C0urante opened a new pull request #8608: URL: https://github.com/apache/kafka/pull/8608
[Jira](https://issues.apache.org/jira/browse/KAFKA-9950) MM2 is currently sharing the same `ConfigDef` object for all its connectors and tasks, which would be fine _if_ that object were used as-is. However, the `MirrorTaskConfig` class mutates the `ConfigDef` by defining additional properties, which leads to a potential `ConcurrentModificationException` during worker configuration validation and unintended inclusion of those new properties in the `ConfigDef` for the connectors which in turn is then visible via the REST API's `/connectors/{name}/config/validate` endpoint. The fix here is a one-liner that just creates a copy of the `ConfigDef` before defining new properties. A unit test is added that fails without this fix and passes with it. ### Committer Checklist (excluded from commit message) - [ ] Verify design and implementation - [ ] Verify test coverage and CI build status - [ ] Verify documentation (including upgrade notes) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org