Bug ID 911853: Stream filter chunk-size limits filter to a single match per ingress buffer

Last Modified: Jul 23, 2021

Bug Tracker

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

Known Affected Versions:
16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2

Fixed In:
16.1.0

Opened: May 26, 2020
Severity: 4-Minor

Symptoms

The chunk-size profile setting of the stream filter limits memory by capping the match string allocated from an ingress buffer to <chunksize> bytes. This implicitly limits the maximum size of the match, potentially resulting in missed matches beyond chunk-size within the same ingress buffer. For more information, see: https://support.f5.com/csp/article/K39394712

Impact

Potential matches beyond the configured chunk-size will be sent unmodified by the stream filter, potentially resulting in missed matches.

Conditions

A stream filter is configured with the chunk-size parameter set and ingress data arrives which contains matches beyond the configured chunk-size in the buffer.

Workaround

None.

Fix Information

The stream filter can now successfully find and replace matches beyond chunk-size within a single ingress buffer.

Behavior Change