[FFmpeg-cvslog] lagarith: pad RGB buffer by 1 byte.

[Ronald S. Bultje]

ffmpeg | branch: release/0.10 | Ronald S. Bultje <rsbultje at gmail.com> | Thu Aug  2 20:46:09 2012 -0700| [2c1d84499bfe06d75e9160b824eeffd9f5587337] | committer: Reinhard Tartler

lagarith: pad RGB buffer by 1 byte.

For left HFYU prediction, we predict from the buffer buf+1 using 8- or
16-byte reads. This means that aligning the buffer by 16 bytes is in
itself not sufficient, because if the width itself is 16- or 8-byte
aligned, the buffer will not be padded, and thus a read of size 16 at
buf+1 will overflow boundaries at the right edge. Padding the buffer by
1 byte is sufficient to not overflow its boundaries.

Fixes bug 342.

(cherry picked from commit 98d0d19208959766a58f13dd6a678d1f765a26ac)

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=2c1d84499bfe06d75e9160b824eeffd9f5587337
---

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

diff --git a/libavcodec/lagarith.c b/libavcodec/lagarith.c
index f04d89b..93e0253 100644
--- a/libavcodec/lagarith.c
+++ b/libavcodec/lagarith.c
@@ -515,7 +515,7 @@ static int lag_decode_frame(AVCodecContext *avctx,
 
         if (!l->rgb_planes) {
             l->rgb_stride = FFALIGN(avctx->width, 16);
-            l->rgb_planes = av_malloc(l->rgb_stride * avctx->height * planes);
+            l->rgb_planes = av_malloc(l->rgb_stride * avctx->height * planes + 1);
             if (!l->rgb_planes) {
                 av_log(avctx, AV_LOG_ERROR, "cannot allocate temporary buffer\n");
                 return AVERROR(ENOMEM);