[FFmpeg-cvslog] avcodec/movtextdec: Fix potential integer overflow

[Michael Niedermayer]

ffmpeg | branch: release/3.1 | Michael Niedermayer <michael at niedermayer.cc> | Tue Nov 15 14:46:16 2016 +0100| [04310c11aa3967156ef1db9f142e459109b734d6] | committer: Michael Niedermayer

avcodec/movtextdec: Fix potential integer overflow

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 6ea27157682200e5f78cadcabdb009eccd9dd9b1)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=04310c11aa3967156ef1db9f142e459109b734d6
---

 libavcodec/movtextdec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/movtextdec.c b/libavcodec/movtextdec.c
index a33fff7..923e582 100644
--- a/libavcodec/movtextdec.c
+++ b/libavcodec/movtextdec.c
@@ -485,7 +485,7 @@ static int mov_text_decode_frame(AVCodecContext *avctx,
                 m->size_var = 8;
             //size_var is equal to 8 or 16 depending on the size of box
 
-            if (m->tracksize + tsmb_size > avpkt->size)
+            if (tsmb_size > avpkt->size - m->tracksize)
                 break;
 
             for (size_t i = 0; i < box_count; i++) {