Revert "UBUNTU: SAUCE: apparmor: fix label leak when new label is unused"

This reverts commit 848b65c3.

BugLink: https://bugs.launchpad.net/bugs/1666897Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

security/apparmor/label.c

@@ -308,8 +308,6 @@ int aa_vec_unique(struct aa_profile **vec, int n, int flags)
 
 static void label_destroy(struct aa_label *label)
 {
-	struct aa_label *tmp;
-
 	AA_BUG(!label);
 
 	if (label_is_stale(label))
@@ -331,11 +329,6 @@ static void label_destroy(struct aa_label *label)
 		rcu_assign_pointer(label->proxy->label, NULL);
 
 	aa_free_sid(label->sid);
-
-	tmp = rcu_dereference_protected(label->proxy->label, true);
-	if (tmp == label)
-		rcu_assign_pointer(label->proxy->label, NULL);
-
 	aa_put_proxy(label->proxy);
 	label->proxy = (struct aa_proxy *) PROXY_POISON + 1;
 }
@@ -387,15 +380,6 @@ void aa_label_kref(struct kref *kref)
 	call_rcu(&label->rcu, label_free_rcu);
 }
 
-static void label_free_or_put_new(struct aa_label *label, struct aa_label *new)
-{
-	if (label != new)
-		/* need to free directly to break circular ref with proxy */
-		aa_label_free(new);
-	else
-		aa_put_label(new);
-}
-
 bool aa_label_init(struct aa_label *label, int size)
 {
 	AA_BUG(!label);
@@ -858,7 +842,7 @@ static struct aa_label *vec_create_and_insert_label(struct aa_profile **vec,
 	write_lock_irqsave(&ls->lock, flags);
 	label = __label_insert(ls, new, false);
 	write_unlock_irqrestore(&ls->lock, flags);
-	label_free_or_put_new(label, new);
+	aa_put_label(new);
 
 	return label;
 }
@@ -1257,7 +1241,7 @@ struct aa_label *aa_label_merge(struct aa_label *a, struct aa_label *b,
 			goto out;
 
 		label = label_merge_insert(new, a, b);
-		label_free_or_put_new(label, new);
+		aa_put_label(new);
 	out:
 		aa_put_label(a);
 		aa_put_label(b);
@@ -2058,7 +2042,8 @@ static struct aa_label *__label_update(struct aa_label *label)
 	/* ensure label is removed, and redirected correctly */
 	__label_remove(label, tmp);
 	write_unlock_irqrestore(&ls->lock, flags);
-	label_free_or_put_new(tmp, new);
+
+	aa_put_label(new);
 
 	return tmp;
 }