Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2626 insertions, 0 deletions

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
new file mode 100644
index 0000000000..30ca064b76
--- /dev/null
+++ b/net/ipv6/ip6mr.c
@@ -0,0 +1,2626 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	Linux IPv6 multicast routing support for BSD pim6sd
+ *	Based on net/ipv4/ipmr.c.
+ *
+ *	(c) 2004 Mickael Hoerdt, <hoerdt@clarinet.u-strasbg.fr>
+ *		LSIIT Laboratory, Strasbourg, France
+ *	(c) 2004 Jean-Philippe Andriot, <jean-philippe.andriot@6WIND.com>
+ *		6WIND, Paris, France
+ *	Copyright (C)2007,2008 USAGI/WIDE Project
+ *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
+ */
+
+#include <linux/uaccess.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/socket.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/compat.h>
+#include <linux/rhashtable.h>
+#include <net/protocol.h>
+#include <linux/skbuff.h>
+#include <net/raw.h>
+#include <linux/notifier.h>
+#include <linux/if_arp.h>
+#include <net/checksum.h>
+#include <net/netlink.h>
+#include <net/fib_rules.h>
+
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <linux/mroute6.h>
+#include <linux/pim.h>
+#include <net/addrconf.h>
+#include <linux/netfilter_ipv6.h>
+#include <linux/export.h>
+#include <net/ip6_checksum.h>
+#include <linux/netconf.h>
+#include <net/ip_tunnels.h>
+
+#include <linux/nospec.h>
+
+struct ip6mr_rule {
+	struct fib_rule		common;
+};
+
+struct ip6mr_result {
+	struct mr_table	*mrt;
+};
+
+/* Big lock, protecting vif table, mrt cache and mroute socket state.
+   Note that the changes are semaphored via rtnl_lock.
+ */
+
+static DEFINE_SPINLOCK(mrt_lock);
+
+static struct net_device *vif_dev_read(const struct vif_device *vif)
+{
+	return rcu_dereference(vif->dev);
+}
+
+/* Multicast router control variables */
+
+/* Special spinlock for queue of unresolved entries */
+static DEFINE_SPINLOCK(mfc_unres_lock);
+
+/* We return to original Alan's scheme. Hash table of resolved
+   entries is changed only in process context and protected
+   with weak lock mrt_lock. Queue of unresolved entries is protected
+   with strong spinlock mfc_unres_lock.
+
+   In this case data path is free of exclusive locks at all.
+ */
+
+static struct kmem_cache *mrt_cachep __read_mostly;
+
+static struct mr_table *ip6mr_new_table(struct net *net, u32 id);
+static void ip6mr_free_table(struct mr_table *mrt);
+
+static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
+			   struct net_device *dev, struct sk_buff *skb,
+			   struct mfc6_cache *cache);
+static int ip6mr_cache_report(const struct mr_table *mrt, struct sk_buff *pkt,
+			      mifi_t mifi, int assert);
+static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
+			      int cmd);
+static void mrt6msg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt);
+static int ip6mr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
+			      struct netlink_ext_ack *extack);
+static int ip6mr_rtm_dumproute(struct sk_buff *skb,
+			       struct netlink_callback *cb);
+static void mroute_clean_tables(struct mr_table *mrt, int flags);
+static void ipmr_expire_process(struct timer_list *t);
+
+#ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
+#define ip6mr_for_each_table(mrt, net) \
+	list_for_each_entry_rcu(mrt, &net->ipv6.mr6_tables, list, \
+				lockdep_rtnl_is_held() || \
+				list_empty(&net->ipv6.mr6_tables))
+
+static struct mr_table *ip6mr_mr_table_iter(struct net *net,
+					    struct mr_table *mrt)
+{
+	struct mr_table *ret;
+
+	if (!mrt)
+		ret = list_entry_rcu(net->ipv6.mr6_tables.next,
+				     struct mr_table, list);
+	else
+		ret = list_entry_rcu(mrt->list.next,
+				     struct mr_table, list);
+
+	if (&ret->list == &net->ipv6.mr6_tables)
+		return NULL;
+	return ret;
+}
+
+static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
+{
+	struct mr_table *mrt;
+
+	ip6mr_for_each_table(mrt, net) {
+		if (mrt->id == id)
+			return mrt;
+	}
+	return NULL;
+}
+
+static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
+			    struct mr_table **mrt)
+{
+	int err;
+	struct ip6mr_result res;
+	struct fib_lookup_arg arg = {
+		.result = &res,
+		.flags = FIB_LOOKUP_NOREF,
+	};
+
+	/* update flow if oif or iif point to device enslaved to l3mdev */
+	l3mdev_update_flow(net, flowi6_to_flowi(flp6));
+
+	err = fib_rules_lookup(net->ipv6.mr6_rules_ops,
+			       flowi6_to_flowi(flp6), 0, &arg);
+	if (err < 0)
+		return err;
+	*mrt = res.mrt;
+	return 0;
+}
+
+static int ip6mr_rule_action(struct fib_rule *rule, struct flowi *flp,
+			     int flags, struct fib_lookup_arg *arg)
+{
+	struct ip6mr_result *res = arg->result;
+	struct mr_table *mrt;
+
+	switch (rule->action) {
+	case FR_ACT_TO_TBL:
+		break;
+	case FR_ACT_UNREACHABLE:
+		return -ENETUNREACH;
+	case FR_ACT_PROHIBIT:
+		return -EACCES;
+	case FR_ACT_BLACKHOLE:
+	default:
+		return -EINVAL;
+	}
+
+	arg->table = fib_rule_get_table(rule, arg);
+
+	mrt = ip6mr_get_table(rule->fr_net, arg->table);
+	if (!mrt)
+		return -EAGAIN;
+	res->mrt = mrt;
+	return 0;
+}
+
+static int ip6mr_rule_match(struct fib_rule *rule, struct flowi *flp, int flags)
+{
+	return 1;
+}
+
+static int ip6mr_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
+				struct fib_rule_hdr *frh, struct nlattr **tb,
+				struct netlink_ext_ack *extack)
+{
+	return 0;
+}
+
+static int ip6mr_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
+			      struct nlattr **tb)
+{
+	return 1;
+}
+
+static int ip6mr_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
+			   struct fib_rule_hdr *frh)
+{
+	frh->dst_len = 0;
+	frh->src_len = 0;
+	frh->tos     = 0;
+	return 0;
+}
+
+static const struct fib_rules_ops __net_initconst ip6mr_rules_ops_template = {
+	.family		= RTNL_FAMILY_IP6MR,
+	.rule_size	= sizeof(struct ip6mr_rule),
+	.addr_size	= sizeof(struct in6_addr),
+	.action		= ip6mr_rule_action,
+	.match		= ip6mr_rule_match,
+	.configure	= ip6mr_rule_configure,
+	.compare	= ip6mr_rule_compare,
+	.fill		= ip6mr_rule_fill,
+	.nlgroup	= RTNLGRP_IPV6_RULE,
+	.owner		= THIS_MODULE,
+};
+
+static int __net_init ip6mr_rules_init(struct net *net)
+{
+	struct fib_rules_ops *ops;
+	struct mr_table *mrt;
+	int err;
+
+	ops = fib_rules_register(&ip6mr_rules_ops_template, net);
+	if (IS_ERR(ops))
+		return PTR_ERR(ops);
+
+	INIT_LIST_HEAD(&net->ipv6.mr6_tables);
+
+	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
+	if (IS_ERR(mrt)) {
+		err = PTR_ERR(mrt);
+		goto err1;
+	}
+
+	err = fib_default_rule_add(ops, 0x7fff, RT6_TABLE_DFLT, 0);
+	if (err < 0)
+		goto err2;
+
+	net->ipv6.mr6_rules_ops = ops;
+	return 0;
+
+err2:
+	rtnl_lock();
+	ip6mr_free_table(mrt);
+	rtnl_unlock();
+err1:
+	fib_rules_unregister(ops);
+	return err;
+}
+
+static void __net_exit ip6mr_rules_exit(struct net *net)
+{
+	struct mr_table *mrt, *next;
+
+	ASSERT_RTNL();
+	list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
+		list_del(&mrt->list);
+		ip6mr_free_table(mrt);
+	}
+	fib_rules_unregister(net->ipv6.mr6_rules_ops);
+}
+
+static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
+			    struct netlink_ext_ack *extack)
+{
+	return fib_rules_dump(net, nb, RTNL_FAMILY_IP6MR, extack);
+}
+
+static unsigned int ip6mr_rules_seq_read(struct net *net)
+{
+	return fib_rules_seq_read(net, RTNL_FAMILY_IP6MR);
+}
+
+bool ip6mr_rule_default(const struct fib_rule *rule)
+{
+	return fib_rule_matchall(rule) && rule->action == FR_ACT_TO_TBL &&
+	       rule->table == RT6_TABLE_DFLT && !rule->l3mdev;
+}
+EXPORT_SYMBOL(ip6mr_rule_default);
+#else
+#define ip6mr_for_each_table(mrt, net) \
+	for (mrt = net->ipv6.mrt6; mrt; mrt = NULL)
+
+static struct mr_table *ip6mr_mr_table_iter(struct net *net,
+					    struct mr_table *mrt)
+{
+	if (!mrt)
+		return net->ipv6.mrt6;
+	return NULL;
+}
+
+static struct mr_table *ip6mr_get_table(struct net *net, u32 id)
+{
+	return net->ipv6.mrt6;
+}
+
+static int ip6mr_fib_lookup(struct net *net, struct flowi6 *flp6,
+			    struct mr_table **mrt)
+{
+	*mrt = net->ipv6.mrt6;
+	return 0;
+}
+
+static int __net_init ip6mr_rules_init(struct net *net)
+{
+	struct mr_table *mrt;
+
+	mrt = ip6mr_new_table(net, RT6_TABLE_DFLT);
+	if (IS_ERR(mrt))
+		return PTR_ERR(mrt);
+	net->ipv6.mrt6 = mrt;
+	return 0;
+}
+
+static void __net_exit ip6mr_rules_exit(struct net *net)
+{
+	ASSERT_RTNL();
+	ip6mr_free_table(net->ipv6.mrt6);
+	net->ipv6.mrt6 = NULL;
+}
+
+static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
+			    struct netlink_ext_ack *extack)
+{
+	return 0;
+}
+
+static unsigned int ip6mr_rules_seq_read(struct net *net)
+{
+	return 0;
+}
+#endif
+
+static int ip6mr_hash_cmp(struct rhashtable_compare_arg *arg,
+			  const void *ptr)
+{
+	const struct mfc6_cache_cmp_arg *cmparg = arg->key;
+	struct mfc6_cache *c = (struct mfc6_cache *)ptr;
+
+	return !ipv6_addr_equal(&c->mf6c_mcastgrp, &cmparg->mf6c_mcastgrp) ||
+	       !ipv6_addr_equal(&c->mf6c_origin, &cmparg->mf6c_origin);
+}
+
+static const struct rhashtable_params ip6mr_rht_params = {
+	.head_offset = offsetof(struct mr_mfc, mnode),
+	.key_offset = offsetof(struct mfc6_cache, cmparg),
+	.key_len = sizeof(struct mfc6_cache_cmp_arg),
+	.nelem_hint = 3,
+	.obj_cmpfn = ip6mr_hash_cmp,
+	.automatic_shrinking = true,
+};
+
+static void ip6mr_new_table_set(struct mr_table *mrt,
+				struct net *net)
+{
+#ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
+	list_add_tail_rcu(&mrt->list, &net->ipv6.mr6_tables);
+#endif
+}
+
+static struct mfc6_cache_cmp_arg ip6mr_mr_table_ops_cmparg_any = {
+	.mf6c_origin = IN6ADDR_ANY_INIT,
+	.mf6c_mcastgrp = IN6ADDR_ANY_INIT,
+};
+
+static struct mr_table_ops ip6mr_mr_table_ops = {
+	.rht_params = &ip6mr_rht_params,
+	.cmparg_any = &ip6mr_mr_table_ops_cmparg_any,
+};
+
+static struct mr_table *ip6mr_new_table(struct net *net, u32 id)
+{
