xref: /openbmc/linux/net/ipv6/mcast.c (revision 8730046c)
1 /*
2  *	Multicast support for IPv6
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *
8  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
9  *
10  *	This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 /* Changes:
17  *
18  *	yoshfuji	: fix format of router-alert option
19  *	YOSHIFUJI Hideaki @USAGI:
20  *		Fixed source address for MLD message based on
21  *		<draft-ietf-magma-mld-source-05.txt>.
22  *	YOSHIFUJI Hideaki @USAGI:
23  *		- Ignore Queries for invalid addresses.
24  *		- MLD for link-local addresses.
25  *	David L Stevens <dlstevens@us.ibm.com>:
26  *		- MLDv2 support
27  */
28 
29 #include <linux/module.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/string.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/jiffies.h>
36 #include <linux/times.h>
37 #include <linux/net.h>
38 #include <linux/in.h>
39 #include <linux/in6.h>
40 #include <linux/netdevice.h>
41 #include <linux/if_arp.h>
42 #include <linux/route.h>
43 #include <linux/init.h>
44 #include <linux/proc_fs.h>
45 #include <linux/seq_file.h>
46 #include <linux/slab.h>
47 #include <linux/pkt_sched.h>
48 #include <net/mld.h>
49 
50 #include <linux/netfilter.h>
51 #include <linux/netfilter_ipv6.h>
52 
53 #include <net/net_namespace.h>
54 #include <net/sock.h>
55 #include <net/snmp.h>
56 
57 #include <net/ipv6.h>
58 #include <net/protocol.h>
59 #include <net/if_inet6.h>
60 #include <net/ndisc.h>
61 #include <net/addrconf.h>
62 #include <net/ip6_route.h>
63 #include <net/inet_common.h>
64 
65 #include <net/ip6_checksum.h>
66 
67 /* Ensure that we have struct in6_addr aligned on 32bit word. */
68 static void *__mld2_query_bugs[] __attribute__((__unused__)) = {
69 	BUILD_BUG_ON_NULL(offsetof(struct mld2_query, mld2q_srcs) % 4),
70 	BUILD_BUG_ON_NULL(offsetof(struct mld2_report, mld2r_grec) % 4),
71 	BUILD_BUG_ON_NULL(offsetof(struct mld2_grec, grec_mca) % 4)
72 };
73 
74 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
75 
76 static void igmp6_join_group(struct ifmcaddr6 *ma);
77 static void igmp6_leave_group(struct ifmcaddr6 *ma);
78 static void igmp6_timer_handler(unsigned long data);
79 
80 static void mld_gq_timer_expire(unsigned long data);
81 static void mld_ifc_timer_expire(unsigned long data);
82 static void mld_ifc_event(struct inet6_dev *idev);
83 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
84 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *addr);
85 static void mld_clear_delrec(struct inet6_dev *idev);
86 static bool mld_in_v1_mode(const struct inet6_dev *idev);
87 static int sf_setstate(struct ifmcaddr6 *pmc);
88 static void sf_markstate(struct ifmcaddr6 *pmc);
89 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
90 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
91 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
92 			  int delta);
93 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
94 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
95 			  int delta);
96 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
97 			    struct inet6_dev *idev);
98 
99 #define MLD_QRV_DEFAULT		2
100 /* RFC3810, 9.2. Query Interval */
101 #define MLD_QI_DEFAULT		(125 * HZ)
102 /* RFC3810, 9.3. Query Response Interval */
103 #define MLD_QRI_DEFAULT		(10 * HZ)
104 
105 /* RFC3810, 8.1 Query Version Distinctions */
106 #define MLD_V1_QUERY_LEN	24
107 #define MLD_V2_QUERY_LEN_MIN	28
108 
109 #define IPV6_MLD_MAX_MSF	64
110 
111 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
112 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
113 
114 /*
115  *	socket join on multicast group
116  */
117 
118 #define for_each_pmc_rcu(np, pmc)				\
119 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
120 	     pmc != NULL;					\
121 	     pmc = rcu_dereference(pmc->next))
122 
123 static int unsolicited_report_interval(struct inet6_dev *idev)
124 {
125 	int iv;
126 
127 	if (mld_in_v1_mode(idev))
128 		iv = idev->cnf.mldv1_unsolicited_report_interval;
129 	else
130 		iv = idev->cnf.mldv2_unsolicited_report_interval;
131 
132 	return iv > 0 ? iv : 1;
133 }
134 
135 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
136 {
137 	struct net_device *dev = NULL;
138 	struct ipv6_mc_socklist *mc_lst;
139 	struct ipv6_pinfo *np = inet6_sk(sk);
140 	struct net *net = sock_net(sk);
141 	int err;
142 
143 	ASSERT_RTNL();
144 
145 	if (!ipv6_addr_is_multicast(addr))
146 		return -EINVAL;
147 
148 	rcu_read_lock();
149 	for_each_pmc_rcu(np, mc_lst) {
150 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
151 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
152 			rcu_read_unlock();
153 			return -EADDRINUSE;
154 		}
155 	}
156 	rcu_read_unlock();
157 
158 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
159 
160 	if (!mc_lst)
161 		return -ENOMEM;
162 
163 	mc_lst->next = NULL;
164 	mc_lst->addr = *addr;
165 
166 	if (ifindex == 0) {
167 		struct rt6_info *rt;
168 		rt = rt6_lookup(net, addr, NULL, 0, 0);
169 		if (rt) {
170 			dev = rt->dst.dev;
171 			ip6_rt_put(rt);
172 		}
173 	} else
174 		dev = __dev_get_by_index(net, ifindex);
175 
176 	if (!dev) {
177 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
178 		return -ENODEV;
179 	}
180 
181 	mc_lst->ifindex = dev->ifindex;
182 	mc_lst->sfmode = MCAST_EXCLUDE;
183 	rwlock_init(&mc_lst->sflock);
184 	mc_lst->sflist = NULL;
185 
186 	/*
187 	 *	now add/increase the group membership on the device
188 	 */
189 
190 	err = ipv6_dev_mc_inc(dev, addr);
191 
192 	if (err) {
193 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
194 		return err;
195 	}
196 
197 	mc_lst->next = np->ipv6_mc_list;
198 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL(ipv6_sock_mc_join);
203 
204 /*
205  *	socket leave on multicast group
206  */
207 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
208 {
209 	struct ipv6_pinfo *np = inet6_sk(sk);
210 	struct ipv6_mc_socklist *mc_lst;
211 	struct ipv6_mc_socklist __rcu **lnk;
212 	struct net *net = sock_net(sk);
213 
214 	ASSERT_RTNL();
215 
216 	if (!ipv6_addr_is_multicast(addr))
217 		return -EINVAL;
218 
219 	for (lnk = &np->ipv6_mc_list;
220 	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
221 	      lnk = &mc_lst->next) {
222 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
223 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
224 			struct net_device *dev;
225 
226 			*lnk = mc_lst->next;
227 
228 			dev = __dev_get_by_index(net, mc_lst->ifindex);
229 			if (dev) {
230 				struct inet6_dev *idev = __in6_dev_get(dev);
231 
232 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
233 				if (idev)
234 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
235 			} else
236 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
237 
238 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
239 			kfree_rcu(mc_lst, rcu);
240 			return 0;
241 		}
242 	}
243 
244 	return -EADDRNOTAVAIL;
245 }
246 EXPORT_SYMBOL(ipv6_sock_mc_drop);
247 
248 /* called with rcu_read_lock() */
249 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
250 					     const struct in6_addr *group,
251 					     int ifindex)
252 {
253 	struct net_device *dev = NULL;
254 	struct inet6_dev *idev = NULL;
255 
256 	if (ifindex == 0) {
257 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, 0);
258 
259 		if (rt) {
260 			dev = rt->dst.dev;
261 			ip6_rt_put(rt);
262 		}
263 	} else
264 		dev = dev_get_by_index_rcu(net, ifindex);
265 
266 	if (!dev)
267 		return NULL;
268 	idev = __in6_dev_get(dev);
269 	if (!idev)
270 		return NULL;
271 	read_lock_bh(&idev->lock);
272 	if (idev->dead) {
273 		read_unlock_bh(&idev->lock);
274 		return NULL;
275 	}
276 	return idev;
277 }
278 
279 void __ipv6_sock_mc_close(struct sock *sk)
280 {
281 	struct ipv6_pinfo *np = inet6_sk(sk);
282 	struct ipv6_mc_socklist *mc_lst;
283 	struct net *net = sock_net(sk);
284 
285 	ASSERT_RTNL();
286 
287 	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
288 		struct net_device *dev;
289 
290 		np->ipv6_mc_list = mc_lst->next;
291 
292 		dev = __dev_get_by_index(net, mc_lst->ifindex);
293 		if (dev) {
294 			struct inet6_dev *idev = __in6_dev_get(dev);
295 
296 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
297 			if (idev)
298 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
299 		} else
300 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
301 
302 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
303 		kfree_rcu(mc_lst, rcu);
304 	}
305 }
306 
307 void ipv6_sock_mc_close(struct sock *sk)
308 {
309 	struct ipv6_pinfo *np = inet6_sk(sk);
310 
311 	if (!rcu_access_pointer(np->ipv6_mc_list))
312 		return;
313 	rtnl_lock();
314 	__ipv6_sock_mc_close(sk);
315 	rtnl_unlock();
316 }
317 
318 int ip6_mc_source(int add, int omode, struct sock *sk,
319 	struct group_source_req *pgsr)
320 {
321 	struct in6_addr *source, *group;
322 	struct ipv6_mc_socklist *pmc;
323 	struct inet6_dev *idev;
324 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
325 	struct ip6_sf_socklist *psl;
326 	struct net *net = sock_net(sk);
327 	int i, j, rv;
328 	int leavegroup = 0;
329 	int pmclocked = 0;
330 	int err;
331 
332 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
333 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
334 
335 	if (!ipv6_addr_is_multicast(group))
336 		return -EINVAL;
337 
338 	rcu_read_lock();
339 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
340 	if (!idev) {
341 		rcu_read_unlock();
342 		return -ENODEV;
343 	}
344 
345 	err = -EADDRNOTAVAIL;
346 
347 	for_each_pmc_rcu(inet6, pmc) {
348 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
349 			continue;
350 		if (ipv6_addr_equal(&pmc->addr, group))
351 			break;
352 	}
353 	if (!pmc) {		/* must have a prior join */
354 		err = -EINVAL;
355 		goto done;
356 	}
357 	/* if a source filter was set, must be the same mode as before */
358 	if (pmc->sflist) {
359 		if (pmc->sfmode != omode) {
360 			err = -EINVAL;
361 			goto done;
362 		}
363 	} else if (pmc->sfmode != omode) {
364 		/* allow mode switches for empty-set filters */
