| Message ID | 20190808232350.16076-2-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
Are those values even acceptable according to spec? Shouldn't 16k*16K be the maximum allowed? On Fri, Aug 9, 2019, at 01:26, Michael Niedermayer wrote: > Fixes: signed integer overflow: 393215 * 14594 cannot be represented in > type 'int' > Fixes: > 15728/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3IMAGE_fuzzer-5661588893204480 > > Found-by: continuous fuzzing process > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/vc1.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c > index e102b931d8..0790eb160e 100644 > --- a/libavcodec/vc1.c > +++ b/libavcodec/vc1.c > @@ -453,8 +453,8 @@ static int decode_sequence_header_adv(VC1Context > *v, GetBitContext *gb) > } else { > av_reduce(&v->s.avctx->sample_aspect_ratio.num, > &v->s.avctx->sample_aspect_ratio.den, > - v->s.avctx->height * w, > - v->s.avctx->width * h, > + v->s.avctx->height * (int64_t)w, > + v->s.avctx->width * (int64_t)h, > 1 << 30); > } > ff_set_sar(v->s.avctx, v->s.avctx->sample_aspect_ratio); > -- > 2.22.0 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
On Tue, Aug 13, 2019 at 10:56:03AM +0200, Jean-Baptiste Kempf wrote: > Are those values even acceptable according to spec? Which spec ? SMPTE 421M ? no, i think not wmv3image (which is what the fuzzer tested) iam not sure if we have a spec about it. > Shouldn't 16k*16K be the maximum allowed? I can add a test, ask for a sample and fail instead. I guess being more restrictive on this here is a good thing so ill post a new patch with that Thanks [...]
diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c index e102b931d8..0790eb160e 100644 --- a/libavcodec/vc1.c +++ b/libavcodec/vc1.c @@ -453,8 +453,8 @@ static int decode_sequence_header_adv(VC1Context *v, GetBitContext *gb) } else { av_reduce(&v->s.avctx->sample_aspect_ratio.num, &v->s.avctx->sample_aspect_ratio.den, - v->s.avctx->height * w, - v->s.avctx->width * h, + v->s.avctx->height * (int64_t)w, + v->s.avctx->width * (int64_t)h, 1 << 30); } ff_set_sar(v->s.avctx, v->s.avctx->sample_aspect_ratio);
Fixes: signed integer overflow: 393215 * 14594 cannot be represented in type 'int' Fixes: 15728/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3IMAGE_fuzzer-5661588893204480 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/vc1.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)