+	struct mr_table *mrt;
+
+	mrt = ip6mr_get_table(net, id);
+	if (mrt)
+		return mrt;
+
+	return mr_table_alloc(net, id, &ip6mr_mr_table_ops,
+			      ipmr_expire_process, ip6mr_new_table_set);
+}
+
+static void ip6mr_free_table(struct mr_table *mrt)
+{
+	timer_shutdown_sync(&mrt->ipmr_expire_timer);
+	mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC |
+				 MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC);
+	rhltable_destroy(&mrt->mfc_hash);
+	kfree(mrt);
+}
+
+#ifdef CONFIG_PROC_FS
+/* The /proc interfaces to multicast routing
+ * /proc/ip6_mr_cache /proc/ip6_mr_vif
+ */
+
+static void *ip6mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(RCU)
+{
+	struct mr_vif_iter *iter = seq->private;
+	struct net *net = seq_file_net(seq);
+	struct mr_table *mrt;
+
+	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
+	if (!mrt)
+		return ERR_PTR(-ENOENT);
+
+	iter->mrt = mrt;
+
+	rcu_read_lock();
+	return mr_vif_seq_start(seq, pos);
+}
+
+static void ip6mr_vif_seq_stop(struct seq_file *seq, void *v)
+	__releases(RCU)
+{
+	rcu_read_unlock();
+}
+
+static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
+{
+	struct mr_vif_iter *iter = seq->private;
+	struct mr_table *mrt = iter->mrt;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq,
+			 "Interface      BytesIn  PktsIn  BytesOut PktsOut Flags\n");
+	} else {
+		const struct vif_device *vif = v;
+		const struct net_device *vif_dev;
+		const char *name;
+
+		vif_dev = vif_dev_read(vif);
+		name = vif_dev ? vif_dev->name : "none";
+
+		seq_printf(seq,
+			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X\n",
+			   vif - mrt->vif_table,
+			   name, vif->bytes_in, vif->pkt_in,
+			   vif->bytes_out, vif->pkt_out,
+			   vif->flags);
+	}
+	return 0;
+}
+
+static const struct seq_operations ip6mr_vif_seq_ops = {
+	.start = ip6mr_vif_seq_start,
+	.next  = mr_vif_seq_next,
+	.stop  = ip6mr_vif_seq_stop,
+	.show  = ip6mr_vif_seq_show,
+};
+
+static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct net *net = seq_file_net(seq);
+	struct mr_table *mrt;
+
+	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
+	if (!mrt)
+		return ERR_PTR(-ENOENT);
+
+	return mr_mfc_seq_start(seq, pos, mrt, &mfc_unres_lock);
+}
+
+static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
+{
+	int n;
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq,
+			 "Group                            "
+			 "Origin                           "
+			 "Iif      Pkts  Bytes     Wrong  Oifs\n");
+	} else {
+		const struct mfc6_cache *mfc = v;
+		const struct mr_mfc_iter *it = seq->private;
+		struct mr_table *mrt = it->mrt;
+
+		seq_printf(seq, "%pI6 %pI6 %-3hd",
+			   &mfc->mf6c_mcastgrp, &mfc->mf6c_origin,
+			   mfc->_c.mfc_parent);
+
+		if (it->cache != &mrt->mfc_unres_queue) {
+			seq_printf(seq, " %8lu %8lu %8lu",
+				   mfc->_c.mfc_un.res.pkt,
+				   mfc->_c.mfc_un.res.bytes,
+				   mfc->_c.mfc_un.res.wrong_if);
+			for (n = mfc->_c.mfc_un.res.minvif;
+			     n < mfc->_c.mfc_un.res.maxvif; n++) {
+				if (VIF_EXISTS(mrt, n) &&
+				    mfc->_c.mfc_un.res.ttls[n] < 255)
+					seq_printf(seq,
+						   " %2d:%-3d", n,
+						   mfc->_c.mfc_un.res.ttls[n]);
+			}
+		} else {
+			/* unresolved mfc_caches don't contain
+			 * pkt, bytes and wrong_if values
+			 */
+			seq_printf(seq, " %8lu %8lu %8lu", 0ul, 0ul, 0ul);
+		}
+		seq_putc(seq, '\n');
+	}
+	return 0;
+}
+
+static const struct seq_operations ipmr_mfc_seq_ops = {
+	.start = ipmr_mfc_seq_start,
+	.next  = mr_mfc_seq_next,
+	.stop  = mr_mfc_seq_stop,
+	.show  = ipmr_mfc_seq_show,
+};
+#endif
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+
+static int pim6_rcv(struct sk_buff *skb)
+{
+	struct pimreghdr *pim;
+	struct ipv6hdr   *encap;
+	struct net_device  *reg_dev = NULL;
+	struct net *net = dev_net(skb->dev);
+	struct mr_table *mrt;
+	struct flowi6 fl6 = {
+		.flowi6_iif	= skb->dev->ifindex,
+		.flowi6_mark	= skb->mark,
+	};
+	int reg_vif_num;
+
+	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
+		goto drop;
+
+	pim = (struct pimreghdr *)skb_transport_header(skb);
+	if (pim->type != ((PIM_VERSION << 4) | PIM_TYPE_REGISTER) ||
+	    (pim->flags & PIM_NULL_REGISTER) ||
+	    (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
+			     sizeof(*pim), IPPROTO_PIM,
+			     csum_partial((void *)pim, sizeof(*pim), 0)) &&
+	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
+		goto drop;
+
+	/* check if the inner packet is destined to mcast group */
+	encap = (struct ipv6hdr *)(skb_transport_header(skb) +
+				   sizeof(*pim));
+
+	if (!ipv6_addr_is_multicast(&encap->daddr) ||
+	    encap->payload_len == 0 ||
+	    ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
+		goto drop;
+
+	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
+		goto drop;
+
+	/* Pairs with WRITE_ONCE() in mif6_add()/mif6_delete() */
+	reg_vif_num = READ_ONCE(mrt->mroute_reg_vif_num);
+	if (reg_vif_num >= 0)
+		reg_dev = vif_dev_read(&mrt->vif_table[reg_vif_num]);
+
+	if (!reg_dev)
+		goto drop;
+
+	skb->mac_header = skb->network_header;
+	skb_pull(skb, (u8 *)encap - skb->data);
+	skb_reset_network_header(skb);
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->ip_summed = CHECKSUM_NONE;
+
+	skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
+
+	netif_rx(skb);
+
+	return 0;
+ drop:
+	kfree_skb(skb);
+	return 0;
+}
+
+static const struct inet6_protocol pim6_protocol = {
+	.handler	=	pim6_rcv,
+};
+
+/* Service routines creating virtual interfaces: PIMREG */
+
+static netdev_tx_t reg_vif_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct net *net = dev_net(dev);
+	struct mr_table *mrt;
+	struct flowi6 fl6 = {
+		.flowi6_oif	= dev->ifindex,
+		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
+		.flowi6_mark	= skb->mark,
+	};
+
+	if (!pskb_inet_may_pull(skb))
+		goto tx_err;
+
+	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
+		goto tx_err;
+
+	DEV_STATS_ADD(dev, tx_bytes, skb->len);
+	DEV_STATS_INC(dev, tx_packets);
+	rcu_read_lock();
+	ip6mr_cache_report(mrt, skb, READ_ONCE(mrt->mroute_reg_vif_num),
+			   MRT6MSG_WHOLEPKT);
+	rcu_read_unlock();
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+
+tx_err:
+	DEV_STATS_INC(dev, tx_errors);
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static int reg_vif_get_iflink(const struct net_device *dev)
+{
+	return 0;
+}
+
+static const struct net_device_ops reg_vif_netdev_ops = {
+	.ndo_start_xmit	= reg_vif_xmit,
+	.ndo_get_iflink = reg_vif_get_iflink,
+};
+
+static void reg_vif_setup(struct net_device *dev)
+{
+	dev->type		= ARPHRD_PIMREG;
+	dev->mtu		= 1500 - sizeof(struct ipv6hdr) - 8;
+	dev->flags		= IFF_NOARP;
+	dev->netdev_ops		= &reg_vif_netdev_ops;
+	dev->needs_free_netdev	= true;
+	dev->features		|= NETIF_F_NETNS_LOCAL;
+}
+
+static struct net_device *ip6mr_reg_vif(struct net *net, struct mr_table *mrt)
+{
+	struct net_device *dev;
+	char name[IFNAMSIZ];
+
+	if (mrt->id == RT6_TABLE_DFLT)
+		sprintf(name, "pim6reg");
+	else
+		sprintf(name, "pim6reg%u", mrt->id);
+
+	dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, reg_vif_setup);
+	if (!dev)
+		return NULL;
+
+	dev_net_set(dev, net);
+
+	if (register_netdevice(dev)) {
+		free_netdev(dev);
+		return NULL;
+	}
+
+	if (dev_open(dev, NULL))
+		goto failure;
+
+	dev_hold(dev);
+	return dev;
+
+failure:
+	unregister_netdevice(dev);
+	return NULL;
+}
+#endif
+
+static int call_ip6mr_vif_entry_notifiers(struct net *net,
+					  enum fib_event_type event_type,
+					  struct vif_device *vif,
+					  struct net_device *vif_dev,
+					  mifi_t vif_index, u32 tb_id)
+{
+	return mr_call_vif_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
+				     vif, vif_dev, vif_index, tb_id,
+				     &net->ipv6.ipmr_seq);
+}
+
+static int call_ip6mr_mfc_entry_notifiers(struct net *net,
+					  enum fib_event_type event_type,
+					  struct mfc6_cache *mfc, u32 tb_id)
+{
+	return mr_call_mfc_notifiers(net, RTNL_FAMILY_IP6MR, event_type,
+				     &mfc->_c, tb_id, &net->ipv6.ipmr_seq);
+}
+
+/* Delete a VIF entry */
+static int mif6_delete(struct mr_table *mrt, int vifi, int notify,
+		       struct list_head *head)
+{
+	struct vif_device *v;
+	struct net_device *dev;
+	struct inet6_dev *in6_dev;
+
+	if (vifi < 0 || vifi >= mrt->maxvif)
+		return -EADDRNOTAVAIL;
+
+	v = &mrt->vif_table[vifi];
+
+	dev = rtnl_dereference(v->dev);
+	if (!dev)
+		return -EADDRNOTAVAIL;
+
+	call_ip6mr_vif_entry_notifiers(read_pnet(&mrt->net),
+				       FIB_EVENT_VIF_DEL, v, dev,
+				       vifi, mrt->id);
+	spin_lock(&mrt_lock);
+	RCU_INIT_POINTER(v->dev, NULL);
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (vifi == mrt->mroute_reg_vif_num) {
+		/* Pairs with READ_ONCE() in ip6mr_cache_report() and reg_vif_xmit() */
+		WRITE_ONCE(mrt->mroute_reg_vif_num, -1);
+	}
+#endif
+
+	if (vifi + 1 == mrt->maxvif) {
+		int tmp;
+		for (tmp = vifi - 1; tmp >= 0; tmp--) {
+			if (VIF_EXISTS(mrt, tmp))
+				break;
+		}
+		WRITE_ONCE(mrt->maxvif, tmp + 1);
+	}
+
+	spin_unlock(&mrt_lock);
+
+	dev_set_allmulti(dev, -1);
+
+	in6_dev = __in6_dev_get(dev);
+	if (in6_dev) {
+		atomic_dec(&in6_dev->cnf.mc_forwarding);
+		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
+					     NETCONFA_MC_FORWARDING,
+					     dev->ifindex, &in6_dev->cnf);
+	}
+
+	if ((v->flags & MIFF_REGISTER) && !notify)
+		unregister_netdevice_queue(dev, head);
+
+	netdev_put(dev, &v->dev_tracker);
+	return 0;
+}
+
+static inline void ip6mr_cache_free_rcu(struct rcu_head *head)
+{
+	struct mr_mfc *c = container_of(head, struct mr_mfc, rcu);
+
+	kmem_cache_free(mrt_cachep, (struct mfc6_cache *)c);
+}
+
+static inline void ip6mr_cache_free(struct mfc6_cache *c)
+{
+	call_rcu(&c->_c.rcu, ip6mr_cache_free_rcu);
+}
+
+/* Destroy an unresolved cache entry, killing queued skbs
+   and reporting error to netlink readers.