365 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
366 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
367 		pmc->sfmode = omode;
368 	}
369 
370 	write_lock(&pmc->sflock);
371 	pmclocked = 1;
372 
373 	psl = pmc->sflist;
374 	if (!add) {
375 		if (!psl)
376 			goto done;	/* err = -EADDRNOTAVAIL */
377 		rv = !0;
378 		for (i = 0; i < psl->sl_count; i++) {
379 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
380 			if (rv == 0)
381 				break;
382 		}
383 		if (rv)		/* source not found */
384 			goto done;	/* err = -EADDRNOTAVAIL */
385 
386 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
387 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
388 			leavegroup = 1;
389 			goto done;
390 		}
391 
392 		/* update the interface filter */
393 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
394 
395 		for (j = i+1; j < psl->sl_count; j++)
396 			psl->sl_addr[j-1] = psl->sl_addr[j];
397 		psl->sl_count--;
398 		err = 0;
399 		goto done;
400 	}
401 	/* else, add a new source to the filter */
402 
403 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
404 		err = -ENOBUFS;
405 		goto done;
406 	}
407 	if (!psl || psl->sl_count == psl->sl_max) {
408 		struct ip6_sf_socklist *newpsl;
409 		int count = IP6_SFBLOCK;
410 
411 		if (psl)
412 			count += psl->sl_max;
413 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
414 		if (!newpsl) {
415 			err = -ENOBUFS;
416 			goto done;
417 		}
418 		newpsl->sl_max = count;
419 		newpsl->sl_count = count - IP6_SFBLOCK;
420 		if (psl) {
421 			for (i = 0; i < psl->sl_count; i++)
422 				newpsl->sl_addr[i] = psl->sl_addr[i];
423 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
424 		}
425 		pmc->sflist = psl = newpsl;
426 	}
427 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
428 	for (i = 0; i < psl->sl_count; i++) {
429 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
430 		if (rv == 0) /* There is an error in the address. */
431 			goto done;
432 	}
433 	for (j = psl->sl_count-1; j >= i; j--)
434 		psl->sl_addr[j+1] = psl->sl_addr[j];
435 	psl->sl_addr[i] = *source;
436 	psl->sl_count++;
437 	err = 0;
438 	/* update the interface list */
439 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
440 done:
441 	if (pmclocked)
442 		write_unlock(&pmc->sflock);
443 	read_unlock_bh(&idev->lock);
444 	rcu_read_unlock();
445 	if (leavegroup)
446 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
447 	return err;
448 }
449 
450 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
451 {
452 	const struct in6_addr *group;
453 	struct ipv6_mc_socklist *pmc;
454 	struct inet6_dev *idev;
455 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
456 	struct ip6_sf_socklist *newpsl, *psl;
457 	struct net *net = sock_net(sk);
458 	int leavegroup = 0;
459 	int i, err;
460 
461 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
462 
463 	if (!ipv6_addr_is_multicast(group))
464 		return -EINVAL;
465 	if (gsf->gf_fmode != MCAST_INCLUDE &&
466 	    gsf->gf_fmode != MCAST_EXCLUDE)
467 		return -EINVAL;
468 
469 	rcu_read_lock();
470 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
471 
472 	if (!idev) {
473 		rcu_read_unlock();
474 		return -ENODEV;
475 	}
476 
477 	err = 0;
478 
479 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
480 		leavegroup = 1;
481 		goto done;
482 	}
483 
484 	for_each_pmc_rcu(inet6, pmc) {
485 		if (pmc->ifindex != gsf->gf_interface)
486 			continue;
487 		if (ipv6_addr_equal(&pmc->addr, group))
488 			break;
489 	}
490 	if (!pmc) {		/* must have a prior join */
491 		err = -EINVAL;
492 		goto done;
493 	}
494 	if (gsf->gf_numsrc) {
495 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
496 							  GFP_ATOMIC);
497 		if (!newpsl) {
498 			err = -ENOBUFS;
499 			goto done;
500 		}
501 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
502 		for (i = 0; i < newpsl->sl_count; ++i) {
503 			struct sockaddr_in6 *psin6;
504 
505 			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
506 			newpsl->sl_addr[i] = psin6->sin6_addr;
507 		}
508 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
509 			newpsl->sl_count, newpsl->sl_addr, 0);
510 		if (err) {
511 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
512 			goto done;
513 		}
514 	} else {
515 		newpsl = NULL;
516 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
517 	}
518 
519 	write_lock(&pmc->sflock);
520 	psl = pmc->sflist;
521 	if (psl) {
522 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
523 			psl->sl_count, psl->sl_addr, 0);
524 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
525 	} else
526 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
527 	pmc->sflist = newpsl;
528 	pmc->sfmode = gsf->gf_fmode;
529 	write_unlock(&pmc->sflock);
530 	err = 0;
531 done:
532 	read_unlock_bh(&idev->lock);
533 	rcu_read_unlock();
534 	if (leavegroup)
535 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
536 	return err;
537 }
538 
539 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
540 	struct group_filter __user *optval, int __user *optlen)
541 {
542 	int err, i, count, copycount;
543 	const struct in6_addr *group;
544 	struct ipv6_mc_socklist *pmc;
545 	struct inet6_dev *idev;
546 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
547 	struct ip6_sf_socklist *psl;
548 	struct net *net = sock_net(sk);
549 
550 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
551 
552 	if (!ipv6_addr_is_multicast(group))
553 		return -EINVAL;
554 
555 	rcu_read_lock();
556 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
557 
558 	if (!idev) {
559 		rcu_read_unlock();
560 		return -ENODEV;
561 	}
562 
563 	err = -EADDRNOTAVAIL;
564 	/* changes to the ipv6_mc_list require the socket lock and
565 	 * rtnl lock. We have the socket lock and rcu read lock,
566 	 * so reading the list is safe.
567 	 */
568 
569 	for_each_pmc_rcu(inet6, pmc) {
570 		if (pmc->ifindex != gsf->gf_interface)
571 			continue;
572 		if (ipv6_addr_equal(group, &pmc->addr))
573 			break;
574 	}
575 	if (!pmc)		/* must have a prior join */
576 		goto done;
577 	gsf->gf_fmode = pmc->sfmode;
578 	psl = pmc->sflist;
579 	count = psl ? psl->sl_count : 0;
580 	read_unlock_bh(&idev->lock);
581 	rcu_read_unlock();
582 
583 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
584 	gsf->gf_numsrc = count;
585 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
586 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
587 		return -EFAULT;
588 	}
589 	/* changes to psl require the socket lock, and a write lock
590 	 * on pmc->sflock. We have the socket lock so reading here is safe.
591 	 */
592 	for (i = 0; i < copycount; i++) {
593 		struct sockaddr_in6 *psin6;
594 		struct sockaddr_storage ss;
595 
596 		psin6 = (struct sockaddr_in6 *)&ss;
597 		memset(&ss, 0, sizeof(ss));
598 		psin6->sin6_family = AF_INET6;
599 		psin6->sin6_addr = psl->sl_addr[i];
600 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
601 			return -EFAULT;
602 	}
603 	return 0;
604 done:
605 	read_unlock_bh(&idev->lock);
606 	rcu_read_unlock();
607 	return err;
608 }
609 
610 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
611 		    const struct in6_addr *src_addr)
612 {
613 	struct ipv6_pinfo *np = inet6_sk(sk);
614 	struct ipv6_mc_socklist *mc;
615 	struct ip6_sf_socklist *psl;
616 	bool rv = true;
617 
618 	rcu_read_lock();
619 	for_each_pmc_rcu(np, mc) {
620 		if (ipv6_addr_equal(&mc->addr, mc_addr))
621 			break;
622 	}
623 	if (!mc) {
624 		rcu_read_unlock();
625 		return true;
626 	}
627 	read_lock(&mc->sflock);
628 	psl = mc->sflist;
629 	if (!psl) {
630 		rv = mc->sfmode == MCAST_EXCLUDE;
631 	} else {
632 		int i;
633 
634 		for (i = 0; i < psl->sl_count; i++) {
635 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
636 				break;
637 		}
638 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
639 			rv = false;
640 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
641 			rv = false;
642 	}
643 	read_unlock(&mc->sflock);
644 	rcu_read_unlock();
645 
646 	return rv;
647 }
648 
649 static void igmp6_group_added(struct ifmcaddr6 *mc)
650 {
651 	struct net_device *dev = mc->idev->dev;
652 	char buf[MAX_ADDR_LEN];
653 
654 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
655 	    IPV6_ADDR_SCOPE_LINKLOCAL)
656 		return;
657 
658 	spin_lock_bh(&mc->mca_lock);
659 	if (!(mc->mca_flags&MAF_LOADED)) {
660 		mc->mca_flags |= MAF_LOADED;
661 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
662 			dev_mc_add(dev, buf);
663 	}
664 	spin_unlock_bh(&mc->mca_lock);
665 
666 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
667 		return;
668 
669 	if (mld_in_v1_mode(mc->idev)) {
670 		igmp6_join_group(mc);
671 		return;
672 	}
673 	/* else v2 */
674 
675 	mc->mca_crcount = mc->idev->mc_qrv;
676 	mld_ifc_event(mc->idev);
677 }
678 
679 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
680 {
681 	struct net_device *dev = mc->idev->dev;
682 	char buf[MAX_ADDR_LEN];
683 
684 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
685 	    IPV6_ADDR_SCOPE_LINKLOCAL)
686 		return;
687 
688 	spin_lock_bh(&mc->mca_lock);
689 	if (mc->mca_flags&MAF_LOADED) {
690 		mc->mca_flags &= ~MAF_LOADED;
691 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
692 			dev_mc_del(dev, buf);
693 	}
694 
695 	if (mc->mca_flags & MAF_NOREPORT)
696 		goto done;
697 	spin_unlock_bh(&mc->mca_lock);
698 
699 	if (!mc->idev->dead)
700 		igmp6_leave_group(mc);
701 
702 	spin_lock_bh(&mc->mca_lock);
703 	if (del_timer(&mc->mca_timer))
704 		atomic_dec(&mc->mca_refcnt);
705 done:
706 	ip6_mc_clear_src(mc);
707 	spin_unlock_bh(&mc->mca_lock);
708 }
709 
710 /*
711  * deleted ifmcaddr6 manipulation
712  */
713 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
714 {
715 	struct ifmcaddr6 *pmc;
716 
717 	/* this is an "ifmcaddr6" for convenience; only the fields below
718 	 * are actually used. In particular, the refcnt and users are not
719 	 * used for management of the delete list. Using the same structure
720 	 * for deleted items allows change reports to use common code with
721 	 * non-deleted or query-response MCA's.
