Merge branch 'kernel_socket_netns'

Eric W. Biederman says:

====================
Cleanup the kernel sockets.

Right now the situtation for allocating kernel sockets is a mess.
- sock_create_kern does not take a namespace parameter.
- kernel sockets must not reference count a network namespace and keep
  it alive or else we will have a reference counting loop.
- The way we avoid the reference counting loop with sk_change_net
  and sk_release_kernel are major hacks.

This patchset addresses this mess by fixing sock_create_kern to do
everything necessary to create a kernel socket.  None of the current
users of kernel sockets need the network namespace reference counted.
Either kernel sockets are network namespace aware (and using the current
hacks) or kernel sockets are limited to the initial network namespace
in which case it does not matter.

This patchset starts by addressing tun which should be using normal
userspace sockets like macvtap.

Then sock_create_kern is fixed to take a network namespace.
Then the in kernel status of sockets are passed through to sk_alloc.
Then sk_alloc is fixed to not reference count the network namespace
     of kernel sockets.
Then the callers of sock_create_kern are fixed up to stop using hacks.
Then netlink which uses it's own flavor of sock_create_kern is fixed.

Finally the hacks that are sk_change_net and sk_release_kernel are removed.

When it is all done the code is easier to follow, easier to use, easier
to maintain and shorter by about 70 lines.
====================

Reported-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 5 deletions

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index a7278f05eafb..244287706f91 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -43,7 +43,7 @@ static struct bt_sock_list l2cap_sk_list = {
 static const struct proto_ops l2cap_sock_ops;
 static void l2cap_sock_init(struct sock *sk, struct sock *parent);
 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
-				     int proto, gfp_t prio);
+				     int proto, gfp_t prio, int kern);
 
 bool l2cap_is_socket(struct socket *sock)
 {
@@ -1193,7 +1193,7 @@ static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
 	}
 
 	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
-			      GFP_ATOMIC);
+			      GFP_ATOMIC, 0);
 	if (!sk) {
 		release_sock(parent);
 		return NULL;
@@ -1523,12 +1523,12 @@ static struct proto l2cap_proto = {
 };
 
 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
-				     int proto, gfp_t prio)
+				     int proto, gfp_t prio, int kern)
 {
 	struct sock *sk;
 	struct l2cap_chan *chan;
 
-	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto);
+	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto, kern);
 	if (!sk)
 		return NULL;
 
@@ -1574,7 +1574,7 @@ static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
 
 	sock->ops = &l2cap_sock_ops;
 
-	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC);
+	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
 	if (!sk)
 		return -ENOMEM;