Imported Debian patch 2:1.15.1-0ubuntu2.6

[deb_xorg-server.git] / debian / patches / CVE-2014-8xxx / 0005-dix-integer-overflow-in-REQUEST_FIXED_SIZE-CVE-2014-.patch

From 7d4f361a216718fc7333ab805dafdb9e5c85c180 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Wed, 22 Jan 2014 23:44:46 -0800
Subject: [PATCH 05/33] dix: integer overflow in REQUEST_FIXED_SIZE()
 [CVE-2014-8092 4/4]

Force use of 64-bit integers when evaluating data provided by clients
in 32-bit fields which can overflow when added or multiplied during
checks.

Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
---
 include/dix.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/dix.h b/include/dix.h
index 991a3ce..e0c6ed8 100644
--- a/include/dix.h
+++ b/include/dix.h
@@ -76,7 +76,8 @@ SOFTWARE.
 
 #define REQUEST_FIXED_SIZE(req, n)\
     if (((sizeof(req) >> 2) > client->req_len) || \
-        (((sizeof(req) + (n) + 3) >> 2) != client->req_len)) \
+        ((n >> 2) >= client->req_len) || \
+        ((((uint64_t) sizeof(req) + (n) + 3) >> 2) != (uint64_t) client->req_len))  \
          return(BadLength)
 
 #define LEGAL_NEW_RESOURCE(id,client)\
-- 
1.7.9.2