[FFmpeg-cvslog] xan: Prevent NULL dereferences with missing reference frame

[Laurent Aimar]

ffmpeg | branch: master | Laurent Aimar <fenrir at videolan.org> | Tue Sep 27 22:15:32 2011 +0000| [06be075cda0a6ba8bab8f543571b380884f562ac] | committer: Janne Grunau

xan: Prevent NULL dereferences with missing reference frame

Signed-off-by: Janne Grunau <janne-libav at jannau.net>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=06be075cda0a6ba8bab8f543571b380884f562ac
---

 libavcodec/xan.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/libavcodec/xan.c b/libavcodec/xan.c
index f21075c..9e58a77 100644
--- a/libavcodec/xan.c
+++ b/libavcodec/xan.c
@@ -224,6 +224,8 @@ static inline void xan_wc3_copy_pixel_run(XanContext *s,
 
     palette_plane = s->current_frame.data[0];
     prev_palette_plane = s->last_frame.data[0];
+    if (!prev_palette_plane)
+        prev_palette_plane = palette_plane;
     stride = s->current_frame.linesize[0];
     line_inc = stride - width;
     curframe_index = y * stride + x;