v4.19.13 snapshot.
diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
new file mode 100644
index 0000000..e15cd37
--- /dev/null
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sysctl_net_ipv6.c: sysctl interface to net IPV6 subsystem.
+ *
+ * Changes:
+ * YOSHIFUJI Hideaki @USAGI:	added icmp sysctl table.
+ */
+
+#include <linux/mm.h>
+#include <linux/sysctl.h>
+#include <linux/in6.h>
+#include <linux/ipv6.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <net/ndisc.h>
+#include <net/ipv6.h>
+#include <net/addrconf.h>
+#include <net/inet_frag.h>
+#include <net/netevent.h>
+#ifdef CONFIG_NETLABEL
+#include <net/calipso.h>
+#endif
+
+static int zero;
+static int one = 1;
+static int auto_flowlabels_min;
+static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
+
+static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
+					  void __user *buffer, size_t *lenp,
+					  loff_t *ppos)
+{
+	struct net *net;
+	int ret;
+
+	net = container_of(table->data, struct net,
+			   ipv6.sysctl.multipath_hash_policy);
+	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+	if (write && ret == 0)
+		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
+
+	return ret;
+}
+
+static struct ctl_table ipv6_table_template[] = {
+	{
+		.procname	= "bindv6only",
+		.data		= &init_net.ipv6.sysctl.bindv6only,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "anycast_src_echo_reply",
+		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "flowlabel_consistency",
+		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "auto_flowlabels",
+		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &auto_flowlabels_min,
+		.extra2		= &auto_flowlabels_max
+	},
+	{
+		.procname	= "fwmark_reflect",
+		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "idgen_retries",
+		.data		= &init_net.ipv6.sysctl.idgen_retries,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{
+		.procname	= "idgen_delay",
+		.data		= &init_net.ipv6.sysctl.idgen_delay,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{
+		.procname	= "flowlabel_state_ranges",
+		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "ip_nonlocal_bind",
+		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "flowlabel_reflect",
+		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{
+		.procname	= "max_dst_opts_number",
+		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "max_hbh_opts_number",
+		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "max_dst_opts_length",
+		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "max_hbh_length",
+		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "fib_multipath_hash_policy",
+		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler   = proc_rt6_multipath_hash_policy,
+		.extra1		= &zero,
+		.extra2		= &one,
+	},
+	{
+		.procname	= "seg6_flowlabel",
+		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{ }
+};
+
+static struct ctl_table ipv6_rotable[] = {
+	{
+		.procname	= "mld_max_msf",
+		.data		= &sysctl_mld_max_msf,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "mld_qrv",
+		.data		= &sysctl_mld_qrv,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &one
+	},
+#ifdef CONFIG_NETLABEL
+	{
+		.procname	= "calipso_cache_enable",
+		.data		= &calipso_cache_enabled,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{
+		.procname	= "calipso_cache_bucket_size",
+		.data		= &calipso_cache_bucketsize,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+#endif /* CONFIG_NETLABEL */
+	{ }
+};
+
+static int __net_init ipv6_sysctl_net_init(struct net *net)
+{
+	struct ctl_table *ipv6_table;
+	struct ctl_table *ipv6_route_table;
+	struct ctl_table *ipv6_icmp_table;
+	int err;
+
+	err = -ENOMEM;
+	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
+			     GFP_KERNEL);
+	if (!ipv6_table)
+		goto out;
+	ipv6_table[0].data = &net->ipv6.sysctl.bindv6only;
+	ipv6_table[1].data = &net->ipv6.sysctl.anycast_src_echo_reply;
+	ipv6_table[2].data = &net->ipv6.sysctl.flowlabel_consistency;
+	ipv6_table[3].data = &net->ipv6.sysctl.auto_flowlabels;
+	ipv6_table[4].data = &net->ipv6.sysctl.fwmark_reflect;
+	ipv6_table[5].data = &net->ipv6.sysctl.idgen_retries;
+	ipv6_table[6].data = &net->ipv6.sysctl.idgen_delay;
+	ipv6_table[7].data = &net->ipv6.sysctl.flowlabel_state_ranges;
+	ipv6_table[8].data = &net->ipv6.sysctl.ip_nonlocal_bind;
+	ipv6_table[9].data = &net->ipv6.sysctl.flowlabel_reflect;
+	ipv6_table[10].data = &net->ipv6.sysctl.max_dst_opts_cnt;
+	ipv6_table[11].data = &net->ipv6.sysctl.max_hbh_opts_cnt;
+	ipv6_table[12].data = &net->ipv6.sysctl.max_dst_opts_len;
+	ipv6_table[13].data = &net->ipv6.sysctl.max_hbh_opts_len;
+	ipv6_table[14].data = &net->ipv6.sysctl.multipath_hash_policy,
+	ipv6_table[15].data = &net->ipv6.sysctl.seg6_flowlabel;
+
+	ipv6_route_table = ipv6_route_sysctl_init(net);
+	if (!ipv6_route_table)
+		goto out_ipv6_table;
+
+	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
+	if (!ipv6_icmp_table)
+		goto out_ipv6_route_table;
+
+	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
+	if (!net->ipv6.sysctl.hdr)
+		goto out_ipv6_icmp_table;
+
+	net->ipv6.sysctl.route_hdr =
+		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
+	if (!net->ipv6.sysctl.route_hdr)
+		goto out_unregister_ipv6_table;
+
+	net->ipv6.sysctl.icmp_hdr =
+		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
+	if (!net->ipv6.sysctl.icmp_hdr)
+		goto out_unregister_route_table;
+
+	err = 0;
+out:
+	return err;
+out_unregister_route_table:
+	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
+out_unregister_ipv6_table:
+	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
+out_ipv6_icmp_table:
+	kfree(ipv6_icmp_table);
+out_ipv6_route_table:
+	kfree(ipv6_route_table);
+out_ipv6_table:
+	kfree(ipv6_table);
+	goto out;
+}
+
+static void __net_exit ipv6_sysctl_net_exit(struct net *net)
+{
+	struct ctl_table *ipv6_table;
+	struct ctl_table *ipv6_route_table;
+	struct ctl_table *ipv6_icmp_table;
+
+	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
+	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
+	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
+
+	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
+	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
+	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
+
+	kfree(ipv6_table);
+	kfree(ipv6_route_table);
+	kfree(ipv6_icmp_table);
+}
+
+static struct pernet_operations ipv6_sysctl_net_ops = {
+	.init = ipv6_sysctl_net_init,
+	.exit = ipv6_sysctl_net_exit,
+};
+
+static struct ctl_table_header *ip6_header;
+
+int ipv6_sysctl_register(void)
+{
+	int err = -ENOMEM;
+
+	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
+	if (!ip6_header)
+		goto out;
+
+	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
+	if (err)
+		goto err_pernet;
+out:
+	return err;
+
+err_pernet:
+	unregister_net_sysctl_table(ip6_header);
+	goto out;
+}
+
+void ipv6_sysctl_unregister(void)
+{
+	unregister_net_sysctl_table(ip6_header);
+	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
+}