xref: /openbmc/linux/net/ipv6/mcast.c (revision 2fa49589)
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 int __mld2_query_bugs[] __attribute__((__unused__)) = {
69 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
70 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
71 	BUILD_BUG_ON_ZERO(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(struct timer_list *t);
79 
80 static void mld_gq_timer_expire(struct timer_list *t);
81 static void mld_ifc_timer_expire(struct timer_list *t);
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, struct ifmcaddr6 *pmc);
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 static int __ipv6_dev_mc_inc(struct net_device *dev,
99 			     const struct in6_addr *addr, unsigned int mode);
100 
101 #define MLD_QRV_DEFAULT		2
102 /* RFC3810, 9.2. Query Interval */
103 #define MLD_QI_DEFAULT		(125 * HZ)
104 /* RFC3810, 9.3. Query Response Interval */
105 #define MLD_QRI_DEFAULT		(10 * HZ)
106 
107 /* RFC3810, 8.1 Query Version Distinctions */
108 #define MLD_V1_QUERY_LEN	24
109 #define MLD_V2_QUERY_LEN_MIN	28
110 
111 #define IPV6_MLD_MAX_MSF	64
112 
113 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
114 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
115 
116 /*
117  *	socket join on multicast group
118  */
119 
120 #define for_each_pmc_rcu(np, pmc)				\
121 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
122 	     pmc != NULL;					\
123 	     pmc = rcu_dereference(pmc->next))
124 
125 static int unsolicited_report_interval(struct inet6_dev *idev)
126 {
127 	int iv;
128 
129 	if (mld_in_v1_mode(idev))
130 		iv = idev->cnf.mldv1_unsolicited_report_interval;
131 	else
132 		iv = idev->cnf.mldv2_unsolicited_report_interval;
133 
134 	return iv > 0 ? iv : 1;
135 }
136 
137 static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
138 			       const struct in6_addr *addr, unsigned int mode)
139 {
140 	struct net_device *dev = NULL;
141 	struct ipv6_mc_socklist *mc_lst;
142 	struct ipv6_pinfo *np = inet6_sk(sk);
143 	struct net *net = sock_net(sk);
144 	int err;
145 
146 	ASSERT_RTNL();
147 
148 	if (!ipv6_addr_is_multicast(addr))
149 		return -EINVAL;
150 
151 	rcu_read_lock();
152 	for_each_pmc_rcu(np, mc_lst) {
153 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
154 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
155 			rcu_read_unlock();
156 			return -EADDRINUSE;
157 		}
158 	}
159 	rcu_read_unlock();
160 
161 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
162 
163 	if (!mc_lst)
164 		return -ENOMEM;
165 
166 	mc_lst->next = NULL;
167 	mc_lst->addr = *addr;
168 
169 	if (ifindex == 0) {
170 		struct rt6_info *rt;
171 		rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
172 		if (rt) {
173 			dev = rt->dst.dev;
174 			ip6_rt_put(rt);
175 		}
176 	} else
177 		dev = __dev_get_by_index(net, ifindex);
178 
179 	if (!dev) {
180 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
181 		return -ENODEV;
182 	}
183 
184 	mc_lst->ifindex = dev->ifindex;
185 	mc_lst->sfmode = mode;
186 	rwlock_init(&mc_lst->sflock);
187 	mc_lst->sflist = NULL;
188 
189 	/*
190 	 *	now add/increase the group membership on the device
191 	 */
192 
193 	err = __ipv6_dev_mc_inc(dev, addr, mode);
194 
195 	if (err) {
196 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
197 		return err;
198 	}
199 
200 	mc_lst->next = np->ipv6_mc_list;
201 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
202 
203 	return 0;
204 }
205 
206 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
207 {
208 	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
209 }
210 EXPORT_SYMBOL(ipv6_sock_mc_join);
211 
212 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
213 			  const struct in6_addr *addr, unsigned int mode)
214 {
215 	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
216 }
217 
218 /*
219  *	socket leave on multicast group
220  */
221 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
222 {
223 	struct ipv6_pinfo *np = inet6_sk(sk);
224 	struct ipv6_mc_socklist *mc_lst;
225 	struct ipv6_mc_socklist __rcu **lnk;
226 	struct net *net = sock_net(sk);
227 
228 	ASSERT_RTNL();
229 
230 	if (!ipv6_addr_is_multicast(addr))
231 		return -EINVAL;
232 
233 	for (lnk = &np->ipv6_mc_list;
234 	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
235 	      lnk = &mc_lst->next) {
236 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
237 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
238 			struct net_device *dev;
239 
240 			*lnk = mc_lst->next;
241 
242 			dev = __dev_get_by_index(net, mc_lst->ifindex);
243 			if (dev) {
244 				struct inet6_dev *idev = __in6_dev_get(dev);
245 
246 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
247 				if (idev)
248 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
249 			} else
250 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
251 
252 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
253 			kfree_rcu(mc_lst, rcu);
254 			return 0;
255 		}
256 	}
257 
258 	return -EADDRNOTAVAIL;
259 }
260 EXPORT_SYMBOL(ipv6_sock_mc_drop);
261 
262 /* called with rcu_read_lock() */
263 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
264 					     const struct in6_addr *group,
265 					     int ifindex)
266 {
267 	struct net_device *dev = NULL;
268 	struct inet6_dev *idev = NULL;
269 
270 	if (ifindex == 0) {
271 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
272 
273 		if (rt) {
274 			dev = rt->dst.dev;
275 			ip6_rt_put(rt);
276 		}
277 	} else
278 		dev = dev_get_by_index_rcu(net, ifindex);
279 
280 	if (!dev)
281 		return NULL;
282 	idev = __in6_dev_get(dev);
283 	if (!idev)
284 		return NULL;
285 	read_lock_bh(&idev->lock);
286 	if (idev->dead) {
287 		read_unlock_bh(&idev->lock);
288 		return NULL;
289 	}
290 	return idev;
291 }
292 
293 void __ipv6_sock_mc_close(struct sock *sk)
294 {
295 	struct ipv6_pinfo *np = inet6_sk(sk);
296 	struct ipv6_mc_socklist *mc_lst;
297 	struct net *net = sock_net(sk);
298 
299 	ASSERT_RTNL();
300 
301 	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
302 		struct net_device *dev;
303 
304 		np->ipv6_mc_list = mc_lst->next;
305 
306 		dev = __dev_get_by_index(net, mc_lst->ifindex);
307 		if (dev) {
308 			struct inet6_dev *idev = __in6_dev_get(dev);
309 
310 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
311 			if (idev)
312 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
313 		} else
314 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
315 
316 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
317 		kfree_rcu(mc_lst, rcu);
318 	}
319 }
320 
321 void ipv6_sock_mc_close(struct sock *sk)
322 {
323 	struct ipv6_pinfo *np = inet6_sk(sk);
324 
325 	if (!rcu_access_pointer(np->ipv6_mc_list))
326 		return;
327 	rtnl_lock();
328 	__ipv6_sock_mc_close(sk);
329 	rtnl_unlock();
330 }
331 
332 int ip6_mc_source(int add, int omode, struct sock *sk,
333 	struct group_source_req *pgsr)
334 {
335 	struct in6_addr *source, *group;
336 	struct ipv6_mc_socklist *pmc;
337 	struct inet6_dev *idev;
338 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
339 	struct ip6_sf_socklist *psl;
340 	struct net *net = sock_net(sk);
341 	int i, j, rv;
342 	int leavegroup = 0;
343 	int pmclocked = 0;
344 	int err;
345 
346 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
347 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
348 
349 	if (!ipv6_addr_is_multicast(group))
350 		return -EINVAL;
351 
352 	rcu_read_lock();
353 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
354 	if (!idev) {
355 		rcu_read_unlock();
356 		return -ENODEV;
357 	}
358 
359 	err = -EADDRNOTAVAIL;
360 
361 	for_each_pmc_rcu(inet6, pmc) {
362 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
363 			continue;
364 		if (ipv6_addr_equal(&pmc->addr, group))
365 			break;
366 	}
367 	if (!pmc) {		/* must have a prior join */
368 		err = -EINVAL;
369 		goto done;
370 	}
371 	/* if a source filter was set, must be the same mode as before */
372 	if (pmc->sflist) {
373 		if (pmc->sfmode != omode) {
374 			err = -EINVAL;
375 			goto done;
376 		}
377 	} else if (pmc->sfmode != omode) {
378 		/* allow mode switches for empty-set filters */
379 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
380 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
381 		pmc->sfmode = omode;
382 	}
383 
384 	write_lock(&pmc->sflock);
385 	pmclocked = 1;
386 
387 	psl = pmc->sflist;
388 	if (!add) {
389 		if (!psl)
390 			goto done;	/* err = -EADDRNOTAVAIL */
391 		rv = !0;
392 		for (i = 0; i < psl->sl_count; i++) {
393 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
394 			if (rv == 0)
395 				break;
396 		}
397 		if (rv)		/* source not found */
398 			goto done;	/* err = -EADDRNOTAVAIL */
399 
400 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
401 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
402 			leavegroup = 1;
403 			goto done;
404 		}
405 
406 		/* update the interface filter */
407 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
408 
409 		for (j = i+1; j < psl->sl_count; j++)
410 			psl->sl_addr[j-1] = psl->sl_addr[j];
411 		psl->sl_count--;
412 		err = 0;
413 		goto done;
414 	}
415 	/* else, add a new source to the filter */
416 
417 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
418 		err = -ENOBUFS;
419 		goto done;
420 	}
421 	if (!psl || psl->sl_count == psl->sl_max) {
422 		struct ip6_sf_socklist *newpsl;
423 		int count = IP6_SFBLOCK;
424 
425 		if (psl)
426 			count += psl->sl_max;
427 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
428 		if (!newpsl) {
429 			err = -ENOBUFS;
430 			goto done;
431 		}
432 		newpsl->sl_max = count;
433 		newpsl->sl_count = count - IP6_SFBLOCK;
434 		if (psl) {
435 			for (i = 0; i < psl->sl_count; i++)
436 				newpsl->sl_addr[i] = psl->sl_addr[i];
437 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
438 		}
439 		pmc->sflist = psl = newpsl;
440 	}
441 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
442 	for (i = 0; i < psl->sl_count; i++) {
443 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
444 		if (rv == 0) /* There is an error in the address. */
445 			goto done;
446 	}
447 	for (j = psl->sl_count-1; j >= i; j--)
448 		psl->sl_addr[j+1] = psl->sl_addr[j];
449 	psl->sl_addr[i] = *source;
450 	psl->sl_count++;
451 	err = 0;
452 	/* update the interface list */
453 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
454 done:
455 	if (pmclocked)
456 		write_unlock(&pmc->sflock);
457 	read_unlock_bh(&idev->lock);
458 	rcu_read_unlock();
459 	if (leavegroup)
460 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
461 	return err;
462 }
463 
464 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
465 {
466 	const struct in6_addr *group;
467 	struct ipv6_mc_socklist *pmc;
468 	struct inet6_dev *idev;
469 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
470 	struct ip6_sf_socklist *newpsl, *psl;
471 	struct net *net = sock_net(sk);
472 	int leavegroup = 0;
473 	int i, err;
474 
475 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
476 
477 	if (!ipv6_addr_is_multicast(group))
478 		return -EINVAL;
479 	if (gsf->gf_fmode != MCAST_INCLUDE &&
480 	    gsf->gf_fmode != MCAST_EXCLUDE)
481 		return -EINVAL;
482 
483 	rcu_read_lock();
484 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
485 
486 	if (!idev) {
487 		rcu_read_unlock();
488 		return -ENODEV;
489 	}
490 
491 	err = 0;
492 
493 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
494 		leavegroup = 1;
495 		goto done;
496 	}
497 
498 	for_each_pmc_rcu(inet6, pmc) {
499 		if (pmc->ifindex != gsf->gf_interface)
500 			continue;
501 		if (ipv6_addr_equal(&pmc->addr, group))
502 			break;
503 	}
504 	if (!pmc) {		/* must have a prior join */
505 		err = -EINVAL;
506 		goto done;
507 	}
508 	if (gsf->gf_numsrc) {
509 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
510 							  GFP_ATOMIC);
511 		if (!newpsl) {
512 			err = -ENOBUFS;
513 			goto done;
514 		}
515 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
516 		for (i = 0; i < newpsl->sl_count; ++i) {
517 			struct sockaddr_in6 *psin6;
518 
519 			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
520 			newpsl->sl_addr[i] = psin6->sin6_addr;
521 		}
522 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
523 			newpsl->sl_count, newpsl->sl_addr, 0);
524 		if (err) {
525 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
526 			goto done;
527 		}
528 	} else {
529 		newpsl = NULL;
530 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
531 	}
532 
533 	write_lock(&pmc->sflock);
534 	psl = pmc->sflist;
535 	if (psl) {
536 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
537 			psl->sl_count, psl->sl_addr, 0);
538 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
539 	} else
540 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
541 	pmc->sflist = newpsl;
542 	pmc->sfmode = gsf->gf_fmode;
543 	write_unlock(&pmc->sflock);
544 	err = 0;
545 done:
546 	read_unlock_bh(&idev->lock);
547 	rcu_read_unlock();
548 	if (leavegroup)
549 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
550 	return err;
551 }
552 
553 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
554 	struct group_filter __user *optval, int __user *optlen)
555 {
556 	int err, i, count, copycount;
557 	const struct in6_addr *group;
558 	struct ipv6_mc_socklist *pmc;
559 	struct inet6_dev *idev;
560 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
561 	struct ip6_sf_socklist *psl;
562 	struct net *net = sock_net(sk);
563 
564 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
565 
566 	if (!ipv6_addr_is_multicast(group))
567 		return -EINVAL;
568 
569 	rcu_read_lock();
570 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
571 
572 	if (!idev) {
573 		rcu_read_unlock();
574 		return -ENODEV;
575 	}
576 
577 	err = -EADDRNOTAVAIL;
578 	/* changes to the ipv6_mc_list require the socket lock and
579 	 * rtnl lock. We have the socket lock and rcu read lock,
580 	 * so reading the list is safe.