+ */
+
+static void ip6mr_destroy_unres(struct mr_table *mrt, struct mfc6_cache *c)
+{
+	struct net *net = read_pnet(&mrt->net);
+	struct sk_buff *skb;
+
+	atomic_dec(&mrt->cache_resolve_queue_len);
+
+	while ((skb = skb_dequeue(&c->_c.mfc_un.unres.unresolved)) != NULL) {
+		if (ipv6_hdr(skb)->version == 0) {
+			struct nlmsghdr *nlh = skb_pull(skb,
+							sizeof(struct ipv6hdr));
+			nlh->nlmsg_type = NLMSG_ERROR;
+			nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
+			skb_trim(skb, nlh->nlmsg_len);
+			((struct nlmsgerr *)nlmsg_data(nlh))->error = -ETIMEDOUT;
+			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
+		} else
+			kfree_skb(skb);
+	}
+
+	ip6mr_cache_free(c);
+}
+
+
+/* Timer process for all the unresolved queue. */
+
+static void ipmr_do_expire_process(struct mr_table *mrt)
+{
+	unsigned long now = jiffies;
+	unsigned long expires = 10 * HZ;
+	struct mr_mfc *c, *next;
+
+	list_for_each_entry_safe(c, next, &mrt->mfc_unres_queue, list) {
+		if (time_after(c->mfc_un.unres.expires, now)) {
+			/* not yet... */
+			unsigned long interval = c->mfc_un.unres.expires - now;
+			if (interval < expires)
+				expires = interval;
+			continue;
+		}
+
+		list_del(&c->list);
+		mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
+		ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
+	}
+
+	if (!list_empty(&mrt->mfc_unres_queue))
+		mod_timer(&mrt->ipmr_expire_timer, jiffies + expires);
+}
+
+static void ipmr_expire_process(struct timer_list *t)
+{
+	struct mr_table *mrt = from_timer(mrt, t, ipmr_expire_timer);
+
+	if (!spin_trylock(&mfc_unres_lock)) {
+		mod_timer(&mrt->ipmr_expire_timer, jiffies + 1);
+		return;
+	}
+
+	if (!list_empty(&mrt->mfc_unres_queue))
+		ipmr_do_expire_process(mrt);
+
+	spin_unlock(&mfc_unres_lock);
+}
+
+/* Fill oifs list. It is called under locked mrt_lock. */
+
+static void ip6mr_update_thresholds(struct mr_table *mrt,
+				    struct mr_mfc *cache,
+				    unsigned char *ttls)
+{
+	int vifi;
+
+	cache->mfc_un.res.minvif = MAXMIFS;
+	cache->mfc_un.res.maxvif = 0;
+	memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
+
+	for (vifi = 0; vifi < mrt->maxvif; vifi++) {
+		if (VIF_EXISTS(mrt, vifi) &&
+		    ttls[vifi] && ttls[vifi] < 255) {
+			cache->mfc_un.res.ttls[vifi] = ttls[vifi];
+			if (cache->mfc_un.res.minvif > vifi)
+				cache->mfc_un.res.minvif = vifi;
+			if (cache->mfc_un.res.maxvif <= vifi)
+				cache->mfc_un.res.maxvif = vifi + 1;
+		}
+	}
+	cache->mfc_un.res.lastuse = jiffies;
+}
+
+static int mif6_add(struct net *net, struct mr_table *mrt,
+		    struct mif6ctl *vifc, int mrtsock)
+{
+	int vifi = vifc->mif6c_mifi;
+	struct vif_device *v = &mrt->vif_table[vifi];
+	struct net_device *dev;
+	struct inet6_dev *in6_dev;
+	int err;
+
+	/* Is vif busy ? */
+	if (VIF_EXISTS(mrt, vifi))
+		return -EADDRINUSE;
+
+	switch (vifc->mif6c_flags) {
+#ifdef CONFIG_IPV6_PIMSM_V2
+	case MIFF_REGISTER:
+		/*
+		 * Special Purpose VIF in PIM
+		 * All the packets will be sent to the daemon
+		 */
+		if (mrt->mroute_reg_vif_num >= 0)
+			return -EADDRINUSE;
+		dev = ip6mr_reg_vif(net, mrt);
+		if (!dev)
+			return -ENOBUFS;
+		err = dev_set_allmulti(dev, 1);
+		if (err) {
+			unregister_netdevice(dev);
+			dev_put(dev);
+			return err;
+		}
+		break;
+#endif
+	case 0:
+		dev = dev_get_by_index(net, vifc->mif6c_pifi);
+		if (!dev)
+			return -EADDRNOTAVAIL;
+		err = dev_set_allmulti(dev, 1);
+		if (err) {
+			dev_put(dev);
+			return err;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	in6_dev = __in6_dev_get(dev);
+	if (in6_dev) {
+		atomic_inc(&in6_dev->cnf.mc_forwarding);
+		inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
+					     NETCONFA_MC_FORWARDING,
+					     dev->ifindex, &in6_dev->cnf);
+	}
+
+	/* Fill in the VIF structures */
+	vif_device_init(v, dev, vifc->vifc_rate_limit, vifc->vifc_threshold,
+			vifc->mif6c_flags | (!mrtsock ? VIFF_STATIC : 0),
+			MIFF_REGISTER);
+
+	/* And finish update writing critical data */
+	spin_lock(&mrt_lock);
+	rcu_assign_pointer(v->dev, dev);
+	netdev_tracker_alloc(dev, &v->dev_tracker, GFP_ATOMIC);
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (v->flags & MIFF_REGISTER)
+		WRITE_ONCE(mrt->mroute_reg_vif_num, vifi);
+#endif
+	if (vifi + 1 > mrt->maxvif)
+		WRITE_ONCE(mrt->maxvif, vifi + 1);
+	spin_unlock(&mrt_lock);
+	call_ip6mr_vif_entry_notifiers(net, FIB_EVENT_VIF_ADD,
+				       v, dev, vifi, mrt->id);
+	return 0;
+}
+
+static struct mfc6_cache *ip6mr_cache_find(struct mr_table *mrt,
+					   const struct in6_addr *origin,
+					   const struct in6_addr *mcastgrp)
+{
+	struct mfc6_cache_cmp_arg arg = {
+		.mf6c_origin = *origin,
+		.mf6c_mcastgrp = *mcastgrp,
+	};
+
+	return mr_mfc_find(mrt, &arg);
+}
+
+/* Look for a (*,G) entry */
+static struct mfc6_cache *ip6mr_cache_find_any(struct mr_table *mrt,
+					       struct in6_addr *mcastgrp,
+					       mifi_t mifi)
+{
+	struct mfc6_cache_cmp_arg arg = {
+		.mf6c_origin = in6addr_any,
+		.mf6c_mcastgrp = *mcastgrp,
+	};
+
+	if (ipv6_addr_any(mcastgrp))
+		return mr_mfc_find_any_parent(mrt, mifi);
+	return mr_mfc_find_any(mrt, mifi, &arg);
+}
+
+/* Look for a (S,G,iif) entry if parent != -1 */
+static struct mfc6_cache *
+ip6mr_cache_find_parent(struct mr_table *mrt,
+			const struct in6_addr *origin,
+			const struct in6_addr *mcastgrp,
+			int parent)
+{
+	struct mfc6_cache_cmp_arg arg = {
+		.mf6c_origin = *origin,
+		.mf6c_mcastgrp = *mcastgrp,
+	};
+
+	return mr_mfc_find_parent(mrt, &arg, parent);
+}
+
+/* Allocate a multicast cache entry */
+static struct mfc6_cache *ip6mr_cache_alloc(void)
+{
+	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
+	if (!c)
+		return NULL;
+	c->_c.mfc_un.res.last_assert = jiffies - MFC_ASSERT_THRESH - 1;
+	c->_c.mfc_un.res.minvif = MAXMIFS;
+	c->_c.free = ip6mr_cache_free_rcu;
+	refcount_set(&c->_c.mfc_un.res.refcount, 1);
+	return c;
+}
+
+static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
+{
+	struct mfc6_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
+	if (!c)
+		return NULL;
+	skb_queue_head_init(&c->_c.mfc_un.unres.unresolved);
+	c->_c.mfc_un.unres.expires = jiffies + 10 * HZ;
+	return c;
+}
+
+/*
+ *	A cache entry has gone into a resolved state from queued
+ */
+
+static void ip6mr_cache_resolve(struct net *net, struct mr_table *mrt,
+				struct mfc6_cache *uc, struct mfc6_cache *c)
+{
+	struct sk_buff *skb;
+
+	/*
+	 *	Play the pending entries through our router
+	 */
+
+	while ((skb = __skb_dequeue(&uc->_c.mfc_un.unres.unresolved))) {
+		if (ipv6_hdr(skb)->version == 0) {
+			struct nlmsghdr *nlh = skb_pull(skb,
+							sizeof(struct ipv6hdr));
+
+			if (mr_fill_mroute(mrt, skb, &c->_c,
+					   nlmsg_data(nlh)) > 0) {
+				nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
+			} else {
+				nlh->nlmsg_type = NLMSG_ERROR;
+				nlh->nlmsg_len = nlmsg_msg_size(sizeof(struct nlmsgerr));
+				skb_trim(skb, nlh->nlmsg_len);
+				((struct nlmsgerr *)nlmsg_data(nlh))->error = -EMSGSIZE;
+			}
+			rtnl_unicast(skb, net, NETLINK_CB(skb).portid);
+		} else {
+			rcu_read_lock();
+			ip6_mr_forward(net, mrt, skb->dev, skb, c);
+			rcu_read_unlock();
+		}
+	}
+}
+
+/*
+ *	Bounce a cache query up to pim6sd and netlink.
