Bug ID 422328: iRules that utilize sideband connections may leak memory

Last Modified: Nov 22, 2021

Bug Tracker

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

Known Affected Versions:
11.4.0

Fixed In:
11.4.1, 11.4.0 HF3

Opened: May 30, 2013
Severity: 2-Critical
Related Article:
K14406

Symptoms

iRules that utilize sideband connections may leak memory. As a result of this issue, you may encounter the following symptoms: - The BIG-IP system becomes unresponsive or fails over to another system in the device group. - TMM may crash and generate a core in the /shared/core directory. - The TMM memory utilization graph may constantly grow.

Impact

TMM memory may eventually be exhausted and may result in a crash. If the system is configured as part of a high availability pair, the device may fail over.

Conditions

This issue occurs when all of the following conditions are met: - An iRule that makes use of a sideband connection command (connect). For example: when CLIENT_ACCEPTED { set conn_id [connect 10.10.10.10:80] close $conn_id - The virtual server associated with the iRule - The client connection to the virtual server Each time an iRule processes the connect command, the amount of memory allocated to TMM increases. This behavior may eventually cause the TMM to core.

Workaround

None. However, you can mitigate the issue by rewriting your iRule to remove any sideband commands. You can find more information in SOL14406: iRules that utilize sideband connections may leak memory, available at: http://support.f5.com/kb/en-us/solutions/public/14000/400/sol14406.html

Fix Information

The use of sideband connections no longer incorrectly causes TMM to leak memory.

Behavior Change