[IPV4/IPV6]: Fix inet{,6} device initialization order.

It is important that we only assign dev->ip{,6}_ptr
only after all portions of the inet{,6} are setup.

Otherwise we can receive packets before the multicast
spinlocks et al. are initialized.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 5 insertions, 4 deletions

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 84bed40273ad..25c8a42965df 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -165,9 +165,8 @@ struct in_device *inetdev_init(struct net_device *dev)
                               NET_IPV4_NEIGH, "ipv4", NULL, NULL);
 #endif
 
-        /* Account for reference dev->ip_ptr */
+        /* Account for reference dev->ip_ptr (below) */
         in_dev_hold(in_dev);
-        rcu_assign_pointer(dev->ip_ptr, in_dev);
 
 #ifdef CONFIG_SYSCTL
         devinet_sysctl_register(in_dev, &in_dev->cnf);
@@ -176,6 +175,8 @@ struct in_device *inetdev_init(struct net_device *dev)
         if (dev->flags & IFF_UP)
                 ip_mc_up(in_dev);
 out:
+        /* we can receive as soon as ip_ptr is set -- do this last */
+        rcu_assign_pointer(dev->ip_ptr, in_dev);
         return in_dev;
 out_kfree:
         kfree(in_dev);
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 9b0a90643151..171e5b55d7d6 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -413,8 +413,6 @@ static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
         if (netif_carrier_ok(dev))
                 ndev->if_flags |= IF_READY;
 
-        /* protected by rtnl_lock */
-        rcu_assign_pointer(dev->ip6_ptr, ndev);
 
         ipv6_mc_init_dev(ndev);
         ndev->tstamp = jiffies;
@@ -425,6 +423,8 @@ static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
                               NULL);
         addrconf_sysctl_register(ndev, &ndev->cnf);
 #endif
+        /* protected by rtnl_lock */
+        rcu_assign_pointer(dev->ip6_ptr, ndev);
         return ndev;
 }