[NET]: Make socket creation namespace safe.

This patch passes in the namespace a new socket should be created in
and has the socket code do the appropriate reference counting.  By
virtue of this all socket create methods are touched.  In addition
the socket create methods are modified so that they will fail if
you attempt to create a socket in a non-default network namespace.

Failing if we attempt to create a socket outside of the default
network namespace ensures that as we incrementally make the network stack
network namespace aware we will not export functionality that someone
has not audited and made certain is network namespace safe.
Allowing us to partially enable network namespaces before all of the
exotic protocols are supported.

Any protocol layers I have missed will fail to compile because I now
pass an extra parameter into the socket creation code.

[ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 9ef8b5fb7936..74e1f7d90d73 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -56,6 +56,7 @@
 #include <asm/atomic.h>
 #include <net/dst.h>
 #include <net/checksum.h>
+#include <net/net_namespace.h>
 
 /*
  * This structure really needs to be cleaned up.
@@ -776,7 +777,7 @@ extern void FASTCALL(release_sock(struct sock *sk));
                                 SINGLE_DEPTH_NESTING)
 #define bh_unlock_sock(__sk)    spin_unlock(&((__sk)->sk_lock.slock))
 
-extern struct sock              *sk_alloc(int family,
+extern struct sock              *sk_alloc(struct net *net, int family,
                                           gfp_t priority,
                                           struct proto *prot, int zero_it);
 extern void                     sk_free(struct sock *sk);
@@ -1005,6 +1006,7 @@ static inline void sock_copy(struct sock *nsk, const struct sock *osk)
 #endif
 
         memcpy(nsk, osk, osk->sk_prot->obj_size);
+        get_net(nsk->sk_net);
 #ifdef CONFIG_SECURITY_NETWORK
         nsk->sk_security = sptr;
         security_sk_clone(osk, nsk);