security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()

This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().

Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <[email protected]>
Reported-by: Reported-by: kbuild test robot <[email protected]>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <[email protected]>
Cc: Micah Morton <[email protected]>
Cc: James Morris <[email protected]>
Cc: "Serge E. Hallyn" <[email protected]>
Cc: <[email protected]>

Author: paulmckrcu

security/safesetid/securityfs.c

@@ -179,8 +179,8 @@ static ssize_t handle_policy_update(struct file *file,
 	 * doesn't currently exist, just use a spinlock for now.
 	 */
 	mutex_lock(&policy_update_lock);
-	rcu_swap_protected(safesetid_setuid_rules, pol,
-			   lockdep_is_held(&policy_update_lock));
+	pol = rcu_replace_pointer(safesetid_setuid_rules, pol,
+				  lockdep_is_held(&policy_update_lock));
 	mutex_unlock(&policy_update_lock);
 	err = len;