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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A7A33C432C0 for ; Sat, 16 Nov 2019 21:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8159120729 for ; Sat, 16 Nov 2019 21:03:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727810AbfKPVDN (ORCPT ); Sat, 16 Nov 2019 16:03:13 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:53796 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727505AbfKPVDN (ORCPT ); Sat, 16 Nov 2019 16:03:13 -0500 Received: from localhost (unknown [IPv6:2601:601:9f00:1e2::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 70772151A15FC; Sat, 16 Nov 2019 13:03:12 -0800 (PST) Date: Sat, 16 Nov 2019 13:03:12 -0800 (PST) Message-Id: <20191116.130312.1715585977428653229.davem@davemloft.net> To: mcroce@redhat.com Cc: netdev@vger.kernel.org, j.vosburgh@gmail.com, vfalico@gmail.com, andy@greyhouse.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next] bonding: symmetric ICMP transmit From: David Miller In-Reply-To: <20191115111037.7843-1-mcroce@redhat.com> References: <20191115111037.7843-1-mcroce@redhat.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sat, 16 Nov 2019 13:03:12 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matteo Croce Date: Fri, 15 Nov 2019 12:10:37 +0100 > A bonding with layer2+3 or layer3+4 hashing uses the IP addresses and the ports > to balance packets between slaves. With some network errors, we receive an ICMP > error packet by the remote host or a router. If sent by a router, the source IP > can differ from the remote host one. Additionally the ICMP protocol has no port > numbers, so a layer3+4 bonding will get a different hash than the previous one. > These two conditions could let the packet go through a different interface than > the other packets of the same flow: ... > An ICMP error packet contains the header of the packet which caused the network > error, so inspect it and match the flow against it, so we can send the ICMP via > the same interface of the previous packet in the flow. > Move the IP and port dissect code into a generic function bond_flow_ip() and if > we are dissecting an ICMP error packet, call it again with the adjusted offset. ... > Signed-off-by: Matteo Croce Applied, thanks.