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| author | Michael Niedermayer <michael@niedermayer.cc> | 2019-06-15 23:28:25 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2019-11-11 20:18:46 +0100 |
| commit | 89c3387e3077cfa528fc8446e0ddee3c8d78a6c9 (patch) | |
| tree | ad4578fc640d21538c6c9e6e2dc9cdf71edf6058 | |
| parent | 2f4b8dab94d5437f3fc6ff6eded97feafb42284d (diff) | |
| download | ffmpeg-89c3387e3077cfa528fc8446e0ddee3c8d78a6c9.tar.gz | |
avcodec/vc1_block: Check for vlc error in vc1_decode_ac_coeff()
Fixes: index -1 out of bounds for type 'const uint8_t [185][2]'
Fixes: 15250/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3IMAGE_fuzzer-5648992869810176
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 79204a1fc8f1988f7d7e6cae2c3b68f513444d38)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavcodec/vc1_block.c | 34 |
1 files changed, 26 insertions, 8 deletions
diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c index b06ee9fce7..45760cc6ee 100644 --- a/libavcodec/vc1_block.c +++ b/libavcodec/vc1_block.c @@ -489,13 +489,15 @@ static inline int vc1_coded_block_pred(MpegEncContext * s, int n, * @param codingset set of VLC to decode data * @see 8.1.3.4 */ -static void vc1_decode_ac_coeff(VC1Context *v, int *last, int *skip, +static int vc1_decode_ac_coeff(VC1Context *v, int *last, int *skip, int *value, int codingset) { GetBitContext *gb = &v->s.gb; int index, run, level, lst, sign; index = get_vlc2(gb, ff_vc1_ac_coeff_table[codingset].table, AC_VLC_BITS, 3); + if (index < 0) + return index; if (index != ff_vc1_ac_sizes[codingset] - 1) { run = vc1_index_decode_table[codingset][index][0]; level = vc1_index_decode_table[codingset][index][1]; @@ -541,6 +543,8 @@ static void vc1_decode_ac_coeff(VC1Context *v, int *last, int *skip, *last = lst; *skip = run; *value = (level ^ -sign) + sign; + + return 0; } /** Decode intra block in intra frames - should be faster than decode_intra_block @@ -620,7 +624,9 @@ static int vc1_decode_i_block(VC1Context *v, int16_t block[64], int n, zz_table = v->zz_8x8[1]; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + if (ret < 0) + return ret; i += skip; if (i > 63) break; @@ -792,7 +798,9 @@ static int vc1_decode_i_block_adv(VC1Context *v, int16_t block[64], int n, } while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + if (ret < 0) + return ret; i += skip; if (i > 63) break; @@ -972,7 +980,9 @@ static int vc1_decode_intra_block(VC1Context *v, int16_t block[64], int n, int k; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, codingset); + if (ret < 0) + return ret; i += skip; if (i > 63) break; @@ -1135,7 +1145,9 @@ static int vc1_decode_p_block(VC1Context *v, int16_t block[64], int n, i = 0; last = 0; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + if (ret < 0) + return ret; i += skip; if (i > 63) break; @@ -1163,7 +1175,9 @@ static int vc1_decode_p_block(VC1Context *v, int16_t block[64], int n, i = 0; off = (j & 1) * 4 + (j & 2) * 16; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + if (ret < 0) + return ret; i += skip; if (i > 15) break; @@ -1190,7 +1204,9 @@ static int vc1_decode_p_block(VC1Context *v, int16_t block[64], int n, i = 0; off = j * 32; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + if (ret < 0) + return ret; i += skip; if (i > 31) break; @@ -1217,7 +1233,9 @@ static int vc1_decode_p_block(VC1Context *v, int16_t block[64], int n, i = 0; off = j * 4; while (!last) { - vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + int ret = vc1_decode_ac_coeff(v, &last, &skip, &value, v->codingset2); + if (ret < 0) + return ret; i += skip; if (i > 31) break; |