722 	 */
723 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
724 	if (!pmc)
725 		return;
726 
727 	spin_lock_bh(&im->mca_lock);
728 	spin_lock_init(&pmc->mca_lock);
729 	pmc->idev = im->idev;
730 	in6_dev_hold(idev);
731 	pmc->mca_addr = im->mca_addr;
732 	pmc->mca_crcount = idev->mc_qrv;
733 	pmc->mca_sfmode = im->mca_sfmode;
734 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
735 		struct ip6_sf_list *psf;
736 
737 		pmc->mca_tomb = im->mca_tomb;
738 		pmc->mca_sources = im->mca_sources;
739 		im->mca_tomb = im->mca_sources = NULL;
740 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
741 			psf->sf_crcount = pmc->mca_crcount;
742 	}
743 	spin_unlock_bh(&im->mca_lock);
744 
745 	spin_lock_bh(&idev->mc_lock);
746 	pmc->next = idev->mc_tomb;
747 	idev->mc_tomb = pmc;
748 	spin_unlock_bh(&idev->mc_lock);
749 }
750 
751 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *pmca)
752 {
753 	struct ifmcaddr6 *pmc, *pmc_prev;
754 	struct ip6_sf_list *psf, *psf_next;
755 
756 	spin_lock_bh(&idev->mc_lock);
757 	pmc_prev = NULL;
758 	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
759 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
760 			break;
761 		pmc_prev = pmc;
762 	}
763 	if (pmc) {
764 		if (pmc_prev)
765 			pmc_prev->next = pmc->next;
766 		else
767 			idev->mc_tomb = pmc->next;
768 	}
769 	spin_unlock_bh(&idev->mc_lock);
770 
771 	if (pmc) {
772 		for (psf = pmc->mca_tomb; psf; psf = psf_next) {
773 			psf_next = psf->sf_next;
774 			kfree(psf);
775 		}
776 		in6_dev_put(pmc->idev);
777 		kfree(pmc);
778 	}
779 }
780 
781 static void mld_clear_delrec(struct inet6_dev *idev)
782 {
783 	struct ifmcaddr6 *pmc, *nextpmc;
784 
785 	spin_lock_bh(&idev->mc_lock);
786 	pmc = idev->mc_tomb;
787 	idev->mc_tomb = NULL;
788 	spin_unlock_bh(&idev->mc_lock);
789 
790 	for (; pmc; pmc = nextpmc) {
791 		nextpmc = pmc->next;
792 		ip6_mc_clear_src(pmc);
793 		in6_dev_put(pmc->idev);
794 		kfree(pmc);
795 	}
796 
797 	/* clear dead sources, too */
798 	read_lock_bh(&idev->lock);
799 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
800 		struct ip6_sf_list *psf, *psf_next;
801 
802 		spin_lock_bh(&pmc->mca_lock);
803 		psf = pmc->mca_tomb;
804 		pmc->mca_tomb = NULL;
805 		spin_unlock_bh(&pmc->mca_lock);
806 		for (; psf; psf = psf_next) {
807 			psf_next = psf->sf_next;
808 			kfree(psf);
809 		}
810 	}
811 	read_unlock_bh(&idev->lock);
812 }
813 
814 static void mca_get(struct ifmcaddr6 *mc)
815 {
816 	atomic_inc(&mc->mca_refcnt);
817 }
818 
819 static void ma_put(struct ifmcaddr6 *mc)
820 {
821 	if (atomic_dec_and_test(&mc->mca_refcnt)) {
822 		in6_dev_put(mc->idev);
823 		kfree(mc);
824 	}
825 }
826 
827 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
828 				   const struct in6_addr *addr)
829 {
830 	struct ifmcaddr6 *mc;
831 
832 	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
833 	if (!mc)
834 		return NULL;
835 
836 	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);
837 
838 	mc->mca_addr = *addr;
839 	mc->idev = idev; /* reference taken by caller */
840 	mc->mca_users = 1;
841 	/* mca_stamp should be updated upon changes */
842 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
843 	atomic_set(&mc->mca_refcnt, 1);
844 	spin_lock_init(&mc->mca_lock);
845 
846 	/* initial mode is (EX, empty) */
847 	mc->mca_sfmode = MCAST_EXCLUDE;
848 	mc->mca_sfcount[MCAST_EXCLUDE] = 1;
849 
850 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
851 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
852 		mc->mca_flags |= MAF_NOREPORT;
853 
854 	return mc;
855 }
856 
857 /*
858  *	device multicast group inc (add if not found)
859  */
860 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
861 {
862 	struct ifmcaddr6 *mc;
863 	struct inet6_dev *idev;
864 
865 	ASSERT_RTNL();
866 
867 	/* we need to take a reference on idev */
868 	idev = in6_dev_get(dev);
869 
870 	if (!idev)
871 		return -EINVAL;
872 
873 	write_lock_bh(&idev->lock);
874 	if (idev->dead) {
875 		write_unlock_bh(&idev->lock);
876 		in6_dev_put(idev);
877 		return -ENODEV;
878 	}
879 
880 	for (mc = idev->mc_list; mc; mc = mc->next) {
881 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
882 			mc->mca_users++;
883 			write_unlock_bh(&idev->lock);
884 			ip6_mc_add_src(idev, &mc->mca_addr, MCAST_EXCLUDE, 0,
885 				NULL, 0);
886 			in6_dev_put(idev);
887 			return 0;
888 		}
889 	}
890 
891 	mc = mca_alloc(idev, addr);
892 	if (!mc) {
893 		write_unlock_bh(&idev->lock);
894 		in6_dev_put(idev);
895 		return -ENOMEM;
896 	}
897 
898 	mc->next = idev->mc_list;
899 	idev->mc_list = mc;
900 
901 	/* Hold this for the code below before we unlock,
902 	 * it is already exposed via idev->mc_list.
903 	 */
904 	mca_get(mc);
905 	write_unlock_bh(&idev->lock);
906 
907 	mld_del_delrec(idev, &mc->mca_addr);
908 	igmp6_group_added(mc);
909 	ma_put(mc);
910 	return 0;
911 }
912 
913 /*
914  *	device multicast group del
915  */
916 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
917 {
918 	struct ifmcaddr6 *ma, **map;
919 
920 	ASSERT_RTNL();
921 
922 	write_lock_bh(&idev->lock);
923 	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
924 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
925 			if (--ma->mca_users == 0) {
926 				*map = ma->next;
927 				write_unlock_bh(&idev->lock);
928 
929 				igmp6_group_dropped(ma);
930 
931 				ma_put(ma);
932 				return 0;
933 			}
934 			write_unlock_bh(&idev->lock);
935 			return 0;
936 		}
937 	}
938 	write_unlock_bh(&idev->lock);
939 
940 	return -ENOENT;
941 }
942 
943 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
944 {
945 	struct inet6_dev *idev;
946 	int err;
947 
948 	ASSERT_RTNL();
949 
950 	idev = __in6_dev_get(dev);
951 	if (!idev)
952 		err = -ENODEV;
953 	else
954 		err = __ipv6_dev_mc_dec(idev, addr);
955 
956 	return err;
957 }
958 
959 /*
960  *	check if the interface/address pair is valid
961  */
962 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
963 			 const struct in6_addr *src_addr)
964 {
965 	struct inet6_dev *idev;
966 	struct ifmcaddr6 *mc;
967 	bool rv = false;
968 
969 	rcu_read_lock();
970 	idev = __in6_dev_get(dev);
971 	if (idev) {
972 		read_lock_bh(&idev->lock);
973 		for (mc = idev->mc_list; mc; mc = mc->next) {
974 			if (ipv6_addr_equal(&mc->mca_addr, group))
975 				break;
976 		}
977 		if (mc) {
978 			if (src_addr && !ipv6_addr_any(src_addr)) {
979 				struct ip6_sf_list *psf;
980 
981 				spin_lock_bh(&mc->mca_lock);
982 				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
983 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
984 						break;
985 				}
986 				if (psf)
987 					rv = psf->sf_count[MCAST_INCLUDE] ||
988 						psf->sf_count[MCAST_EXCLUDE] !=
989 						mc->mca_sfcount[MCAST_EXCLUDE];
990 				else
991 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
992 				spin_unlock_bh(&mc->mca_lock);
993 			} else
994 				rv = true; /* don't filter unspecified source */
995 		}
996 		read_unlock_bh(&idev->lock);
997 	}
998 	rcu_read_unlock();
999 	return rv;
1000 }
1001 
1002 static void mld_gq_start_timer(struct inet6_dev *idev)
1003 {
1004 	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
1005 
1006 	idev->mc_gq_running = 1;
1007 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
1008 		in6_dev_hold(idev);
1009 }
1010 
1011 static void mld_gq_stop_timer(struct inet6_dev *idev)
1012 {
1013 	idev->mc_gq_running = 0;
1014 	if (del_timer(&idev->mc_gq_timer))
1015 		__in6_dev_put(idev);
1016 }
1017 
1018 static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
1019 {
1020 	unsigned long tv = prandom_u32() % delay;
1021 
1022 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
1023 		in6_dev_hold(idev);
1024 }
1025 
1026 static void mld_ifc_stop_timer(struct inet6_dev *idev)
1027 {
1028 	idev->mc_ifc_count = 0;
1029 	if (del_timer(&idev->mc_ifc_timer))
1030 		__in6_dev_put(idev);
1031 }
1032 
1033 static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
1034 {
1035 	unsigned long tv = prandom_u32() % delay;
1036 
1037 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1038 		in6_dev_hold(idev);
1039 }
1040 
1041 static void mld_dad_stop_timer(struct inet6_dev *idev)
1042 {
1043 	if (del_timer(&idev->mc_dad_timer))
1044 		__in6_dev_put(idev);
1045 }
1046 
1047 /*
1048  *	IGMP handling (alias multicast ICMPv6 messages)
1049  */
1050 
1051 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1052 {
1053 	unsigned long delay = resptime;
1054 
1055 	/* Do not start timer for these addresses */
1056 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1057 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1058 		return;
1059 
1060 	if (del_timer(&ma->mca_timer)) {
1061 		atomic_dec(&ma->mca_refcnt);
1062 		delay = ma->mca_timer.expires - jiffies;
1063 	}
1064 
1065 	if (delay >= resptime)
1066 		delay = prandom_u32() % resptime;
1067 
1068 	ma->mca_timer.expires = jiffies + delay;
1069 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1070 		atomic_inc(&ma->mca_refcnt);
1071 	ma->mca_flags |= MAF_TIMER_RUNNING;
1072 }
1073 
1074 /* mark EXCLUDE-mode sources */
1075 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1076 			     const struct in6_addr *srcs)
1077 {
1078 	struct ip6_sf_list *psf;
1079 	int i, scount;
1080 
1081 	scount = 0;
1082 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1083 		if (scount == nsrcs)
1084 			break;
1085 		for (i = 0; i < nsrcs; i++) {
1086 			/* skip inactive filters */
1087 			if (psf->sf_count[MCAST_INCLUDE] ||
1088 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1089 			    psf->sf_count[MCAST_EXCLUDE])
1090 				break;
1091 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1092 				scount++;
1093 				break;
1094 			}
1095 		}
1096 	}
1097 	pmc->mca_flags &= ~MAF_GSQUERY;
1098 	if (scount == nsrcs)	/* all sources excluded */
1099 		return false;
1100 	return true;
1101 }
1102 
1103 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1104 			    const struct in6_addr *srcs)
1105 {
1106 	struct ip6_sf_list *psf;
1107 	int i, scount;
1108 
1109 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1110 		return mld_xmarksources(pmc, nsrcs, srcs);
1111 
1112 	/* mark INCLUDE-mode sources */
1113 
1114 	scount = 0;
1115 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1116 		if (scount == nsrcs)
1117 			break;
1118 		for (i = 0; i < nsrcs; i++) {
1119 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1120 				psf->sf_gsresp = 1;
1121 				scount++;
1122 				break;
1123 			}
1124 		}
1125 	}
1126 	if (!scount) {
1127 		pmc->mca_flags &= ~MAF_GSQUERY;
1128 		return false;
1129 	}
1130 	pmc->mca_flags |= MAF_GSQUERY;
1131 	return true;
1132 }
1133 
1134 static int mld_force_mld_version(const struct inet6_dev *idev)
1135 {
1136 	/* Normally, both are 0 here. If enforcement to a particular is
1137 	 * being used, individual device enforcement will have a lower
1138 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1139 	 */
1140 
1141 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1142 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1143 	else
1144 		return idev->cnf.force_mld_version;
1145 }
1146 
1147 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1148 {
1149 	return mld_force_mld_version(idev) == 2;
1150 }
1151 
1152 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1153 {
1154 	return mld_force_mld_version(idev) == 1;
1155 }
1156 
1157 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1158 {
1159 	if (mld_in_v2_mode_only(idev))
1160 		return false;
1161 	if (mld_in_v1_mode_only(idev))
1162 		return true;
1163 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1164 		return true;
1165 
1166 	return false;
1167 }
1168 
1169 static void mld_set_v1_mode(struct inet6_dev *idev)
1170 {
1171 	/* RFC3810, relevant sections:
1172 	 *  - 9.1. Robustness Variable
1173 	 *  - 9.2. Query Interval
1174 	 *  - 9.3. Query Response Interval
1175 	 *  - 9.12. Older Version Querier Present Timeout
1176 	 */
1177 	unsigned long switchback;
1178 
1179 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1180 
1181 	idev->mc_v1_seen = jiffies + switchback;
1182 }
1183 
1184 static void mld_update_qrv(struct inet6_dev *idev,
1185 			   const struct mld2_query *mlh2)
1186 {
1187 	/* RFC3810, relevant sections:
1188 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1189 	 *  - 9.1. Robustness Variable
1190 	 */
1191 
1192 	/* The value of the Robustness Variable MUST NOT be zero,
1193 	 * and SHOULD NOT be one. Catch this here if we ever run
1194 	 * into such a case in future.