581 	 */
582 
583 	for_each_pmc_rcu(inet6, pmc) {
584 		if (pmc->ifindex != gsf->gf_interface)
585 			continue;
586 		if (ipv6_addr_equal(group, &pmc->addr))
587 			break;
588 	}
589 	if (!pmc)		/* must have a prior join */
590 		goto done;
591 	gsf->gf_fmode = pmc->sfmode;
592 	psl = pmc->sflist;
593 	count = psl ? psl->sl_count : 0;
594 	read_unlock_bh(&idev->lock);
595 	rcu_read_unlock();
596 
597 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
598 	gsf->gf_numsrc = count;
599 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
600 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
601 		return -EFAULT;
602 	}
603 	/* changes to psl require the socket lock, and a write lock
604 	 * on pmc->sflock. We have the socket lock so reading here is safe.
605 	 */
606 	for (i = 0; i < copycount; i++) {
607 		struct sockaddr_in6 *psin6;
608 		struct sockaddr_storage ss;
609 
610 		psin6 = (struct sockaddr_in6 *)&ss;
611 		memset(&ss, 0, sizeof(ss));
612 		psin6->sin6_family = AF_INET6;
613 		psin6->sin6_addr = psl->sl_addr[i];
614 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
615 			return -EFAULT;
616 	}
617 	return 0;
618 done:
619 	read_unlock_bh(&idev->lock);
620 	rcu_read_unlock();
621 	return err;
622 }
623 
624 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
625 		    const struct in6_addr *src_addr)
626 {
627 	struct ipv6_pinfo *np = inet6_sk(sk);
628 	struct ipv6_mc_socklist *mc;
629 	struct ip6_sf_socklist *psl;
630 	bool rv = true;
631 
632 	rcu_read_lock();
633 	for_each_pmc_rcu(np, mc) {
634 		if (ipv6_addr_equal(&mc->addr, mc_addr))
635 			break;
636 	}
637 	if (!mc) {
638 		rcu_read_unlock();
639 		return np->mc_all;
640 	}
641 	read_lock(&mc->sflock);
642 	psl = mc->sflist;
643 	if (!psl) {
644 		rv = mc->sfmode == MCAST_EXCLUDE;
645 	} else {
646 		int i;
647 
648 		for (i = 0; i < psl->sl_count; i++) {
649 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
650 				break;
651 		}
652 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
653 			rv = false;
654 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
655 			rv = false;
656 	}
657 	read_unlock(&mc->sflock);
658 	rcu_read_unlock();
659 
660 	return rv;
661 }
662 
663 static void igmp6_group_added(struct ifmcaddr6 *mc)
664 {
665 	struct net_device *dev = mc->idev->dev;
666 	char buf[MAX_ADDR_LEN];
667 
668 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
669 	    IPV6_ADDR_SCOPE_LINKLOCAL)
670 		return;
671 
672 	spin_lock_bh(&mc->mca_lock);
673 	if (!(mc->mca_flags&MAF_LOADED)) {
674 		mc->mca_flags |= MAF_LOADED;
675 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
676 			dev_mc_add(dev, buf);
677 	}
678 	spin_unlock_bh(&mc->mca_lock);
679 
680 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
681 		return;
682 
683 	if (mld_in_v1_mode(mc->idev)) {
684 		igmp6_join_group(mc);
685 		return;
686 	}
687 	/* else v2 */
688 
689 	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
690 	 * should not send filter-mode change record as the mode
691 	 * should be from IN() to IN(A).
692 	 */
693 	if (mc->mca_sfmode == MCAST_EXCLUDE)
694 		mc->mca_crcount = mc->idev->mc_qrv;
695 
696 	mld_ifc_event(mc->idev);
697 }
698 
699 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
700 {
701 	struct net_device *dev = mc->idev->dev;
702 	char buf[MAX_ADDR_LEN];
703 
704 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
705 	    IPV6_ADDR_SCOPE_LINKLOCAL)
706 		return;
707 
708 	spin_lock_bh(&mc->mca_lock);
709 	if (mc->mca_flags&MAF_LOADED) {
710 		mc->mca_flags &= ~MAF_LOADED;
711 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
712 			dev_mc_del(dev, buf);
713 	}
714 
715 	spin_unlock_bh(&mc->mca_lock);
716 	if (mc->mca_flags & MAF_NOREPORT)
717 		return;
718 
719 	if (!mc->idev->dead)
720 		igmp6_leave_group(mc);
721 
722 	spin_lock_bh(&mc->mca_lock);
723 	if (del_timer(&mc->mca_timer))
724 		refcount_dec(&mc->mca_refcnt);
725 	spin_unlock_bh(&mc->mca_lock);
726 }
727 
728 /*
729  * deleted ifmcaddr6 manipulation
730  */
731 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
732 {
733 	struct ifmcaddr6 *pmc;
734 
735 	/* this is an "ifmcaddr6" for convenience; only the fields below
736 	 * are actually used. In particular, the refcnt and users are not
737 	 * used for management of the delete list. Using the same structure
738 	 * for deleted items allows change reports to use common code with
739 	 * non-deleted or query-response MCA's.
740 	 */
741 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
742 	if (!pmc)
743 		return;
744 
745 	spin_lock_bh(&im->mca_lock);
746 	spin_lock_init(&pmc->mca_lock);
747 	pmc->idev = im->idev;
748 	in6_dev_hold(idev);
749 	pmc->mca_addr = im->mca_addr;
750 	pmc->mca_crcount = idev->mc_qrv;
751 	pmc->mca_sfmode = im->mca_sfmode;
752 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
753 		struct ip6_sf_list *psf;
754 
755 		pmc->mca_tomb = im->mca_tomb;
756 		pmc->mca_sources = im->mca_sources;
757 		im->mca_tomb = im->mca_sources = NULL;
758 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
759 			psf->sf_crcount = pmc->mca_crcount;
760 	}
761 	spin_unlock_bh(&im->mca_lock);
762 
763 	spin_lock_bh(&idev->mc_lock);
764 	pmc->next = idev->mc_tomb;
765 	idev->mc_tomb = pmc;
766 	spin_unlock_bh(&idev->mc_lock);
767 }
768 
769 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
770 {
771 	struct ifmcaddr6 *pmc, *pmc_prev;
772 	struct ip6_sf_list *psf;
773 	struct in6_addr *pmca = &im->mca_addr;
774 
775 	spin_lock_bh(&idev->mc_lock);
776 	pmc_prev = NULL;
777 	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
778 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
779 			break;
780 		pmc_prev = pmc;
781 	}
782 	if (pmc) {
783 		if (pmc_prev)
784 			pmc_prev->next = pmc->next;
785 		else
786 			idev->mc_tomb = pmc->next;
787 	}
788 	spin_unlock_bh(&idev->mc_lock);
789 
790 	spin_lock_bh(&im->mca_lock);
791 	if (pmc) {
792 		im->idev = pmc->idev;
793 		if (im->mca_sfmode == MCAST_INCLUDE) {
794 			im->mca_tomb = pmc->mca_tomb;
795 			im->mca_sources = pmc->mca_sources;
796 			for (psf = im->mca_sources; psf; psf = psf->sf_next)
797 				psf->sf_crcount = idev->mc_qrv;
798 		} else {
799 			im->mca_crcount = idev->mc_qrv;
800 		}
801 		in6_dev_put(pmc->idev);
802 		kfree(pmc);
803 	}
804 	spin_unlock_bh(&im->mca_lock);
805 }
806 
807 static void mld_clear_delrec(struct inet6_dev *idev)
808 {
809 	struct ifmcaddr6 *pmc, *nextpmc;
810 
811 	spin_lock_bh(&idev->mc_lock);
812 	pmc = idev->mc_tomb;
813 	idev->mc_tomb = NULL;
814 	spin_unlock_bh(&idev->mc_lock);
815 
816 	for (; pmc; pmc = nextpmc) {
817 		nextpmc = pmc->next;
818 		ip6_mc_clear_src(pmc);
819 		in6_dev_put(pmc->idev);
820 		kfree(pmc);
821 	}
822 
823 	/* clear dead sources, too */
824 	read_lock_bh(&idev->lock);
825 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
826 		struct ip6_sf_list *psf, *psf_next;
827 
828 		spin_lock_bh(&pmc->mca_lock);
829 		psf = pmc->mca_tomb;
830 		pmc->mca_tomb = NULL;
831 		spin_unlock_bh(&pmc->mca_lock);
832 		for (; psf; psf = psf_next) {
833 			psf_next = psf->sf_next;
834 			kfree(psf);
835 		}
836 	}
837 	read_unlock_bh(&idev->lock);
838 }
839 
840 static void mca_get(struct ifmcaddr6 *mc)
841 {
842 	refcount_inc(&mc->mca_refcnt);
843 }
844 
845 static void ma_put(struct ifmcaddr6 *mc)
846 {
847 	if (refcount_dec_and_test(&mc->mca_refcnt)) {
848 		in6_dev_put(mc->idev);
849 		kfree(mc);
850 	}
851 }
852 
853 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
854 				   const struct in6_addr *addr,
855 				   unsigned int mode)
856 {
857 	struct ifmcaddr6 *mc;
858 
859 	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
860 	if (!mc)
861 		return NULL;
862 
863 	timer_setup(&mc->mca_timer, igmp6_timer_handler, 0);
864 
865 	mc->mca_addr = *addr;
866 	mc->idev = idev; /* reference taken by caller */
867 	mc->mca_users = 1;
868 	/* mca_stamp should be updated upon changes */
869 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
870 	refcount_set(&mc->mca_refcnt, 1);
871 	spin_lock_init(&mc->mca_lock);
872 
873 	mc->mca_sfmode = mode;
874 	mc->mca_sfcount[mode] = 1;
875 
876 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
877 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
878 		mc->mca_flags |= MAF_NOREPORT;
879 
880 	return mc;
881 }
882 
883 /*
884  *	device multicast group inc (add if not found)
885  */
886 static int __ipv6_dev_mc_inc(struct net_device *dev,
887 			     const struct in6_addr *addr, unsigned int mode)
888 {
889 	struct ifmcaddr6 *mc;
890 	struct inet6_dev *idev;
891 
892 	ASSERT_RTNL();
893 
894 	/* we need to take a reference on idev */
895 	idev = in6_dev_get(dev);
896 
897 	if (!idev)
898 		return -EINVAL;
899 
900 	write_lock_bh(&idev->lock);
901 	if (idev->dead) {
902 		write_unlock_bh(&idev->lock);
903 		in6_dev_put(idev);
904 		return -ENODEV;
905 	}
906 
907 	for (mc = idev->mc_list; mc; mc = mc->next) {
908 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
909 			mc->mca_users++;
910 			write_unlock_bh(&idev->lock);
911 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
912 			in6_dev_put(idev);
913 			return 0;
914 		}
915 	}
916 
917 	mc = mca_alloc(idev, addr, mode);
918 	if (!mc) {
919 		write_unlock_bh(&idev->lock);
920 		in6_dev_put(idev);
921 		return -ENOMEM;
922 	}
923 
924 	mc->next = idev->mc_list;
925 	idev->mc_list = mc;
926 
927 	/* Hold this for the code below before we unlock,
928 	 * it is already exposed via idev->mc_list.
