xref: /linux/net/ipv6/mcast.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Multicast support for IPv6
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *
9  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
10  */
11 
12 /* Changes:
13  *
14  *	yoshfuji	: fix format of router-alert option
15  *	YOSHIFUJI Hideaki @USAGI:
16  *		Fixed source address for MLD message based on
17  *		<draft-ietf-magma-mld-source-05.txt>.
18  *	YOSHIFUJI Hideaki @USAGI:
19  *		- Ignore Queries for invalid addresses.
20  *		- MLD for link-local addresses.
21  *	David L Stevens <dlstevens@us.ibm.com>:
22  *		- MLDv2 support
23  */
24 
25 #include <linux/module.h>
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/jiffies.h>
32 #include <linux/times.h>
33 #include <linux/net.h>
34 #include <linux/in.h>
35 #include <linux/in6.h>
36 #include <linux/netdevice.h>
37 #include <linux/if_arp.h>
38 #include <linux/route.h>
39 #include <linux/init.h>
40 #include <linux/proc_fs.h>
41 #include <linux/seq_file.h>
42 #include <linux/slab.h>
43 #include <linux/pkt_sched.h>
44 #include <net/mld.h>
45 
46 #include <linux/netfilter.h>
47 #include <linux/netfilter_ipv6.h>
48 
49 #include <net/net_namespace.h>
50 #include <net/sock.h>
51 #include <net/snmp.h>
52 
53 #include <net/ipv6.h>
54 #include <net/protocol.h>
55 #include <net/if_inet6.h>
56 #include <net/ndisc.h>
57 #include <net/addrconf.h>
58 #include <net/ip6_route.h>
59 #include <net/inet_common.h>
60 
61 #include <net/ip6_checksum.h>
62 
63 /* Ensure that we have struct in6_addr aligned on 32bit word. */
64 static int __mld2_query_bugs[] __attribute__((__unused__)) = {
65 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
66 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
67 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_grec, grec_mca) % 4)
68 };
69 
70 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
71 
72 static void igmp6_join_group(struct ifmcaddr6 *ma);
73 static void igmp6_leave_group(struct ifmcaddr6 *ma);
74 static void igmp6_timer_handler(struct timer_list *t);
75 
76 static void mld_gq_timer_expire(struct timer_list *t);
77 static void mld_ifc_timer_expire(struct timer_list *t);
78 static void mld_ifc_event(struct inet6_dev *idev);
79 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
80 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
81 static void mld_clear_delrec(struct inet6_dev *idev);
82 static bool mld_in_v1_mode(const struct inet6_dev *idev);
83 static int sf_setstate(struct ifmcaddr6 *pmc);
84 static void sf_markstate(struct ifmcaddr6 *pmc);
85 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
86 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
87 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
88 			  int delta);
89 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
90 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
91 			  int delta);
92 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
93 			    struct inet6_dev *idev);
94 static int __ipv6_dev_mc_inc(struct net_device *dev,
95 			     const struct in6_addr *addr, unsigned int mode);
96 
97 #define MLD_QRV_DEFAULT		2
98 /* RFC3810, 9.2. Query Interval */
99 #define MLD_QI_DEFAULT		(125 * HZ)
100 /* RFC3810, 9.3. Query Response Interval */
101 #define MLD_QRI_DEFAULT		(10 * HZ)
102 
103 /* RFC3810, 8.1 Query Version Distinctions */
104 #define MLD_V1_QUERY_LEN	24
105 #define MLD_V2_QUERY_LEN_MIN	28
106 
107 #define IPV6_MLD_MAX_MSF	64
108 
109 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
110 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
111 
112 /*
113  *	socket join on multicast group
114  */
115 
116 #define for_each_pmc_rcu(np, pmc)				\
117 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
118 	     pmc != NULL;					\
119 	     pmc = rcu_dereference(pmc->next))
120 
121 static int unsolicited_report_interval(struct inet6_dev *idev)
122 {
123 	int iv;
124 
125 	if (mld_in_v1_mode(idev))
126 		iv = idev->cnf.mldv1_unsolicited_report_interval;
127 	else
128 		iv = idev->cnf.mldv2_unsolicited_report_interval;
129 
130 	return iv > 0 ? iv : 1;
131 }
132 
133 static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
134 			       const struct in6_addr *addr, unsigned int mode)
135 {
136 	struct net_device *dev = NULL;
137 	struct ipv6_mc_socklist *mc_lst;
138 	struct ipv6_pinfo *np = inet6_sk(sk);
139 	struct net *net = sock_net(sk);
140 	int err;
141 
142 	ASSERT_RTNL();
143 
144 	if (!ipv6_addr_is_multicast(addr))
145 		return -EINVAL;
146 
147 	rcu_read_lock();
148 	for_each_pmc_rcu(np, mc_lst) {
149 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
150 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
151 			rcu_read_unlock();
152 			return -EADDRINUSE;
153 		}
154 	}
155 	rcu_read_unlock();
156 
157 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
158 
159 	if (!mc_lst)
160 		return -ENOMEM;
161 
162 	mc_lst->next = NULL;
163 	mc_lst->addr = *addr;
164 
165 	if (ifindex == 0) {
166 		struct rt6_info *rt;
167 		rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
168 		if (rt) {
169 			dev = rt->dst.dev;
170 			ip6_rt_put(rt);
171 		}
172 	} else
173 		dev = __dev_get_by_index(net, ifindex);
174 
175 	if (!dev) {
176 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
177 		return -ENODEV;
178 	}
179 
180 	mc_lst->ifindex = dev->ifindex;
181 	mc_lst->sfmode = mode;
182 	rwlock_init(&mc_lst->sflock);
183 	mc_lst->sflist = NULL;
184 
185 	/*
186 	 *	now add/increase the group membership on the device
187 	 */
188 
189 	err = __ipv6_dev_mc_inc(dev, addr, mode);
190 
191 	if (err) {
192 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
193 		return err;
194 	}
195 
196 	mc_lst->next = np->ipv6_mc_list;
197 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
198 
199 	return 0;
200 }
201 
202 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
203 {
204 	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
205 }
206 EXPORT_SYMBOL(ipv6_sock_mc_join);
207 
208 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
209 			  const struct in6_addr *addr, unsigned int mode)
210 {
211 	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
212 }
213 
214 /*
215  *	socket leave on multicast group
216  */
217 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
218 {
219 	struct ipv6_pinfo *np = inet6_sk(sk);
220 	struct ipv6_mc_socklist *mc_lst;
221 	struct ipv6_mc_socklist __rcu **lnk;
222 	struct net *net = sock_net(sk);
223 
224 	ASSERT_RTNL();
225 
226 	if (!ipv6_addr_is_multicast(addr))
227 		return -EINVAL;
228 
229 	for (lnk = &np->ipv6_mc_list;
230 	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
231 	      lnk = &mc_lst->next) {
232 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
233 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
234 			struct net_device *dev;
235 
236 			*lnk = mc_lst->next;
237 
238 			dev = __dev_get_by_index(net, mc_lst->ifindex);
239 			if (dev) {
240 				struct inet6_dev *idev = __in6_dev_get(dev);
241 
242 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
243 				if (idev)
244 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
245 			} else
246 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
247 
248 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
249 			kfree_rcu(mc_lst, rcu);
250 			return 0;
251 		}
252 	}
253 
254 	return -EADDRNOTAVAIL;
255 }
256 EXPORT_SYMBOL(ipv6_sock_mc_drop);
257 
258 /* called with rcu_read_lock() */
259 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
260 					     const struct in6_addr *group,
261 					     int ifindex)
262 {
263 	struct net_device *dev = NULL;
264 	struct inet6_dev *idev = NULL;
265 
266 	if (ifindex == 0) {
267 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
268 
269 		if (rt) {
270 			dev = rt->dst.dev;
271 			ip6_rt_put(rt);
272 		}
273 	} else
274 		dev = dev_get_by_index_rcu(net, ifindex);
275 
276 	if (!dev)
277 		return NULL;
278 	idev = __in6_dev_get(dev);
279 	if (!idev)
280 		return NULL;
281 	read_lock_bh(&idev->lock);
282 	if (idev->dead) {
283 		read_unlock_bh(&idev->lock);
284 		return NULL;
285 	}
286 	return idev;
287 }
288 
289 void __ipv6_sock_mc_close(struct sock *sk)
290 {
291 	struct ipv6_pinfo *np = inet6_sk(sk);
292 	struct ipv6_mc_socklist *mc_lst;
293 	struct net *net = sock_net(sk);
294 
295 	ASSERT_RTNL();
296 
297 	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
298 		struct net_device *dev;
299 
300 		np->ipv6_mc_list = mc_lst->next;
301 
302 		dev = __dev_get_by_index(net, mc_lst->ifindex);
303 		if (dev) {
304 			struct inet6_dev *idev = __in6_dev_get(dev);
305 
306 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
307 			if (idev)
308 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
309 		} else
310 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
311 
312 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
313 		kfree_rcu(mc_lst, rcu);
314 	}
315 }
316 
317 void ipv6_sock_mc_close(struct sock *sk)
318 {
319 	struct ipv6_pinfo *np = inet6_sk(sk);
320 
321 	if (!rcu_access_pointer(np->ipv6_mc_list))
322 		return;
323 	rtnl_lock();
324 	__ipv6_sock_mc_close(sk);
325 	rtnl_unlock();
326 }
327 
328 int ip6_mc_source(int add, int omode, struct sock *sk,
329 	struct group_source_req *pgsr)
330 {
331 	struct in6_addr *source, *group;
332 	struct ipv6_mc_socklist *pmc;
333 	struct inet6_dev *idev;
334 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
335 	struct ip6_sf_socklist *psl;
336 	struct net *net = sock_net(sk);
337 	int i, j, rv;
338 	int leavegroup = 0;
339 	int pmclocked = 0;
340 	int err;
341 
342 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
343 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
344 
345 	if (!ipv6_addr_is_multicast(group))
346 		return -EINVAL;
347 
348 	rcu_read_lock();
349 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
350 	if (!idev) {
351 		rcu_read_unlock();
352 		return -ENODEV;
353 	}
354 
355 	err = -EADDRNOTAVAIL;
356 
357 	for_each_pmc_rcu(inet6, pmc) {
358 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
359 			continue;
360 		if (ipv6_addr_equal(&pmc->addr, group))
361 			break;
362 	}
363 	if (!pmc) {		/* must have a prior join */
364 		err = -EINVAL;
365 		goto done;
366 	}
367 	/* if a source filter was set, must be the same mode as before */
368 	if (pmc->sflist) {
369 		if (pmc->sfmode != omode) {
