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>

net/ipv4/raw.c

@@ -992,7 +992,9 @@ static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i)
 		i, src, srcp, dest, destp, sp->sk_state,
 		sk_wmem_alloc_get(sp),
 		sk_rmem_alloc_get(sp),
-		0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
+		0, 0L, 0,
+		from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
+		0, sock_i_ino(sp),
 		atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops));
 }