[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>

2 files changed, 8 insertions, 5 deletions

diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 6b8a103..b482441 100644
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -150,14 +150,17 @@ static struct proto llc_proto = {
  *	socket type we have available.
  *	Returns 0 upon success, negative upon failure.
  */
-static int llc_ui_create(struct socket *sock, int protocol)
+static int llc_ui_create(struct net *net, struct socket *sock, int protocol)
 {
 	struct sock *sk;
 	int rc = -ESOCKTNOSUPPORT;
 
+	if (net != &init_net)
+		return -EAFNOSUPPORT;
+
 	if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
 		rc = -ENOMEM;
-		sk = llc_sk_alloc(PF_LLC, GFP_KERNEL, &llc_proto);
+		sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto);
 		if (sk) {
 			rc = 0;
 			llc_ui_sk_init(sock, sk);
diff --git a/net/llc/llc_conn.c b/net/llc/llc_conn.c
index 3b8cfbe..8ebc276 100644
--- a/net/llc/llc_conn.c
+++ b/net/llc/llc_conn.c
@@ -700,7 +700,7 @@ static struct sock *llc_create_incoming_sock(struct sock *sk,
 					     struct llc_addr *saddr,
 					     struct llc_addr *daddr)
 {
-	struct sock *newsk = llc_sk_alloc(sk->sk_family, GFP_ATOMIC,
+	struct sock *newsk = llc_sk_alloc(sk->sk_net, sk->sk_family, GFP_ATOMIC,
 					  sk->sk_prot);
 	struct llc_sock *newllc, *llc = llc_sk(sk);
 
@@ -867,9 +867,9 @@ static void llc_sk_init(struct sock* sk)
  *	Allocates a LLC sock and initializes it. Returns the new LLC sock
  *	or %NULL if there's no memory available for one
  */
-struct sock *llc_sk_alloc(int family, gfp_t priority, struct proto *prot)
+struct sock *llc_sk_alloc(struct net *net, int family, gfp_t priority, struct proto *prot)
 {
-	struct sock *sk = sk_alloc(family, priority, prot, 1);
+	struct sock *sk = sk_alloc(net, family, priority, prot, 1);
 
 	if (!sk)
 		goto out;