370 			err = -EINVAL;
371 			goto done;
372 		}
373 	} else if (pmc->sfmode != omode) {
374 		/* allow mode switches for empty-set filters */
375 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
376 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
377 		pmc->sfmode = omode;
378 	}
379 
380 	write_lock(&pmc->sflock);
381 	pmclocked = 1;
382 
383 	psl = pmc->sflist;
384 	if (!add) {
385 		if (!psl)
386 			goto done;	/* err = -EADDRNOTAVAIL */
387 		rv = !0;
388 		for (i = 0; i < psl->sl_count; i++) {
389 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
390 			if (rv == 0)
391 				break;
392 		}
393 		if (rv)		/* source not found */
394 			goto done;	/* err = -EADDRNOTAVAIL */
395 
396 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
397 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
398 			leavegroup = 1;
399 			goto done;
400 		}
401 
402 		/* update the interface filter */
403 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
404 
405 		for (j = i+1; j < psl->sl_count; j++)
406 			psl->sl_addr[j-1] = psl->sl_addr[j];
407 		psl->sl_count--;
408 		err = 0;
409 		goto done;
410 	}
411 	/* else, add a new source to the filter */
412 
413 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
414 		err = -ENOBUFS;
415 		goto done;
416 	}
417 	if (!psl || psl->sl_count == psl->sl_max) {
418 		struct ip6_sf_socklist *newpsl;
419 		int count = IP6_SFBLOCK;
420 
421 		if (psl)
422 			count += psl->sl_max;
423 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
424 		if (!newpsl) {
425 			err = -ENOBUFS;
426 			goto done;
427 		}
428 		newpsl->sl_max = count;
429 		newpsl->sl_count = count - IP6_SFBLOCK;
430 		if (psl) {
431 			for (i = 0; i < psl->sl_count; i++)
432 				newpsl->sl_addr[i] = psl->sl_addr[i];
433 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
434 		}
435 		pmc->sflist = psl = newpsl;
436 	}
437 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
438 	for (i = 0; i < psl->sl_count; i++) {
439 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
440 		if (rv == 0) /* There is an error in the address. */
441 			goto done;
442 	}
443 	for (j = psl->sl_count-1; j >= i; j--)
444 		psl->sl_addr[j+1] = psl->sl_addr[j];
445 	psl->sl_addr[i] = *source;
446 	psl->sl_count++;
447 	err = 0;
448 	/* update the interface list */
449 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
450 done:
451 	if (pmclocked)
452 		write_unlock(&pmc->sflock);
453 	read_unlock_bh(&idev->lock);
454 	rcu_read_unlock();
455 	if (leavegroup)
456 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
457 	return err;
458 }
459 
460 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
461 {
462 	const struct in6_addr *group;
463 	struct ipv6_mc_socklist *pmc;
464 	struct inet6_dev *idev;
465 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
466 	struct ip6_sf_socklist *newpsl, *psl;
467 	struct net *net = sock_net(sk);
468 	int leavegroup = 0;
469 	int i, err;
470 
471 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
472 
473 	if (!ipv6_addr_is_multicast(group))
474 		return -EINVAL;
475 	if (gsf->gf_fmode != MCAST_INCLUDE &&
476 	    gsf->gf_fmode != MCAST_EXCLUDE)
477 		return -EINVAL;
478 
479 	rcu_read_lock();
480 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
481 
482 	if (!idev) {
483 		rcu_read_unlock();
484 		return -ENODEV;
485 	}
486 
487 	err = 0;
488 
489 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
490 		leavegroup = 1;
491 		goto done;
492 	}
493 
494 	for_each_pmc_rcu(inet6, pmc) {
495 		if (pmc->ifindex != gsf->gf_interface)
496 			continue;
497 		if (ipv6_addr_equal(&pmc->addr, group))
498 			break;
499 	}
500 	if (!pmc) {		/* must have a prior join */
501 		err = -EINVAL;
502 		goto done;
503 	}
504 	if (gsf->gf_numsrc) {
505 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
506 							  GFP_ATOMIC);
507 		if (!newpsl) {
508 			err = -ENOBUFS;
509 			goto done;
510 		}
511 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
512 		for (i = 0; i < newpsl->sl_count; ++i) {
513 			struct sockaddr_in6 *psin6;
514 
515 			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
516 			newpsl->sl_addr[i] = psin6->sin6_addr;
517 		}
518 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
519 			newpsl->sl_count, newpsl->sl_addr, 0);
520 		if (err) {
521 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
522 			goto done;
523 		}
524 	} else {
525 		newpsl = NULL;
526 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
527 	}
528 
529 	write_lock(&pmc->sflock);
530 	psl = pmc->sflist;
531 	if (psl) {
532 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
533 			psl->sl_count, psl->sl_addr, 0);
534 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
535 	} else
536 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
537 	pmc->sflist = newpsl;
538 	pmc->sfmode = gsf->gf_fmode;
539 	write_unlock(&pmc->sflock);
540 	err = 0;
541 done:
542 	read_unlock_bh(&idev->lock);
543 	rcu_read_unlock();
544 	if (leavegroup)
545 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
546 	return err;
547 }
548 
549 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
550 	struct group_filter __user *optval, int __user *optlen)
551 {
552 	int err, i, count, copycount;
553 	const struct in6_addr *group;
554 	struct ipv6_mc_socklist *pmc;
555 	struct inet6_dev *idev;
556 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
557 	struct ip6_sf_socklist *psl;
558 	struct net *net = sock_net(sk);
559 
560 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
561 
562 	if (!ipv6_addr_is_multicast(group))
563 		return -EINVAL;
564 
565 	rcu_read_lock();
566 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
567 
568 	if (!idev) {
569 		rcu_read_unlock();
570 		return -ENODEV;
571 	}
572 
573 	err = -EADDRNOTAVAIL;
574 	/* changes to the ipv6_mc_list require the socket lock and
575 	 * rtnl lock. We have the socket lock and rcu read lock,
576 	 * so reading the list is safe.
577 	 */
578 
579 	for_each_pmc_rcu(inet6, pmc) {
580 		if (pmc->ifindex != gsf->gf_interface)
581 			continue;
582 		if (ipv6_addr_equal(group, &pmc->addr))
583 			break;
584 	}
585 	if (!pmc)		/* must have a prior join */
586 		goto done;
587 	gsf->gf_fmode = pmc->sfmode;
588 	psl = pmc->sflist;
589 	count = psl ? psl->sl_count : 0;
590 	read_unlock_bh(&idev->lock);
591 	rcu_read_unlock();
592 
593 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
594 	gsf->gf_numsrc = count;
595 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
596 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
597 		return -EFAULT;
598 	}
599 	/* changes to psl require the socket lock, and a write lock
600 	 * on pmc->sflock. We have the socket lock so reading here is safe.
601 	 */
602 	for (i = 0; i < copycount; i++) {
603 		struct sockaddr_in6 *psin6;
604 		struct sockaddr_storage ss;
605 
606 		psin6 = (struct sockaddr_in6 *)&ss;
607 		memset(&ss, 0, sizeof(ss));
608 		psin6->sin6_family = AF_INET6;
609 		psin6->sin6_addr = psl->sl_addr[i];
610 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
611 			return -EFAULT;
612 	}
613 	return 0;
614 done:
615 	read_unlock_bh(&idev->lock);
616 	rcu_read_unlock();
617 	return err;
618 }
619 
620 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
621 		    const struct in6_addr *src_addr)
622 {
623 	struct ipv6_pinfo *np = inet6_sk(sk);
624 	struct ipv6_mc_socklist *mc;
625 	struct ip6_sf_socklist *psl;
626 	bool rv = true;
627 
628 	rcu_read_lock();
629 	for_each_pmc_rcu(np, mc) {
630 		if (ipv6_addr_equal(&mc->addr, mc_addr))
631 			break;
632 	}
633 	if (!mc) {
634 		rcu_read_unlock();
635 		return np->mc_all;
636 	}
637 	read_lock(&mc->sflock);
638 	psl = mc->sflist;
639 	if (!psl) {
640 		rv = mc->sfmode == MCAST_EXCLUDE;
641 	} else {
642 		int i;
643 
644 		for (i = 0; i < psl->sl_count; i++) {
645 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
646 				break;
647 		}
648 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
649 			rv = false;
650 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
651 			rv = false;
652 	}
653 	read_unlock(&mc->sflock);
654 	rcu_read_unlock();
655 
656 	return rv;
657 }
658 
659 static void igmp6_group_added(struct ifmcaddr6 *mc)
660 {
661 	struct net_device *dev = mc->idev->dev;
662 	char buf[MAX_ADDR_LEN];
663 
664 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
665 	    IPV6_ADDR_SCOPE_LINKLOCAL)
666 		return;
667 
668 	spin_lock_bh(&mc->mca_lock);
669 	if (!(mc->mca_flags&MAF_LOADED)) {
670 		mc->mca_flags |= MAF_LOADED;
671 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
672 			dev_mc_add(dev, buf);
673 	}
674 	spin_unlock_bh(&mc->mca_lock);
675 
676 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
677 		return;
678 
679 	if (mld_in_v1_mode(mc->idev)) {
680 		igmp6_join_group(mc);
681 		return;
682 	}
683 	/* else v2 */
684 
685 	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
686 	 * should not send filter-mode change record as the mode
687 	 * should be from IN() to IN(A).
688 	 */
689 	if (mc->mca_sfmode == MCAST_EXCLUDE)
690 		mc->mca_crcount = mc->idev->mc_qrv;
691 
692 	mld_ifc_event(mc->idev);
693 }
694 
695 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
696 {
697 	struct net_device *dev = mc->idev->dev;
698 	char buf[MAX_ADDR_LEN];
699 
700 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
701 	    IPV6_ADDR_SCOPE_LINKLOCAL)
702 		return;
703 
704 	spin_lock_bh(&mc->mca_lock);
705 	if (mc->mca_flags&MAF_LOADED) {
706 		mc->mca_flags &= ~MAF_LOADED;
707 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
708 			dev_mc_del(dev, buf);
709 	}
710 
711 	spin_unlock_bh(&mc->mca_lock);
712 	if (mc->mca_flags & MAF_NOREPORT)
713 		return;
714 
715 	if (!mc->idev->dead)
716 		igmp6_leave_group(mc);
717 
718 	spin_lock_bh(&mc->mca_lock);
719 	if (del_timer(&mc->mca_timer))
720 		refcount_dec(&mc->mca_refcnt);
721 	spin_unlock_bh(&mc->mca_lock);
722 }
723 
724 /*
725  * deleted ifmcaddr6 manipulation
726  */
727 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
728 {
729 	struct ifmcaddr6 *pmc;
730 
731 	/* this is an "ifmcaddr6" for convenience; only the fields below
732 	 * are actually used. In particular, the refcnt and users are not
733 	 * used for management of the delete list. Using the same structure
734 	 * for deleted items allows change reports to use common code with
735 	 * non-deleted or query-response MCA's.
