[NET]: Make netlink_kernel_release publically available as sk_release_kernel.

This staff will be needed for non-netlink kernel sockets, which should
also not pin a namespace like tcp_socket and icmp_socket.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 0 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index 09cb3a74de7f..c71b645a78f0 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -987,6 +987,24 @@ void sk_free(struct sock *sk)
 	sk_prot_free(sk->sk_prot_creator, sk);
 }
 
+/*
+ * Last sock_put should drop referrence to sk->sk_net. It has already
+ * been dropped in sk_change_net. Taking referrence to stopping namespace
+ * is not an option.
+ * Take referrence to a socket to remove it from hash _alive_ and after that
+ * destroy it in the context of init_net.
+ */
+void sk_release_kernel(struct sock *sk)
+{
+	if (sk == NULL || sk->sk_socket == NULL)
+		return;
+
+	sock_hold(sk);
+	sock_release(sk->sk_socket);
+	sk->sk_net = get_net(&init_net);
+	sock_put(sk);
+}
+
 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
 {
 	struct sock *newsk;