diff options
Diffstat (limited to 'libavcodec/lagarith.c')
| -rw-r--r-- | libavcodec/lagarith.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/libavcodec/lagarith.c b/libavcodec/lagarith.c index 0f4aa89..ba2da2e 100644 --- a/libavcodec/lagarith.c +++ b/libavcodec/lagarith.c @@ -141,6 +141,7 @@ static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb) unsigned prob, cumulative_target; unsigned cumul_prob = 0; unsigned scaled_cumul_prob = 0; + int nnz = 0; rac->prob[0] = 0; rac->prob[257] = UINT_MAX; @@ -164,6 +165,8 @@ static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb) prob = 256 - i; for (j = 0; j < prob; j++) rac->prob[++i] = 0; + }else { + nnz++; } } @@ -172,6 +175,10 @@ static int lag_read_prob_header(lag_rac *rac, GetBitContext *gb) return -1; } + if (nnz == 1 && (show_bits_long(gb, 32) & 0xFFFFFF)) { + return AVERROR_INVALIDDATA; + } + /* Scale probabilities so cumulative probability is an even power of 2. */ scale_factor = av_log2(cumul_prob); |
