Bug ID 624168: DATA_ACK and DATA_FIN ignored on a subflow not currently used for transmission

Last Modified: Nov 07, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP LTM(all modules)

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1

Fixed In:
13.1.0, 12.1.5

Opened: Oct 20, 2016
Severity: 4-Minor

Symptoms

During an MPTCP connection, if a DATA_ACK or DATA_FIN is received on a subflow that is not currently being used to transmit data, that DATA_ACK or DATA_FIN is ignored. Clients generally respond on the same subflow that they received data on, making this situation somewhat rare.

Impact

The DATA_ACK or DATA_FIN is ignored. If the same information is not sent on other subflows, this can cause the connection to hang until the subflow times out.

Conditions

MPTCP is in use on a connection and a DATA_ACK or DATA_FIN is received on a subflow that is not currently being used to transmit data.

Workaround

None

Fix Information

Accept DATA_ACK and DATA_FIN on any subflow.

Behavior Change