Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1436 commits)
  cassini: Use local-mac-address prom property for Cassini MAC address
  net: remove the duplicate #ifdef __KERNEL__
  net: bridge: check the length of skb after nf_bridge_maybe_copy_header()
  netconsole: clarify stopping message
  netconsole: don't announce stopping if nothing happened
  cnic: Fix the type field in SPQ messages
  netfilter: fix export secctx error handling
  netfilter: fix the race when initializing nf_ct_expect_hash_rnd
  ipv4: IP defragmentation must be ECN aware
  net: r6040: Return proper error for r6040_init_one
  dcb: use after free in dcb_flushapp()
  dcb: unlock on error in dcbnl_ieee_get()
  net: ixp4xx_eth: Return proper error for eth_init_one
  include/linux/if_ether.h: Add #define ETH_P_LINK_CTL for HPNA and wlan local tunnel
  net: add POLLPRI to sock_def_readable()
  af_unix: Avoid socket->sk NULL OOPS in stream connect security hooks.
  net_sched: pfifo_head_drop problem
  mac80211: remove stray extern
  mac80211: implement off-channel TX using hw r-o-c offload
  mac80211: implement hardware offload for remain-on-channel
  ...

1 files changed, 6 insertions, 5 deletions

diff --git a/net/socket.c b/net/socket.c
index 088fb3fd45e0..c1663c0ff3d3 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -156,7 +156,7 @@ static const struct file_operations socket_file_ops = {
  */
 
 static DEFINE_SPINLOCK(net_family_lock);
-static const struct net_proto_family *net_families[NPROTO] __read_mostly;
+static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
 
 /*
  *      Statistics counters of the socket lists
@@ -1215,7 +1215,7 @@ int __sock_create(struct net *net, int family, int type, int protocol,
          * requested real, full-featured networking support upon configuration.
          * Otherwise module support will break!
          */
-        if (net_families[family] == NULL)
+        if (rcu_access_pointer(net_families[family]) == NULL)
                 request_module("net-pf-%d", family);
 #endif
 
@@ -2347,10 +2347,11 @@ int sock_register(const struct net_proto_family *ops)
         }
 
         spin_lock(&net_family_lock);
-        if (net_families[ops->family])
+        if (rcu_dereference_protected(net_families[ops->family],
+                                      lockdep_is_held(&net_family_lock)))
                 err = -EEXIST;
         else {
-                net_families[ops->family] = ops;
+                rcu_assign_pointer(net_families[ops->family], ops);
                 err = 0;
         }
         spin_unlock(&net_family_lock);
@@ -2378,7 +2379,7 @@ void sock_unregister(int family)
         BUG_ON(family < 0 || family >= NPROTO);
 
         spin_lock(&net_family_lock);
-        net_families[family] = NULL;
+        rcu_assign_pointer(net_families[family], NULL);
         spin_unlock(&net_family_lock);
 
         synchronize_rcu();