[FFmpeg-cvslog] avformat/utils: Fix potential integer overflow in extract_extradata()

[Michael Niedermayer]

ffmpeg | branch: release/4.0 | Michael Niedermayer <michael at niedermayer.cc> | Thu Sep 27 00:00:26 2018 +0200| [eb495b20e51fb7a5a02ca3004fd5a8ea359592f4] | committer: Michael Niedermayer

avformat/utils: Fix potential integer overflow in extract_extradata()

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 0a41a8bf2945e59db7a0773ebce11a26b95d45b6)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=eb495b20e51fb7a5a02ca3004fd5a8ea359592f4
---

 libavformat/utils.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libavformat/utils.c b/libavformat/utils.c
index c25eab4d49..685fdb9b76 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -3542,7 +3542,9 @@ static int extract_extradata(AVStream *st, AVPacket *pkt)
                                             &extradata_size);
 
         if (extradata) {
-            i->avctx->extradata = av_mallocz(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
+            av_assert0(!i->avctx->extradata);
+            if ((unsigned)extradata_size < FF_MAX_EXTRADATA_SIZE)
+                i->avctx->extradata = av_mallocz(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
             if (!i->avctx->extradata) {
                 av_packet_unref(pkt_ref);
                 return AVERROR(ENOMEM);