929 	 */
930 	mca_get(mc);
931 	write_unlock_bh(&idev->lock);
932 
933 	mld_del_delrec(idev, mc);
934 	igmp6_group_added(mc);
935 	ma_put(mc);
936 	return 0;
937 }
938 
939 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
940 {
941 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
942 }
943 
944 /*
945  *	device multicast group del
946  */
947 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
948 {
949 	struct ifmcaddr6 *ma, **map;
950 
951 	ASSERT_RTNL();
952 
953 	write_lock_bh(&idev->lock);
954 	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
955 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
956 			if (--ma->mca_users == 0) {
957 				*map = ma->next;
958 				write_unlock_bh(&idev->lock);
959 
960 				igmp6_group_dropped(ma);
961 				ip6_mc_clear_src(ma);
962 
963 				ma_put(ma);
964 				return 0;
965 			}
966 			write_unlock_bh(&idev->lock);
967 			return 0;
968 		}
969 	}
970 	write_unlock_bh(&idev->lock);
971 
972 	return -ENOENT;
973 }
974 
975 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
976 {
977 	struct inet6_dev *idev;
978 	int err;
979 
980 	ASSERT_RTNL();
981 
982 	idev = __in6_dev_get(dev);
983 	if (!idev)
984 		err = -ENODEV;
985 	else
986 		err = __ipv6_dev_mc_dec(idev, addr);
987 
988 	return err;
989 }
990 
991 /*
992  *	check if the interface/address pair is valid
993  */
994 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
995 			 const struct in6_addr *src_addr)
996 {
997 	struct inet6_dev *idev;
998 	struct ifmcaddr6 *mc;
999 	bool rv = false;
1000 
1001 	rcu_read_lock();
1002 	idev = __in6_dev_get(dev);
1003 	if (idev) {
1004 		read_lock_bh(&idev->lock);
1005 		for (mc = idev->mc_list; mc; mc = mc->next) {
1006 			if (ipv6_addr_equal(&mc->mca_addr, group))
1007 				break;
1008 		}
1009 		if (mc) {
1010 			if (src_addr && !ipv6_addr_any(src_addr)) {
1011 				struct ip6_sf_list *psf;
1012 
1013 				spin_lock_bh(&mc->mca_lock);
1014 				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
1015 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1016 						break;
1017 				}
1018 				if (psf)
1019 					rv = psf->sf_count[MCAST_INCLUDE] ||
1020 						psf->sf_count[MCAST_EXCLUDE] !=
1021 						mc->mca_sfcount[MCAST_EXCLUDE];
1022 				else
1023 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
1024 				spin_unlock_bh(&mc->mca_lock);
1025 			} else
1026 				rv = true; /* don't filter unspecified source */
1027 		}
1028 		read_unlock_bh(&idev->lock);
1029 	}
1030 	rcu_read_unlock();
1031 	return rv;
1032 }
1033 
1034 static void mld_gq_start_timer(struct inet6_dev *idev)
1035 {
1036 	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
1037 
1038 	idev->mc_gq_running = 1;
1039 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
1040 		in6_dev_hold(idev);
1041 }
1042 
1043 static void mld_gq_stop_timer(struct inet6_dev *idev)
1044 {
1045 	idev->mc_gq_running = 0;
1046 	if (del_timer(&idev->mc_gq_timer))
1047 		__in6_dev_put(idev);
1048 }
1049 
1050 static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
1051 {
1052 	unsigned long tv = prandom_u32() % delay;
1053 
1054 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
1055 		in6_dev_hold(idev);
1056 }
1057 
1058 static void mld_ifc_stop_timer(struct inet6_dev *idev)
1059 {
1060 	idev->mc_ifc_count = 0;
1061 	if (del_timer(&idev->mc_ifc_timer))
1062 		__in6_dev_put(idev);
1063 }
1064 
1065 static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
1066 {
1067 	unsigned long tv = prandom_u32() % delay;
1068 
1069 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1070 		in6_dev_hold(idev);
1071 }
1072 
1073 static void mld_dad_stop_timer(struct inet6_dev *idev)
1074 {
1075 	if (del_timer(&idev->mc_dad_timer))
1076 		__in6_dev_put(idev);
1077 }
1078 
1079 /*
1080  *	IGMP handling (alias multicast ICMPv6 messages)
1081  */
1082 
1083 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1084 {
1085 	unsigned long delay = resptime;
1086 
1087 	/* Do not start timer for these addresses */
1088 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1089 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1090 		return;
1091 
1092 	if (del_timer(&ma->mca_timer)) {
1093 		refcount_dec(&ma->mca_refcnt);
1094 		delay = ma->mca_timer.expires - jiffies;
1095 	}
1096 
1097 	if (delay >= resptime)
1098 		delay = prandom_u32() % resptime;
1099 
1100 	ma->mca_timer.expires = jiffies + delay;
1101 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1102 		refcount_inc(&ma->mca_refcnt);
1103 	ma->mca_flags |= MAF_TIMER_RUNNING;
1104 }
1105 
1106 /* mark EXCLUDE-mode sources */
1107 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1108 			     const struct in6_addr *srcs)
1109 {
1110 	struct ip6_sf_list *psf;
1111 	int i, scount;
1112 
1113 	scount = 0;
1114 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1115 		if (scount == nsrcs)
1116 			break;
1117 		for (i = 0; i < nsrcs; i++) {
1118 			/* skip inactive filters */
1119 			if (psf->sf_count[MCAST_INCLUDE] ||
1120 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1121 			    psf->sf_count[MCAST_EXCLUDE])
1122 				break;
1123 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1124 				scount++;
1125 				break;
1126 			}
1127 		}
1128 	}
1129 	pmc->mca_flags &= ~MAF_GSQUERY;
1130 	if (scount == nsrcs)	/* all sources excluded */
1131 		return false;
1132 	return true;
1133 }
1134 
1135 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1136 			    const struct in6_addr *srcs)
1137 {
1138 	struct ip6_sf_list *psf;
1139 	int i, scount;
1140 
1141 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1142 		return mld_xmarksources(pmc, nsrcs, srcs);
1143 
1144 	/* mark INCLUDE-mode sources */
1145 
1146 	scount = 0;
1147 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1148 		if (scount == nsrcs)
1149 			break;
1150 		for (i = 0; i < nsrcs; i++) {
1151 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1152 				psf->sf_gsresp = 1;
1153 				scount++;
1154 				break;
1155 			}
1156 		}
1157 	}
1158 	if (!scount) {
1159 		pmc->mca_flags &= ~MAF_GSQUERY;
1160 		return false;
1161 	}
1162 	pmc->mca_flags |= MAF_GSQUERY;
1163 	return true;
1164 }
1165 
1166 static int mld_force_mld_version(const struct inet6_dev *idev)
1167 {
1168 	/* Normally, both are 0 here. If enforcement to a particular is
1169 	 * being used, individual device enforcement will have a lower
1170 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1171 	 */
1172 
1173 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1174 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1175 	else
1176 		return idev->cnf.force_mld_version;
1177 }
1178 
1179 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1180 {
1181 	return mld_force_mld_version(idev) == 2;
1182 }
1183 
1184 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1185 {
1186 	return mld_force_mld_version(idev) == 1;
1187 }
1188 
1189 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1190 {
1191 	if (mld_in_v2_mode_only(idev))
1192 		return false;
1193 	if (mld_in_v1_mode_only(idev))
1194 		return true;
1195 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1196 		return true;
1197 
1198 	return false;
1199 }
1200 
1201 static void mld_set_v1_mode(struct inet6_dev *idev)
1202 {
1203 	/* RFC3810, relevant sections:
1204 	 *  - 9.1. Robustness Variable
1205 	 *  - 9.2. Query Interval
1206 	 *  - 9.3. Query Response Interval
1207 	 *  - 9.12. Older Version Querier Present Timeout
1208 	 */
1209 	unsigned long switchback;
1210 
1211 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1212 
1213 	idev->mc_v1_seen = jiffies + switchback;
1214 }
1215 
1216 static void mld_update_qrv(struct inet6_dev *idev,
1217 			   const struct mld2_query *mlh2)
1218 {
1219 	/* RFC3810, relevant sections:
1220 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1221 	 *  - 9.1. Robustness Variable
1222 	 */
1223 
1224 	/* The value of the Robustness Variable MUST NOT be zero,
1225 	 * and SHOULD NOT be one. Catch this here if we ever run
1226 	 * into such a case in future.
