From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:42832 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1034177AbcIYPHq (ORCPT ); Sun, 25 Sep 2016 11:07:46 -0400 Subject: Patch "tcp: properly scale window in tcp_v[46]_reqsk_send_ack()" has been added to the 4.4-stable tree To: edumazet@google.com, davem@davemloft.net, gregkh@linuxfoundation.org, holger@applied-asynchrony.com, ncardwell@google.com, ycheng@google.com Cc: , From: Date: Sun, 25 Sep 2016 17:07:35 +0200 Message-ID: <1474816055140117@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled tcp: properly scale window in tcp_v[46]_reqsk_send_ack() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tcp-properly-scale-window-in-tcp_v_reqsk_send_ack.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>>From foo@baz Wed Sep 21 12:45:10 CEST 2016 From: Eric Dumazet Date: Mon, 22 Aug 2016 11:31:10 -0700 Subject: tcp: properly scale window in tcp_v[46]_reqsk_send_ack() From: Eric Dumazet [ Upstream commit 20a2b49fc538540819a0c552877086548cff8d8d ] When sending an ack in SYN_RECV state, we must scale the offered window if wscale option was negotiated and accepted. Tested: Following packetdrill test demonstrates the issue : 0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 // Establish a connection. +0 < S 0:0(0) win 20000 +0 > S. 0:0(0) ack 1 win 28960 +0 < . 1:11(10) ack 1 win 156 // check that window is properly scaled ! +0 > . 1:1(0) ack 1 win 226 Signed-off-by: Eric Dumazet Cc: Yuchung Cheng Cc: Neal Cardwell Acked-by: Yuchung Cheng Acked-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Tested-by: Holger Hoffstätte --- net/ipv4/tcp_ipv4.c | 8 +++++++- net/ipv6/tcp_ipv6.c | 8 +++++++- 2 files changed, 14 insertions(+), 2 deletions(-) --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -808,8 +808,14 @@ static void tcp_v4_reqsk_send_ack(const u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt; + /* RFC 7323 2.3 + * The window field (SEG.WND) of every outgoing segment, with the + * exception of segments, MUST be right-shifted by + * Rcv.Wind.Shift bits: + */ tcp_v4_send_ack(sock_net(sk), skb, seq, - tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, + tcp_rsk(req)->rcv_nxt, + req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, tcp_time_stamp, req->ts_recent, 0, --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -932,9 +932,15 @@ static void tcp_v6_reqsk_send_ack(const /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV * sk->sk_state == TCP_SYN_RECV -> for Fast Open. */ + /* RFC 7323 2.3 + * The window field (SEG.WND) of every outgoing segment, with the + * exception of segments, MUST be right-shifted by + * Rcv.Wind.Shift bits: + */ tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, - tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd, + tcp_rsk(req)->rcv_nxt, + req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, tcp_time_stamp, req->ts_recent, sk->sk_bound_dev_if, tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr), 0, 0); Patches currently in stable-queue which might be from edumazet@google.com are queue-4.4/tcp-properly-scale-window-in-tcp_v_reqsk_send_ack.patch queue-4.4/tcp-fix-use-after-free-in-tcp_xmit_retransmit_queue.patch