sheinbergon opened a new pull request, #29547:
URL: https://github.com/apache/flink/pull/29547

   ## What is the purpose of the change
   
   Since JDK 24 the Java Security Manager is permanently disabled ([JEP 
486](https://openjdk.org/jeps/486)): `System#setSecurityManager` always throws 
`UnsupportedOperationException`, even when passed `null`. 
`FlinkSecurityManager#forceProcessExit` called it unconditionally, so on JDK 
24+ the fatal-error paths (`FatalExitExceptionHandler`, 
`ClusterEntrypoint#onFatalError`, `TaskManagerRunner#terminateJVM`) threw 
instead of terminating the JVM and left the process running. This is also why 
`ClusterUncaughtExceptionHandlerITCase` had to be tagged `FailsOnJava25`.
   
   This PR makes the exit helpers independent of an installed Security Manager 
and reports a clear error when the Security Manager based options are enabled 
on a JVM that cannot install one. Behaviour on JDK 11-23 is unchanged. Full 
removal of `FlinkSecurityManager` and `cluster.intercept-user-system-exit` (as 
attempted in #26491) is intentionally out of scope and needs a dev-list 
discussion first.
   
   ## Brief change log
   
     - `FlinkSecurityManager#forceProcessExit` / `#checkExit` only unset the 
Security Manager when one is actually installed, which can never be the case on 
JDK 24+.
     - Enabling `cluster.intercept-user-system-exit` or 
`cluster.processes.halt-on-fatal-error` without Security Manager support (JDK 
24+, or JDK 18-23 without `-Djava.security.manager=allow`) fails with a message 
naming JEP 486 and the options to disable, instead of a misleading "no 
permission" error.
     - `ExecutorThreadFactory` no longer consults `System#getSecurityManager` 
for the thread group (the lookup was a no-op).
     - Option descriptions document the JDK 24+ limitation; configuration docs 
regenerated.
     - `ClusterUncaughtExceptionHandlerITCase` untagged from `FailsOnJava25`; 
`TestJvmProcess` gained a `getJvmArgs()` hook.
   
   ## Verifying this change
   
   This change added tests and can be verified as follows:
   
     - `FlinkSecurityManagerITCase#testForcedJVMExitWithoutSecurityManager`: a 
child JVM calls `forceProcessExit` without any Security Manager configured and 
must exit with the requested code. Fails on JDK 25 without the fix 
(`UnsupportedOperationException: Setting a Security Manager is not supported`).
     - `FlinkSecurityManagerITCase#testUnavailableSecurityManagerIsReported`: a 
child JVM started with `-Djava.security.manager=disallow` must fail with the 
descriptive `IllegalConfigurationException`. Runs on JDK 12+.
     - `ClusterUncaughtExceptionHandlerITCase` passes on JDK 25 again (hung 
before the fix).
     - Existing `FlinkSecurityManagerTest` and the `FailsOnJava25`-tagged tests 
are unchanged and pass on JDK 21.
   
   Verified locally on JDK 21 and JDK 25 (Zulu).
   
   ## Does this pull request potentially affect one of the following parts:
   
     - Dependencies (does it add or upgrade a dependency): no
     - The public API, i.e., is any changed class annotated with 
`@Public(Evolving)`: no
     - The serializers: no
     - The runtime per-record code paths (performance sensitive): no
     - Anything that affects deployment or recovery: JobManager (and its 
components), Checkpointing, Kubernetes/Yarn, ZooKeeper: yes - 
JobManager/TaskManager fatal-error exit on JDK 24+ now terminates the process 
as intended
     - The S3 file system connector: no
   
   ## Documentation
   
     - Does this pull request introduce a new feature? no
     - If yes, how is the feature documented? not applicable (option 
descriptions updated for the JDK 24+ limitation)
   
   ---
   
   ##### Was generative AI tooling used to co-author this PR?
   
   - [X] Yes (please specify the tool below)
   
   Generated-by: Claude Code (Claude Fable 5.1)


-- 
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.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to