xref: /linux/net/ipv6/mcast.c (revision d603517771d8e08a2d8fc9e1f7682ce393d3973a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Multicast support for IPv6
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *
9  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
10  */
11 
12 /* Changes:
13  *
14  *	yoshfuji	: fix format of router-alert option
15  *	YOSHIFUJI Hideaki @USAGI:
16  *		Fixed source address for MLD message based on
17  *		<draft-ietf-magma-mld-source-05.txt>.
18  *	YOSHIFUJI Hideaki @USAGI:
19  *		- Ignore Queries for invalid addresses.
20  *		- MLD for link-local addresses.
21  *	David L Stevens <dlstevens@us.ibm.com>:
22  *		- MLDv2 support
23  */
24 
25 #include <linux/module.h>
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/jiffies.h>
32 #include <linux/net.h>
33 #include <linux/in.h>
34 #include <linux/in6.h>
35 #include <linux/netdevice.h>
36 #include <linux/if_addr.h>
37 #include <linux/if_arp.h>
38 #include <linux/route.h>
39 #include <linux/rtnetlink.h>
40 #include <linux/init.h>
41 #include <linux/proc_fs.h>
42 #include <linux/seq_file.h>
43 #include <linux/slab.h>
44 #include <linux/pkt_sched.h>
45 #include <net/mld.h>
46 #include <linux/workqueue.h>
47 
48 #include <linux/netfilter.h>
49 #include <linux/netfilter_ipv6.h>
50 
51 #include <net/net_namespace.h>
52 #include <net/netlink.h>
53 #include <net/sock.h>
54 #include <net/snmp.h>
55 
56 #include <net/ipv6.h>
57 #include <net/protocol.h>
58 #include <net/if_inet6.h>
59 #include <net/ndisc.h>
60 #include <net/addrconf.h>
61 #include <net/ip6_route.h>
62 #include <net/inet_common.h>
63 
64 #include <net/ip6_checksum.h>
65 
66 /* Ensure that we have struct in6_addr aligned on 32bit word. */
67 static int __mld2_query_bugs[] __attribute__((__unused__)) = {
68 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
69 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
70 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_grec, grec_mca) % 4)
71 };
72 
73 static struct workqueue_struct *mld_wq;
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 mld_mca_work(struct work_struct *work);
79 
80 static void mld_ifc_event(struct inet6_dev *idev);
81 static bool mld_in_v1_mode(const struct inet6_dev *idev);
82 static int sf_setstate(struct ifmcaddr6 *pmc);
83 static void sf_markstate(struct ifmcaddr6 *pmc);
84 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
85 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
86 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
87 			  int delta);
88 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
89 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
90 			  int delta);
91 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
92 			    struct inet6_dev *idev);
93 static int __ipv6_dev_mc_inc(struct net_device *dev,
94 			     const struct in6_addr *addr, unsigned int mode);
95 
96 #define MLD_QRV_DEFAULT		2
97 /* RFC3810, 9.2. Query Interval */
98 #define MLD_QI_DEFAULT		(125 * HZ)
99 /* RFC3810, 9.3. Query Response Interval */
100 #define MLD_QRI_DEFAULT		(10 * HZ)
101 
102 /* RFC3810, 8.1 Query Version Distinctions */
103 #define MLD_V1_QUERY_LEN	24
104 #define MLD_V2_QUERY_LEN_MIN	28
105 
106 #define IPV6_MLD_MAX_MSF	64
107 
108 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
109 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
110 
111 #define mc_assert_locked(idev)			\
112 	lockdep_assert_held(&(idev)->mc_lock)
113 
114 #define mc_dereference(e, idev) \
115 	rcu_dereference_protected(e, lockdep_is_held(&(idev)->mc_lock))
116 
117 #define sock_dereference(e, sk) \
118 	rcu_dereference_protected(e, lockdep_sock_is_held(sk))
119 
120 #define for_each_pmc_socklock(np, sk, pmc)			\
121 	for (pmc = sock_dereference((np)->ipv6_mc_list, sk);	\
122 	     pmc;						\
123 	     pmc = sock_dereference(pmc->next, sk))
124 
125 #define for_each_pmc_rcu(np, pmc)				\
126 	for (pmc = rcu_dereference((np)->ipv6_mc_list);		\
127 	     pmc;						\
128 	     pmc = rcu_dereference(pmc->next))
129 
130 #define for_each_psf_mclock(mc, psf)				\
131 	for (psf = mc_dereference((mc)->mca_sources, mc->idev);	\
132 	     psf;						\
133 	     psf = mc_dereference(psf->sf_next, mc->idev))
134 
135 #define for_each_psf_rcu(mc, psf)				\
136 	for (psf = rcu_dereference((mc)->mca_sources);		\
137 	     psf;						\
138 	     psf = rcu_dereference(psf->sf_next))
139 
140 #define for_each_psf_tomb(mc, psf)				\
141 	for (psf = mc_dereference((mc)->mca_tomb, mc->idev);	\
142 	     psf;						\
143 	     psf = mc_dereference(psf->sf_next, mc->idev))
144 
145 #define for_each_mc_mclock(idev, mc)				\
146 	for (mc = mc_dereference((idev)->mc_list, idev);	\
147 	     mc;						\
148 	     mc = mc_dereference(mc->next, idev))
149 
150 #define for_each_mc_rcu(idev, mc)				\
151 	for (mc = rcu_dereference((idev)->mc_list);             \
152 	     mc;                                                \
153 	     mc = rcu_dereference(mc->next))
154 
155 #define for_each_mc_tomb(idev, mc)				\
156 	for (mc = mc_dereference((idev)->mc_tomb, idev);	\
157 	     mc;						\
158 	     mc = mc_dereference(mc->next, idev))
159 
160 static int unsolicited_report_interval(struct inet6_dev *idev)
161 {
162 	int iv;
163 
164 	if (mld_in_v1_mode(idev))
165 		iv = READ_ONCE(idev->cnf.mldv1_unsolicited_report_interval);
166 	else
167 		iv = READ_ONCE(idev->cnf.mldv2_unsolicited_report_interval);
168 
169 	return iv > 0 ? iv : 1;
170 }
171 
172 static struct net_device *ip6_mc_find_dev(struct net *net,
173 					  const struct in6_addr *group,
174 					  int ifindex)
175 {
176 	struct net_device *dev = NULL;
177 	struct rt6_info *rt;
178 
179 	if (ifindex == 0) {
180 		rcu_read_lock();
181 		rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
182 		if (rt) {
183 			dev = dst_dev_rcu(&rt->dst);
184 			dev_hold(dev);
185 			ip6_rt_put(rt);
186 		}
187 		rcu_read_unlock();
188 	} else {
189 		dev = dev_get_by_index(net, ifindex);
190 	}
191 
192 	return dev;
193 }
194 
195 /*
196  *	socket join on multicast group
197  */
198 static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
199 			       const struct in6_addr *addr, unsigned int mode)
200 {
201 	struct ipv6_pinfo *np = inet6_sk(sk);
202 	struct ipv6_mc_socklist *mc_lst;
203 	struct net *net = sock_net(sk);
204 	struct net_device *dev = NULL;
205 	int err;
206 
207 	if (!ipv6_addr_is_multicast(addr))
208 		return -EINVAL;
209 
210 	for_each_pmc_socklock(np, sk, mc_lst) {
211 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
212 		    ipv6_addr_equal(&mc_lst->addr, addr))
213 			return -EADDRINUSE;
