Adding upstream version 4.19.249.upstream/4.19.249upstream

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

1 files changed, 3023 insertions, 0 deletions

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
new file mode 100644
index 000000000..3d0484011
--- /dev/null
+++ b/net/ipv6/mcast.c
@@ -0,0 +1,3023 @@
+/*
+ *	Multicast support for IPv6
+ *	Linux INET6 implementation
+ *
+ *	Authors:
+ *	Pedro Roque		<roque@di.fc.ul.pt>
+ *
+ *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+/* Changes:
+ *
+ *	yoshfuji	: fix format of router-alert option
+ *	YOSHIFUJI Hideaki @USAGI:
+ *		Fixed source address for MLD message based on
+ *		<draft-ietf-magma-mld-source-05.txt>.
+ *	YOSHIFUJI Hideaki @USAGI:
+ *		- Ignore Queries for invalid addresses.
+ *		- MLD for link-local addresses.
+ *	David L Stevens <dlstevens@us.ibm.com>:
+ *		- MLDv2 support
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/jiffies.h>
+#include <linux/times.h>
+#include <linux/net.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/route.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/pkt_sched.h>
+#include <net/mld.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/if_inet6.h>
+#include <net/ndisc.h>
+#include <net/addrconf.h>
+#include <net/ip6_route.h>
+#include <net/inet_common.h>
+
+#include <net/ip6_checksum.h>
+
+/* Ensure that we have struct in6_addr aligned on 32bit word. */
+static int __mld2_query_bugs[] __attribute__((__unused__)) = {
+	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
+	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
+	BUILD_BUG_ON_ZERO(offsetof(struct mld2_grec, grec_mca) % 4)
+};
+
+static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
+
+static void igmp6_join_group(struct ifmcaddr6 *ma);
+static void igmp6_leave_group(struct ifmcaddr6 *ma);
+static void igmp6_timer_handler(struct timer_list *t);
+
+static void mld_gq_timer_expire(struct timer_list *t);
+static void mld_ifc_timer_expire(struct timer_list *t);
+static void mld_ifc_event(struct inet6_dev *idev);
+static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
+static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
+static void mld_clear_delrec(struct inet6_dev *idev);
+static bool mld_in_v1_mode(const struct inet6_dev *idev);
+static int sf_setstate(struct ifmcaddr6 *pmc);
+static void sf_markstate(struct ifmcaddr6 *pmc);
+static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
+static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
+			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
+			  int delta);
+static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
+			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
+			  int delta);
+static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
+			    struct inet6_dev *idev);
+static int __ipv6_dev_mc_inc(struct net_device *dev,
+			     const struct in6_addr *addr, unsigned int mode);
+
+#define MLD_QRV_DEFAULT		2
+/* RFC3810, 9.2. Query Interval */
+#define MLD_QI_DEFAULT		(125 * HZ)
+/* RFC3810, 9.3. Query Response Interval */
+#define MLD_QRI_DEFAULT		(10 * HZ)
+
+/* RFC3810, 8.1 Query Version Distinctions */
+#define MLD_V1_QUERY_LEN	24
+#define MLD_V2_QUERY_LEN_MIN	28
+
+#define IPV6_MLD_MAX_MSF	64
+
+int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
+int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
+
+/*
+ *	socket join on multicast group
+ */
+
+#define for_each_pmc_rcu(np, pmc)				\
+	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
+	     pmc != NULL;					\
+	     pmc = rcu_dereference(pmc->next))
+
+static int unsolicited_report_interval(struct inet6_dev *idev)
+{
+	int iv;
+
+	if (mld_in_v1_mode(idev))
+		iv = idev->cnf.mldv1_unsolicited_report_interval;
+	else
+		iv = idev->cnf.mldv2_unsolicited_report_interval;
+
+	return iv > 0 ? iv : 1;
+}
+
+static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
+			       const struct in6_addr *addr, unsigned int mode)
+{
+	struct net_device *dev = NULL;
+	struct ipv6_mc_socklist *mc_lst;
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct net *net = sock_net(sk);
+	int err;
+
+	ASSERT_RTNL();
+
+	if (!ipv6_addr_is_multicast(addr))
+		return -EINVAL;
+
+	rcu_read_lock();
+	for_each_pmc_rcu(np, mc_lst) {
+		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
+		    ipv6_addr_equal(&mc_lst->addr, addr)) {
+			rcu_read_unlock();
+			return -EADDRINUSE;
+		}
+	}
+	rcu_read_unlock();
+
+	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
+
+	if (!mc_lst)
+		return -ENOMEM;
+
+	mc_lst->next = NULL;
+	mc_lst->addr = *addr;
+
+	if (ifindex == 0) {
+		struct rt6_info *rt;
+		rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
+		if (rt) {
+			dev = rt->dst.dev;
+			ip6_rt_put(rt);
+		}
+	} else
+		dev = __dev_get_by_index(net, ifindex);
+
+	if (!dev) {
+		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
+		return -ENODEV;
+	}
+
+	mc_lst->ifindex = dev->ifindex;
+	mc_lst->sfmode = mode;
+	rwlock_init(&mc_lst->sflock);
+	mc_lst->sflist = NULL;
+
+	/*
+	 *	now add/increase the group membership on the device
+	 */
+
+	err = __ipv6_dev_mc_inc(dev, addr, mode);
+
+	if (err) {
+		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
+		return err;
+	}
+
+	mc_lst->next = np->ipv6_mc_list;
+	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
+
+	return 0;
+}
+
+int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
+{
+	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
+}
+EXPORT_SYMBOL(ipv6_sock_mc_join);
+
+int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
+			  const struct in6_addr *addr, unsigned int mode)
+{
+	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
+}
+
+/*
+ *	socket leave on multicast group
+ */
+int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6_mc_socklist *mc_lst;
+	struct ipv6_mc_socklist __rcu **lnk;
+	struct net *net = sock_net(sk);
+
+	ASSERT_RTNL();
+
+	if (!ipv6_addr_is_multicast(addr))
+		return -EINVAL;
+
+	for (lnk = &np->ipv6_mc_list;
+	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
+	      lnk = &mc_lst->next) {
+		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
+		    ipv6_addr_equal(&mc_lst->addr, addr)) {
+			struct net_device *dev;
+
+			*lnk = mc_lst->next;
+
+			dev = __dev_get_by_index(net, mc_lst->ifindex);
+			if (dev) {
+				struct inet6_dev *idev = __in6_dev_get(dev);
+
+				(void) ip6_mc_leave_src(sk, mc_lst, idev);
+				if (idev)
+					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
+			} else
+				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
+
+			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
+			kfree_rcu(mc_lst, rcu);
+			return 0;
+		}
+	}
+
+	return -EADDRNOTAVAIL;
+}
+EXPORT_SYMBOL(ipv6_sock_mc_drop);
+
+/* called with rcu_read_lock() */
+static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
+					     const struct in6_addr *group,
+					     int ifindex)
+{
+	struct net_device *dev = NULL;
+	struct inet6_dev *idev = NULL;
+
+	if (ifindex == 0) {
+		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
+
+		if (rt) {
+			dev = rt->dst.dev;
+			ip6_rt_put(rt);
+		}
+	} else
+		dev = dev_get_by_index_rcu(net, ifindex);
+
+	if (!dev)
+		return NULL;
+	idev = __in6_dev_get(dev);
+	if (!idev)
+		return NULL;
+	read_lock_bh(&idev->lock);
+	if (idev->dead) {
+		read_unlock_bh(&idev->lock);
+		return NULL;
+	}
+	return idev;
+}
+
+void __ipv6_sock_mc_close(struct sock *sk)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6_mc_socklist *mc_lst;
+	struct net *net = sock_net(sk);
+
+	ASSERT_RTNL();
+
+	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
+		struct net_device *dev;
+
+		np->ipv6_mc_list = mc_lst->next;
+
+		dev = __dev_get_by_index(net, mc_lst->ifindex);
+		if (dev) {
+			struct inet6_dev *idev = __in6_dev_get(dev);
+
+			(void) ip6_mc_leave_src(sk, mc_lst, idev);
+			if (idev)
+				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
+		} else
+			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
+
+		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
+		kfree_rcu(mc_lst, rcu);
+	}
+}
+
+void ipv6_sock_mc_close(struct sock *sk)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+
+	if (!rcu_access_pointer(np->ipv6_mc_list))
+		return;
+	rtnl_lock();
+	__ipv6_sock_mc_close(sk);
+	rtnl_unlock();
+}
+
+int ip6_mc_source(int add, int omode, struct sock *sk,
+	struct group_source_req *pgsr)
+{
+	struct in6_addr *source, *group;
+	struct ipv6_mc_socklist *pmc;
+	struct inet6_dev *idev;
+	struct ipv6_pinfo *inet6 = inet6_sk(sk);
+	struct ip6_sf_socklist *psl;
+	struct net *net = sock_net(sk);
+	int i, j, rv;
+	int leavegroup = 0;
+	int pmclocked = 0;
+	int err;
+
+	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
+	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
+
+	if (!ipv6_addr_is_multicast(group))
+		return -EINVAL;
+
+	rcu_read_lock();
+	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
+	if (!idev) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	err = -EADDRNOTAVAIL;
+
+	for_each_pmc_rcu(inet6, pmc) {
+		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
+			continue;
+		if (ipv6_addr_equal(&pmc->addr, group))
+			break;
+	}
+	if (!pmc) {		/* must have a prior join */
+		err = -EINVAL;
+		goto done;
+	}
+	/* if a source filter was set, must be the same mode as before */
+	if (pmc->sflist) {
+		if (pmc->sfmode != omode) {
