This commit fixes an overflow introduced in a569a7b3 that affected EBML
elements that the Matroska demuxer doesn't want to parse like CRC-32
elements. The return value of avio_skip (the new position on success or
an AVERROR on failure) has been assigned to an integer which meant that
new positions in the range of 2GB to 4GB-1 etc. were considered errors.
Fixes ticket #8001.
Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com>
---
libavformat/matroskadec.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index bc73bfed11..4d7076fa26 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -1259,12 +1259,13 @@ static int ebml_parse_elem(MatroskaDemuxContext
*matroska,
return 1;
default:
if (length) {
+ int64_t res2;
if (ffio_limit(pb, length) != length) {
// ffio_limit emits its own error message,
// so we don't have to.
return AVERROR(EIO);
}
- if ((res = avio_skip(pb, length - 1)) >= 0) {
+ if ((res2 = avio_skip(pb, length - 1)) >= 0) {
// avio_skip might take us past EOF. We check for this
// by skipping only length - 1 bytes, reading a byte and
// checking the error flags. This is done in order to check
@@ -1272,7 +1273,8 @@ static int ebml_parse_elem(MatroskaDemuxContext *matroska,
// no filesize (that ffio_limit relies on) is available.
avio_r8(pb);
res = NEEDS_CHECKING;
- }
+ } else
+ res = res2;
} else
res = 0;
}
--
2.21.0
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