214 	}
215 
216 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
217 	if (!mc_lst)
218 		return -ENOMEM;
219 
220 	mc_lst->next = NULL;
221 	mc_lst->addr = *addr;
222 
223 	dev = ip6_mc_find_dev(net, addr, ifindex);
224 	if (!dev) {
225 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
226 		return -ENODEV;
227 	}
228 
229 	mc_lst->ifindex = dev->ifindex;
230 	mc_lst->sfmode = mode;
231 	RCU_INIT_POINTER(mc_lst->sflist, NULL);
232 
233 	/* now add/increase the group membership on the device */
234 	err = __ipv6_dev_mc_inc(dev, addr, mode);
235 
236 	dev_put(dev);
237 
238 	if (err) {
239 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
240 		return err;
241 	}
242 
243 	mc_lst->next = np->ipv6_mc_list;
244 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
245 
246 	return 0;
247 }
248 
249 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
250 {
251 	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
252 }
253 EXPORT_SYMBOL(ipv6_sock_mc_join);
254 
255 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
256 			  const struct in6_addr *addr, unsigned int mode)
257 {
258 	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
259 }
260 
261 /*
262  *	socket leave on multicast group
263  */
264 static void __ipv6_sock_mc_drop(struct sock *sk, struct ipv6_mc_socklist *mc_lst)
265 {
266 	struct net *net = sock_net(sk);
267 	struct net_device *dev;
268 
269 	dev = dev_get_by_index(net, mc_lst->ifindex);
270 	if (dev) {
271 		struct inet6_dev *idev = in6_dev_get(dev);
272 
273 		ip6_mc_leave_src(sk, mc_lst, idev);
274 
275 		if (idev) {
276 			__ipv6_dev_mc_dec(idev, &mc_lst->addr);
277 			in6_dev_put(idev);
278 		}
279 
280 		dev_put(dev);
281 	} else {
282 		ip6_mc_leave_src(sk, mc_lst, NULL);
283 	}
284 
285 	atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
286 	kfree_rcu(mc_lst, rcu);
287 }
288 
289 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
290 {
291 	struct ipv6_pinfo *np = inet6_sk(sk);
292 	struct ipv6_mc_socklist __rcu **lnk;
293 	struct ipv6_mc_socklist *mc_lst;
294 
295 	if (!ipv6_addr_is_multicast(addr))
296 		return -EINVAL;
297 
298 	for (lnk = &np->ipv6_mc_list;
299 	     (mc_lst = sock_dereference(*lnk, sk)) != NULL;
300 	      lnk = &mc_lst->next) {
301 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
302 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
303 			*lnk = mc_lst->next;
304 			__ipv6_sock_mc_drop(sk, mc_lst);
305 			return 0;
306 		}
307 	}
308 
309 	return -EADDRNOTAVAIL;
310 }
311 EXPORT_SYMBOL(ipv6_sock_mc_drop);
312 
313 static struct inet6_dev *ip6_mc_find_idev(struct net *net,
314 					  const struct in6_addr *group,
315 					  int ifindex)
316 {
317 	struct net_device *dev;
318 	struct inet6_dev *idev;
319 
320 	dev = ip6_mc_find_dev(net, group, ifindex);
321 	if (!dev)
322 		return NULL;
323 
324 	idev = in6_dev_get(dev);
325 	dev_put(dev);
326 
327 	return idev;
328 }
329 
330 void __ipv6_sock_mc_close(struct sock *sk)
331 {
332 	struct ipv6_pinfo *np = inet6_sk(sk);
333 	struct ipv6_mc_socklist *mc_lst;
334 
335 	while ((mc_lst = sock_dereference(np->ipv6_mc_list, sk)) != NULL) {
336 		np->ipv6_mc_list = mc_lst->next;
337 		__ipv6_sock_mc_drop(sk, mc_lst);
338 	}
339 }
340 
341 void ipv6_sock_mc_close(struct sock *sk)
342 {
343 	struct ipv6_pinfo *np = inet6_sk(sk);
344 
345 	if (!rcu_access_pointer(np->ipv6_mc_list))
346 		return;
347 
348 	lock_sock(sk);
349 	__ipv6_sock_mc_close(sk);
350 	release_sock(sk);
351 }
352 
353 int ip6_mc_source(int add, int omode, struct sock *sk,
354 		  struct group_source_req *pgsr)
355 {
356 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
357 	struct in6_addr *source, *group;
358 	struct net *net = sock_net(sk);
359 	struct ipv6_mc_socklist *pmc;
360 	struct ip6_sf_socklist *psl;
361 	struct inet6_dev *idev;
362 	int leavegroup = 0;
363 	int i, j, rv;
364 	int err;
365 
366 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
367 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
368 
369 	if (!ipv6_addr_is_multicast(group))
370 		return -EINVAL;
371 
372 	idev = ip6_mc_find_idev(net, group, pgsr->gsr_interface);
373 	if (!idev)
374 		return -ENODEV;
375 
376 	mutex_lock(&idev->mc_lock);
377 
378 	if (idev->dead) {
379 		err = -ENODEV;
380 		goto done;
381 	}
382 
383 	err = -EADDRNOTAVAIL;
384 
385 	for_each_pmc_socklock(inet6, sk, pmc) {
386 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
387 			continue;
388 		if (ipv6_addr_equal(&pmc->addr, group))
389 			break;
390 	}
391 	if (!pmc) {		/* must have a prior join */
392 		err = -EINVAL;
393 		goto done;
394 	}
395 	/* if a source filter was set, must be the same mode as before */
396 	if (rcu_access_pointer(pmc->sflist)) {
397 		if (pmc->sfmode != omode) {
398 			err = -EINVAL;
399 			goto done;
400 		}
401 	} else if (pmc->sfmode != omode) {
402 		/* allow mode switches for empty-set filters */
403 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
404 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
405 		pmc->sfmode = omode;
406 	}
407 
408 	psl = sock_dereference(pmc->sflist, sk);
409 	if (!add) {
410 		if (!psl)
411 			goto done;	/* err = -EADDRNOTAVAIL */
412 		rv = !0;
413 		for (i = 0; i < psl->sl_count; i++) {
414 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
415 			if (rv == 0)
416 				break;
417 		}
418 		if (rv)		/* source not found */
419 			goto done;	/* err = -EADDRNOTAVAIL */
420 
421 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
422 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
423 			leavegroup = 1;
424 			goto done;
425 		}
426 
427 		/* update the interface filter */
428 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
429 
430 		for (j = i+1; j < psl->sl_count; j++)
431 			psl->sl_addr[j-1] = psl->sl_addr[j];
432 		psl->sl_count--;
433 		err = 0;
434 		goto done;
435 	}
436 	/* else, add a new source to the filter */
437 
438 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
439 		err = -ENOBUFS;
440 		goto done;
441 	}
442 	if (!psl || psl->sl_count == psl->sl_max) {
443 		struct ip6_sf_socklist *newpsl;
444 		int count = IP6_SFBLOCK;
445 
446 		if (psl)
447 			count += psl->sl_max;
448 		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
449 				      GFP_KERNEL);
450 		if (!newpsl) {
451 			err = -ENOBUFS;
452 			goto done;
453 		}
454 		newpsl->sl_max = count;
455 		newpsl->sl_count = count - IP6_SFBLOCK;
456 		if (psl) {
457 			for (i = 0; i < psl->sl_count; i++)
458 				newpsl->sl_addr[i] = psl->sl_addr[i];
459 			atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
460 				   &sk->sk_omem_alloc);