+			err = -EINVAL;
+			goto done;
+		}
+	} else if (pmc->sfmode != omode) {
+		/* allow mode switches for empty-set filters */
+		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
+		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
+		pmc->sfmode = omode;
+	}
+
+	write_lock(&pmc->sflock);
+	pmclocked = 1;
+
+	psl = pmc->sflist;
+	if (!add) {
+		if (!psl)
+			goto done;	/* err = -EADDRNOTAVAIL */
+		rv = !0;
+		for (i = 0; i < psl->sl_count; i++) {
+			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
+			if (rv == 0)
+				break;
+		}
+		if (rv)		/* source not found */
+			goto done;	/* err = -EADDRNOTAVAIL */
+
+		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
+		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
+			leavegroup = 1;
+			goto done;
+		}
+
+		/* update the interface filter */
+		ip6_mc_del_src(idev, group, omode, 1, source, 1);
+
+		for (j = i+1; j < psl->sl_count; j++)
+			psl->sl_addr[j-1] = psl->sl_addr[j];
+		psl->sl_count--;
+		err = 0;
+		goto done;
+	}
+	/* else, add a new source to the filter */
+
+	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
+		err = -ENOBUFS;
+		goto done;
+	}
+	if (!psl || psl->sl_count == psl->sl_max) {
+		struct ip6_sf_socklist *newpsl;
+		int count = IP6_SFBLOCK;
+
+		if (psl)
+			count += psl->sl_max;
+		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
+		if (!newpsl) {
+			err = -ENOBUFS;
+			goto done;
+		}
+		newpsl->sl_max = count;
+		newpsl->sl_count = count - IP6_SFBLOCK;
+		if (psl) {
+			for (i = 0; i < psl->sl_count; i++)
+				newpsl->sl_addr[i] = psl->sl_addr[i];
+			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
+		}
+		pmc->sflist = psl = newpsl;
+	}
+	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
+	for (i = 0; i < psl->sl_count; i++) {
+		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
+		if (rv == 0) /* There is an error in the address. */
+			goto done;
+	}
+	for (j = psl->sl_count-1; j >= i; j--)
+		psl->sl_addr[j+1] = psl->sl_addr[j];
+	psl->sl_addr[i] = *source;
+	psl->sl_count++;
+	err = 0;
+	/* update the interface list */
+	ip6_mc_add_src(idev, group, omode, 1, source, 1);
+done:
+	if (pmclocked)
+		write_unlock(&pmc->sflock);
+	read_unlock_bh(&idev->lock);
+	rcu_read_unlock();
+	if (leavegroup)
+		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
+	return err;
+}
+
+int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
+{
+	const struct in6_addr *group;
+	struct ipv6_mc_socklist *pmc;
+	struct inet6_dev *idev;
+	struct ipv6_pinfo *inet6 = inet6_sk(sk);
+	struct ip6_sf_socklist *newpsl, *psl;
+	struct net *net = sock_net(sk);
+	int leavegroup = 0;
+	int i, err;
+
+	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
+
+	if (!ipv6_addr_is_multicast(group))
+		return -EINVAL;
+	if (gsf->gf_fmode != MCAST_INCLUDE &&
+	    gsf->gf_fmode != MCAST_EXCLUDE)
+		return -EINVAL;
+
+	rcu_read_lock();
+	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
+
+	if (!idev) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	err = 0;
+
+	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
+		leavegroup = 1;
+		goto done;
+	}
+
+	for_each_pmc_rcu(inet6, pmc) {
+		if (pmc->ifindex != gsf->gf_interface)
+			continue;
+		if (ipv6_addr_equal(&pmc->addr, group))
+			break;
+	}
+	if (!pmc) {		/* must have a prior join */
+		err = -EINVAL;
+		goto done;
+	}
+	if (gsf->gf_numsrc) {
+		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
+							  GFP_ATOMIC);
+		if (!newpsl) {
+			err = -ENOBUFS;
+			goto done;
+		}
+		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
+		for (i = 0; i < newpsl->sl_count; ++i) {
+			struct sockaddr_in6 *psin6;
+
+			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
+			newpsl->sl_addr[i] = psin6->sin6_addr;
+		}
+		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
+			newpsl->sl_count, newpsl->sl_addr, 0);
+		if (err) {
+			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
+			goto done;
+		}
+	} else {
+		newpsl = NULL;
+		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
+	}
+
+	write_lock(&pmc->sflock);
+	psl = pmc->sflist;
+	if (psl) {
+		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
+			psl->sl_count, psl->sl_addr, 0);
+		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
+	} else
+		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
+	pmc->sflist = newpsl;
+	pmc->sfmode = gsf->gf_fmode;
+	write_unlock(&pmc->sflock);
+	err = 0;
+done:
+	read_unlock_bh(&idev->lock);
+	rcu_read_unlock();
+	if (leavegroup)
+		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
+	return err;
+}
+
+int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
+	struct group_filter __user *optval, int __user *optlen)
+{
+	int err, i, count, copycount;
+	const struct in6_addr *group;
+	struct ipv6_mc_socklist *pmc;
+	struct inet6_dev *idev;
+	struct ipv6_pinfo *inet6 = inet6_sk(sk);
+	struct ip6_sf_socklist *psl;
+	struct net *net = sock_net(sk);
+
+	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
+
+	if (!ipv6_addr_is_multicast(group))
+		return -EINVAL;
+
+	rcu_read_lock();
+	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
+
+	if (!idev) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	err = -EADDRNOTAVAIL;
+	/* changes to the ipv6_mc_list require the socket lock and
+	 * rtnl lock. We have the socket lock and rcu read lock,
+	 * so reading the list is safe.
+	 */
+
+	for_each_pmc_rcu(inet6, pmc) {
+		if (pmc->ifindex != gsf->gf_interface)
+			continue;
+		if (ipv6_addr_equal(group, &pmc->addr))
+			break;
+	}
+	if (!pmc)		/* must have a prior join */
+		goto done;
+	gsf->gf_fmode = pmc->sfmode;
+	psl = pmc->sflist;
+	count = psl ? psl->sl_count : 0;
+	read_unlock_bh(&idev->lock);
+	rcu_read_unlock();
+
+	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
+	gsf->gf_numsrc = count;
+	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
+	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
+		return -EFAULT;
+	}
+	/* changes to psl require the socket lock, and a write lock
+	 * on pmc->sflock. We have the socket lock so reading here is safe.
+	 */
+	for (i = 0; i < copycount; i++) {
+		struct sockaddr_in6 *psin6;
+		struct sockaddr_storage ss;
+
+		psin6 = (struct sockaddr_in6 *)&ss;
+		memset(&ss, 0, sizeof(ss));
+		psin6->sin6_family = AF_INET6;
+		psin6->sin6_addr = psl->sl_addr[i];
+		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
+			return -EFAULT;
+	}
+	return 0;
+done:
+	read_unlock_bh(&idev->lock);
+	rcu_read_unlock();
+	return err;
+}
+
+bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
+		    const struct in6_addr *src_addr)
+{
+	struct ipv6_pinfo *np = inet6_sk(sk);
+	struct ipv6_mc_socklist *mc;
+	struct ip6_sf_socklist *psl;
+	bool rv = true;
+
+	rcu_read_lock();
+	for_each_pmc_rcu(np, mc) {
+		if (ipv6_addr_equal(&mc->addr, mc_addr))
+			break;
+	}
+	if (!mc) {
+		rcu_read_unlock();
+		return true;
+	}
+	read_lock(&mc->sflock);
+	psl = mc->sflist;
+	if (!psl) {
+		rv = mc->sfmode == MCAST_EXCLUDE;
+	} else {
+		int i;
+
+		for (i = 0; i < psl->sl_count; i++) {
+			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
+				break;
+		}
+		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
+			rv = false;
+		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
+			rv = false;
+	}
+	read_unlock(&mc->sflock);
+	rcu_read_unlock();
+
+	return rv;
+}
+
+static void igmp6_group_added(struct ifmcaddr6 *mc)
+{
+	struct net_device *dev = mc->idev->dev;
+	char buf[MAX_ADDR_LEN];
+
+	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
+	    IPV6_ADDR_SCOPE_LINKLOCAL)
+		return;
+
+	spin_lock_bh(&mc->mca_lock);
+	if (!(mc->mca_flags&MAF_LOADED)) {
+		mc->mca_flags |= MAF_LOADED;
+		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
+			dev_mc_add(dev, buf);
+	}
+	spin_unlock_bh(&mc->mca_lock);
+
+	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
+		return;
+
+	if (mld_in_v1_mode(mc->idev)) {
+		igmp6_join_group(mc);
+		return;
+	}
+	/* else v2 */
+
+	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
+	 * should not send filter-mode change record as the mode
+	 * should be from IN() to IN(A).
+	 */
+	if (mc->mca_sfmode == MCAST_EXCLUDE)
+		mc->mca_crcount = mc->idev->mc_qrv;
+
+	mld_ifc_event(mc->idev);
+}
+
+static void igmp6_group_dropped(struct ifmcaddr6 *mc)
+{
+	struct net_device *dev = mc->idev->dev;
+	char buf[MAX_ADDR_LEN];
+
+	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
+	    IPV6_ADDR_SCOPE_LINKLOCAL)
+		return;
+
+	spin_lock_bh(&mc->mca_lock);
+	if (mc->mca_flags&MAF_LOADED) {
+		mc->mca_flags &= ~MAF_LOADED;
+		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
+			dev_mc_del(dev, buf);
+	}
+
+	spin_unlock_bh(&mc->mca_lock);
+	if (mc->mca_flags & MAF_NOREPORT)
+		return;
+
+	if (!mc->idev->dead)
+		igmp6_leave_group(mc);
+
+	spin_lock_bh(&mc->mca_lock);
+	if (del_timer(&mc->mca_timer))
+		refcount_dec(&mc->mca_refcnt);
+	spin_unlock_bh(&mc->mca_lock);
+}
+
+/*
+ * deleted ifmcaddr6 manipulation
+ */
+static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
+{
+	struct ifmcaddr6 *pmc;
+
+	/* this is an "ifmcaddr6" for convenience; only the fields below
+	 * are actually used. In particular, the refcnt and users are not
+	 * used for management of the delete list. Using the same structure
+	 * for deleted items allows change reports to use common code with
+	 * non-deleted or query-response MCA's.
