Smack security handler for sendmsg() syscall
is vulnerable to type confusion issue what
can allow to privilege escalation into root
or cause denial of service.

A malicious attacker can create socket of one
type for example AF_UNIX and pass is into
sendmsg() function ensuring that this is
AF_INET socket.

Remedy
Do not trust user supplied data.
Proposed fix below.
Signed-off-by: NRoman Kubiak <r.kubiak@samsung.com>
Signed-off-by: NMateusz Fruba <m.fruba@samsung.com>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>