From patchwork Fri Jun 3 19:21:06 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Holler X-Patchwork-Id: 98640 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 87532B6FAD for ; Sat, 4 Jun 2011 05:31:15 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753942Ab1FCTaw (ORCPT ); Fri, 3 Jun 2011 15:30:52 -0400 Received: from h1446028.stratoserver.net ([85.214.92.142]:44184 "EHLO mail.ahsoftware.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751797Ab1FCTav (ORCPT ); Fri, 3 Jun 2011 15:30:51 -0400 X-Greylist: delayed 576 seconds by postgrey-1.27 at vger.kernel.org; Fri, 03 Jun 2011 15:30:51 EDT Received: by mail.ahsoftware.de (Postfix, from userid 65534) id 818AB4345A9; Fri, 3 Jun 2011 21:21:14 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.ahsoftware.de X-Spam-Level: X-Spam-Status: No, score=-101.0 required=5.0 tests=ALL_TRUSTED, USER_IN_WHITELIST autolearn=disabled version=3.3.1 Received: from eiche.ahsoftware (p57B20263.dip0.t-ipconnect.de [87.178.2.99]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.ahsoftware.de (Postfix) with ESMTPSA id A29EC434276; Fri, 3 Jun 2011 21:21:13 +0200 (CEST) Received: by eiche.ahsoftware (Postfix, from userid 65534) id D56873FCBC; Fri, 3 Jun 2011 21:21:12 +0200 (CEST) Received: from krabat.ahsoftware (unknown [192.168.207.2]) by eiche.ahsoftware (Postfix) with ESMTP id 4F6083FC69; Fri, 3 Jun 2011 19:21:06 +0000 (UTC) Message-ID: <4DE93422.3070000@ahsoftware.de> Date: Fri, 03 Jun 2011 21:21:06 +0200 From: Alexander Holler User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc13 Lightning/1.0b3pre Thunderbird/3.1.10 MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: Eric Dumazet , David Miller , Herbert Xu , netdev@vger.kernel.org Subject: bridge/netfilter: regression in 2.6.39.1 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hello, I'm getting a oops in the bridge code in br_change_mtu() with 2.6.39.1. The patch below seems to fix that. I'm not sure about the usage of dst_cow_metrics_generic() in fake_dst_ops, but after having a quick look at it seems to be ok to use that here. Regards, Alexander ----- From 3c1d5951af73389798afeea672ec224e195b8e8d Mon Sep 17 00:00:00 2001 From: Alexander Holler Date: Fri, 3 Jun 2011 20:43:06 +0200 Subject: [PATCH] bridge: add dst_cow_metrics_generic to fake_dst_ops Commit 42923465fb8d025a2b5153f2e7ab1e6e1058bf00 does here what it should prevent, it introduces NULL a dereference. The above commit uses dst_init_metrics() which sets the metrics as read only. As result br_change_mtu() dies in dst_metric_set() which calls dst_metrics_write_ptr() which calls dst->ops->cow_metrics() if the metrics are read only. --- net/bridge/br_netfilter.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 5f9c091..de982a1 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -107,6 +107,7 @@ static void fake_update_pmtu(struct dst_entry *dst, u32 mtu) static struct dst_ops fake_dst_ops = { .family = AF_INET, .protocol = cpu_to_be16(ETH_P_IP), + .cow_metrics = dst_cow_metrics_generic, .update_pmtu = fake_update_pmtu, };