1 files changed, 33 insertions, 19 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 6b178e1..ff9fb6b 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1344,6 +1344,22 @@ static void netlink_data_ready(struct sock *sk, int len)
  *	queueing.
  */
 
+static void __netlink_release(struct sock *sk)
+{
+	/*
+	 * Last sock_put should drop referrence to sk->sk_net. It has already
+	 * been dropped in netlink_kernel_create. Taking referrence to stopping
+	 * namespace is not an option.
+	 * Take referrence to a socket to remove it from netlink lookup table
+	 * _alive_ and after that destroy it in the context of init_net.
+	 */
+
+	sock_hold(sk);
+	sock_release(sk->sk_socket);
+	sk->sk_net = get_net(&init_net);
+	sock_put(sk);
+}
+
 struct sock *
 netlink_kernel_create(struct net *net, int unit, unsigned int groups,
 		      void (*input)(struct sk_buff *skb),
@@ -1362,8 +1378,18 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
 	if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
 		return NULL;
 
-	if (__netlink_create(net, sock, cb_mutex, unit) < 0)
-		goto out_sock_release;
+	/*
+	 * We have to just have a reference on the net from sk, but don't
+	 * get_net it. Besides, we cannot get and then put the net here.
+	 * So we create one inside init_net and the move it to net.
+	 */
+
+	if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0)
+		goto out_sock_release_nosk;
+
+	sk = sock->sk;
+	put_net(sk->sk_net);
+	sk->sk_net = net;
 
 	if (groups < 32)
 		groups = 32;
@@ -1372,7 +1398,6 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
 	if (!listeners)
 		goto out_sock_release;
 
-	sk = sock->sk;
 	sk->sk_data_ready = netlink_data_ready;
 	if (input)
 		nlk_sk(sk)->netlink_rcv = input;
@@ -1395,14 +1420,14 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
 		nl_table[unit].registered++;
 	}
 	netlink_table_ungrab();
-
-	/* Do not hold an extra referrence to a namespace as this socket is
-	 * internal to a namespace and does not prevent it to stop. */
-	put_net(net);
 	return sk;
 
 out_sock_release:
 	kfree(listeners);
+	__netlink_release(sk);
+	return NULL;
+
+out_sock_release_nosk:
 	sock_release(sock);
 	return NULL;
 }
@@ -1415,18 +1440,7 @@ netlink_kernel_release(struct sock *sk)
 	if (sk == NULL || sk->sk_socket == NULL)
 		return;
 
-	/*
-	 * Last sock_put should drop referrence to sk->sk_net. It has already
-	 * been dropped in netlink_kernel_create. Taking referrence to stopping
-	 * namespace is not an option.
-	 * Take referrence to a socket to remove it from netlink lookup table
-	 * _alive_ and after that destroy it in the context of init_net.
-	 */
-	sock_hold(sk);
-	sock_release(sk->sk_socket);
-
-	sk->sk_net = get_net(&init_net);
-	sock_put(sk);
+	__netlink_release(sk);
 }
 EXPORT_SYMBOL(netlink_kernel_release);