+ *
+ *	Called under rcu_read_lock()
+ */
+
+static int ip6mr_cache_report(const struct mr_table *mrt, struct sk_buff *pkt,
+			      mifi_t mifi, int assert)
+{
+	struct sock *mroute6_sk;
+	struct sk_buff *skb;
+	struct mrt6msg *msg;
+	int ret;
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (assert == MRT6MSG_WHOLEPKT || assert == MRT6MSG_WRMIFWHOLE)
+		skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
+						+sizeof(*msg));
+	else
+#endif
+		skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);
+
+	if (!skb)
+		return -ENOBUFS;
+
+	/* I suppose that internal messages
+	 * do not require checksums */
+
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (assert == MRT6MSG_WHOLEPKT || assert == MRT6MSG_WRMIFWHOLE) {
+		/* Ugly, but we have no choice with this interface.
+		   Duplicate old header, fix length etc.
+		   And all this only to mangle msg->im6_msgtype and
+		   to set msg->im6_mbz to "mbz" :-)
+		 */
+		__skb_pull(skb, skb_network_offset(pkt));
+
+		skb_push(skb, sizeof(*msg));
+		skb_reset_transport_header(skb);
+		msg = (struct mrt6msg *)skb_transport_header(skb);
+		msg->im6_mbz = 0;
+		msg->im6_msgtype = assert;
+		if (assert == MRT6MSG_WRMIFWHOLE)
+			msg->im6_mif = mifi;
+		else
+			msg->im6_mif = READ_ONCE(mrt->mroute_reg_vif_num);
+		msg->im6_pad = 0;
+		msg->im6_src = ipv6_hdr(pkt)->saddr;
+		msg->im6_dst = ipv6_hdr(pkt)->daddr;
+
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	} else
+#endif
+	{
+	/*
+	 *	Copy the IP header
+	 */
+
+	skb_put(skb, sizeof(struct ipv6hdr));
+	skb_reset_network_header(skb);
+	skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));
+
+	/*
+	 *	Add our header
+	 */
+	skb_put(skb, sizeof(*msg));
+	skb_reset_transport_header(skb);
+	msg = (struct mrt6msg *)skb_transport_header(skb);
+
+	msg->im6_mbz = 0;
+	msg->im6_msgtype = assert;
+	msg->im6_mif = mifi;
+	msg->im6_pad = 0;
+	msg->im6_src = ipv6_hdr(pkt)->saddr;
+	msg->im6_dst = ipv6_hdr(pkt)->daddr;
+
+	skb_dst_set(skb, dst_clone(skb_dst(pkt)));
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	}
+
+	mroute6_sk = rcu_dereference(mrt->mroute_sk);
+	if (!mroute6_sk) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	mrt6msg_netlink_event(mrt, skb);
+
+	/* Deliver to user space multicast routing algorithms */
+	ret = sock_queue_rcv_skb(mroute6_sk, skb);
+
+	if (ret < 0) {
+		net_warn_ratelimited("mroute6: pending queue full, dropping entries\n");
+		kfree_skb(skb);
+	}
+
+	return ret;
+}
+
+/* Queue a packet for resolution. It gets locked cache entry! */
+static int ip6mr_cache_unresolved(struct mr_table *mrt, mifi_t mifi,
+				  struct sk_buff *skb, struct net_device *dev)
+{
+	struct mfc6_cache *c;
+	bool found = false;
+	int err;
+
+	spin_lock_bh(&mfc_unres_lock);
+	list_for_each_entry(c, &mrt->mfc_unres_queue, _c.list) {
+		if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
+		    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr)) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found) {
+		/*
+		 *	Create a new entry if allowable
+		 */
+
+		c = ip6mr_cache_alloc_unres();
+		if (!c) {
+			spin_unlock_bh(&mfc_unres_lock);
+
+			kfree_skb(skb);
+			return -ENOBUFS;
+		}
+
+		/* Fill in the new cache entry */
+		c->_c.mfc_parent = -1;
+		c->mf6c_origin = ipv6_hdr(skb)->saddr;
+		c->mf6c_mcastgrp = ipv6_hdr(skb)->daddr;
+
+		/*
+		 *	Reflect first query at pim6sd
+		 */
+		err = ip6mr_cache_report(mrt, skb, mifi, MRT6MSG_NOCACHE);
+		if (err < 0) {
+			/* If the report failed throw the cache entry
+			   out - Brad Parker
+			 */
+			spin_unlock_bh(&mfc_unres_lock);
+
+			ip6mr_cache_free(c);
+			kfree_skb(skb);
+			return err;
+		}
+
+		atomic_inc(&mrt->cache_resolve_queue_len);
+		list_add(&c->_c.list, &mrt->mfc_unres_queue);
+		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
+
+		ipmr_do_expire_process(mrt);
+	}
+
+	/* See if we can append the packet */
+	if (c->_c.mfc_un.unres.unresolved.qlen > 3) {
+		kfree_skb(skb);
+		err = -ENOBUFS;
+	} else {
+		if (dev) {
+			skb->dev = dev;
+			skb->skb_iif = dev->ifindex;
+		}
+		skb_queue_tail(&c->_c.mfc_un.unres.unresolved, skb);
+		err = 0;
+	}
+
+	spin_unlock_bh(&mfc_unres_lock);
+	return err;
+}
+
+/*
+ *	MFC6 cache manipulation by user space
+ */
+
+static int ip6mr_mfc_delete(struct mr_table *mrt, struct mf6cctl *mfc,
+			    int parent)
+{
+	struct mfc6_cache *c;
+
+	/* The entries are added/deleted only under RTNL */
+	rcu_read_lock();
+	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
+				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
+	rcu_read_unlock();
+	if (!c)
+		return -ENOENT;
+	rhltable_remove(&mrt->mfc_hash, &c->_c.mnode, ip6mr_rht_params);
+	list_del_rcu(&c->_c.list);
+
+	call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
+				       FIB_EVENT_ENTRY_DEL, c, mrt->id);
+	mr6_netlink_event(mrt, c, RTM_DELROUTE);
+	mr_cache_put(&c->_c);
+	return 0;
+}
+
+static int ip6mr_device_event(struct notifier_block *this,
+			      unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct net *net = dev_net(dev);
+	struct mr_table *mrt;
+	struct vif_device *v;
+	int ct;
+
+	if (event != NETDEV_UNREGISTER)
+		return NOTIFY_DONE;
+
+	ip6mr_for_each_table(mrt, net) {
+		v = &mrt->vif_table[0];
+		for (ct = 0; ct < mrt->maxvif; ct++, v++) {
+			if (rcu_access_pointer(v->dev) == dev)
+				mif6_delete(mrt, ct, 1, NULL);
+		}
+	}
+
+	return NOTIFY_DONE;
+}
+
+static unsigned int ip6mr_seq_read(struct net *net)
+{
+	ASSERT_RTNL();
+
+	return net->ipv6.ipmr_seq + ip6mr_rules_seq_read(net);
+}
+
+static int ip6mr_dump(struct net *net, struct notifier_block *nb,
+		      struct netlink_ext_ack *extack)
+{
+	return mr_dump(net, nb, RTNL_FAMILY_IP6MR, ip6mr_rules_dump,
+		       ip6mr_mr_table_iter, extack);
+}
+
+static struct notifier_block ip6_mr_notifier = {
+	.notifier_call = ip6mr_device_event
+};
+
+static const struct fib_notifier_ops ip6mr_notifier_ops_template = {
+	.family		= RTNL_FAMILY_IP6MR,
+	.fib_seq_read	= ip6mr_seq_read,
+	.fib_dump	= ip6mr_dump,
+	.owner		= THIS_MODULE,
+};
+
+static int __net_init ip6mr_notifier_init(struct net *net)
+{
+	struct fib_notifier_ops *ops;
+
+	net->ipv6.ipmr_seq = 0;
+
+	ops = fib_notifier_ops_register(&ip6mr_notifier_ops_template, net);
+	if (IS_ERR(ops))
+		return PTR_ERR(ops);
+
+	net->ipv6.ip6mr_notifier_ops = ops;
+
+	return 0;
+}
+
+static void __net_exit ip6mr_notifier_exit(struct net *net)
+{
+	fib_notifier_ops_unregister(net->ipv6.ip6mr_notifier_ops);
+	net->ipv6.ip6mr_notifier_ops = NULL;
+}
+
+/* Setup for IP multicast routing */
+static int __net_init ip6mr_net_init(struct net *net)
+{
+	int err;
+
+	err = ip6mr_notifier_init(net);
+	if (err)
+		return err;
+
+	err = ip6mr_rules_init(net);
+	if (err < 0)
+		goto ip6mr_rules_fail;
+
+#ifdef CONFIG_PROC_FS
+	err = -ENOMEM;
+	if (!proc_create_net("ip6_mr_vif", 0, net->proc_net, &ip6mr_vif_seq_ops,
+			sizeof(struct mr_vif_iter)))
+		goto proc_vif_fail;
+	if (!proc_create_net("ip6_mr_cache", 0, net->proc_net, &ipmr_mfc_seq_ops,
+			sizeof(struct mr_mfc_iter)))
+		goto proc_cache_fail;
+#endif
+
+	return 0;
+
+#ifdef CONFIG_PROC_FS
+proc_cache_fail:
+	remove_proc_entry("ip6_mr_vif", net->proc_net);
+proc_vif_fail:
+	rtnl_lock();
+	ip6mr_rules_exit(net);
+	rtnl_unlock();
+#endif
+ip6mr_rules_fail:
+	ip6mr_notifier_exit(net);
+	return err;
+}
+
+static void __net_exit ip6mr_net_exit(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+	remove_proc_entry("ip6_mr_cache", net->proc_net);
+	remove_proc_entry("ip6_mr_vif", net->proc_net);
+#endif
+	ip6mr_notifier_exit(net);
+}
+
+static void __net_exit ip6mr_net_exit_batch(struct list_head *net_list)
+{
+	struct net *net;
+
+	rtnl_lock();
+	list_for_each_entry(net, net_list, exit_list)
+		ip6mr_rules_exit(net);
+	rtnl_unlock();
+}
+
+static struct pernet_operations ip6mr_net_ops = {
+	.init = ip6mr_net_init,
+	.exit = ip6mr_net_exit,
+	.exit_batch = ip6mr_net_exit_batch,
+};