461 		}
462 		rcu_assign_pointer(pmc->sflist, newpsl);
463 		kfree_rcu(psl, rcu);
464 		psl = newpsl;
465 	}
466 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
467 	for (i = 0; i < psl->sl_count; i++) {
468 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
469 		if (rv == 0) /* There is an error in the address. */
470 			goto done;
471 	}
472 	for (j = psl->sl_count-1; j >= i; j--)
473 		psl->sl_addr[j+1] = psl->sl_addr[j];
474 	psl->sl_addr[i] = *source;
475 	psl->sl_count++;
476 	err = 0;
477 	/* update the interface list */
478 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
479 done:
480 	mutex_unlock(&idev->mc_lock);
481 	in6_dev_put(idev);
482 	if (leavegroup)
483 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
484 	return err;
485 }
486 
487 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
488 		    struct sockaddr_storage *list)
489 {
490 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
491 	struct ip6_sf_socklist *newpsl, *psl;
492 	struct net *net = sock_net(sk);
493 	const struct in6_addr *group;
494 	struct ipv6_mc_socklist *pmc;
495 	struct inet6_dev *idev;
496 	int leavegroup = 0;
497 	int i, err;
498 
499 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
500 
501 	if (!ipv6_addr_is_multicast(group))
502 		return -EINVAL;
503 	if (gsf->gf_fmode != MCAST_INCLUDE &&
504 	    gsf->gf_fmode != MCAST_EXCLUDE)
505 		return -EINVAL;
506 
507 	idev = ip6_mc_find_idev(net, group, gsf->gf_interface);
508 	if (!idev)
509 		return -ENODEV;
510 
511 	mutex_lock(&idev->mc_lock);
512 
513 	if (idev->dead) {
514 		err = -ENODEV;
515 		goto done;
516 	}
517 
518 	err = 0;
519 
520 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
521 		leavegroup = 1;
522 		goto done;
523 	}
524 
525 	for_each_pmc_socklock(inet6, sk, pmc) {
526 		if (pmc->ifindex != gsf->gf_interface)
527 			continue;
528 		if (ipv6_addr_equal(&pmc->addr, group))
529 			break;
530 	}
531 	if (!pmc) {		/* must have a prior join */
532 		err = -EINVAL;
533 		goto done;
534 	}
535 	if (gsf->gf_numsrc) {
536 		newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
537 						      gsf->gf_numsrc),
538 				      GFP_KERNEL);
539 		if (!newpsl) {
540 			err = -ENOBUFS;
541 			goto done;
542 		}
543 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
544 		for (i = 0; i < newpsl->sl_count; ++i, ++list) {
545 			struct sockaddr_in6 *psin6;
546 
547 			psin6 = (struct sockaddr_in6 *)list;
548 			newpsl->sl_addr[i] = psin6->sin6_addr;
549 		}
550 
551 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
552 				     newpsl->sl_count, newpsl->sl_addr, 0);
553 		if (err) {
554 			sock_kfree_s(sk, newpsl, struct_size(newpsl, sl_addr,
555 							     newpsl->sl_max));
556 			goto done;
557 		}
558 	} else {
559 		newpsl = NULL;
560 		ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
561 	}
562 
563 	psl = sock_dereference(pmc->sflist, sk);
564 	if (psl) {
565 		ip6_mc_del_src(idev, group, pmc->sfmode,
566 			       psl->sl_count, psl->sl_addr, 0);
567 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
568 			   &sk->sk_omem_alloc);
569 	} else {
570 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
571 	}
572 
573 	rcu_assign_pointer(pmc->sflist, newpsl);
574 	kfree_rcu(psl, rcu);
575 	pmc->sfmode = gsf->gf_fmode;
576 	err = 0;
577 done:
578 	mutex_unlock(&idev->mc_lock);
579 	in6_dev_put(idev);
580 	if (leavegroup)
581 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
582 	return err;
583 }
584 
585 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
586 		  sockptr_t optval, size_t ss_offset)
587 {
588 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
589 	const struct in6_addr *group;
590 	struct ipv6_mc_socklist *pmc;
591 	struct ip6_sf_socklist *psl;
592 	unsigned int count;
593 	int i, copycount;
594 
595 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
596 
597 	if (!ipv6_addr_is_multicast(group))
598 		return -EINVAL;
599 
600 	for_each_pmc_socklock(inet6, sk, pmc) {
601 		if (pmc->ifindex != gsf->gf_interface)
602 			continue;
603 		if (ipv6_addr_equal(group, &pmc->addr))
604 			break;
605 	}
606 	if (!pmc)		/* must have a prior join */
607 		return -EADDRNOTAVAIL;
608 
609 	gsf->gf_fmode = pmc->sfmode;
610 	psl = sock_dereference(pmc->sflist, sk);
611 	count = psl ? psl->sl_count : 0;
612 
613 	copycount = min(count, gsf->gf_numsrc);
614 	gsf->gf_numsrc = count;
615 	for (i = 0; i < copycount; i++) {
616 		struct sockaddr_in6 *psin6;
617 		struct sockaddr_storage ss;
618 
619 		psin6 = (struct sockaddr_in6 *)&ss;
620 		memset(&ss, 0, sizeof(ss));
621 		psin6->sin6_family = AF_INET6;
622 		psin6->sin6_addr = psl->sl_addr[i];
623 		if (copy_to_sockptr_offset(optval, ss_offset, &ss, sizeof(ss)))
624 			return -EFAULT;
625 		ss_offset += sizeof(ss);
626 	}
627 	return 0;
628 }
629 
630 bool inet6_mc_check(const struct sock *sk, const struct in6_addr *mc_addr,
631 		    const struct in6_addr *src_addr)
632 {
633 	const struct ipv6_pinfo *np = inet6_sk(sk);
634 	const struct ipv6_mc_socklist *mc;
635 	const struct ip6_sf_socklist *psl;
636 	bool rv = true;
637 
638 	rcu_read_lock();
639 	for_each_pmc_rcu(np, mc) {
640 		if (ipv6_addr_equal(&mc->addr, mc_addr))
641 			break;
642 	}
643 	if (!mc) {
644 		rcu_read_unlock();
645 		return inet6_test_bit(MC6_ALL, sk);
646 	}
647 	psl = rcu_dereference(mc->sflist);
648 	if (!psl) {
649 		rv = mc->sfmode == MCAST_EXCLUDE;
650 	} else {
651 		int i;
652 
653 		for (i = 0; i < psl->sl_count; i++) {
654 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
655 				break;
656 		}
657 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
658 			rv = false;
659 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
660 			rv = false;
661 	}
662 	rcu_read_unlock();
663 
664 	return rv;
665 }
666 
667 static void igmp6_group_added(struct ifmcaddr6 *mc)
668 {
669 	struct net_device *dev = mc->idev->dev;
670 	char buf[MAX_ADDR_LEN];
671 
672 	mc_assert_locked(mc->idev);
673 
674 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
675 	    IPV6_ADDR_SCOPE_LINKLOCAL)
676 		return;
677 
678 	if (!(mc->mca_flags&MAF_LOADED)) {
679 		mc->mca_flags |= MAF_LOADED;
680 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
681 			dev_mc_add(dev, buf);
682 	}
683 
684 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
685 		return;
686 
687 	if (mld_in_v1_mode(mc->idev)) {
688 		igmp6_join_group(mc);
689 		return;
690 	}
691 	/* else v2 */
692 
693 	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
694 	 * should not send filter-mode change record as the mode
695 	 * should be from IN() to IN(A).
