4xm: check if there are bits left in decode_i_block()
authorMichael Niedermayer <michaelni@gmx.at>
Wed, 14 Dec 2011 21:20:39 +0000 (22:20 +0100)
committerMichael Niedermayer <michaelni@gmx.at>
Wed, 14 Dec 2011 21:24:44 +0000 (22:24 +0100)
Fixed Ticket753
Bug Found by: Diana Elena Muscalu

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
libavcodec/4xm.c

index 9350f06..f854f1c 100644 (file)
@@ -459,6 +459,11 @@ static int decode_p_frame(FourXContext *f, const uint8_t *buf, int length){
 static int decode_i_block(FourXContext *f, DCTELEM *block){
     int code, i, j, level, val;
 
+    if(get_bits_left(&f->gb) < 2){
+        av_log(f->avctx, AV_LOG_ERROR, "%d bits left before decode_i_block()\n", get_bits_left(&f->gb));
+        return -1;
+    }
+
     /* DC coef */
     val = get_vlc2(&f->pre_gb, f->pre_vlc.table, ACDC_VLC_BITS, 3);
     if (val>>4){