On Sat, Apr 27, 2024 at 12:14:18PM +0200, Andreas Rheinhardt wrote:
> Michael Niedermayer:
> > Fixes: NULL pointer dereferences
> > Fixes: 68197/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-6382538823106560
> > 
> > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> > ---
> >  libavcodec/hevcdec.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/libavcodec/hevcdec.c b/libavcodec/hevcdec.c
> > index fcfb275f63a..92b0e45eee0 100644
> > --- a/libavcodec/hevcdec.c
> > +++ b/libavcodec/hevcdec.c
> > @@ -1969,13 +1969,13 @@ static void hls_prediction_unit(HEVCLocalContext *lc, int x0, int y0,
> >  
> >      if (current_mv.pred_flag & PF_L0) {
> >          ref0 = refPicList[0].ref[current_mv.ref_idx[0]];
> > -        if (!ref0 || !ref0->frame->data[0])
> > +        if (!ref0 || !ref0->frame || !ref0->frame->data[0])
> >              return;
> >          hevc_await_progress(s, ref0, &current_mv.mv[0], y0, nPbH);
> >      }
> >      if (current_mv.pred_flag & PF_L1) {
> >          ref1 = refPicList[1].ref[current_mv.ref_idx[1]];
> > -        if (!ref1 || !ref1->frame->data[0])
> > +        if (!ref1 || !ref1->frame || !ref1->frame->data[0])
> >              return;
> >          hevc_await_progress(s, ref1, &current_mv.mv[1], y0, nPbH);
> >      }
> 
> Same as with 1/5: Checking for !ref0->frame is enough as HEVCFrame.f is
> set if and only if the HEVCFrame.f->data[0] is set (with the possible

will apply with this simplification

thx

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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