1195 	 */
1196 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1197 	WARN_ON(idev->mc_qrv == 0);
1198 
1199 	if (mlh2->mld2q_qrv > 0)
1200 		idev->mc_qrv = mlh2->mld2q_qrv;
1201 
1202 	if (unlikely(idev->mc_qrv < min_qrv)) {
1203 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1204 				     idev->mc_qrv, min_qrv);
1205 		idev->mc_qrv = min_qrv;
1206 	}
1207 }
1208 
1209 static void mld_update_qi(struct inet6_dev *idev,
1210 			  const struct mld2_query *mlh2)
1211 {
1212 	/* RFC3810, relevant sections:
1213 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1214 	 *  - 9.2. Query Interval
1215 	 *  - 9.12. Older Version Querier Present Timeout
1216 	 *    (the [Query Interval] in the last Query received)
1217 	 */
1218 	unsigned long mc_qqi;
1219 
1220 	if (mlh2->mld2q_qqic < 128) {
1221 		mc_qqi = mlh2->mld2q_qqic;
1222 	} else {
1223 		unsigned long mc_man, mc_exp;
1224 
1225 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1226 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1227 
1228 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1229 	}
1230 
1231 	idev->mc_qi = mc_qqi * HZ;
1232 }
1233 
1234 static void mld_update_qri(struct inet6_dev *idev,
1235 			   const struct mld2_query *mlh2)
1236 {
1237 	/* RFC3810, relevant sections:
1238 	 *  - 5.1.3. Maximum Response Code
1239 	 *  - 9.3. Query Response Interval
1240 	 */
1241 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1242 }
1243 
1244 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1245 			  unsigned long *max_delay, bool v1_query)
1246 {
1247 	unsigned long mldv1_md;
1248 
1249 	/* Ignore v1 queries */
1250 	if (mld_in_v2_mode_only(idev))
1251 		return -EINVAL;
1252 
1253 	mldv1_md = ntohs(mld->mld_maxdelay);
1254 
1255 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1256 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1257 	 * only works when the exponential algorithm is not being
1258 	 * used (as MLDv1 is unaware of such things).
1259 	 *
1260 	 * According to the RFC author, the MLDv2 implementations
1261 	 * he's aware of all use a MRC < 32768 on start up queries.
1262 	 *
1263 	 * Thus, should we *ever* encounter something else larger
1264 	 * than that, just assume the maximum possible within our
1265 	 * reach.
1266 	 */
1267 	if (!v1_query)
1268 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1269 
1270 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1271 
1272 	/* MLDv1 router present: we need to go into v1 mode *only*
1273 	 * when an MLDv1 query is received as per section 9.12. of
1274 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1275 	 * queries MUST be of exactly 24 octets.
1276 	 */
1277 	if (v1_query)
1278 		mld_set_v1_mode(idev);
1279 
1280 	/* cancel MLDv2 report timer */
1281 	mld_gq_stop_timer(idev);
1282 	/* cancel the interface change timer */
1283 	mld_ifc_stop_timer(idev);
1284 	/* clear deleted report items */
1285 	mld_clear_delrec(idev);
1286 
1287 	return 0;
1288 }
1289 
1290 static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1291 			  unsigned long *max_delay)
1292 {
1293 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1294 
1295 	mld_update_qrv(idev, mld);
1296 	mld_update_qi(idev, mld);
1297 	mld_update_qri(idev, mld);
1298 
1299 	idev->mc_maxdelay = *max_delay;
1300 
1301 	return 0;
1302 }
1303 
1304 /* called with rcu_read_lock() */
1305 int igmp6_event_query(struct sk_buff *skb)
1306 {
1307 	struct mld2_query *mlh2 = NULL;
1308 	struct ifmcaddr6 *ma;
1309 	const struct in6_addr *group;
1310 	unsigned long max_delay;
1311 	struct inet6_dev *idev;
1312 	struct mld_msg *mld;
1313 	int group_type;
1314 	int mark = 0;
1315 	int len, err;
1316 
1317 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1318 		return -EINVAL;
1319 
1320 	/* compute payload length excluding extension headers */
1321 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1322 	len -= skb_network_header_len(skb);
1323 
1324 	/* RFC3810 6.2
1325 	 * Upon reception of an MLD message that contains a Query, the node
1326 	 * checks if the source address of the message is a valid link-local
1327 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1328 	 * option is present in the Hop-By-Hop Options header of the IPv6
1329 	 * packet.  If any of these checks fails, the packet is dropped.
1330 	 */
1331 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1332 	    ipv6_hdr(skb)->hop_limit != 1 ||
1333 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1334 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1335 		return -EINVAL;
1336 
1337 	idev = __in6_dev_get(skb->dev);
1338 	if (!idev)
1339 		return 0;
1340 
1341 	mld = (struct mld_msg *)icmp6_hdr(skb);
1342 	group = &mld->mld_mca;
1343 	group_type = ipv6_addr_type(group);
1344 
1345 	if (group_type != IPV6_ADDR_ANY &&
1346 	    !(group_type&IPV6_ADDR_MULTICAST))
1347 		return -EINVAL;
1348 
1349 	if (len < MLD_V1_QUERY_LEN) {
1350 		return -EINVAL;
1351 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1352 		err = mld_process_v1(idev, mld, &max_delay,
1353 				     len == MLD_V1_QUERY_LEN);
1354 		if (err < 0)
1355 			return err;
1356 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1357 		int srcs_offset = sizeof(struct mld2_query) -
1358 				  sizeof(struct icmp6hdr);
1359 
1360 		if (!pskb_may_pull(skb, srcs_offset))
1361 			return -EINVAL;
1362 
1363 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1364 
1365 		err = mld_process_v2(idev, mlh2, &max_delay);
1366 		if (err < 0)
1367 			return err;
1368 
1369 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1370 			if (mlh2->mld2q_nsrcs)
1371 				return -EINVAL; /* no sources allowed */
1372 
1373 			mld_gq_start_timer(idev);
1374 			return 0;
1375 		}
1376 		/* mark sources to include, if group & source-specific */
1377 		if (mlh2->mld2q_nsrcs != 0) {
1378 			if (!pskb_may_pull(skb, srcs_offset +
1379 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1380 				return -EINVAL;
1381 
1382 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1383 			mark = 1;
1384 		}
1385 	} else {
1386 		return -EINVAL;
1387 	}
1388 
1389 	read_lock_bh(&idev->lock);
1390 	if (group_type == IPV6_ADDR_ANY) {
1391 		for (ma = idev->mc_list; ma; ma = ma->next) {
1392 			spin_lock_bh(&ma->mca_lock);
1393 			igmp6_group_queried(ma, max_delay);
1394 			spin_unlock_bh(&ma->mca_lock);
1395 		}
1396 	} else {
1397 		for (ma = idev->mc_list; ma; ma = ma->next) {
1398 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1399 				continue;
1400 			spin_lock_bh(&ma->mca_lock);
1401 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1402 				/* gsquery <- gsquery && mark */
1403 				if (!mark)
1404 					ma->mca_flags &= ~MAF_GSQUERY;
1405 			} else {
1406 				/* gsquery <- mark */
1407 				if (mark)
1408 					ma->mca_flags |= MAF_GSQUERY;
1409 				else
1410 					ma->mca_flags &= ~MAF_GSQUERY;
1411 			}
1412 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1413 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1414 				igmp6_group_queried(ma, max_delay);
1415 			spin_unlock_bh(&ma->mca_lock);
1416 			break;
1417 		}
1418 	}
1419 	read_unlock_bh(&idev->lock);
1420 
1421 	return 0;
1422 }
1423 
1424 /* called with rcu_read_lock() */
1425 int igmp6_event_report(struct sk_buff *skb)
1426 {
1427 	struct ifmcaddr6 *ma;
1428 	struct inet6_dev *idev;
1429 	struct mld_msg *mld;
1430 	int addr_type;
1431 
1432 	/* Our own report looped back. Ignore it. */
1433 	if (skb->pkt_type == PACKET_LOOPBACK)
1434 		return 0;
1435 
1436 	/* send our report if the MC router may not have heard this report */
1437 	if (skb->pkt_type != PACKET_MULTICAST &&
1438 	    skb->pkt_type != PACKET_BROADCAST)
1439 		return 0;
1440 
1441 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1442 		return -EINVAL;
1443 
1444 	mld = (struct mld_msg *)icmp6_hdr(skb);
1445 
1446 	/* Drop reports with not link local source */
1447 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1448 	if (addr_type != IPV6_ADDR_ANY &&
1449 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1450 		return -EINVAL;
1451 
1452 	idev = __in6_dev_get(skb->dev);
1453 	if (!idev)
1454 		return -ENODEV;
1455 
1456 	/*
1457 	 *	Cancel the timer for this group
1458 	 */
1459 
1460 	read_lock_bh(&idev->lock);
1461 	for (ma = idev->mc_list; ma; ma = ma->next) {
1462 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1463 			spin_lock(&ma->mca_lock);
1464 			if (del_timer(&ma->mca_timer))
1465 				atomic_dec(&ma->mca_refcnt);
1466 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1467 			spin_unlock(&ma->mca_lock);
1468 			break;
1469 		}
1470 	}
1471 	read_unlock_bh(&idev->lock);
1472 	return 0;
1473 }
1474 
1475 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1476 		  int gdeleted, int sdeleted)
1477 {
1478 	switch (type) {
1479 	case MLD2_MODE_IS_INCLUDE:
1480 	case MLD2_MODE_IS_EXCLUDE:
1481 		if (gdeleted || sdeleted)
1482 			return false;
1483 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1484 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1485 				return true;
1486 			/* don't include if this source is excluded
1487 			 * in all filters
1488 			 */
1489 			if (psf->sf_count[MCAST_INCLUDE])
1490 				return type == MLD2_MODE_IS_INCLUDE;
1491 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1492 				psf->sf_count[MCAST_EXCLUDE];
1493 		}
1494 		return false;
1495 	case MLD2_CHANGE_TO_INCLUDE:
1496 		if (gdeleted || sdeleted)
1497 			return false;
1498 		return psf->sf_count[MCAST_INCLUDE] != 0;
1499 	case MLD2_CHANGE_TO_EXCLUDE:
1500 		if (gdeleted || sdeleted)
1501 			return false;
1502 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1503 		    psf->sf_count[MCAST_INCLUDE])
1504 			return false;
1505 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1506 			psf->sf_count[MCAST_EXCLUDE];
1507 	case MLD2_ALLOW_NEW_SOURCES:
1508 		if (gdeleted || !psf->sf_crcount)
1509 			return false;
1510 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1511 	case MLD2_BLOCK_OLD_SOURCES:
1512 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1513 			return gdeleted || (psf->sf_crcount && sdeleted);
1514 		return psf->sf_crcount && !gdeleted && !sdeleted;
1515 	}
1516 	return false;
1517 }
1518 
1519 static int
1520 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1521 {
1522 	struct ip6_sf_list *psf;
1523 	int scount = 0;
1524 
1525 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1526 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1527 			continue;
1528 		scount++;
1529 	}
1530 	return scount;
1531 }
1532 
1533 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1534 		       struct net_device *dev,
1535 		       const struct in6_addr *saddr,
1536 		       const struct in6_addr *daddr,
1537 		       int proto, int len)
1538 {
1539 	struct ipv6hdr *hdr;
1540 
1541 	skb->protocol = htons(ETH_P_IPV6);
1542 	skb->dev = dev;
1543 
1544 	skb_reset_network_header(skb);
1545 	skb_put(skb, sizeof(struct ipv6hdr));
1546 	hdr = ipv6_hdr(skb);
1547 
1548 	ip6_flow_hdr(hdr, 0, 0);
1549 
1550 	hdr->payload_len = htons(len);
1551 	hdr->nexthdr = proto;
1552 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1553 
1554 	hdr->saddr = *saddr;
1555 	hdr->daddr = *daddr;
1556 }
1557 
1558 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1559 {
1560 	struct net_device *dev = idev->dev;
1561 	struct net *net = dev_net(dev);
1562 	struct sock *sk = net->ipv6.igmp_sk;
1563 	struct sk_buff *skb;
1564 	struct mld2_report *pmr;
1565 	struct in6_addr addr_buf;
1566 	const struct in6_addr *saddr;
1567 	int hlen = LL_RESERVED_SPACE(dev);
1568 	int tlen = dev->needed_tailroom;
1569 	unsigned int size = mtu + hlen + tlen;
1570 	int err;
1571 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1572 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1573 		     IPV6_TLV_PADN, 0 };
1574 
1575 	/* we assume size > sizeof(ra) here */
1576 	/* limit our allocations to order-0 page */
1577 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1578 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1579 
1580 	if (!skb)
1581 		return NULL;
1582 
1583 	skb->priority = TC_PRIO_CONTROL;
1584 	skb_reserve(skb, hlen);
1585 	skb_tailroom_reserve(skb, mtu, tlen);
1586 
1587 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1588 		/* <draft-ietf-magma-mld-source-05.txt>:
1589 		 * use unspecified address as the source address
1590 		 * when a valid link-local address is not available.
