v4.19.13 snapshot.
diff --git a/security/selinux/netlink.c b/security/selinux/netlink.c
new file mode 100644
index 0000000..8a8a725
--- /dev/null
+++ b/security/selinux/netlink.c
@@ -0,0 +1,124 @@
+/*
+ * Netlink event notifications for SELinux.
+ *
+ * Author: James Morris <jmorris@redhat.com>
+ *
+ * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2,
+ * as published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/skbuff.h>
+#include <linux/selinux_netlink.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+
+#include "security.h"
+
+static struct sock *selnl;
+
+static int selnl_msglen(int msgtype)
+{
+ int ret = 0;
+
+ switch (msgtype) {
+ case SELNL_MSG_SETENFORCE:
+ ret = sizeof(struct selnl_msg_setenforce);
+ break;
+
+ case SELNL_MSG_POLICYLOAD:
+ ret = sizeof(struct selnl_msg_policyload);
+ break;
+
+ default:
+ BUG();
+ }
+ return ret;
+}
+
+static void selnl_add_payload(struct nlmsghdr *nlh, int len, int msgtype, void *data)
+{
+ switch (msgtype) {
+ case SELNL_MSG_SETENFORCE: {
+ struct selnl_msg_setenforce *msg = nlmsg_data(nlh);
+
+ memset(msg, 0, len);
+ msg->val = *((int *)data);
+ break;
+ }
+
+ case SELNL_MSG_POLICYLOAD: {
+ struct selnl_msg_policyload *msg = nlmsg_data(nlh);
+
+ memset(msg, 0, len);
+ msg->seqno = *((u32 *)data);
+ break;
+ }
+
+ default:
+ BUG();
+ }
+}
+
+static void selnl_notify(int msgtype, void *data)
+{
+ int len;
+ sk_buff_data_t tmp;
+ struct sk_buff *skb;
+ struct nlmsghdr *nlh;
+
+ len = selnl_msglen(msgtype);
+
+ skb = nlmsg_new(len, GFP_USER);
+ if (!skb)
+ goto oom;
+
+ tmp = skb->tail;
+ nlh = nlmsg_put(skb, 0, 0, msgtype, len, 0);
+ if (!nlh)
+ goto out_kfree_skb;
+ selnl_add_payload(nlh, len, msgtype, data);
+ nlh->nlmsg_len = skb->tail - tmp;
+ NETLINK_CB(skb).dst_group = SELNLGRP_AVC;
+ netlink_broadcast(selnl, skb, 0, SELNLGRP_AVC, GFP_USER);
+out:
+ return;
+
+out_kfree_skb:
+ kfree_skb(skb);
+oom:
+ pr_err("SELinux: OOM in %s\n", __func__);
+ goto out;
+}
+
+void selnl_notify_setenforce(int val)
+{
+ selnl_notify(SELNL_MSG_SETENFORCE, &val);
+}
+
+void selnl_notify_policyload(u32 seqno)
+{
+ selnl_notify(SELNL_MSG_POLICYLOAD, &seqno);
+}
+
+static int __init selnl_init(void)
+{
+ struct netlink_kernel_cfg cfg = {
+ .groups = SELNLGRP_MAX,
+ .flags = NL_CFG_F_NONROOT_RECV,
+ };
+
+ selnl = netlink_kernel_create(&init_net, NETLINK_SELINUX, &cfg);
+ if (selnl == NULL)
+ panic("SELinux: Cannot create netlink socket.");
+ return 0;
+}
+
+__initcall(selnl_init);