(0.55) Avoid crash in fillInStackTrace when threadObject is null - #22405
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Add a null check for _currentThread->threadObject in inlThrowableFillInStackTrace to prevent a crash during early JVM startup. When J9_EXTENDED_RUNTIME2_SHOW_CARRIER_FRAMES is enabled, continuation stack walking is triggered to collect carrier frames. This requires a valid threadObject, which may be uninitialized during early exceptions (e.g., during Unsafe.registerNatives). Without the check, a null dereference can occur when calling IS_JAVA_LANG_VIRTUALTHREAD. This fix ensures stack walking is only attempted when threadObject is set, preventing segmentation faults during JVM initialization. Related: eclipse-openj9#21734 Signed-off-by: Babneet Singh <sbabneet@ca.ibm.com>
pshipton
approved these changes
Aug 8, 2025
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Add a null check for
_currentThread->threadObjectininlThrowableFillInStackTraceto prevent a crash during early JVMstartup.
When
J9_EXTENDED_RUNTIME2_SHOW_CARRIER_FRAMESis enabled,continuation stack walking is triggered to collect carrier frames. This requires
a valid
threadObject, which may be uninitialized during early exceptions(e.g., during
Unsafe.registerNatives). Without the check, anulldereference can occur when calling
IS_JAVA_LANG_VIRTUALTHREAD.This fix ensures stack walking is only attempted when
threadObjectisset, preventing segmentation faults during JVM initialization.
Related: #21734
Backport of #22382