+
+int __init ip6_mr_init(void)
+{
+	int err;
+
+	mrt_cachep = kmem_cache_create("ip6_mrt_cache",
+				       sizeof(struct mfc6_cache),
+				       0, SLAB_HWCACHE_ALIGN,
+				       NULL);
+	if (!mrt_cachep)
+		return -ENOMEM;
+
+	err = register_pernet_subsys(&ip6mr_net_ops);
+	if (err)
+		goto reg_pernet_fail;
+
+	err = register_netdevice_notifier(&ip6_mr_notifier);
+	if (err)
+		goto reg_notif_fail;
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (inet6_add_protocol(&pim6_protocol, IPPROTO_PIM) < 0) {
+		pr_err("%s: can't add PIM protocol\n", __func__);
+		err = -EAGAIN;
+		goto add_proto_fail;
+	}
+#endif
+	err = rtnl_register_module(THIS_MODULE, RTNL_FAMILY_IP6MR, RTM_GETROUTE,
+				   ip6mr_rtm_getroute, ip6mr_rtm_dumproute, 0);
+	if (err == 0)
+		return 0;
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
+add_proto_fail:
+	unregister_netdevice_notifier(&ip6_mr_notifier);
+#endif
+reg_notif_fail:
+	unregister_pernet_subsys(&ip6mr_net_ops);
+reg_pernet_fail:
+	kmem_cache_destroy(mrt_cachep);
+	return err;
+}
+
+void ip6_mr_cleanup(void)
+{
+	rtnl_unregister(RTNL_FAMILY_IP6MR, RTM_GETROUTE);
+#ifdef CONFIG_IPV6_PIMSM_V2
+	inet6_del_protocol(&pim6_protocol, IPPROTO_PIM);
+#endif
+	unregister_netdevice_notifier(&ip6_mr_notifier);
+	unregister_pernet_subsys(&ip6mr_net_ops);
+	kmem_cache_destroy(mrt_cachep);
+}
+
+static int ip6mr_mfc_add(struct net *net, struct mr_table *mrt,
+			 struct mf6cctl *mfc, int mrtsock, int parent)
+{
+	unsigned char ttls[MAXMIFS];
+	struct mfc6_cache *uc, *c;
+	struct mr_mfc *_uc;
+	bool found;
+	int i, err;
+
+	if (mfc->mf6cc_parent >= MAXMIFS)
+		return -ENFILE;
+
+	memset(ttls, 255, MAXMIFS);
+	for (i = 0; i < MAXMIFS; i++) {
+		if (IF_ISSET(i, &mfc->mf6cc_ifset))
+			ttls[i] = 1;
+	}
+
+	/* The entries are added/deleted only under RTNL */
+	rcu_read_lock();
+	c = ip6mr_cache_find_parent(mrt, &mfc->mf6cc_origin.sin6_addr,
+				    &mfc->mf6cc_mcastgrp.sin6_addr, parent);
+	rcu_read_unlock();
+	if (c) {
+		spin_lock(&mrt_lock);
+		c->_c.mfc_parent = mfc->mf6cc_parent;
+		ip6mr_update_thresholds(mrt, &c->_c, ttls);
+		if (!mrtsock)
+			c->_c.mfc_flags |= MFC_STATIC;
+		spin_unlock(&mrt_lock);
+		call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE,
+					       c, mrt->id);
+		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
+		return 0;
+	}
+
+	if (!ipv6_addr_any(&mfc->mf6cc_mcastgrp.sin6_addr) &&
+	    !ipv6_addr_is_multicast(&mfc->mf6cc_mcastgrp.sin6_addr))
+		return -EINVAL;
+
+	c = ip6mr_cache_alloc();
+	if (!c)
+		return -ENOMEM;
+
+	c->mf6c_origin = mfc->mf6cc_origin.sin6_addr;
+	c->mf6c_mcastgrp = mfc->mf6cc_mcastgrp.sin6_addr;
+	c->_c.mfc_parent = mfc->mf6cc_parent;
+	ip6mr_update_thresholds(mrt, &c->_c, ttls);
+	if (!mrtsock)
+		c->_c.mfc_flags |= MFC_STATIC;
+
+	err = rhltable_insert_key(&mrt->mfc_hash, &c->cmparg, &c->_c.mnode,
+				  ip6mr_rht_params);
+	if (err) {
+		pr_err("ip6mr: rhtable insert error %d\n", err);
+		ip6mr_cache_free(c);
+		return err;
+	}
+	list_add_tail_rcu(&c->_c.list, &mrt->mfc_cache_list);
+
+	/* Check to see if we resolved a queued list. If so we
+	 * need to send on the frames and tidy up.
+	 */
+	found = false;
+	spin_lock_bh(&mfc_unres_lock);
+	list_for_each_entry(_uc, &mrt->mfc_unres_queue, list) {
+		uc = (struct mfc6_cache *)_uc;
+		if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&
+		    ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {
+			list_del(&_uc->list);
+			atomic_dec(&mrt->cache_resolve_queue_len);
+			found = true;
+			break;
+		}
+	}
+	if (list_empty(&mrt->mfc_unres_queue))
+		del_timer(&mrt->ipmr_expire_timer);
+	spin_unlock_bh(&mfc_unres_lock);
+
+	if (found) {
+		ip6mr_cache_resolve(net, mrt, uc, c);
+		ip6mr_cache_free(uc);
+	}
+	call_ip6mr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_ADD,
+				       c, mrt->id);
+	mr6_netlink_event(mrt, c, RTM_NEWROUTE);
+	return 0;
+}
+
+/*
+ *	Close the multicast socket, and clear the vif tables etc
+ */
+
+static void mroute_clean_tables(struct mr_table *mrt, int flags)
+{
+	struct mr_mfc *c, *tmp;
+	LIST_HEAD(list);
+	int i;
+
+	/* Shut down all active vif entries */
+	if (flags & (MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC)) {
+		for (i = 0; i < mrt->maxvif; i++) {
+			if (((mrt->vif_table[i].flags & VIFF_STATIC) &&
+			     !(flags & MRT6_FLUSH_MIFS_STATIC)) ||
+			    (!(mrt->vif_table[i].flags & VIFF_STATIC) && !(flags & MRT6_FLUSH_MIFS)))
+				continue;
+			mif6_delete(mrt, i, 0, &list);
+		}
+		unregister_netdevice_many(&list);
+	}
+
+	/* Wipe the cache */
+	if (flags & (MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC)) {
+		list_for_each_entry_safe(c, tmp, &mrt->mfc_cache_list, list) {
+			if (((c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC_STATIC)) ||
+			    (!(c->mfc_flags & MFC_STATIC) && !(flags & MRT6_FLUSH_MFC)))
+				continue;
+			rhltable_remove(&mrt->mfc_hash, &c->mnode, ip6mr_rht_params);
+			list_del_rcu(&c->list);
+			call_ip6mr_mfc_entry_notifiers(read_pnet(&mrt->net),
+						       FIB_EVENT_ENTRY_DEL,
+						       (struct mfc6_cache *)c, mrt->id);
+			mr6_netlink_event(mrt, (struct mfc6_cache *)c, RTM_DELROUTE);
+			mr_cache_put(c);
+		}
+	}
+
+	if (flags & MRT6_FLUSH_MFC) {
+		if (atomic_read(&mrt->cache_resolve_queue_len) != 0) {
+			spin_lock_bh(&mfc_unres_lock);
+			list_for_each_entry_safe(c, tmp, &mrt->mfc_unres_queue, list) {
+				list_del(&c->list);
+				mr6_netlink_event(mrt, (struct mfc6_cache *)c,
+						  RTM_DELROUTE);
+				ip6mr_destroy_unres(mrt, (struct mfc6_cache *)c);
+			}
+			spin_unlock_bh(&mfc_unres_lock);
+		}
+	}
+}
+
+static int ip6mr_sk_init(struct mr_table *mrt, struct sock *sk)
+{
+	int err = 0;
+	struct net *net = sock_net(sk);
+
+	rtnl_lock();
+	spin_lock(&mrt_lock);
+	if (rtnl_dereference(mrt->mroute_sk)) {
+		err = -EADDRINUSE;
+	} else {
+		rcu_assign_pointer(mrt->mroute_sk, sk);
+		sock_set_flag(sk, SOCK_RCU_FREE);
+		atomic_inc(&net->ipv6.devconf_all->mc_forwarding);
+	}
+	spin_unlock(&mrt_lock);
+
+	if (!err)
+		inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
+					     NETCONFA_MC_FORWARDING,
+					     NETCONFA_IFINDEX_ALL,
+					     net->ipv6.devconf_all);
+	rtnl_unlock();
+
+	return err;
+}
+
+int ip6mr_sk_done(struct sock *sk)
+{
+	struct net *net = sock_net(sk);
+	struct ipv6_devconf *devconf;
+	struct mr_table *mrt;
+	int err = -EACCES;
+
+	if (sk->sk_type != SOCK_RAW ||
+	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
+		return err;
+
+	devconf = net->ipv6.devconf_all;
+	if (!devconf || !atomic_read(&devconf->mc_forwarding))
+		return err;
+
+	rtnl_lock();
+	ip6mr_for_each_table(mrt, net) {
+		if (sk == rtnl_dereference(mrt->mroute_sk)) {
+			spin_lock(&mrt_lock);
+			RCU_INIT_POINTER(mrt->mroute_sk, NULL);
+			/* Note that mroute_sk had SOCK_RCU_FREE set,
+			 * so the RCU grace period before sk freeing
+			 * is guaranteed by sk_destruct()
+			 */
+			atomic_dec(&devconf->mc_forwarding);
+			spin_unlock(&mrt_lock);
+			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
+						     NETCONFA_MC_FORWARDING,
+						     NETCONFA_IFINDEX_ALL,
+						     net->ipv6.devconf_all);
+
+			mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MFC);
+			err = 0;
+			break;
+		}
+	}
+	rtnl_unlock();
+
+	return err;
+}
+
+bool mroute6_is_socket(struct net *net, struct sk_buff *skb)
+{
+	struct mr_table *mrt;
+	struct flowi6 fl6 = {
+		.flowi6_iif	= skb->skb_iif ? : LOOPBACK_IFINDEX,
+		.flowi6_oif	= skb->dev->ifindex,
+		.flowi6_mark	= skb->mark,
+	};
+
+	if (ip6mr_fib_lookup(net, &fl6, &mrt) < 0)
+		return NULL;
+
+	return rcu_access_pointer(mrt->mroute_sk);
+}
+EXPORT_SYMBOL(mroute6_is_socket);
+
+/*
+ *	Socket options and virtual interface manipulation. The whole
+ *	virtual interface system is a complete heap, but unfortunately
+ *	that's how BSD mrouted happens to think. Maybe one day with a proper
+ *	MOSPF/PIM router set up we can clean this up.
