[FFmpeg-cvslog] avformat/mov: Fix potential integer overflow in mov_read_keys

[Sergey Volk]

ffmpeg | branch: release/3.1 | Sergey Volk <servolk at google.com> | Wed Sep  7 14:05:35 2016 -0700| [7a3dc2f7b6c2fbe62aeed7839e736db395a6f76a] | committer: Michael Niedermayer

avformat/mov: Fix potential integer overflow in mov_read_keys

Actual allocation size is computed as (count + 1)*sizeof(meta_keys), so
we need to check that (count + 1) won't cause overflow.

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 347cb14b7cba7560e53f4434b419b9d8800253e7)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7a3dc2f7b6c2fbe62aeed7839e736db395a6f76a
---

 libavformat/mov.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/mov.c b/libavformat/mov.c
index 7266fd0..dd746b4 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -3243,7 +3243,7 @@ static int mov_read_keys(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 
     avio_skip(pb, 4);
     count = avio_rb32(pb);
-    if (count > UINT_MAX / sizeof(*c->meta_keys)) {
+    if (count > UINT_MAX / sizeof(*c->meta_keys) - 1) {
         av_log(c->fc, AV_LOG_ERROR,
                "The 'keys' atom with the invalid key count: %d\n", count);
         return AVERROR_INVALIDDATA;