| Message ID | 20190707231805.29267-3-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
On Mon, Jul 08, 2019 at 01:18:04AM +0200, Michael Niedermayer wrote: > Fixes: out of array access > Fixes: 15649/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VORBIS_fuzzer-5729191309344768 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/vorbisdec.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) will apply [...]
On 7/21/19, Michael Niedermayer <michael@niedermayer.cc> wrote: > On Mon, Jul 08, 2019 at 01:18:04AM +0200, Michael Niedermayer wrote: >> Fixes: out of array access >> Fixes: >> 15649/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VORBIS_fuzzer-5729191309344768 >> >> Found-by: continuous fuzzing process >> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg >> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> >> --- >> libavcodec/vorbisdec.c | 6 ++++-- >> 1 file changed, 4 insertions(+), 2 deletions(-) > > will apply Are you sure returning that value is correct approach? Correct value to return is usually INVALIDDATA. > > [...] > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > The educated differ from the uneducated as much as the living from the > dead. -- Aristotle >
On Sun, Jul 21, 2019 at 11:27:44AM +0200, Paul B Mahol wrote: > On 7/21/19, Michael Niedermayer <michael@niedermayer.cc> wrote: > > On Mon, Jul 08, 2019 at 01:18:04AM +0200, Michael Niedermayer wrote: > >> Fixes: out of array access > >> Fixes: > >> 15649/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VORBIS_fuzzer-5729191309344768 > >> > >> Found-by: continuous fuzzing process > >> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > >> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > >> --- > >> libavcodec/vorbisdec.c | 6 ++++-- > >> 1 file changed, 4 insertions(+), 2 deletions(-) > > > > will apply > > Are you sure returning that value is correct approach? > > Correct value to return is usually INVALIDDATA. the only call of this function i see does not use the value if it is negative and uses INVALIDDATA instead. ret = floor->decode(vc, &floor->data, floor_ptr[i]); if (ret < 0) { av_log(vc->avctx, AV_LOG_ERROR, "Invalid codebook in vorbis_floor_decode.\n"); return AVERROR_INVALIDDATA; } but ill replace the code in this patch by an explicit AVERROR_INVALIDDATA before pushing Thanks [...]
diff --git a/libavcodec/vorbisdec.c b/libavcodec/vorbisdec.c index 7f2d27d1a2..d6c6a56e0c 100644 --- a/libavcodec/vorbisdec.c +++ b/libavcodec/vorbisdec.c @@ -1128,8 +1128,10 @@ static int vorbis_floor0_decode(vorbis_context *vc, ff_dlog(NULL, "floor0 dec: maximum depth: %d\n", codebook.maxdepth); /* read temp vector */ vec_off = get_vlc2(&vc->gb, codebook.vlc.table, - codebook.nb_bits, codebook.maxdepth) - * codebook.dimensions; + codebook.nb_bits, codebook.maxdepth); + if (vec_off < 0) + return vec_off; + vec_off *= codebook.dimensions; ff_dlog(NULL, "floor0 dec: vector offset: %d\n", vec_off); /* copy each vector component and add last to it */ for (idx = 0; idx < codebook.dimensions; ++idx)
Fixes: out of array access Fixes: 15649/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VORBIS_fuzzer-5729191309344768 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/vorbisdec.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)