736 	 */
737 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
738 	if (!pmc)
739 		return;
740 
741 	spin_lock_bh(&im->mca_lock);
742 	spin_lock_init(&pmc->mca_lock);
743 	pmc->idev = im->idev;
744 	in6_dev_hold(idev);
745 	pmc->mca_addr = im->mca_addr;
746 	pmc->mca_crcount = idev->mc_qrv;
747 	pmc->mca_sfmode = im->mca_sfmode;
748 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
749 		struct ip6_sf_list *psf;
750 
751 		pmc->mca_tomb = im->mca_tomb;
752 		pmc->mca_sources = im->mca_sources;
753 		im->mca_tomb = im->mca_sources = NULL;
754 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
755 			psf->sf_crcount = pmc->mca_crcount;
756 	}
757 	spin_unlock_bh(&im->mca_lock);
758 
759 	spin_lock_bh(&idev->mc_lock);
760 	pmc->next = idev->mc_tomb;
761 	idev->mc_tomb = pmc;
762 	spin_unlock_bh(&idev->mc_lock);
763 }
764 
765 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
766 {
767 	struct ifmcaddr6 *pmc, *pmc_prev;
768 	struct ip6_sf_list *psf;
769 	struct in6_addr *pmca = &im->mca_addr;
770 
771 	spin_lock_bh(&idev->mc_lock);
772 	pmc_prev = NULL;
773 	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
774 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
775 			break;
776 		pmc_prev = pmc;
777 	}
778 	if (pmc) {
779 		if (pmc_prev)
780 			pmc_prev->next = pmc->next;
781 		else
782 			idev->mc_tomb = pmc->next;
783 	}
784 	spin_unlock_bh(&idev->mc_lock);
785 
786 	spin_lock_bh(&im->mca_lock);
787 	if (pmc) {
788 		im->idev = pmc->idev;
789 		if (im->mca_sfmode == MCAST_INCLUDE) {
790 			im->mca_tomb = pmc->mca_tomb;
791 			im->mca_sources = pmc->mca_sources;
792 			for (psf = im->mca_sources; psf; psf = psf->sf_next)
793 				psf->sf_crcount = idev->mc_qrv;
794 		} else {
795 			im->mca_crcount = idev->mc_qrv;
796 		}
797 		in6_dev_put(pmc->idev);
798 		kfree(pmc);
799 	}
800 	spin_unlock_bh(&im->mca_lock);
801 }
802 
803 static void mld_clear_delrec(struct inet6_dev *idev)
804 {
805 	struct ifmcaddr6 *pmc, *nextpmc;
806 
807 	spin_lock_bh(&idev->mc_lock);
808 	pmc = idev->mc_tomb;
809 	idev->mc_tomb = NULL;
810 	spin_unlock_bh(&idev->mc_lock);
811 
812 	for (; pmc; pmc = nextpmc) {
813 		nextpmc = pmc->next;
814 		ip6_mc_clear_src(pmc);
815 		in6_dev_put(pmc->idev);
816 		kfree(pmc);
817 	}
818 
819 	/* clear dead sources, too */
820 	read_lock_bh(&idev->lock);
821 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
822 		struct ip6_sf_list *psf, *psf_next;
823 
824 		spin_lock_bh(&pmc->mca_lock);
825 		psf = pmc->mca_tomb;
826 		pmc->mca_tomb = NULL;
827 		spin_unlock_bh(&pmc->mca_lock);
828 		for (; psf; psf = psf_next) {
829 			psf_next = psf->sf_next;
830 			kfree(psf);
831 		}
832 	}
833 	read_unlock_bh(&idev->lock);
834 }
835 
836 static void mca_get(struct ifmcaddr6 *mc)
837 {
838 	refcount_inc(&mc->mca_refcnt);
839 }
840 
841 static void ma_put(struct ifmcaddr6 *mc)
842 {
843 	if (refcount_dec_and_test(&mc->mca_refcnt)) {
844 		in6_dev_put(mc->idev);
845 		kfree(mc);
846 	}
847 }
848 
849 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
850 				   const struct in6_addr *addr,
851 				   unsigned int mode)
852 {
853 	struct ifmcaddr6 *mc;
854 
855 	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
856 	if (!mc)
857 		return NULL;
858 
859 	timer_setup(&mc->mca_timer, igmp6_timer_handler, 0);
860 
861 	mc->mca_addr = *addr;
862 	mc->idev = idev; /* reference taken by caller */
863 	mc->mca_users = 1;
864 	/* mca_stamp should be updated upon changes */
865 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
866 	refcount_set(&mc->mca_refcnt, 1);
867 	spin_lock_init(&mc->mca_lock);
868 
869 	mc->mca_sfmode = mode;
870 	mc->mca_sfcount[mode] = 1;
871 
872 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
873 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
874 		mc->mca_flags |= MAF_NOREPORT;
875 
876 	return mc;
877 }
878 
879 /*
880  *	device multicast group inc (add if not found)
881  */
882 static int __ipv6_dev_mc_inc(struct net_device *dev,
883 			     const struct in6_addr *addr, unsigned int mode)
884 {
885 	struct ifmcaddr6 *mc;
886 	struct inet6_dev *idev;
887 
888 	ASSERT_RTNL();
889 
890 	/* we need to take a reference on idev */
891 	idev = in6_dev_get(dev);
892 
893 	if (!idev)
894 		return -EINVAL;
895 
896 	write_lock_bh(&idev->lock);
897 	if (idev->dead) {
898 		write_unlock_bh(&idev->lock);
899 		in6_dev_put(idev);
900 		return -ENODEV;
901 	}
902 
903 	for (mc = idev->mc_list; mc; mc = mc->next) {
904 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
905 			mc->mca_users++;
906 			write_unlock_bh(&idev->lock);
907 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
908 			in6_dev_put(idev);
909 			return 0;
910 		}
911 	}
912 
913 	mc = mca_alloc(idev, addr, mode);
914 	if (!mc) {
915 		write_unlock_bh(&idev->lock);
916 		in6_dev_put(idev);
917 		return -ENOMEM;
918 	}
919 
920 	mc->next = idev->mc_list;
921 	idev->mc_list = mc;
922 
923 	/* Hold this for the code below before we unlock,
924 	 * it is already exposed via idev->mc_list.
925 	 */
926 	mca_get(mc);
927 	write_unlock_bh(&idev->lock);
928 
929 	mld_del_delrec(idev, mc);
930 	igmp6_group_added(mc);
931 	ma_put(mc);
932 	return 0;
933 }
934 
935 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
936 {
937 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
938 }
939 EXPORT_SYMBOL(ipv6_dev_mc_inc);
940 
941 /*
942  *	device multicast group del
943  */
944 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
945 {
946 	struct ifmcaddr6 *ma, **map;
947 
948 	ASSERT_RTNL();
949 
950 	write_lock_bh(&idev->lock);
951 	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
952 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
953 			if (--ma->mca_users == 0) {
954 				*map = ma->next;
955 				write_unlock_bh(&idev->lock);
956 
957 				igmp6_group_dropped(ma);
958 				ip6_mc_clear_src(ma);
959 
960 				ma_put(ma);
961 				return 0;
962 			}
963 			write_unlock_bh(&idev->lock);
964 			return 0;
965 		}
966 	}
967 	write_unlock_bh(&idev->lock);
968 
969 	return -ENOENT;
970 }
971 
972 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
973 {
974 	struct inet6_dev *idev;
975 	int err;
976 
977 	ASSERT_RTNL();
978 
979 	idev = __in6_dev_get(dev);
980 	if (!idev)
981 		err = -ENODEV;
982 	else
983 		err = __ipv6_dev_mc_dec(idev, addr);
984 
985 	return err;
986 }
987 EXPORT_SYMBOL(ipv6_dev_mc_dec);
988 
989 /*
990  *	check if the interface/address pair is valid
991  */
992 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
993 			 const struct in6_addr *src_addr)
994 {
995 	struct inet6_dev *idev;
996 	struct ifmcaddr6 *mc;
997 	bool rv = false;
998 
999 	rcu_read_lock();
1000 	idev = __in6_dev_get(dev);
1001 	if (idev) {
1002 		read_lock_bh(&idev->lock);
1003 		for (mc = idev->mc_list; mc; mc = mc->next) {
1004 			if (ipv6_addr_equal(&mc->mca_addr, group))
1005 				break;
1006 		}
1007 		if (mc) {
1008 			if (src_addr && !ipv6_addr_any(src_addr)) {
1009 				struct ip6_sf_list *psf;
1010 
1011 				spin_lock_bh(&mc->mca_lock);
1012 				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
1013 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1014 						break;
1015 				}
1016 				if (psf)
1017 					rv = psf->sf_count[MCAST_INCLUDE] ||
1018 						psf->sf_count[MCAST_EXCLUDE] !=
1019 						mc->mca_sfcount[MCAST_EXCLUDE];
1020 				else
1021 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
1022 				spin_unlock_bh(&mc->mca_lock);
1023 			} else
1024 				rv = true; /* don't filter unspecified source */
1025 		}
1026 		read_unlock_bh(&idev->lock);
1027 	}
1028 	rcu_read_unlock();
1029 	return rv;
1030 }
1031 
1032 static void mld_gq_start_timer(struct inet6_dev *idev)
1033 {
1034 	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
1035 
1036 	idev->mc_gq_running = 1;
1037 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
1038 		in6_dev_hold(idev);
1039 }
1040 
1041 static void mld_gq_stop_timer(struct inet6_dev *idev)
1042 {
1043 	idev->mc_gq_running = 0;
1044 	if (del_timer(&idev->mc_gq_timer))
1045 		__in6_dev_put(idev);
1046 }
1047 
1048 static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
1049 {
1050 	unsigned long tv = prandom_u32() % delay;
1051 
1052 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
1053 		in6_dev_hold(idev);
1054 }
1055 
1056 static void mld_ifc_stop_timer(struct inet6_dev *idev)
1057 {
1058 	idev->mc_ifc_count = 0;
1059 	if (del_timer(&idev->mc_ifc_timer))
1060 		__in6_dev_put(idev);
1061 }
1062 
1063 static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
1064 {
1065 	unsigned long tv = prandom_u32() % delay;
1066 
1067 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1068 		in6_dev_hold(idev);
1069 }
1070 
1071 static void mld_dad_stop_timer(struct inet6_dev *idev)
1072 {
1073 	if (del_timer(&idev->mc_dad_timer))
1074 		__in6_dev_put(idev);
1075 }
1076 
1077 /*
1078  *	IGMP handling (alias multicast ICMPv6 messages)
1079  */
1080 
1081 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1082 {
1083 	unsigned long delay = resptime;
1084 
1085 	/* Do not start timer for these addresses */
1086 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1087 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1088 		return;
1089 
1090 	if (del_timer(&ma->mca_timer)) {
1091 		refcount_dec(&ma->mca_refcnt);
1092 		delay = ma->mca_timer.expires - jiffies;
1093 	}
1094 
1095 	if (delay >= resptime)
1096 		delay = prandom_u32() % resptime;
1097 
1098 	ma->mca_timer.expires = jiffies + delay;
1099 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1100 		refcount_inc(&ma->mca_refcnt);
1101 	ma->mca_flags |= MAF_TIMER_RUNNING;
1102 }
1103 
1104 /* mark EXCLUDE-mode sources */
1105 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1106 			     const struct in6_addr *srcs)
1107 {
1108 	struct ip6_sf_list *psf;
1109 	int i, scount;
1110 
1111 	scount = 0;
1112 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1113 		if (scount == nsrcs)
1114 			break;
1115 		for (i = 0; i < nsrcs; i++) {
1116 			/* skip inactive filters */
1117 			if (psf->sf_count[MCAST_INCLUDE] ||
1118 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1119 			    psf->sf_count[MCAST_EXCLUDE])
1120 				break;
1121 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1122 				scount++;
1123 				break;
1124 			}
1125 		}
1126 	}
1127 	pmc->mca_flags &= ~MAF_GSQUERY;
1128 	if (scount == nsrcs)	/* all sources excluded */
1129 		return false;
1130 	return true;
1131 }
1132 
1133 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1134 			    const struct in6_addr *srcs)
1135 {
1136 	struct ip6_sf_list *psf;
1137 	int i, scount;
1138 
1139 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1140 		return mld_xmarksources(pmc, nsrcs, srcs);
1141 
1142 	/* mark INCLUDE-mode sources */
1143 
1144 	scount = 0;
1145 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1146 		if (scount == nsrcs)
1147 			break;
1148 		for (i = 0; i < nsrcs; i++) {
1149 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1150 				psf->sf_gsresp = 1;
1151 				scount++;
1152 				break;
1153 			}
1154 		}
1155 	}
1156 	if (!scount) {
1157 		pmc->mca_flags &= ~MAF_GSQUERY;
1158 		return false;
1159 	}
1160 	pmc->mca_flags |= MAF_GSQUERY;
1161 	return true;
1162 }
1163 
1164 static int mld_force_mld_version(const struct inet6_dev *idev)
1165 {
1166 	/* Normally, both are 0 here. If enforcement to a particular is
1167 	 * being used, individual device enforcement will have a lower
1168 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1169 	 */
1170 
1171 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1172 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1173 	else
1174 		return idev->cnf.force_mld_version;
1175 }
1176 
1177 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1178 {
1179 	return mld_force_mld_version(idev) == 2;
1180 }
1181 
1182 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1183 {
1184 	return mld_force_mld_version(idev) == 1;
1185 }
1186 
1187 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1188 {
1189 	if (mld_in_v2_mode_only(idev))
1190 		return false;
1191 	if (mld_in_v1_mode_only(idev))
1192 		return true;
1193 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1194 		return true;
1195 
1196 	return false;
1197 }
1198 
1199 static void mld_set_v1_mode(struct inet6_dev *idev)
1200 {
1201 	/* RFC3810, relevant sections:
1202 	 *  - 9.1. Robustness Variable
1203 	 *  - 9.2. Query Interval
1204 	 *  - 9.3. Query Response Interval
1205 	 *  - 9.12. Older Version Querier Present Timeout
1206 	 */
1207 	unsigned long switchback;
1208 
1209 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1210 
1211 	idev->mc_v1_seen = jiffies + switchback;
1212 }
1213 
1214 static void mld_update_qrv(struct inet6_dev *idev,
1215 			   const struct mld2_query *mlh2)
1216 {
1217 	/* RFC3810, relevant sections:
1218 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1219 	 *  - 9.1. Robustness Variable
1220 	 */
1221 
1222 	/* The value of the Robustness Variable MUST NOT be zero,
1223 	 * and SHOULD NOT be one. Catch this here if we ever run
1224 	 * into such a case in future.
