ipv6: tcp: get rid of tcp_v6_clear_sk()

Now RCU lookups of IPv6 TCP sockets no longer dereference pinet6,
we do not need tcp_v6_clear_sk() anymore.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/tcp_ipv6.c

@@ -1862,17 +1862,6 @@ void tcp6_proc_exit(struct net *net)
 }
 #endif
 
-static void tcp_v6_clear_sk(struct sock *sk, int size)
-{
-	struct inet_sock *inet = inet_sk(sk);
-
-	/* we do not want to clear pinet6 field, because of RCU lookups */
-	sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6));
-
-	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
-	memset(&inet->pinet6 + 1, 0, size);
-}
-
 struct proto tcpv6_prot = {
 	.name			= "TCPv6",
 	.owner			= THIS_MODULE,
@@ -1914,7 +1903,6 @@ struct proto tcpv6_prot = {
 	.compat_setsockopt	= compat_tcp_setsockopt,
 	.compat_getsockopt	= compat_tcp_getsockopt,
 #endif
-	.clear_sk		= tcp_v6_clear_sk,
 	.diag_destroy		= tcp_abort,
 };