+	 */
+	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
+	if (!pmc)
+		return;
+
+	spin_lock_bh(&im->mca_lock);
+	spin_lock_init(&pmc->mca_lock);
+	pmc->idev = im->idev;
+	in6_dev_hold(idev);
+	pmc->mca_addr = im->mca_addr;
+	pmc->mca_crcount = idev->mc_qrv;
+	pmc->mca_sfmode = im->mca_sfmode;
+	if (pmc->mca_sfmode == MCAST_INCLUDE) {
+		struct ip6_sf_list *psf;
+
+		pmc->mca_tomb = im->mca_tomb;
+		pmc->mca_sources = im->mca_sources;
+		im->mca_tomb = im->mca_sources = NULL;
+		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
+			psf->sf_crcount = pmc->mca_crcount;
+	}
+	spin_unlock_bh(&im->mca_lock);
+
+	spin_lock_bh(&idev->mc_lock);
+	pmc->next = idev->mc_tomb;
+	idev->mc_tomb = pmc;
+	spin_unlock_bh(&idev->mc_lock);
+}
+
+static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
+{
+	struct ifmcaddr6 *pmc, *pmc_prev;
+	struct ip6_sf_list *psf;
+	struct in6_addr *pmca = &im->mca_addr;
+
+	spin_lock_bh(&idev->mc_lock);
+	pmc_prev = NULL;
+	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
+		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
+			break;
+		pmc_prev = pmc;
+	}
+	if (pmc) {
+		if (pmc_prev)
+			pmc_prev->next = pmc->next;
+		else
+			idev->mc_tomb = pmc->next;
+	}
+	spin_unlock_bh(&idev->mc_lock);
+
+	spin_lock_bh(&im->mca_lock);
+	if (pmc) {
+		im->idev = pmc->idev;
+		if (im->mca_sfmode == MCAST_INCLUDE) {
+			swap(im->mca_tomb, pmc->mca_tomb);
+			swap(im->mca_sources, pmc->mca_sources);
+			for (psf = im->mca_sources; psf; psf = psf->sf_next)
+				psf->sf_crcount = idev->mc_qrv;
+		} else {
+			im->mca_crcount = idev->mc_qrv;
+		}
+		in6_dev_put(pmc->idev);
+		ip6_mc_clear_src(pmc);
+		kfree(pmc);
+	}
+	spin_unlock_bh(&im->mca_lock);
+}
+
+static void mld_clear_delrec(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *pmc, *nextpmc;
+
+	spin_lock_bh(&idev->mc_lock);
+	pmc = idev->mc_tomb;
+	idev->mc_tomb = NULL;
+	spin_unlock_bh(&idev->mc_lock);
+
+	for (; pmc; pmc = nextpmc) {
+		nextpmc = pmc->next;
+		ip6_mc_clear_src(pmc);
+		in6_dev_put(pmc->idev);
+		kfree(pmc);
+	}
+
+	/* clear dead sources, too */
+	read_lock_bh(&idev->lock);
+	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+		struct ip6_sf_list *psf, *psf_next;
+
+		spin_lock_bh(&pmc->mca_lock);
+		psf = pmc->mca_tomb;
+		pmc->mca_tomb = NULL;
+		spin_unlock_bh(&pmc->mca_lock);
+		for (; psf; psf = psf_next) {
+			psf_next = psf->sf_next;
+			kfree(psf);
+		}
+	}
+	read_unlock_bh(&idev->lock);
+}
+
+static void mca_get(struct ifmcaddr6 *mc)
+{
+	refcount_inc(&mc->mca_refcnt);
+}
+
+static void ma_put(struct ifmcaddr6 *mc)
+{
+	if (refcount_dec_and_test(&mc->mca_refcnt)) {
+		in6_dev_put(mc->idev);
+		kfree(mc);
+	}
+}
+
+static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
+				   const struct in6_addr *addr,
+				   unsigned int mode)
+{
+	struct ifmcaddr6 *mc;
+
+	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
+	if (!mc)
+		return NULL;
+
+	timer_setup(&mc->mca_timer, igmp6_timer_handler, 0);
+
+	mc->mca_addr = *addr;
+	mc->idev = idev; /* reference taken by caller */
+	mc->mca_users = 1;
+	/* mca_stamp should be updated upon changes */
+	mc->mca_cstamp = mc->mca_tstamp = jiffies;
+	refcount_set(&mc->mca_refcnt, 1);
+	spin_lock_init(&mc->mca_lock);
+
+	mc->mca_sfmode = mode;
+	mc->mca_sfcount[mode] = 1;
+
+	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
+	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
+		mc->mca_flags |= MAF_NOREPORT;
+
+	return mc;
+}
+
+/*
+ *	device multicast group inc (add if not found)
+ */
+static int __ipv6_dev_mc_inc(struct net_device *dev,
+			     const struct in6_addr *addr, unsigned int mode)
+{
+	struct ifmcaddr6 *mc;
+	struct inet6_dev *idev;
+
+	ASSERT_RTNL();
+
+	/* we need to take a reference on idev */
+	idev = in6_dev_get(dev);
+
+	if (!idev)
+		return -EINVAL;
+
+	write_lock_bh(&idev->lock);
+	if (idev->dead) {
+		write_unlock_bh(&idev->lock);
+		in6_dev_put(idev);
+		return -ENODEV;
+	}
+
+	for (mc = idev->mc_list; mc; mc = mc->next) {
+		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
+			mc->mca_users++;
+			write_unlock_bh(&idev->lock);
+			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
+			in6_dev_put(idev);
+			return 0;
+		}
+	}
+
+	mc = mca_alloc(idev, addr, mode);
+	if (!mc) {
+		write_unlock_bh(&idev->lock);
+		in6_dev_put(idev);
+		return -ENOMEM;
+	}
+
+	mc->next = idev->mc_list;
+	idev->mc_list = mc;
+
+	/* Hold this for the code below before we unlock,
+	 * it is already exposed via idev->mc_list.
+	 */
+	mca_get(mc);
+	write_unlock_bh(&idev->lock);
+
+	mld_del_delrec(idev, mc);
+	igmp6_group_added(mc);
+	ma_put(mc);
+	return 0;
+}
+
+int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
+{
+	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
+}
+
+/*
+ *	device multicast group del
+ */
+int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
+{
+	struct ifmcaddr6 *ma, **map;
+
+	ASSERT_RTNL();
+
+	write_lock_bh(&idev->lock);
+	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
+		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
+			if (--ma->mca_users == 0) {
+				*map = ma->next;
+				write_unlock_bh(&idev->lock);
+
+				igmp6_group_dropped(ma);
+				ip6_mc_clear_src(ma);
+
+				ma_put(ma);
+				return 0;
+			}
+			write_unlock_bh(&idev->lock);
+			return 0;
+		}
+	}
+	write_unlock_bh(&idev->lock);
+
+	return -ENOENT;
+}
+
+int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
+{
+	struct inet6_dev *idev;
+	int err;
+
+	ASSERT_RTNL();
+
+	idev = __in6_dev_get(dev);
+	if (!idev)
+		err = -ENODEV;
+	else
+		err = __ipv6_dev_mc_dec(idev, addr);
+
+	return err;
+}
+
+/*
+ *	check if the interface/address pair is valid
+ */
+bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
+			 const struct in6_addr *src_addr)
+{
+	struct inet6_dev *idev;
+	struct ifmcaddr6 *mc;
+	bool rv = false;
+
+	rcu_read_lock();
+	idev = __in6_dev_get(dev);
+	if (idev) {
+		read_lock_bh(&idev->lock);
+		for (mc = idev->mc_list; mc; mc = mc->next) {
+			if (ipv6_addr_equal(&mc->mca_addr, group))
+				break;
+		}
+		if (mc) {
+			if (src_addr && !ipv6_addr_any(src_addr)) {
+				struct ip6_sf_list *psf;
+
+				spin_lock_bh(&mc->mca_lock);
+				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
+					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
+						break;
+				}
+				if (psf)
+					rv = psf->sf_count[MCAST_INCLUDE] ||
+						psf->sf_count[MCAST_EXCLUDE] !=
+						mc->mca_sfcount[MCAST_EXCLUDE];
+				else
+					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
+				spin_unlock_bh(&mc->mca_lock);
+			} else
+				rv = true; /* don't filter unspecified source */
+		}
+		read_unlock_bh(&idev->lock);
+	}
+	rcu_read_unlock();
+	return rv;
+}
+
+static void mld_gq_start_timer(struct inet6_dev *idev)
+{
+	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
+
+	idev->mc_gq_running = 1;
+	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
+		in6_dev_hold(idev);
+}
+
+static void mld_gq_stop_timer(struct inet6_dev *idev)
+{
+	idev->mc_gq_running = 0;
+	if (del_timer(&idev->mc_gq_timer))
+		__in6_dev_put(idev);
+}
+
+static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
+{
+	unsigned long tv = prandom_u32() % delay;
+
+	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
+		in6_dev_hold(idev);
+}
+
+static void mld_ifc_stop_timer(struct inet6_dev *idev)
+{
+	idev->mc_ifc_count = 0;
+	if (del_timer(&idev->mc_ifc_timer))
+		__in6_dev_put(idev);
+}
+
+static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
+{
+	unsigned long tv = prandom_u32() % delay;
+
+	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
+		in6_dev_hold(idev);
+}
+
+static void mld_dad_stop_timer(struct inet6_dev *idev)
+{
+	if (del_timer(&idev->mc_dad_timer))
+		__in6_dev_put(idev);
+}
+
+/*
+ *	IGMP handling (alias multicast ICMPv6 messages)
+ */
+
+static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
+{
+	unsigned long delay = resptime;
+
+	/* Do not start timer for these addresses */
+	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
+	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
+		return;
+
+	if (del_timer(&ma->mca_timer)) {
+		refcount_dec(&ma->mca_refcnt);
+		delay = ma->mca_timer.expires - jiffies;
+	}
+
+	if (delay >= resptime)
+		delay = prandom_u32() % resptime;
+
+	ma->mca_timer.expires = jiffies + delay;
+	if (!mod_timer(&ma->mca_timer, jiffies + delay))
+		refcount_inc(&ma->mca_refcnt);
+	ma->mca_flags |= MAF_TIMER_RUNNING;
+}
+
+/* mark EXCLUDE-mode sources */
+static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
+			     const struct in6_addr *srcs)
+{
+	struct ip6_sf_list *psf;
+	int i, scount;
+
+	scount = 0;
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (scount == nsrcs)
+			break;
+		for (i = 0; i < nsrcs; i++) {
+			/* skip inactive filters */
+			if (psf->sf_count[MCAST_INCLUDE] ||
+			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
+			    psf->sf_count[MCAST_EXCLUDE])
+				break;
+			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
+				scount++;
+				break;
+			}
+		}
+	}
+	pmc->mca_flags &= ~MAF_GSQUERY;
+	if (scount == nsrcs)	/* all sources excluded */
+		return false;
+	return true;
+}
+
+static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
+			    const struct in6_addr *srcs)
+{
+	struct ip6_sf_list *psf;
+	int i, scount;
+
+	if (pmc->mca_sfmode == MCAST_EXCLUDE)
+		return mld_xmarksources(pmc, nsrcs, srcs);
+
+	/* mark INCLUDE-mode sources */
+
+	scount = 0;
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (scount == nsrcs)
+			break;
+		for (i = 0; i < nsrcs; i++) {
+			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
+				psf->sf_gsresp = 1;
+				scount++;
+				break;
+			}
+		}
+	}
+	if (!scount) {
+		pmc->mca_flags &= ~MAF_GSQUERY;
+		return false;
+	}
+	pmc->mca_flags |= MAF_GSQUERY;
+	return true;
+}
+
+static int mld_force_mld_version(const struct inet6_dev *idev)
+{
+	/* Normally, both are 0 here. If enforcement to a particular is
+	 * being used, individual device enforcement will have a lower
+	 * precedence over 'all' device (.../conf/all/force_mld_version).
