[FFmpeg-devel] [PATCH] vp9: avoid infinite loop with broken files

[Ronald S. Bultje]

Hi,

On Sat, Jan 10, 2015 at 12:15 PM, wm4 <nfxjfg at googlemail.com> wrote:

> On Sat, 10 Jan 2015 18:03:48 +0100
> Hendrik Leppkes <h.leppkes at gmail.com> wrote:
>
> > On Sat, Jan 10, 2015 at 6:00 PM, wm4 <nfxjfg at googlemail.com> wrote:
> >
> > > With a certain fuzzed file, the parser will always return 0 consumed
> > > bytes, which makes calling code call the parser infinitely. Return the
> > > full packet size on error instead. (Here it would be nice if parsers
> > > could return errors at all.)
> > >
> > > Additionally, _if_ there's some data left, return that too, which might
> > > help with somewhat broken but still somehow playable files.
> > >
> > > Fixes ticket #4242.
> > > ---
> > > There might be a more elegant way to fix this.
> > > Also, not sure if the change *out_size has any worth.
> > >
> >
> > Signaling the out_size would mean it should forward the data to the
> > decoder, if it remains 0 the data is just swallowed. What would make more
> > sense in this case?
>
> I'd argue that it's normal for ffmpeg to play something even if the
> data has been pushed through a blender, so if there's a trivial choice
> between swallowing and returning the data, the latter should be picked.
> But actually, it probably doesn't matter.


I think I agree, although it's hard to say it makes any difference at this
point. So patch is probably fine.

Thanks,
Ronald