use size_t for pixel count in wuffs png loader#657
Merged
Conversation
solidpixel
approved these changes
Jul 8, 2026
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
num_pixels = dim_x * dim_yis evaluated in 32-bit and wraps once the pixel count reaches 2^32 (65536x65536 truncates to 0, 65536x65537 to 65536).num_pixels > SIZE_MAX / 4guard on the next line and sizes the pixbuf allocation, so the oversize rejection never fires and the buffer is under-sized for the real dimensions.Widened the first multiply to size_t so the count and the guard are computed at full width, matching the sizing in alloc_image and the KTX/DDS/ASTC loaders. Wuffs' own slice-length check still rejects the mismatch today, so this keeps the guard correct rather than fixing a live overflow.