[FFmpeg-devel] [PATCH 2/4] avcodec/evc_parse: Check num_remaining_tiles_in_slice_minus1

[Dawid Kozinski/Multimedia (PLT) /SRPOL/Staff Engineer/Samsung Electronics]

Michael

Could you please apply the following patch

[FFmpeg-devel] [PATCH 2/4] avcodec/evc_parse: Check num_remaining_tiles_in_slice_minus1
https://patchwork.ffmpeg.org/project/ffmpeg/patch/20231004225921.30287-2-michael@niedermayer.cc/ 

Dawid

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Michael Niedermayer
> Sent: piątek, 27 października 2023 21:43
> To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH 2/4] avcodec/evc_parse: Check
> num_remaining_tiles_in_slice_minus1
> 
> On Fri, Oct 27, 2023 at 10:07:38AM +0200, Dawid Kozinski/Multimedia (PLT)
> /SRPOL/Staff Engineer/Samsung Electronics wrote:
> >
> >
> >
> >
> > > -----Original Message-----
> > > From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> > > Michael Niedermayer
> > > Sent: czwartek, 5 października 2023 00:59
> > > To: FFmpeg development discussions and patches
> > > <ffmpeg-devel at ffmpeg.org>
> > > Subject: [FFmpeg-devel] [PATCH 2/4] avcodec/evc_parse: Check
> > > num_remaining_tiles_in_slice_minus1
> > >
> > > Fixes: out of array access
> > > Fixes: 62467/clusterfuzz-testcase-minimized-
> > > ffmpeg_BSF_EVC_FRAME_MERGE_fuzzer-6092990982258688
> > >
> > > Found-by: continuous fuzzing process
> > > https://protect2.fireeye.com/v1/url?k=10fdc12a-701f5c77-10fc4a65-
> > > 000babd9f1ba-c93ee30773aca891&q=1&e=409cddd0-bda7-445c-b76b-
> > > 1caf069ec3f8&u=https%3A%2F%2Fgithub.com%2Fgoogle%2Foss-
> > > fuzz%2Ftree%2Fmaster%2Fprojects%2Fffmpeg
> > > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > > ---
> > >  libavcodec/evc_parse.c | 8 ++++++--
> > >  1 file changed, 6 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c index
> > > bd3a4416f2d..5ab33166cf3 100644
> > > --- a/libavcodec/evc_parse.c
> > > +++ b/libavcodec/evc_parse.c
> > > @@ -58,8 +58,12 @@ int ff_evc_parse_slice_header(GetBitContext *gb,
> > > EVCParserSliceHeader *sh,
> > >          if (!sh->arbitrary_slice_flag)
> > >              sh->last_tile_id = get_bits(gb, pps->tile_id_len_minus1 + 1);
> > >          else {
> > > -            sh->num_remaining_tiles_in_slice_minus1 =
> > get_ue_golomb_long(gb);
> > > -            num_tiles_in_slice = sh->num_remaining_tiles_in_slice_minus1
> > + 2;
> > > +            unsigned num_remaining_tiles_in_slice_minus1 =
> > > get_ue_golomb_long(gb);
> > > +            if (num_remaining_tiles_in_slice_minus1 >
> > > + EVC_MAX_TILE_ROWS *
> > > EVC_MAX_TILE_COLUMNS - 2)
> > > +                return AVERROR_INVALIDDATA;
> > > +
> > > +            num_tiles_in_slice = num_remaining_tiles_in_slice_minus1 + 2;
> > > +            sh->num_remaining_tiles_in_slice_minus1 =
> > > + num_remaining_tiles_in_slice_minus1;
> > >              for (int i = 0; i < num_tiles_in_slice - 1; ++i)
> > >                  sh->delta_tile_id_minus1[i] = get_ue_golomb_long(gb);
> > >          }
> > > --
> > > 2.17.1
> > >
> >
> > Reviewed and tested. It can be merged.
> 
> will apply
> 
> thx
> 
> [...]
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
> 
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