net ip6 flowlabel: Make owner a union of struct pid * and kuid_t

Correct a long standing omission and use struct pid in the owner
field of struct ip6_flowlabel when the share type is IPV6_FL_S_PROCESS.
This guarantees we don't have issues when pid wraparound occurs.

Use a kuid_t in the owner field of struct ip6_flowlabel when the
share type is IPV6_FL_S_USER to add user namespace support.

In /proc/net/ip6_flowlabel capture the current pid namespace when
opening the file and release the pid namespace when the file is
closed ensuring we print the pid owner value that is meaning to
the reader of the file.  Similarly use from_kuid_munged to print
uid values that are meaningful to the reader of the file.

This requires exporting pid_nr_ns so that ipv6 can continue to built
as a module.  Yoiks what silliness

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>

1 files changed, 0 insertions, 1 deletions

diff --git a/init/Kconfig b/init/Kconfig
index f857f97bcef3..64ff9ce59443 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -948,7 +948,6 @@ config UIDGID_CONVERTED
         depends on NETFILTER_XT_MATCH_RECENT = n
         depends on NETFILTER_XT_TARGET_LOG = n
         depends on NETFILTER_NETLINK_LOG = n
-        depends on IPV6 = n
         depends on AF_RXRPC = n
         depends on NET_KEY = n
         depends on INET_DIAG = n