fix(Worklets): time-of-check and time-of-use destructor safety#9790
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Pull request overview
This PR hardens destructor-time cleanup of JSI values by eliminating a time-of-check/time-of-use window when deciding whether it’s safe to run JSI destructors while a runtime may be concurrently tearing down.
Changes:
- Replace atomic “is dead” checks with mutex-protected, locked execution for RN runtime status.
- Update
SerializableRemoteFunctionand genericcleanupRuntimeAwarecleanup paths to perform “check + destroy” while holding the relevant lifetime lock. - Refactor
WorkletRuntimeRegistryfrom a boolean query API to arunWhileLockedAPI to support atomic check+action.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
| packages/react-native-worklets/Common/cpp/worklets/Tools/RNRuntimeStatus.h | Switches runtime-dead tracking from atomic reads to mutex-locked execution. |
| packages/react-native-worklets/Common/cpp/worklets/SharedItems/SerializableRemoteFunction.cpp | Uses the new locked runtime-status path to safely reset/free remote functions during destruction. |
| packages/react-native-worklets/Common/cpp/worklets/SharedItems/Serializable.h | Updates runtime-aware cleanup to use registry-locked “alive check + destroy” semantics. |
| packages/react-native-worklets/Common/cpp/worklets/Registries/WorkletRuntimeRegistry.h | Replaces isRuntimeAlive with a runWhileLocked helper to prevent TOCTOU. |
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bartlomiejbloniarz
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Jun 30, 2026
tjzel
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## Summary Currently the way we check if the runtime is alive for safe destructor invocations has a chance to lead to crashes anyway, since the runtime can get cleaned up immediately after the check, since it lacks a locking mechanism. ## Test plan The test example from #9789 works. (cherry picked from commit 71774cb)
tjzel
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## Summary Currently the way we check if the runtime is alive for safe destructor invocations has a chance to lead to crashes anyway, since the runtime can get cleaned up immediately after the check, since it lacks a locking mechanism. ## Test plan The test example from #9789 works. (cherry picked from commit 71774cb)
This was referenced Jul 9, 2026
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## Summary Currently the way we check if the runtime is alive for safe destructor invocations has a chance to lead to crashes anyway, since the runtime can get cleaned up immediately after the check, since it lacks a locking mechanism. ## Test plan The test example from #9789 works. (cherry picked from commit 71774cb)
tjzel
added a commit
that referenced
this pull request
Jul 14, 2026
## Summary Currently the way we check if the runtime is alive for safe destructor invocations has a chance to lead to crashes anyway, since the runtime can get cleaned up immediately after the check, since it lacks a locking mechanism. ## Test plan The test example from #9789 works. (cherry picked from commit 71774cb)
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Summary
Currently the way we check if the runtime is alive for safe destructor invocations has a chance to lead to crashes anyway, since the runtime can get cleaned up immediately after the check, since it lacks a locking mechanism.
Test plan
The test example from #9789 works.