[FFmpeg-devel] [PATCH 10/10] Add av_image_alloc() and use it in avfilter_default_get_video_buffer().

[Stefano Sabatini]

On date Sunday 2010-11-14 01:02:00 +0100, Michael Niedermayer encoded:
> On Tue, Nov 09, 2010 at 11:55:44PM +0100, Stefano Sabatini wrote:
> > On date Saturday 2010-11-06 01:50:35 +0100, Stefano Sabatini encoded:
> > > On date Friday 2010-11-05 15:17:41 +0100, Stefano Sabatini encoded:
> > > > ---
> > > >  libavcore/imgutils.c   |   25 +++++++++++++++++++++++++
> > > >  libavcore/imgutils.h   |   11 +++++++++++
> > > >  libavfilter/defaults.c |   16 ++--------------
> > > >  3 files changed, 38 insertions(+), 14 deletions(-)
> > > 
> > > Update with some fixes.
> > 
> > New update + bonus patch.
> > 
> > BTW I wonder, should we deprecate the avpicture API?
> > -- 
> > FFmpeg = Frenzy Faithless Merciful Pitiless Extensive Guru
> 
> >  libavcore/imgutils.c   |   27 +++++++++++++++++++++++++++
> >  libavcore/imgutils.h   |   11 +++++++++++
> >  libavfilter/defaults.c |   17 +++--------------
> >  3 files changed, 41 insertions(+), 14 deletions(-)
> > 9eba9b12a7f2f0d74e973fc4ca94731405c83007  0004-Implement-av_image_alloc-and-use-it-in.patch
> > From 7b9fc086117b9f4d7b308f070bd322dfd695b240 Mon Sep 17 00:00:00 2001
> > From: Stefano Sabatini <stefano.sabatini-lala at poste.it>
> > Date: Sun, 7 Nov 2010 16:51:50 +0100
> > Subject: [PATCH 4/9] Implement av_image_alloc() and use it in
> >  avfilter_default_get_video_buffer().
> > 
> > ---
> >  libavcore/imgutils.c   |   27 +++++++++++++++++++++++++++
> >  libavcore/imgutils.h   |   11 +++++++++++
> >  libavfilter/defaults.c |   17 +++--------------
> >  3 files changed, 41 insertions(+), 14 deletions(-)
> > 
> > diff --git a/libavcore/imgutils.c b/libavcore/imgutils.c
> > index 554639f..a2c3c7d 100644
> > --- a/libavcore/imgutils.c
> > +++ b/libavcore/imgutils.c
> > @@ -161,6 +161,33 @@ int ff_set_systematic_pal2(uint32_t pal[256], enum PixelFormat pix_fmt)
> >      return 0;
> >  }
> >  
> > +int av_image_alloc(uint8_t *pointers[4], int linesizes[4],
> > +                   int w, int h, enum PixelFormat pix_fmt, int align)
> > +{
> > +    int i, ret;
> > +    uint8_t *buf;
> > +
> > +    if ((ret = av_image_fill_linesizes(linesizes, pix_fmt, w)) < 0)
> > +        return ret;
> > +
> > +    for (i = 0; i < 4; i++)
> > +        linesizes[i] = FFALIGN(linesizes[i], align);
> > +
> > +    if ((ret = av_image_fill_pointers(pointers, pix_fmt, h, NULL, linesizes)) < 0)
> > +        return ret;
> 
> av_image_fill_pointers() does not seem to check w/h being valid and thus may
> be exploitable

Added av_image_check_size() check, I don't know if we should add to
the function params a log_offset and log_ctx, or simply disable
logging in all cases.

Also I see a function:
int av_image_get_size(int linesizes[4], int w, int h, enum PixFmt pix_fmt, int align);

may be useful as well.
-- 
FFmpeg = Fascinating and Faithless Moronic Plastic Excellent Ghost