Fix ClassDB crash caused by HashMap reallocation invalidating parent_ptr#1886
Closed
SiimonDev wants to merge 1 commit into
Closed
Fix ClassDB crash caused by HashMap reallocation invalidating parent_ptr#1886SiimonDev wants to merge 1 commit into
SiimonDev wants to merge 1 commit into
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
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Issue:
Currently, ClassInfo stores a parent_ptr that points to the parent class's entry inside the global classes HashMap. However, HashMap stores elements contiguously. When new classes are registered and the map exceeds its capacity, it triggers a resize/reallocation. This moves all existing ClassInfo objects to new memory addresses. Any existing parent_ptr held by child classes becomes a dangling pointer to freed memory. This causes random crashes in get_virtual_func when looking up parent methods, depending on registration order and memory reuse.
Proposed Fix:
Remove parent_ptr and replace it with a dynamic lookup using classes.find(parent_name).
This is the first time doing any kind of pull-requests so if anything looks wrong please let me know.