+	 */
+
+	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
+		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
+	else
+		return idev->cnf.force_mld_version;
+}
+
+static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
+{
+	return mld_force_mld_version(idev) == 2;
+}
+
+static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
+{
+	return mld_force_mld_version(idev) == 1;
+}
+
+static bool mld_in_v1_mode(const struct inet6_dev *idev)
+{
+	if (mld_in_v2_mode_only(idev))
+		return false;
+	if (mld_in_v1_mode_only(idev))
+		return true;
+	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
+		return true;
+
+	return false;
+}
+
+static void mld_set_v1_mode(struct inet6_dev *idev)
+{
+	/* RFC3810, relevant sections:
+	 *  - 9.1. Robustness Variable
+	 *  - 9.2. Query Interval
+	 *  - 9.3. Query Response Interval
+	 *  - 9.12. Older Version Querier Present Timeout
+	 */
+	unsigned long switchback;
+
+	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
+
+	idev->mc_v1_seen = jiffies + switchback;
+}
+
+static void mld_update_qrv(struct inet6_dev *idev,
+			   const struct mld2_query *mlh2)
+{
+	/* RFC3810, relevant sections:
+	 *  - 5.1.8. QRV (Querier's Robustness Variable)
+	 *  - 9.1. Robustness Variable
+	 */
+
+	/* The value of the Robustness Variable MUST NOT be zero,
+	 * and SHOULD NOT be one. Catch this here if we ever run
+	 * into such a case in future.
+	 */
+	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
+	WARN_ON(idev->mc_qrv == 0);
+
+	if (mlh2->mld2q_qrv > 0)
+		idev->mc_qrv = mlh2->mld2q_qrv;
+
+	if (unlikely(idev->mc_qrv < min_qrv)) {
+		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
+				     idev->mc_qrv, min_qrv);
+		idev->mc_qrv = min_qrv;
+	}
+}
+
+static void mld_update_qi(struct inet6_dev *idev,
+			  const struct mld2_query *mlh2)
+{
+	/* RFC3810, relevant sections:
+	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
+	 *  - 9.2. Query Interval
+	 *  - 9.12. Older Version Querier Present Timeout
+	 *    (the [Query Interval] in the last Query received)
+	 */
+	unsigned long mc_qqi;
+
+	if (mlh2->mld2q_qqic < 128) {
+		mc_qqi = mlh2->mld2q_qqic;
+	} else {
+		unsigned long mc_man, mc_exp;
+
+		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
+		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
+
+		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
+	}
+
+	idev->mc_qi = mc_qqi * HZ;
+}
+
+static void mld_update_qri(struct inet6_dev *idev,
+			   const struct mld2_query *mlh2)
+{
+	/* RFC3810, relevant sections:
+	 *  - 5.1.3. Maximum Response Code
+	 *  - 9.3. Query Response Interval
+	 */
+	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
+}
+
+static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
+			  unsigned long *max_delay, bool v1_query)
+{
+	unsigned long mldv1_md;
+
+	/* Ignore v1 queries */
+	if (mld_in_v2_mode_only(idev))
+		return -EINVAL;
+
+	mldv1_md = ntohs(mld->mld_maxdelay);
+
+	/* When in MLDv1 fallback and a MLDv2 router start-up being
+	 * unaware of current MLDv1 operation, the MRC == MRD mapping
+	 * only works when the exponential algorithm is not being
+	 * used (as MLDv1 is unaware of such things).
+	 *
+	 * According to the RFC author, the MLDv2 implementations
+	 * he's aware of all use a MRC < 32768 on start up queries.
+	 *
+	 * Thus, should we *ever* encounter something else larger
+	 * than that, just assume the maximum possible within our
+	 * reach.
+	 */
+	if (!v1_query)
+		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
+
+	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
+
+	/* MLDv1 router present: we need to go into v1 mode *only*
+	 * when an MLDv1 query is received as per section 9.12. of
+	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
+	 * queries MUST be of exactly 24 octets.
+	 */
+	if (v1_query)
+		mld_set_v1_mode(idev);
+
+	/* cancel MLDv2 report timer */
+	mld_gq_stop_timer(idev);
+	/* cancel the interface change timer */
+	mld_ifc_stop_timer(idev);
+	/* clear deleted report items */
+	mld_clear_delrec(idev);
+
+	return 0;
+}
+
+static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
+			  unsigned long *max_delay)
+{
+	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
+
+	mld_update_qrv(idev, mld);
+	mld_update_qi(idev, mld);
+	mld_update_qri(idev, mld);
+
+	idev->mc_maxdelay = *max_delay;
+
+	return 0;
+}
+
+/* called with rcu_read_lock() */
+int igmp6_event_query(struct sk_buff *skb)
+{
+	struct mld2_query *mlh2 = NULL;
+	struct ifmcaddr6 *ma;
+	const struct in6_addr *group;
+	unsigned long max_delay;
+	struct inet6_dev *idev;
+	struct mld_msg *mld;
+	int group_type;
+	int mark = 0;
+	int len, err;
+
+	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
+		return -EINVAL;
+
+	/* compute payload length excluding extension headers */
+	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
+	len -= skb_network_header_len(skb);
+
+	/* RFC3810 6.2
+	 * Upon reception of an MLD message that contains a Query, the node
+	 * checks if the source address of the message is a valid link-local
+	 * address, if the Hop Limit is set to 1, and if the Router Alert
+	 * option is present in the Hop-By-Hop Options header of the IPv6
+	 * packet.  If any of these checks fails, the packet is dropped.
+	 */
+	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
+	    ipv6_hdr(skb)->hop_limit != 1 ||
+	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
+	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
+		return -EINVAL;
+
+	idev = __in6_dev_get(skb->dev);
+	if (!idev)
+		return 0;
+
+	mld = (struct mld_msg *)icmp6_hdr(skb);
+	group = &mld->mld_mca;
+	group_type = ipv6_addr_type(group);
+
+	if (group_type != IPV6_ADDR_ANY &&
+	    !(group_type&IPV6_ADDR_MULTICAST))
+		return -EINVAL;
+
+	if (len < MLD_V1_QUERY_LEN) {
+		return -EINVAL;
+	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
+		err = mld_process_v1(idev, mld, &max_delay,
+				     len == MLD_V1_QUERY_LEN);
+		if (err < 0)
+			return err;
+	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
+		int srcs_offset = sizeof(struct mld2_query) -
+				  sizeof(struct icmp6hdr);
+
+		if (!pskb_may_pull(skb, srcs_offset))
+			return -EINVAL;
+
+		mlh2 = (struct mld2_query *)skb_transport_header(skb);
+
+		err = mld_process_v2(idev, mlh2, &max_delay);
+		if (err < 0)
+			return err;
+
+		if (group_type == IPV6_ADDR_ANY) { /* general query */
+			if (mlh2->mld2q_nsrcs)
+				return -EINVAL; /* no sources allowed */
+
+			mld_gq_start_timer(idev);
+			return 0;
+		}
+		/* mark sources to include, if group & source-specific */
+		if (mlh2->mld2q_nsrcs != 0) {
+			if (!pskb_may_pull(skb, srcs_offset +
+			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
+				return -EINVAL;
+
+			mlh2 = (struct mld2_query *)skb_transport_header(skb);
+			mark = 1;
+		}
+	} else {
+		return -EINVAL;
+	}
+
+	read_lock_bh(&idev->lock);
+	if (group_type == IPV6_ADDR_ANY) {
+		for (ma = idev->mc_list; ma; ma = ma->next) {
+			spin_lock_bh(&ma->mca_lock);
+			igmp6_group_queried(ma, max_delay);
+			spin_unlock_bh(&ma->mca_lock);
+		}
+	} else {
+		for (ma = idev->mc_list; ma; ma = ma->next) {
+			if (!ipv6_addr_equal(group, &ma->mca_addr))
+				continue;
+			spin_lock_bh(&ma->mca_lock);
+			if (ma->mca_flags & MAF_TIMER_RUNNING) {
+				/* gsquery <- gsquery && mark */
+				if (!mark)
+					ma->mca_flags &= ~MAF_GSQUERY;
+			} else {
+				/* gsquery <- mark */
+				if (mark)
+					ma->mca_flags |= MAF_GSQUERY;
+				else
+					ma->mca_flags &= ~MAF_GSQUERY;
+			}
+			if (!(ma->mca_flags & MAF_GSQUERY) ||
+			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
+				igmp6_group_queried(ma, max_delay);
+			spin_unlock_bh(&ma->mca_lock);
+			break;
+		}
+	}
+	read_unlock_bh(&idev->lock);
+
+	return 0;
+}
+
+/* called with rcu_read_lock() */
+int igmp6_event_report(struct sk_buff *skb)
+{
+	struct ifmcaddr6 *ma;
+	struct inet6_dev *idev;
+	struct mld_msg *mld;
+	int addr_type;
+
+	/* Our own report looped back. Ignore it. */
+	if (skb->pkt_type == PACKET_LOOPBACK)
+		return 0;
+
+	/* send our report if the MC router may not have heard this report */
+	if (skb->pkt_type != PACKET_MULTICAST &&
+	    skb->pkt_type != PACKET_BROADCAST)
