diff options
| author | Reinhard Tartler <siretart@tauware.de> | 2011-12-04 10:10:33 +0100 |
|---|---|---|
| committer | Reinhard Tartler <siretart@tauware.de> | 2011-12-23 15:42:24 +0100 |
| commit | 8b94df0f2047e9728cb872adc9e64557b7a5152f (patch) | |
| tree | 99ef2ecef821964ed78a76f5e458b478ef269a34 | |
| parent | 6e24b9488e67849a28e64a8056e05f83cf439229 (diff) | |
| download | ffmpeg-8b94df0f2047e9728cb872adc9e64557b7a5152f.tar.gz | |
vp3dec: Check coefficient index in vp3_dequant()
Based on a patch by Michael Niedermayer <michaelni@gmx.at>
Fixes NGS00145, CVE-2011-4352
Found-by: Phillip Langlois
Signed-off-by: Reinhard Tartler <siretart@tauware.de>
| -rw-r--r-- | libavcodec/vp3.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c index 51ab048ac0..f44d084dbd 100644 --- a/libavcodec/vp3.c +++ b/libavcodec/vp3.c @@ -1363,6 +1363,10 @@ static inline int vp3_dequant(Vp3DecodeContext *s, Vp3Fragment *frag, case 1: // zero run s->dct_tokens[plane][i]++; i += (token >> 2) & 0x7f; + if (i > 63) { + av_log(s->avctx, AV_LOG_ERROR, "Coefficient index overflow\n"); + return i; + } block[perm[i]] = (token >> 9) * dequantizer[perm[i]]; i++; break; @@ -1566,7 +1570,10 @@ static void render_slice(Vp3DecodeContext *s, int slice) /* invert DCT and place (or add) in final output */ if (s->all_fragments[i].coding_method == MODE_INTRA) { - vp3_dequant(s, s->all_fragments + i, plane, 0, block); + int index; + index = vp3_dequant(s, s->all_fragments + i, plane, 0, block); + if (index > 63) + continue; if(s->avctx->idct_algo!=FF_IDCT_VP3) block[0] += 128<<3; s->dsp.idct_put( @@ -1574,7 +1581,10 @@ static void render_slice(Vp3DecodeContext *s, int slice) stride, block); } else { - if (vp3_dequant(s, s->all_fragments + i, plane, 1, block)) { + int index = vp3_dequant(s, s->all_fragments + i, plane, 1, block); + if (index > 63) + continue; + if (index > 0) { s->dsp.idct_add( output_plane + first_pixel, stride, |