+ */
+
+int ip6_mroute_setsockopt(struct sock *sk, int optname, sockptr_t optval,
+			  unsigned int optlen)
+{
+	int ret, parent = 0;
+	struct mif6ctl vif;
+	struct mf6cctl mfc;
+	mifi_t mifi;
+	struct net *net = sock_net(sk);
+	struct mr_table *mrt;
+
+	if (sk->sk_type != SOCK_RAW ||
+	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
+		return -EOPNOTSUPP;
+
+	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
+	if (!mrt)
+		return -ENOENT;
+
+	if (optname != MRT6_INIT) {
+		if (sk != rcu_access_pointer(mrt->mroute_sk) &&
+		    !ns_capable(net->user_ns, CAP_NET_ADMIN))
+			return -EACCES;
+	}
+
+	switch (optname) {
+	case MRT6_INIT:
+		if (optlen < sizeof(int))
+			return -EINVAL;
+
+		return ip6mr_sk_init(mrt, sk);
+
+	case MRT6_DONE:
+		return ip6mr_sk_done(sk);
+
+	case MRT6_ADD_MIF:
+		if (optlen < sizeof(vif))
+			return -EINVAL;
+		if (copy_from_sockptr(&vif, optval, sizeof(vif)))
+			return -EFAULT;
+		if (vif.mif6c_mifi >= MAXMIFS)
+			return -ENFILE;
+		rtnl_lock();
+		ret = mif6_add(net, mrt, &vif,
+			       sk == rtnl_dereference(mrt->mroute_sk));
+		rtnl_unlock();
+		return ret;
+
+	case MRT6_DEL_MIF:
+		if (optlen < sizeof(mifi_t))
+			return -EINVAL;
+		if (copy_from_sockptr(&mifi, optval, sizeof(mifi_t)))
+			return -EFAULT;
+		rtnl_lock();
+		ret = mif6_delete(mrt, mifi, 0, NULL);
+		rtnl_unlock();
+		return ret;
+
+	/*
+	 *	Manipulate the forwarding caches. These live
+	 *	in a sort of kernel/user symbiosis.
+	 */
+	case MRT6_ADD_MFC:
+	case MRT6_DEL_MFC:
+		parent = -1;
+		fallthrough;
+	case MRT6_ADD_MFC_PROXY:
+	case MRT6_DEL_MFC_PROXY:
+		if (optlen < sizeof(mfc))
+			return -EINVAL;
+		if (copy_from_sockptr(&mfc, optval, sizeof(mfc)))
+			return -EFAULT;
+		if (parent == 0)
+			parent = mfc.mf6cc_parent;
+		rtnl_lock();
+		if (optname == MRT6_DEL_MFC || optname == MRT6_DEL_MFC_PROXY)
+			ret = ip6mr_mfc_delete(mrt, &mfc, parent);
+		else
+			ret = ip6mr_mfc_add(net, mrt, &mfc,
+					    sk ==
+					    rtnl_dereference(mrt->mroute_sk),
+					    parent);
+		rtnl_unlock();
+		return ret;
+
+	case MRT6_FLUSH:
+	{
+		int flags;
+
+		if (optlen != sizeof(flags))
+			return -EINVAL;
+		if (copy_from_sockptr(&flags, optval, sizeof(flags)))
+			return -EFAULT;
+		rtnl_lock();
+		mroute_clean_tables(mrt, flags);
+		rtnl_unlock();
+		return 0;
+	}
+
+	/*
+	 *	Control PIM assert (to activate pim will activate assert)
+	 */
+	case MRT6_ASSERT:
+	{
+		int v;
+
+		if (optlen != sizeof(v))
+			return -EINVAL;
+		if (copy_from_sockptr(&v, optval, sizeof(v)))
+			return -EFAULT;
+		mrt->mroute_do_assert = v;
+		return 0;
+	}
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	case MRT6_PIM:
+	{
+		bool do_wrmifwhole;
+		int v;
+
+		if (optlen != sizeof(v))
+			return -EINVAL;
+		if (copy_from_sockptr(&v, optval, sizeof(v)))
+			return -EFAULT;
+
+		do_wrmifwhole = (v == MRT6MSG_WRMIFWHOLE);
+		v = !!v;
+		rtnl_lock();
+		ret = 0;
+		if (v != mrt->mroute_do_pim) {
+			mrt->mroute_do_pim = v;
+			mrt->mroute_do_assert = v;
+			mrt->mroute_do_wrvifwhole = do_wrmifwhole;
+		}
+		rtnl_unlock();
+		return ret;
+	}
+
+#endif
+#ifdef CONFIG_IPV6_MROUTE_MULTIPLE_TABLES
+	case MRT6_TABLE:
+	{
+		u32 v;
+
+		if (optlen != sizeof(u32))
+			return -EINVAL;
+		if (copy_from_sockptr(&v, optval, sizeof(v)))
+			return -EFAULT;
+		/* "pim6reg%u" should not exceed 16 bytes (IFNAMSIZ) */
+		if (v != RT_TABLE_DEFAULT && v >= 100000000)
+			return -EINVAL;
+		if (sk == rcu_access_pointer(mrt->mroute_sk))
+			return -EBUSY;
+
+		rtnl_lock();
+		ret = 0;
+		mrt = ip6mr_new_table(net, v);
+		if (IS_ERR(mrt))
+			ret = PTR_ERR(mrt);
+		else
+			raw6_sk(sk)->ip6mr_table = v;
+		rtnl_unlock();
+		return ret;
+	}
+#endif
+	/*
+	 *	Spurious command, or MRT6_VERSION which you cannot
+	 *	set.
+	 */
+	default:
+		return -ENOPROTOOPT;
+	}
+}
+
+/*
+ *	Getsock opt support for the multicast routing system.
+ */
+
+int ip6_mroute_getsockopt(struct sock *sk, int optname, sockptr_t optval,
+			  sockptr_t optlen)
+{
+	int olr;
+	int val;
+	struct net *net = sock_net(sk);
+	struct mr_table *mrt;
+
+	if (sk->sk_type != SOCK_RAW ||
+	    inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
+		return -EOPNOTSUPP;
+
+	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
+	if (!mrt)
+		return -ENOENT;
+
+	switch (optname) {
+	case MRT6_VERSION:
+		val = 0x0305;
+		break;
+#ifdef CONFIG_IPV6_PIMSM_V2
+	case MRT6_PIM:
+		val = mrt->mroute_do_pim;
+		break;
+#endif
+	case MRT6_ASSERT:
+		val = mrt->mroute_do_assert;
+		break;
+	default:
+		return -ENOPROTOOPT;
+	}
+
+	if (copy_from_sockptr(&olr, optlen, sizeof(int)))
+		return -EFAULT;
+
+	olr = min_t(int, olr, sizeof(int));
+	if (olr < 0)
+		return -EINVAL;
+
+	if (copy_to_sockptr(optlen, &olr, sizeof(int)))
+		return -EFAULT;
+	if (copy_to_sockptr(optval, &val, olr))
+		return -EFAULT;
+	return 0;
+}
+
+/*
+ *	The IP multicast ioctl support routines.
+ */
+int ip6mr_ioctl(struct sock *sk, int cmd, void *arg)
+{
+	struct sioc_sg_req6 *sr;
+	struct sioc_mif_req6 *vr;
+	struct vif_device *vif;
+	struct mfc6_cache *c;
+	struct net *net = sock_net(sk);
+	struct mr_table *mrt;
+
+	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
+	if (!mrt)
+		return -ENOENT;
+
+	switch (cmd) {
+	case SIOCGETMIFCNT_IN6:
+		vr = (struct sioc_mif_req6 *)arg;
+		if (vr->mifi >= mrt->maxvif)
+			return -EINVAL;
+		vr->mifi = array_index_nospec(vr->mifi, mrt->maxvif);
+		rcu_read_lock();
+		vif = &mrt->vif_table[vr->mifi];
+		if (VIF_EXISTS(mrt, vr->mifi)) {
+			vr->icount = READ_ONCE(vif->pkt_in);
+			vr->ocount = READ_ONCE(vif->pkt_out);
+			vr->ibytes = READ_ONCE(vif->bytes_in);
+			vr->obytes = READ_ONCE(vif->bytes_out);
+			rcu_read_unlock();
+			return 0;
+		}
+		rcu_read_unlock();
+		return -EADDRNOTAVAIL;
+	case SIOCGETSGCNT_IN6:
+		sr = (struct sioc_sg_req6 *)arg;
+
+		rcu_read_lock();
+		c = ip6mr_cache_find(mrt, &sr->src.sin6_addr,
+				     &sr->grp.sin6_addr);
+		if (c) {
+			sr->pktcnt = c->_c.mfc_un.res.pkt;
+			sr->bytecnt = c->_c.mfc_un.res.bytes;
+			sr->wrong_if = c->_c.mfc_un.res.wrong_if;
+			rcu_read_unlock();
+			return 0;
+		}
+		rcu_read_unlock();
+		return -EADDRNOTAVAIL;
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+struct compat_sioc_sg_req6 {
+	struct sockaddr_in6 src;
+	struct sockaddr_in6 grp;
+	compat_ulong_t pktcnt;
+	compat_ulong_t bytecnt;
+	compat_ulong_t wrong_if;
+};
+
+struct compat_sioc_mif_req6 {
+	mifi_t	mifi;
+	compat_ulong_t icount;
+	compat_ulong_t ocount;
+	compat_ulong_t ibytes;
+	compat_ulong_t obytes;
+};
+
+int ip6mr_compat_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
+{
+	struct compat_sioc_sg_req6 sr;
+	struct compat_sioc_mif_req6 vr;
+	struct vif_device *vif;
+	struct mfc6_cache *c;
+	struct net *net = sock_net(sk);
+	struct mr_table *mrt;
+
+	mrt = ip6mr_get_table(net, raw6_sk(sk)->ip6mr_table ? : RT6_TABLE_DFLT);
+	if (!mrt)
+		return -ENOENT;
+
+	switch (cmd) {
+	case SIOCGETMIFCNT_IN6:
+		if (copy_from_user(&vr, arg, sizeof(vr)))
+			return -EFAULT;
+		if (vr.mifi >= mrt->maxvif)
+			return -EINVAL;
+		vr.mifi = array_index_nospec(vr.mifi, mrt->maxvif);
+		rcu_read_lock();
+		vif = &mrt->vif_table[vr.mifi];
+		if (VIF_EXISTS(mrt, vr.mifi)) {
+			vr.icount = READ_ONCE(vif->pkt_in);
+			vr.ocount = READ_ONCE(vif->pkt_out);
+			vr.ibytes = READ_ONCE(vif->bytes_in);
+			vr.obytes = READ_ONCE(vif->bytes_out);
+			rcu_read_unlock();
+
+			if (copy_to_user(arg, &vr, sizeof(vr)))
+				return -EFAULT;
+			return 0;
+		}
+		rcu_read_unlock();
+		return -EADDRNOTAVAIL;
+	case SIOCGETSGCNT_IN6:
+		if (copy_from_user(&sr, arg, sizeof(sr)))
+			return -EFAULT;
+
+		rcu_read_lock();
+		c = ip6mr_cache_find(mrt, &sr.src.sin6_addr, &sr.grp.sin6_addr);
+		if (c) {
+			sr.pktcnt = c->_c.mfc_un.res.pkt;
+			sr.bytecnt = c->_c.mfc_un.res.bytes;
+			sr.wrong_if = c->_c.mfc_un.res.wrong_if;
+			rcu_read_unlock();
+
+			if (copy_to_user(arg, &sr, sizeof(sr)))
+				return -EFAULT;
+			return 0;
+		}
+		rcu_read_unlock();
+		return -EADDRNOTAVAIL;
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+#endif
+
+static inline int ip6mr_forward2_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
+		      IPSTATS_MIB_OUTFORWDATAGRAMS);
+	return dst_output(net, sk, skb);
+}
+
+/*
+ *	Processing handlers for ip6mr_forward
+ */
+
+static int ip6mr_forward2(struct net *net, struct mr_table *mrt,
+			  struct sk_buff *skb, int vifi)
+{
+	struct vif_device *vif = &mrt->vif_table[vifi];
+	struct net_device *vif_dev;
+	struct ipv6hdr *ipv6h;
+	struct dst_entry *dst;
+	struct flowi6 fl6;
+
+	vif_dev = vif_dev_read(vif);
+	if (!vif_dev)
+		goto out_free;
+
+#ifdef CONFIG_IPV6_PIMSM_V2
+	if (vif->flags & MIFF_REGISTER) {
+		WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
+		WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
+		DEV_STATS_ADD(vif_dev, tx_bytes, skb->len);
+		DEV_STATS_INC(vif_dev, tx_packets);
+		ip6mr_cache_report(mrt, skb, vifi, MRT6MSG_WHOLEPKT);
+		goto out_free;
+	}
+#endif
+
+	ipv6h = ipv6_hdr(skb);
+
+	fl6 = (struct flowi6) {
+		.flowi6_oif = vif->link,
+		.daddr = ipv6h->daddr,
+	};
+
+	dst = ip6_route_output(net, NULL, &fl6);
+	if (dst->error) {
+		dst_release(dst);
+		goto out_free;
+	}
+
+	skb_dst_drop(skb);
+	skb_dst_set(skb, dst);
+
+	/*
+	 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
+	 * not only before forwarding, but after forwarding on all output
+	 * interfaces. It is clear, if mrouter runs a multicasting
+	 * program, it should receive packets not depending to what interface
+	 * program is joined.