+		return 0;
+
+	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
+		return -EINVAL;
+
+	mld = (struct mld_msg *)icmp6_hdr(skb);
+
+	/* Drop reports with not link local source */
+	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
+	if (addr_type != IPV6_ADDR_ANY &&
+	    !(addr_type&IPV6_ADDR_LINKLOCAL))
+		return -EINVAL;
+
+	idev = __in6_dev_get(skb->dev);
+	if (!idev)
+		return -ENODEV;
+
+	/*
+	 *	Cancel the timer for this group
+	 */
+
+	read_lock_bh(&idev->lock);
+	for (ma = idev->mc_list; ma; ma = ma->next) {
+		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
+			spin_lock(&ma->mca_lock);
+			if (del_timer(&ma->mca_timer))
+				refcount_dec(&ma->mca_refcnt);
+			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
+			spin_unlock(&ma->mca_lock);
+			break;
+		}
+	}
+	read_unlock_bh(&idev->lock);
+	return 0;
+}
+
+static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
+		  int gdeleted, int sdeleted)
+{
+	switch (type) {
+	case MLD2_MODE_IS_INCLUDE:
+	case MLD2_MODE_IS_EXCLUDE:
+		if (gdeleted || sdeleted)
+			return false;
+		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
+			if (pmc->mca_sfmode == MCAST_INCLUDE)
+				return true;
+			/* don't include if this source is excluded
+			 * in all filters
+			 */
+			if (psf->sf_count[MCAST_INCLUDE])
+				return type == MLD2_MODE_IS_INCLUDE;
+			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
+				psf->sf_count[MCAST_EXCLUDE];
+		}
+		return false;
+	case MLD2_CHANGE_TO_INCLUDE:
+		if (gdeleted || sdeleted)
+			return false;
+		return psf->sf_count[MCAST_INCLUDE] != 0;
+	case MLD2_CHANGE_TO_EXCLUDE:
+		if (gdeleted || sdeleted)
+			return false;
+		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
+		    psf->sf_count[MCAST_INCLUDE])
+			return false;
+		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
+			psf->sf_count[MCAST_EXCLUDE];
+	case MLD2_ALLOW_NEW_SOURCES:
+		if (gdeleted || !psf->sf_crcount)
+			return false;
+		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
+	case MLD2_BLOCK_OLD_SOURCES:
+		if (pmc->mca_sfmode == MCAST_INCLUDE)
+			return gdeleted || (psf->sf_crcount && sdeleted);
+		return psf->sf_crcount && !gdeleted && !sdeleted;
+	}
+	return false;
+}
+
+static int
+mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
+{
+	struct ip6_sf_list *psf;
+	int scount = 0;
+
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
+			continue;
+		scount++;
+	}
+	return scount;
+}
+
+static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
+		       struct net_device *dev,
+		       const struct in6_addr *saddr,
+		       const struct in6_addr *daddr,
+		       int proto, int len)
+{
+	struct ipv6hdr *hdr;
+
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->dev = dev;
+
+	skb_reset_network_header(skb);
+	skb_put(skb, sizeof(struct ipv6hdr));
+	hdr = ipv6_hdr(skb);
+
+	ip6_flow_hdr(hdr, 0, 0);
+
+	hdr->payload_len = htons(len);
+	hdr->nexthdr = proto;
+	hdr->hop_limit = inet6_sk(sk)->hop_limit;
+
+	hdr->saddr = *saddr;
+	hdr->daddr = *daddr;
+}
+
+static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
+{
+	struct net_device *dev = idev->dev;
+	struct net *net = dev_net(dev);
+	struct sock *sk = net->ipv6.igmp_sk;
+	struct sk_buff *skb;
+	struct mld2_report *pmr;
+	struct in6_addr addr_buf;
+	const struct in6_addr *saddr;
+	int hlen = LL_RESERVED_SPACE(dev);
+	int tlen = dev->needed_tailroom;
+	unsigned int size = mtu + hlen + tlen;
+	int err;
+	u8 ra[8] = { IPPROTO_ICMPV6, 0,
+		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
+		     IPV6_TLV_PADN, 0 };
+
+	/* we assume size > sizeof(ra) here */
+	skb = sock_alloc_send_skb(sk, size, 1, &err);
+	if (!skb)
+		return NULL;
+
+	skb->priority = TC_PRIO_CONTROL;
+	skb_reserve(skb, hlen);
+	skb_tailroom_reserve(skb, mtu, tlen);
+
+	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
+		/* <draft-ietf-magma-mld-source-05.txt>:
+		 * use unspecified address as the source address
+		 * when a valid link-local address is not available.
+		 */
+		saddr = &in6addr_any;
+	} else
+		saddr = &addr_buf;
+
+	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
+
+	skb_put_data(skb, ra, sizeof(ra));
+
+	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
+	skb_put(skb, sizeof(*pmr));
+	pmr = (struct mld2_report *)skb_transport_header(skb);
+	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
+	pmr->mld2r_resv1 = 0;
+	pmr->mld2r_cksum = 0;
+	pmr->mld2r_resv2 = 0;
+	pmr->mld2r_ngrec = 0;
+	return skb;
+}
+
+static void mld_sendpack(struct sk_buff *skb)
+{
+	struct ipv6hdr *pip6 = ipv6_hdr(skb);
+	struct mld2_report *pmr =
+			      (struct mld2_report *)skb_transport_header(skb);
+	int payload_len, mldlen;
+	struct inet6_dev *idev;
+	struct net *net = dev_net(skb->dev);
+	int err;
+	struct flowi6 fl6;
+	struct dst_entry *dst;
+
+	rcu_read_lock();
+	idev = __in6_dev_get(skb->dev);
+	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
+
+	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
+		sizeof(*pip6);
+	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
+	pip6->payload_len = htons(payload_len);
+
+	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
+					   IPPROTO_ICMPV6,
+					   csum_partial(skb_transport_header(skb),
+							mldlen, 0));
+
+	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
+			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
+			 skb->dev->ifindex);
+	dst = icmp6_dst_alloc(skb->dev, &fl6);
+
+	err = 0;
+	if (IS_ERR(dst)) {
+		err = PTR_ERR(dst);
+		dst = NULL;
+	}
+	skb_dst_set(skb, dst);
+	if (err)
+		goto err_out;
+
+	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
+		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
+		      dst_output);
+out:
+	if (!err) {
+		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
+		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
+	} else {
+		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
+	}
+
+	rcu_read_unlock();
+	return;
+
+err_out:
+	kfree_skb(skb);
+	goto out;
+}
+
+static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
+{
+	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
+}
+
+static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
+	int type, struct mld2_grec **ppgr, unsigned int mtu)
+{
+	struct mld2_report *pmr;
+	struct mld2_grec *pgr;
+
+	if (!skb) {
+		skb = mld_newpack(pmc->idev, mtu);
+		if (!skb)
+			return NULL;
+	}
+	pgr = skb_put(skb, sizeof(struct mld2_grec));
+	pgr->grec_type = type;
+	pgr->grec_auxwords = 0;
+	pgr->grec_nsrcs = 0;
+	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
+	pmr = (struct mld2_report *)skb_transport_header(skb);
+	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
+	*ppgr = pgr;
+	return skb;
+}
+
+#define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
+
+static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
+	int type, int gdeleted, int sdeleted, int crsend)
+{
+	struct inet6_dev *idev = pmc->idev;
+	struct net_device *dev = idev->dev;
+	struct mld2_report *pmr;
+	struct mld2_grec *pgr = NULL;
+	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
+	int scount, stotal, first, isquery, truncate;
+	unsigned int mtu;
+
+	if (pmc->mca_flags & MAF_NOREPORT)
+		return skb;
+
+	mtu = READ_ONCE(dev->mtu);
+	if (mtu < IPV6_MIN_MTU)
+		return skb;
+
+	isquery = type == MLD2_MODE_IS_INCLUDE ||
+		  type == MLD2_MODE_IS_EXCLUDE;
+	truncate = type == MLD2_MODE_IS_EXCLUDE ||
+		    type == MLD2_CHANGE_TO_EXCLUDE;
+
+	stotal = scount = 0;
+
+	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
+
+	if (!*psf_list)
+		goto empty_source;
+
+	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
+
+	/* EX and TO_EX get a fresh packet, if needed */
+	if (truncate) {
+		if (pmr && pmr->mld2r_ngrec &&
+		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
+			if (skb)
+				mld_sendpack(skb);
+			skb = mld_newpack(idev, mtu);
+		}
+	}
+	first = 1;
+	psf_prev = NULL;
+	for (psf = *psf_list; psf; psf = psf_next) {
+		struct in6_addr *psrc;
+
+		psf_next = psf->sf_next;
+
+		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
+			psf_prev = psf;
+			continue;
+		}
+
+		/* Based on RFC3810 6.1. Should not send source-list change
+		 * records when there is a filter mode change.
