Merge branch 'inet_diag-TCP-MD5'

Ivan Delalande says:

====================
inet_diag: report TCP MD5 signing keys and addresses

Allow userspace to retrieve MD5 signature keys and addresses configured
on TCP sockets through inet_diag.

Thanks to Eric Dumazet and Stephen Hemminger for their useful
explanations and feedback.

v5: - memset the whole netlink payload after it has been nla_reserve-d
      in tcp_diag_put_md5sig (a third memset had to be added for
      tcpm_key so we might as well have just one for entire region).
    - move the nla_total_size call from inet_sk_attr_size to the
      idiag_get_aux_size defined by protocols as they could add multiple
      netlink attributes,
    - add check for net_admin in tcp_diag_get_aux_size.

v4: - add new struct tcp_diag_md5sig to report the data instead of
      tcp_md5sig to avoid wasting 112 bytes on every tcpm_addr,
    - memset tcpm_addr on IPv4 addresses to avoid leaks,
    - style fix in inet_diag_dump_one_icsk.

v3: - rename inet_diag_*md5sig in tcp_diag.c to tcp_diag_* for
      consistency,
    - don't lock the socket in tcp_diag_put_md5sig,
    - add checks on md5sig_count in tcp_diag_put_md5sig to not create
      the netlink attribute if the list is empty, and to avoid overflows
      or memory leaks if the list has changed in the meantime.

v2: - move changes to tcp_diag.c and extend inet_diag_handler to allow
      protocols to provide additional data on INET_DIAG_INFO,
    - lock socket before calling tcp_diag_put_md5sig.

I also have a patch for iproute2/ss to test this change, making it print
this new attribute. I'm planning to polish and send it if this series
gets applied.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>