diff options
| author | Bhasker Hariharan <bhaskerh@google.com> | 2020-11-06 13:53:21 -0800 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2020-11-06 13:55:30 -0800 |
| commit | 9e82747d62e57ee7498c8f3f54c313917891273a (patch) | |
| tree | 731bedc71bce9ce3825f31b7f3efeb7c0e4bd363 | |
| parent | 949dc1d096aa9ac58c73cc861b95c8172d82dfcd (diff) | |
Return early in walkSACK if segment has no SACK blocks.
This avoids a needless allocation.
Updates #231
PiperOrigin-RevId: 341113160
| -rw-r--r-- | pkg/tcpip/transport/tcp/snd.go | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/pkg/tcpip/transport/tcp/snd.go b/pkg/tcpip/transport/tcp/snd.go index 6fa8d63cd..ab5fa4fb7 100644 --- a/pkg/tcpip/transport/tcp/snd.go +++ b/pkg/tcpip/transport/tcp/snd.go @@ -1285,6 +1285,10 @@ func (s *sender) checkDuplicateAck(seg *segment) (rtx bool) { // See: https://tools.ietf.org/html/draft-ietf-tcpm-rack-08#section-7.2 // steps 2 and 3. func (s *sender) walkSACK(rcvdSeg *segment) { + if len(rcvdSeg.parsedOptions.SACKBlocks) == 0 { + return + } + // Sort the SACK blocks. The first block is the most recent unacked // block. The following blocks can be in arbitrary order. sackBlocks := make([]header.SACKBlock, len(rcvdSeg.parsedOptions.SACKBlocks)) |