Define smc_socket security class.

Linux kernel commit da69a5306ab9 ("selinux: support distinctions among all
network address families") triggers a build error if a new address family
is added without defining a corresponding SELinux security class.  As a
result, the smc_socket class was added to the kernel to resolve a build
failure as part of merge commit 3051bf36c25d that introduced AF_SMC circa
Linux 4.11.  Define this security class and its access vector, add
it to the socket_class_set macro, and exclude it from webview_zygote
like other socket classes.

Test:  Policy builds

Change-Id: Idbb8139bb09c6d1c47f1a76bd10f4ce1e9d939cb
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>

private/access_vectors

@@ -657,6 +657,9 @@ inherits socket
 class qipcrtr_socket
 inherits socket
 
+class smc_socket
+inherits socket
+
 class property_service
 {
 	set

private/security_classes

@@ -127,6 +127,7 @@ class nfc_socket
 class vsock_socket
 class kcm_socket
 class qipcrtr_socket
+class smc_socket
 
 # Property service
 class property_service          # userspace

private/webview_zygote.te

@@ -109,7 +109,7 @@ neverallow webview_zygote domain:{
   x25_socket rose_socket decnet_socket atmsvc_socket rds_socket irda_socket
   pppox_socket llc_socket can_socket tipc_socket bluetooth_socket iucv_socket
   rxrpc_socket isdn_socket phonet_socket ieee802154_socket caif_socket
-  alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket
+  alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket smc_socket
 } *;
 
 # Do not allow access to Bluetooth-related system properties.

public/global_macros

@@ -8,7 +8,7 @@ define(`notdevfile_class_set', `{ file lnk_file sock_file fifo_file }')
 define(`file_class_set', `{ devfile_class_set notdevfile_class_set }')
 define(`dir_file_class_set', `{ dir file_class_set }')
 
-define(`socket_class_set', `{ socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket appletalk_socket netlink_route_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket netlink_generic_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket sctp_socket icmp_socket ax25_socket ipx_socket netrom_socket atmpvc_socket x25_socket rose_socket decnet_socket atmsvc_socket rds_socket irda_socket pppox_socket llc_socket can_socket tipc_socket bluetooth_socket iucv_socket rxrpc_socket isdn_socket phonet_socket ieee802154_socket caif_socket alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket }')
+define(`socket_class_set', `{ socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket appletalk_socket netlink_route_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket netlink_generic_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket sctp_socket icmp_socket ax25_socket ipx_socket netrom_socket atmpvc_socket x25_socket rose_socket decnet_socket atmsvc_socket rds_socket irda_socket pppox_socket llc_socket can_socket tipc_socket bluetooth_socket iucv_socket rxrpc_socket isdn_socket phonet_socket ieee802154_socket caif_socket alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket smc_socket }')
 define(`dgram_socket_class_set', `{ udp_socket unix_dgram_socket }')
 define(`stream_socket_class_set', `{ tcp_socket unix_stream_socket }')
 define(`unpriv_socket_class_set', `{ tcp_socket udp_socket unix_stream_socket unix_dgram_socket }')