diff options
| author | Bhasker Hariharan <bhaskerh@google.com> | 2021-02-02 11:03:37 -0800 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-02-02 11:05:28 -0800 |
| commit | 8c7c5abafbd8a72a43105cc352b42e48c12a99e8 (patch) | |
| tree | 99949c5fb992f8af16e686241840ed13683df5a8 /pkg/tcpip/transport/tcp/rcv.go | |
| parent | 3817c7349de2dde950fd65dcab1f4859c095eeaf (diff) | |
Add support for rate limiting out of window ACKs.
Netstack today will send dupACK's with no rate limit for incoming out of
window segments. This can result in ACK loops for example if a TCP socket
connects to itself (actually permitted by TCP). Where the ACK sent in
response to packets being out of order itself gets considered as an out
of window segment resulting in another ACK being generated.
PiperOrigin-RevId: 355206877
Diffstat (limited to 'pkg/tcpip/transport/tcp/rcv.go')
| -rw-r--r-- | pkg/tcpip/transport/tcp/rcv.go | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/pkg/tcpip/transport/tcp/rcv.go b/pkg/tcpip/transport/tcp/rcv.go index 7a7c402c4..a5c82b8fa 100644 --- a/pkg/tcpip/transport/tcp/rcv.go +++ b/pkg/tcpip/transport/tcp/rcv.go @@ -385,7 +385,7 @@ func (r *receiver) handleRcvdSegmentClosing(s *segment, state EndpointState, clo // fails, we ignore the packet: // https://github.com/torvalds/linux/blob/v5.8/net/ipv4/tcp_input.c#L5591 if r.ep.snd.sndNxt.LessThan(s.ackNumber) { - r.ep.snd.sendAck() + r.ep.snd.maybeSendOutOfWindowAck(s) return true, nil } @@ -454,7 +454,7 @@ func (r *receiver) handleRcvdSegment(s *segment) (drop bool, err tcpip.Error) { // send an ACK and stop further processing of the segment. // This is according to RFC 793, page 68. if !r.acceptable(segSeq, segLen) { - r.ep.snd.sendAck() + r.ep.snd.maybeSendOutOfWindowAck(s) return true, nil } |