ffmpeg | branch: master | Michael Niedermayer <michael@niedermayer.cc> | Thu Aug 15 20:15:20 2019 +0200| [fe536b6d9984d40f800a24a84032b99ebc9f680e] | committer: Michael Niedermayer avcodec/vc1_block: Check the return code from vc1_decode_p_block() Fixes: left shift of negative value -1 Fixes: 16424/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3_fuzzer-5656579055026176 Fixes: 16358/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1IMAGE_fuzzer-5714436358144000 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fe536b6d9984d40f80...

libavcodec/vc1_block.c | 37 +++++++++++++++++++++++++++---------- 1 file changed, 27 insertions(+), 10 deletions(-) diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c index 775e3c516b..514206f6d2 100644 --- a/libavcodec/vc1_block.c +++ b/libavcodec/vc1_block.c @@ -1385,6 +1385,8 @@ static int vc1_decode_p_mb(VC1Context *v) pat = vc1_decode_p_block(v, v->block[v->cur_blk_idx][block_map[i]], i, mquant, ttmb, first_block, s->dest[dst_idx] + off, (i & 4) ? s->uvlinesize : s->linesize, CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1; @@ -1488,6 +1490,8 @@ static int vc1_decode_p_mb(VC1Context *v) (i & 4) ? s->uvlinesize : s->linesize, CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1; @@ -1698,6 +1702,8 @@ static int vc1_decode_p_mb_intfr(VC1Context *v) first_block, s->dest[dst_idx] + off, (i & 4) ? s->uvlinesize : (s->linesize << fieldtx), CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1; @@ -1834,6 +1840,8 @@ static int vc1_decode_p_mb_intfi(VC1Context *v) (i & 4) ? s->uvlinesize : s->linesize, CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1; @@ -1853,7 +1861,7 @@ static int vc1_decode_p_mb_intfi(VC1Context *v) /** Decode one B-frame MB (in Main profile) */ -static void vc1_decode_b_mb(VC1Context *v) +static int vc1_decode_b_mb(VC1Context *v) { MpegEncContext *s = &v->s; GetBitContext *gb = &s->gb; @@ -1919,7 +1927,7 @@ static void vc1_decode_b_mb(VC1Context *v) bmvtype = BMV_TYPE_INTERPOLATED; ff_vc1_pred_b_mv(v, dmv_x, dmv_y, direct, bmvtype); vc1_b_mc(v, dmv_x, dmv_y, direct, bmvtype); - return; + return 0; } if (direct) { cbp = get_vlc2(&v->s.gb, v->cbpcy_vlc->table, VC1_CBPCY_P_VLC_BITS, 2); @@ -1936,7 +1944,7 @@ static void vc1_decode_b_mb(VC1Context *v) /* no coded blocks - effectively skipped */ ff_vc1_pred_b_mv(v, dmv_x, dmv_y, direct, bmvtype); vc1_b_mc(v, dmv_x, dmv_y, direct, bmvtype); - return; + return 0; } if (s->mb_intra && !mb_has_coeffs) { GET_MQUANT(); @@ -1951,7 +1959,7 @@ static void vc1_decode_b_mb(VC1Context *v) /* interpolated skipped block */ ff_vc1_pred_b_mv(v, dmv_x, dmv_y, direct, bmvtype); vc1_b_mc(v, dmv_x, dmv_y, direct, bmvtype); - return; + return 0; } } ff_vc1_pred_b_mv(v, dmv_x, dmv_y, direct, bmvtype); @@ -1995,20 +2003,23 @@ static void vc1_decode_b_mb(VC1Context *v) i & 4 ? s->uvlinesize : s->linesize); } else if (val) { - vc1_decode_p_block(v, s->block[i], i, mquant, ttmb, - first_block, s->dest[dst_idx] + off, - (i & 4) ? s->uvlinesize : s->linesize, - CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), NULL); + int pat = vc1_decode_p_block(v, s->block[i], i, mquant, ttmb, + first_block, s->dest[dst_idx] + off, + (i & 4) ? s->uvlinesize : s->linesize, + CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), NULL); + if (pat < 0) + return pat; if (!v->ttmbf && ttmb < 8) ttmb = -1; first_block = 0; } } + return 0; } /** Decode one B-frame MB (in interlaced field B picture) */ -static void vc1_decode_b_mb_intfi(VC1Context *v) +static int vc1_decode_b_mb_intfi(VC1Context *v) { MpegEncContext *s = &v->s; GetBitContext *gb = &s->gb; @@ -2113,7 +2124,7 @@ static void vc1_decode_b_mb_intfi(VC1Context *v) dmv_x[1] = dmv_y[1] = pred_flag[0] = 0; if (!s->next_picture_ptr->field_picture) { av_log(s->avctx, AV_LOG_ERROR, "Mixed field/frame direct mode not supported\n"); - return; + return AVERROR_INVALIDDATA; } } ff_vc1_pred_b_mv_intfi(v, 0, dmv_x, dmv_y, 1, pred_flag); @@ -2158,6 +2169,8 @@ static void vc1_decode_b_mb_intfi(VC1Context *v) first_block, s->dest[dst_idx] + off, (i & 4) ? s->uvlinesize : s->linesize, CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1; @@ -2167,6 +2180,8 @@ static void vc1_decode_b_mb_intfi(VC1Context *v) } v->cbp[s->mb_x] = block_cbp; v->ttblk[s->mb_x] = block_tt; + + return 0; } /** Decode one B-frame MB (in interlaced frame B picture) @@ -2453,6 +2468,8 @@ static int vc1_decode_b_mb_intfr(VC1Context *v) first_block, s->dest[dst_idx] + off, (i & 4) ? s->uvlinesize : (s->linesize << fieldtx), CONFIG_GRAY && (i & 4) && (s->avctx->flags & AV_CODEC_FLAG_GRAY), &block_tt); + if (pat < 0) + return pat; block_cbp |= pat << (i << 2); if (!v->ttmbf && ttmb < 8) ttmb = -1;