+	 * If we will not make it, the program will have to join on all
+	 * interfaces. On the other hand, multihoming host (or router, but
+	 * not mrouter) cannot join to more than one interface - it will
+	 * result in receiving multiple packets.
+	 */
+	skb->dev = vif_dev;
+	WRITE_ONCE(vif->pkt_out, vif->pkt_out + 1);
+	WRITE_ONCE(vif->bytes_out, vif->bytes_out + skb->len);
+
+	/* We are about to write */
+	/* XXX: extension headers? */
+	if (skb_cow(skb, sizeof(*ipv6h) + LL_RESERVED_SPACE(vif_dev)))
+		goto out_free;
+
+	ipv6h = ipv6_hdr(skb);
+	ipv6h->hop_limit--;
+
+	IP6CB(skb)->flags |= IP6SKB_FORWARDED;
+
+	return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
+		       net, NULL, skb, skb->dev, vif_dev,
+		       ip6mr_forward2_finish);
+
+out_free:
+	kfree_skb(skb);
+	return 0;
+}
+
+/* Called with rcu_read_lock() */
+static int ip6mr_find_vif(struct mr_table *mrt, struct net_device *dev)
+{
+	int ct;
+
+	/* Pairs with WRITE_ONCE() in mif6_delete()/mif6_add() */
+	for (ct = READ_ONCE(mrt->maxvif) - 1; ct >= 0; ct--) {
+		if (rcu_access_pointer(mrt->vif_table[ct].dev) == dev)
+			break;
+	}
+	return ct;
+}
+
+/* Called under rcu_read_lock() */
+static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
+			   struct net_device *dev, struct sk_buff *skb,
+			   struct mfc6_cache *c)
+{
+	int psend = -1;
+	int vif, ct;
+	int true_vifi = ip6mr_find_vif(mrt, dev);
+
+	vif = c->_c.mfc_parent;
+	c->_c.mfc_un.res.pkt++;
+	c->_c.mfc_un.res.bytes += skb->len;
+	c->_c.mfc_un.res.lastuse = jiffies;
+
+	if (ipv6_addr_any(&c->mf6c_origin) && true_vifi >= 0) {
+		struct mfc6_cache *cache_proxy;
+
+		/* For an (*,G) entry, we only check that the incoming
+		 * interface is part of the static tree.
+		 */
+		cache_proxy = mr_mfc_find_any_parent(mrt, vif);
+		if (cache_proxy &&
+		    cache_proxy->_c.mfc_un.res.ttls[true_vifi] < 255)
+			goto forward;
+	}
+
+	/*
+	 * Wrong interface: drop packet and (maybe) send PIM assert.
+	 */
+	if (rcu_access_pointer(mrt->vif_table[vif].dev) != dev) {
+		c->_c.mfc_un.res.wrong_if++;
+
+		if (true_vifi >= 0 && mrt->mroute_do_assert &&
+		    /* pimsm uses asserts, when switching from RPT to SPT,
+		       so that we cannot check that packet arrived on an oif.
+		       It is bad, but otherwise we would need to move pretty
+		       large chunk of pimd to kernel. Ough... --ANK
+		     */
+		    (mrt->mroute_do_pim ||
+		     c->_c.mfc_un.res.ttls[true_vifi] < 255) &&
+		    time_after(jiffies,
+			       c->_c.mfc_un.res.last_assert +
+			       MFC_ASSERT_THRESH)) {
+			c->_c.mfc_un.res.last_assert = jiffies;
+			ip6mr_cache_report(mrt, skb, true_vifi, MRT6MSG_WRONGMIF);
+			if (mrt->mroute_do_wrvifwhole)
+				ip6mr_cache_report(mrt, skb, true_vifi,
+						   MRT6MSG_WRMIFWHOLE);
+		}
+		goto dont_forward;
+	}
+
+forward:
+	WRITE_ONCE(mrt->vif_table[vif].pkt_in,
+		   mrt->vif_table[vif].pkt_in + 1);
+	WRITE_ONCE(mrt->vif_table[vif].bytes_in,
+		   mrt->vif_table[vif].bytes_in + skb->len);
+
+	/*
+	 *	Forward the frame
+	 */
+	if (ipv6_addr_any(&c->mf6c_origin) &&
+	    ipv6_addr_any(&c->mf6c_mcastgrp)) {
+		if (true_vifi >= 0 &&
+		    true_vifi != c->_c.mfc_parent &&
+		    ipv6_hdr(skb)->hop_limit >
+				c->_c.mfc_un.res.ttls[c->_c.mfc_parent]) {
+			/* It's an (*,*) entry and the packet is not coming from
+			 * the upstream: forward the packet to the upstream
+			 * only.
+			 */
+			psend = c->_c.mfc_parent;
+			goto last_forward;
+		}
+		goto dont_forward;
+	}
+	for (ct = c->_c.mfc_un.res.maxvif - 1;
+	     ct >= c->_c.mfc_un.res.minvif; ct--) {
+		/* For (*,G) entry, don't forward to the incoming interface */
+		if ((!ipv6_addr_any(&c->mf6c_origin) || ct != true_vifi) &&
+		    ipv6_hdr(skb)->hop_limit > c->_c.mfc_un.res.ttls[ct]) {
+			if (psend != -1) {
+				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
+				if (skb2)
+					ip6mr_forward2(net, mrt, skb2, psend);
+			}
+			psend = ct;
+		}
+	}
+last_forward:
+	if (psend != -1) {
+		ip6mr_forward2(net, mrt, skb, psend);
+		return;
+	}
+
+dont_forward:
+	kfree_skb(skb);
+}
+
+
+/*
+ *	Multicast packets for forwarding arrive here
+ */
+
+int ip6_mr_input(struct sk_buff *skb)
+{
+	struct mfc6_cache *cache;
+	struct net *net = dev_net(skb->dev);
+	struct mr_table *mrt;
+	struct flowi6 fl6 = {
+		.flowi6_iif	= skb->dev->ifindex,
+		.flowi6_mark	= skb->mark,
+	};
+	int err;
+	struct net_device *dev;
+
+	/* skb->dev passed in is the master dev for vrfs.
+	 * Get the proper interface that does have a vif associated with it.
