On Fri, Sep 11, 2020 at 08:09:48PM +0200, Michael Niedermayer wrote: > On Fri, Sep 11, 2020 at 11:12:33AM +0200, Paul B Mahol wrote: > > On Fri, Sep 11, 2020 at 01:19:59AM +0200, Michael Niedermayer wrote: > > > Fixes: index -1 out of bounds for type 'const uint8_t [6][16]' > > > Fixes: out of array read > > > Fixes: shift exponent -21 is negative > > > Fixes: > > > 25422/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MOBICLIP_fuzzer-5748258226569216 > > > Fixes: shift exponent 8039082 is too large for 32-bit type 'int' > > > Fixes: > > > 25430/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MOBICLIP_fuzzer-5698567770210304 > > > > > > Found-by: continuous fuzzing process > > > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > > > Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > > > --- > > > libavcodec/mobiclip.c | 6 +++++- > > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > > > diff --git a/libavcodec/mobiclip.c b/libavcodec/mobiclip.c > > > index d147eddbae..13f0edc89d 100644 > > > --- a/libavcodec/mobiclip.c > > > +++ b/libavcodec/mobiclip.c > > > @@ -1323,6 +1323,10 @@ static int mobiclip_decode(AVCodecContext *avctx, > > > void *data, > > > } > > > } else { > > > MotionXY *motion = s->motion; > > > + int quantizer = s->quantizer + get_se_golomb(gb); > > > + > > > + if (quantizer < 12 || quantizer > 161) > > > > From where this numbers come? > > It comes from the implementation > qtab is int and will overflow beyond 161
ok then. > > and below 12 the shift will be negative here: > s->qtab[1][i] = quant8x8_tab[qx][i] << (qy - 2); > > > > I think this is too aggressive. > > > [...] > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > Many that live deserve death. And some that die deserve life. Can you give > it to them? Then do not be too eager to deal out death in judgement. For > even the very wise cannot see all ends. -- Gandalf > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
