From patchwork Wed Apr 22 21:40:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Ahern X-Patchwork-Id: 220724 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=-15.1 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 66CF8C54FCB for ; Wed, 22 Apr 2020 21:40:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31F5B20857 for ; Wed, 22 Apr 2020 21:40:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587591625; bh=q7gvLfkKNG0l/eA45XopwzvMK2nkm9+t3mU297up0fI=; h=From:To:Cc:Subject:Date:List-ID:From; b=enXo4XTbZIXmZj7ri7Av1k6VoMhym8eIJbUAzY3Is1TtspWrxQ8e1959TqRjGGk2z 9XVR7Y0cL1Ms6wLs/XHiVz2XL5GsNuqj3q+V1XzXe1R8/u74yR0WHrftDLL8Mvsti/ PXmMOlKfVaZlMKl25S1/bINVsx1UqqnK22SNEcnU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726147AbgDVVkY (ORCPT ); Wed, 22 Apr 2020 17:40:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:58224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726006AbgDVVkX (ORCPT ); Wed, 22 Apr 2020 17:40:23 -0400 Received: from C02YQ0RWLVCF.internal.digitalocean.com (c-73-181-34-237.hsd1.co.comcast.net [73.181.34.237]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E9D8B20781; Wed, 22 Apr 2020 21:40:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587591623; bh=q7gvLfkKNG0l/eA45XopwzvMK2nkm9+t3mU297up0fI=; h=From:To:Cc:Subject:Date:From; b=hioCJ5L0WJYgZzPGTOFlW72rKu589dMcjojrmUD+o78FVbYDSY2N9832+jS+eNH34 ZxTlV8OWkTVskMWcKuPoqKRPbnWy/V0ODYc6HssGOkBI3ySzpxxKCXX2Ib3n0CHY4D rCMn6REawEYcGrPR6mMie/3TlmsGilnJvI/3Ejjg= From: David Ahern To: davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, David Ahern Subject: [PATCH net] ipv4: Update fib_select_default to handle nexthop objects Date: Wed, 22 Apr 2020 15:40:20 -0600 Message-Id: <20200422214020.72107-1-dsahern@kernel.org> X-Mailer: git-send-email 2.21.1 (Apple Git-122.3) MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: David Ahern A user reported [0] hitting the WARN_ON in fib_info_nh: [ 8633.839816] ------------[ cut here ]------------ [ 8633.839819] WARNING: CPU: 0 PID: 1719 at include/net/nexthop.h:251 fib_select_path+0x303/0x381 ... [ 8633.839846] RIP: 0010:fib_select_path+0x303/0x381 ... [ 8633.839848] RSP: 0018:ffffb04d407f7d00 EFLAGS: 00010286 [ 8633.839850] RAX: 0000000000000000 RBX: ffff9460b9897ee8 RCX: 00000000000000fe [ 8633.839851] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 [ 8633.839852] RBP: ffff946076049850 R08: 0000000059263a83 R09: ffff9460840e4000 [ 8633.839853] R10: 0000000000000014 R11: 0000000000000000 R12: ffffb04d407f7dc0 [ 8633.839854] R13: ffffffffa4ce3240 R14: 0000000000000000 R15: ffff9460b7681f60 [ 8633.839857] FS: 00007fcac2e02700(0000) GS:ffff9460bdc00000(0000) knlGS:0000000000000000 [ 8633.839858] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8633.839859] CR2: 00007f27beb77e28 CR3: 0000000077734000 CR4: 00000000000006f0 [ 8633.839867] Call Trace: [ 8633.839871] ip_route_output_key_hash_rcu+0x421/0x890 [ 8633.839873] ip_route_output_key_hash+0x5e/0x80 [ 8633.839876] ip_route_output_flow+0x1a/0x50 [ 8633.839878] __ip4_datagram_connect+0x154/0x310 [ 8633.839880] ip4_datagram_connect+0x28/0x40 [ 8633.839882] __sys_connect+0xd6/0x100 ... The WARN_ON is triggered in fib_select_default which is invoked when there are multiple default routes. Update the function to use fib_info_nhc and convert the nexthop checks to use fib_nh_common. Add test case that covers the affected code path. [0] https://github.com/FRRouting/frr/issues/6089 Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Signed-off-by: David Ahern --- net/ipv4/fib_semantics.c | 6 +++--- tools/testing/selftests/net/fib_nexthops.sh | 23 +++++++++++++++++++++ 2 files changed, 26 insertions(+), 3 deletions(-) diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 6ed8c9317179..55ca2e521828 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -2014,7 +2014,7 @@ static void fib_select_default(const struct flowi4 *flp, struct fib_result *res) hlist_for_each_entry_rcu(fa, fa_head, fa_list) { struct fib_info *next_fi = fa->fa_info; - struct fib_nh *nh; + struct fib_nh_common *nhc; if (fa->fa_slen != slen) continue; @@ -2037,8 +2037,8 @@ static void fib_select_default(const struct flowi4 *flp, struct fib_result *res) fa->fa_type != RTN_UNICAST) continue; - nh = fib_info_nh(next_fi, 0); - if (!nh->fib_nh_gw4 || nh->fib_nh_scope != RT_SCOPE_LINK) + nhc = fib_info_nhc(next_fi, 0); + if (!nhc->nhc_gw_family || nhc->nhc_scope != RT_SCOPE_LINK) continue; fib_alias_accessed(fa); diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh index 796670ebc65b..6560ed796ac4 100755 --- a/tools/testing/selftests/net/fib_nexthops.sh +++ b/tools/testing/selftests/net/fib_nexthops.sh @@ -749,6 +749,29 @@ ipv4_fcnal_runtime() run_cmd "ip netns exec me ping -c1 -w1 172.16.101.1" log_test $? 0 "Ping - multipath" + run_cmd "$IP ro delete 172.16.101.1/32 nhid 122" + + # + # multiple default routes + # - tests fib_select_default + run_cmd "$IP nexthop add id 501 via 172.16.1.2 dev veth1" + run_cmd "$IP ro add default nhid 501" + run_cmd "$IP ro add default via 172.16.1.3 dev veth1 metric 20" + run_cmd "ip netns exec me ping -c1 -w1 172.16.101.1" + log_test $? 0 "Ping - multiple default routes, nh first" + + # flip the order + run_cmd "$IP ro del default nhid 501" + run_cmd "$IP ro del default via 172.16.1.3 dev veth1 metric 20" + run_cmd "$IP ro add default via 172.16.1.2 dev veth1 metric 20" + run_cmd "$IP nexthop replace id 501 via 172.16.1.3 dev veth1" + run_cmd "$IP ro add default nhid 501 metric 20" + run_cmd "ip netns exec me ping -c1 -w1 172.16.101.1" + log_test $? 0 "Ping - multiple default routes, nh second" + + run_cmd "$IP nexthop delete nhid 501" + run_cmd "$IP ro del default" + # # IPv4 with blackhole nexthops #