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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 A399AC433EF for ; Sun, 8 Sep 2019 13:00:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6BC062067B for ; Sun, 8 Sep 2019 13:00:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567947624; bh=/Q7HlGJnekc1Ftvo7Rzqe8mCBBoL7JmB5U5mLKnD57U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nQzpfDzr1QUKbb6ah0P4cH0Cr6T2h655tT1XcMVaG5sNs9lktftwd3csa/cnpBHBm //O9oSOoZgtvT06nlqMeRGA1vp+/TbaRTHWFrAv8qJCW8uHAZm2Zcr5niK80HoRY/S N5j+lJGaHSULuYl4qE8wF1uEar5ugMWSJjaGlBm0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729873AbfIHMol (ORCPT ); Sun, 8 Sep 2019 08:44:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:59456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729846AbfIHMoi (ORCPT ); Sun, 8 Sep 2019 08:44:38 -0400 Received: from localhost (unknown [62.28.240.114]) (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 4BD9B218AF; Sun, 8 Sep 2019 12:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567946677; bh=/Q7HlGJnekc1Ftvo7Rzqe8mCBBoL7JmB5U5mLKnD57U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yEHrAR1bmByBnaXjo7gQvsPLWO/dIUxop0trqCtY5soG759IElzvh+h9vXkS7noe1 pFMkO9H1wcYuc1EeSuNATpyIChmrMqtpfun4Z0mH41frtTnt501h6xS4eEs3H967db knMGE1VcAWDJwzq+Dhv9pLdP7rL368eZXhDJ5CAM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Willem de Bruijn , Eric Dumazet , "David S. Miller" Subject: [PATCH 4.9 25/26] tcp: inherit timestamp on mtu probe Date: Sun, 8 Sep 2019 13:42:04 +0100 Message-Id: <20190908121111.224659994@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190908121057.216802689@linuxfoundation.org> References: <20190908121057.216802689@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Willem de Bruijn [ Upstream commit 888a5c53c0d8be6e98bc85b677f179f77a647873 ] TCP associates tx timestamp requests with a byte in the bytestream. If merging skbs in tcp_mtu_probe, migrate the tstamp request. Similar to MSG_EOR, do not allow moving a timestamp from any segment in the probe but the last. This to avoid merging multiple timestamps. Tested with the packetdrill script at https://github.com/wdebruij/packetdrill/commits/mtu_probe-1 Link: http://patchwork.ozlabs.org/patch/1143278/#2232897 Fixes: 4ed2d765dfac ("net-timestamp: TCP timestamping") Signed-off-by: Willem de Bruijn Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/tcp_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1943,7 +1943,7 @@ static bool tcp_can_coalesce_send_queue_ if (len <= skb->len) break; - if (unlikely(TCP_SKB_CB(skb)->eor)) + if (unlikely(TCP_SKB_CB(skb)->eor) || tcp_has_tx_tstamp(skb)) return false; len -= skb->len; @@ -2066,6 +2066,7 @@ static int tcp_mtu_probe(struct sock *sk * we need to propagate it to the new skb. */ TCP_SKB_CB(nskb)->eor = TCP_SKB_CB(skb)->eor; + tcp_skb_collapse_tstamp(nskb, skb); tcp_unlink_write_queue(skb, sk); sk_wmem_free_skb(sk, skb); } else {