[CRASH] mythcommflag SIGSEGV in ClassicLogoDetector::DetectEdges()

[Marc Randolph <mrand@…>]

Crash while trying to commflag a (very) corrupt capture. I can upload the stream somewhere if it is desired - otherwise feel free to close this ticket if it is not worth pursuing.

[beirdo]

Is this repeatable? I am thinking of putting in some more null protection, but without a way to test it, I'm not sure if it's worth the effort.

[Marc Randolph <mrand@…>]

It's been four months, but you are lucky - I did manage to find the recording. mythcommflag -v filename still crashes 0.24.1, if that is your question. I can upload the recording somewhere if that is desired.

[beirdo]

Sure, if you could. This would help test the extra protection that I'm thinking of putting in. Few of my files get bad enough to still crash commflagging.

[Marc Randolph <mrand@…>]

Here is a small sample: ​http://www.2shared.com/video/4varxuGf/cut.html I'll try to remember to upload a larger one overnight

[beirdo]

See also #10089

[cpinkham]

If this is still happening, is there any chance you can upload the sample file again? Fixing checks for the null buf pointer won't help solve the underlying problem that we are getting a null pointer from the decoder. We should fix this in the decoder rather than at every point where we touch the buf pointer.

[beirdo]

The file in question was not even watchable. In cases like these, while it would be nice to not crash, it's something inside ffmpeg code that is actually crashing, so without extensive debugging inside their code, it's best to assume this will not get fixed. If your recording is that screwed, delete it and re-record, and live with commflagging crashing on it.