From 6ba44b91e37622ef8c146d8f2ac92d708a18ed34 Mon Sep 17 00:00:00 2001
From: Matthieu Herrb <matthieu.herrb@laas.fr>
Date: Mon, 17 Oct 2011 22:26:12 +0200
Subject: [PATCH] Fix CVE-2011-4028: File disclosure vulnerability.

use O_NOFOLLOW to open the existing lock file, so symbolic links
aren't followed, thus avoid revealing if it point to an existing
file.

Signed-off-by: Matthieu Herrb <matthieu.herrb@laas.fr>
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
---
 os/utils.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/os/utils.c b/os/utils.c
index e8ecb7193..fe4925497 100644
--- a/os/utils.c
+++ b/os/utils.c
@@ -318,7 +318,7 @@ LockServer(void)
       /*
        * Read the pid from the existing file
        */
-      lfd = open(LockFile, O_RDONLY);
+      lfd = open(LockFile, O_RDONLY|O_NOFOLLOW);
       if (lfd < 0) {
         unlink(tmp);
         FatalError("Can't read lock file %s\n", LockFile);