Fix cmd_pos bounds check to avoid the overflow case.

Originally committed as revision 19640 to svn://svn.ffmpeg.org/ffmpeg/trunk
16 years ago · ffbe087b58
parent 84c1b149b2
commit ffbe087b58
1 changed files with 1 additions and 1 deletions
--- a/libavcodec/dvdsubdec.c
+++ b/libavcodec/dvdsubdec.c
@ -191,7 +191,7 @@ static int decode_dvd_subtitles(AVSubtitle *sub_header,

    cmd_pos = READ_OFFSET(buf + cmd_pos);

-    while ((cmd_pos + 2 + offset_size) < buf_size) {
+    while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {
        date = AV_RB16(buf + cmd_pos);
        next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
        dprintf(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",