| Message ID | 1429629853-20561-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a1bbebb03490..486f70050563 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3068,10 +3068,11 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, if (!first_ackt.v64) first_ackt = last_ackt; - if (!(sacked & TCPCB_SACKED_ACKED)) + if (!(sacked & TCPCB_SACKED_ACKED)) { reord = min(pkts_acked, reord); - if (!after(scb->end_seq, tp->high_seq)) - flag |= FLAG_ORIG_SACK_ACKED; + if (!after(scb->end_seq, tp->high_seq)) + flag |= FLAG_ORIG_SACK_ACKED; + } } if (sacked & TCPCB_SACKED_ACKED)
This is a note to let you know that I have just added a patch titled tcp: fix FRTO undo on cumulative ACK of SACKed range to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt10. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 39ae67b0556feb25f9b477e144395fadcd49c252 Mon Sep 17 00:00:00 2001 From: Neal Cardwell <ncardwell@google.com> Date: Wed, 1 Apr 2015 20:26:46 -0400 Subject: tcp: fix FRTO undo on cumulative ACK of SACKed range commit 666b805150efd62f05810ff0db08f44a2370c937 upstream. On processing cumulative ACKs, the FRTO code was not checking the SACKed bit, meaning that there could be a spurious FRTO undo on a cumulative ACK of a previously SACKed skb. The FRTO code should only consider a cumulative ACK to indicate that an original/unretransmitted skb is newly ACKed if the skb was not yet SACKed. The effect of the spurious FRTO undo would typically be to make the connection think that all previously-sent packets were in flight when they really weren't, leading to a stall and an RTO. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Fixes: e33099f96d99c ("tcp: implement RFC5682 F-RTO") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- net/ipv4/tcp_input.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)