From 320b631a99a9f759fd1d5460fd4e285d184b8186 Mon Sep 17 00:00:00 2001 From: Dale Curtis Date: Thu, 30 Aug 2018 15:18:25 -0700 Subject: [PATCH] avformat/mov: Error on too large stsd entry counts. Entries are always at least 8 bytes per the parsing code, so if we see an impossible entry count avoid massive allocations. This is similar to an existing check in mov_read_stsc(). Since ff_mov_read_stsd_entries() does eof checks, an alternative approach could be to clamp the entry count to atom.size / 8. Signed-off-by: Dale Curtis Signed-off-by: Michael Niedermayer --- libavformat/mov.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavformat/mov.c b/libavformat/mov.c index d66f4e338c..d922e0f173 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -2558,7 +2558,8 @@ static int mov_read_stsd(MOVContext *c, AVIOContext *pb, MOVAtom atom) avio_rb24(pb); /* flags */ entries = avio_rb32(pb); - if (entries <= 0) { + /* Each entry contains a size (4 bytes) and format (4 bytes). */ + if (entries <= 0 || entries > atom.size / 8) { av_log(c->fc, AV_LOG_ERROR, "invalid STSD entries %d\n", entries); return AVERROR_INVALIDDATA; }