From: Ronald S. Bultje <rbultje@google.com>
Date: Sat, 26 Jan 2013 00:03:15 +0000 (-0800)
Subject: Fix overread/write reported by valgrind if (mb_cols) & 3 != 0.
X-Git-Tag: v1.3.0~1151^2~227^2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9dc9f07fb8a1452fb123d280741bfbc6469a6ec1;p=libvpx

Fix overread/write reported by valgrind if (mb_cols) & 3 != 0.

We'd backup and restore all cols for a 64x64 SB, but the array wouldn't
be big enough to hold all that data.

Change-Id: Ic68ea721bf07e0b2f3937bd16b0b734bcc743ce1
---

diff --git a/vp9/common/vp9_alloccommon.c b/vp9/common/vp9_alloccommon.c
index f2107d7aa..c4eb9fb7c 100644
--- a/vp9/common/vp9_alloccommon.c
+++ b/vp9/common/vp9_alloccommon.c
@@ -134,7 +134,8 @@ int vp9_alloc_frame_buffers(VP9_COMMON *oci, int width, int height) {
 
   oci->prev_mi = oci->prev_mip + oci->mode_info_stride + 1;
 
-  oci->above_context = vpx_calloc(sizeof(ENTROPY_CONTEXT_PLANES) * oci->mb_cols, 1);
+  oci->above_context =
+    vpx_calloc(sizeof(ENTROPY_CONTEXT_PLANES) * (3 + oci->mb_cols), 1);
 
   if (!oci->above_context) {
     vp9_de_alloc_frame_buffers(oci);