[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>

1 files changed, 20 insertions, 31 deletions

diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index f16839c6a721..a0ada3a8d8dd 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -49,33 +49,6 @@ struct fib4_rule
 #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 @@ static struct fib_rules_ops fib4_rules_ops = {
         .owner          = THIS_MODULE,
 };
 
-void __init fib4_rules_init(void)
+static int __init fib_default_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);
+        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)
+{
+        BUG_ON(fib_default_rules_init());
         fib_rules_register(&fib4_rules_ops);
 }