696 	 */
697 	if (mc->mca_sfmode == MCAST_EXCLUDE)
698 		mc->mca_crcount = mc->idev->mc_qrv;
699 
700 	mld_ifc_event(mc->idev);
701 }
702 
703 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
704 {
705 	struct net_device *dev = mc->idev->dev;
706 	char buf[MAX_ADDR_LEN];
707 
708 	mc_assert_locked(mc->idev);
709 
710 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
711 	    IPV6_ADDR_SCOPE_LINKLOCAL)
712 		return;
713 
714 	if (mc->mca_flags&MAF_LOADED) {
715 		mc->mca_flags &= ~MAF_LOADED;
716 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
717 			dev_mc_del(dev, buf);
718 	}
719 
720 	if (mc->mca_flags & MAF_NOREPORT)
721 		return;
722 
723 	if (!mc->idev->dead)
724 		igmp6_leave_group(mc);
725 
726 	if (cancel_delayed_work(&mc->mca_work))
727 		refcount_dec(&mc->mca_refcnt);
728 }
729 
730 /* deleted ifmcaddr6 manipulation */
731 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
732 {
733 	struct ifmcaddr6 *pmc;
734 
735 	mc_assert_locked(idev);
736 
737 	/* this is an "ifmcaddr6" for convenience; only the fields below
738 	 * are actually used. In particular, the refcnt and users are not
739 	 * used for management of the delete list. Using the same structure
740 	 * for deleted items allows change reports to use common code with
741 	 * non-deleted or query-response MCA's.
742 	 */
743 	pmc = kzalloc_obj(*pmc);
744 	if (!pmc)
745 		return;
746 
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 		rcu_assign_pointer(pmc->mca_tomb,
756 				   mc_dereference(im->mca_tomb, idev));
757 		rcu_assign_pointer(pmc->mca_sources,
758 				   mc_dereference(im->mca_sources, idev));
759 		RCU_INIT_POINTER(im->mca_tomb, NULL);
760 		RCU_INIT_POINTER(im->mca_sources, NULL);
761 
762 		for_each_psf_mclock(pmc, psf)
763 			psf->sf_crcount = pmc->mca_crcount;
764 	}
765 
766 	rcu_assign_pointer(pmc->next, idev->mc_tomb);
767 	rcu_assign_pointer(idev->mc_tomb, pmc);
768 }
769 
770 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
771 {
772 	struct ip6_sf_list *psf, *sources, *tomb;
773 	struct in6_addr *pmca = &im->mca_addr;
774 	struct ifmcaddr6 *pmc, *pmc_prev;
775 
776 	mc_assert_locked(idev);
777 
778 	pmc_prev = NULL;
779 	for_each_mc_tomb(idev, pmc) {
780 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
781 			break;
782 		pmc_prev = pmc;
783 	}
784 	if (!pmc)
785 		return;
786 	if (pmc_prev)
787 		rcu_assign_pointer(pmc_prev->next, pmc->next);
788 	else
789 		rcu_assign_pointer(idev->mc_tomb, pmc->next);
790 
791 	im->idev = pmc->idev;
792 	if (im->mca_sfmode == MCAST_INCLUDE) {
793 		tomb = rcu_replace_pointer(im->mca_tomb,
794 					   mc_dereference(pmc->mca_tomb, pmc->idev),
795 					   lockdep_is_held(&im->idev->mc_lock));
796 		rcu_assign_pointer(pmc->mca_tomb, tomb);
797 
798 		sources = rcu_replace_pointer(im->mca_sources,
799 					      mc_dereference(pmc->mca_sources, pmc->idev),
800 					      lockdep_is_held(&im->idev->mc_lock));
801 		rcu_assign_pointer(pmc->mca_sources, sources);
802 		for_each_psf_mclock(im, psf)
803 			psf->sf_crcount = idev->mc_qrv;
804 	} else {
805 		im->mca_crcount = idev->mc_qrv;
806 	}
807 	ip6_mc_clear_src(pmc);
808 	in6_dev_put(pmc->idev);
809 	kfree_rcu(pmc, rcu);
810 }
811 
812 static void mld_clear_delrec(struct inet6_dev *idev)
813 {
814 	struct ifmcaddr6 *pmc, *nextpmc;
815 
816 	mc_assert_locked(idev);
817 
818 	pmc = mc_dereference(idev->mc_tomb, idev);
819 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
820 
821 	for (; pmc; pmc = nextpmc) {
822 		nextpmc = mc_dereference(pmc->next, idev);
823 		ip6_mc_clear_src(pmc);
824 		in6_dev_put(pmc->idev);
825 		kfree_rcu(pmc, rcu);
826 	}
827 
828 	/* clear dead sources, too */
829 	for_each_mc_mclock(idev, pmc) {
830 		struct ip6_sf_list *psf, *psf_next;
831 
832 		psf = mc_dereference(pmc->mca_tomb, idev);
833 		RCU_INIT_POINTER(pmc->mca_tomb, NULL);
834 		for (; psf; psf = psf_next) {
835 			psf_next = mc_dereference(psf->sf_next, idev);
836 			kfree_rcu(psf, rcu);
837 		}
838 	}
839 }
840 
841 static void mld_clear_query(struct inet6_dev *idev)
842 {
843 	spin_lock_bh(&idev->mc_query_lock);
844 	__skb_queue_purge(&idev->mc_query_queue);
845 	spin_unlock_bh(&idev->mc_query_lock);
846 }
847 
848 static void mld_clear_report(struct inet6_dev *idev)
849 {
850 	spin_lock_bh(&idev->mc_report_lock);
851 	__skb_queue_purge(&idev->mc_report_queue);
852 	spin_unlock_bh(&idev->mc_report_lock);
853 }
854 
855 static void ma_put(struct ifmcaddr6 *mc)
856 {
857 	if (refcount_dec_and_test(&mc->mca_refcnt)) {
858 		in6_dev_put(mc->idev);
859 		kfree_rcu(mc, rcu);
860 	}
861 }
862 
863 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
864 				   const struct in6_addr *addr,
865 				   unsigned int mode)
866 {
867 	struct ifmcaddr6 *mc;
868 
869 	mc_assert_locked(idev);
870 
871 	mc = kzalloc_obj(*mc);
872 	if (!mc)
873 		return NULL;
874 
875 	INIT_DELAYED_WORK(&mc->mca_work, mld_mca_work);
876 
877 	mc->mca_addr = *addr;
878 	mc->idev = idev; /* reference taken by caller */
879 	mc->mca_users = 1;
880 	/* mca_stamp should be updated upon changes */
881 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
882 	refcount_set(&mc->mca_refcnt, 1);
883 
884 	mc->mca_sfmode = mode;
885 	mc->mca_sfcount[mode] = 1;
886 
887 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
888 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
889 		mc->mca_flags |= MAF_NOREPORT;
890 
891 	return mc;
892 }
893 
894 static void inet6_ifmcaddr_notify(struct net_device *dev,
895 				  const struct ifmcaddr6 *ifmca, int event)
896 {
897 	struct inet6_fill_args fillargs = {
898 		.portid = 0,
899 		.seq = 0,
900 		.event = event,
901 		.flags = 0,
902 		.netnsid = -1,
903 		.force_rt_scope_universe = true,
904 	};
905 	struct net *net = dev_net(dev);
906 	struct sk_buff *skb;
907 	int err = -ENOMEM;
908 
909 	skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) +
910 			nla_total_size(sizeof(struct in6_addr)) +
911 			nla_total_size(sizeof(struct ifa_cacheinfo)),
912 			GFP_KERNEL);
913 	if (!skb)
914 		goto error;
915 
916 	err = inet6_fill_ifmcaddr(skb, ifmca, &fillargs);
917 	if (err < 0) {
918 		WARN_ON_ONCE(err == -EMSGSIZE);
919 		nlmsg_free(skb);
920 		goto error;
921 	}
922 
