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=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 7B82DC33CB7 for ; Thu, 16 Jan 2020 19:51:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5DCFC2072B for ; Thu, 16 Jan 2020 19:51:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731448AbgAPTvD (ORCPT ); Thu, 16 Jan 2020 14:51:03 -0500 Received: from correo.us.es ([193.147.175.20]:56066 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731039AbgAPTu5 (ORCPT ); Thu, 16 Jan 2020 14:50:57 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id E334F807E2 for ; Thu, 16 Jan 2020 20:50:55 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id D46E6DA70F for ; Thu, 16 Jan 2020 20:50:55 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id C8206DA714; Thu, 16 Jan 2020 20:50:55 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id C4238DA70F; Thu, 16 Jan 2020 20:50:53 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Thu, 16 Jan 2020 20:50:53 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from salvia.here (unknown [90.77.255.23]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id A4C3742EF9E1; Thu, 16 Jan 2020 20:50:53 +0100 (CET) X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 9/9] netfilter: nat: fix ICMP header corruption on ICMP errors Date: Thu, 16 Jan 2020 20:50:44 +0100 Message-Id: <20200116195044.326614-10-pablo@netfilter.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20200116195044.326614-1-pablo@netfilter.org> References: <20200116195044.326614-1-pablo@netfilter.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Eyal Birger Commit 8303b7e8f018 ("netfilter: nat: fix spurious connection timeouts") made nf_nat_icmp_reply_translation() use icmp_manip_pkt() as the l4 manipulation function for the outer packet on ICMP errors. However, icmp_manip_pkt() assumes the packet has an 'id' field which is not correct for all types of ICMP messages. This is not correct for ICMP error packets, and leads to bogus bytes being written the ICMP header, which can be wrongfully regarded as 'length' bytes by RFC 4884 compliant receivers. Fix by assigning the 'id' field only for ICMP messages that have this semantic. Reported-by: Shmulik Ladkani Fixes: 8303b7e8f018 ("netfilter: nat: fix spurious connection timeouts") Signed-off-by: Eyal Birger Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_nat_proto.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/net/netfilter/nf_nat_proto.c b/net/netfilter/nf_nat_proto.c index 0a59c14b5177..64eedc17037a 100644 --- a/net/netfilter/nf_nat_proto.c +++ b/net/netfilter/nf_nat_proto.c @@ -233,6 +233,19 @@ icmp_manip_pkt(struct sk_buff *skb, return false; hdr = (struct icmphdr *)(skb->data + hdroff); + switch (hdr->type) { + case ICMP_ECHO: + case ICMP_ECHOREPLY: + case ICMP_TIMESTAMP: + case ICMP_TIMESTAMPREPLY: + case ICMP_INFO_REQUEST: + case ICMP_INFO_REPLY: + case ICMP_ADDRESS: + case ICMP_ADDRESSREPLY: + break; + default: + return true; + } inet_proto_csum_replace2(&hdr->checksum, skb, hdr->un.echo.id, tuple->src.u.icmp.id, false); hdr->un.echo.id = tuple->src.u.icmp.id; -- 2.11.0