Correctly skip complete INDX chunks, i.e. read the 32-bit header correctly

and if the size is broken (20 bytes, header-only), calculate the expected
size and skip the index entries anyway. See "[PATCH] rmdec.c: correctly
skip indexes" thread.

Originally committed as revision 17924 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Ronald S. Bultje 2009-03-10 12:55:29 +00:00
parent 5e622c401f
commit b5b9ff2a1f

View File

@ -440,7 +440,19 @@ static int sync(AVFormatContext *s, int64_t *timestamp, int *flags, int *stream_
state= (state<<8) + get_byte(pb);
if(state == MKBETAG('I', 'N', 'D', 'X')){
len = get_be16(pb) - 6;
int n_pkts, expected_len;
len = get_be32(pb);
url_fskip(pb, 2);
n_pkts = get_be32(pb);
expected_len = 20 + n_pkts * 14;
if (len == 20)
/* some files don't add index entries to chunk size... */
len = expected_len;
else if (len != expected_len)
av_log(s, AV_LOG_WARNING,
"Index size %d (%d pkts) is wrong, should be %d.\n",
len, n_pkts, expected_len);
len -= 14; // we already read part of the index header
if(len<0)
continue;
goto skip;