1225 	 */
1226 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1227 	WARN_ON(idev->mc_qrv == 0);
1228 
1229 	if (mlh2->mld2q_qrv > 0)
1230 		idev->mc_qrv = mlh2->mld2q_qrv;
1231 
1232 	if (unlikely(idev->mc_qrv < min_qrv)) {
1233 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1234 				     idev->mc_qrv, min_qrv);
1235 		idev->mc_qrv = min_qrv;
1236 	}
1237 }
1238 
1239 static void mld_update_qi(struct inet6_dev *idev,
1240 			  const struct mld2_query *mlh2)
1241 {
1242 	/* RFC3810, relevant sections:
1243 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1244 	 *  - 9.2. Query Interval
1245 	 *  - 9.12. Older Version Querier Present Timeout
1246 	 *    (the [Query Interval] in the last Query received)
1247 	 */
1248 	unsigned long mc_qqi;
1249 
1250 	if (mlh2->mld2q_qqic < 128) {
1251 		mc_qqi = mlh2->mld2q_qqic;
1252 	} else {
1253 		unsigned long mc_man, mc_exp;
1254 
1255 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1256 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1257 
1258 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1259 	}
1260 
1261 	idev->mc_qi = mc_qqi * HZ;
1262 }
1263 
1264 static void mld_update_qri(struct inet6_dev *idev,
1265 			   const struct mld2_query *mlh2)
1266 {
1267 	/* RFC3810, relevant sections:
1268 	 *  - 5.1.3. Maximum Response Code
1269 	 *  - 9.3. Query Response Interval
1270 	 */
1271 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1272 }
1273 
1274 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1275 			  unsigned long *max_delay, bool v1_query)
1276 {
1277 	unsigned long mldv1_md;
1278 
1279 	/* Ignore v1 queries */
1280 	if (mld_in_v2_mode_only(idev))
1281 		return -EINVAL;
1282 
1283 	mldv1_md = ntohs(mld->mld_maxdelay);
1284 
1285 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1286 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1287 	 * only works when the exponential algorithm is not being
1288 	 * used (as MLDv1 is unaware of such things).
1289 	 *
1290 	 * According to the RFC author, the MLDv2 implementations
1291 	 * he's aware of all use a MRC < 32768 on start up queries.
1292 	 *
1293 	 * Thus, should we *ever* encounter something else larger
1294 	 * than that, just assume the maximum possible within our
1295 	 * reach.
1296 	 */
1297 	if (!v1_query)
1298 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1299 
1300 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1301 
1302 	/* MLDv1 router present: we need to go into v1 mode *only*
1303 	 * when an MLDv1 query is received as per section 9.12. of
1304 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1305 	 * queries MUST be of exactly 24 octets.
1306 	 */
1307 	if (v1_query)
1308 		mld_set_v1_mode(idev);
1309 
1310 	/* cancel MLDv2 report timer */
1311 	mld_gq_stop_timer(idev);
1312 	/* cancel the interface change timer */
1313 	mld_ifc_stop_timer(idev);
1314 	/* clear deleted report items */
1315 	mld_clear_delrec(idev);
1316 
1317 	return 0;
1318 }
1319 
1320 static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1321 			  unsigned long *max_delay)
1322 {
1323 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1324 
1325 	mld_update_qrv(idev, mld);
1326 	mld_update_qi(idev, mld);
1327 	mld_update_qri(idev, mld);
1328 
1329 	idev->mc_maxdelay = *max_delay;
1330 
1331 	return 0;
1332 }
1333 
1334 /* called with rcu_read_lock() */
1335 int igmp6_event_query(struct sk_buff *skb)
1336 {
1337 	struct mld2_query *mlh2 = NULL;
1338 	struct ifmcaddr6 *ma;
1339 	const struct in6_addr *group;
1340 	unsigned long max_delay;
1341 	struct inet6_dev *idev;
1342 	struct mld_msg *mld;
1343 	int group_type;
1344 	int mark = 0;
1345 	int len, err;
1346 
1347 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1348 		return -EINVAL;
1349 
1350 	/* compute payload length excluding extension headers */
1351 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1352 	len -= skb_network_header_len(skb);
1353 
1354 	/* RFC3810 6.2
1355 	 * Upon reception of an MLD message that contains a Query, the node
1356 	 * checks if the source address of the message is a valid link-local
1357 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1358 	 * option is present in the Hop-By-Hop Options header of the IPv6
1359 	 * packet.  If any of these checks fails, the packet is dropped.
1360 	 */
1361 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1362 	    ipv6_hdr(skb)->hop_limit != 1 ||
1363 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1364 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1365 		return -EINVAL;
1366 
1367 	idev = __in6_dev_get(skb->dev);
1368 	if (!idev)
1369 		return 0;
1370 
1371 	mld = (struct mld_msg *)icmp6_hdr(skb);
1372 	group = &mld->mld_mca;
1373 	group_type = ipv6_addr_type(group);
1374 
1375 	if (group_type != IPV6_ADDR_ANY &&
1376 	    !(group_type&IPV6_ADDR_MULTICAST))
1377 		return -EINVAL;
1378 
1379 	if (len < MLD_V1_QUERY_LEN) {
1380 		return -EINVAL;
1381 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1382 		err = mld_process_v1(idev, mld, &max_delay,
1383 				     len == MLD_V1_QUERY_LEN);
1384 		if (err < 0)
1385 			return err;
1386 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1387 		int srcs_offset = sizeof(struct mld2_query) -
1388 				  sizeof(struct icmp6hdr);
1389 
1390 		if (!pskb_may_pull(skb, srcs_offset))
1391 			return -EINVAL;
1392 
1393 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1394 
1395 		err = mld_process_v2(idev, mlh2, &max_delay);
1396 		if (err < 0)
1397 			return err;
1398 
1399 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1400 			if (mlh2->mld2q_nsrcs)
1401 				return -EINVAL; /* no sources allowed */
1402 
1403 			mld_gq_start_timer(idev);
1404 			return 0;
1405 		}
1406 		/* mark sources to include, if group & source-specific */
1407 		if (mlh2->mld2q_nsrcs != 0) {
1408 			if (!pskb_may_pull(skb, srcs_offset +
1409 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1410 				return -EINVAL;
1411 
1412 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1413 			mark = 1;
1414 		}
1415 	} else {
1416 		return -EINVAL;
1417 	}
1418 
1419 	read_lock_bh(&idev->lock);
1420 	if (group_type == IPV6_ADDR_ANY) {
1421 		for (ma = idev->mc_list; ma; ma = ma->next) {
1422 			spin_lock_bh(&ma->mca_lock);
1423 			igmp6_group_queried(ma, max_delay);
1424 			spin_unlock_bh(&ma->mca_lock);
1425 		}
1426 	} else {
1427 		for (ma = idev->mc_list; ma; ma = ma->next) {
1428 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1429 				continue;
1430 			spin_lock_bh(&ma->mca_lock);
1431 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1432 				/* gsquery <- gsquery && mark */
1433 				if (!mark)
1434 					ma->mca_flags &= ~MAF_GSQUERY;
1435 			} else {
1436 				/* gsquery <- mark */
1437 				if (mark)
1438 					ma->mca_flags |= MAF_GSQUERY;
1439 				else
1440 					ma->mca_flags &= ~MAF_GSQUERY;
1441 			}
1442 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1443 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1444 				igmp6_group_queried(ma, max_delay);
1445 			spin_unlock_bh(&ma->mca_lock);
1446 			break;
1447 		}
1448 	}
1449 	read_unlock_bh(&idev->lock);
1450 
1451 	return 0;
1452 }
1453 
1454 /* called with rcu_read_lock() */
1455 int igmp6_event_report(struct sk_buff *skb)
1456 {
1457 	struct ifmcaddr6 *ma;
1458 	struct inet6_dev *idev;
1459 	struct mld_msg *mld;
1460 	int addr_type;
1461 
1462 	/* Our own report looped back. Ignore it. */
1463 	if (skb->pkt_type == PACKET_LOOPBACK)
1464 		return 0;
1465 
1466 	/* send our report if the MC router may not have heard this report */
1467 	if (skb->pkt_type != PACKET_MULTICAST &&
1468 	    skb->pkt_type != PACKET_BROADCAST)
1469 		return 0;
1470 
1471 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1472 		return -EINVAL;
1473 
1474 	mld = (struct mld_msg *)icmp6_hdr(skb);
1475 
1476 	/* Drop reports with not link local source */
1477 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1478 	if (addr_type != IPV6_ADDR_ANY &&
1479 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1480 		return -EINVAL;
1481 
1482 	idev = __in6_dev_get(skb->dev);
1483 	if (!idev)
1484 		return -ENODEV;
1485 
1486 	/*
1487 	 *	Cancel the timer for this group
1488 	 */
1489 
1490 	read_lock_bh(&idev->lock);
1491 	for (ma = idev->mc_list; ma; ma = ma->next) {
1492 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1493 			spin_lock(&ma->mca_lock);
1494 			if (del_timer(&ma->mca_timer))
1495 				refcount_dec(&ma->mca_refcnt);
1496 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1497 			spin_unlock(&ma->mca_lock);
1498 			break;
1499 		}
1500 	}
1501 	read_unlock_bh(&idev->lock);
