[FFmpeg-cvslog] mpegvideo: dont leave stale pointers in next/last picture

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Sat Jan 12 04:45:21 2013 +0100| [d9226b3717fda04c5cde8f51c4dc85fa735b1909] | committer: Michael Niedermayer

mpegvideo: dont leave stale pointers in next/last picture

Fixes out of array reads

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d9226b3717fda04c5cde8f51c4dc85fa735b1909
---

 libavcodec/mpegvideo.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 4609b0b..4fd8062 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -1496,6 +1496,8 @@ int ff_MPV_frame_start(MpegEncContext *s, AVCodecContext *avctx)
         }
     }
 
+    memset(s->last_picture.f.data, 0, sizeof(s->last_picture.f.data));
+    memset(s->next_picture.f.data, 0, sizeof(s->next_picture.f.data));
     if (s->last_picture_ptr)
         ff_copy_picture(&s->last_picture, s->last_picture_ptr);
     if (s->next_picture_ptr)