Reject NaN and out-of-range blur radii - #9902
Open
lazerg wants to merge 2 commits into
Open
Conversation
akx
reviewed
Aug 25, 2026
| } | ||
| if (xradius < 0 || yradius < 0) { | ||
| /* Negated comparisons, so that NaN is rejected as well. */ | ||
| if (!(xradius >= 0) || !(yradius >= 0)) { |
Contributor
There was a problem hiding this comment.
To a casual reader, this looks like a very odd way to write the thing. If the idea is that this catches NaNs by... off the top of my head, some quirk of how IEEE floats work, a comment would be nice.
EDIT: a comment got added just as I was writing this. Nice!
Even nicer, though, I think, some sort of reusable float-validation function since I'm quite sure there are many other instances of this same class of bug in Pillow.
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Fixes #9900. Alternative to #9906
Changes proposed in this pull request:
ImagingBoxBlur()only rejected negative radii, so NaN slipped through and(int)floatRadiuswas undefined behaviour, giving a garbage radius and the out of bounds write inImagingLineBoxBlur32(). Infinity and any radius of2**31or more crash the same way, since they are not representable as aninteither.int, which coversGaussianBlurtoo.