1591 		 */
1592 		saddr = &in6addr_any;
1593 	} else
1594 		saddr = &addr_buf;
1595 
1596 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1597 
1598 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
1599 
1600 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1601 	skb_put(skb, sizeof(*pmr));
1602 	pmr = (struct mld2_report *)skb_transport_header(skb);
1603 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1604 	pmr->mld2r_resv1 = 0;
1605 	pmr->mld2r_cksum = 0;
1606 	pmr->mld2r_resv2 = 0;
1607 	pmr->mld2r_ngrec = 0;
1608 	return skb;
1609 }
1610 
1611 static void mld_sendpack(struct sk_buff *skb)
1612 {
1613 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1614 	struct mld2_report *pmr =
1615 			      (struct mld2_report *)skb_transport_header(skb);
1616 	int payload_len, mldlen;
1617 	struct inet6_dev *idev;
1618 	struct net *net = dev_net(skb->dev);
1619 	int err;
1620 	struct flowi6 fl6;
1621 	struct dst_entry *dst;
1622 
1623 	rcu_read_lock();
1624 	idev = __in6_dev_get(skb->dev);
1625 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1626 
1627 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1628 		sizeof(*pip6);
1629 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1630 	pip6->payload_len = htons(payload_len);
1631 
1632 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1633 					   IPPROTO_ICMPV6,
1634 					   csum_partial(skb_transport_header(skb),
1635 							mldlen, 0));
1636 
1637 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1638 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1639 			 skb->dev->ifindex);
1640 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1641 
1642 	err = 0;
1643 	if (IS_ERR(dst)) {
1644 		err = PTR_ERR(dst);
1645 		dst = NULL;
1646 	}
1647 	skb_dst_set(skb, dst);
1648 	if (err)
1649 		goto err_out;
1650 
1651 	payload_len = skb->len;
1652 
1653 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1654 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1655 		      dst_output);
1656 out:
1657 	if (!err) {
1658 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1659 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1660 	} else {
1661 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1662 	}
1663 
1664 	rcu_read_unlock();
1665 	return;
1666 
1667 err_out:
1668 	kfree_skb(skb);
1669 	goto out;
1670 }
1671 
1672 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1673 {
1674 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1675 }
1676 
1677 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1678 	int type, struct mld2_grec **ppgr)
1679 {
1680 	struct net_device *dev = pmc->idev->dev;
1681 	struct mld2_report *pmr;
1682 	struct mld2_grec *pgr;
1683 
1684 	if (!skb)
1685 		skb = mld_newpack(pmc->idev, dev->mtu);
1686 	if (!skb)
1687 		return NULL;
1688 	pgr = (struct mld2_grec *)skb_put(skb, sizeof(struct mld2_grec));
1689 	pgr->grec_type = type;
1690 	pgr->grec_auxwords = 0;
1691 	pgr->grec_nsrcs = 0;
1692 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1693 	pmr = (struct mld2_report *)skb_transport_header(skb);
1694 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1695 	*ppgr = pgr;
1696 	return skb;
1697 }
1698 
1699 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1700 
1701 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1702 	int type, int gdeleted, int sdeleted, int crsend)
1703 {
1704 	struct inet6_dev *idev = pmc->idev;
1705 	struct net_device *dev = idev->dev;
1706 	struct mld2_report *pmr;
1707 	struct mld2_grec *pgr = NULL;
1708 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1709 	int scount, stotal, first, isquery, truncate;
1710 
1711 	if (pmc->mca_flags & MAF_NOREPORT)
1712 		return skb;
1713 
1714 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1715 		  type == MLD2_MODE_IS_EXCLUDE;
1716 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1717 		    type == MLD2_CHANGE_TO_EXCLUDE;
1718 
1719 	stotal = scount = 0;
1720 
1721 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1722 
1723 	if (!*psf_list)
1724 		goto empty_source;
1725 
1726 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1727 
1728 	/* EX and TO_EX get a fresh packet, if needed */
1729 	if (truncate) {
1730 		if (pmr && pmr->mld2r_ngrec &&
1731 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1732 			if (skb)
1733 				mld_sendpack(skb);
1734 			skb = mld_newpack(idev, dev->mtu);
1735 		}
1736 	}
1737 	first = 1;
1738 	psf_prev = NULL;
1739 	for (psf = *psf_list; psf; psf = psf_next) {
1740 		struct in6_addr *psrc;
1741 
1742 		psf_next = psf->sf_next;
1743 
1744 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
1745 			psf_prev = psf;
1746 			continue;
1747 		}
1748 
1749 		/* Based on RFC3810 6.1. Should not send source-list change
1750 		 * records when there is a filter mode change.
1751 		 */
1752 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1753 		     (!gdeleted && pmc->mca_crcount)) &&
1754 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1755 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1756 			goto decrease_sf_crcount;
1757 
1758 		/* clear marks on query responses */
1759 		if (isquery)
1760 			psf->sf_gsresp = 0;
1761 
1762 		if (AVAILABLE(skb) < sizeof(*psrc) +
1763 		    first*sizeof(struct mld2_grec)) {
1764 			if (truncate && !first)
1765 				break;	 /* truncate these */
1766 			if (pgr)
1767 				pgr->grec_nsrcs = htons(scount);
1768 			if (skb)
1769 				mld_sendpack(skb);
1770 			skb = mld_newpack(idev, dev->mtu);
1771 			first = 1;
1772 			scount = 0;
1773 		}
1774 		if (first) {
1775 			skb = add_grhead(skb, pmc, type, &pgr);
1776 			first = 0;
1777 		}
1778 		if (!skb)
1779 			return NULL;
1780 		psrc = (struct in6_addr *)skb_put(skb, sizeof(*psrc));
1781 		*psrc = psf->sf_addr;
1782 		scount++; stotal++;
1783 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1784 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1785 decrease_sf_crcount:
1786 			psf->sf_crcount--;
1787 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1788 				if (psf_prev)
1789 					psf_prev->sf_next = psf->sf_next;
1790 				else
1791 					*psf_list = psf->sf_next;
1792 				kfree(psf);
1793 				continue;
1794 			}
1795 		}
1796 		psf_prev = psf;
1797 	}
1798 
1799 empty_source:
1800 	if (!stotal) {
1801 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1802 		    type == MLD2_BLOCK_OLD_SOURCES)
1803 			return skb;
1804 		if (pmc->mca_crcount || isquery || crsend) {
1805 			/* make sure we have room for group header */
1806 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1807 				mld_sendpack(skb);
1808 				skb = NULL; /* add_grhead will get a new one */
1809 			}
1810 			skb = add_grhead(skb, pmc, type, &pgr);
1811 		}
1812 	}
1813 	if (pgr)
1814 		pgr->grec_nsrcs = htons(scount);
1815 
1816 	if (isquery)
1817 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1818 	return skb;
1819 }
1820 
1821 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1822 {
1823 	struct sk_buff *skb = NULL;
1824 	int type;
1825 
1826 	read_lock_bh(&idev->lock);
1827 	if (!pmc) {
1828 		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1829 			if (pmc->mca_flags & MAF_NOREPORT)
1830 				continue;
1831 			spin_lock_bh(&pmc->mca_lock);
1832 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1833 				type = MLD2_MODE_IS_EXCLUDE;
1834 			else
1835 				type = MLD2_MODE_IS_INCLUDE;
1836 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1837 			spin_unlock_bh(&pmc->mca_lock);
1838 		}
1839 	} else {
1840 		spin_lock_bh(&pmc->mca_lock);
1841 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1842 			type = MLD2_MODE_IS_EXCLUDE;
1843 		else
1844 			type = MLD2_MODE_IS_INCLUDE;
1845 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1846 		spin_unlock_bh(&pmc->mca_lock);
1847 	}
1848 	read_unlock_bh(&idev->lock);
1849 	if (skb)
1850 		mld_sendpack(skb);
1851 }
1852 
1853 /*
1854  * remove zero-count source records from a source filter list
1855  */
1856 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1857 {
1858 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1859 
1860 	psf_prev = NULL;
1861 	for (psf = *ppsf; psf; psf = psf_next) {
1862 		psf_next = psf->sf_next;
1863 		if (psf->sf_crcount == 0) {
1864 			if (psf_prev)
1865 				psf_prev->sf_next = psf->sf_next;
1866 			else
1867 				*ppsf = psf->sf_next;
1868 			kfree(psf);
1869 		} else
1870 			psf_prev = psf;
1871 	}
1872 }
1873 
1874 static void mld_send_cr(struct inet6_dev *idev)
1875 {
1876 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1877 	struct sk_buff *skb = NULL;
1878 	int type, dtype;
1879 
1880 	read_lock_bh(&idev->lock);
1881 	spin_lock(&idev->mc_lock);
1882 
1883 	/* deleted MCA's */
1884 	pmc_prev = NULL;
1885 	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
1886 		pmc_next = pmc->next;
1887 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1888 			type = MLD2_BLOCK_OLD_SOURCES;
1889 			dtype = MLD2_BLOCK_OLD_SOURCES;
1890 			skb = add_grec(skb, pmc, type, 1, 0, 0);
1891 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
1892 		}
1893 		if (pmc->mca_crcount) {
1894 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1895 				type = MLD2_CHANGE_TO_INCLUDE;
1896 				skb = add_grec(skb, pmc, type, 1, 0, 0);
1897 			}
1898 			pmc->mca_crcount--;
1899 			if (pmc->mca_crcount == 0) {
1900 				mld_clear_zeros(&pmc->mca_tomb);
1901 				mld_clear_zeros(&pmc->mca_sources);
1902 			}
1903 		}
1904 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1905 		    !pmc->mca_sources) {
1906 			if (pmc_prev)
1907 				pmc_prev->next = pmc_next;
1908 			else
