image/jpeg: skip consecutive 0xff bytes

[shouldend]

In all cases where markers are appended after the compressed data, optional 0xFF fill bytes may precede the marker

Fixes #40130

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[jackbrown1993]

Any update on this?

[lastzero]

Why closed?

[heschi]

Just closing PRs over a year old. I'll reopen, but I'll point out that the original author seems to have become unresponsive.

[jackbrown1993]

@heschi what are the blockers of this getting reviewed?

[heschi]

Looking at the review thread, the author would need to add test cases to the CL.

[lastzero]

This is a major bug. See https://twitter.com/lastzero/status/1452959588815413251. Brad asked for test files and I've uploaded them. What else do you need? 👀

[heschi]

I think you may be misunderstanding the code review process. The PR author needs to add test files, perhaps the one you uploaded, to the change before review can proceed. You are free to start your own PR or CL with tests and get it through the review process.

[lastzero]

Wouldn't Google have a JPEG expert who can fix a broken implementation in a core programming language? Or be so kind to ask me directly to do this instead of sitting it out and then close the issue? Go's JPEG implementation is broken. I've asked the experts as you can see.

[lastzero]

Hope Brad can help ✨

[ianlancetaylor]

@lastzero Closing this pull request was a mistake. That mistake has been corrected. Sorry about that.

Go is an open source project. It's likely that Google has a JPEG expert somewhere, but they don't work on the Go standard library. I hope that @shouldend or somebody else will pick up the change and push it forward. It shouldn't be hard. Perhaps you can do it. Thanks.

[fabioleite0]

Any updates??

[jerbob92]

It's a bit unclear to me whether this is actually a bug because Go doesn't handle some edge cases or that files like these are technically corrupt. Can anyone enlighten me?

And is there anything I can do to move this forward? I'd be willing to create tests for this.

[magus0219]

WHY NOT MERGE!!!

[ianlancetaylor]

Go uses Gerritt for code review. See https://go.dev/doc/contribute. Essentially nobody sees comments on a GitHub pull request. Please comment instead on https://go.dev/cl/260837. Thanks.

[jerbob92]

I also made a new one on Gerrit already that has a more complete fix and test https://go.dev/cl/571236