923 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MCADDR, NULL, GFP_KERNEL);
924 	return;
925 error:
926 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MCADDR, err);
927 }
928 
929 /*
930  *	device multicast group inc (add if not found)
931  */
932 static int __ipv6_dev_mc_inc(struct net_device *dev,
933 			     const struct in6_addr *addr, unsigned int mode)
934 {
935 	struct inet6_dev *idev;
936 	struct ifmcaddr6 *mc;
937 
938 	/* we need to take a reference on idev */
939 	idev = in6_dev_get(dev);
940 	if (!idev)
941 		return -EINVAL;
942 
943 	mutex_lock(&idev->mc_lock);
944 
945 	if (READ_ONCE(idev->dead)) {
946 		mutex_unlock(&idev->mc_lock);
947 		in6_dev_put(idev);
948 		return -ENODEV;
949 	}
950 
951 	for_each_mc_mclock(idev, mc) {
952 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
953 			mc->mca_users++;
954 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
955 			mutex_unlock(&idev->mc_lock);
956 			in6_dev_put(idev);
957 			return 0;
958 		}
959 	}
960 
961 	mc = mca_alloc(idev, addr, mode);
962 	if (!mc) {
963 		mutex_unlock(&idev->mc_lock);
964 		in6_dev_put(idev);
965 		return -ENOMEM;
966 	}
967 
968 	rcu_assign_pointer(mc->next, idev->mc_list);
969 	rcu_assign_pointer(idev->mc_list, mc);
970 
971 	mld_del_delrec(idev, mc);
972 	igmp6_group_added(mc);
973 	inet6_ifmcaddr_notify(dev, mc, RTM_NEWMULTICAST);
974 	mutex_unlock(&idev->mc_lock);
975 
976 	return 0;
977 }
978 
979 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
980 {
981 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
982 }
983 EXPORT_SYMBOL(ipv6_dev_mc_inc);
984 
985 /*
986  * device multicast group del
987  */
988 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
989 {
990 	struct ifmcaddr6 *ma, __rcu **map;
991 
992 	mutex_lock(&idev->mc_lock);
993 
994 	for (map = &idev->mc_list;
995 	     (ma = mc_dereference(*map, idev));
996 	     map = &ma->next) {
997 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
998 			if (--ma->mca_users == 0) {
999 				*map = ma->next;
1000 
1001 				igmp6_group_dropped(ma);
1002 				inet6_ifmcaddr_notify(idev->dev, ma,
1003 						      RTM_DELMULTICAST);
1004 				ip6_mc_clear_src(ma);
1005 				mutex_unlock(&idev->mc_lock);
1006 
1007 				ma_put(ma);
1008 				return 0;
1009 			}
1010 			mutex_unlock(&idev->mc_lock);
1011 			return 0;
1012 		}
1013 	}
1014 
1015 	mutex_unlock(&idev->mc_lock);
1016 	return -ENOENT;
1017 }
1018 
1019 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
1020 {
1021 	struct inet6_dev *idev;
1022 	int err;
1023 
1024 	idev = in6_dev_get(dev);
1025 	if (!idev)
1026 		return -ENODEV;
1027 
1028 	err = __ipv6_dev_mc_dec(idev, addr);
1029 	in6_dev_put(idev);
1030 
1031 	return err;
1032 }
1033 EXPORT_SYMBOL(ipv6_dev_mc_dec);
1034 
1035 /*
1036  *	check if the interface/address pair is valid
1037  */
1038 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
1039 			 const struct in6_addr *src_addr)
1040 {
1041 	struct inet6_dev *idev;
1042 	struct ifmcaddr6 *mc;
1043 	bool rv = false;
1044 
1045 	rcu_read_lock();
1046 	idev = __in6_dev_get(dev);
1047 	if (!idev)
1048 		goto unlock;
1049 	for_each_mc_rcu(idev, mc) {
1050 		if (ipv6_addr_equal(&mc->mca_addr, group))
1051 			break;
1052 	}
1053 	if (!mc)
1054 		goto unlock;
1055 	if (src_addr && !ipv6_addr_any(src_addr)) {
1056 		struct ip6_sf_list *psf;
1057 
1058 		for_each_psf_rcu(mc, psf) {
1059 			if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1060 				break;
1061 		}
1062 		if (psf)
1063 			rv = READ_ONCE(psf->sf_count[MCAST_INCLUDE]) ||
1064 				READ_ONCE(psf->sf_count[MCAST_EXCLUDE]) !=
1065 				READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]);
1066 		else
1067 			rv = READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]) != 0;
1068 	} else {
1069 		rv = true; /* don't filter unspecified source */
1070 	}
1071 unlock:
1072 	rcu_read_unlock();
1073 	return rv;
1074 }
1075 
1076 static void mld_gq_start_work(struct inet6_dev *idev)
1077 {
1078 	unsigned long tv = get_random_u32_below(idev->mc_maxdelay);
1079 
1080 	mc_assert_locked(idev);
1081 
1082 	idev->mc_gq_running = 1;
1083 	if (!mod_delayed_work(mld_wq, &idev->mc_gq_work, tv + 2))
1084 		in6_dev_hold(idev);
1085 }
1086 
1087 static void mld_gq_stop_work(struct inet6_dev *idev)
1088 {
1089 	mc_assert_locked(idev);
1090 
1091 	idev->mc_gq_running = 0;
1092 	if (cancel_delayed_work(&idev->mc_gq_work))
1093 		__in6_dev_put(idev);
1094 }
1095 
1096 static void mld_ifc_start_work(struct inet6_dev *idev, unsigned long delay)
1097 {
1098 	unsigned long tv = get_random_u32_below(delay);
1099 
1100 	mc_assert_locked(idev);
1101 
1102 	if (!mod_delayed_work(mld_wq, &idev->mc_ifc_work, tv + 2))
1103 		in6_dev_hold(idev);
1104 }
1105 
1106 static void mld_ifc_stop_work(struct inet6_dev *idev)
1107 {
1108 	mc_assert_locked(idev);
1109 
1110 	idev->mc_ifc_count = 0;
1111 	if (cancel_delayed_work(&idev->mc_ifc_work))
1112 		__in6_dev_put(idev);
1113 }
1114 
1115 static void mld_dad_start_work(struct inet6_dev *idev, unsigned long delay)
1116 {
1117 	unsigned long tv = get_random_u32_below(delay);
1118 
1119 	mc_assert_locked(idev);
1120 
1121 	if (!mod_delayed_work(mld_wq, &idev->mc_dad_work, tv + 2))
1122 		in6_dev_hold(idev);
1123 }
1124 
1125 static void mld_dad_stop_work(struct inet6_dev *idev)
1126 {
1127 	if (cancel_delayed_work(&idev->mc_dad_work))
1128 		__in6_dev_put(idev);
1129 }
1130 
1131 static void mld_query_stop_work(struct inet6_dev *idev)
1132 {
1133 	spin_lock_bh(&idev->mc_query_lock);
1134 	if (cancel_delayed_work(&idev->mc_query_work))
1135 		__in6_dev_put(idev);
1136 	spin_unlock_bh(&idev->mc_query_lock);
1137 }
1138 
1139 static void mld_report_stop_work(struct inet6_dev *idev)
1140 {
1141 	if (cancel_delayed_work_sync(&idev->mc_report_work))
1142 		__in6_dev_put(idev);
1143 }
1144 
1145 /* IGMP handling (alias multicast ICMPv6 messages) */
1146 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1147 {
1148 	unsigned long delay = resptime;
1149 
1150 	mc_assert_locked(ma->idev);
1151 
1152 	/* Do not start work for these addresses */
1153 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1154 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1155 		return;
1156 
1157 	if (cancel_delayed_work(&ma->mca_work)) {
