On Mon, Nov 14, 2016 at 9:55 PM, Andreas Cadhalpun <andreas.cadhal...@googlemail.com> wrote: > On 14.11.2016 20:54, Anton Khirnov wrote: >> Quoting Andreas Cadhalpun (2016-11-14 20:30:10) >>> On 14.11.2016 00:01, Luca Barbato wrote: >>>> On 13/11/2016 19:23, Andreas Cadhalpun wrote: >>>>> avc->channels can be 0. >>>> >>>> 0 and less than zero shouldn't be an error? >>> >>> Such values should be rejected, wherever they are set. >>> However, ensuring that is a larger change I'm currently >>> working on. >>> Meanwhile, this patch is a trivial fix for the potential >>> security problem that can easily be backported. >> >> channels being zero is perfectly valid, it means the caller does not >> know the channel count and expects the decoder to read it from the >> bitstream. > > In general code this is correct, however if e.g. the matroska demuxer > reads an audio stream which claims to have 0 channels, it should > be rejected as broken. >
Well, not necessarily. Just because the container info is wrong or missing does not mean the stream is undecodable - not all containers have such levels of info after all, or sometimes none (see mpegts). Compressed codecs are often designed to be independent of container info. - Hendrik _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
