Fix WeakTag type confusion via unchecked ObjectInfo::Unwrap #1 - #2
Merged
urbanogilson merged 2 commits intoJul 28, 2026
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
ObjectWrap<T>::Unwrap()has no way to verify the JS object it's given was actually constructed asT, it's justnapi_unwrap()+ a blindstatic_cast.WeakTagrelied on this to unwrapObjectInfoinstances, so passing aWeakTag(or any other object) where anObjectInfowas expected returned a non-null pointer of the wrong type.The
info_ == nullptrguard didn't catch it, and WeakTag's destructor later dereferenced the mistyped pointer, corrupting memory and crashing V8 during GC.Tag every ObjectInfo instance with a node-api type tag at construction and have WeakTag check that tag before trusting the unwrapped pointer, so mistyped arguments now throw instead of crashing.