1909 				idev->mc_tomb = pmc_next;
1910 			in6_dev_put(pmc->idev);
1911 			kfree(pmc);
1912 		} else
1913 			pmc_prev = pmc;
1914 	}
1915 	spin_unlock(&idev->mc_lock);
1916 
1917 	/* change recs */
1918 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1919 		spin_lock_bh(&pmc->mca_lock);
1920 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1921 			type = MLD2_BLOCK_OLD_SOURCES;
1922 			dtype = MLD2_ALLOW_NEW_SOURCES;
1923 		} else {
1924 			type = MLD2_ALLOW_NEW_SOURCES;
1925 			dtype = MLD2_BLOCK_OLD_SOURCES;
1926 		}
1927 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1928 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
1929 
1930 		/* filter mode changes */
1931 		if (pmc->mca_crcount) {
1932 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1933 				type = MLD2_CHANGE_TO_EXCLUDE;
1934 			else
1935 				type = MLD2_CHANGE_TO_INCLUDE;
1936 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1937 			pmc->mca_crcount--;
1938 		}
1939 		spin_unlock_bh(&pmc->mca_lock);
1940 	}
1941 	read_unlock_bh(&idev->lock);
1942 	if (!skb)
1943 		return;
1944 	(void) mld_sendpack(skb);
1945 }
1946 
1947 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1948 {
1949 	struct net *net = dev_net(dev);
1950 	struct sock *sk = net->ipv6.igmp_sk;
1951 	struct inet6_dev *idev;
1952 	struct sk_buff *skb;
1953 	struct mld_msg *hdr;
1954 	const struct in6_addr *snd_addr, *saddr;
1955 	struct in6_addr addr_buf;
1956 	int hlen = LL_RESERVED_SPACE(dev);
1957 	int tlen = dev->needed_tailroom;
1958 	int err, len, payload_len, full_len;
1959 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1960 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1961 		     IPV6_TLV_PADN, 0 };
1962 	struct flowi6 fl6;
1963 	struct dst_entry *dst;
1964 
1965 	if (type == ICMPV6_MGM_REDUCTION)
1966 		snd_addr = &in6addr_linklocal_allrouters;
1967 	else
1968 		snd_addr = addr;
1969 
1970 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
1971 	payload_len = len + sizeof(ra);
1972 	full_len = sizeof(struct ipv6hdr) + payload_len;
1973 
1974 	rcu_read_lock();
1975 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
1976 		      IPSTATS_MIB_OUT, full_len);
1977 	rcu_read_unlock();
1978 
1979 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
1980 
1981 	if (!skb) {
1982 		rcu_read_lock();
1983 		IP6_INC_STATS(net, __in6_dev_get(dev),
1984 			      IPSTATS_MIB_OUTDISCARDS);
1985 		rcu_read_unlock();
1986 		return;
1987 	}
1988 	skb->priority = TC_PRIO_CONTROL;
1989 	skb_reserve(skb, hlen);
1990 
1991 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1992 		/* <draft-ietf-magma-mld-source-05.txt>:
1993 		 * use unspecified address as the source address
1994 		 * when a valid link-local address is not available.
1995 		 */
1996 		saddr = &in6addr_any;
1997 	} else
1998 		saddr = &addr_buf;
1999 
2000 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2001 
2002 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
2003 
2004 	hdr = (struct mld_msg *) skb_put(skb, sizeof(struct mld_msg));
2005 	memset(hdr, 0, sizeof(struct mld_msg));
2006 	hdr->mld_type = type;
2007 	hdr->mld_mca = *addr;
2008 
2009 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2010 					 IPPROTO_ICMPV6,
2011 					 csum_partial(hdr, len, 0));
2012 
2013 	rcu_read_lock();
2014 	idev = __in6_dev_get(skb->dev);
2015 
2016 	icmpv6_flow_init(sk, &fl6, type,
2017 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2018 			 skb->dev->ifindex);
2019 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2020 	if (IS_ERR(dst)) {
2021 		err = PTR_ERR(dst);
2022 		goto err_out;
2023 	}
2024 
2025 	skb_dst_set(skb, dst);
2026 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2027 		      net, sk, skb, NULL, skb->dev,
2028 		      dst_output);
2029 out:
2030 	if (!err) {
2031 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2032 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2033 	} else
2034 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2035 
2036 	rcu_read_unlock();
2037 	return;
2038 
2039 err_out:
2040 	kfree_skb(skb);
2041 	goto out;
2042 }
2043 
2044 static void mld_send_initial_cr(struct inet6_dev *idev)
2045 {
2046 	struct sk_buff *skb;
2047 	struct ifmcaddr6 *pmc;
2048 	int type;
2049 
2050 	if (mld_in_v1_mode(idev))
2051 		return;
2052 
2053 	skb = NULL;
2054 	read_lock_bh(&idev->lock);
2055 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2056 		spin_lock_bh(&pmc->mca_lock);
2057 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2058 			type = MLD2_CHANGE_TO_EXCLUDE;
2059 		else
2060 			type = MLD2_CHANGE_TO_INCLUDE;
2061 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2062 		spin_unlock_bh(&pmc->mca_lock);
2063 	}
2064 	read_unlock_bh(&idev->lock);
2065 	if (skb)
2066 		mld_sendpack(skb);
2067 }
2068 
2069 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2070 {
2071 	idev->mc_dad_count = idev->mc_qrv;
2072 	if (idev->mc_dad_count) {
2073 		mld_send_initial_cr(idev);
2074 		idev->mc_dad_count--;
2075 		if (idev->mc_dad_count)
2076 			mld_dad_start_timer(idev, idev->mc_maxdelay);
2077 	}
2078 }
2079 
2080 static void mld_dad_timer_expire(unsigned long data)
2081 {
2082 	struct inet6_dev *idev = (struct inet6_dev *)data;
2083 
2084 	mld_send_initial_cr(idev);
2085 	if (idev->mc_dad_count) {
2086 		idev->mc_dad_count--;
2087 		if (idev->mc_dad_count)
2088 			mld_dad_start_timer(idev, idev->mc_maxdelay);
2089 	}
2090 	in6_dev_put(idev);
2091 }
2092 
2093 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2094 	const struct in6_addr *psfsrc)
2095 {
2096 	struct ip6_sf_list *psf, *psf_prev;
2097 	int rv = 0;
2098 
2099 	psf_prev = NULL;
2100 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2101 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2102 			break;
2103 		psf_prev = psf;
2104 	}
2105 	if (!psf || psf->sf_count[sfmode] == 0) {
2106 		/* source filter not found, or count wrong =>  bug */
2107 		return -ESRCH;
2108 	}
2109 	psf->sf_count[sfmode]--;
2110 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2111 		struct inet6_dev *idev = pmc->idev;
2112 
2113 		/* no more filters for this source */
2114 		if (psf_prev)
2115 			psf_prev->sf_next = psf->sf_next;
2116 		else
2117 			pmc->mca_sources = psf->sf_next;
2118 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2119 		    !mld_in_v1_mode(idev)) {
2120 			psf->sf_crcount = idev->mc_qrv;
2121 			psf->sf_next = pmc->mca_tomb;
2122 			pmc->mca_tomb = psf;
2123 			rv = 1;
2124 		} else
2125 			kfree(psf);
2126 	}
2127 	return rv;
2128 }
2129 
2130 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2131 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2132 			  int delta)
2133 {
2134 	struct ifmcaddr6 *pmc;
2135 	int	changerec = 0;
2136 	int	i, err;
2137 
2138 	if (!idev)
2139 		return -ENODEV;
2140 	read_lock_bh(&idev->lock);
2141 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2142 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2143 			break;
2144 	}
2145 	if (!pmc) {
2146 		/* MCA not found?? bug */
2147 		read_unlock_bh(&idev->lock);
2148 		return -ESRCH;
2149 	}
2150 	spin_lock_bh(&pmc->mca_lock);
2151 	sf_markstate(pmc);
2152 	if (!delta) {
2153 		if (!pmc->mca_sfcount[sfmode]) {
2154 			spin_unlock_bh(&pmc->mca_lock);
2155 			read_unlock_bh(&idev->lock);
2156 			return -EINVAL;
2157 		}
2158 		pmc->mca_sfcount[sfmode]--;
2159 	}
2160 	err = 0;
2161 	for (i = 0; i < sfcount; i++) {
2162 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2163 
2164 		changerec |= rv > 0;
2165 		if (!err && rv < 0)
2166 			err = rv;
2167 	}
2168 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2169 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2170 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2171 		struct ip6_sf_list *psf;
2172 
2173 		/* filter mode change */
2174 		pmc->mca_sfmode = MCAST_INCLUDE;
2175 		pmc->mca_crcount = idev->mc_qrv;
2176 		idev->mc_ifc_count = pmc->mca_crcount;
2177 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2178 			psf->sf_crcount = 0;
2179 		mld_ifc_event(pmc->idev);
2180 	} else if (sf_setstate(pmc) || changerec)
2181 		mld_ifc_event(pmc->idev);
2182 	spin_unlock_bh(&pmc->mca_lock);
2183 	read_unlock_bh(&idev->lock);
2184 	return err;
2185 }
2186 
2187 /*
2188  * Add multicast single-source filter to the interface list
2189  */
2190 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2191 	const struct in6_addr *psfsrc)
2192 {
2193 	struct ip6_sf_list *psf, *psf_prev;
2194 
2195 	psf_prev = NULL;
2196 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2197 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2198 			break;
2199 		psf_prev = psf;
2200 	}
2201 	if (!psf) {
2202 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2203 		if (!psf)
2204 			return -ENOBUFS;
2205 
2206 		psf->sf_addr = *psfsrc;
2207 		if (psf_prev) {
2208 			psf_prev->sf_next = psf;
2209 		} else
2210 			pmc->mca_sources = psf;
2211 	}
2212 	psf->sf_count[sfmode]++;
2213 	return 0;
2214 }
2215 
2216 static void sf_markstate(struct ifmcaddr6 *pmc)
2217 {
2218 	struct ip6_sf_list *psf;
2219 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2220 
2221 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2222 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2223 			psf->sf_oldin = mca_xcount ==
2224 				psf->sf_count[MCAST_EXCLUDE] &&
2225 				!psf->sf_count[MCAST_INCLUDE];
2226 		} else
2227 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2228 }
2229 
2230 static int sf_setstate(struct ifmcaddr6 *pmc)
2231 {
2232 	struct ip6_sf_list *psf, *dpsf;
