netlabel: add address family checks to netlbl_{sock,req}_delattr()

BugLink: http://bugs.launchpad.net/bugs/1615620

commit 0e0e3677 upstream.

It seems risky to always rely on the caller to ensure the socket's
address family is correct before passing it to the NetLabel kAPI,
especially since we see at least one LSM which didn't. Add address
family checks to the *_delattr() functions to help prevent future
problems.
Reported-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

net/netlabel/netlabel_kapi.c

@@ -824,7 +824,11 @@ int netlbl_sock_setattr(struct sock *sk,
  */
 void netlbl_sock_delattr(struct sock *sk)
 {
-	cipso_v4_sock_delattr(sk);
+	switch (sk->sk_family) {
+	case AF_INET:
+		cipso_v4_sock_delattr(sk);
+		break;
+	}
 }
 
 /**
@@ -987,7 +991,11 @@ int netlbl_req_setattr(struct request_sock *req,
 */
 void netlbl_req_delattr(struct request_sock *req)
 {
-	cipso_v4_req_delattr(req);
+	switch (req->rsk_ops->family) {
+	case AF_INET:
+		cipso_v4_req_delattr(req);
+		break;
+	}
 }
 
 /**