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 9A8D4C43610 for ; Mon, 26 Nov 2018 10:53:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 649A72146F for ; Mon, 26 Nov 2018 10:53:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="X2rmLrQj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 649A72146F 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 S1727044AbeKZVr3 (ORCPT ); Mon, 26 Nov 2018 16:47:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:55664 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726138AbeKZVr3 (ORCPT ); Mon, 26 Nov 2018 16:47:29 -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 9C51721104; Mon, 26 Nov 2018 10:53:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543229625; bh=YcLRKx9cJjI5uz7QbDLc1wvpJKThjxyLlvoYwBODe/A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X2rmLrQjLrlnA3iHpgQuHJMWfHGLoT6QWiskEG6HLdacsmo3FZR1fXYm8Qkf72mLY bZpyUPWWIikekZQxE8tA+Vusds22PzKt3XbQM30CtrmKtzsRMhdlwxTG65KglU/nOC MRm9WgOALvSxQEu9Z3rZ9txwHOD+1KGbDSS7JOX8= 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 4.4 02/70] ip_tunnel: dont force DF when MTU is locked Date: Mon, 26 Nov 2018 11:50:17 +0100 Message-Id: <20181126105047.086636327@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181126105046.722096341@linuxfoundation.org> References: <20181126105046.722096341@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 4.4-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 @@ -71,7 +71,7 @@ int iptunnel_xmit(struct sock *sk, struc 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;