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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 EC568C43441 for ; Wed, 21 Nov 2018 19:09:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB3F8214DB for ; Wed, 21 Nov 2018 19:09:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ie+qF3ub" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB3F8214DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388408AbeKVFo5 (ORCPT ); Thu, 22 Nov 2018 00:44:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:39644 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732102AbeKVFo4 (ORCPT ); Thu, 22 Nov 2018 00:44:56 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 4FEB52151B; Wed, 21 Nov 2018 19:09:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542827363; bh=2YFwkuhScewqe8aBtyleyHBQTNGxa2yBKZ8rPd+7ZWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ie+qF3ubEKWqSW1lsTRJDSJjwlHmER6FEn92abqSXdhvTuLez6mQPl7lBCfkMVFnt YfZ5BlXOx3WJPWQN6cBnXqLk0XugXPvRCB20KNO46GaP3+fy7bZ4qvjHS8Z4AIrtvL 4jqIwiR0xbXDvOcj3xPI5HSODFMR6diModIivwpI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sabrina Dubroca , Stefano Brivio , "David S. Miller" Subject: [PATCH 4.14 03/21] ip_tunnel: dont force DF when MTU is locked Date: Wed, 21 Nov 2018 20:06:47 +0100 Message-Id: <20181121183422.241348200@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181121183422.103826775@linuxfoundation.org> References: <20181121183422.103826775@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sabrina Dubroca [ Upstream commit 16f7eb2b77b55da816c4e207f3f9440a8cafc00a ] The various types of tunnels running over IPv4 can ask to set the DF bit to do PMTU discovery. However, PMTU discovery is subject to the threshold set by the net.ipv4.route.min_pmtu sysctl, and is also disabled on routes with "mtu lock". In those cases, we shouldn't set the DF bit. This patch makes setting the DF bit conditional on the route's MTU locking state. This issue seems to be older than git history. Signed-off-by: Sabrina Dubroca Reviewed-by: Stefano Brivio Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/ip_tunnel_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/ipv4/ip_tunnel_core.c +++ b/net/ipv4/ip_tunnel_core.c @@ -80,7 +80,7 @@ void iptunnel_xmit(struct sock *sk, stru iph->version = 4; iph->ihl = sizeof(struct iphdr) >> 2; - iph->frag_off = df; + iph->frag_off = ip_mtu_locked(&rt->dst) ? 0 : df; iph->protocol = proto; iph->tos = tos; iph->daddr = dst;