From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755227AbdLLNJO (ORCPT ); Tue, 12 Dec 2017 08:09:14 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:34538 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755136AbdLLNAQ (ORCPT ); Tue, 12 Dec 2017 08:00:16 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hannes Frederic Sowa , Xin Long , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 122/148] route: also update fnhe_genid when updating a route cache Date: Tue, 12 Dec 2017 13:45:32 +0100 Message-Id: <20171212124437.597975198@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171212124431.207182779@linuxfoundation.org> References: <20171212124431.207182779@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit cebe84c6190d741045a322f5343f717139993c08 ] Now when ip route flush cache and it turn out all fnhe_genid != genid. If a redirect/pmtu icmp packet comes and the old fnhe is found and all it's members but fnhe_genid will be updated. Then next time when it looks up route and tries to rebind this fnhe to the new dst, the fnhe will be flushed due to fnhe_genid != genid. It causes this redirect/pmtu icmp packet acutally not to be applied. This patch is to also reset fnhe_genid when updating a route cache. Fixes: 5aad1de5ea2c ("ipv4: use separate genid for next hop exceptions") Acked-by: Hannes Frederic Sowa Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/ipv4/route.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -630,9 +630,12 @@ static void update_or_create_fnhe(struct struct fnhe_hash_bucket *hash; struct fib_nh_exception *fnhe; struct rtable *rt; + u32 genid, hval; unsigned int i; int depth; - u32 hval = fnhe_hashfun(daddr); + + genid = fnhe_genid(dev_net(nh->nh_dev)); + hval = fnhe_hashfun(daddr); spin_lock_bh(&fnhe_lock); @@ -655,6 +658,8 @@ static void update_or_create_fnhe(struct } if (fnhe) { + if (fnhe->fnhe_genid != genid) + fnhe->fnhe_genid = genid; if (gw) fnhe->fnhe_gw = gw; if (pmtu) { @@ -679,7 +684,7 @@ static void update_or_create_fnhe(struct fnhe->fnhe_next = hash->chain; rcu_assign_pointer(hash->chain, fnhe); } - fnhe->fnhe_genid = fnhe_genid(dev_net(nh->nh_dev)); + fnhe->fnhe_genid = genid; fnhe->fnhe_daddr = daddr; fnhe->fnhe_gw = gw; fnhe->fnhe_pmtu = pmtu;