[FFmpeg-cvslog] avcodec/mpegvideo: fix null pointer dereference

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Tue Apr 29 14:50:46 2014 +0200| [6a0b5e34763c14a1e35e767f374ffb98fa64732f] | committer: Michael Niedermayer

avcodec/mpegvideo: fix null pointer dereference

Fixes: 111342.ogm with ffplay
Found-by: Dale Curtis <dalecurtis at google.com>
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6a0b5e34763c14a1e35e767f374ffb98fa64732f
---

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

diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index f2ca9b3..7d9da5c 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -931,7 +931,7 @@ int ff_mpeg_update_thread_context(AVCodecContext *dst,
 #define UPDATE_PICTURE(pic)\
 do {\
     ff_mpeg_unref_picture(s, &s->pic);\
-    if (s1->pic.f->buf[0])\
+    if (s1->pic.f && s1->pic.f->buf[0])\
         ret = ff_mpeg_ref_picture(s, &s->pic, &s1->pic);\
     else\
         ret = update_picture_tables(&s->pic, &s1->pic);\