From patchwork Wed Jan 26 03:36:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huang Guobin X-Patchwork-Id: 12724551 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4E03C5DF62 for ; Wed, 26 Jan 2022 03:18:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237058AbiAZDSQ (ORCPT ); Tue, 25 Jan 2022 22:18:16 -0500 Received: from szxga02-in.huawei.com ([45.249.212.188]:30305 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237038AbiAZDSH (ORCPT ); Tue, 25 Jan 2022 22:18:07 -0500 Received: from kwepemi500001.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Jk85y4wvyzbkLb; Wed, 26 Jan 2022 11:17:10 +0800 (CST) Received: from kwepeml500002.china.huawei.com (7.221.188.128) by kwepemi500001.china.huawei.com (7.221.188.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 26 Jan 2022 11:18:00 +0800 Received: from huawei.com (10.175.104.82) by kwepeml500002.china.huawei.com (7.221.188.128) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 26 Jan 2022 11:18:00 +0800 From: Huang Guobin To: , , CC: , , Subject: [PATCH 4.19 0/1] Fix UBSAN: undefined-behaviour in maybe_deliver Date: Wed, 26 Jan 2022 11:36:38 +0800 Message-ID: <20220126033639.909340-1-huangguobin4@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.104.82] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepeml500002.china.huawei.com (7.221.188.128) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org There is a syzkaller problem for Linux 4.19 last for over 1 year: https://www.syzkaller.appspot.com/bug?id=288ae4752bb930c26369d675316de0310264ee34 Mainline patch 7d850abd5f4e(net: bridge: add support for port isolation) introduces the BR_ISOLATED feature, a pair of ports with the BR_ISOLATED option set cannot communicate with each other. This feature applies only to ingress flow, not egress flow. However, the function br_skb_isolated that checks if an interface is isolated will be used not only for the ingress path, but also for the egress path. Since Linux-4.19 not merge the mainline patch fd65e5a95d0838(net: bridge: clear bridge's private skb space on xmit), the value of skb->cb is unde- fined because it is not initialized. Therefore, checking BR_INPUT_SKB_CB(skb)->src_port_isolated on the egress path will access an undefined value, resulting in an error in the judgment of br_skb_isolated. UBSAN triggers an alarm by finding undefined BR_INPUT_SKB_CB(skb)->src_port_isolated. So cherry-pick mainline patch fd65e5a95d0838(net: bridge: clear bridge's private skb space on xmit) to Linux 4.19 to fix it. Nikolay Aleksandrov (1): net: bridge: clear bridge's private skb space on xmit net/bridge/br_device.c | 2 ++ 1 file changed, 2 insertions(+)