| Message ID | 20201002125915.17281-2-michael@niedermayer.cc |
|---|---|
| State | Accepted |
| Commit | 42ded4d1e6fb0086a235dc584118414ae2bf30c9 |
| Headers | show |
| Series | [FFmpeg-devel,1/3] avcodec/dxtory: Fix negative stride shift in dx2_decode_slice_420() | expand |
| Context | Check | Description |
|---|---|---|
| andriy/default | pending | |
| andriy/make | success | Make finished |
| andriy/make_fate | success | Make fate finished |
Michael Niedermayer: > Fixes: out of array access > Fixes: 26047/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SMACKER_fuzzer-5083031667474432 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/smacker.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c > index 813eb862c0..6b1faec09e 100644 > --- a/libavcodec/smacker.c > +++ b/libavcodec/smacker.c > @@ -448,6 +448,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, > case SMK_BLK_FULL: > mode = 0; > if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes > + if (get_bits_left(&gb) < 1) > + return AVERROR_INVALIDDATA; > if(get_bits1(&gb)) mode = 1; > else if(get_bits1(&gb)) mode = 2; > } > LGTM. (This is a file in which the type and the full tree consists of only one entry (so that smk_get_code() never checks for overreads), isn't it? I have to admit to have overlooked this edge case.) - Andreas
On Mon, Oct 05, 2020 at 03:24:08AM +0200, Andreas Rheinhardt wrote: > Michael Niedermayer: > > Fixes: out of array access > > Fixes: 26047/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SMACKER_fuzzer-5083031667474432 > > > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > > --- > > libavcodec/smacker.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c > > index 813eb862c0..6b1faec09e 100644 > > --- a/libavcodec/smacker.c > > +++ b/libavcodec/smacker.c > > @@ -448,6 +448,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, > > case SMK_BLK_FULL: > > mode = 0; > > if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes > > + if (get_bits_left(&gb) < 1) > > + return AVERROR_INVALIDDATA; > > if(get_bits1(&gb)) mode = 1; > > else if(get_bits1(&gb)) mode = 2; > > } > > > LGTM. will apply > (This is a file in which the type and the full tree consists of only one > entry (so that smk_get_code() never checks for overreads), isn't it? I > have to admit to have overlooked this edge case.) possibly so, id have to recheck thx [...]
diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c index 813eb862c0..6b1faec09e 100644 --- a/libavcodec/smacker.c +++ b/libavcodec/smacker.c @@ -448,6 +448,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, case SMK_BLK_FULL: mode = 0; if(avctx->codec_tag == MKTAG('S', 'M', 'K', '4')) { // In case of Smacker v4 we have three modes + if (get_bits_left(&gb) < 1) + return AVERROR_INVALIDDATA; if(get_bits1(&gb)) mode = 1; else if(get_bits1(&gb)) mode = 2; }
Fixes: out of array access Fixes: 26047/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SMACKER_fuzzer-5083031667474432 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/smacker.c | 2 ++ 1 file changed, 2 insertions(+)