[INET]: Small possible memory leak in FIB rules

This patch fixes a small memory leak. Default fib rules can be deleted by
the user if the rule does not carry FIB_RULE_PERMANENT flag, f.e. by
	ip rule flush

Such a rule will not be freed as the ref-counter has 2 on start and becomes
clearly unreachable after removal.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index f16839c..a0ada3a 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -49,33 +49,6 @@
 #endif
 };
 
-static struct fib4_rule default_rule = {
-	.common = {
-		.refcnt =	ATOMIC_INIT(2),
-		.pref =		0x7FFF,
-		.table =	RT_TABLE_DEFAULT,
-		.action =	FR_ACT_TO_TBL,
-	},
-};
-
-static struct fib4_rule main_rule = {
-	.common = {
-		.refcnt =	ATOMIC_INIT(2),
-		.pref =		0x7FFE,
-		.table =	RT_TABLE_MAIN,
-		.action =	FR_ACT_TO_TBL,
-	},
-};
-
-static struct fib4_rule local_rule = {
-	.common = {
-		.refcnt =	ATOMIC_INIT(2),
-		.table =	RT_TABLE_LOCAL,
-		.action =	FR_ACT_TO_TBL,
-		.flags =	FIB_RULE_PERMANENT,
-	},
-};
-
 #ifdef CONFIG_NET_CLS_ROUTE
 u32 fib_rules_tclass(struct fib_result *res)
 {
@@ -319,11 +292,27 @@
 	.owner		= THIS_MODULE,
 };
 
+static int __init fib_default_rules_init(void)
+{
+	int err;
+
+	err = fib_default_rule_add(&fib4_rules_ops, 0,
+				   RT_TABLE_LOCAL, FIB_RULE_PERMANENT);
+	if (err < 0)
+		return err;
+	err = fib_default_rule_add(&fib4_rules_ops, 0x7FFE,
+				   RT_TABLE_MAIN, 0);
+	if (err < 0)
+		return err;
+	err = fib_default_rule_add(&fib4_rules_ops, 0x7FFF,
+				   RT_TABLE_DEFAULT, 0);
+	if (err < 0)
+		return err;
+	return 0;
+}
+
 void __init fib4_rules_init(void)
 {
-	list_add_tail(&local_rule.common.list, &fib4_rules_ops.rules_list);
-	list_add_tail(&main_rule.common.list, &fib4_rules_ops.rules_list);
-	list_add_tail(&default_rule.common.list, &fib4_rules_ops.rules_list);
-
+	BUG_ON(fib_default_rules_init());
 	fib_rules_register(&fib4_rules_ops);
 }