From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52665 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbbEHLMq (ORCPT ); Fri, 8 May 2015 07:12:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gerd v. Egidy" , Herbert Xu , "David S. Miller" Subject: [PATCH 3.19 2/7] route: Use ipv4_mtu instead of raw rt_pmtu Date: Fri, 8 May 2015 13:12:21 +0200 Message-Id: <20150508111055.127701510@linuxfoundation.org> In-Reply-To: <20150508111054.717693099@linuxfoundation.org> References: <20150508111054.717693099@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herbert Xu [ Upstream commit cb6ccf09d6b94bec4def1ac5cf4678d12b216474 ] The commit 3cdaa5be9e81a914e633a6be7b7d2ef75b528562 ("ipv4: Don't increase PMTU with Datagram Too Big message") broke PMTU in cases where the rt_pmtu value has expired but is smaller than the new PMTU value. This obsolete rt_pmtu then prevents the new PMTU value from being installed. Fixes: 3cdaa5be9e81 ("ipv4: Don't increase PMTU with Datagram Too Big message") Reported-by: Gerd v. Egidy Signed-off-by: Herbert Xu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/route.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -963,10 +963,7 @@ static void __ip_rt_update_pmtu(struct r if (dst_metric_locked(dst, RTAX_MTU)) return; - if (dst->dev->mtu < mtu) - return; - - if (rt->rt_pmtu && rt->rt_pmtu < mtu) + if (ipv4_mtu(dst) < mtu) return; if (mtu < ip_rt_min_pmtu)