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

Last Modified: Dec 18, 2024

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

Known Affected Versions:
14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 14.1.3.1, 14.1.4, 14.1.4.1, 14.1.4.2, 14.1.4.3, 14.1.4.4, 14.1.4.5, 14.1.4.6, 14.1.5, 14.1.5.1, 14.1.5.2, 14.1.5.3, 14.1.5.4, 14.1.5.6, 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, 15.1.10.5, 15.1.10.6, 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

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips