From 75a0e067bd51a93441eda2d55e0ef16d7ad919a1 Mon Sep 17 00:00:00 2001
From: Adam Jackson <ajax@redhat.com>
Date: Tue, 17 Aug 2010 15:13:32 -0400
Subject: [PATCH] fb: Fix overflow computation in lines/arcs/polys/glyphs (#11503)

We can overflow 15-bit coordinates once we account for drawable offset,
so, let's not do that.

Signed-off-by: Adam Jackson <ajax@redhat.com>
---
 fb/fbbits.h |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/fb/fbbits.h b/fb/fbbits.h
index 8bf1a02..9d78603 100644
--- a/fb/fbbits.h
+++ b/fb/fbbits.h
@@ -25,7 +25,9 @@
  * underlying datatypes instead of masks
  */
 
-#define isClipped(c,ul,lr)  ((((c) - (ul)) | ((lr) - (c))) & 0x80008000)
+#define isClipped(c, ul, lr) \
+    ((intToX(c) < intToX(ul)) || (intToX(c) > intToX(lr)) || \
+     (intToY(c) < intToY(ul)) || (intToY(c) > intToY(lr)))
 
 #ifdef HAVE_DIX_CONFIG_H
 #include <dix-config.h>
-- 
1.7.2