[FFmpeg-cvslog] dfa: check for invalid access in decode_wdlt().

[Anton Khirnov]

ffmpeg | branch: release/1.1 | Anton Khirnov <anton at khirnov.net> | Wed Mar 27 18:18:38 2013 +0100| [62f9253781fa4534f10f8dbb0a2fea9377a8c87e] | committer: Reinhard Tartler

dfa: check for invalid access in decode_wdlt().

This can happen when the number of skipped lines is not consistent with
the number of coded lines.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable at libav.org
(cherry picked from commit 3623589edc7b1257bb45aa9e52c9631e133f22b6)

Signed-off-by: Reinhard Tartler <siretart at tauware.de>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=62f9253781fa4534f10f8dbb0a2fea9377a8c87e
---

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

diff --git a/libavcodec/dfa.c b/libavcodec/dfa.c
index 119be70..332a53e 100644
--- a/libavcodec/dfa.c
+++ b/libavcodec/dfa.c
@@ -257,6 +257,8 @@ static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height
             segments = bytestream2_get_le16(gb);
         }
         line_ptr = frame;
+        if (frame_end - frame < width)
+            return AVERROR_INVALIDDATA;
         frame += width;
         y++;
         while (segments--) {