indeo4: Check the quantization matrix index

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org

libavcodec/indeo4.c

@@ -359,6 +359,11 @@ static int decode_band_hdr(IVI45DecContext *ctx, IVIBandDesc *band,
                 av_log(avctx, AV_LOG_ERROR, "Custom quant matrix encountered!\n");
                 return AVERROR_INVALIDDATA;
             }
+            if (band->quant_mat >= FF_ARRAY_ELEMS(quant_index_to_tab)) {
+                avpriv_request_sample(avctx, "Quantization matrix %d",
+                                      band->quant_mat);
+                return AVERROR_INVALIDDATA;
+            }
         }
 
         /* decode block huffman codebook */