1502 	return 0;
1503 }
1504 
1505 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1506 		  int gdeleted, int sdeleted)
1507 {
1508 	switch (type) {
1509 	case MLD2_MODE_IS_INCLUDE:
1510 	case MLD2_MODE_IS_EXCLUDE:
1511 		if (gdeleted || sdeleted)
1512 			return false;
1513 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1514 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1515 				return true;
1516 			/* don't include if this source is excluded
1517 			 * in all filters
1518 			 */
1519 			if (psf->sf_count[MCAST_INCLUDE])
1520 				return type == MLD2_MODE_IS_INCLUDE;
1521 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1522 				psf->sf_count[MCAST_EXCLUDE];
1523 		}
1524 		return false;
1525 	case MLD2_CHANGE_TO_INCLUDE:
1526 		if (gdeleted || sdeleted)
1527 			return false;
1528 		return psf->sf_count[MCAST_INCLUDE] != 0;
1529 	case MLD2_CHANGE_TO_EXCLUDE:
1530 		if (gdeleted || sdeleted)
1531 			return false;
1532 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1533 		    psf->sf_count[MCAST_INCLUDE])
1534 			return false;
1535 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1536 			psf->sf_count[MCAST_EXCLUDE];
1537 	case MLD2_ALLOW_NEW_SOURCES:
1538 		if (gdeleted || !psf->sf_crcount)
1539 			return false;
1540 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1541 	case MLD2_BLOCK_OLD_SOURCES:
1542 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1543 			return gdeleted || (psf->sf_crcount && sdeleted);
1544 		return psf->sf_crcount && !gdeleted && !sdeleted;
1545 	}
1546 	return false;
1547 }
1548 
1549 static int
1550 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1551 {
1552 	struct ip6_sf_list *psf;
1553 	int scount = 0;
1554 
1555 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1556 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1557 			continue;
1558 		scount++;
1559 	}
1560 	return scount;
1561 }
1562 
1563 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1564 		       struct net_device *dev,
1565 		       const struct in6_addr *saddr,
1566 		       const struct in6_addr *daddr,
1567 		       int proto, int len)
1568 {
1569 	struct ipv6hdr *hdr;
1570 
1571 	skb->protocol = htons(ETH_P_IPV6);
1572 	skb->dev = dev;
1573 
1574 	skb_reset_network_header(skb);
1575 	skb_put(skb, sizeof(struct ipv6hdr));
1576 	hdr = ipv6_hdr(skb);
1577 
1578 	ip6_flow_hdr(hdr, 0, 0);
1579 
1580 	hdr->payload_len = htons(len);
1581 	hdr->nexthdr = proto;
1582 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1583 
1584 	hdr->saddr = *saddr;
1585 	hdr->daddr = *daddr;
1586 }
1587 
1588 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1589 {
1590 	struct net_device *dev = idev->dev;
1591 	struct net *net = dev_net(dev);
1592 	struct sock *sk = net->ipv6.igmp_sk;
1593 	struct sk_buff *skb;
1594 	struct mld2_report *pmr;
1595 	struct in6_addr addr_buf;
1596 	const struct in6_addr *saddr;
1597 	int hlen = LL_RESERVED_SPACE(dev);
1598 	int tlen = dev->needed_tailroom;
1599 	unsigned int size = mtu + hlen + tlen;
1600 	int err;
1601 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1602 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1603 		     IPV6_TLV_PADN, 0 };
1604 
1605 	/* we assume size > sizeof(ra) here */
1606 	/* limit our allocations to order-0 page */
1607 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1608 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1609 
1610 	if (!skb)
1611 		return NULL;
1612 
1613 	skb->priority = TC_PRIO_CONTROL;
1614 	skb_reserve(skb, hlen);
1615 	skb_tailroom_reserve(skb, mtu, tlen);
1616 
1617 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1618 		/* <draft-ietf-magma-mld-source-05.txt>:
1619 		 * use unspecified address as the source address
1620 		 * when a valid link-local address is not available.
1621 		 */
1622 		saddr = &in6addr_any;
1623 	} else
1624 		saddr = &addr_buf;
1625 
1626 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1627 
1628 	skb_put_data(skb, ra, sizeof(ra));
1629 
1630 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1631 	skb_put(skb, sizeof(*pmr));
1632 	pmr = (struct mld2_report *)skb_transport_header(skb);
1633 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1634 	pmr->mld2r_resv1 = 0;
1635 	pmr->mld2r_cksum = 0;
1636 	pmr->mld2r_resv2 = 0;
1637 	pmr->mld2r_ngrec = 0;
1638 	return skb;
1639 }
1640 
1641 static void mld_sendpack(struct sk_buff *skb)
1642 {
1643 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1644 	struct mld2_report *pmr =
1645 			      (struct mld2_report *)skb_transport_header(skb);
1646 	int payload_len, mldlen;
1647 	struct inet6_dev *idev;
1648 	struct net *net = dev_net(skb->dev);
1649 	int err;
1650 	struct flowi6 fl6;
1651 	struct dst_entry *dst;
1652 
1653 	rcu_read_lock();
1654 	idev = __in6_dev_get(skb->dev);
1655 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1656 
1657 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1658 		sizeof(*pip6);
1659 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1660 	pip6->payload_len = htons(payload_len);
1661 
1662 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1663 					   IPPROTO_ICMPV6,
1664 					   csum_partial(skb_transport_header(skb),
1665 							mldlen, 0));
1666 
1667 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1668 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1669 			 skb->dev->ifindex);
1670 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1671 
1672 	err = 0;
1673 	if (IS_ERR(dst)) {
1674 		err = PTR_ERR(dst);
1675 		dst = NULL;
1676 	}
1677 	skb_dst_set(skb, dst);
1678 	if (err)
1679 		goto err_out;
1680 
1681 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1682 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1683 		      dst_output);
1684 out:
1685 	if (!err) {
1686 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1687 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1688 	} else {
1689 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1690 	}
1691 
1692 	rcu_read_unlock();
1693 	return;
1694 
1695 err_out:
1696 	kfree_skb(skb);
1697 	goto out;
1698 }
1699 
1700 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1701 {
1702 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1703 }
1704 
1705 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1706 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1707 {
1708 	struct mld2_report *pmr;
1709 	struct mld2_grec *pgr;
1710 
1711 	if (!skb) {
1712 		skb = mld_newpack(pmc->idev, mtu);
1713 		if (!skb)
1714 			return NULL;
1715 	}
1716 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1717 	pgr->grec_type = type;
1718 	pgr->grec_auxwords = 0;
1719 	pgr->grec_nsrcs = 0;
1720 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1721 	pmr = (struct mld2_report *)skb_transport_header(skb);
1722 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1723 	*ppgr = pgr;
1724 	return skb;
1725 }
1726 
1727 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1728 
1729 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1730 	int type, int gdeleted, int sdeleted, int crsend)
1731 {
1732 	struct inet6_dev *idev = pmc->idev;
1733 	struct net_device *dev = idev->dev;
1734 	struct mld2_report *pmr;
1735 	struct mld2_grec *pgr = NULL;
1736 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1737 	int scount, stotal, first, isquery, truncate;
1738 	unsigned int mtu;
1739 
1740 	if (pmc->mca_flags & MAF_NOREPORT)
1741 		return skb;
1742 
1743 	mtu = READ_ONCE(dev->mtu);
1744 	if (mtu < IPV6_MIN_MTU)
1745 		return skb;
1746 
1747 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1748 		  type == MLD2_MODE_IS_EXCLUDE;
1749 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1750 		    type == MLD2_CHANGE_TO_EXCLUDE;
1751 
1752 	stotal = scount = 0;
1753 
1754 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1755 
1756 	if (!*psf_list)
1757 		goto empty_source;
1758 
1759 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1760 
1761 	/* EX and TO_EX get a fresh packet, if needed */
1762 	if (truncate) {
1763 		if (pmr && pmr->mld2r_ngrec &&
1764 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1765 			if (skb)
1766 				mld_sendpack(skb);
1767 			skb = mld_newpack(idev, mtu);
1768 		}
1769 	}
1770 	first = 1;
1771 	psf_prev = NULL;
1772 	for (psf = *psf_list; psf; psf = psf_next) {
1773 		struct in6_addr *psrc;
1774 
1775 		psf_next = psf->sf_next;
1776 
1777 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1778 			psf_prev = psf;
1779 			continue;
1780 		}
1781 
1782 		/* Based on RFC3810 6.1. Should not send source-list change
1783 		 * records when there is a filter mode change.
