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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 C1A13C282CE for ; Wed, 24 Apr 2019 17:26:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 918962054F for ; Wed, 24 Apr 2019 17:26:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556126812; bh=XwvjRGdv5jLgOatDCEKJUNJ+CJZ1fcoggod5B6x0hYo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tiUOj2Cny+lo0INS2WNFHiWJxypX3i+W4C8+W+5IP+wZaRP+ufqCMy1/Hi3w9P+n5 Hcoj7bvOj7m7/6sxn9ligT0vLDqlZVgwf0hFLZRkiwbheQomPE3O8x7FkGjhNi7ee9 MoCMv45lCJF1/LX2mG50PVtwSwKBFeTRLrvl0SdQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390312AbfDXR0v (ORCPT ); Wed, 24 Apr 2019 13:26:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:52752 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390259AbfDXR0s (ORCPT ); Wed, 24 Apr 2019 13:26:48 -0400 Received: from localhost (62-193-50-229.as16211.net [62.193.50.229]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7939B2054F; Wed, 24 Apr 2019 17:26:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556126808; bh=XwvjRGdv5jLgOatDCEKJUNJ+CJZ1fcoggod5B6x0hYo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Oong8BLdJaQj5kMc1JLCcMThPJ8Z8jxlNlRPmpbUFqL9XHUdU+AD8v+lpE+UhAeGx Oeamyn/rSol9L04ona+qEzYRgu8MLjtqFuQedC+yekmW3GpxB8kQIbUds985Zz+j3E GoNwilEywsNmfOqgreLXpq4L/Yw6FwpMlrH/vJw8= 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 4.14 04/70] net: bridge: multicast: use rcu to access port list from br_multicast_start_querier Date: Wed, 24 Apr 2019 19:09:24 +0200 Message-Id: <20190424170907.791097008@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190424170906.751869122@linuxfoundation.org> References: <20190424170906.751869122@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nikolay Aleksandrov [ Upstream commit c5b493ce192bd7a4e7bd073b5685aad121eeef82 ] br_multicast_start_querier() walks over the port list but it can be called from a timer with only multicast_lock held which doesn't protect the port list, so use RCU to walk over it. Fixes: c83b8fab06fc ("bridge: Restart queries when last querier expires") Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_multicast.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -2119,7 +2119,8 @@ static void br_multicast_start_querier(s __br_multicast_open(br, query); - list_for_each_entry(port, &br->port_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(port, &br->port_list, list) { if (port->state == BR_STATE_DISABLED || port->state == BR_STATE_BLOCKING) continue; @@ -2131,6 +2132,7 @@ static void br_multicast_start_querier(s br_multicast_enable(&port->ip6_own_query); #endif } + rcu_read_unlock(); } int br_multicast_toggle(struct net_bridge *br, unsigned long val)