| Message ID | 20190721232528.8923-2-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
On 22.07.2019, at 01:25, Michael Niedermayer <michael@niedermayer.cc> wrote: > Fixes: Timeout (2min -> 100ms) > Fixes: 15366/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_THEORA_fuzzer-5737849938247680 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/vp3.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c > index a6f759ebf5..8a165c1275 100644 > --- a/libavcodec/vp3.c > +++ b/libavcodec/vp3.c > @@ -2957,6 +2957,8 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) > s->theora_header = 0; > s->theora = get_bits_long(gb, 24); > av_log(avctx, AV_LOG_DEBUG, "Theora bitstream version %X\n", s->theora); > + if (!s->theora) > + return AVERROR_INVALIDDATA; That seems rather strict, a 1-bit error in this field and we don't even try? Maybe set to 1 instead with a request for sample?
On Mon, Jul 22, 2019 at 07:07:57AM +0200, Reimar Döffinger wrote: > > > On 22.07.2019, at 01:25, Michael Niedermayer <michael@niedermayer.cc> wrote: > > > Fixes: Timeout (2min -> 100ms) > > Fixes: 15366/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_THEORA_fuzzer-5737849938247680 > > > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > > --- > > libavcodec/vp3.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c > > index a6f759ebf5..8a165c1275 100644 > > --- a/libavcodec/vp3.c > > +++ b/libavcodec/vp3.c > > @@ -2957,6 +2957,8 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) > > s->theora_header = 0; > > s->theora = get_bits_long(gb, 24); > > av_log(avctx, AV_LOG_DEBUG, "Theora bitstream version %X\n", s->theora); > > + if (!s->theora) > > + return AVERROR_INVALIDDATA; > > That seems rather strict, a 1-bit error in this field and we don't even try? > Maybe set to 1 instead with a request for sample? ok, will post a new patch [...]
On 24.07.2019, at 14:37, Michael Niedermayer <michael@niedermayer.cc> wrote: > On Mon, Jul 22, 2019 at 07:07:57AM +0200, Reimar Döffinger wrote: >> >> >> On 22.07.2019, at 01:25, Michael Niedermayer <michael@niedermayer.cc> wrote: >> >>> Fixes: Timeout (2min -> 100ms) >>> Fixes: 15366/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_THEORA_fuzzer-5737849938247680 >>> >>> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg >>> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> >>> --- >>> libavcodec/vp3.c | 2 ++ >>> 1 file changed, 2 insertions(+) >>> >>> diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c >>> index a6f759ebf5..8a165c1275 100644 >>> --- a/libavcodec/vp3.c >>> +++ b/libavcodec/vp3.c >>> @@ -2957,6 +2957,8 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) >>> s->theora_header = 0; >>> s->theora = get_bits_long(gb, 24); >>> av_log(avctx, AV_LOG_DEBUG, "Theora bitstream version %X\n", s->theora); >>> + if (!s->theora) >>> + return AVERROR_INVALIDDATA; >> >> That seems rather strict, a 1-bit error in this field and we don't even try? >> Maybe set to 1 instead with a request for sample? > > ok, will post a new patch Thanks. Sorry if it was maybe a bit nitpicky comment, but seemed like doing it a but nicer might be worth the effort.
diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c index a6f759ebf5..8a165c1275 100644 --- a/libavcodec/vp3.c +++ b/libavcodec/vp3.c @@ -2957,6 +2957,8 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb) s->theora_header = 0; s->theora = get_bits_long(gb, 24); av_log(avctx, AV_LOG_DEBUG, "Theora bitstream version %X\n", s->theora); + if (!s->theora) + return AVERROR_INVALIDDATA; /* 3.2.0 aka alpha3 has the same frame orientation as original vp3 * but previous versions have the image flipped relative to vp3 */
Fixes: Timeout (2min -> 100ms) Fixes: 15366/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_THEORA_fuzzer-5737849938247680 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/vp3.c | 2 ++ 1 file changed, 2 insertions(+)