Bug ID 1881569: Programs invoked by tmsh when session is interrupted may remain running

Last Modified: Apr 12, 2025

Affected Product(s):
BIG-IP TMOS(all modules)

Known Affected Versions:
16.1.5, 16.1.5.1, 16.1.5.2, 17.1.2, 17.1.2.1, 17.5.0

Opened: Mar 24, 2025

Severity: 3-Major

Symptoms

If an interactive user session is interrupted while a tmsh process is executing another command (e.g. bash), under particular circumstances the child process may continue executing. This occurs if the bash process is itself executing a long-running command (e.g. 'watch' or 'tcpdump' or similar), and then the SSH connection is interrupted.

Impact

Processes remain executing even after they should have been terminated because the user session disconnected. If the long-running command the bash process is executing tries to invoke tmsh, the LTM log file may contain repeated logs similar to the following: Mar 25 12:10:00 hostname notice tmsh[22420]: 01420003:5: Cannot load user credentials for user "username" Mar 25 12:10:00 hostname notice tmsh[22420]: 01420003:5: The current session has been terminated.

Conditions

-- An interactive tmsh process runs another program (e.g. bash) -- That bash process is executing another command that will not generally exit on its own without user intervention (e.g. 'watch' or 'tcpdump') -- The user session is interrupted

Workaround

Avoid unclean shutdown/interruption of user sessions if possible. Otherwise, identify the long-running processes that are still running, and then kill them.

Fix Information

None

Behavior Change

Guides & references

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