1784 		 */
1785 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1786 		     (!gdeleted && pmc->mca_crcount)) &&
1787 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1788 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1789 			goto decrease_sf_crcount;
1790 
1791 		/* clear marks on query responses */
1792 		if (isquery)
1793 			psf->sf_gsresp = 0;
1794 
1795 		if (AVAILABLE(skb) < sizeof(*psrc) +
1796 		    first*sizeof(struct mld2_grec)) {
1797 			if (truncate && !first)
1798 				break;	 /* truncate these */
1799 			if (pgr)
1800 				pgr->grec_nsrcs = htons(scount);
1801 			if (skb)
1802 				mld_sendpack(skb);
1803 			skb = mld_newpack(idev, mtu);
1804 			first = 1;
1805 			scount = 0;
1806 		}
1807 		if (first) {
1808 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1809 			first = 0;
1810 		}
1811 		if (!skb)
1812 			return NULL;
1813 		psrc = skb_put(skb, sizeof(*psrc));
1814 		*psrc = psf->sf_addr;
1815 		scount++; stotal++;
1816 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1817 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1818 decrease_sf_crcount:
1819 			psf->sf_crcount--;
1820 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1821 				if (psf_prev)
1822 					psf_prev->sf_next = psf->sf_next;
1823 				else
1824 					*psf_list = psf->sf_next;
1825 				kfree(psf);
1826 				continue;
1827 			}
1828 		}
1829 		psf_prev = psf;
1830 	}
1831 
1832 empty_source:
1833 	if (!stotal) {
1834 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1835 		    type == MLD2_BLOCK_OLD_SOURCES)
1836 			return skb;
1837 		if (pmc->mca_crcount || isquery || crsend) {
1838 			/* make sure we have room for group header */
1839 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1840 				mld_sendpack(skb);
1841 				skb = NULL; /* add_grhead will get a new one */
1842 			}
1843 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1844 		}
1845 	}
1846 	if (pgr)
1847 		pgr->grec_nsrcs = htons(scount);
1848 
1849 	if (isquery)
1850 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1851 	return skb;
1852 }
1853 
1854 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1855 {
1856 	struct sk_buff *skb = NULL;
1857 	int type;
1858 
1859 	read_lock_bh(&idev->lock);
1860 	if (!pmc) {
1861 		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1862 			if (pmc->mca_flags & MAF_NOREPORT)
1863 				continue;
1864 			spin_lock_bh(&pmc->mca_lock);
1865 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1866 				type = MLD2_MODE_IS_EXCLUDE;
1867 			else
1868 				type = MLD2_MODE_IS_INCLUDE;
1869 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1870 			spin_unlock_bh(&pmc->mca_lock);
1871 		}
1872 	} else {
1873 		spin_lock_bh(&pmc->mca_lock);
1874 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1875 			type = MLD2_MODE_IS_EXCLUDE;
1876 		else
1877 			type = MLD2_MODE_IS_INCLUDE;
1878 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1879 		spin_unlock_bh(&pmc->mca_lock);
1880 	}
1881 	read_unlock_bh(&idev->lock);
1882 	if (skb)
1883 		mld_sendpack(skb);
1884 }
1885 
1886 /*
1887  * remove zero-count source records from a source filter list
1888  */
1889 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1890 {
1891 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1892 
1893 	psf_prev = NULL;
1894 	for (psf = *ppsf; psf; psf = psf_next) {
1895 		psf_next = psf->sf_next;
1896 		if (psf->sf_crcount == 0) {
1897 			if (psf_prev)
1898 				psf_prev->sf_next = psf->sf_next;
1899 			else
1900 				*ppsf = psf->sf_next;
1901 			kfree(psf);
1902 		} else
1903 			psf_prev = psf;
1904 	}
1905 }
1906 
1907 static void mld_send_cr(struct inet6_dev *idev)
1908 {
1909 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1910 	struct sk_buff *skb = NULL;
1911 	int type, dtype;
1912 
1913 	read_lock_bh(&idev->lock);
1914 	spin_lock(&idev->mc_lock);
1915 
1916 	/* deleted MCA's */
1917 	pmc_prev = NULL;
1918 	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
1919 		pmc_next = pmc->next;
1920 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1921 			type = MLD2_BLOCK_OLD_SOURCES;
1922 			dtype = MLD2_BLOCK_OLD_SOURCES;
1923 			skb = add_grec(skb, pmc, type, 1, 0, 0);
1924 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
1925 		}
1926 		if (pmc->mca_crcount) {
1927 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1928 				type = MLD2_CHANGE_TO_INCLUDE;
1929 				skb = add_grec(skb, pmc, type, 1, 0, 0);
1930 			}
1931 			pmc->mca_crcount--;
1932 			if (pmc->mca_crcount == 0) {
1933 				mld_clear_zeros(&pmc->mca_tomb);
1934 				mld_clear_zeros(&pmc->mca_sources);
1935 			}
1936 		}
1937 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1938 		    !pmc->mca_sources) {
1939 			if (pmc_prev)
1940 				pmc_prev->next = pmc_next;
1941 			else
1942 				idev->mc_tomb = pmc_next;
1943 			in6_dev_put(pmc->idev);
1944 			kfree(pmc);
1945 		} else
1946 			pmc_prev = pmc;
1947 	}
1948 	spin_unlock(&idev->mc_lock);
1949 
1950 	/* change recs */
1951 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1952 		spin_lock_bh(&pmc->mca_lock);
1953 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1954 			type = MLD2_BLOCK_OLD_SOURCES;
1955 			dtype = MLD2_ALLOW_NEW_SOURCES;
1956 		} else {
1957 			type = MLD2_ALLOW_NEW_SOURCES;
1958 			dtype = MLD2_BLOCK_OLD_SOURCES;
1959 		}
1960 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1961 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
1962 
1963 		/* filter mode changes */
1964 		if (pmc->mca_crcount) {
1965 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1966 				type = MLD2_CHANGE_TO_EXCLUDE;
1967 			else
1968 				type = MLD2_CHANGE_TO_INCLUDE;
1969 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1970 			pmc->mca_crcount--;
1971 		}
1972 		spin_unlock_bh(&pmc->mca_lock);
1973 	}
1974 	read_unlock_bh(&idev->lock);
1975 	if (!skb)
1976 		return;
1977 	(void) mld_sendpack(skb);
1978 }
1979 
1980 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1981 {
1982 	struct net *net = dev_net(dev);
1983 	struct sock *sk = net->ipv6.igmp_sk;
1984 	struct inet6_dev *idev;
1985 	struct sk_buff *skb;
1986 	struct mld_msg *hdr;
1987 	const struct in6_addr *snd_addr, *saddr;
1988 	struct in6_addr addr_buf;
1989 	int hlen = LL_RESERVED_SPACE(dev);
1990 	int tlen = dev->needed_tailroom;
1991 	int err, len, payload_len, full_len;
1992 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1993 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1994 		     IPV6_TLV_PADN, 0 };
1995 	struct flowi6 fl6;
1996 	struct dst_entry *dst;
1997 
1998 	if (type == ICMPV6_MGM_REDUCTION)
1999 		snd_addr = &in6addr_linklocal_allrouters;
2000 	else
2001 		snd_addr = addr;
2002 
2003 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2004 	payload_len = len + sizeof(ra);
2005 	full_len = sizeof(struct ipv6hdr) + payload_len;
2006 
2007 	rcu_read_lock();
2008 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
2009 		      IPSTATS_MIB_OUT, full_len);
2010 	rcu_read_unlock();
2011 
2012 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
2013 
2014 	if (!skb) {
2015 		rcu_read_lock();
2016 		IP6_INC_STATS(net, __in6_dev_get(dev),
2017 			      IPSTATS_MIB_OUTDISCARDS);
2018 		rcu_read_unlock();
2019 		return;
2020 	}
2021 	skb->priority = TC_PRIO_CONTROL;
2022 	skb_reserve(skb, hlen);
2023 
2024 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2025 		/* <draft-ietf-magma-mld-source-05.txt>:
2026 		 * use unspecified address as the source address
2027 		 * when a valid link-local address is not available.
2028 		 */
2029 		saddr = &in6addr_any;
2030 	} else
2031 		saddr = &addr_buf;
2032 
2033 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2034 
2035 	skb_put_data(skb, ra, sizeof(ra));
2036 
2037 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2038 	hdr->mld_type = type;
2039 	hdr->mld_mca = *addr;
2040 
2041 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2042 					 IPPROTO_ICMPV6,
2043 					 csum_partial(hdr, len, 0));
2044 
2045 	rcu_read_lock();
2046 	idev = __in6_dev_get(skb->dev);
2047 
2048 	icmpv6_flow_init(sk, &fl6, type,
2049 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2050 			 skb->dev->ifindex);
2051 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2052 	if (IS_ERR(dst)) {
2053 		err = PTR_ERR(dst);
2054 		goto err_out;
2055 	}
2056 
2057 	skb_dst_set(skb, dst);
2058 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2059 		      net, sk, skb, NULL, skb->dev,
2060 		      dst_output);
2061 out:
2062 	if (!err) {
2063 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2064 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2065 	} else
2066 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2067 
2068 	rcu_read_unlock();
2069 	return;
2070 
2071 err_out:
2072 	kfree_skb(skb);
2073 	goto out;
2074 }
2075 
2076 static void mld_send_initial_cr(struct inet6_dev *idev)
2077 {
2078 	struct sk_buff *skb;
2079 	struct ifmcaddr6 *pmc;
2080 	int type;
2081 
2082 	if (mld_in_v1_mode(idev))
2083 		return;
2084 
2085 	skb = NULL;
2086 	read_lock_bh(&idev->lock);
2087 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2088 		spin_lock_bh(&pmc->mca_lock);
2089 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2090 			type = MLD2_CHANGE_TO_EXCLUDE;
2091 		else
2092 			type = MLD2_ALLOW_NEW_SOURCES;
2093 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2094 		spin_unlock_bh(&pmc->mca_lock);
2095 	}
2096 	read_unlock_bh(&idev->lock);
2097 	if (skb)
2098 		mld_sendpack(skb);
2099 }
2100 
2101 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2102 {
2103 	idev->mc_dad_count = idev->mc_qrv;
2104 	if (idev->mc_dad_count) {
2105 		mld_send_initial_cr(idev);
2106 		idev->mc_dad_count--;
2107 		if (idev->mc_dad_count)
2108 			mld_dad_start_timer(idev,
2109 					    unsolicited_report_interval(idev));
2110 	}
2111 }
2112 
2113 static void mld_dad_timer_expire(struct timer_list *t)
2114 {
2115 	struct inet6_dev *idev = from_timer(idev, t, mc_dad_timer);
2116 
2117 	mld_send_initial_cr(idev);
2118 	if (idev->mc_dad_count) {
2119 		idev->mc_dad_count--;
2120 		if (idev->mc_dad_count)
2121 			mld_dad_start_timer(idev,
2122 					    unsolicited_report_interval(idev));
2123 	}
2124 	in6_dev_put(idev);
2125 }
2126 
2127 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2128 	const struct in6_addr *psfsrc)
2129 {
2130 	struct ip6_sf_list *psf, *psf_prev;
2131 	int rv = 0;
2132 
2133 	psf_prev = NULL;
2134 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2135 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2136 			break;
2137 		psf_prev = psf;
2138 	}
2139 	if (!psf || psf->sf_count[sfmode] == 0) {
2140 		/* source filter not found, or count wrong =>  bug */
2141 		return -ESRCH;
2142 	}
2143 	psf->sf_count[sfmode]--;
2144 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2145 		struct inet6_dev *idev = pmc->idev;
2146 
2147 		/* no more filters for this source */
2148 		if (psf_prev)
2149 			psf_prev->sf_next = psf->sf_next;
2150 		else
2151 			pmc->mca_sources = psf->sf_next;
2152 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2153 		    !mld_in_v1_mode(idev)) {
2154 			psf->sf_crcount = idev->mc_qrv;
2155 			psf->sf_next = pmc->mca_tomb;
2156 			pmc->mca_tomb = psf;
2157 			rv = 1;
2158 		} else
2159 			kfree(psf);
2160 	}
2161 	return rv;
2162 }
2163 
2164 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2165 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2166 			  int delta)
2167 {
2168 	struct ifmcaddr6 *pmc;
2169 	int	changerec = 0;
2170 	int	i, err;
2171 
2172 	if (!idev)
2173 		return -ENODEV;
2174 	read_lock_bh(&idev->lock);
2175 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2176 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2177 			break;
2178 	}
2179 	if (!pmc) {
2180 		/* MCA not found?? bug */
2181 		read_unlock_bh(&idev->lock);
2182 		return -ESRCH;
2183 	}
2184 	spin_lock_bh(&pmc->mca_lock);
2185 	sf_markstate(pmc);
2186 	if (!delta) {
2187 		if (!pmc->mca_sfcount[sfmode]) {
2188 			spin_unlock_bh(&pmc->mca_lock);
