system_server: add policy for getConnectionOwnerUid API

Bug: 9496886
Bug: 109758967
Test: atest HostsideVpnTests
Change-Id: I1716d9c740b374b861e691b31ab271c681cf6bff
diff --git a/private/system_server.te b/private/system_server.te
index 7c81c45..7b0ddaa 100644
--- a/private/system_server.te
+++ b/private/system_server.te
@@ -78,6 +78,9 @@
 # Create and share netlink_netfilter_sockets for tetheroffload.
 allow system_server self:netlink_netfilter_socket create_socket_perms_no_ioctl;
 
+# Create/use netlink_tcpdiag_socket for looking up connection UIDs for VPN apps.
+allow system_server self:netlink_tcpdiag_socket { create_socket_perms_no_ioctl nlmsg_read };
+
 # Use netlink uevent sockets.
 allow system_server self:netlink_kobject_uevent_socket create_socket_perms_no_ioctl;