From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18382C63799 for ; Mon, 19 Jul 2021 17:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0166361165 for ; Mon, 19 Jul 2021 17:58:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376416AbhGSRP5 (ORCPT ); Mon, 19 Jul 2021 13:15:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:35796 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346867AbhGSPjP (ORCPT ); Mon, 19 Jul 2021 11:39:15 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2F56761026; Mon, 19 Jul 2021 16:18:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626711519; bh=ohu4GLdFZVFzF+SIykILYAGTNT0w1INs83PMAbFV1Tk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PtwK3XTTZaqS3kGhcQz9u0OotzOyr96SVKUOg/5qSnUzSWCeniXz1PvsSQYt3AEQm 7ZsM31q77OEGH008A98VRJWUjszJSfHuf8tNfdB4sir72ObEo59Sn5DcL3erYNo5jC ZcvKwPK2Q5gQRRX9yHraCjP5SW88mWtHSAazdFeo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nikolay Aleksandrov , "David S. Miller" Subject: [PATCH 5.12 032/292] net: bridge: multicast: fix PIM hello router port marking race Date: Mon, 19 Jul 2021 16:51:34 +0200 Message-Id: <20210719144943.584046434@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144942.514164272@linuxfoundation.org> References: <20210719144942.514164272@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nikolay Aleksandrov commit 04bef83a3358946bfc98a5ecebd1b0003d83d882 upstream. When a PIM hello packet is received on a bridge port with multicast snooping enabled, we mark it as a router port automatically, that includes adding that port the router port list. The multicast lock protects that list, but it is not acquired in the PIM message case leading to a race condition, we need to take it to fix the race. Cc: stable@vger.kernel.org Fixes: 91b02d3d133b ("bridge: mcast: add router port on PIM hello message") Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_multicast.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -3087,7 +3087,9 @@ static void br_multicast_pim(struct net_ pim_hdr_type(pimhdr) != PIM_TYPE_HELLO) return; + spin_lock(&br->multicast_lock); br_multicast_mark_router(br, port); + spin_unlock(&br->multicast_lock); } static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,