File bnc619562_CVE-2010-2497.diff of Package freetype2
From 7d3d2cc4fef72c6be9c454b3809c387e12b44cfc Mon Sep 17 00:00:00 2001
From: Werner Lemberg <wl@gnu.org>
Date: Wed, 09 Jun 2010 07:14:09 +0000
Subject: Fix Savannah bug #30082.
* src/cff/cffgload.c (cff_decoder_parse_charstrings)
<cff_op_callothersubr>: Protect against stack underflow.
---
---
src/smooth/ftgrays.c | 35 +++++++++++++++--------------------
1 file changed, 15 insertions(+), 20 deletions(-)
Index: freetype-2.3.9/src/smooth/ftgrays.c
===================================================================
--- freetype-2.3.9.orig/src/smooth/ftgrays.c
+++ freetype-2.3.9/src/smooth/ftgrays.c
@@ -979,45 +979,40 @@
const FT_Vector* control2,
const FT_Vector* to )
{
- TPos dx, dy, da, db;
+ TPos dx, dy;
+ TPos mid_x, mid_y;
int top, level;
int* levels;
FT_Vector* arc;
- dx = DOWNSCALE( ras.x ) + to->x - ( control1->x << 1 );
- if ( dx < 0 )
- dx = -dx;
- dy = DOWNSCALE( ras.y ) + to->y - ( control1->y << 1 );
- if ( dy < 0 )
- dy = -dy;
- if ( dx < dy )
- dx = dy;
- da = dx;
+ /* Calculate midpoint and compare it with start and end. */
+ mid_x = ( DOWNSCALE( ras.x ) + to->x +
+ 3 * ( control1->x + control2->x ) ) / 8;
+ mid_y = ( DOWNSCALE( ras.y ) + to->y +
+ 3 * ( control1->y + control2->y ) ) / 8;
- dx = DOWNSCALE( ras.x ) + to->x - 3 * ( control1->x + control2->x );
+ dx = DOWNSCALE( ras.x ) + to->x - ( mid_x << 1 );
if ( dx < 0 )
dx = -dx;
- dy = DOWNSCALE( ras.y ) + to->y - 3 * ( control1->x + control2->y );
+ dy = DOWNSCALE( ras.y ) + to->y - ( mid_y << 1 );
if ( dy < 0 )
dy = -dy;
if ( dx < dy )
dx = dy;
- db = dx;
+ /* Check whether an approximation with straight lines is sufficient. */
level = 1;
- da = da / ras.cubic_level;
- db = db / ras.conic_level;
- while ( da > 0 || db > 0 )
+ dx = dx / ras.conic_level;
+ while ( dx > 0 )
{
- da >>= 2;
- db >>= 3;
+ dx >>= 3;
level++;
}
if ( level <= 1 )
{
- TPos to_x, to_y, mid_x, mid_y;
+ TPos to_x, to_y;
to_x = UPSCALE( to->x );
@@ -1076,7 +1071,7 @@
Draw:
{
- TPos to_x, to_y, mid_x, mid_y;
+ TPos to_x, to_y;
to_x = arc[0].x;