userns: Print out socket uids in a user namespace aware fashion.

Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index e19124b..91e7467 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1509,7 +1509,8 @@
 	sa_family_t		family;
 	enum tcp_seq_states	state;
 	struct sock		*syn_wait_sk;
-	int			bucket, offset, sbucket, num, uid;
+	int			bucket, offset, sbucket, num;
+	kuid_t			uid;
 	loff_t			last_pos;
 };