Smack: onlycap limits on CAP_MAC_ADMIN

Smack is integrated with the POSIX capabilities scheme,
using the capabilities CAP_MAC_OVERRIDE and CAP_MAC_ADMIN to
determine if a process is allowed to ignore Smack checks or
change Smack related data respectively. Smack provides an
additional restriction that if an onlycap value is set
by writing to /smack/onlycap only tasks with that Smack
label are allowed to use CAP_MAC_OVERRIDE.

This change adds CAP_MAC_ADMIN as a capability that is affected
by the onlycap mechanism.

Targeted for git://git.gitorious.org/smack-next/kernel.git

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 9f3705e..db14689 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -220,14 +220,9 @@
 	}
 
 	/*
-	 * Return if a specific label has been designated as the
-	 * only one that gets privilege and current does not
-	 * have that label.
+	 * Allow for priviliged to override policy.
 	 */
-	if (smack_onlycap != NULL && smack_onlycap != sp)
-		goto out_audit;
-
-	if (capable(CAP_MAC_OVERRIDE))
+	if (rc != 0 && smack_privileged(CAP_MAC_OVERRIDE))
 		rc = 0;
 
 out_audit: