[FFmpeg-devel] [PATCH 3/4] avcodec/dxv: Check op_offset in both directions

[Michael Niedermayer]

On Fri, Jul 19, 2019 at 09:53:34PM +0200, Michael Niedermayer wrote:
> On Fri, Jul 19, 2019 at 03:36:43PM +0200, Paul B Mahol wrote:
> > On 7/19/19, Michael Niedermayer <michael at niedermayer.cc> wrote:
> > > On Thu, Jun 27, 2019 at 09:32:44AM +0200, Paul B Mahol wrote:
> > >> On 6/27/19, Michael Niedermayer <michael at niedermayer.cc> wrote:
> > >> > Fixes: signed integer overflow: 61 + 2147483647 cannot be represented
> > >> > in
> > >> > type 'int'
> > >> > Fixes:
> > >> > 15311/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DXV_fuzzer-5742552826773504
> > >> >
> > >> > 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/dxv.c | 2 +-
> > >> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >> >
> > >> > diff --git a/libavcodec/dxv.c b/libavcodec/dxv.c
> > >> > index 5fd1844094..3506775560 100644
> > >> > --- a/libavcodec/dxv.c
> > >> > +++ b/libavcodec/dxv.c
> > >> > @@ -745,7 +745,7 @@ static int dxv_decompress_cocg(DXVContext *ctx,
> > >> > GetByteContext *gb,
> > >> >      int skip0, skip1, oi0 = 0, oi1 = 0;
> > >> >      int ret, state0 = 0, state1 = 0;
> > >> >
> > >> > -    if (op_offset < 12)
> > >> > +    if (op_offset < 12 || op_offset - 12 >
> > >> > bytestream2_get_bytes_left(gb))
> > >> >          return AVERROR_INVALIDDATA;
> > >> >
> > >> >      dst = tex_data;
> > >> > --
> > >> > 2.22.0
> > >> >
> > >> > _______________________________________________
> > >> > ffmpeg-devel mailing list
> > >> > ffmpeg-devel at ffmpeg.org
> > >> > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> > >> >
> > >> > To unsubscribe, visit link above, or email
> > >> > ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
> > >>
> > >> Make sure this does not break any files.
> > >
> > > Do you have any specific files i should test ?
> > >
> > > I of course cannot test every file on earth ...
> > 
> > I'm on vacation, so when I get back I will give you some files.
> 
> ok, ill wait, no hurry, enjoy your vacation!

ping, this issue is reaching its deadline, so i would like to
fix it 

Thanks

[...]


-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

When you are offended at any man's fault, turn to yourself and study your
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