Work around UB in LMDB bindings #6211
Merged
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Outdated suggestions cannot be applied.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 Addressed
Fix a crazy memory corruption bug in the LMDB slasher impl.
Proposed Changes
Copy the contents of the cursor's
value
prior to returning it, so that LMDB can't mutate the data being pointed to when.delete_current()
is called.Additional Info
This possibly explains the strange behaviour seen on some slasher nodes:
The bug had existed latently for a long time, but only now became executable with the refactor in: