From 56cc024220886927350cfc26ee695062ca7ecaf4 Mon Sep 17 00:00:00 2001 From: wm4 Date: Tue, 3 Feb 2015 19:04:12 +0100 Subject: avformat/mpc8: fix hang with fuzzed file This can lead to an endless loop by seeking back a few bytes after each attempted chunk read. Assuming negative sizes are always invalid, this is easy to fix. Other code in this demuxer treats negative sizes as invalid as well. Fixes ticket #4262. Signed-off-by: Michael Niedermayer --- libavformat/mpc8.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'libavformat/mpc8.c') diff --git a/libavformat/mpc8.c b/libavformat/mpc8.c index a15dc25a69..722d0ee05f 100644 --- a/libavformat/mpc8.c +++ b/libavformat/mpc8.c @@ -223,6 +223,10 @@ static int mpc8_read_header(AVFormatContext *s) while(!avio_feof(pb)){ pos = avio_tell(pb); mpc8_get_chunk_header(pb, &tag, &size); + if (size < 0) { + av_log(s, AV_LOG_ERROR, "Invalid chunk length\n"); + return AVERROR_INVALIDDATA; + } if(tag == TAG_STREAMHDR) break; mpc8_handle_chunk(s, tag, pos, size); -- cgit v1.2.3