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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 ADFE1C432C0 for ; Tue, 3 Dec 2019 22:46:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E90A20803 for ; Tue, 3 Dec 2019 22:46:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413180; bh=/vaTvR14aracHKWxFI1nwBvHEUr4TWkn1zIqaBp2qOk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KXcuarjodYLBgWJAY5Uj9gHWJgGL4HrSkWPr3wHHWnDg1hxSvuMUoRAOietIE20NN IzXtjWGxVKU08fgrysQBJcd7MzDyqvdqpn+PvdWcXDNlIEF/mmB/j0Oft/8lS6z+jc J9RtaoMEY+jC4zfPY7jQByGSdSfMIl+VeTSzZBuk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729170AbfLCWqT (ORCPT ); Tue, 3 Dec 2019 17:46:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:35502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729161AbfLCWqK (ORCPT ); Tue, 3 Dec 2019 17:46:10 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 AA02A20656; Tue, 3 Dec 2019 22:46:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575413170; bh=/vaTvR14aracHKWxFI1nwBvHEUr4TWkn1zIqaBp2qOk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jlTLm3wEFf37C6x/tO3OuDXzI+vye9ugJpII41KmkzI0DOS/Y/y0O1c/FaJsfuGxF 4eH2LjNLlH0XTGV/H6Drbztb/KjXyHSapLao8j+o0RSm7OQJ/7kv38L3pTUe78QDf3 1Q0UyOTUawILFsn9whpvYlok5SIdmUxqGgQo8U+Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tom Yan , =?UTF-8?q?Linus=20L=C3=BCssing?= , Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.19 025/321] bridge: ebtables: dont crash when using dnat target in output chains Date: Tue, 3 Dec 2019 23:31:31 +0100 Message-Id: <20191203223428.428836835@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191203223427.103571230@linuxfoundation.org> References: <20191203223427.103571230@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: Florian Westphal [ Upstream commit b23c0742c2ce7e33ed79d10e451f70fdb5ca85d1 ] xt_in() returns NULL in the output hook, skip the pkt_type change for that case, redirection only makes sense in broute/prerouting hooks. Reported-by: Tom Yan Cc: Linus Lüssing Fixes: cf3cb246e277d ("bridge: ebtables: fix reception of frames DNAT-ed to bridge device/port") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/bridge/netfilter/ebt_dnat.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/net/bridge/netfilter/ebt_dnat.c b/net/bridge/netfilter/ebt_dnat.c index dfc86a0199dab..1d8c834d90189 100644 --- a/net/bridge/netfilter/ebt_dnat.c +++ b/net/bridge/netfilter/ebt_dnat.c @@ -19,7 +19,6 @@ static unsigned int ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par) { const struct ebt_nat_info *info = par->targinfo; - struct net_device *dev; if (!skb_make_writable(skb, 0)) return EBT_DROP; @@ -32,10 +31,22 @@ ebt_dnat_tg(struct sk_buff *skb, const struct xt_action_param *par) else skb->pkt_type = PACKET_MULTICAST; } else { - if (xt_hooknum(par) != NF_BR_BROUTING) - dev = br_port_get_rcu(xt_in(par))->br->dev; - else + const struct net_device *dev; + + switch (xt_hooknum(par)) { + case NF_BR_BROUTING: dev = xt_in(par); + break; + case NF_BR_PRE_ROUTING: + dev = br_port_get_rcu(xt_in(par))->br->dev; + break; + default: + dev = NULL; + break; + } + + if (!dev) /* NF_BR_LOCAL_OUT */ + return info->target; if (ether_addr_equal(info->mac, dev->dev_addr)) skb->pkt_type = PACKET_HOST; -- 2.20.1