2233 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2234 	int qrv = pmc->idev->mc_qrv;
2235 	int new_in, rv;
2236 
2237 	rv = 0;
2238 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2239 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2240 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2241 				!psf->sf_count[MCAST_INCLUDE];
2242 		} else
2243 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2244 		if (new_in) {
2245 			if (!psf->sf_oldin) {
2246 				struct ip6_sf_list *prev = NULL;
2247 
2248 				for (dpsf = pmc->mca_tomb; dpsf;
2249 				     dpsf = dpsf->sf_next) {
2250 					if (ipv6_addr_equal(&dpsf->sf_addr,
2251 					    &psf->sf_addr))
2252 						break;
2253 					prev = dpsf;
2254 				}
2255 				if (dpsf) {
2256 					if (prev)
2257 						prev->sf_next = dpsf->sf_next;
2258 					else
2259 						pmc->mca_tomb = dpsf->sf_next;
2260 					kfree(dpsf);
2261 				}
2262 				psf->sf_crcount = qrv;
2263 				rv++;
2264 			}
2265 		} else if (psf->sf_oldin) {
2266 			psf->sf_crcount = 0;
2267 			/*
2268 			 * add or update "delete" records if an active filter
2269 			 * is now inactive
2270 			 */
2271 			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
2272 				if (ipv6_addr_equal(&dpsf->sf_addr,
2273 				    &psf->sf_addr))
2274 					break;
2275 			if (!dpsf) {
2276 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2277 				if (!dpsf)
2278 					continue;
2279 				*dpsf = *psf;
2280 				/* pmc->mca_lock held by callers */
2281 				dpsf->sf_next = pmc->mca_tomb;
2282 				pmc->mca_tomb = dpsf;
2283 			}
2284 			dpsf->sf_crcount = qrv;
2285 			rv++;
2286 		}
2287 	}
2288 	return rv;
2289 }
2290 
2291 /*
2292  * Add multicast source filter list to the interface list
2293  */
2294 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2295 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2296 			  int delta)
2297 {
2298 	struct ifmcaddr6 *pmc;
2299 	int	isexclude;
2300 	int	i, err;
2301 
2302 	if (!idev)
2303 		return -ENODEV;
2304 	read_lock_bh(&idev->lock);
2305 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2306 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2307 			break;
2308 	}
2309 	if (!pmc) {
2310 		/* MCA not found?? bug */
2311 		read_unlock_bh(&idev->lock);
2312 		return -ESRCH;
2313 	}
2314 	spin_lock_bh(&pmc->mca_lock);
2315 
2316 	sf_markstate(pmc);
2317 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2318 	if (!delta)
2319 		pmc->mca_sfcount[sfmode]++;
2320 	err = 0;
2321 	for (i = 0; i < sfcount; i++) {
2322 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2323 		if (err)
2324 			break;
2325 	}
2326 	if (err) {
2327 		int j;
2328 
2329 		if (!delta)
2330 			pmc->mca_sfcount[sfmode]--;
2331 		for (j = 0; j < i; j++)
2332 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2333 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2334 		struct ip6_sf_list *psf;
2335 
2336 		/* filter mode change */
2337 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2338 			pmc->mca_sfmode = MCAST_EXCLUDE;
2339 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2340 			pmc->mca_sfmode = MCAST_INCLUDE;
2341 		/* else no filters; keep old mode for reports */
2342 
2343 		pmc->mca_crcount = idev->mc_qrv;
2344 		idev->mc_ifc_count = pmc->mca_crcount;
2345 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2346 			psf->sf_crcount = 0;
2347 		mld_ifc_event(idev);
2348 	} else if (sf_setstate(pmc))
2349 		mld_ifc_event(idev);
2350 	spin_unlock_bh(&pmc->mca_lock);
2351 	read_unlock_bh(&idev->lock);
2352 	return err;
2353 }
2354 
2355 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2356 {
2357 	struct ip6_sf_list *psf, *nextpsf;
2358 
2359 	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
2360 		nextpsf = psf->sf_next;
2361 		kfree(psf);
2362 	}
2363 	pmc->mca_tomb = NULL;
2364 	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
2365 		nextpsf = psf->sf_next;
2366 		kfree(psf);
2367 	}
2368 	pmc->mca_sources = NULL;
2369 	pmc->mca_sfmode = MCAST_EXCLUDE;
2370 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2371 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2372 }
2373 
2374 
2375 static void igmp6_join_group(struct ifmcaddr6 *ma)
2376 {
2377 	unsigned long delay;
2378 
2379 	if (ma->mca_flags & MAF_NOREPORT)
2380 		return;
2381 
2382 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2383 
2384 	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
2385 
2386 	spin_lock_bh(&ma->mca_lock);
2387 	if (del_timer(&ma->mca_timer)) {
2388 		atomic_dec(&ma->mca_refcnt);
2389 		delay = ma->mca_timer.expires - jiffies;
2390 	}
2391 
2392 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2393 		atomic_inc(&ma->mca_refcnt);
2394 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2395 	spin_unlock_bh(&ma->mca_lock);
2396 }
2397 
2398 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2399 			    struct inet6_dev *idev)
2400 {
2401 	int err;
2402 
2403 	/* callers have the socket lock and rtnl lock
2404 	 * so no other readers or writers of iml or its sflist
2405 	 */
2406 	if (!iml->sflist) {
2407 		/* any-source empty exclude case */
2408 		return ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2409 	}
2410 	err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2411 		iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2412 	sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2413 	iml->sflist = NULL;
2414 	return err;
2415 }
2416 
2417 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2418 {
2419 	if (mld_in_v1_mode(ma->idev)) {
2420 		if (ma->mca_flags & MAF_LAST_REPORTER)
2421 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2422 				ICMPV6_MGM_REDUCTION);
2423 	} else {
2424 		mld_add_delrec(ma->idev, ma);
2425 		mld_ifc_event(ma->idev);
2426 	}
2427 }
2428 
2429 static void mld_gq_timer_expire(unsigned long data)
2430 {
2431 	struct inet6_dev *idev = (struct inet6_dev *)data;
2432 
2433 	idev->mc_gq_running = 0;
2434 	mld_send_report(idev, NULL);
2435 	in6_dev_put(idev);
2436 }
2437 
2438 static void mld_ifc_timer_expire(unsigned long data)
2439 {
2440 	struct inet6_dev *idev = (struct inet6_dev *)data;
2441 
2442 	mld_send_cr(idev);
2443 	if (idev->mc_ifc_count) {
2444 		idev->mc_ifc_count--;
2445 		if (idev->mc_ifc_count)
2446 			mld_ifc_start_timer(idev, idev->mc_maxdelay);
2447 	}
2448 	in6_dev_put(idev);
2449 }
2450 
2451 static void mld_ifc_event(struct inet6_dev *idev)
2452 {
2453 	if (mld_in_v1_mode(idev))
2454 		return;
2455 	idev->mc_ifc_count = idev->mc_qrv;
2456 	mld_ifc_start_timer(idev, 1);
2457 }
2458 
2459 
2460 static void igmp6_timer_handler(unsigned long data)
2461 {
2462 	struct ifmcaddr6 *ma = (struct ifmcaddr6 *) data;
2463 
2464 	if (mld_in_v1_mode(ma->idev))
2465 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2466 	else
2467 		mld_send_report(ma->idev, ma);
2468 
2469 	spin_lock(&ma->mca_lock);
2470 	ma->mca_flags |=  MAF_LAST_REPORTER;
2471 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2472 	spin_unlock(&ma->mca_lock);
2473 	ma_put(ma);
2474 }
2475 
2476 /* Device changing type */
2477 
2478 void ipv6_mc_unmap(struct inet6_dev *idev)
2479 {
2480 	struct ifmcaddr6 *i;
2481 
2482 	/* Install multicast list, except for all-nodes (already installed) */
2483 
2484 	read_lock_bh(&idev->lock);
2485 	for (i = idev->mc_list; i; i = i->next)
2486 		igmp6_group_dropped(i);
2487 	read_unlock_bh(&idev->lock);
2488 }
2489 
2490 void ipv6_mc_remap(struct inet6_dev *idev)
2491 {
2492 	ipv6_mc_up(idev);
2493 }
2494 
2495 /* Device going down */
2496 
2497 void ipv6_mc_down(struct inet6_dev *idev)
2498 {
2499 	struct ifmcaddr6 *i;
2500 
2501 	/* Withdraw multicast list */
2502 
2503 	read_lock_bh(&idev->lock);
2504 	mld_ifc_stop_timer(idev);
2505 	mld_gq_stop_timer(idev);
2506 	mld_dad_stop_timer(idev);
2507 
2508 	for (i = idev->mc_list; i; i = i->next)
2509 		igmp6_group_dropped(i);
2510 	read_unlock_bh(&idev->lock);
2511 
2512 	mld_clear_delrec(idev);
2513 }
2514 
2515 static void ipv6_mc_reset(struct inet6_dev *idev)
2516 {
2517 	idev->mc_qrv = sysctl_mld_qrv;
2518 	idev->mc_qi = MLD_QI_DEFAULT;
2519 	idev->mc_qri = MLD_QRI_DEFAULT;
2520 	idev->mc_v1_seen = 0;
2521 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2522 }
2523 
2524 /* Device going up */
2525 
2526 void ipv6_mc_up(struct inet6_dev *idev)
2527 {
2528 	struct ifmcaddr6 *i;
2529 
2530 	/* Install multicast list, except for all-nodes (already installed) */
2531 
2532 	read_lock_bh(&idev->lock);
2533 	ipv6_mc_reset(idev);
2534 	for (i = idev->mc_list; i; i = i->next)
2535 		igmp6_group_added(i);
2536 	read_unlock_bh(&idev->lock);
2537 }
2538 
2539 /* IPv6 device initialization. */
2540 
2541 void ipv6_mc_init_dev(struct inet6_dev *idev)
2542 {
2543 	write_lock_bh(&idev->lock);
2544 	spin_lock_init(&idev->mc_lock);
2545 	idev->mc_gq_running = 0;
2546 	setup_timer(&idev->mc_gq_timer, mld_gq_timer_expire,
2547 			(unsigned long)idev);
2548 	idev->mc_tomb = NULL;
2549 	idev->mc_ifc_count = 0;
2550 	setup_timer(&idev->mc_ifc_timer, mld_ifc_timer_expire,
2551 			(unsigned long)idev);
2552 	setup_timer(&idev->mc_dad_timer, mld_dad_timer_expire,
2553 		    (unsigned long)idev);
2554 	ipv6_mc_reset(idev);
2555 	write_unlock_bh(&idev->lock);
2556 }
2557 
2558 /*
2559  *	Device is about to be destroyed: clean up.
2560  */
2561 
2562 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2563 {
2564 	struct ifmcaddr6 *i;
2565 
2566 	/* Deactivate timers */
2567 	ipv6_mc_down(idev);
2568 
2569 	/* Delete all-nodes address. */
2570 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2571 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2572 	 * fail.
