From patchwork Fri Jun 1 10:34:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Kubecek X-Patchwork-Id: 923959 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=suse.cz Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 40y2F05y8sz9s1p for ; Fri, 1 Jun 2018 21:30:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752163AbeFALaG (ORCPT ); Fri, 1 Jun 2018 07:30:06 -0400 Received: from mx2.suse.de ([195.135.220.15]:54956 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751714AbeFAL3v (ORCPT ); Fri, 1 Jun 2018 07:29:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext-too.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id F0DC6AC81; Fri, 1 Jun 2018 11:29:49 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id 93BE7A0C48; Fri, 1 Jun 2018 13:29:48 +0200 (CEST) From: Michal Kubecek Date: Fri, 1 Jun 2018 12:34:41 +0200 Subject: [PATCH net] ipv6: omit traffic class when calculating flow hash To: "David S. Miller" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Nicolas Dichtel , Tom Herbert , David Ahern Message-Id: <20180601112948.93BE7A0C48@unicorn.suse.cz> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Some of the code paths calculating flow hash for IPv6 use flowlabel member of struct flowi6 which, despite its name, encodes both flow label and traffic class. If traffic class changes within a TCP connection (as e.g. ssh does), ECMP route can switch between path. It's also incosistent with other code paths where ip6_flowlabel() (returning only flow label) is used to feed the key. Use only flow label everywhere, including one place where hash key is set using ip6_flowinfo(). Fixes: 51ebd3181572 ("ipv6: add support of equal cost multipath (ECMP)") Fixes: f70ea018da06 ("net: Add functions to get skb->hash based on flow structures") Signed-off-by: Michal Kubecek Acked-by: Nicolas Dichtel --- net/core/flow_dissector.c | 3 ++- net/ipv6/route.c | 5 +++-- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index d29f09bc5ff9..441d3db76e8e 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -1334,7 +1334,8 @@ __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys) keys->ports.src = fl6->fl6_sport; keys->ports.dst = fl6->fl6_dport; keys->keyid.keyid = fl6->fl6_gre_key; - keys->tags.flow_label = (__force u32)fl6->flowlabel; + keys->tags.flow_label = (__force u32)(fl6->flowlabel & + IPV6_FLOWLABEL_MASK); keys->basic.ip_proto = fl6->flowi6_proto; return flow_hash_from_keys(keys); diff --git a/net/ipv6/route.c b/net/ipv6/route.c index f4d61736c41a..fcbacf1677f8 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1868,7 +1868,7 @@ static void ip6_multipath_l3_keys(const struct sk_buff *skb, } else { keys->addrs.v6addrs.src = key_iph->saddr; keys->addrs.v6addrs.dst = key_iph->daddr; - keys->tags.flow_label = ip6_flowinfo(key_iph); + keys->tags.flow_label = ip6_flowlabel(key_iph); keys->basic.ip_proto = key_iph->nexthdr; } } @@ -1889,7 +1889,8 @@ u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, } else { hash_keys.addrs.v6addrs.src = fl6->saddr; hash_keys.addrs.v6addrs.dst = fl6->daddr; - hash_keys.tags.flow_label = (__force u32)fl6->flowlabel; + hash_keys.tags.flow_label = (__force u32)(fl6->flowlabel & + IPV6_FLOWLABEL_MASK); hash_keys.basic.ip_proto = fl6->flowi6_proto; } break;