+		 */
+		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
+		     (!gdeleted && pmc->mca_crcount)) &&
+		    (type == MLD2_ALLOW_NEW_SOURCES ||
+		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
+			goto decrease_sf_crcount;
+
+		/* clear marks on query responses */
+		if (isquery)
+			psf->sf_gsresp = 0;
+
+		if (AVAILABLE(skb) < sizeof(*psrc) +
+		    first*sizeof(struct mld2_grec)) {
+			if (truncate && !first)
+				break;	 /* truncate these */
+			if (pgr)
+				pgr->grec_nsrcs = htons(scount);
+			if (skb)
+				mld_sendpack(skb);
+			skb = mld_newpack(idev, mtu);
+			first = 1;
+			scount = 0;
+		}
+		if (first) {
+			skb = add_grhead(skb, pmc, type, &pgr, mtu);
+			first = 0;
+		}
+		if (!skb)
+			return NULL;
+		psrc = skb_put(skb, sizeof(*psrc));
+		*psrc = psf->sf_addr;
+		scount++; stotal++;
+		if ((type == MLD2_ALLOW_NEW_SOURCES ||
+		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
+decrease_sf_crcount:
+			psf->sf_crcount--;
+			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
+				if (psf_prev)
+					psf_prev->sf_next = psf->sf_next;
+				else
+					*psf_list = psf->sf_next;
+				kfree(psf);
+				continue;
+			}
+		}
+		psf_prev = psf;
+	}
+
+empty_source:
+	if (!stotal) {
+		if (type == MLD2_ALLOW_NEW_SOURCES ||
+		    type == MLD2_BLOCK_OLD_SOURCES)
+			return skb;
+		if (pmc->mca_crcount || isquery || crsend) {
+			/* make sure we have room for group header */
+			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
+				mld_sendpack(skb);
+				skb = NULL; /* add_grhead will get a new one */
+			}
+			skb = add_grhead(skb, pmc, type, &pgr, mtu);
+		}
+	}
+	if (pgr)
+		pgr->grec_nsrcs = htons(scount);
+
+	if (isquery)
+		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
+	return skb;
+}
+
+static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
+{
+	struct sk_buff *skb = NULL;
+	int type;
+
+	read_lock_bh(&idev->lock);
+	if (!pmc) {
+		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+			if (pmc->mca_flags & MAF_NOREPORT)
+				continue;
+			spin_lock_bh(&pmc->mca_lock);
+			if (pmc->mca_sfcount[MCAST_EXCLUDE])
+				type = MLD2_MODE_IS_EXCLUDE;
+			else
+				type = MLD2_MODE_IS_INCLUDE;
+			skb = add_grec(skb, pmc, type, 0, 0, 0);
+			spin_unlock_bh(&pmc->mca_lock);
+		}
+	} else {
+		spin_lock_bh(&pmc->mca_lock);
+		if (pmc->mca_sfcount[MCAST_EXCLUDE])
+			type = MLD2_MODE_IS_EXCLUDE;
+		else
+			type = MLD2_MODE_IS_INCLUDE;
+		skb = add_grec(skb, pmc, type, 0, 0, 0);
+		spin_unlock_bh(&pmc->mca_lock);
+	}
+	read_unlock_bh(&idev->lock);
+	if (skb)
+		mld_sendpack(skb);
+}
+
+/*
+ * remove zero-count source records from a source filter list
+ */
+static void mld_clear_zeros(struct ip6_sf_list **ppsf)
+{
+	struct ip6_sf_list *psf_prev, *psf_next, *psf;
+
+	psf_prev = NULL;
+	for (psf = *ppsf; psf; psf = psf_next) {
+		psf_next = psf->sf_next;
+		if (psf->sf_crcount == 0) {
+			if (psf_prev)
+				psf_prev->sf_next = psf->sf_next;
+			else
+				*ppsf = psf->sf_next;
+			kfree(psf);
+		} else
+			psf_prev = psf;
+	}
+}
+
+static void mld_send_cr(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
+	struct sk_buff *skb = NULL;
+	int type, dtype;
+
+	read_lock_bh(&idev->lock);
+	spin_lock(&idev->mc_lock);
+
+	/* deleted MCA's */
+	pmc_prev = NULL;
+	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
+		pmc_next = pmc->next;
+		if (pmc->mca_sfmode == MCAST_INCLUDE) {
+			type = MLD2_BLOCK_OLD_SOURCES;
+			dtype = MLD2_BLOCK_OLD_SOURCES;
+			skb = add_grec(skb, pmc, type, 1, 0, 0);
+			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
+		}
+		if (pmc->mca_crcount) {
+			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
+				type = MLD2_CHANGE_TO_INCLUDE;
+				skb = add_grec(skb, pmc, type, 1, 0, 0);
+			}
+			pmc->mca_crcount--;
+			if (pmc->mca_crcount == 0) {
+				mld_clear_zeros(&pmc->mca_tomb);
+				mld_clear_zeros(&pmc->mca_sources);
+			}
+		}
+		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
+		    !pmc->mca_sources) {
+			if (pmc_prev)
+				pmc_prev->next = pmc_next;
+			else
+				idev->mc_tomb = pmc_next;
+			in6_dev_put(pmc->idev);
+			kfree(pmc);
+		} else
+			pmc_prev = pmc;
+	}
+	spin_unlock(&idev->mc_lock);
+
+	/* change recs */
+	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+		spin_lock_bh(&pmc->mca_lock);
+		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
+			type = MLD2_BLOCK_OLD_SOURCES;
+			dtype = MLD2_ALLOW_NEW_SOURCES;
+		} else {
+			type = MLD2_ALLOW_NEW_SOURCES;
+			dtype = MLD2_BLOCK_OLD_SOURCES;
+		}
+		skb = add_grec(skb, pmc, type, 0, 0, 0);
+		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
+
+		/* filter mode changes */
+		if (pmc->mca_crcount) {
+			if (pmc->mca_sfmode == MCAST_EXCLUDE)
+				type = MLD2_CHANGE_TO_EXCLUDE;
+			else
+				type = MLD2_CHANGE_TO_INCLUDE;
+			skb = add_grec(skb, pmc, type, 0, 0, 0);
+			pmc->mca_crcount--;
+		}
+		spin_unlock_bh(&pmc->mca_lock);
+	}
+	read_unlock_bh(&idev->lock);
+	if (!skb)
+		return;
+	(void) mld_sendpack(skb);
+}
+
+static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
+{
+	struct net *net = dev_net(dev);
+	struct sock *sk = net->ipv6.igmp_sk;
+	struct inet6_dev *idev;
+	struct sk_buff *skb;
+	struct mld_msg *hdr;
+	const struct in6_addr *snd_addr, *saddr;
+	struct in6_addr addr_buf;
+	int hlen = LL_RESERVED_SPACE(dev);
+	int tlen = dev->needed_tailroom;
+	int err, len, payload_len, full_len;
+	u8 ra[8] = { IPPROTO_ICMPV6, 0,
+		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
+		     IPV6_TLV_PADN, 0 };
+	struct flowi6 fl6;
+	struct dst_entry *dst;
+
+	if (type == ICMPV6_MGM_REDUCTION)
+		snd_addr = &in6addr_linklocal_allrouters;
+	else
+		snd_addr = addr;
+
+	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
+	payload_len = len + sizeof(ra);
+	full_len = sizeof(struct ipv6hdr) + payload_len;
+
+	rcu_read_lock();
+	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
+		      IPSTATS_MIB_OUT, full_len);
+	rcu_read_unlock();
+
+	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
+
+	if (!skb) {
+		rcu_read_lock();
+		IP6_INC_STATS(net, __in6_dev_get(dev),
+			      IPSTATS_MIB_OUTDISCARDS);
+		rcu_read_unlock();
+		return;
+	}
+	skb->priority = TC_PRIO_CONTROL;
+	skb_reserve(skb, hlen);
+
+	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
+		/* <draft-ietf-magma-mld-source-05.txt>:
+		 * use unspecified address as the source address
+		 * when a valid link-local address is not available.
+		 */
+		saddr = &in6addr_any;
+	} else
+		saddr = &addr_buf;
+
+	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
+
+	skb_put_data(skb, ra, sizeof(ra));
+
+	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
+	hdr->mld_type = type;
+	hdr->mld_mca = *addr;
+
+	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
+					 IPPROTO_ICMPV6,
+					 csum_partial(hdr, len, 0));
+
+	rcu_read_lock();
+	idev = __in6_dev_get(skb->dev);
+
+	icmpv6_flow_init(sk, &fl6, type,
+			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
+			 skb->dev->ifindex);
+	dst = icmp6_dst_alloc(skb->dev, &fl6);
+	if (IS_ERR(dst)) {
+		err = PTR_ERR(dst);
+		goto err_out;
+	}
+
+	skb_dst_set(skb, dst);
+	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
+		      net, sk, skb, NULL, skb->dev,
+		      dst_output);
+out:
+	if (!err) {
+		ICMP6MSGOUT_INC_STATS(net, idev, type);
+		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
+	} else
+		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
+
+	rcu_read_unlock();
+	return;
+
+err_out:
+	kfree_skb(skb);
+	goto out;
+}
+
+static void mld_send_initial_cr(struct inet6_dev *idev)
+{
+	struct sk_buff *skb;
+	struct ifmcaddr6 *pmc;
+	int type;
+
+	if (mld_in_v1_mode(idev))
+		return;
+
+	skb = NULL;
+	read_lock_bh(&idev->lock);
+	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+		spin_lock_bh(&pmc->mca_lock);
+		if (pmc->mca_sfcount[MCAST_EXCLUDE])
+			type = MLD2_CHANGE_TO_EXCLUDE;
+		else
+			type = MLD2_ALLOW_NEW_SOURCES;
+		skb = add_grec(skb, pmc, type, 0, 0, 1);
+		spin_unlock_bh(&pmc->mca_lock);
+	}
+	read_unlock_bh(&idev->lock);
+	if (skb)
+		mld_sendpack(skb);
+}
+
+void ipv6_mc_dad_complete(struct inet6_dev *idev)
+{
+	idev->mc_dad_count = idev->mc_qrv;
+	if (idev->mc_dad_count) {
+		mld_send_initial_cr(idev);
+		idev->mc_dad_count--;
+		if (idev->mc_dad_count)
+			mld_dad_start_timer(idev,
+					    unsolicited_report_interval(idev));
+	}
+}
+
+static void mld_dad_timer_expire(struct timer_list *t)
+{
+	struct inet6_dev *idev = from_timer(idev, t, mc_dad_timer);
+
+	mld_send_initial_cr(idev);
+	if (idev->mc_dad_count) {
+		idev->mc_dad_count--;
+		if (idev->mc_dad_count)
+			mld_dad_start_timer(idev,
+					    unsolicited_report_interval(idev));
+	}
+	in6_dev_put(idev);
+}
+
+static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
+	const struct in6_addr *psfsrc)
+{
+	struct ip6_sf_list *psf, *psf_prev;
+	int rv = 0;
+
+	psf_prev = NULL;
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
+			break;
+		psf_prev = psf;
+	}
+	if (!psf || psf->sf_count[sfmode] == 0) {
+		/* source filter not found, or count wrong =>  bug */
+		return -ESRCH;
+	}
+	psf->sf_count[sfmode]--;
+	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
+		struct inet6_dev *idev = pmc->idev;
+
+		/* no more filters for this source */
+		if (psf_prev)
+			psf_prev->sf_next = psf->sf_next;
+		else
+			pmc->mca_sources = psf->sf_next;
+		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
+		    !mld_in_v1_mode(idev)) {
+			psf->sf_crcount = idev->mc_qrv;
+			psf->sf_next = pmc->mca_tomb;
+			pmc->mca_tomb = psf;
+			rv = 1;
+		} else
+			kfree(psf);
+	}
+	return rv;
+}
+
+static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
+			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
+			  int delta)
+{
+	struct ifmcaddr6 *pmc;
+	int	changerec = 0;
+	int	i, err;
+
+	if (!idev)
+		return -ENODEV;
+	read_lock_bh(&idev->lock);
+	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
+			break;
+	}
+	if (!pmc) {
+		/* MCA not found?? bug */
+		read_unlock_bh(&idev->lock);
+		return -ESRCH;
+	}
+	spin_lock_bh(&pmc->mca_lock);
+	sf_markstate(pmc);
+	if (!delta) {
