Bug ID 1078357: HTTP_REJECT processing can lead to zombie SPAWN flows

Last Modified: Apr 17, 2024

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

Known Affected Versions:
15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2, 16.1.0, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 17.0.0, 17.0.0.1, 17.0.0.2

Opened: Feb 04, 2022

Severity: 3-Major

Symptoms

Due to the presence of a specific set of events in the iRule, the Bloom filter may cause TCL to execute an event that is not implemented in the iRule. In the execution of a sequence of events, when TCL attempts to execute the non-existing event, it follows a path which in turn makes SPAWN flow to become a zombie.

Impact

Causes issues with monitoring system

Conditions

-- http2, client-ssl, optimised-caching filters on the virtual server -- HTTP::respond iRule with LB_FAILED event and set of iRules like HTTP_REQUEST, HTTP_RESPONSE, CLIENTSSL_HANDSHAKE, CACHE_RESPONSE, ASM_REQUEST_BLOCKING -- send http2 request through the virtual server

Workaround

None

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips