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/stack/stack.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/stack/stack.go')
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index 57ad412a1..a51d758d0 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -458,6 +458,18 @@ type Stack struct { // receiveBufferSize holds the min/default/max receive buffer sizes for // endpoints other than TCP. receiveBufferSize ReceiveBufferSizeOption + + // tcpInvalidRateLimit is the maximal rate for sending duplicate + // acknowledgements in response to incoming TCP packets that are for an existing + // connection but that are invalid due to any of the following reasons: + // + // a) out-of-window sequence number. + // b) out-of-window acknowledgement number. + // c) PAWS check failure (when implemented). + // + // This is required to prevent potential ACK loops. + // Setting this to 0 will disable all rate limiting. + tcpInvalidRateLimit time.Duration } // UniqueID is an abstract generator of unique identifiers. @@ -668,6 +680,7 @@ func New(opts Options) *Stack { Default: DefaultBufferSize, Max: DefaultMaxBufferSize, }, + tcpInvalidRateLimit: defaultTCPInvalidRateLimit, } // Add specified network protocols. |