vger.kernel.org with ESMTP id S1752610AbWKBAUM (ORCPT ); Wed, 1 Nov 2006 19:20:12 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:from:to:subject:date:user-agent:cc:mime-version:content-type:content-transfer-encoding:content-disposition:message-id; b=V0K99OdH2HxTjA9KKO6e+XkOKmRUwirBfTDagZD1iF39cW4dxlTRxG9dnVxL7WqJ55LfZwJvCfZ2x5oNBFYk7XItivgLLBs+9dO3Vv0nh8EAf8Q5yUo69kJgztTHq9lO3EHqAssu5uxDzwDtu7inD35WWtbJz6I/XqjXIBIWxXg= From: Jesper Juhl To: linux-kernel@vger.kernel.org Subject: [PATCH] LLC: Avoid potential NULL dereference in net/llc/af_llc.c::llc_ui_accept() . Date: Thu, 2 Nov 2006 01:21:53 +0100 User-Agent: KMail/1.9.4 Cc: Jay Schulist , Arnaldo Carvalho de Melo , davem@davemloft.net, Jesper Juhl MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200611020121.53368.jesper.juhl@gmail.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Since skb_dequeue() may return NULL we risk dereferencing a NULL pointer at if (!skb->sk) This patch avoids that by also testing for a NULL skb. Signed-off-by: Jesper Juhl --- diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c index 2652ead..a3c885f 100644 --- a/net/llc/af_llc.c +++ b/net/llc/af_llc.c @@ -620,7 +620,7 @@ static int llc_ui_accept(struct socket * llc_sk(sk)->laddr.lsap); skb = skb_dequeue(&sk->sk_receive_queue); rc = -EINVAL; - if (!skb->sk) + if (!skb || !skb->sk) goto frees; rc = 0; newsk = skb->sk;