1227 	 */
1228 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1229 	WARN_ON(idev->mc_qrv == 0);
1230 
1231 	if (mlh2->mld2q_qrv > 0)
1232 		idev->mc_qrv = mlh2->mld2q_qrv;
1233 
1234 	if (unlikely(idev->mc_qrv < min_qrv)) {
1235 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1236 				     idev->mc_qrv, min_qrv);
1237 		idev->mc_qrv = min_qrv;
1238 	}
1239 }
1240 
1241 static void mld_update_qi(struct inet6_dev *idev,
1242 			  const struct mld2_query *mlh2)
1243 {
1244 	/* RFC3810, relevant sections:
1245 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1246 	 *  - 9.2. Query Interval
1247 	 *  - 9.12. Older Version Querier Present Timeout
1248 	 *    (the [Query Interval] in the last Query received)
1249 	 */
1250 	unsigned long mc_qqi;
1251 
1252 	if (mlh2->mld2q_qqic < 128) {
1253 		mc_qqi = mlh2->mld2q_qqic;
1254 	} else {
1255 		unsigned long mc_man, mc_exp;
1256 
1257 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1258 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1259 
1260 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1261 	}
1262 
1263 	idev->mc_qi = mc_qqi * HZ;
1264 }
1265 
1266 static void mld_update_qri(struct inet6_dev *idev,
1267 			   const struct mld2_query *mlh2)
1268 {
1269 	/* RFC3810, relevant sections:
1270 	 *  - 5.1.3. Maximum Response Code
1271 	 *  - 9.3. Query Response Interval
1272 	 */
1273 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1274 }
1275 
1276 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1277 			  unsigned long *max_delay, bool v1_query)
1278 {
1279 	unsigned long mldv1_md;
1280 
1281 	/* Ignore v1 queries */
1282 	if (mld_in_v2_mode_only(idev))
1283 		return -EINVAL;
1284 
1285 	mldv1_md = ntohs(mld->mld_maxdelay);
1286 
1287 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1288 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1289 	 * only works when the exponential algorithm is not being
1290 	 * used (as MLDv1 is unaware of such things).
1291 	 *
1292 	 * According to the RFC author, the MLDv2 implementations
1293 	 * he's aware of all use a MRC < 32768 on start up queries.
1294 	 *
1295 	 * Thus, should we *ever* encounter something else larger
1296 	 * than that, just assume the maximum possible within our
1297 	 * reach.
1298 	 */
1299 	if (!v1_query)
1300 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1301 
1302 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1303 
1304 	/* MLDv1 router present: we need to go into v1 mode *only*
1305 	 * when an MLDv1 query is received as per section 9.12. of
1306 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1307 	 * queries MUST be of exactly 24 octets.
1308 	 */
1309 	if (v1_query)
1310 		mld_set_v1_mode(idev);
1311 
1312 	/* cancel MLDv2 report timer */
1313 	mld_gq_stop_timer(idev);
1314 	/* cancel the interface change timer */
1315 	mld_ifc_stop_timer(idev);
1316 	/* clear deleted report items */
1317 	mld_clear_delrec(idev);
1318 
1319 	return 0;
1320 }
1321 
1322 static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1323 			  unsigned long *max_delay)
1324 {
1325 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1326 
1327 	mld_update_qrv(idev, mld);
1328 	mld_update_qi(idev, mld);
1329 	mld_update_qri(idev, mld);
1330 
1331 	idev->mc_maxdelay = *max_delay;
1332 
1333 	return 0;
1334 }
1335 
1336 /* called with rcu_read_lock() */
1337 int igmp6_event_query(struct sk_buff *skb)
1338 {
1339 	struct mld2_query *mlh2 = NULL;
1340 	struct ifmcaddr6 *ma;
1341 	const struct in6_addr *group;
1342 	unsigned long max_delay;
1343 	struct inet6_dev *idev;
1344 	struct mld_msg *mld;
1345 	int group_type;
1346 	int mark = 0;
1347 	int len, err;
1348 
1349 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1350 		return -EINVAL;
1351 
1352 	/* compute payload length excluding extension headers */
1353 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1354 	len -= skb_network_header_len(skb);
1355 
1356 	/* RFC3810 6.2
1357 	 * Upon reception of an MLD message that contains a Query, the node
1358 	 * checks if the source address of the message is a valid link-local
1359 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1360 	 * option is present in the Hop-By-Hop Options header of the IPv6
1361 	 * packet.  If any of these checks fails, the packet is dropped.
1362 	 */
1363 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1364 	    ipv6_hdr(skb)->hop_limit != 1 ||
1365 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1366 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1367 		return -EINVAL;
1368 
1369 	idev = __in6_dev_get(skb->dev);
1370 	if (!idev)
1371 		return 0;
1372 
1373 	mld = (struct mld_msg *)icmp6_hdr(skb);
1374 	group = &mld->mld_mca;
1375 	group_type = ipv6_addr_type(group);
1376 
1377 	if (group_type != IPV6_ADDR_ANY &&
1378 	    !(group_type&IPV6_ADDR_MULTICAST))
1379 		return -EINVAL;
1380 
1381 	if (len < MLD_V1_QUERY_LEN) {
1382 		return -EINVAL;
1383 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1384 		err = mld_process_v1(idev, mld, &max_delay,
1385 				     len == MLD_V1_QUERY_LEN);
1386 		if (err < 0)
1387 			return err;
1388 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1389 		int srcs_offset = sizeof(struct mld2_query) -
1390 				  sizeof(struct icmp6hdr);
1391 
1392 		if (!pskb_may_pull(skb, srcs_offset))
1393 			return -EINVAL;
1394 
1395 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1396 
1397 		err = mld_process_v2(idev, mlh2, &max_delay);
1398 		if (err < 0)
1399 			return err;
1400 
1401 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1402 			if (mlh2->mld2q_nsrcs)
1403 				return -EINVAL; /* no sources allowed */
1404 
1405 			mld_gq_start_timer(idev);
1406 			return 0;
1407 		}
1408 		/* mark sources to include, if group & source-specific */
1409 		if (mlh2->mld2q_nsrcs != 0) {
1410 			if (!pskb_may_pull(skb, srcs_offset +
1411 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1412 				return -EINVAL;
1413 
1414 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1415 			mark = 1;
1416 		}
1417 	} else {
1418 		return -EINVAL;
1419 	}
1420 
1421 	read_lock_bh(&idev->lock);
1422 	if (group_type == IPV6_ADDR_ANY) {
1423 		for (ma = idev->mc_list; ma; ma = ma->next) {
1424 			spin_lock_bh(&ma->mca_lock);
1425 			igmp6_group_queried(ma, max_delay);
1426 			spin_unlock_bh(&ma->mca_lock);
1427 		}
1428 	} else {
1429 		for (ma = idev->mc_list; ma; ma = ma->next) {
1430 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1431 				continue;
1432 			spin_lock_bh(&ma->mca_lock);
1433 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1434 				/* gsquery <- gsquery && mark */
1435 				if (!mark)
1436 					ma->mca_flags &= ~MAF_GSQUERY;
1437 			} else {
1438 				/* gsquery <- mark */
1439 				if (mark)
1440 					ma->mca_flags |= MAF_GSQUERY;
1441 				else
1442 					ma->mca_flags &= ~MAF_GSQUERY;
1443 			}
1444 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1445 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1446 				igmp6_group_queried(ma, max_delay);
1447 			spin_unlock_bh(&ma->mca_lock);
1448 			break;
1449 		}
1450 	}
1451 	read_unlock_bh(&idev->lock);
1452 
1453 	return 0;
1454 }
1455 
1456 /* called with rcu_read_lock() */
1457 int igmp6_event_report(struct sk_buff *skb)
1458 {
1459 	struct ifmcaddr6 *ma;
1460 	struct inet6_dev *idev;
1461 	struct mld_msg *mld;
1462 	int addr_type;
1463 
1464 	/* Our own report looped back. Ignore it. */
1465 	if (skb->pkt_type == PACKET_LOOPBACK)
1466 		return 0;
1467 
1468 	/* send our report if the MC router may not have heard this report */
1469 	if (skb->pkt_type != PACKET_MULTICAST &&
1470 	    skb->pkt_type != PACKET_BROADCAST)
1471 		return 0;
1472 
1473 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1474 		return -EINVAL;
1475 
1476 	mld = (struct mld_msg *)icmp6_hdr(skb);
1477 
1478 	/* Drop reports with not link local source */
1479 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1480 	if (addr_type != IPV6_ADDR_ANY &&
1481 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1482 		return -EINVAL;
1483 
1484 	idev = __in6_dev_get(skb->dev);
1485 	if (!idev)
1486 		return -ENODEV;
1487 
1488 	/*
1489 	 *	Cancel the timer for this group
1490 	 */
1491 
1492 	read_lock_bh(&idev->lock);
1493 	for (ma = idev->mc_list; ma; ma = ma->next) {
1494 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1495 			spin_lock(&ma->mca_lock);
1496 			if (del_timer(&ma->mca_timer))
1497 				refcount_dec(&ma->mca_refcnt);
1498 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1499 			spin_unlock(&ma->mca_lock);
1500 			break;
1501 		}
1502 	}
1503 	read_unlock_bh(&idev->lock);
1504 	return 0;
1505 }
1506 
1507 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1508 		  int gdeleted, int sdeleted)
1509 {
1510 	switch (type) {
1511 	case MLD2_MODE_IS_INCLUDE:
1512 	case MLD2_MODE_IS_EXCLUDE:
1513 		if (gdeleted || sdeleted)
1514 			return false;
1515 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1516 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1517 				return true;
1518 			/* don't include if this source is excluded
1519 			 * in all filters
1520 			 */
1521 			if (psf->sf_count[MCAST_INCLUDE])
1522 				return type == MLD2_MODE_IS_INCLUDE;
1523 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1524 				psf->sf_count[MCAST_EXCLUDE];
1525 		}
1526 		return false;
1527 	case MLD2_CHANGE_TO_INCLUDE:
1528 		if (gdeleted || sdeleted)
1529 			return false;
1530 		return psf->sf_count[MCAST_INCLUDE] != 0;
1531 	case MLD2_CHANGE_TO_EXCLUDE:
1532 		if (gdeleted || sdeleted)
1533 			return false;
1534 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1535 		    psf->sf_count[MCAST_INCLUDE])
1536 			return false;
1537 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1538 			psf->sf_count[MCAST_EXCLUDE];
1539 	case MLD2_ALLOW_NEW_SOURCES:
1540 		if (gdeleted || !psf->sf_crcount)
1541 			return false;
1542 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1543 	case MLD2_BLOCK_OLD_SOURCES:
1544 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1545 			return gdeleted || (psf->sf_crcount && sdeleted);
1546 		return psf->sf_crcount && !gdeleted && !sdeleted;
1547 	}
1548 	return false;
1549 }
1550 
1551 static int
1552 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1553 {
1554 	struct ip6_sf_list *psf;
1555 	int scount = 0;
1556 
1557 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1558 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1559 			continue;
1560 		scount++;
1561 	}
1562 	return scount;
1563 }
1564 
1565 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1566 		       struct net_device *dev,
1567 		       const struct in6_addr *saddr,
1568 		       const struct in6_addr *daddr,
1569 		       int proto, int len)
1570 {
1571 	struct ipv6hdr *hdr;
1572 
1573 	skb->protocol = htons(ETH_P_IPV6);
1574 	skb->dev = dev;
1575 
1576 	skb_reset_network_header(skb);
1577 	skb_put(skb, sizeof(struct ipv6hdr));
1578 	hdr = ipv6_hdr(skb);
1579 
1580 	ip6_flow_hdr(hdr, 0, 0);
1581 
1582 	hdr->payload_len = htons(len);
1583 	hdr->nexthdr = proto;
1584 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1585 
1586 	hdr->saddr = *saddr;
1587 	hdr->daddr = *daddr;
1588 }
1589 
1590 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1591 {
1592 	struct net_device *dev = idev->dev;
1593 	struct net *net = dev_net(dev);
1594 	struct sock *sk = net->ipv6.igmp_sk;
1595 	struct sk_buff *skb;
1596 	struct mld2_report *pmr;
1597 	struct in6_addr addr_buf;
1598 	const struct in6_addr *saddr;
1599 	int hlen = LL_RESERVED_SPACE(dev);
1600 	int tlen = dev->needed_tailroom;
1601 	unsigned int size = mtu + hlen + tlen;
1602 	int err;
1603 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1604 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1605 		     IPV6_TLV_PADN, 0 };
1606 
1607 	/* we assume size > sizeof(ra) here */
1608 	/* limit our allocations to order-0 page */
1609 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1610 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1611 
1612 	if (!skb)
1613 		return NULL;
1614 
1615 	skb->priority = TC_PRIO_CONTROL;
1616 	skb_reserve(skb, hlen);
1617 	skb_tailroom_reserve(skb, mtu, tlen);
1618 
1619 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1620 		/* <draft-ietf-magma-mld-source-05.txt>:
1621 		 * use unspecified address as the source address
1622 		 * when a valid link-local address is not available.
