[FFmpeg-devel] [PATCH 2/3] avcodec/cbs_h266_syntax_template: Check num_subpic_cols for 0

[Michael Niedermayer]

On Mon, Jul 24, 2023 at 10:54:20PM -0300, James Almer wrote:
> On 7/24/2023 9:46 PM, Michael Niedermayer wrote:
> > Fixes: division by zero
> > Fixes: 60306/clusterfuzz-testcase-minimized-ffmpeg_BSF_TRACE_HEADERS_fuzzer-5538913553612800
> > 
> > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > ---
> >   libavcodec/cbs_h266_syntax_template.c | 2 ++
> >   1 file changed, 2 insertions(+)
> > 
> > diff --git a/libavcodec/cbs_h266_syntax_template.c b/libavcodec/cbs_h266_syntax_template.c
> > index dce0216fbc..18ecf17e3b 100644
> > --- a/libavcodec/cbs_h266_syntax_template.c
> > +++ b/libavcodec/cbs_h266_syntax_template.c
> > @@ -1187,6 +1187,8 @@ static int FUNC(sps)(CodedBitstreamContext *ctx, RWContext *rw,
> >                   } else {
> >                       int num_subpic_cols = tmp_width_val /
> >                                        (current->sps_subpic_width_minus1[0] + 1);
> > +                    if (!num_subpic_cols)
> > +                        return AVERROR_INVALIDDATA;
> >                       infer(sps_subpic_ctu_top_left_x[i],
> >                             (i % num_subpic_cols) *
> >                             (current->sps_subpic_width_minus1[0] + 1));
> 
> Does the following fix it too?

yes, feel free to push this, or i can if you prefer?

thx

[...]
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