avcodec/dcadec: Check nchans

Fixes CID1239110

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit a6a45774d045007f8262cd7c614804390e53122e)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 8 insertions, 0 deletions

diff --git a/libavcodec/dcadec.c b/libavcodec/dcadec.c
index aa583742f5..d4c8676686 100644
--- a/libavcodec/dcadec.c
+++ b/libavcodec/dcadec.c
@@ -571,6 +571,14 @@ static int dca_parse_audio_coding_header(DCAContext *s, int base_channel,
     }
 
     nchans = get_bits(&s->gb, 3) + 1;
+    if (xxch && nchans >= 3) {
+        av_log(s->avctx, AV_LOG_ERROR, "nchans %d is too large\n", nchans);
+        return AVERROR_INVALIDDATA;
+    } else if (nchans + base_channel > DCA_PRIM_CHANNELS_MAX) {
+        av_log(s->avctx, AV_LOG_ERROR, "channel sum %d + %d is too large\n", nchans, base_channel);
+        return AVERROR_INVALIDDATA;
+    }
+
     s->total_channels = nchans + base_channel;
     s->prim_channels  = s->total_channels;