1623 		 */
1624 		saddr = &in6addr_any;
1625 	} else
1626 		saddr = &addr_buf;
1627 
1628 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1629 
1630 	skb_put_data(skb, ra, sizeof(ra));
1631 
1632 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1633 	skb_put(skb, sizeof(*pmr));
1634 	pmr = (struct mld2_report *)skb_transport_header(skb);
1635 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1636 	pmr->mld2r_resv1 = 0;
1637 	pmr->mld2r_cksum = 0;
1638 	pmr->mld2r_resv2 = 0;
1639 	pmr->mld2r_ngrec = 0;
1640 	return skb;
1641 }
1642 
1643 static void mld_sendpack(struct sk_buff *skb)
1644 {
1645 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1646 	struct mld2_report *pmr =
1647 			      (struct mld2_report *)skb_transport_header(skb);
1648 	int payload_len, mldlen;
1649 	struct inet6_dev *idev;
1650 	struct net *net = dev_net(skb->dev);
1651 	int err;
1652 	struct flowi6 fl6;
1653 	struct dst_entry *dst;
1654 
1655 	rcu_read_lock();
1656 	idev = __in6_dev_get(skb->dev);
1657 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1658 
1659 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1660 		sizeof(*pip6);
1661 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1662 	pip6->payload_len = htons(payload_len);
1663 
1664 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1665 					   IPPROTO_ICMPV6,
1666 					   csum_partial(skb_transport_header(skb),
1667 							mldlen, 0));
1668 
1669 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1670 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1671 			 skb->dev->ifindex);
1672 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1673 
1674 	err = 0;
1675 	if (IS_ERR(dst)) {
1676 		err = PTR_ERR(dst);
1677 		dst = NULL;
1678 	}
1679 	skb_dst_set(skb, dst);
1680 	if (err)
1681 		goto err_out;
1682 
1683 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1684 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1685 		      dst_output);
1686 out:
1687 	if (!err) {
1688 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1689 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1690 	} else {
1691 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1692 	}
1693 
1694 	rcu_read_unlock();
1695 	return;
1696 
1697 err_out:
1698 	kfree_skb(skb);
1699 	goto out;
1700 }
1701 
1702 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1703 {
1704 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1705 }
1706 
1707 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1708 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1709 {
1710 	struct mld2_report *pmr;
1711 	struct mld2_grec *pgr;
1712 
1713 	if (!skb) {
1714 		skb = mld_newpack(pmc->idev, mtu);
1715 		if (!skb)
1716 			return NULL;
1717 	}
1718 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1719 	pgr->grec_type = type;
1720 	pgr->grec_auxwords = 0;
1721 	pgr->grec_nsrcs = 0;
1722 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1723 	pmr = (struct mld2_report *)skb_transport_header(skb);
1724 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1725 	*ppgr = pgr;
1726 	return skb;
1727 }
1728 
1729 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1730 
1731 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1732 	int type, int gdeleted, int sdeleted, int crsend)
1733 {
1734 	struct inet6_dev *idev = pmc->idev;
1735 	struct net_device *dev = idev->dev;
1736 	struct mld2_report *pmr;
1737 	struct mld2_grec *pgr = NULL;
1738 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1739 	int scount, stotal, first, isquery, truncate;
1740 	unsigned int mtu;
1741 
1742 	if (pmc->mca_flags & MAF_NOREPORT)
1743 		return skb;
1744 
1745 	mtu = READ_ONCE(dev->mtu);
1746 	if (mtu < IPV6_MIN_MTU)
1747 		return skb;
1748 
1749 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1750 		  type == MLD2_MODE_IS_EXCLUDE;
1751 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1752 		    type == MLD2_CHANGE_TO_EXCLUDE;
1753 
1754 	stotal = scount = 0;
1755 
1756 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1757 
1758 	if (!*psf_list)
1759 		goto empty_source;
1760 
1761 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1762 
1763 	/* EX and TO_EX get a fresh packet, if needed */
1764 	if (truncate) {
1765 		if (pmr && pmr->mld2r_ngrec &&
1766 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1767 			if (skb)
1768 				mld_sendpack(skb);
1769 			skb = mld_newpack(idev, mtu);
1770 		}
1771 	}
1772 	first = 1;
1773 	psf_prev = NULL;
1774 	for (psf = *psf_list; psf; psf = psf_next) {
1775 		struct in6_addr *psrc;
1776 
1777 		psf_next = psf->sf_next;
1778 
1779 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1780 			psf_prev = psf;
1781 			continue;
1782 		}
1783 
1784 		/* Based on RFC3810 6.1. Should not send source-list change
1785 		 * records when there is a filter mode change.
1786 		 */
1787 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1788 		     (!gdeleted && pmc->mca_crcount)) &&
1789 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1790 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1791 			goto decrease_sf_crcount;
1792 
1793 		/* clear marks on query responses */
1794 		if (isquery)
1795 			psf->sf_gsresp = 0;
1796 
1797 		if (AVAILABLE(skb) < sizeof(*psrc) +
1798 		    first*sizeof(struct mld2_grec)) {
1799 			if (truncate && !first)
1800 				break;	 /* truncate these */
1801 			if (pgr)
1802 				pgr->grec_nsrcs = htons(scount);
1803 			if (skb)
1804 				mld_sendpack(skb);
1805 			skb = mld_newpack(idev, mtu);
1806 			first = 1;
1807 			scount = 0;
1808 		}
1809 		if (first) {
1810 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1811 			first = 0;
1812 		}
1813 		if (!skb)
1814 			return NULL;
1815 		psrc = skb_put(skb, sizeof(*psrc));
1816 		*psrc = psf->sf_addr;
1817 		scount++; stotal++;
1818 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1819 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1820 decrease_sf_crcount:
1821 			psf->sf_crcount--;
1822 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1823 				if (psf_prev)
1824 					psf_prev->sf_next = psf->sf_next;
1825 				else
1826 					*psf_list = psf->sf_next;
1827 				kfree(psf);
1828 				continue;
1829 			}
1830 		}
1831 		psf_prev = psf;
1832 	}
1833 
1834 empty_source:
1835 	if (!stotal) {
1836 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1837 		    type == MLD2_BLOCK_OLD_SOURCES)
1838 			return skb;
1839 		if (pmc->mca_crcount || isquery || crsend) {
1840 			/* make sure we have room for group header */
1841 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1842 				mld_sendpack(skb);
1843 				skb = NULL; /* add_grhead will get a new one */
1844 			}
1845 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1846 		}
1847 	}
1848 	if (pgr)
1849 		pgr->grec_nsrcs = htons(scount);
1850 
1851 	if (isquery)
1852 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1853 	return skb;
1854 }
1855 
1856 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1857 {
1858 	struct sk_buff *skb = NULL;
1859 	int type;
1860 
1861 	read_lock_bh(&idev->lock);
1862 	if (!pmc) {
1863 		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1864 			if (pmc->mca_flags & MAF_NOREPORT)
1865 				continue;
1866 			spin_lock_bh(&pmc->mca_lock);
1867 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1868 				type = MLD2_MODE_IS_EXCLUDE;
1869 			else
1870 				type = MLD2_MODE_IS_INCLUDE;
1871 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1872 			spin_unlock_bh(&pmc->mca_lock);
1873 		}
1874 	} else {
1875 		spin_lock_bh(&pmc->mca_lock);
1876 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1877 			type = MLD2_MODE_IS_EXCLUDE;
1878 		else
1879 			type = MLD2_MODE_IS_INCLUDE;
1880 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1881 		spin_unlock_bh(&pmc->mca_lock);
1882 	}
1883 	read_unlock_bh(&idev->lock);
1884 	if (skb)
1885 		mld_sendpack(skb);
1886 }
1887 
1888 /*
1889  * remove zero-count source records from a source filter list
1890  */
1891 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1892 {
1893 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1894 
1895 	psf_prev = NULL;
1896 	for (psf = *ppsf; psf; psf = psf_next) {
1897 		psf_next = psf->sf_next;
1898 		if (psf->sf_crcount == 0) {
1899 			if (psf_prev)
1900 				psf_prev->sf_next = psf->sf_next;
1901 			else
1902 				*ppsf = psf->sf_next;
1903 			kfree(psf);
1904 		} else
1905 			psf_prev = psf;
1906 	}
1907 }
1908 
1909 static void mld_send_cr(struct inet6_dev *idev)
1910 {
1911 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1912 	struct sk_buff *skb = NULL;
1913 	int type, dtype;
1914 
1915 	read_lock_bh(&idev->lock);
1916 	spin_lock(&idev->mc_lock);
1917 
1918 	/* deleted MCA's */
1919 	pmc_prev = NULL;
1920 	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
1921 		pmc_next = pmc->next;
1922 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1923 			type = MLD2_BLOCK_OLD_SOURCES;
1924 			dtype = MLD2_BLOCK_OLD_SOURCES;
1925 			skb = add_grec(skb, pmc, type, 1, 0, 0);
1926 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
1927 		}
1928 		if (pmc->mca_crcount) {
1929 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1930 				type = MLD2_CHANGE_TO_INCLUDE;
1931 				skb = add_grec(skb, pmc, type, 1, 0, 0);
1932 			}
1933 			pmc->mca_crcount--;
1934 			if (pmc->mca_crcount == 0) {
1935 				mld_clear_zeros(&pmc->mca_tomb);
1936 				mld_clear_zeros(&pmc->mca_sources);
1937 			}
1938 		}
1939 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1940 		    !pmc->mca_sources) {
1941 			if (pmc_prev)
1942 				pmc_prev->next = pmc_next;
1943 			else
1944 				idev->mc_tomb = pmc_next;