1158 		refcount_dec(&ma->mca_refcnt);
1159 		delay = ma->mca_work.timer.expires - jiffies;
1160 	}
1161 
1162 	if (delay >= resptime)
1163 		delay = get_random_u32_below(resptime);
1164 
1165 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
1166 		refcount_inc(&ma->mca_refcnt);
1167 	ma->mca_flags |= MAF_TIMER_RUNNING;
1168 }
1169 
1170 /* mark EXCLUDE-mode sources */
1171 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1172 			     const struct in6_addr *srcs)
1173 {
1174 	struct ip6_sf_list *psf;
1175 	int i, scount;
1176 
1177 	mc_assert_locked(pmc->idev);
1178 
1179 	scount = 0;
1180 	for_each_psf_mclock(pmc, psf) {
1181 		if (scount == nsrcs)
1182 			break;
1183 		for (i = 0; i < nsrcs; i++) {
1184 			/* skip inactive filters */
1185 			if (psf->sf_count[MCAST_INCLUDE] ||
1186 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1187 			    psf->sf_count[MCAST_EXCLUDE])
1188 				break;
1189 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1190 				scount++;
1191 				break;
1192 			}
1193 		}
1194 	}
1195 	pmc->mca_flags &= ~MAF_GSQUERY;
1196 	if (scount == nsrcs)	/* all sources excluded */
1197 		return false;
1198 	return true;
1199 }
1200 
1201 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1202 			    const struct in6_addr *srcs)
1203 {
1204 	struct ip6_sf_list *psf;
1205 	int i, scount;
1206 
1207 	mc_assert_locked(pmc->idev);
1208 
1209 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1210 		return mld_xmarksources(pmc, nsrcs, srcs);
1211 
1212 	/* mark INCLUDE-mode sources */
1213 
1214 	scount = 0;
1215 	for_each_psf_mclock(pmc, psf) {
1216 		if (scount == nsrcs)
1217 			break;
1218 		for (i = 0; i < nsrcs; i++) {
1219 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1220 				psf->sf_gsresp = 1;
1221 				scount++;
1222 				break;
1223 			}
1224 		}
1225 	}
1226 	if (!scount) {
1227 		pmc->mca_flags &= ~MAF_GSQUERY;
1228 		return false;
1229 	}
1230 	pmc->mca_flags |= MAF_GSQUERY;
1231 	return true;
1232 }
1233 
1234 static int mld_force_mld_version(const struct inet6_dev *idev)
1235 {
1236 	const struct net *net = dev_net(idev->dev);
1237 	int all_force;
1238 
1239 	all_force = READ_ONCE(net->ipv6.devconf_all->force_mld_version);
1240 	/* Normally, both are 0 here. If enforcement to a particular is
1241 	 * being used, individual device enforcement will have a lower
1242 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1243 	 */
1244 	return all_force ?: READ_ONCE(idev->cnf.force_mld_version);
1245 }
1246 
1247 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1248 {
1249 	return mld_force_mld_version(idev) == 2;
1250 }
1251 
1252 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1253 {
1254 	return mld_force_mld_version(idev) == 1;
1255 }
1256 
1257 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1258 {
1259 	if (mld_in_v2_mode_only(idev))
1260 		return false;
1261 	if (mld_in_v1_mode_only(idev))
1262 		return true;
1263 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1264 		return true;
1265 
1266 	return false;
1267 }
1268 
1269 static void mld_set_v1_mode(struct inet6_dev *idev)
1270 {
1271 	/* RFC3810, relevant sections:
1272 	 *  - 9.1. Robustness Variable
1273 	 *  - 9.2. Query Interval
1274 	 *  - 9.3. Query Response Interval
1275 	 *  - 9.12. Older Version Querier Present Timeout
1276 	 */
1277 	unsigned long switchback;
1278 
1279 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1280 
1281 	idev->mc_v1_seen = jiffies + switchback;
1282 }
1283 
1284 static void mld_update_qrv(struct inet6_dev *idev,
1285 			   const struct mld2_query *mlh2)
1286 {
1287 	/* RFC3810, relevant sections:
1288 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1289 	 *  - 9.1. Robustness Variable
1290 	 */
1291 
1292 	/* The value of the Robustness Variable MUST NOT be zero,
1293 	 * and SHOULD NOT be one. Catch this here if we ever run
1294 	 * into such a case in future.
1295 	 */
1296 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1297 	WARN_ON(idev->mc_qrv == 0);
1298 
1299 	if (mlh2->mld2q_qrv > 0)
1300 		idev->mc_qrv = mlh2->mld2q_qrv;
1301 
1302 	if (unlikely(idev->mc_qrv < min_qrv)) {
1303 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1304 				     idev->mc_qrv, min_qrv);
1305 		idev->mc_qrv = min_qrv;
1306 	}
1307 }
1308 
1309 static void mld_update_qi(struct inet6_dev *idev,
1310 			  const struct mld2_query *mlh2)
1311 {
1312 	/* RFC3810, relevant sections:
1313 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1314 	 *  - 9.2. Query Interval
1315 	 *  - 9.12. Older Version Querier Present Timeout
1316 	 *    (the [Query Interval] in the last Query received)
1317 	 */
1318 	idev->mc_qi = mldv2_qqi(mlh2) * HZ;
1319 }
1320 
1321 static void mld_update_qri(struct inet6_dev *idev,
1322 			   const struct mld2_query *mlh2)
1323 {
1324 	/* RFC3810, relevant sections:
1325 	 *  - 5.1.3. Maximum Response Code
1326 	 *  - 9.3. Query Response Interval
1327 	 */
1328 	idev->mc_qri = msecs_to_jiffies(mldv2_mrd(mlh2));
1329 }
1330 
1331 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1332 			  unsigned long *max_delay, bool v1_query)
1333 {
1334 	unsigned long mldv1_md;
1335 
1336 	/* Ignore v1 queries */
1337 	if (mld_in_v2_mode_only(idev))
1338 		return -EINVAL;
1339 
1340 	mldv1_md = ntohs(mld->mld_maxdelay);
1341 
1342 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1343 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1344 	 * only works when the exponential algorithm is not being
1345 	 * used (as MLDv1 is unaware of such things).
1346 	 *
1347 	 * According to the RFC author, the MLDv2 implementations
1348 	 * he's aware of all use a MRC < 32768 on start up queries.
1349 	 *
1350 	 * Thus, should we *ever* encounter something else larger
1351 	 * than that, just assume the maximum possible within our
1352 	 * reach.
1353 	 */
1354 	if (!v1_query)
1355 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1356 
1357 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1358 
1359 	/* MLDv1 router present: we need to go into v1 mode *only*
1360 	 * when an MLDv1 query is received as per section 9.12. of
1361 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1362 	 * queries MUST be of exactly 24 octets.