2189 			read_unlock_bh(&idev->lock);
2190 			return -EINVAL;
2191 		}
2192 		pmc->mca_sfcount[sfmode]--;
2193 	}
2194 	err = 0;
2195 	for (i = 0; i < sfcount; i++) {
2196 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2197 
2198 		changerec |= rv > 0;
2199 		if (!err && rv < 0)
2200 			err = rv;
2201 	}
2202 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2203 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2204 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2205 		struct ip6_sf_list *psf;
2206 
2207 		/* filter mode change */
2208 		pmc->mca_sfmode = MCAST_INCLUDE;
2209 		pmc->mca_crcount = idev->mc_qrv;
2210 		idev->mc_ifc_count = pmc->mca_crcount;
2211 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2212 			psf->sf_crcount = 0;
2213 		mld_ifc_event(pmc->idev);
2214 	} else if (sf_setstate(pmc) || changerec)
2215 		mld_ifc_event(pmc->idev);
2216 	spin_unlock_bh(&pmc->mca_lock);
2217 	read_unlock_bh(&idev->lock);
2218 	return err;
2219 }
2220 
2221 /*
2222  * Add multicast single-source filter to the interface list
2223  */
2224 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2225 	const struct in6_addr *psfsrc)
2226 {
2227 	struct ip6_sf_list *psf, *psf_prev;
2228 
2229 	psf_prev = NULL;
2230 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2231 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2232 			break;
2233 		psf_prev = psf;
2234 	}
2235 	if (!psf) {
2236 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2237 		if (!psf)
2238 			return -ENOBUFS;
2239 
2240 		psf->sf_addr = *psfsrc;
2241 		if (psf_prev) {
2242 			psf_prev->sf_next = psf;
2243 		} else
2244 			pmc->mca_sources = psf;
2245 	}
2246 	psf->sf_count[sfmode]++;
2247 	return 0;
2248 }
2249 
2250 static void sf_markstate(struct ifmcaddr6 *pmc)
2251 {
2252 	struct ip6_sf_list *psf;
2253 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2254 
2255 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2256 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2257 			psf->sf_oldin = mca_xcount ==
2258 				psf->sf_count[MCAST_EXCLUDE] &&
2259 				!psf->sf_count[MCAST_INCLUDE];
2260 		} else
2261 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2262 }
2263 
2264 static int sf_setstate(struct ifmcaddr6 *pmc)
2265 {
2266 	struct ip6_sf_list *psf, *dpsf;
2267 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2268 	int qrv = pmc->idev->mc_qrv;
2269 	int new_in, rv;
2270 
2271 	rv = 0;
2272 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2273 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2274 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2275 				!psf->sf_count[MCAST_INCLUDE];
2276 		} else
2277 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2278 		if (new_in) {
2279 			if (!psf->sf_oldin) {
2280 				struct ip6_sf_list *prev = NULL;
2281 
2282 				for (dpsf = pmc->mca_tomb; dpsf;
2283 				     dpsf = dpsf->sf_next) {
2284 					if (ipv6_addr_equal(&dpsf->sf_addr,
2285 					    &psf->sf_addr))
2286 						break;
2287 					prev = dpsf;
2288 				}
2289 				if (dpsf) {
2290 					if (prev)
2291 						prev->sf_next = dpsf->sf_next;
2292 					else
2293 						pmc->mca_tomb = dpsf->sf_next;
2294 					kfree(dpsf);
2295 				}
2296 				psf->sf_crcount = qrv;
2297 				rv++;
2298 			}
2299 		} else if (psf->sf_oldin) {
2300 			psf->sf_crcount = 0;
2301 			/*
2302 			 * add or update "delete" records if an active filter
2303 			 * is now inactive
2304 			 */
2305 			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
2306 				if (ipv6_addr_equal(&dpsf->sf_addr,
2307 				    &psf->sf_addr))
2308 					break;
2309 			if (!dpsf) {
2310 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2311 				if (!dpsf)
2312 					continue;
2313 				*dpsf = *psf;
2314 				/* pmc->mca_lock held by callers */
2315 				dpsf->sf_next = pmc->mca_tomb;
2316 				pmc->mca_tomb = dpsf;
2317 			}
2318 			dpsf->sf_crcount = qrv;
2319 			rv++;
2320 		}
2321 	}
2322 	return rv;
2323 }
2324 
2325 /*
2326  * Add multicast source filter list to the interface list
2327  */
2328 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2329 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2330 			  int delta)
2331 {
2332 	struct ifmcaddr6 *pmc;
2333 	int	isexclude;
2334 	int	i, err;
2335 
2336 	if (!idev)
2337 		return -ENODEV;
2338 	read_lock_bh(&idev->lock);
2339 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2340 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2341 			break;
2342 	}
2343 	if (!pmc) {
2344 		/* MCA not found?? bug */
2345 		read_unlock_bh(&idev->lock);
2346 		return -ESRCH;
2347 	}
2348 	spin_lock_bh(&pmc->mca_lock);
2349 
2350 	sf_markstate(pmc);
2351 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2352 	if (!delta)
2353 		pmc->mca_sfcount[sfmode]++;
2354 	err = 0;
2355 	for (i = 0; i < sfcount; i++) {
2356 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2357 		if (err)
2358 			break;
2359 	}
2360 	if (err) {
2361 		int j;
2362 
2363 		if (!delta)
2364 			pmc->mca_sfcount[sfmode]--;
2365 		for (j = 0; j < i; j++)
2366 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2367 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2368 		struct ip6_sf_list *psf;
2369 
2370 		/* filter mode change */
2371 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2372 			pmc->mca_sfmode = MCAST_EXCLUDE;
2373 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2374 			pmc->mca_sfmode = MCAST_INCLUDE;
2375 		/* else no filters; keep old mode for reports */
2376 
2377 		pmc->mca_crcount = idev->mc_qrv;
2378 		idev->mc_ifc_count = pmc->mca_crcount;
2379 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2380 			psf->sf_crcount = 0;
2381 		mld_ifc_event(idev);
2382 	} else if (sf_setstate(pmc))
2383 		mld_ifc_event(idev);
2384 	spin_unlock_bh(&pmc->mca_lock);
2385 	read_unlock_bh(&idev->lock);
2386 	return err;
2387 }
2388 
2389 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2390 {
2391 	struct ip6_sf_list *psf, *nextpsf;
2392 
2393 	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
2394 		nextpsf = psf->sf_next;
2395 		kfree(psf);
2396 	}
2397 	pmc->mca_tomb = NULL;
2398 	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
2399 		nextpsf = psf->sf_next;
2400 		kfree(psf);
2401 	}
2402 	pmc->mca_sources = NULL;
2403 	pmc->mca_sfmode = MCAST_EXCLUDE;
2404 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2405 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2406 }
2407 
2408 
2409 static void igmp6_join_group(struct ifmcaddr6 *ma)
2410 {
2411 	unsigned long delay;
2412 
2413 	if (ma->mca_flags & MAF_NOREPORT)
2414 		return;
2415 
2416 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2417 
2418 	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
2419 
2420 	spin_lock_bh(&ma->mca_lock);
2421 	if (del_timer(&ma->mca_timer)) {
2422 		refcount_dec(&ma->mca_refcnt);
2423 		delay = ma->mca_timer.expires - jiffies;
2424 	}
2425 
2426 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2427 		refcount_inc(&ma->mca_refcnt);
2428 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2429 	spin_unlock_bh(&ma->mca_lock);
2430 }
2431 
2432 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2433 			    struct inet6_dev *idev)
2434 {
2435 	int err;
2436 
2437 	write_lock_bh(&iml->sflock);
2438 	if (!iml->sflist) {
2439 		/* any-source empty exclude case */
2440 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2441 	} else {
2442 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2443 				iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2444 		sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2445 		iml->sflist = NULL;
2446 	}
2447 	write_unlock_bh(&iml->sflock);
2448 	return err;
2449 }
2450 
2451 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2452 {
2453 	if (mld_in_v1_mode(ma->idev)) {
2454 		if (ma->mca_flags & MAF_LAST_REPORTER)
2455 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2456 				ICMPV6_MGM_REDUCTION);
2457 	} else {
2458 		mld_add_delrec(ma->idev, ma);
2459 		mld_ifc_event(ma->idev);
2460 	}
2461 }
2462 
2463 static void mld_gq_timer_expire(struct timer_list *t)
2464 {
2465 	struct inet6_dev *idev = from_timer(idev, t, mc_gq_timer);
2466 
2467 	idev->mc_gq_running = 0;
2468 	mld_send_report(idev, NULL);
2469 	in6_dev_put(idev);
2470 }
2471 
2472 static void mld_ifc_timer_expire(struct timer_list *t)
2473 {
2474 	struct inet6_dev *idev = from_timer(idev, t, mc_ifc_timer);
2475 
2476 	mld_send_cr(idev);
2477 	if (idev->mc_ifc_count) {
2478 		idev->mc_ifc_count--;
2479 		if (idev->mc_ifc_count)
2480 			mld_ifc_start_timer(idev,
2481 					    unsolicited_report_interval(idev));
2482 	}
2483 	in6_dev_put(idev);
2484 }
2485 
2486 static void mld_ifc_event(struct inet6_dev *idev)
2487 {
2488 	if (mld_in_v1_mode(idev))
2489 		return;
2490 	idev->mc_ifc_count = idev->mc_qrv;
2491 	mld_ifc_start_timer(idev, 1);
2492 }
2493 
2494 static void igmp6_timer_handler(struct timer_list *t)
2495 {
2496 	struct ifmcaddr6 *ma = from_timer(ma, t, mca_timer);
2497 
2498 	if (mld_in_v1_mode(ma->idev))
2499 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2500 	else
2501 		mld_send_report(ma->idev, ma);
2502 
2503 	spin_lock(&ma->mca_lock);
2504 	ma->mca_flags |=  MAF_LAST_REPORTER;
2505 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2506 	spin_unlock(&ma->mca_lock);
2507 	ma_put(ma);
2508 }
2509 
2510 /* Device changing type */
2511 
2512 void ipv6_mc_unmap(struct inet6_dev *idev)
2513 {
2514 	struct ifmcaddr6 *i;
2515 
2516 	/* Install multicast list, except for all-nodes (already installed) */
2517 
2518 	read_lock_bh(&idev->lock);
2519 	for (i = idev->mc_list; i; i = i->next)
2520 		igmp6_group_dropped(i);
2521 	read_unlock_bh(&idev->lock);
2522 }
2523 
2524 void ipv6_mc_remap(struct inet6_dev *idev)
2525 {
2526 	ipv6_mc_up(idev);
2527 }
2528 
2529 /* Device going down */
2530 
2531 void ipv6_mc_down(struct inet6_dev *idev)
2532 {
2533 	struct ifmcaddr6 *i;
2534 
2535 	/* Withdraw multicast list */
2536 
2537 	read_lock_bh(&idev->lock);
2538 
2539 	for (i = idev->mc_list; i; i = i->next)
2540 		igmp6_group_dropped(i);
2541 
2542 	/* Should stop timer after group drop. or we will
2543 	 * start timer again in mld_ifc_event()
2544 	 */
2545 	mld_ifc_stop_timer(idev);
2546 	mld_gq_stop_timer(idev);
2547 	mld_dad_stop_timer(idev);
2548 	read_unlock_bh(&idev->lock);
2549 }
2550 
2551 static void ipv6_mc_reset(struct inet6_dev *idev)
2552 {
2553 	idev->mc_qrv = sysctl_mld_qrv;
2554 	idev->mc_qi = MLD_QI_DEFAULT;
2555 	idev->mc_qri = MLD_QRI_DEFAULT;
2556 	idev->mc_v1_seen = 0;
2557 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2558 }
2559 
2560 /* Device going up */
2561 
2562 void ipv6_mc_up(struct inet6_dev *idev)
2563 {
2564 	struct ifmcaddr6 *i;
2565 
2566 	/* Install multicast list, except for all-nodes (already installed) */
2567 
2568 	read_lock_bh(&idev->lock);
2569 	ipv6_mc_reset(idev);
2570 	for (i = idev->mc_list; i; i = i->next) {
2571 		mld_del_delrec(idev, i);
2572 		igmp6_group_added(i);
2573 	}
2574 	read_unlock_bh(&idev->lock);
2575 }
2576 
2577 /* IPv6 device initialization. */
2578 
2579 void ipv6_mc_init_dev(struct inet6_dev *idev)
2580 {
2581 	write_lock_bh(&idev->lock);
2582 	spin_lock_init(&idev->mc_lock);
2583 	idev->mc_gq_running = 0;
2584 	timer_setup(&idev->mc_gq_timer, mld_gq_timer_expire, 0);
2585 	idev->mc_tomb = NULL;
2586 	idev->mc_ifc_count = 0;
2587 	timer_setup(&idev->mc_ifc_timer, mld_ifc_timer_expire, 0);
2588 	timer_setup(&idev->mc_dad_timer, mld_dad_timer_expire, 0);
2589 	ipv6_mc_reset(idev);
2590 	write_unlock_bh(&idev->lock);
2591 }
2592 
2593 /*
2594  *	Device is about to be destroyed: clean up.
2595  */
2596 
2597 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2598 {
2599 	struct ifmcaddr6 *i;
2600 
2601 	/* Deactivate timers */
2602 	ipv6_mc_down(idev);
2603 	mld_clear_delrec(idev);
2604 
2605 	/* Delete all-nodes address. */
2606 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2607 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2608 	 * fail.
