diff options
| author | Michael Niedermayer <michaelni@gmx.at> | 2013-04-18 19:53:00 +0200 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2013-04-18 20:13:22 +0200 |
| commit | 23daee0dcc57b647b9d62d4c905e94acf0c6b8e0 (patch) | |
| tree | 468bfa5d5975e6907083f942107528aeeebe6e57 | |
| parent | 4c8ce750abaa783109630d41ca7dde5de34f6197 (diff) | |
avcodec/mpegvideo_motion: Check P field references
If a reference is unavailable use a field from the current
picture
Fixes null pointer dereference
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
| -rw-r--r-- | libavcodec/mpegvideo_motion.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/libavcodec/mpegvideo_motion.c b/libavcodec/mpegvideo_motion.c index be1b48d4d8..225e9a637f 100644 --- a/libavcodec/mpegvideo_motion.c +++ b/libavcodec/mpegvideo_motion.c @@ -809,7 +809,8 @@ static av_always_inline void MPV_motion_internal(MpegEncContext *s, s->mv[dir][1][0], s->mv[dir][1][1], 8, mb_y); } } else { - if(s->picture_structure != s->field_select[dir][0] + 1 && s->pict_type != AV_PICTURE_TYPE_B && !s->first_field){ + if( s->picture_structure != s->field_select[dir][0] + 1 && s->pict_type != AV_PICTURE_TYPE_B && !s->first_field + || !ref_picture[0]){ ref_picture = s->current_picture_ptr->f.data; } |