[skif] Don't assume SkSpecialImage::asShader() is non-null
Adds checks that FilterResult::imageAndOffset is non-null, and that
that image's SkShader is also non-null. These can occur if the offscreen
surface for resolving the FilterResult fails to be created, or if the
sampling/other parameters to asShader() are invalid.
Bug: oss-fuzz:58713, chromium:1425773
Change-Id: Idefc870760ea9119acca59894a29ccabc70e79dc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/696538
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
1 file changed