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A framework for building native applications using React

Fix Hermes crash from TurboModule void method NSException handling (#56265)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/56265

When an async void TurboModule method throws an NSException,
performVoidMethodInvocation calls convertNSExceptionToJSError which
accesses the Hermes JSI runtime from the native method call invoker
thread. Since jsi::Runtime is not thread-safe, this causes heap
corruption and EXC_BAD_ACCESS crashes across various hermes::vm::*
functions.

The sibling function performMethodInvocation was already fixed in
D71619229 to re-throw the ObjC exception instead of converting to
JSError when the call is async. This applies the same fix to
performVoidMethodInvocation, which is always async.

Related to SEV S641230 (4,550+ Hermes crashes in AMA iOS from OTA
bundle 921191722). A JS change behind a QE/MC gate is triggering an
NSException in a void TurboModule method for non-employee users, and
this bug turns that into widespread memory corruption. This fix
prevents the crash, but the triggering diff and throwing TurboModule
still need to be identified separately.

Matches upstream GitHub issue: https://github.com/facebook/hermes/issues/1957Commits affecting the React Native open source repository must have a changelog
entry in the commit summary. Every React Native release has almost 1000 commits,
and manually categorizing these commits is very time consuming.

 ---

Changelog:
[iOS][Fixed] - Fix Hermes crash when async void TurboModule method throws NSException by re-throwing instead of converting to JSError on wrong thread

Reviewed By: javache

Differential Revision: D98660782

fbshipit-source-id: bdedc769f17d9aec4156c45d0286c6c31ca006e4
F
Fabrizio Cucci committed
4083a6ff92b0ffd4f71166848f3d7ce36172fac8
Parent: 277d6f3
Committed by meta-codesync[bot] <215208954+meta-codesync[bot]@users.noreply.github.com> on 3/29/2026, 1:49:33 PM