+		if (!pmc->mca_sfcount[sfmode]) {
+			spin_unlock_bh(&pmc->mca_lock);
+			read_unlock_bh(&idev->lock);
+			return -EINVAL;
+		}
+		pmc->mca_sfcount[sfmode]--;
+	}
+	err = 0;
+	for (i = 0; i < sfcount; i++) {
+		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
+
+		changerec |= rv > 0;
+		if (!err && rv < 0)
+			err = rv;
+	}
+	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
+	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
+	    pmc->mca_sfcount[MCAST_INCLUDE]) {
+		struct ip6_sf_list *psf;
+
+		/* filter mode change */
+		pmc->mca_sfmode = MCAST_INCLUDE;
+		pmc->mca_crcount = idev->mc_qrv;
+		idev->mc_ifc_count = pmc->mca_crcount;
+		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
+			psf->sf_crcount = 0;
+		mld_ifc_event(pmc->idev);
+	} else if (sf_setstate(pmc) || changerec)
+		mld_ifc_event(pmc->idev);
+	spin_unlock_bh(&pmc->mca_lock);
+	read_unlock_bh(&idev->lock);
+	return err;
+}
+
+/*
+ * Add multicast single-source filter to the interface list
+ */
+static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
+	const struct in6_addr *psfsrc)
+{
+	struct ip6_sf_list *psf, *psf_prev;
+
+	psf_prev = NULL;
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
+			break;
+		psf_prev = psf;
+	}
+	if (!psf) {
+		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
+		if (!psf)
+			return -ENOBUFS;
+
+		psf->sf_addr = *psfsrc;
+		if (psf_prev) {
+			psf_prev->sf_next = psf;
+		} else
+			pmc->mca_sources = psf;
+	}
+	psf->sf_count[sfmode]++;
+	return 0;
+}
+
+static void sf_markstate(struct ifmcaddr6 *pmc)
+{
+	struct ip6_sf_list *psf;
+	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
+
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
+		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
+			psf->sf_oldin = mca_xcount ==
+				psf->sf_count[MCAST_EXCLUDE] &&
+				!psf->sf_count[MCAST_INCLUDE];
+		} else
+			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
+}
+
+static int sf_setstate(struct ifmcaddr6 *pmc)
+{
+	struct ip6_sf_list *psf, *dpsf;
+	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
+	int qrv = pmc->idev->mc_qrv;
+	int new_in, rv;
+
+	rv = 0;
+	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
+		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
+			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
+				!psf->sf_count[MCAST_INCLUDE];
+		} else
+			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
+		if (new_in) {
+			if (!psf->sf_oldin) {
+				struct ip6_sf_list *prev = NULL;
+
+				for (dpsf = pmc->mca_tomb; dpsf;
+				     dpsf = dpsf->sf_next) {
+					if (ipv6_addr_equal(&dpsf->sf_addr,
+					    &psf->sf_addr))
+						break;
+					prev = dpsf;
+				}
+				if (dpsf) {
+					if (prev)
+						prev->sf_next = dpsf->sf_next;
+					else
+						pmc->mca_tomb = dpsf->sf_next;
+					kfree(dpsf);
+				}
+				psf->sf_crcount = qrv;
+				rv++;
+			}
+		} else if (psf->sf_oldin) {
+			psf->sf_crcount = 0;
+			/*
+			 * add or update "delete" records if an active filter
+			 * is now inactive
+			 */
+			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
+				if (ipv6_addr_equal(&dpsf->sf_addr,
+				    &psf->sf_addr))
+					break;
+			if (!dpsf) {
+				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
+				if (!dpsf)
+					continue;
+				*dpsf = *psf;
+				/* pmc->mca_lock held by callers */
+				dpsf->sf_next = pmc->mca_tomb;
+				pmc->mca_tomb = dpsf;
+			}
+			dpsf->sf_crcount = qrv;
+			rv++;
+		}
+	}
+	return rv;
+}
+
+/*
+ * Add multicast source filter list to the interface list
+ */
+static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
+			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
+			  int delta)
+{
+	struct ifmcaddr6 *pmc;
+	int	isexclude;
+	int	i, err;
+
+	if (!idev)
+		return -ENODEV;
+	read_lock_bh(&idev->lock);
+	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
+		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
+			break;
+	}
+	if (!pmc) {
+		/* MCA not found?? bug */
+		read_unlock_bh(&idev->lock);
+		return -ESRCH;
+	}
+	spin_lock_bh(&pmc->mca_lock);
+
+	sf_markstate(pmc);
+	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
+	if (!delta)
+		pmc->mca_sfcount[sfmode]++;
+	err = 0;
+	for (i = 0; i < sfcount; i++) {
+		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
+		if (err)
+			break;
+	}
+	if (err) {
+		int j;
+
+		if (!delta)
+			pmc->mca_sfcount[sfmode]--;
+		for (j = 0; j < i; j++)
+			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
+	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
+		struct ip6_sf_list *psf;
+
+		/* filter mode change */
+		if (pmc->mca_sfcount[MCAST_EXCLUDE])
+			pmc->mca_sfmode = MCAST_EXCLUDE;
+		else if (pmc->mca_sfcount[MCAST_INCLUDE])
+			pmc->mca_sfmode = MCAST_INCLUDE;
+		/* else no filters; keep old mode for reports */
+
+		pmc->mca_crcount = idev->mc_qrv;
+		idev->mc_ifc_count = pmc->mca_crcount;
+		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
+			psf->sf_crcount = 0;
+		mld_ifc_event(idev);
+	} else if (sf_setstate(pmc))
+		mld_ifc_event(idev);
+	spin_unlock_bh(&pmc->mca_lock);
+	read_unlock_bh(&idev->lock);
+	return err;
+}
+
+static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
+{
+	struct ip6_sf_list *psf, *nextpsf;
+
+	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
+		nextpsf = psf->sf_next;
+		kfree(psf);
+	}
+	pmc->mca_tomb = NULL;
+	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
+		nextpsf = psf->sf_next;
+		kfree(psf);
+	}
+	pmc->mca_sources = NULL;
+	pmc->mca_sfmode = MCAST_EXCLUDE;
+	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
+	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
+}
+
+
+static void igmp6_join_group(struct ifmcaddr6 *ma)
+{
+	unsigned long delay;
+
+	if (ma->mca_flags & MAF_NOREPORT)
+		return;
+
+	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
+
+	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
+
+	spin_lock_bh(&ma->mca_lock);
+	if (del_timer(&ma->mca_timer)) {
+		refcount_dec(&ma->mca_refcnt);
+		delay = ma->mca_timer.expires - jiffies;
+	}
+
+	if (!mod_timer(&ma->mca_timer, jiffies + delay))
+		refcount_inc(&ma->mca_refcnt);
+	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
+	spin_unlock_bh(&ma->mca_lock);
+}
+
+static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
+			    struct inet6_dev *idev)
+{
+	int err;
+
+	write_lock_bh(&iml->sflock);
+	if (!iml->sflist) {
+		/* any-source empty exclude case */
+		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
+	} else {
+		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
+				iml->sflist->sl_count, iml->sflist->sl_addr, 0);
+		sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
+		iml->sflist = NULL;
+	}
+	write_unlock_bh(&iml->sflock);
+	return err;
+}
+
+static void igmp6_leave_group(struct ifmcaddr6 *ma)
+{
+	if (mld_in_v1_mode(ma->idev)) {
+		if (ma->mca_flags & MAF_LAST_REPORTER)
+			igmp6_send(&ma->mca_addr, ma->idev->dev,
+				ICMPV6_MGM_REDUCTION);
+	} else {
+		mld_add_delrec(ma->idev, ma);
+		mld_ifc_event(ma->idev);
+	}
+}
+
+static void mld_gq_timer_expire(struct timer_list *t)
+{
+	struct inet6_dev *idev = from_timer(idev, t, mc_gq_timer);
+
+	idev->mc_gq_running = 0;
+	mld_send_report(idev, NULL);
+	in6_dev_put(idev);
+}
+
+static void mld_ifc_timer_expire(struct timer_list *t)
+{
+	struct inet6_dev *idev = from_timer(idev, t, mc_ifc_timer);
+
+	mld_send_cr(idev);
+	if (idev->mc_ifc_count) {
+		idev->mc_ifc_count--;
+		if (idev->mc_ifc_count)
+			mld_ifc_start_timer(idev,
+					    unsolicited_report_interval(idev));
+	}
+	in6_dev_put(idev);
+}
+
+static void mld_ifc_event(struct inet6_dev *idev)
+{
+	if (mld_in_v1_mode(idev))
+		return;
+	idev->mc_ifc_count = idev->mc_qrv;
+	mld_ifc_start_timer(idev, 1);
+}
+
+static void igmp6_timer_handler(struct timer_list *t)
+{
+	struct ifmcaddr6 *ma = from_timer(ma, t, mca_timer);
+
+	if (mld_in_v1_mode(ma->idev))
+		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
+	else
+		mld_send_report(ma->idev, ma);
+
+	spin_lock(&ma->mca_lock);
+	ma->mca_flags |=  MAF_LAST_REPORTER;
+	ma->mca_flags &= ~MAF_TIMER_RUNNING;
+	spin_unlock(&ma->mca_lock);
+	ma_put(ma);
+}
+
+/* Device changing type */
+
+void ipv6_mc_unmap(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *i;
+
+	/* Install multicast list, except for all-nodes (already installed) */
+
+	read_lock_bh(&idev->lock);
+	for (i = idev->mc_list; i; i = i->next)
+		igmp6_group_dropped(i);
+	read_unlock_bh(&idev->lock);
+}
+
+void ipv6_mc_remap(struct inet6_dev *idev)
+{
+	ipv6_mc_up(idev);
+}
+
+/* Device going down */
+
+void ipv6_mc_down(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *i;
+
+	/* Withdraw multicast list */
+
+	read_lock_bh(&idev->lock);
+
+	for (i = idev->mc_list; i; i = i->next)
+		igmp6_group_dropped(i);
+
+	/* Should stop timer after group drop. or we will
+	 * start timer again in mld_ifc_event()
+	 */
+	mld_ifc_stop_timer(idev);
+	mld_gq_stop_timer(idev);
+	mld_dad_stop_timer(idev);
+	read_unlock_bh(&idev->lock);
+}
+
+static void ipv6_mc_reset(struct inet6_dev *idev)
+{
+	idev->mc_qrv = sysctl_mld_qrv;
+	idev->mc_qi = MLD_QI_DEFAULT;
+	idev->mc_qri = MLD_QRI_DEFAULT;
+	idev->mc_v1_seen = 0;
+	idev->mc_maxdelay = unsolicited_report_interval(idev);
+}
+
+/* Device going up */
+
+void ipv6_mc_up(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *i;
+
+	/* Install multicast list, except for all-nodes (already installed) */
+
+	read_lock_bh(&idev->lock);
+	ipv6_mc_reset(idev);
+	for (i = idev->mc_list; i; i = i->next) {
+		mld_del_delrec(idev, i);
+		igmp6_group_added(i);
+	}
+	read_unlock_bh(&idev->lock);
+}
+
+/* IPv6 device initialization. */
+
+void ipv6_mc_init_dev(struct inet6_dev *idev)
+{
+	write_lock_bh(&idev->lock);
+	spin_lock_init(&idev->mc_lock);
+	idev->mc_gq_running = 0;
+	timer_setup(&idev->mc_gq_timer, mld_gq_timer_expire, 0);
+	idev->mc_tomb = NULL;
+	idev->mc_ifc_count = 0;
+	timer_setup(&idev->mc_ifc_timer, mld_ifc_timer_expire, 0);
+	timer_setup(&idev->mc_dad_timer, mld_dad_timer_expire, 0);
+	ipv6_mc_reset(idev);
+	write_unlock_bh(&idev->lock);
+}
+
+/*
+ *	Device is about to be destroyed: clean up.
