[FFmpeg-devel] [PATCH] avformat/avidec: ensure that palette does not contain the BottomUp info.

[Benoit Fouet]

Considering the palette is located at the end of extradata may be flawed
when the extradata contains the palette followed by the BottomUp field.
When the BottomUp field is present, exclude it from the palette.
Fixes ticket #1304
---
 libavformat/avidec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavformat/avidec.c b/libavformat/avidec.c
index 5b260e2..f7b15b7 100644
--- a/libavformat/avidec.c
+++ b/libavformat/avidec.c
@@ -756,6 +756,10 @@ static int avi_read_header(AVFormatContext *s)
                         pal_size = FFMIN(pal_size, st->codec->extradata_size);
                         pal_src  = st->codec->extradata +
                                    st->codec->extradata_size - pal_size;
+                        /* Exclude the "BottomUp" field from the palette */
+                        if (pal_src - st->codec->extradata >= 9 &&
+                            !memcmp(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9))
+                            pal_src -= 9;
                         for (i = 0; i < pal_size / 4; i++)
                             ast->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i);
                         ast->has_pal = 1;
-- 
2.1.0.127.g0c72b98