1363 	 */
1364 	if (v1_query)
1365 		mld_set_v1_mode(idev);
1366 
1367 	/* cancel MLDv2 report work */
1368 	mld_gq_stop_work(idev);
1369 	/* cancel the interface change work */
1370 	mld_ifc_stop_work(idev);
1371 	/* clear deleted report items */
1372 	mld_clear_delrec(idev);
1373 
1374 	return 0;
1375 }
1376 
1377 static void mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1378 			   unsigned long *max_delay)
1379 {
1380 	*max_delay = max(msecs_to_jiffies(mldv2_mrd(mld)), 1UL);
1381 
1382 	mld_update_qrv(idev, mld);
1383 	mld_update_qi(idev, mld);
1384 	mld_update_qri(idev, mld);
1385 
1386 	idev->mc_maxdelay = *max_delay;
1387 
1388 	return;
1389 }
1390 
1391 /* called with rcu_read_lock() */
1392 void igmp6_event_query(struct sk_buff *skb)
1393 {
1394 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1395 
1396 	if (!idev || idev->dead)
1397 		goto out;
1398 
1399 	spin_lock_bh(&idev->mc_query_lock);
1400 	if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS) {
1401 		__skb_queue_tail(&idev->mc_query_queue, skb);
1402 		if (!mod_delayed_work(mld_wq, &idev->mc_query_work, 0))
1403 			in6_dev_hold(idev);
1404 		skb = NULL;
1405 	}
1406 	spin_unlock_bh(&idev->mc_query_lock);
1407 out:
1408 	kfree_skb(skb);
1409 }
1410 
1411 static void __mld_query_work(struct sk_buff *skb)
1412 {
1413 	struct mld2_query *mlh2 = NULL;
1414 	const struct in6_addr *group;
1415 	unsigned long max_delay;
1416 	struct inet6_dev *idev;
1417 	struct ifmcaddr6 *ma;
1418 	struct mld_msg *mld;
1419 	int group_type;
1420 	int mark = 0;
1421 	int len, err;
1422 
1423 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1424 		goto kfree_skb;
1425 
1426 	/* compute payload length excluding extension headers */
1427 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1428 	len -= skb_network_header_len(skb);
1429 
1430 	/* RFC3810 6.2
1431 	 * Upon reception of an MLD message that contains a Query, the node
1432 	 * checks if the source address of the message is a valid link-local
1433 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1434 	 * option is present in the Hop-By-Hop Options header of the IPv6
1435 	 * packet.  If any of these checks fails, the packet is dropped.
1436 	 */
1437 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1438 	    ipv6_hdr(skb)->hop_limit != 1 ||
1439 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1440 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1441 		goto kfree_skb;
1442 
1443 	idev = in6_dev_get(skb->dev);
1444 	if (!idev)
1445 		goto kfree_skb;
1446 
1447 	mld = (struct mld_msg *)icmp6_hdr(skb);
1448 	group = &mld->mld_mca;
1449 	group_type = ipv6_addr_type(group);
1450 
1451 	if (group_type != IPV6_ADDR_ANY &&
1452 	    !(group_type&IPV6_ADDR_MULTICAST))
1453 		goto out;
1454 
1455 	if (len < MLD_V1_QUERY_LEN) {
1456 		goto out;
1457 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1458 		err = mld_process_v1(idev, mld, &max_delay,
1459 				     len == MLD_V1_QUERY_LEN);
1460 		if (err < 0)
1461 			goto out;
1462 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1463 		int srcs_offset = sizeof(struct mld2_query) -
1464 				  sizeof(struct icmp6hdr);
1465 
1466 		if (!pskb_may_pull(skb, srcs_offset))
1467 			goto out;
1468 
1469 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1470 
1471 		mld_process_v2(idev, mlh2, &max_delay);
1472 
1473 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1474 			if (mlh2->mld2q_nsrcs)
1475 				goto out; /* no sources allowed */
1476 
1477 			mld_gq_start_work(idev);
1478 			goto out;
1479 		}
1480 		/* mark sources to include, if group & source-specific */
1481 		if (mlh2->mld2q_nsrcs != 0) {
1482 			if (!pskb_may_pull(skb, srcs_offset +
1483 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1484 				goto out;
1485 
1486 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1487 			mark = 1;
1488 		}
1489 	} else {
1490 		goto out;
1491 	}
1492 
1493 	if (group_type == IPV6_ADDR_ANY) {
1494 		for_each_mc_mclock(idev, ma) {
1495 			igmp6_group_queried(ma, max_delay);
1496 		}
1497 	} else {
1498 		for_each_mc_mclock(idev, ma) {
1499 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1500 				continue;
1501 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1502 				/* gsquery <- gsquery && mark */
1503 				if (!mark)
1504 					ma->mca_flags &= ~MAF_GSQUERY;
1505 			} else {
1506 				/* gsquery <- mark */
1507 				if (mark)
1508 					ma->mca_flags |= MAF_GSQUERY;
1509 				else
1510 					ma->mca_flags &= ~MAF_GSQUERY;
1511 			}
1512 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1513 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1514 				igmp6_group_queried(ma, max_delay);
1515 			break;
1516 		}
1517 	}
1518 
1519 out:
1520 	in6_dev_put(idev);
1521 kfree_skb:
1522 	consume_skb(skb);
1523 }
1524 
1525 static void mld_query_work(struct work_struct *work)
1526 {
1527 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1528 					      struct inet6_dev,
1529 					      mc_query_work);
1530 	struct sk_buff_head q;
1531 	struct sk_buff *skb;
1532 	bool rework = false;
1533 	int cnt = 0;
1534 
1535 	skb_queue_head_init(&q);
1536 
1537 	spin_lock_bh(&idev->mc_query_lock);
1538 	while ((skb = __skb_dequeue(&idev->mc_query_queue))) {
1539 		__skb_queue_tail(&q, skb);
1540 
1541 		if (++cnt >= MLD_MAX_QUEUE) {
1542 			rework = true;
1543 			break;
1544 		}
1545 	}
1546 	spin_unlock_bh(&idev->mc_query_lock);
1547 
1548 	mutex_lock(&idev->mc_lock);
1549 	while ((skb = __skb_dequeue(&q)))
1550 		__mld_query_work(skb);
1551 	mutex_unlock(&idev->mc_lock);
1552 
1553 	if (rework && queue_delayed_work(mld_wq, &idev->mc_query_work, 0))
1554 		return;
1555 
1556 	in6_dev_put(idev);
1557 }
1558 
1559 /* called with rcu_read_lock() */
1560 void igmp6_event_report(struct sk_buff *skb)
1561 {
1562 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1563 
1564 	if (!idev || idev->dead)
1565 		goto out;
1566 
1567 	spin_lock_bh(&idev->mc_report_lock);
1568 	if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS) {
1569 		__skb_queue_tail(&idev->mc_report_queue, skb);
1570 		if (!mod_delayed_work(mld_wq, &idev->mc_report_work, 0))
1571 			in6_dev_hold(idev);
1572 		skb = NULL;
1573 	}
1574 	spin_unlock_bh(&idev->mc_report_lock);
1575 out:
1576 	kfree_skb(skb);
1577 }
1578 
1579 static void __mld_report_work(struct sk_buff *skb)
1580 {
