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| author | Michael Niedermayer <michael@niedermayer.cc> | 2017-11-15 21:17:15 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2017-12-07 23:38:06 +0100 |
| commit | 77cfc820cfb5a7edad065c91a0f9650f0ce0dc90 (patch) | |
| tree | 44bcb185508731254111620bb2f636b763a54acf | |
| parent | 53715eb13ee1f3197c4a211fdb063a264e17fe0a (diff) | |
| download | ffmpeg-77cfc820cfb5a7edad065c91a0f9650f0ce0dc90.tar.gz | |
avcodec/snowdec: Check intra block dc differences.
Fixes: Timeout
Fixes: 3142/clusterfuzz-testcase-5007853163118592
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit c3b9bbcc6edf2d83fe4857484cfa0839872188c6)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/snowdec.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c index 727e908fb5..a828769610 100644 --- a/libavcodec/snowdec.c +++ b/libavcodec/snowdec.c @@ -183,13 +183,22 @@ static int decode_q_branch(SnowContext *s, int level, int x, int y){ int my_context= av_log2(2*FFABS(left->my - top->my)) + 0*av_log2(2*FFABS(tr->my - top->my)); type= get_rac(&s->c, &s->block_state[1 + left->type + top->type]) ? BLOCK_INTRA : 0; - if(type){ + int ld, cbd, crd; pred_mv(s, &mx, &my, 0, left, top, tr); - l += get_symbol(&s->c, &s->block_state[32], 1); + ld = get_symbol(&s->c, &s->block_state[32], 1); + if (ld < -255 || ld > 255) { + return AVERROR_INVALIDDATA; + } + l += ld; if (s->nb_planes > 2) { - cb+= get_symbol(&s->c, &s->block_state[64], 1); - cr+= get_symbol(&s->c, &s->block_state[96], 1); + cbd = get_symbol(&s->c, &s->block_state[64], 1); + crd = get_symbol(&s->c, &s->block_state[96], 1); + if (cbd < -255 || cbd > 255 || crd < -255 || crd > 255) { + return AVERROR_INVALIDDATA; + } + cb += cbd; + cr += crd; } }else{ if(s->ref_frames > 1) |