+ */
+
+void ipv6_mc_destroy_dev(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *i;
+
+	/* Deactivate timers */
+	ipv6_mc_down(idev);
+	mld_clear_delrec(idev);
+
+	/* Delete all-nodes address. */
+	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
+	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
+	 * fail.
+	 */
+	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
+
+	if (idev->cnf.forwarding)
+		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
+
+	write_lock_bh(&idev->lock);
+	while ((i = idev->mc_list) != NULL) {
+		idev->mc_list = i->next;
+
+		write_unlock_bh(&idev->lock);
+		ip6_mc_clear_src(i);
+		ma_put(i);
+		write_lock_bh(&idev->lock);
+	}
+	write_unlock_bh(&idev->lock);
+}
+
+static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
+{
+	struct ifmcaddr6 *pmc;
+
+	ASSERT_RTNL();
+
+	if (mld_in_v1_mode(idev)) {
+		read_lock_bh(&idev->lock);
+		for (pmc = idev->mc_list; pmc; pmc = pmc->next)
+			igmp6_join_group(pmc);
+		read_unlock_bh(&idev->lock);
+	} else
+		mld_send_report(idev, NULL);
+}
+
+static int ipv6_mc_netdev_event(struct notifier_block *this,
+				unsigned long event,
+				void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct inet6_dev *idev = __in6_dev_get(dev);
+
+	switch (event) {
+	case NETDEV_RESEND_IGMP:
+		if (idev)
+			ipv6_mc_rejoin_groups(idev);
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block igmp6_netdev_notifier = {
+	.notifier_call = ipv6_mc_netdev_event,
+};
+
+#ifdef CONFIG_PROC_FS
+struct igmp6_mc_iter_state {
+	struct seq_net_private p;
+	struct net_device *dev;
+	struct inet6_dev *idev;
+};
+
+#define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
+
+static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
+{
+	struct ifmcaddr6 *im = NULL;
+	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
+	struct net *net = seq_file_net(seq);
+
+	state->idev = NULL;
+	for_each_netdev_rcu(net, state->dev) {
+		struct inet6_dev *idev;
+		idev = __in6_dev_get(state->dev);
+		if (!idev)
+			continue;
+		read_lock_bh(&idev->lock);
+		im = idev->mc_list;
+		if (im) {
+			state->idev = idev;
+			break;
+		}
+		read_unlock_bh(&idev->lock);
+	}
+	return im;
+}
+
+static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
+{
+	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
+
+	im = im->next;
+	while (!im) {
+		if (likely(state->idev))
+			read_unlock_bh(&state->idev->lock);
+
+		state->dev = next_net_device_rcu(state->dev);
+		if (!state->dev) {
+			state->idev = NULL;
+			break;
+		}
+		state->idev = __in6_dev_get(state->dev);
+		if (!state->idev)
+			continue;
+		read_lock_bh(&state->idev->lock);
+		im = state->idev->mc_list;
+	}
+	return im;
+}
+
+static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
+	if (im)
+		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
+			--pos;
+	return pos ? NULL : im;
+}
+
+static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(RCU)
+{
+	rcu_read_lock();
+	return igmp6_mc_get_idx(seq, *pos);
+}
+
+static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
+
+	++*pos;
+	return im;
+}
+
+static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
+	__releases(RCU)
+{
+	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
+
+	if (likely(state->idev)) {
+		read_unlock_bh(&state->idev->lock);
+		state->idev = NULL;
+	}
+	state->dev = NULL;
+	rcu_read_unlock();
+}
+
+static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
+{
+	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
+	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
+
+	seq_printf(seq,
+		   "%-4d %-15s %pi6 %5d %08X %ld\n",
+		   state->dev->ifindex, state->dev->name,
+		   &im->mca_addr,
+		   im->mca_users, im->mca_flags,
+		   (im->mca_flags&MAF_TIMER_RUNNING) ?
+		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
+	return 0;
+}
+
+static const struct seq_operations igmp6_mc_seq_ops = {
+	.start	=	igmp6_mc_seq_start,
+	.next	=	igmp6_mc_seq_next,
+	.stop	=	igmp6_mc_seq_stop,
+	.show	=	igmp6_mc_seq_show,
+};
+
+struct igmp6_mcf_iter_state {
+	struct seq_net_private p;
+	struct net_device *dev;
+	struct inet6_dev *idev;
+	struct ifmcaddr6 *im;
+};
+
+#define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
+
+static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
+{
+	struct ip6_sf_list *psf = NULL;
+	struct ifmcaddr6 *im = NULL;
+	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
+	struct net *net = seq_file_net(seq);
+
+	state->idev = NULL;
+	state->im = NULL;
+	for_each_netdev_rcu(net, state->dev) {
+		struct inet6_dev *idev;
+		idev = __in6_dev_get(state->dev);
+		if (unlikely(idev == NULL))
+			continue;
+		read_lock_bh(&idev->lock);
+		im = idev->mc_list;
+		if (likely(im)) {
+			spin_lock_bh(&im->mca_lock);
+			psf = im->mca_sources;
+			if (likely(psf)) {
+				state->im = im;
+				state->idev = idev;
+				break;
+			}
+			spin_unlock_bh(&im->mca_lock);
+		}
+		read_unlock_bh(&idev->lock);
+	}
+	return psf;
+}
+
+static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
+{
+	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
+
+	psf = psf->sf_next;
+	while (!psf) {
+		spin_unlock_bh(&state->im->mca_lock);
+		state->im = state->im->next;
+		while (!state->im) {
+			if (likely(state->idev))
+				read_unlock_bh(&state->idev->lock);
+
+			state->dev = next_net_device_rcu(state->dev);
+			if (!state->dev) {
+				state->idev = NULL;
+				goto out;
+			}
+			state->idev = __in6_dev_get(state->dev);
+			if (!state->idev)
+				continue;
+			read_lock_bh(&state->idev->lock);
+			state->im = state->idev->mc_list;
+		}
+		if (!state->im)
+			break;
+		spin_lock_bh(&state->im->mca_lock);
+		psf = state->im->mca_sources;
+	}
+out:
+	return psf;
+}
+
+static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
+	if (psf)
+		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
+			--pos;
+	return pos ? NULL : psf;
+}
+
+static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(RCU)
+{
+	rcu_read_lock();
+	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct ip6_sf_list *psf;
+	if (v == SEQ_START_TOKEN)
+		psf = igmp6_mcf_get_first(seq);
+	else
+		psf = igmp6_mcf_get_next(seq, v);
+	++*pos;
+	return psf;
+}
+
+static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
+	__releases(RCU)
+{
+	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
+	if (likely(state->im)) {
+		spin_unlock_bh(&state->im->mca_lock);
+		state->im = NULL;
+	}
+	if (likely(state->idev)) {
+		read_unlock_bh(&state->idev->lock);
+		state->idev = NULL;
+	}
+	state->dev = NULL;
+	rcu_read_unlock();
+}
+
+static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
+{
+	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
+	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
+
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
+	} else {
+		seq_printf(seq,
+			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
+			   state->dev->ifindex, state->dev->name,
+			   &state->im->mca_addr,
+			   &psf->sf_addr,
+			   psf->sf_count[MCAST_INCLUDE],
+			   psf->sf_count[MCAST_EXCLUDE]);
+	}
+	return 0;
+}
+
+static const struct seq_operations igmp6_mcf_seq_ops = {
+	.start	=	igmp6_mcf_seq_start,
+	.next	=	igmp6_mcf_seq_next,
+	.stop	=	igmp6_mcf_seq_stop,
+	.show	=	igmp6_mcf_seq_show,
+};
+
+static int __net_init igmp6_proc_init(struct net *net)
+{
+	int err;
+
+	err = -ENOMEM;
+	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
+			sizeof(struct igmp6_mc_iter_state)))
+		goto out;
+	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
+			&igmp6_mcf_seq_ops,
+			sizeof(struct igmp6_mcf_iter_state)))
+		goto out_proc_net_igmp6;
+
+	err = 0;
+out:
+	return err;
+
+out_proc_net_igmp6:
+	remove_proc_entry("igmp6", net->proc_net);
+	goto out;
+}
+
+static void __net_exit igmp6_proc_exit(struct net *net)
+{
+	remove_proc_entry("mcfilter6", net->proc_net);
+	remove_proc_entry("igmp6", net->proc_net);
+}
+#else
+static inline int igmp6_proc_init(struct net *net)
+{
+	return 0;
+}
+static inline void igmp6_proc_exit(struct net *net)
+{
+}
+#endif
+
+static int __net_init igmp6_net_init(struct net *net)
+{
+	int err;
+
+	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
+				   SOCK_RAW, IPPROTO_ICMPV6, net);
+	if (err < 0) {
+		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
+		       err);
+		goto out;
+	}
+
+	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
+
+	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
+				   SOCK_RAW, IPPROTO_ICMPV6, net);
+	if (err < 0) {
+		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
+		       err);
+		goto out_sock_create;
+	}
+
+	err = igmp6_proc_init(net);
+	if (err)
+		goto out_sock_create_autojoin;
+
+	return 0;
+
+out_sock_create_autojoin:
+	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
+out_sock_create:
+	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
+out:
+	return err;
+}
+
+static void __net_exit igmp6_net_exit(struct net *net)
+{
+	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
+	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
+	igmp6_proc_exit(net);
+}
+
+static struct pernet_operations igmp6_net_ops = {
+	.init = igmp6_net_init,
+	.exit = igmp6_net_exit,
+};
+
+int __init igmp6_init(void)
+{
+	return register_pernet_subsys(&igmp6_net_ops);
+}
+
+int __init igmp6_late_init(void)
+{
+	return register_netdevice_notifier(&igmp6_netdev_notifier);
+}
+
+void igmp6_cleanup(void)
+{
+	unregister_pernet_subsys(&igmp6_net_ops);
+}
+
+void igmp6_late_cleanup(void)
+{
+	unregister_netdevice_notifier(&igmp6_netdev_notifier);
+}