On 04.01.2016 16:29, Thilo Borgmann wrote: > Am 04.01.16 um 16:18 schrieb Andreas Cadhalpun: >> Supporting this would require re-initialization to change buffer sizes. >> >> This fixes out of bounds reads. > > Can you upload a sample for this?
Unfortunately (or fortunately?) the sample doesn't trigger this problem when using ffmpeg, it only happens with the simple program I use for fuzz testing. I tracked down the difference: My simple program tries to test a specific codec given on the command line (like the '-c' option of ffmpeg). So it iterates over all streams and uses the stream with a matching codec. However, if none is found it forces the codec given on the command line for the first stream. The difference to ffmpeg is that the latter calls avformat_find_stream_info after forcing the codec, while my simple program did that beforehand. Apparently the API isn't compatible with that as it now used the ac3 parser together with the als decoder, which didn't work out well... I find this a bit strange since avformat_find_stream_info could even find new streams, whose codecs can't be changed, it seems. Better documentation of this would be good. On 04.01.2016 18:31, Derek Buitenhuis wrote: > On 1/4/2016 3:18 PM, Andreas Cadhalpun wrote: >> Supporting this would require re-initialization to change buffer sizes. > > I may be mistaken, but don't we already support some codecs which do > this, properly? Probably, but that wouldn't have mattered for preventing out-of-bounds reads. Anyway, consider this patch dropped. Best regards, Andreas _______________________________________________ ffmpeg-devel mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
