[RFC] [PATCH -mm] agp: remove uid comparison as security check

["Serge E. Hallyn" <serue@us.ibm.com>]

>From d4ca1a9749c5b40325ec2db9fcde2f2cbd0e0978 Mon Sep 17 00:00:00 2001
From: serue@us.ibm.com <serue@us.ibm.com>
Date: Wed, 5 Dec 2007 13:55:36 -0800
Subject: [RFC] [PATCH -mm] agp: remove uid comparison as security check

In the face of containers and user namespaces, a uid==0 check for
security is not safe.  Switch to a capability check.

I'm not sure I picked the right capability, but this being AGP
CAP_SYS_RAWIO seemed to make sense.

Signed-off-by: Serge Hallyn <serue@us.ibm.com>
---
 drivers/char/agp/frontend.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/char/agp/frontend.c b/drivers/char/agp/frontend.c
index 9bd5a95..55d7a82 100644
--- a/drivers/char/agp/frontend.c
+++ b/drivers/char/agp/frontend.c
@@ -689,7 +689,7 @@ static int agp_open(struct inode *inode, struct file *file)
 	set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
 	priv->my_pid = current->pid;
 
-	if ((current->uid == 0) || (current->suid == 0)) {
+	if (capable(CAP_SYS_RAWIO)) {
 		/* Root priv, can be controller */
 		set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
 	}
-- 
1.5.1