1945 			in6_dev_put(pmc->idev);
1946 			kfree(pmc);
1947 		} else
1948 			pmc_prev = pmc;
1949 	}
1950 	spin_unlock(&idev->mc_lock);
1951 
1952 	/* change recs */
1953 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1954 		spin_lock_bh(&pmc->mca_lock);
1955 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1956 			type = MLD2_BLOCK_OLD_SOURCES;
1957 			dtype = MLD2_ALLOW_NEW_SOURCES;
1958 		} else {
1959 			type = MLD2_ALLOW_NEW_SOURCES;
1960 			dtype = MLD2_BLOCK_OLD_SOURCES;
1961 		}
1962 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1963 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
1964 
1965 		/* filter mode changes */
1966 		if (pmc->mca_crcount) {
1967 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1968 				type = MLD2_CHANGE_TO_EXCLUDE;
1969 			else
1970 				type = MLD2_CHANGE_TO_INCLUDE;
1971 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1972 			pmc->mca_crcount--;
1973 		}
1974 		spin_unlock_bh(&pmc->mca_lock);
1975 	}
1976 	read_unlock_bh(&idev->lock);
1977 	if (!skb)
1978 		return;
1979 	(void) mld_sendpack(skb);
1980 }
1981 
1982 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1983 {
1984 	struct net *net = dev_net(dev);
1985 	struct sock *sk = net->ipv6.igmp_sk;
1986 	struct inet6_dev *idev;
1987 	struct sk_buff *skb;
1988 	struct mld_msg *hdr;
1989 	const struct in6_addr *snd_addr, *saddr;
1990 	struct in6_addr addr_buf;
1991 	int hlen = LL_RESERVED_SPACE(dev);
1992 	int tlen = dev->needed_tailroom;
1993 	int err, len, payload_len, full_len;
1994 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1995 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1996 		     IPV6_TLV_PADN, 0 };
1997 	struct flowi6 fl6;
1998 	struct dst_entry *dst;
1999 
2000 	if (type == ICMPV6_MGM_REDUCTION)
2001 		snd_addr = &in6addr_linklocal_allrouters;
2002 	else
2003 		snd_addr = addr;
2004 
2005 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2006 	payload_len = len + sizeof(ra);
2007 	full_len = sizeof(struct ipv6hdr) + payload_len;
2008 
2009 	rcu_read_lock();
2010 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
2011 		      IPSTATS_MIB_OUT, full_len);
2012 	rcu_read_unlock();
2013 
2014 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
2015 
2016 	if (!skb) {
2017 		rcu_read_lock();
2018 		IP6_INC_STATS(net, __in6_dev_get(dev),
2019 			      IPSTATS_MIB_OUTDISCARDS);
2020 		rcu_read_unlock();
2021 		return;
2022 	}
2023 	skb->priority = TC_PRIO_CONTROL;
2024 	skb_reserve(skb, hlen);
2025 
2026 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2027 		/* <draft-ietf-magma-mld-source-05.txt>:
2028 		 * use unspecified address as the source address
2029 		 * when a valid link-local address is not available.
2030 		 */
2031 		saddr = &in6addr_any;
2032 	} else
2033 		saddr = &addr_buf;
2034 
2035 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2036 
2037 	skb_put_data(skb, ra, sizeof(ra));
2038 
2039 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2040 	hdr->mld_type = type;
2041 	hdr->mld_mca = *addr;
2042 
2043 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2044 					 IPPROTO_ICMPV6,
2045 					 csum_partial(hdr, len, 0));
2046 
2047 	rcu_read_lock();
2048 	idev = __in6_dev_get(skb->dev);
2049 
2050 	icmpv6_flow_init(sk, &fl6, type,
2051 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2052 			 skb->dev->ifindex);
2053 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2054 	if (IS_ERR(dst)) {
2055 		err = PTR_ERR(dst);
2056 		goto err_out;
2057 	}
2058 
2059 	skb_dst_set(skb, dst);
2060 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2061 		      net, sk, skb, NULL, skb->dev,
2062 		      dst_output);
2063 out:
2064 	if (!err) {
2065 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2066 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2067 	} else
2068 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2069 
2070 	rcu_read_unlock();
2071 	return;
2072 
2073 err_out:
2074 	kfree_skb(skb);
2075 	goto out;
2076 }
2077 
2078 static void mld_send_initial_cr(struct inet6_dev *idev)
2079 {
2080 	struct sk_buff *skb;
2081 	struct ifmcaddr6 *pmc;
2082 	int type;
2083 
2084 	if (mld_in_v1_mode(idev))
2085 		return;
2086 
2087 	skb = NULL;
2088 	read_lock_bh(&idev->lock);
2089 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2090 		spin_lock_bh(&pmc->mca_lock);
2091 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2092 			type = MLD2_CHANGE_TO_EXCLUDE;
2093 		else
2094 			type = MLD2_ALLOW_NEW_SOURCES;
2095 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2096 		spin_unlock_bh(&pmc->mca_lock);
2097 	}
2098 	read_unlock_bh(&idev->lock);
2099 	if (skb)
2100 		mld_sendpack(skb);
2101 }
2102 
2103 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2104 {
2105 	idev->mc_dad_count = idev->mc_qrv;
2106 	if (idev->mc_dad_count) {
2107 		mld_send_initial_cr(idev);
2108 		idev->mc_dad_count--;
2109 		if (idev->mc_dad_count)
2110 			mld_dad_start_timer(idev,
2111 					    unsolicited_report_interval(idev));
2112 	}
2113 }
2114 
2115 static void mld_dad_timer_expire(struct timer_list *t)
2116 {
2117 	struct inet6_dev *idev = from_timer(idev, t, mc_dad_timer);
2118 
2119 	mld_send_initial_cr(idev);
2120 	if (idev->mc_dad_count) {
2121 		idev->mc_dad_count--;
2122 		if (idev->mc_dad_count)
2123 			mld_dad_start_timer(idev,
2124 					    unsolicited_report_interval(idev));
2125 	}
2126 	in6_dev_put(idev);
2127 }
2128 
2129 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2130 	const struct in6_addr *psfsrc)
2131 {
2132 	struct ip6_sf_list *psf, *psf_prev;
2133 	int rv = 0;
2134 
2135 	psf_prev = NULL;
2136 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2137 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2138 			break;
2139 		psf_prev = psf;
2140 	}
2141 	if (!psf || psf->sf_count[sfmode] == 0) {
2142 		/* source filter not found, or count wrong =>  bug */
2143 		return -ESRCH;
2144 	}
2145 	psf->sf_count[sfmode]--;
2146 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2147 		struct inet6_dev *idev = pmc->idev;
2148 
2149 		/* no more filters for this source */
2150 		if (psf_prev)
2151 			psf_prev->sf_next = psf->sf_next;
2152 		else
2153 			pmc->mca_sources = psf->sf_next;
2154 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2155 		    !mld_in_v1_mode(idev)) {
2156 			psf->sf_crcount = idev->mc_qrv;
2157 			psf->sf_next = pmc->mca_tomb;
2158 			pmc->mca_tomb = psf;
2159 			rv = 1;
2160 		} else
2161 			kfree(psf);
2162 	}
2163 	return rv;
2164 }
2165 
2166 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2167 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2168 			  int delta)
2169 {
2170 	struct ifmcaddr6 *pmc;
2171 	int	changerec = 0;
2172 	int	i, err;
2173 
2174 	if (!idev)
2175 		return -ENODEV;
2176 	read_lock_bh(&idev->lock);
2177 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2178 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2179 			break;
2180 	}
2181 	if (!pmc) {
2182 		/* MCA not found?? bug */
2183 		read_unlock_bh(&idev->lock);
2184 		return -ESRCH;
2185 	}
2186 	spin_lock_bh(&pmc->mca_lock);
2187 	sf_markstate(pmc);
2188 	if (!delta) {
2189 		if (!pmc->mca_sfcount[sfmode]) {
2190 			spin_unlock_bh(&pmc->mca_lock);
2191 			read_unlock_bh(&idev->lock);
2192 			return -EINVAL;
2193 		}
2194 		pmc->mca_sfcount[sfmode]--;
2195 	}
2196 	err = 0;
2197 	for (i = 0; i < sfcount; i++) {
2198 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2199 
2200 		changerec |= rv > 0;
2201 		if (!err && rv < 0)
2202 			err = rv;
2203 	}
2204 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2205 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2206 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2207 		struct ip6_sf_list *psf;
2208 
2209 		/* filter mode change */
2210 		pmc->mca_sfmode = MCAST_INCLUDE;
2211 		pmc->mca_crcount = idev->mc_qrv;
2212 		idev->mc_ifc_count = pmc->mca_crcount;
2213 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2214 			psf->sf_crcount = 0;
2215 		mld_ifc_event(pmc->idev);
2216 	} else if (sf_setstate(pmc) || changerec)
2217 		mld_ifc_event(pmc->idev);
2218 	spin_unlock_bh(&pmc->mca_lock);
2219 	read_unlock_bh(&idev->lock);
2220 	return err;
2221 }
2222 
2223 /*
2224  * Add multicast single-source filter to the interface list
2225  */
2226 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2227 	const struct in6_addr *psfsrc)
2228 {
2229 	struct ip6_sf_list *psf, *psf_prev;
2230 
2231 	psf_prev = NULL;
2232 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2233 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2234 			break;
2235 		psf_prev = psf;
2236 	}
2237 	if (!psf) {
2238 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2239 		if (!psf)
2240 			return -ENOBUFS;
2241 
2242 		psf->sf_addr = *psfsrc;
2243 		if (psf_prev) {
2244 			psf_prev->sf_next = psf;
2245 		} else
2246 			pmc->mca_sources = psf;
2247 	}
2248 	psf->sf_count[sfmode]++;
2249 	return 0;
2250 }
2251 
2252 static void sf_markstate(struct ifmcaddr6 *pmc)
2253 {
2254 	struct ip6_sf_list *psf;
2255 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2256 
2257 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2258 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2259 			psf->sf_oldin = mca_xcount ==
2260 				psf->sf_count[MCAST_EXCLUDE] &&
2261 				!psf->sf_count[MCAST_INCLUDE];
2262 		} else
2263 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2264 }
2265 
2266 static int sf_setstate(struct ifmcaddr6 *pmc)
2267 {
2268 	struct ip6_sf_list *psf, *dpsf;
2269 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2270 	int qrv = pmc->idev->mc_qrv;
