Sorry for the vague title... Steps to reproduce: 1. Load the attached gif. Actual result: 1. The gif should load. From mozregression: Last good revision: cef590a6f946 First bad revision: 17de0f463944 Pushlog: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=cef590a6f946&tochange=17de0f463944 IE and Chrome can load the gif properly. p.s. Source of the gif: https://imgur.com/Y286dyS

Pushlog: https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=4553524f671f&tochange=7ee7e774e19f Regressed by: Bug 1060869

Tracking because, well, gifs are pretty popular these days. :) Seth - As this is a regression from bug 1060869, can you take this?

Hmm. So this GIF is corrupt. It reports its size as 398x233, but then its first frame is at offset (2,0) with size 398x233, which doesn't fit. Viewing the GIF in Chrome, I can see a two-pixel column on the left of the image where nothing is drawn. So what Chrome has done is decode the frames with the bad offset intact, and discard the 399th and 400th columns of pixels. That's precisely what we will do if we permit these malformed frames to be created, because when they get drawn into the compositing frame to be animated the extra data on the right side will get cut off. So we'll get the exact same behavior as Chrome here if we just ignore this error.

Here's the patch. I've confirmed that it fixes this issue.

Here's a try job: https://tbpl.mozilla.org/?tree=Try&rev=116dbf2efc71

Comment on attachment 8558419 [details] [diff] [review] Allow creation of animated frames that do not fit inside the bounds of their image Switching this one over to Jeff.

Comment on attachment 8558419 [details] [diff] [review] Allow creation of animated frames that do not fit inside the bounds of their image Josh, can you review this? Jeff is traveling and we need this on beta ASAP.

(In reply to Seth Fowler [:seth] from comment #8) > Comment on attachment 8558419 [details] [diff] [review] > Allow creation of animated frames that do not fit inside the bounds of their > image > > Josh, can you review this? Jeff is traveling and we need this on beta ASAP. Can you explain why/how bug 1060869 regressed this? Also a reftest would be good.

(In reply to Jeff Muizelaar [:jrmuizel] from comment #9) > Can you explain why/how bug 1060869 regressed this? I added the AllowedImageAndFrameDimensions function as part of the refactoring in bug 1060869 part 2, and I included this check that was not included in the pre-refactoring code. So this is just returning us to the pre-refactoring state in that respect. > Also a reftest would be good. Agreed! I will file a followup to add one. Unfortunately I don't have time to create one right now.

(In reply to Seth Fowler [:seth] from comment #10) > I will file a followup to add one. Filed bug 1130704.

Comment on attachment 8558419 [details] [diff] [review] Allow creation of animated frames that do not fit inside the bounds of their image Review of attachment 8558419 [details] [diff] [review]: ----------------------------------------------------------------- Seems reasonable.

Thanks for the review!

Pushed: https://hg.mozilla.org/integration/mozilla-inbound/rev/5f618e1b85c5

Comment on attachment 8558419 [details] [diff] [review] Allow creation of animated frames that do not fit inside the bounds of their image Approval Request Comment [Feature/regressing bug #]: 1060869 [User impact if declined]: Certain corrupt GIFs will not load. The same GIFs load in Blink and WebKit. [Describe test coverage new/current, TreeHerder]: On m-c. [Risks and why]: Low risk; returns us to the state before bug 1060869 with regards to error handling for this type of corrupt GIF. [String/UUID change made/needed]: None.

Comment on attachment 8558419 [details] [diff] [review] Allow creation of animated frames that do not fit inside the bounds of their image [Triage Comment] Since it landed in 38 and the uplift is for 36. I guess we want it for aurora (37) too.

Verified as fixed using the following environment: FF 36.0b10 Build id: 20150212154903 FF 37 Build Id: 20150212004049 FF 38 Build Id: 20150218030228 OS: Win 7 x64, Mac Os X 10.10, Ubuntu 14.03 x86