+	 */
+	dev = skb->dev;
+	if (netif_is_l3_master(skb->dev)) {
+		dev = dev_get_by_index_rcu(net, IPCB(skb)->iif);
+		if (!dev) {
+			kfree_skb(skb);
+			return -ENODEV;
+		}
+	}
+
+	err = ip6mr_fib_lookup(net, &fl6, &mrt);
+	if (err < 0) {
+		kfree_skb(skb);
+		return err;
+	}
+
+	cache = ip6mr_cache_find(mrt,
+				 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr);
+	if (!cache) {
+		int vif = ip6mr_find_vif(mrt, dev);
+
+		if (vif >= 0)
+			cache = ip6mr_cache_find_any(mrt,
+						     &ipv6_hdr(skb)->daddr,
+						     vif);
+	}
+
+	/*
+	 *	No usable cache entry
+	 */
+	if (!cache) {
+		int vif;
+
+		vif = ip6mr_find_vif(mrt, dev);
+		if (vif >= 0) {
+			int err = ip6mr_cache_unresolved(mrt, vif, skb, dev);
+
+			return err;
+		}
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	ip6_mr_forward(net, mrt, dev, skb, cache);
+
+	return 0;
+}
+
+int ip6mr_get_route(struct net *net, struct sk_buff *skb, struct rtmsg *rtm,
+		    u32 portid)
+{
+	int err;
+	struct mr_table *mrt;
+	struct mfc6_cache *cache;
+	struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
+
+	mrt = ip6mr_get_table(net, RT6_TABLE_DFLT);
+	if (!mrt)
+		return -ENOENT;
+
+	rcu_read_lock();
+	cache = ip6mr_cache_find(mrt, &rt->rt6i_src.addr, &rt->rt6i_dst.addr);
+	if (!cache && skb->dev) {
+		int vif = ip6mr_find_vif(mrt, skb->dev);
+
+		if (vif >= 0)
+			cache = ip6mr_cache_find_any(mrt, &rt->rt6i_dst.addr,
+						     vif);
+	}
+
+	if (!cache) {
+		struct sk_buff *skb2;
+		struct ipv6hdr *iph;
+		struct net_device *dev;
+		int vif;
+
+		dev = skb->dev;
+		if (!dev || (vif = ip6mr_find_vif(mrt, dev)) < 0) {
+			rcu_read_unlock();
+			return -ENODEV;
+		}
+
+		/* really correct? */
+		skb2 = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
+		if (!skb2) {
+			rcu_read_unlock();
+			return -ENOMEM;
+		}
+
+		NETLINK_CB(skb2).portid = portid;
+		skb_reset_transport_header(skb2);
+
+		skb_put(skb2, sizeof(struct ipv6hdr));
+		skb_reset_network_header(skb2);
+
+		iph = ipv6_hdr(skb2);
+		iph->version = 0;
+		iph->priority = 0;
+		iph->flow_lbl[0] = 0;
+		iph->flow_lbl[1] = 0;
+		iph->flow_lbl[2] = 0;
+		iph->payload_len = 0;
+		iph->nexthdr = IPPROTO_NONE;
+		iph->hop_limit = 0;
+		iph->saddr = rt->rt6i_src.addr;
+		iph->daddr = rt->rt6i_dst.addr;
+
+		err = ip6mr_cache_unresolved(mrt, vif, skb2, dev);
+		rcu_read_unlock();
+
+		return err;
+	}
+
+	err = mr_fill_mroute(mrt, skb, &cache->_c, rtm);
+	rcu_read_unlock();
+	return err;
+}
+
+static int ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
+			     u32 portid, u32 seq, struct mfc6_cache *c, int cmd,
+			     int flags)
+{
+	struct nlmsghdr *nlh;
+	struct rtmsg *rtm;
+	int err;
+
+	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), flags);
+	if (!nlh)
+		return -EMSGSIZE;
+
+	rtm = nlmsg_data(nlh);
+	rtm->rtm_family   = RTNL_FAMILY_IP6MR;
+	rtm->rtm_dst_len  = 128;
+	rtm->rtm_src_len  = 128;
+	rtm->rtm_tos      = 0;
+	rtm->rtm_table    = mrt->id;
+	if (nla_put_u32(skb, RTA_TABLE, mrt->id))
+		goto nla_put_failure;
+	rtm->rtm_type = RTN_MULTICAST;
+	rtm->rtm_scope    = RT_SCOPE_UNIVERSE;
+	if (c->_c.mfc_flags & MFC_STATIC)
+		rtm->rtm_protocol = RTPROT_STATIC;
+	else
+		rtm->rtm_protocol = RTPROT_MROUTED;
+	rtm->rtm_flags    = 0;
+
+	if (nla_put_in6_addr(skb, RTA_SRC, &c->mf6c_origin) ||
+	    nla_put_in6_addr(skb, RTA_DST, &c->mf6c_mcastgrp))
+		goto nla_put_failure;
+	err = mr_fill_mroute(mrt, skb, &c->_c, rtm);
+	/* do not break the dump if cache is unresolved */
+	if (err < 0 && err != -ENOENT)
+		goto nla_put_failure;
+
+	nlmsg_end(skb, nlh);
+	return 0;
+
+nla_put_failure:
+	nlmsg_cancel(skb, nlh);
+	return -EMSGSIZE;
+}
+
+static int _ip6mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
+			      u32 portid, u32 seq, struct mr_mfc *c,
+			      int cmd, int flags)
+{
+	return ip6mr_fill_mroute(mrt, skb, portid, seq, (struct mfc6_cache *)c,
+				 cmd, flags);
+}
+
+static int mr6_msgsize(bool unresolved, int maxvif)
+{
+	size_t len =
+		NLMSG_ALIGN(sizeof(struct rtmsg))
+		+ nla_total_size(4)	/* RTA_TABLE */
+		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_SRC */
+		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_DST */
+		;
+
+	if (!unresolved)
+		len = len
+		      + nla_total_size(4)	/* RTA_IIF */
+		      + nla_total_size(0)	/* RTA_MULTIPATH */
+		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
+						/* RTA_MFC_STATS */
+		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
+		;
+
+	return len;
+}
+
+static void mr6_netlink_event(struct mr_table *mrt, struct mfc6_cache *mfc,
+			      int cmd)
+{
+	struct net *net = read_pnet(&mrt->net);
+	struct sk_buff *skb;
+	int err = -ENOBUFS;
+
+	skb = nlmsg_new(mr6_msgsize(mfc->_c.mfc_parent >= MAXMIFS, mrt->maxvif),
+			GFP_ATOMIC);
+	if (!skb)
+		goto errout;
+
+	err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd, 0);
+	if (err < 0)
+		goto errout;
+
+	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
+	return;
+
+errout:
+	kfree_skb(skb);
+	if (err < 0)
+		rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
+}
+
+static size_t mrt6msg_netlink_msgsize(size_t payloadlen)
+{
+	size_t len =
+		NLMSG_ALIGN(sizeof(struct rtgenmsg))
+		+ nla_total_size(1)	/* IP6MRA_CREPORT_MSGTYPE */
+		+ nla_total_size(4)	/* IP6MRA_CREPORT_MIF_ID */
+					/* IP6MRA_CREPORT_SRC_ADDR */
+		+ nla_total_size(sizeof(struct in6_addr))
+					/* IP6MRA_CREPORT_DST_ADDR */
+		+ nla_total_size(sizeof(struct in6_addr))
+					/* IP6MRA_CREPORT_PKT */
+		+ nla_total_size(payloadlen)
+		;
+
+	return len;
+}
+
+static void mrt6msg_netlink_event(const struct mr_table *mrt, struct sk_buff *pkt)
+{
+	struct net *net = read_pnet(&mrt->net);
+	struct nlmsghdr *nlh;
+	struct rtgenmsg *rtgenm;
+	struct mrt6msg *msg;
+	struct sk_buff *skb;
+	struct nlattr *nla;
+	int payloadlen;
+
+	payloadlen = pkt->len - sizeof(struct mrt6msg);
+	msg = (struct mrt6msg *)skb_transport_header(pkt);
+
+	skb = nlmsg_new(mrt6msg_netlink_msgsize(payloadlen), GFP_ATOMIC);
+	if (!skb)
+		goto errout;
+
+	nlh = nlmsg_put(skb, 0, 0, RTM_NEWCACHEREPORT,
+			sizeof(struct rtgenmsg), 0);
+	if (!nlh)
+		goto errout;
+	rtgenm = nlmsg_data(nlh);
+	rtgenm->rtgen_family = RTNL_FAMILY_IP6MR;
+	if (nla_put_u8(skb, IP6MRA_CREPORT_MSGTYPE, msg->im6_msgtype) ||
+	    nla_put_u32(skb, IP6MRA_CREPORT_MIF_ID, msg->im6_mif) ||
+	    nla_put_in6_addr(skb, IP6MRA_CREPORT_SRC_ADDR,
+			     &msg->im6_src) ||
+	    nla_put_in6_addr(skb, IP6MRA_CREPORT_DST_ADDR,
+			     &msg->im6_dst))
+		goto nla_put_failure;
+
+	nla = nla_reserve(skb, IP6MRA_CREPORT_PKT, payloadlen);
+	if (!nla || skb_copy_bits(pkt, sizeof(struct mrt6msg),
+				  nla_data(nla), payloadlen))
+		goto nla_put_failure;
+
+	nlmsg_end(skb, nlh);
+
+	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE_R, NULL, GFP_ATOMIC);
+	return;
+
+nla_put_failure:
+	nlmsg_cancel(skb, nlh);
+errout:
+	kfree_skb(skb);
+	rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
+}
+
+static const struct nla_policy ip6mr_getroute_policy[RTA_MAX + 1] = {
+	[RTA_SRC]		= NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
+	[RTA_DST]		= NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
+	[RTA_TABLE]		= { .type = NLA_U32 },
+};
+
+static int ip6mr_rtm_valid_getroute_req(struct sk_buff *skb,
+					const struct nlmsghdr *nlh,
+					struct nlattr **tb,
+					struct netlink_ext_ack *extack)
+{
+	struct rtmsg *rtm;
+	int err;
+
+	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, ip6mr_getroute_policy,
+			  extack);
+	if (err)
+		return err;
+
+	rtm = nlmsg_data(nlh);
+	if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
+	    (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
+	    rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
+	    rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Invalid values in header for multicast route get request");
+		return -EINVAL;
+	}
+
+	if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
+	    (tb[RTA_DST] && !rtm->rtm_dst_len)) {
+		NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int ip6mr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
+			      struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(in_skb->sk);
+	struct in6_addr src = {}, grp = {};
+	struct nlattr *tb[RTA_MAX + 1];
+	struct mfc6_cache *cache;
+	struct mr_table *mrt;
+	struct sk_buff *skb;
+	u32 tableid;
+	int err;
+
+	err = ip6mr_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
+	if (err < 0)
+		return err;
+
+	if (tb[RTA_SRC])
+		src = nla_get_in6_addr(tb[RTA_SRC]);
+	if (tb[RTA_DST])
+		grp = nla_get_in6_addr(tb[RTA_DST]);
+	tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0;
+
+	mrt = ip6mr_get_table(net, tableid ?: RT_TABLE_DEFAULT);
+	if (!mrt) {
+		NL_SET_ERR_MSG_MOD(extack, "MR table does not exist");
+		return -ENOENT;
+	}
+
+	/* entries are added/deleted only under RTNL */
+	rcu_read_lock();
+	cache = ip6mr_cache_find(mrt, &src, &grp);
+	rcu_read_unlock();
+	if (!cache) {
+		NL_SET_ERR_MSG_MOD(extack, "MR cache entry not found");
+		return -ENOENT;
+	}
+
+	skb = nlmsg_new(mr6_msgsize(false, mrt->maxvif), GFP_KERNEL);
+	if (!skb)
+		return -ENOBUFS;
+
+	err = ip6mr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid,
+				nlh->nlmsg_seq, cache, RTM_NEWROUTE, 0);
+	if (err < 0) {
+		kfree_skb(skb);
+		return err;
+	}
+
+	return rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
+}
+
+static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	const struct nlmsghdr *nlh = cb->nlh;
+	struct fib_dump_filter filter = {};
+	int err;
+
+	if (cb->strict_check) {
+		err = ip_valid_fib_dump_req(sock_net(skb->sk), nlh,
+					    &filter, cb);
+		if (err < 0)
+			return err;
+	}
+
+	if (filter.table_id) {
+		struct mr_table *mrt;
+
+		mrt = ip6mr_get_table(sock_net(skb->sk), filter.table_id);
+		if (!mrt) {
+			if (rtnl_msg_family(cb->nlh) != RTNL_FAMILY_IP6MR)
+				return skb->len;
+
+			NL_SET_ERR_MSG_MOD(cb->extack, "MR table does not exist");
+			return -ENOENT;
+		}
+		err = mr_table_dump(mrt, skb, cb, _ip6mr_fill_mroute,
+				    &mfc_unres_lock, &filter);
+		return skb->len ? : err;
+	}
+
+	return mr_rtm_dumproute(skb, cb, ip6mr_mr_table_iter,
+				_ip6mr_fill_mroute, &mfc_unres_lock, &filter);
+}