2609 	 */
2610 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2611 
2612 	if (idev->cnf.forwarding)
2613 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2614 
2615 	write_lock_bh(&idev->lock);
2616 	while ((i = idev->mc_list) != NULL) {
2617 		idev->mc_list = i->next;
2618 
2619 		write_unlock_bh(&idev->lock);
2620 		ma_put(i);
2621 		write_lock_bh(&idev->lock);
2622 	}
2623 	write_unlock_bh(&idev->lock);
2624 }
2625 
2626 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2627 {
2628 	struct ifmcaddr6 *pmc;
2629 
2630 	ASSERT_RTNL();
2631 
2632 	if (mld_in_v1_mode(idev)) {
2633 		read_lock_bh(&idev->lock);
2634 		for (pmc = idev->mc_list; pmc; pmc = pmc->next)
2635 			igmp6_join_group(pmc);
2636 		read_unlock_bh(&idev->lock);
2637 	} else
2638 		mld_send_report(idev, NULL);
2639 }
2640 
2641 static int ipv6_mc_netdev_event(struct notifier_block *this,
2642 				unsigned long event,
2643 				void *ptr)
2644 {
2645 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2646 	struct inet6_dev *idev = __in6_dev_get(dev);
2647 
2648 	switch (event) {
2649 	case NETDEV_RESEND_IGMP:
2650 		if (idev)
2651 			ipv6_mc_rejoin_groups(idev);
2652 		break;
2653 	default:
2654 		break;
2655 	}
2656 
2657 	return NOTIFY_DONE;
2658 }
2659 
2660 static struct notifier_block igmp6_netdev_notifier = {
2661 	.notifier_call = ipv6_mc_netdev_event,
2662 };
2663 
2664 #ifdef CONFIG_PROC_FS
2665 struct igmp6_mc_iter_state {
2666 	struct seq_net_private p;
2667 	struct net_device *dev;
2668 	struct inet6_dev *idev;
2669 };
2670 
2671 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2672 
2673 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2674 {
2675 	struct ifmcaddr6 *im = NULL;
2676 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2677 	struct net *net = seq_file_net(seq);
2678 
2679 	state->idev = NULL;
2680 	for_each_netdev_rcu(net, state->dev) {
2681 		struct inet6_dev *idev;
2682 		idev = __in6_dev_get(state->dev);
2683 		if (!idev)
2684 			continue;
2685 		read_lock_bh(&idev->lock);
2686 		im = idev->mc_list;
2687 		if (im) {
2688 			state->idev = idev;
2689 			break;
2690 		}
2691 		read_unlock_bh(&idev->lock);
2692 	}
2693 	return im;
2694 }
2695 
2696 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2697 {
2698 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2699 
2700 	im = im->next;
2701 	while (!im) {
2702 		if (likely(state->idev))
2703 			read_unlock_bh(&state->idev->lock);
2704 
2705 		state->dev = next_net_device_rcu(state->dev);
2706 		if (!state->dev) {
2707 			state->idev = NULL;
2708 			break;
2709 		}
2710 		state->idev = __in6_dev_get(state->dev);
2711 		if (!state->idev)
2712 			continue;
2713 		read_lock_bh(&state->idev->lock);
2714 		im = state->idev->mc_list;
2715 	}
2716 	return im;
2717 }
2718 
2719 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2720 {
2721 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2722 	if (im)
2723 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2724 			--pos;
2725 	return pos ? NULL : im;
2726 }
2727 
2728 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2729 	__acquires(RCU)
2730 {
2731 	rcu_read_lock();
2732 	return igmp6_mc_get_idx(seq, *pos);
2733 }
2734 
2735 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2736 {
2737 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2738 
2739 	++*pos;
2740 	return im;
2741 }
2742 
2743 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2744 	__releases(RCU)
2745 {
2746 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2747 
2748 	if (likely(state->idev)) {
2749 		read_unlock_bh(&state->idev->lock);
2750 		state->idev = NULL;
2751 	}
2752 	state->dev = NULL;
2753 	rcu_read_unlock();
2754 }
2755 
2756 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2757 {
2758 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2759 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2760 
2761 	seq_printf(seq,
2762 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2763 		   state->dev->ifindex, state->dev->name,
2764 		   &im->mca_addr,
2765 		   im->mca_users, im->mca_flags,
2766 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2767 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2768 	return 0;
2769 }
2770 
2771 static const struct seq_operations igmp6_mc_seq_ops = {
2772 	.start	=	igmp6_mc_seq_start,
2773 	.next	=	igmp6_mc_seq_next,
2774 	.stop	=	igmp6_mc_seq_stop,
2775 	.show	=	igmp6_mc_seq_show,
2776 };
2777 
2778 struct igmp6_mcf_iter_state {
2779 	struct seq_net_private p;
2780 	struct net_device *dev;
2781 	struct inet6_dev *idev;
2782 	struct ifmcaddr6 *im;
2783 };
2784 
2785 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2786 
2787 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2788 {
2789 	struct ip6_sf_list *psf = NULL;
2790 	struct ifmcaddr6 *im = NULL;
2791 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2792 	struct net *net = seq_file_net(seq);
2793 
2794 	state->idev = NULL;
2795 	state->im = NULL;
2796 	for_each_netdev_rcu(net, state->dev) {
2797 		struct inet6_dev *idev;
2798 		idev = __in6_dev_get(state->dev);
2799 		if (unlikely(idev == NULL))
2800 			continue;
2801 		read_lock_bh(&idev->lock);
2802 		im = idev->mc_list;
2803 		if (likely(im)) {
2804 			spin_lock_bh(&im->mca_lock);
2805 			psf = im->mca_sources;
2806 			if (likely(psf)) {
2807 				state->im = im;
2808 				state->idev = idev;
2809 				break;
2810 			}
2811 			spin_unlock_bh(&im->mca_lock);
2812 		}
2813 		read_unlock_bh(&idev->lock);
2814 	}
2815 	return psf;
2816 }
2817 
2818 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2819 {
2820 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2821 
2822 	psf = psf->sf_next;
2823 	while (!psf) {
2824 		spin_unlock_bh(&state->im->mca_lock);
2825 		state->im = state->im->next;
2826 		while (!state->im) {
2827 			if (likely(state->idev))
2828 				read_unlock_bh(&state->idev->lock);
2829 
2830 			state->dev = next_net_device_rcu(state->dev);
2831 			if (!state->dev) {
2832 				state->idev = NULL;
2833 				goto out;
2834 			}
2835 			state->idev = __in6_dev_get(state->dev);
2836 			if (!state->idev)
2837 				continue;
2838 			read_lock_bh(&state->idev->lock);
2839 			state->im = state->idev->mc_list;
2840 		}
2841 		if (!state->im)
2842 			break;
2843 		spin_lock_bh(&state->im->mca_lock);
2844 		psf = state->im->mca_sources;
2845 	}
2846 out:
2847 	return psf;
2848 }
2849 
2850 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2851 {
2852 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2853 	if (psf)
2854 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2855 			--pos;
2856 	return pos ? NULL : psf;
2857 }
2858 
2859 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2860 	__acquires(RCU)
2861 {
2862 	rcu_read_lock();
2863 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2864 }
2865 
2866 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2867 {
2868 	struct ip6_sf_list *psf;
2869 	if (v == SEQ_START_TOKEN)
2870 		psf = igmp6_mcf_get_first(seq);
2871 	else
2872 		psf = igmp6_mcf_get_next(seq, v);
2873 	++*pos;
2874 	return psf;
2875 }
2876 
2877 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2878 	__releases(RCU)
2879 {
2880 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2881 	if (likely(state->im)) {
2882 		spin_unlock_bh(&state->im->mca_lock);
2883 		state->im = NULL;
2884 	}
2885 	if (likely(state->idev)) {
2886 		read_unlock_bh(&state->idev->lock);
2887 		state->idev = NULL;
2888 	}
2889 	state->dev = NULL;
2890 	rcu_read_unlock();
2891 }
2892 
2893 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2894 {
2895 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2896 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2897 
2898 	if (v == SEQ_START_TOKEN) {
2899 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
2900 	} else {
2901 		seq_printf(seq,
2902 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2903 			   state->dev->ifindex, state->dev->name,
2904 			   &state->im->mca_addr,
2905 			   &psf->sf_addr,
2906 			   psf->sf_count[MCAST_INCLUDE],
2907 			   psf->sf_count[MCAST_EXCLUDE]);
2908 	}
2909 	return 0;
2910 }
2911 
2912 static const struct seq_operations igmp6_mcf_seq_ops = {
2913 	.start	=	igmp6_mcf_seq_start,
2914 	.next	=	igmp6_mcf_seq_next,
2915 	.stop	=	igmp6_mcf_seq_stop,
2916 	.show	=	igmp6_mcf_seq_show,
2917 };
2918 
2919 static int __net_init igmp6_proc_init(struct net *net)
2920 {
2921 	int err;
2922 
2923 	err = -ENOMEM;
2924 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
2925 			sizeof(struct igmp6_mc_iter_state)))
2926 		goto out;
2927 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
2928 			&igmp6_mcf_seq_ops,
2929 			sizeof(struct igmp6_mcf_iter_state)))
2930 		goto out_proc_net_igmp6;
2931 
2932 	err = 0;
2933 out:
2934 	return err;
2935 
2936 out_proc_net_igmp6:
2937 	remove_proc_entry("igmp6", net->proc_net);
2938 	goto out;
2939 }
2940 
2941 static void __net_exit igmp6_proc_exit(struct net *net)
2942 {
2943 	remove_proc_entry("mcfilter6", net->proc_net);
2944 	remove_proc_entry("igmp6", net->proc_net);
2945 }
2946 #else
2947 static inline int igmp6_proc_init(struct net *net)
2948 {
2949 	return 0;
2950 }
2951 static inline void igmp6_proc_exit(struct net *net)
2952 {
2953 }
2954 #endif
2955 
2956 static int __net_init igmp6_net_init(struct net *net)
2957 {
2958 	int err;
2959 
2960 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2961 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2962 	if (err < 0) {
2963 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2964 		       err);
2965 		goto out;
2966 	}
2967 
2968 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2969 
2970 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
2971 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2972 	if (err < 0) {
2973 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
2974 		       err);
2975 		goto out_sock_create;
2976 	}
2977 
2978 	err = igmp6_proc_init(net);
2979 	if (err)
2980 		goto out_sock_create_autojoin;
2981 
2982 	return 0;
2983 
2984 out_sock_create_autojoin:
2985 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2986 out_sock_create:
2987 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2988 out:
2989 	return err;
2990 }
2991 
2992 static void __net_exit igmp6_net_exit(struct net *net)
2993 {
2994 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2995 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2996 	igmp6_proc_exit(net);
2997 }
2998 
2999 static struct pernet_operations igmp6_net_ops = {
3000 	.init = igmp6_net_init,
3001 	.exit = igmp6_net_exit,
3002 };
3003 
3004 int __init igmp6_init(void)
3005 {
3006 	return register_pernet_subsys(&igmp6_net_ops);
3007 }
3008 
3009 int __init igmp6_late_init(void)
3010 {
3011 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3012 }
3013 
3014 void igmp6_cleanup(void)
3015 {
3016 	unregister_pernet_subsys(&igmp6_net_ops);
3017 }
3018 
3019 void igmp6_late_cleanup(void)
3020 {
3021 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3022 }
3023