ext4: fix extent skip condition in Read/Write causing panic - #430
Merged
Merged
Conversation
An extent covers file blocks [fileBlock, fileBlock+count). The skip condition used a strict <, so an extent ending exactly at the current read/write start block was not skipped. With a non-block-aligned offset this made leftInExtent negative and make([]byte, n) panicked with "makeslice: len out of range". Use <= in both Read and Write
deitch
approved these changes
Aug 30, 2026
deitch
left a comment
deitch
left a comment
Collaborator
There was a problem hiding this comment.
And you used the reproduction from the issue you opened in the test; thank you for doing so.
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
An extent covers file blocks [fileBlock, fileBlock+count). The skip condition used a strict <, so an extent ending exactly at the current read/write start block was not skipped. With a non-block-aligned offset this made leftInExtent negative and make([]byte, n) panicked with "makeslice: len out of range".
Use <= in both Read and Write
Fixes #429