2573 	 */
2574 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2575 
2576 	if (idev->cnf.forwarding)
2577 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2578 
2579 	write_lock_bh(&idev->lock);
2580 	while ((i = idev->mc_list) != NULL) {
2581 		idev->mc_list = i->next;
2582 		write_unlock_bh(&idev->lock);
2583 
2584 		igmp6_group_dropped(i);
2585 		ma_put(i);
2586 
2587 		write_lock_bh(&idev->lock);
2588 	}
2589 	write_unlock_bh(&idev->lock);
2590 }
2591 
2592 #ifdef CONFIG_PROC_FS
2593 struct igmp6_mc_iter_state {
2594 	struct seq_net_private p;
2595 	struct net_device *dev;
2596 	struct inet6_dev *idev;
2597 };
2598 
2599 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2600 
2601 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2602 {
2603 	struct ifmcaddr6 *im = NULL;
2604 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2605 	struct net *net = seq_file_net(seq);
2606 
2607 	state->idev = NULL;
2608 	for_each_netdev_rcu(net, state->dev) {
2609 		struct inet6_dev *idev;
2610 		idev = __in6_dev_get(state->dev);
2611 		if (!idev)
2612 			continue;
2613 		read_lock_bh(&idev->lock);
2614 		im = idev->mc_list;
2615 		if (im) {
2616 			state->idev = idev;
2617 			break;
2618 		}
2619 		read_unlock_bh(&idev->lock);
2620 	}
2621 	return im;
2622 }
2623 
2624 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2625 {
2626 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2627 
2628 	im = im->next;
2629 	while (!im) {
2630 		if (likely(state->idev))
2631 			read_unlock_bh(&state->idev->lock);
2632 
2633 		state->dev = next_net_device_rcu(state->dev);
2634 		if (!state->dev) {
2635 			state->idev = NULL;
2636 			break;
2637 		}
2638 		state->idev = __in6_dev_get(state->dev);
2639 		if (!state->idev)
2640 			continue;
2641 		read_lock_bh(&state->idev->lock);
2642 		im = state->idev->mc_list;
2643 	}
2644 	return im;
2645 }
2646 
2647 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2648 {
2649 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2650 	if (im)
2651 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2652 			--pos;
2653 	return pos ? NULL : im;
2654 }
2655 
2656 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2657 	__acquires(RCU)
2658 {
2659 	rcu_read_lock();
2660 	return igmp6_mc_get_idx(seq, *pos);
2661 }
2662 
2663 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2664 {
2665 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2666 
2667 	++*pos;
2668 	return im;
2669 }
2670 
2671 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2672 	__releases(RCU)
2673 {
2674 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2675 
2676 	if (likely(state->idev)) {
2677 		read_unlock_bh(&state->idev->lock);
2678 		state->idev = NULL;
2679 	}
2680 	state->dev = NULL;
2681 	rcu_read_unlock();
2682 }
2683 
2684 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2685 {
2686 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2687 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2688 
2689 	seq_printf(seq,
2690 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2691 		   state->dev->ifindex, state->dev->name,
2692 		   &im->mca_addr,
2693 		   im->mca_users, im->mca_flags,
2694 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2695 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2696 	return 0;
2697 }
2698 
2699 static const struct seq_operations igmp6_mc_seq_ops = {
2700 	.start	=	igmp6_mc_seq_start,
2701 	.next	=	igmp6_mc_seq_next,
2702 	.stop	=	igmp6_mc_seq_stop,
2703 	.show	=	igmp6_mc_seq_show,
2704 };
2705 
2706 static int igmp6_mc_seq_open(struct inode *inode, struct file *file)
2707 {
2708 	return seq_open_net(inode, file, &igmp6_mc_seq_ops,
2709 			    sizeof(struct igmp6_mc_iter_state));
2710 }
2711 
2712 static const struct file_operations igmp6_mc_seq_fops = {
2713 	.owner		=	THIS_MODULE,
2714 	.open		=	igmp6_mc_seq_open,
2715 	.read		=	seq_read,
2716 	.llseek		=	seq_lseek,
2717 	.release	=	seq_release_net,
2718 };
2719 
2720 struct igmp6_mcf_iter_state {
2721 	struct seq_net_private p;
2722 	struct net_device *dev;
2723 	struct inet6_dev *idev;
2724 	struct ifmcaddr6 *im;
2725 };
2726 
2727 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2728 
2729 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2730 {
2731 	struct ip6_sf_list *psf = NULL;
2732 	struct ifmcaddr6 *im = NULL;
2733 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2734 	struct net *net = seq_file_net(seq);
2735 
2736 	state->idev = NULL;
2737 	state->im = NULL;
2738 	for_each_netdev_rcu(net, state->dev) {
2739 		struct inet6_dev *idev;
2740 		idev = __in6_dev_get(state->dev);
2741 		if (unlikely(idev == NULL))
2742 			continue;
2743 		read_lock_bh(&idev->lock);
2744 		im = idev->mc_list;
2745 		if (likely(im)) {
2746 			spin_lock_bh(&im->mca_lock);
2747 			psf = im->mca_sources;
2748 			if (likely(psf)) {
2749 				state->im = im;
2750 				state->idev = idev;
2751 				break;
2752 			}
2753 			spin_unlock_bh(&im->mca_lock);
2754 		}
2755 		read_unlock_bh(&idev->lock);
2756 	}
2757 	return psf;
2758 }
2759 
2760 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2761 {
2762 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2763 
2764 	psf = psf->sf_next;
2765 	while (!psf) {
2766 		spin_unlock_bh(&state->im->mca_lock);
2767 		state->im = state->im->next;
2768 		while (!state->im) {
2769 			if (likely(state->idev))
2770 				read_unlock_bh(&state->idev->lock);
2771 
2772 			state->dev = next_net_device_rcu(state->dev);
2773 			if (!state->dev) {
2774 				state->idev = NULL;
2775 				goto out;
2776 			}
2777 			state->idev = __in6_dev_get(state->dev);
2778 			if (!state->idev)
2779 				continue;
2780 			read_lock_bh(&state->idev->lock);
2781 			state->im = state->idev->mc_list;
2782 		}
2783 		if (!state->im)
2784 			break;
2785 		spin_lock_bh(&state->im->mca_lock);
2786 		psf = state->im->mca_sources;
2787 	}
2788 out:
2789 	return psf;
2790 }
2791 
2792 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2793 {
2794 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2795 	if (psf)
2796 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2797 			--pos;
2798 	return pos ? NULL : psf;
2799 }
2800 
2801 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2802 	__acquires(RCU)
2803 {
2804 	rcu_read_lock();
2805 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2806 }
2807 
2808 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2809 {
2810 	struct ip6_sf_list *psf;
2811 	if (v == SEQ_START_TOKEN)
2812 		psf = igmp6_mcf_get_first(seq);
2813 	else
2814 		psf = igmp6_mcf_get_next(seq, v);
2815 	++*pos;
2816 	return psf;
2817 }
2818 
2819 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2820 	__releases(RCU)
2821 {
2822 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2823 	if (likely(state->im)) {
2824 		spin_unlock_bh(&state->im->mca_lock);
2825 		state->im = NULL;
2826 	}
2827 	if (likely(state->idev)) {
2828 		read_unlock_bh(&state->idev->lock);
2829 		state->idev = NULL;
2830 	}
2831 	state->dev = NULL;
2832 	rcu_read_unlock();
2833 }
2834 
2835 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2836 {
2837 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2838 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2839 
2840 	if (v == SEQ_START_TOKEN) {
2841 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
2842 	} else {
2843 		seq_printf(seq,
2844 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2845 			   state->dev->ifindex, state->dev->name,
2846 			   &state->im->mca_addr,
2847 			   &psf->sf_addr,
2848 			   psf->sf_count[MCAST_INCLUDE],
2849 			   psf->sf_count[MCAST_EXCLUDE]);
2850 	}
2851 	return 0;
2852 }
2853 
2854 static const struct seq_operations igmp6_mcf_seq_ops = {
2855 	.start	=	igmp6_mcf_seq_start,
2856 	.next	=	igmp6_mcf_seq_next,
2857 	.stop	=	igmp6_mcf_seq_stop,
2858 	.show	=	igmp6_mcf_seq_show,
2859 };
2860 
2861 static int igmp6_mcf_seq_open(struct inode *inode, struct file *file)
2862 {
2863 	return seq_open_net(inode, file, &igmp6_mcf_seq_ops,
2864 			    sizeof(struct igmp6_mcf_iter_state));
2865 }
2866 
2867 static const struct file_operations igmp6_mcf_seq_fops = {
2868 	.owner		=	THIS_MODULE,
2869 	.open		=	igmp6_mcf_seq_open,
2870 	.read		=	seq_read,
2871 	.llseek		=	seq_lseek,
2872 	.release	=	seq_release_net,
2873 };
2874 
2875 static int __net_init igmp6_proc_init(struct net *net)
2876 {
2877 	int err;
2878 
2879 	err = -ENOMEM;
2880 	if (!proc_create("igmp6", S_IRUGO, net->proc_net, &igmp6_mc_seq_fops))
2881 		goto out;
2882 	if (!proc_create("mcfilter6", S_IRUGO, net->proc_net,
2883 			 &igmp6_mcf_seq_fops))
2884 		goto out_proc_net_igmp6;
2885 
2886 	err = 0;
2887 out:
2888 	return err;
2889 
2890 out_proc_net_igmp6:
2891 	remove_proc_entry("igmp6", net->proc_net);
2892 	goto out;
2893 }
2894 
2895 static void __net_exit igmp6_proc_exit(struct net *net)
2896 {
2897 	remove_proc_entry("mcfilter6", net->proc_net);
2898 	remove_proc_entry("igmp6", net->proc_net);
2899 }
2900 #else
2901 static inline int igmp6_proc_init(struct net *net)
2902 {
2903 	return 0;
2904 }
2905 static inline void igmp6_proc_exit(struct net *net)
2906 {
2907 }
2908 #endif
2909 
2910 static int __net_init igmp6_net_init(struct net *net)
2911 {
2912 	int err;
2913 
2914 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2915 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2916 	if (err < 0) {
2917 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2918 		       err);
2919 		goto out;
2920 	}
2921 
2922 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2923 
2924 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
2925 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2926 	if (err < 0) {
2927 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
2928 		       err);
2929 		goto out_sock_create;
2930 	}
2931 
2932 	err = igmp6_proc_init(net);
2933 	if (err)
2934 		goto out_sock_create_autojoin;
2935 
2936 	return 0;
2937 
2938 out_sock_create_autojoin:
2939 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2940 out_sock_create:
2941 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2942 out:
2943 	return err;
2944 }
2945 
2946 static void __net_exit igmp6_net_exit(struct net *net)
2947 {
2948 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2949 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2950 	igmp6_proc_exit(net);
2951 }
2952 
2953 static struct pernet_operations igmp6_net_ops = {
2954 	.init = igmp6_net_init,
2955 	.exit = igmp6_net_exit,
2956 };
2957 
2958 int __init igmp6_init(void)
2959 {
2960 	return register_pernet_subsys(&igmp6_net_ops);
2961 }
2962 
2963 void igmp6_cleanup(void)
2964 {
2965 	unregister_pernet_subsys(&igmp6_net_ops);
2966 }
2967