[IPV4]: Check fib4_rules_init failure.

This adds error paths into both versions of fib4_rules_init
(with/without CONFIG_IP_MULTIPLE_TABLES) and returns error code to the
caller.

Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 27 insertions, 5 deletions

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index ac6238a3b0fd..1bb956b3be28 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -59,12 +59,24 @@ struct fib_table *ip_fib_main_table;
 #define FIB_TABLE_HASHSZ 1
 static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
 
-static void __init fib4_rules_init(void)
+static int __init fib4_rules_init(void)
 {
         ip_fib_local_table = fib_hash_init(RT_TABLE_LOCAL);
-        hlist_add_head_rcu(&ip_fib_local_table->tb_hlist, &fib_table_hash[0]);
+        if (ip_fib_local_table == NULL)
+                return -ENOMEM;
+
         ip_fib_main_table  = fib_hash_init(RT_TABLE_MAIN);
+        if (ip_fib_main_table == NULL)
+                goto fail;
+
+        hlist_add_head_rcu(&ip_fib_local_table->tb_hlist, &fib_table_hash[0]);
         hlist_add_head_rcu(&ip_fib_main_table->tb_hlist, &fib_table_hash[0]);
+        return 0;
+
+fail:
+        kfree(ip_fib_local_table);
+        ip_fib_local_table = NULL;
+        return -ENOMEM;
 }
 #else
 
@@ -944,7 +956,7 @@ void __init ip_fib_init(void)
         for (i = 0; i < FIB_TABLE_HASHSZ; i++)
                 INIT_HLIST_HEAD(&fib_table_hash[i]);
 
-        fib4_rules_init();
+        BUG_ON(fib4_rules_init());
 
         register_netdevice_notifier(&fib_netdev_notifier);
         register_inetaddr_notifier(&fib_inetaddr_notifier);
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index afe669dd1bd5..0751734ecf41 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -311,8 +311,18 @@ static int __init fib_default_rules_init(void)
         return 0;
 }
 
-void __init fib4_rules_init(void)
+int __init fib4_rules_init()
 {
-        BUG_ON(fib_default_rules_init());
+        int err;
+
         fib_rules_register(&init_net, &fib4_rules_ops);
+        err = fib_default_rules_init();
+        if (err < 0)
+                goto fail;
+        return 0;
+
+fail:
+        /* also cleans all rules already added */
+        fib_rules_unregister(&init_net, &fib4_rules_ops);
+        return err;
 }