From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753163AbdLBQEd (ORCPT ); Sat, 2 Dec 2017 11:04:33 -0500 Received: from omzsmtpe03.verizonbusiness.com ([199.249.25.208]:37349 "EHLO omzsmtpe03.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752937AbdLBPyY (ORCPT ); Sat, 2 Dec 2017 10:54:24 -0500 From: alexander.levin@verizon.com Cc: Xin Long , "David S . Miller" , alexander.levin@verizon.com X-Host: surveyor.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 4.4 03/20] route: also update fnhe_genid when updating a route cache Thread-Topic: [PATCH AUTOSEL for 4.4 03/20] route: also update fnhe_genid when updating a route cache Thread-Index: AQHTa4WczxUlVjRv9UC72Uq+Ccm2Gw== Date: Sat, 2 Dec 2017 15:52:52 +0000 Message-ID: <20171202155243.7774-3-alexander.levin@verizon.com> References: <20171202155243.7774-1-alexander.levin@verizon.com> In-Reply-To: <20171202155243.7774-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vB2G5KL1022745 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 --- net/ipv4/route.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 0294f7c99c85..a6d9369864f5 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -624,9 +624,12 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, 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); @@ -649,6 +652,8 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, } if (fnhe) { + if (fnhe->fnhe_genid != genid) + fnhe->fnhe_genid = genid; if (gw) fnhe->fnhe_gw = gw; if (pmtu) { @@ -673,7 +678,7 @@ static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, 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; -- 2.11.0