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=-7.1 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 122CAC2F3A0 for ; Mon, 21 Jan 2019 13:59:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D5A012084C for ; Mon, 21 Jan 2019 13:59:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079142; bh=hD8guslAjE26GdE0K9YvJPRDwpw6LMCAA6eG+APF6MQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UZ8w/AXAKTjpC806h7ZK8H4E4mK9REImWh7ahbf6moIv7GpNmLRjYPDbW5JwpUQTJ CV7+P4shF7Ehix2HTzl0Kmc+oGRO1QojGNeaSF4yyh5avivuRF67f7xqhWQEwABH/L Bi7dqkkyaqe3OTVBggrb7Rzao/C1sUuqePs/P/7k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732119AbfAUN7B (ORCPT ); Mon, 21 Jan 2019 08:59:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:44788 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732101AbfAUN66 (ORCPT ); Mon, 21 Jan 2019 08:58:58 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 184F02084C; Mon, 21 Jan 2019 13:58:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079137; bh=hD8guslAjE26GdE0K9YvJPRDwpw6LMCAA6eG+APF6MQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VigK2BCSBmfPXPvTHf7S+fjEB+4rrn3JGNk249VOIcRI9ZPVJ7pM5lB84UlpopFGN bGYSU8yk5Xk2cVmwbWju2QaaqtReqSMwst5wdRLBEESTJVSESDwNeKNQArnXQA7UEB EwWeTE0wknDlHLajy9ZEqzaj0Mnibe/qwfDUe7z4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, JianJhen Chen , JinLin Chen , "David S. Miller" Subject: [PATCH 4.19 21/99] net: bridge: fix a bug on using a neighbour cache entry without checking its state Date: Mon, 21 Jan 2019 14:48:13 +0100 Message-Id: <20190121134914.714915835@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190121134913.924726465@linuxfoundation.org> References: <20190121134913.924726465@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: JianJhen Chen [ Upstream commit 4c84edc11b76590859b1e45dd676074c59602dc4 ] When handling DNAT'ed packets on a bridge device, the neighbour cache entry from lookup was used without checking its state. It means that a cache entry in the NUD_STALE state will be used directly instead of entering the NUD_DELAY state to confirm the reachability of the neighbor. This problem becomes worse after commit 2724680bceee ("neigh: Keep neighbour cache entries if number of them is small enough."), since all neighbour cache entries in the NUD_STALE state will be kept in the neighbour table as long as the number of cache entries does not exceed the value specified in gc_thresh1. This commit validates the state of a neighbour cache entry before using the entry. Signed-off-by: JianJhen Chen Reviewed-by: JinLin Chen Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_netfilter_hooks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -278,7 +278,7 @@ int br_nf_pre_routing_finish_bridge(stru struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); int ret; - if (neigh->hh.hh_len) { + if ((neigh->nud_state & NUD_CONNECTED) && neigh->hh.hh_len) { neigh_hh_bridge(&neigh->hh, skb); skb->dev = nf_bridge->physindev; ret = br_handle_frame_finish(net, sk, skb);