2271 	int new_in, rv;
2272 
2273 	rv = 0;
2274 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2275 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2276 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2277 				!psf->sf_count[MCAST_INCLUDE];
2278 		} else
2279 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2280 		if (new_in) {
2281 			if (!psf->sf_oldin) {
2282 				struct ip6_sf_list *prev = NULL;
2283 
2284 				for (dpsf = pmc->mca_tomb; dpsf;
2285 				     dpsf = dpsf->sf_next) {
2286 					if (ipv6_addr_equal(&dpsf->sf_addr,
2287 					    &psf->sf_addr))
2288 						break;
2289 					prev = dpsf;
2290 				}
2291 				if (dpsf) {
2292 					if (prev)
2293 						prev->sf_next = dpsf->sf_next;
2294 					else
2295 						pmc->mca_tomb = dpsf->sf_next;
2296 					kfree(dpsf);
2297 				}
2298 				psf->sf_crcount = qrv;
2299 				rv++;
2300 			}
2301 		} else if (psf->sf_oldin) {
2302 			psf->sf_crcount = 0;
2303 			/*
2304 			 * add or update "delete" records if an active filter
2305 			 * is now inactive
2306 			 */
2307 			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
2308 				if (ipv6_addr_equal(&dpsf->sf_addr,
2309 				    &psf->sf_addr))
2310 					break;
2311 			if (!dpsf) {
2312 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2313 				if (!dpsf)
2314 					continue;
2315 				*dpsf = *psf;
2316 				/* pmc->mca_lock held by callers */
2317 				dpsf->sf_next = pmc->mca_tomb;
2318 				pmc->mca_tomb = dpsf;
2319 			}
2320 			dpsf->sf_crcount = qrv;
2321 			rv++;
2322 		}
2323 	}
2324 	return rv;
2325 }
2326 
2327 /*
2328  * Add multicast source filter list to the interface list
2329  */
2330 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2331 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2332 			  int delta)
2333 {
2334 	struct ifmcaddr6 *pmc;
2335 	int	isexclude;
2336 	int	i, err;
2337 
2338 	if (!idev)
2339 		return -ENODEV;
2340 	read_lock_bh(&idev->lock);
2341 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2342 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2343 			break;
2344 	}
2345 	if (!pmc) {
2346 		/* MCA not found?? bug */
2347 		read_unlock_bh(&idev->lock);
2348 		return -ESRCH;
2349 	}
2350 	spin_lock_bh(&pmc->mca_lock);
2351 
2352 	sf_markstate(pmc);
2353 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2354 	if (!delta)
2355 		pmc->mca_sfcount[sfmode]++;
2356 	err = 0;
2357 	for (i = 0; i < sfcount; i++) {
2358 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2359 		if (err)
2360 			break;
2361 	}
2362 	if (err) {
2363 		int j;
2364 
2365 		if (!delta)
2366 			pmc->mca_sfcount[sfmode]--;
2367 		for (j = 0; j < i; j++)
2368 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2369 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2370 		struct ip6_sf_list *psf;
2371 
2372 		/* filter mode change */
2373 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2374 			pmc->mca_sfmode = MCAST_EXCLUDE;
2375 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2376 			pmc->mca_sfmode = MCAST_INCLUDE;
2377 		/* else no filters; keep old mode for reports */
2378 
2379 		pmc->mca_crcount = idev->mc_qrv;
2380 		idev->mc_ifc_count = pmc->mca_crcount;
2381 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2382 			psf->sf_crcount = 0;
2383 		mld_ifc_event(idev);
2384 	} else if (sf_setstate(pmc))
2385 		mld_ifc_event(idev);
2386 	spin_unlock_bh(&pmc->mca_lock);
2387 	read_unlock_bh(&idev->lock);
2388 	return err;
2389 }
2390 
2391 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2392 {
2393 	struct ip6_sf_list *psf, *nextpsf;
2394 
2395 	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
2396 		nextpsf = psf->sf_next;
2397 		kfree(psf);
2398 	}
2399 	pmc->mca_tomb = NULL;
2400 	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
2401 		nextpsf = psf->sf_next;
2402 		kfree(psf);
2403 	}
2404 	pmc->mca_sources = NULL;
2405 	pmc->mca_sfmode = MCAST_EXCLUDE;
2406 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2407 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2408 }
2409 
2410 
2411 static void igmp6_join_group(struct ifmcaddr6 *ma)
2412 {
2413 	unsigned long delay;
2414 
2415 	if (ma->mca_flags & MAF_NOREPORT)
2416 		return;
2417 
2418 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2419 
2420 	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
2421 
2422 	spin_lock_bh(&ma->mca_lock);
2423 	if (del_timer(&ma->mca_timer)) {
2424 		refcount_dec(&ma->mca_refcnt);
2425 		delay = ma->mca_timer.expires - jiffies;
2426 	}
2427 
2428 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2429 		refcount_inc(&ma->mca_refcnt);
2430 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2431 	spin_unlock_bh(&ma->mca_lock);
2432 }
2433 
2434 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2435 			    struct inet6_dev *idev)
2436 {
2437 	int err;
2438 
2439 	write_lock_bh(&iml->sflock);
2440 	if (!iml->sflist) {
2441 		/* any-source empty exclude case */
2442 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2443 	} else {
2444 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2445 				iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2446 		sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2447 		iml->sflist = NULL;
2448 	}
2449 	write_unlock_bh(&iml->sflock);
2450 	return err;
2451 }
2452 
2453 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2454 {
2455 	if (mld_in_v1_mode(ma->idev)) {
2456 		if (ma->mca_flags & MAF_LAST_REPORTER)
2457 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2458 				ICMPV6_MGM_REDUCTION);
2459 	} else {
2460 		mld_add_delrec(ma->idev, ma);
2461 		mld_ifc_event(ma->idev);
2462 	}
2463 }
2464 
2465 static void mld_gq_timer_expire(struct timer_list *t)
2466 {
2467 	struct inet6_dev *idev = from_timer(idev, t, mc_gq_timer);
2468 
2469 	idev->mc_gq_running = 0;
2470 	mld_send_report(idev, NULL);
2471 	in6_dev_put(idev);
2472 }
2473 
2474 static void mld_ifc_timer_expire(struct timer_list *t)
2475 {
2476 	struct inet6_dev *idev = from_timer(idev, t, mc_ifc_timer);
2477 
2478 	mld_send_cr(idev);
2479 	if (idev->mc_ifc_count) {
2480 		idev->mc_ifc_count--;
2481 		if (idev->mc_ifc_count)
2482 			mld_ifc_start_timer(idev,
2483 					    unsolicited_report_interval(idev));
2484 	}
2485 	in6_dev_put(idev);
2486 }
2487 
2488 static void mld_ifc_event(struct inet6_dev *idev)
2489 {
2490 	if (mld_in_v1_mode(idev))
2491 		return;
2492 	idev->mc_ifc_count = idev->mc_qrv;
2493 	mld_ifc_start_timer(idev, 1);
2494 }
2495 
2496 static void igmp6_timer_handler(struct timer_list *t)
2497 {
2498 	struct ifmcaddr6 *ma = from_timer(ma, t, mca_timer);
2499 
2500 	if (mld_in_v1_mode(ma->idev))
2501 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2502 	else
2503 		mld_send_report(ma->idev, ma);
2504 
2505 	spin_lock(&ma->mca_lock);
2506 	ma->mca_flags |=  MAF_LAST_REPORTER;
2507 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2508 	spin_unlock(&ma->mca_lock);
2509 	ma_put(ma);
2510 }
2511 
2512 /* Device changing type */
2513 
2514 void ipv6_mc_unmap(struct inet6_dev *idev)
2515 {
2516 	struct ifmcaddr6 *i;
2517 
2518 	/* Install multicast list, except for all-nodes (already installed) */
2519 
2520 	read_lock_bh(&idev->lock);
2521 	for (i = idev->mc_list; i; i = i->next)
2522 		igmp6_group_dropped(i);
2523 	read_unlock_bh(&idev->lock);
2524 }
2525 
2526 void ipv6_mc_remap(struct inet6_dev *idev)
2527 {
2528 	ipv6_mc_up(idev);
2529 }
2530 
2531 /* Device going down */
2532 
2533 void ipv6_mc_down(struct inet6_dev *idev)
2534 {
2535 	struct ifmcaddr6 *i;
2536 
2537 	/* Withdraw multicast list */
2538 
2539 	read_lock_bh(&idev->lock);
2540 
2541 	for (i = idev->mc_list; i; i = i->next)
2542 		igmp6_group_dropped(i);
2543 
2544 	/* Should stop timer after group drop. or we will
2545 	 * start timer again in mld_ifc_event()
2546 	 */
2547 	mld_ifc_stop_timer(idev);
2548 	mld_gq_stop_timer(idev);
2549 	mld_dad_stop_timer(idev);
2550 	read_unlock_bh(&idev->lock);
2551 }
2552 
2553 static void ipv6_mc_reset(struct inet6_dev *idev)
2554 {
2555 	idev->mc_qrv = sysctl_mld_qrv;
2556 	idev->mc_qi = MLD_QI_DEFAULT;
2557 	idev->mc_qri = MLD_QRI_DEFAULT;
2558 	idev->mc_v1_seen = 0;
2559 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2560 }
2561 
2562 /* Device going up */
2563 
2564 void ipv6_mc_up(struct inet6_dev *idev)
2565 {
2566 	struct ifmcaddr6 *i;
2567 
2568 	/* Install multicast list, except for all-nodes (already installed) */
2569 
2570 	read_lock_bh(&idev->lock);
2571 	ipv6_mc_reset(idev);
2572 	for (i = idev->mc_list; i; i = i->next) {
2573 		mld_del_delrec(idev, i);
2574 		igmp6_group_added(i);
2575 	}
2576 	read_unlock_bh(&idev->lock);
2577 }
2578 
2579 /* IPv6 device initialization. */
2580 
2581 void ipv6_mc_init_dev(struct inet6_dev *idev)
2582 {
2583 	write_lock_bh(&idev->lock);
2584 	spin_lock_init(&idev->mc_lock);
2585 	idev->mc_gq_running = 0;
2586 	timer_setup(&idev->mc_gq_timer, mld_gq_timer_expire, 0);
2587 	idev->mc_tomb = NULL;
2588 	idev->mc_ifc_count = 0;
2589 	timer_setup(&idev->mc_ifc_timer, mld_ifc_timer_expire, 0);
2590 	timer_setup(&idev->mc_dad_timer, mld_dad_timer_expire, 0);
2591 	ipv6_mc_reset(idev);
2592 	write_unlock_bh(&idev->lock);
2593 }
2594 
2595 /*
2596  *	Device is about to be destroyed: clean up.
2597  */
2598 
2599 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2600 {
2601 	struct ifmcaddr6 *i;
2602 
2603 	/* Deactivate timers */
2604 	ipv6_mc_down(idev);
2605 	mld_clear_delrec(idev);
2606 
2607 	/* Delete all-nodes address. */
2608 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2609 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2610 	 * fail.
