electronicarts: check bytes per sample for validity

Prevents division by zero.

libavformat/electronicarts.c

@@ -434,6 +434,11 @@ static int ea_read_header(AVFormatContext *s,
             ea->audio_codec = 0;
             return 1;
         }
+        if (ea->bytes <= 0) {
+            av_log(s, AV_LOG_ERROR, "Invalid number of bytes per sample: %d\n", ea->bytes);
+            ea->audio_codec = CODEC_ID_NONE;
+            return 1;
+        }
 
         /* initialize the audio decoder stream */
         st = avformat_new_stream(s, NULL);