[FFmpeg-devel] [PATCH] avcodec/ac3dec: Fix shift signedness in mask creation

[Michael Niedermayer]

On Fri, Sep 21, 2018 at 10:41:18AM -0300, James Almer wrote:
> On 9/21/2018 9:30 AM, Michael Niedermayer wrote:
> > Fixes: 9924/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_EAC3_fuzzer-5473421772193792
> > Fixes: left shift of 1 by 63 places cannot be represented in type 'long long'
> > 
> > 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/ac3dec.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
> > index eed8ce5b39..e4d293a2aa 100644
> > --- a/libavcodec/ac3dec.c
> > +++ b/libavcodec/ac3dec.c
> > @@ -1708,7 +1708,7 @@ dependent_frame:
> >                      int i;
> >  
> >                      for (i = 0; i < 64; i++) {
> > -                        if ((1LL << i) & ff_eac3_custom_channel_map_locations[ch][1]) {
> > +                        if ((1ULL << i) & ff_eac3_custom_channel_map_locations[ch][1]) {
> >                              int index = av_get_channel_layout_channel_index(channel_layout,
> >                                                                              1LL << i);
> 
> What about this one?

i think the code is never reached with i==63, but i agree the 2nd one should
be changed too if one is changed, its cleaner and more consistent. i will do 
that

thx

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Everything should be made as simple as possible, but not simpler.
-- Albert Einstein
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20180921/0c5ff01f/attachment.sig>