2611 	 */
2612 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2613 
2614 	if (idev->cnf.forwarding)
2615 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2616 
2617 	write_lock_bh(&idev->lock);
2618 	while ((i = idev->mc_list) != NULL) {
2619 		idev->mc_list = i->next;
2620 
2621 		write_unlock_bh(&idev->lock);
2622 		ma_put(i);
2623 		write_lock_bh(&idev->lock);
2624 	}
2625 	write_unlock_bh(&idev->lock);
2626 }
2627 
2628 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2629 {
2630 	struct ifmcaddr6 *pmc;
2631 
2632 	ASSERT_RTNL();
2633 
2634 	if (mld_in_v1_mode(idev)) {
2635 		read_lock_bh(&idev->lock);
2636 		for (pmc = idev->mc_list; pmc; pmc = pmc->next)
2637 			igmp6_join_group(pmc);
2638 		read_unlock_bh(&idev->lock);
2639 	} else
2640 		mld_send_report(idev, NULL);
2641 }
2642 
2643 static int ipv6_mc_netdev_event(struct notifier_block *this,
2644 				unsigned long event,
2645 				void *ptr)
2646 {
2647 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2648 	struct inet6_dev *idev = __in6_dev_get(dev);
2649 
2650 	switch (event) {
2651 	case NETDEV_RESEND_IGMP:
2652 		if (idev)
2653 			ipv6_mc_rejoin_groups(idev);
2654 		break;
2655 	default:
2656 		break;
2657 	}
2658 
2659 	return NOTIFY_DONE;
2660 }
2661 
2662 static struct notifier_block igmp6_netdev_notifier = {
2663 	.notifier_call = ipv6_mc_netdev_event,
2664 };
2665 
2666 #ifdef CONFIG_PROC_FS
2667 struct igmp6_mc_iter_state {
2668 	struct seq_net_private p;
2669 	struct net_device *dev;
2670 	struct inet6_dev *idev;
2671 };
2672 
2673 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2674 
2675 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2676 {
2677 	struct ifmcaddr6 *im = NULL;
2678 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2679 	struct net *net = seq_file_net(seq);
2680 
2681 	state->idev = NULL;
2682 	for_each_netdev_rcu(net, state->dev) {
2683 		struct inet6_dev *idev;
2684 		idev = __in6_dev_get(state->dev);
2685 		if (!idev)
2686 			continue;
2687 		read_lock_bh(&idev->lock);
2688 		im = idev->mc_list;
2689 		if (im) {
2690 			state->idev = idev;
2691 			break;
2692 		}
2693 		read_unlock_bh(&idev->lock);
2694 	}
2695 	return im;
2696 }
2697 
2698 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2699 {
2700 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2701 
2702 	im = im->next;
2703 	while (!im) {
2704 		if (likely(state->idev))
2705 			read_unlock_bh(&state->idev->lock);
2706 
2707 		state->dev = next_net_device_rcu(state->dev);
2708 		if (!state->dev) {
2709 			state->idev = NULL;
2710 			break;
2711 		}
2712 		state->idev = __in6_dev_get(state->dev);
2713 		if (!state->idev)
2714 			continue;
2715 		read_lock_bh(&state->idev->lock);
2716 		im = state->idev->mc_list;
2717 	}
2718 	return im;
2719 }
2720 
2721 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2722 {
2723 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2724 	if (im)
2725 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2726 			--pos;
2727 	return pos ? NULL : im;
2728 }
2729 
2730 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2731 	__acquires(RCU)
2732 {
2733 	rcu_read_lock();
2734 	return igmp6_mc_get_idx(seq, *pos);
2735 }
2736 
2737 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2738 {
2739 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2740 
2741 	++*pos;
2742 	return im;
2743 }
2744 
2745 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2746 	__releases(RCU)
2747 {
2748 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2749 
2750 	if (likely(state->idev)) {
2751 		read_unlock_bh(&state->idev->lock);
2752 		state->idev = NULL;
2753 	}
2754 	state->dev = NULL;
2755 	rcu_read_unlock();
2756 }
2757 
2758 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2759 {
2760 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2761 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2762 
2763 	seq_printf(seq,
2764 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2765 		   state->dev->ifindex, state->dev->name,
2766 		   &im->mca_addr,
2767 		   im->mca_users, im->mca_flags,
2768 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2769 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2770 	return 0;
2771 }
2772 
2773 static const struct seq_operations igmp6_mc_seq_ops = {
2774 	.start	=	igmp6_mc_seq_start,
2775 	.next	=	igmp6_mc_seq_next,
2776 	.stop	=	igmp6_mc_seq_stop,
2777 	.show	=	igmp6_mc_seq_show,
2778 };
2779 
2780 struct igmp6_mcf_iter_state {
2781 	struct seq_net_private p;
2782 	struct net_device *dev;
2783 	struct inet6_dev *idev;
2784 	struct ifmcaddr6 *im;
2785 };
2786 
2787 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2788 
2789 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2790 {
2791 	struct ip6_sf_list *psf = NULL;
2792 	struct ifmcaddr6 *im = NULL;
2793 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2794 	struct net *net = seq_file_net(seq);
2795 
2796 	state->idev = NULL;
2797 	state->im = NULL;
2798 	for_each_netdev_rcu(net, state->dev) {
2799 		struct inet6_dev *idev;
2800 		idev = __in6_dev_get(state->dev);
2801 		if (unlikely(idev == NULL))
2802 			continue;
2803 		read_lock_bh(&idev->lock);
2804 		im = idev->mc_list;
2805 		if (likely(im)) {
2806 			spin_lock_bh(&im->mca_lock);
2807 			psf = im->mca_sources;
2808 			if (likely(psf)) {
2809 				state->im = im;
2810 				state->idev = idev;
2811 				break;
2812 			}
2813 			spin_unlock_bh(&im->mca_lock);
2814 		}
2815 		read_unlock_bh(&idev->lock);
2816 	}
2817 	return psf;
2818 }
2819 
2820 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2821 {
2822 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2823 
2824 	psf = psf->sf_next;
2825 	while (!psf) {
2826 		spin_unlock_bh(&state->im->mca_lock);
2827 		state->im = state->im->next;
2828 		while (!state->im) {
2829 			if (likely(state->idev))
2830 				read_unlock_bh(&state->idev->lock);
2831 
2832 			state->dev = next_net_device_rcu(state->dev);
2833 			if (!state->dev) {
2834 				state->idev = NULL;
2835 				goto out;
2836 			}
2837 			state->idev = __in6_dev_get(state->dev);
2838 			if (!state->idev)
2839 				continue;
2840 			read_lock_bh(&state->idev->lock);
2841 			state->im = state->idev->mc_list;
2842 		}
2843 		if (!state->im)
2844 			break;
2845 		spin_lock_bh(&state->im->mca_lock);
2846 		psf = state->im->mca_sources;
2847 	}
2848 out:
2849 	return psf;
2850 }
2851 
2852 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2853 {
2854 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2855 	if (psf)
2856 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2857 			--pos;
2858 	return pos ? NULL : psf;
2859 }
2860 
2861 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2862 	__acquires(RCU)
2863 {
2864 	rcu_read_lock();
2865 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2866 }
2867 
2868 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2869 {
2870 	struct ip6_sf_list *psf;
2871 	if (v == SEQ_START_TOKEN)
2872 		psf = igmp6_mcf_get_first(seq);
2873 	else
2874 		psf = igmp6_mcf_get_next(seq, v);
2875 	++*pos;
2876 	return psf;
2877 }
2878 
2879 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2880 	__releases(RCU)
2881 {
2882 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2883 	if (likely(state->im)) {
2884 		spin_unlock_bh(&state->im->mca_lock);
2885 		state->im = NULL;
2886 	}
2887 	if (likely(state->idev)) {
2888 		read_unlock_bh(&state->idev->lock);
2889 		state->idev = NULL;
2890 	}
2891 	state->dev = NULL;
2892 	rcu_read_unlock();
2893 }
2894 
2895 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2896 {
2897 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2898 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2899 
2900 	if (v == SEQ_START_TOKEN) {
2901 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
2902 	} else {
2903 		seq_printf(seq,
2904 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2905 			   state->dev->ifindex, state->dev->name,
2906 			   &state->im->mca_addr,
2907 			   &psf->sf_addr,
2908 			   psf->sf_count[MCAST_INCLUDE],
2909 			   psf->sf_count[MCAST_EXCLUDE]);
2910 	}
2911 	return 0;
2912 }
2913 
2914 static const struct seq_operations igmp6_mcf_seq_ops = {
2915 	.start	=	igmp6_mcf_seq_start,
2916 	.next	=	igmp6_mcf_seq_next,
2917 	.stop	=	igmp6_mcf_seq_stop,
2918 	.show	=	igmp6_mcf_seq_show,
2919 };
2920 
2921 static int __net_init igmp6_proc_init(struct net *net)
2922 {
2923 	int err;
2924 
2925 	err = -ENOMEM;
2926 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
2927 			sizeof(struct igmp6_mc_iter_state)))
2928 		goto out;
2929 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
2930 			&igmp6_mcf_seq_ops,
2931 			sizeof(struct igmp6_mcf_iter_state)))
2932 		goto out_proc_net_igmp6;
2933 
2934 	err = 0;
2935 out:
2936 	return err;
2937 
2938 out_proc_net_igmp6:
2939 	remove_proc_entry("igmp6", net->proc_net);
2940 	goto out;
2941 }
2942 
2943 static void __net_exit igmp6_proc_exit(struct net *net)
2944 {
2945 	remove_proc_entry("mcfilter6", net->proc_net);
2946 	remove_proc_entry("igmp6", net->proc_net);
2947 }
2948 #else
2949 static inline int igmp6_proc_init(struct net *net)
2950 {
2951 	return 0;
2952 }
2953 static inline void igmp6_proc_exit(struct net *net)
2954 {
2955 }
2956 #endif
2957 
2958 static int __net_init igmp6_net_init(struct net *net)
2959 {
2960 	int err;
2961 
2962 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2963 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2964 	if (err < 0) {
2965 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2966 		       err);
2967 		goto out;
2968 	}
2969 
2970 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2971 
2972 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
2973 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2974 	if (err < 0) {
2975 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
2976 		       err);
2977 		goto out_sock_create;
2978 	}
2979 
2980 	err = igmp6_proc_init(net);
2981 	if (err)
2982 		goto out_sock_create_autojoin;
2983 
2984 	return 0;
2985 
2986 out_sock_create_autojoin:
2987 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2988 out_sock_create:
2989 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2990 out:
2991 	return err;
2992 }
2993 
2994 static void __net_exit igmp6_net_exit(struct net *net)
2995 {
2996 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2997 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2998 	igmp6_proc_exit(net);
2999 }
3000 
3001 static struct pernet_operations igmp6_net_ops = {
3002 	.init = igmp6_net_init,
3003 	.exit = igmp6_net_exit,
3004 };
3005 
3006 int __init igmp6_init(void)
3007 {
3008 	return register_pernet_subsys(&igmp6_net_ops);
3009 }
3010 
3011 int __init igmp6_late_init(void)
3012 {
3013 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3014 }
3015 
3016 void igmp6_cleanup(void)
3017 {
3018 	unregister_pernet_subsys(&igmp6_net_ops);
3019 }
3020 
3021 void igmp6_late_cleanup(void)
3022 {
3023 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3024 }
3025