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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 351DAC10F27 for ; Tue, 10 Mar 2020 13:20:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 031D2208E4 for ; Tue, 10 Mar 2020 13:20:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583846458; bh=tXedHrave03/djjKK4IkV0L4IAg1gcrgsCOHOyc8TsY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UIGz/AMOPzpaDtoTi4m67fsqJtD7vTM9CgRvxylJTKpnXztnfDw1AKdFTD8ilg80D yVp9W/RAyptF+KL6pgwkDYtV0JB/tuKiAxclXkofJxrWOv2Rd2gQyGyZIqeJ7Pd2JP Xvdc7XawMiVmNgZ1KL9t5JHkev1eMpa/ZJLIHFeY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727678AbgCJNU5 (ORCPT ); Tue, 10 Mar 2020 09:20:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:52184 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728891AbgCJNGe (ORCPT ); Tue, 10 Mar 2020 09:06:34 -0400 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 EC96D20409; Tue, 10 Mar 2020 13:06:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583845594; bh=tXedHrave03/djjKK4IkV0L4IAg1gcrgsCOHOyc8TsY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cua6HE9G8853Jlf7H/kejj+CpSCTNvhWcRTeh1VmjTMgG4pqDPnRTEDkaaxuA0RxH ghzycMKkg/lxN+FeBq7iQf4yGEzHCSHDEm/YUA86UoB4w92OBwv87YQFb47+ETCw0R YlUNbTNrucn3WYxLFQwEzH7FBbwMD2D3RkpZZUp4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Benjamin Poirier , Michal Kubecek , "David S. Miller" Subject: [PATCH 4.14 031/126] ipv6: Fix route replacement with dev-only route Date: Tue, 10 Mar 2020 13:40:52 +0100 Message-Id: <20200310124206.419779637@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200310124203.704193207@linuxfoundation.org> References: <20200310124203.704193207@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Benjamin Poirier [ Upstream commit e404b8c7cfb31654c9024d497cec58a501501692 ] After commit 27596472473a ("ipv6: fix ECMP route replacement") it is no longer possible to replace an ECMP-able route by a non ECMP-able route. For example, ip route add 2001:db8::1/128 via fe80::1 dev dummy0 ip route replace 2001:db8::1/128 dev dummy0 does not work as expected. Tweak the replacement logic so that point 3 in the log of the above commit becomes: 3. If the new route is not ECMP-able, and no matching non-ECMP-able route exists, replace matching ECMP-able route (if any) or add the new route. We can now summarize the entire replace semantics to: When doing a replace, prefer replacing a matching route of the same "ECMP-able-ness" as the replace argument. If there is no such candidate, fallback to the first route found. Fixes: 27596472473a ("ipv6: fix ECMP route replacement") Signed-off-by: Benjamin Poirier Reviewed-by: Michal Kubecek Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ip6_fib.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -893,8 +893,7 @@ static int fib6_add_rt2node(struct fib6_ found++; break; } - if (rt_can_ecmp) - fallback_ins = fallback_ins ?: ins; + fallback_ins = fallback_ins ?: ins; goto next_iter; } @@ -934,7 +933,9 @@ next_iter: } if (fallback_ins && !found) { - /* No ECMP-able route found, replace first non-ECMP one */ + /* No matching route with same ecmp-able-ness found, replace + * first matching route + */ ins = fallback_ins; iter = *ins; found++;