From 8e8e3c26b87d78b92d96ba91d58ee59d774ebcb5 Mon Sep 17 00:00:00 2001
From: Nickolai Zeldovich <nickolai@csail.mit.edu>
Date: Sat, 5 Jan 2013 23:45:59 -0500
Subject: [PATCH] libadmin/vos/vosutils.c: mask out sign-extension

Right-shifting a signed int by 24 bits can produce a value outside of
0..0xff due to sign-extension.  As a result, in AddressMatch(), the
first bPattern!=255 check can never succeed.  Fix by masking with 255
before comparison.

Change-Id: Idb0b4c176ff120c7cf0e03a935ebfdca51084bbd
Reviewed-on: http://gerrit.openafs.org/8884
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---
 src/libadmin/vos/vosutils.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/libadmin/vos/vosutils.c b/src/libadmin/vos/vosutils.c
index 191e5f435c..3fcab99890 100644
--- a/src/libadmin/vos/vosutils.c
+++ b/src/libadmin/vos/vosutils.c
@@ -568,8 +568,8 @@ AddressMatch(int addrTest, int addrPattern)
     int bPattern;
 
     /* Test the high byte */
-    bTest = addrTest >> 24;
-    bPattern = addrPattern >> 24;
+    bTest = (addrTest >> 24) & 255;
+    bPattern = (addrPattern >> 24) & 255;
     if ((bTest != bPattern) && (bPattern != 255)) {
 	return FALSE;
     }