1581 	struct inet6_dev *idev;
1582 	struct ifmcaddr6 *ma;
1583 	struct mld_msg *mld;
1584 	int addr_type;
1585 
1586 	/* Our own report looped back. Ignore it. */
1587 	if (skb->pkt_type == PACKET_LOOPBACK)
1588 		goto kfree_skb;
1589 
1590 	/* send our report if the MC router may not have heard this report */
1591 	if (skb->pkt_type != PACKET_MULTICAST &&
1592 	    skb->pkt_type != PACKET_BROADCAST)
1593 		goto kfree_skb;
1594 
1595 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1596 		goto kfree_skb;
1597 
1598 	mld = (struct mld_msg *)icmp6_hdr(skb);
1599 
1600 	/* Drop reports with not link local source */
1601 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1602 	if (addr_type != IPV6_ADDR_ANY &&
1603 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1604 		goto kfree_skb;
1605 
1606 	idev = in6_dev_get(skb->dev);
1607 	if (!idev)
1608 		goto kfree_skb;
1609 
1610 	/*
1611 	 *	Cancel the work for this group
1612 	 */
1613 
1614 	for_each_mc_mclock(idev, ma) {
1615 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1616 			if (cancel_delayed_work(&ma->mca_work))
1617 				refcount_dec(&ma->mca_refcnt);
1618 			ma->mca_flags &= ~(MAF_LAST_REPORTER |
1619 					   MAF_TIMER_RUNNING);
1620 			break;
1621 		}
1622 	}
1623 
1624 	in6_dev_put(idev);
1625 kfree_skb:
1626 	consume_skb(skb);
1627 }
1628 
1629 static void mld_report_work(struct work_struct *work)
1630 {
1631 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1632 					      struct inet6_dev,
1633 					      mc_report_work);
1634 	struct sk_buff_head q;
1635 	struct sk_buff *skb;
1636 	bool rework = false;
1637 	int cnt = 0;
1638 
1639 	skb_queue_head_init(&q);
1640 	spin_lock_bh(&idev->mc_report_lock);
1641 	while ((skb = __skb_dequeue(&idev->mc_report_queue))) {
1642 		__skb_queue_tail(&q, skb);
1643 
1644 		if (++cnt >= MLD_MAX_QUEUE) {
1645 			rework = true;
1646 			break;
1647 		}
1648 	}
1649 	spin_unlock_bh(&idev->mc_report_lock);
1650 
1651 	mutex_lock(&idev->mc_lock);
1652 	while ((skb = __skb_dequeue(&q)))
1653 		__mld_report_work(skb);
1654 	mutex_unlock(&idev->mc_lock);
1655 
1656 	if (rework && queue_delayed_work(mld_wq, &idev->mc_report_work, 0))
1657 		return;
1658 
1659 	in6_dev_put(idev);
1660 }
1661 
1662 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1663 		  int gdeleted, int sdeleted)
1664 {
1665 	switch (type) {
1666 	case MLD2_MODE_IS_INCLUDE:
1667 	case MLD2_MODE_IS_EXCLUDE:
1668 		if (gdeleted || sdeleted)
1669 			return false;
1670 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1671 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1672 				return true;
1673 			/* don't include if this source is excluded
1674 			 * in all filters
1675 			 */
1676 			if (psf->sf_count[MCAST_INCLUDE])
1677 				return type == MLD2_MODE_IS_INCLUDE;
1678 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1679 				psf->sf_count[MCAST_EXCLUDE];
1680 		}
1681 		return false;
1682 	case MLD2_CHANGE_TO_INCLUDE:
1683 		if (gdeleted || sdeleted)
1684 			return false;
1685 		return psf->sf_count[MCAST_INCLUDE] != 0;
1686 	case MLD2_CHANGE_TO_EXCLUDE:
1687 		if (gdeleted || sdeleted)
1688 			return false;
1689 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1690 		    psf->sf_count[MCAST_INCLUDE])
1691 			return false;
1692 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1693 			psf->sf_count[MCAST_EXCLUDE];
1694 	case MLD2_ALLOW_NEW_SOURCES:
1695 		if (gdeleted || !psf->sf_crcount)
1696 			return false;
1697 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1698 	case MLD2_BLOCK_OLD_SOURCES:
1699 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1700 			return gdeleted || (psf->sf_crcount && sdeleted);
1701 		return psf->sf_crcount && !gdeleted && !sdeleted;
1702 	}
1703 	return false;
1704 }
1705 
1706 static int
1707 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1708 {
1709 	struct ip6_sf_list *psf;
1710 	int scount = 0;
1711 
1712 	for_each_psf_mclock(pmc, psf) {
1713 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1714 			continue;
1715 		scount++;
1716 	}
1717 	return scount;
1718 }
1719 
1720 static void ip6_mc_hdr(const struct sock *sk, struct sk_buff *skb,
1721 		       struct net_device *dev, const struct in6_addr *saddr,
1722 		       const struct in6_addr *daddr, int proto, int len)
1723 {
1724 	struct ipv6hdr *hdr;
1725 
1726 	skb->protocol = htons(ETH_P_IPV6);
1727 	skb->dev = dev;
1728 
1729 	skb_reset_network_header(skb);
1730 	skb_put(skb, sizeof(struct ipv6hdr));
1731 	hdr = ipv6_hdr(skb);
1732 
1733 	ip6_flow_hdr(hdr, 0, 0);
1734 
1735 	hdr->payload_len = htons(len);
1736 	hdr->nexthdr = proto;
1737 	hdr->hop_limit = READ_ONCE(inet6_sk(sk)->hop_limit);
1738 
1739 	hdr->saddr = *saddr;
1740 	hdr->daddr = *daddr;
1741 }
1742 
1743 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1744 {
1745 	u8 ra[8] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT,
1746 		     2, 0, 0, IPV6_TLV_PADN, 0 };
1747 	struct net_device *dev = idev->dev;
1748 	int hlen = LL_RESERVED_SPACE(dev);
1749 	int tlen = dev->needed_tailroom;
1750 	const struct in6_addr *saddr;
1751 	struct in6_addr addr_buf;
1752 	struct mld2_report *pmr;
1753 	struct sk_buff *skb;
1754 	unsigned int size;
1755 	struct sock *sk;
1756 	struct net *net;
1757 
1758 	/* we assume size > sizeof(ra) here
1759 	 * Also try to not allocate high-order pages for big MTU
1760 	 */
1761 	size = min_t(int, mtu, PAGE_SIZE / 2) + hlen + tlen;
1762 	skb = alloc_skb(size, GFP_KERNEL);
1763 	if (!skb)
1764 		return NULL;
1765 
1766 	skb->priority = TC_PRIO_CONTROL;
1767 	skb_reserve(skb, hlen);
1768 	skb_tailroom_reserve(skb, mtu, tlen);
1769 
1770 	rcu_read_lock();
1771 
1772 	net = dev_net_rcu(dev);
1773 	sk = net->ipv6.igmp_sk;
1774 	skb_set_owner_w(skb, sk);
1775 
1776 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1777 		/* <draft-ietf-magma-mld-source-05.txt>:
1778 		 * use unspecified address as the source address
1779 		 * when a valid link-local address is not available.
1780 		 */
1781 		saddr = &in6addr_any;
1782 	} else
1783 		saddr = &addr_buf;
1784 
1785 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1786 
1787 	rcu_read_unlock();
1788 
1789 	skb_put_data(skb, ra, sizeof(ra));
1790 
1791 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1792 	skb_put(skb, sizeof(*pmr));
1793 	pmr = (struct mld2_report *)skb_transport_header(skb);
1794 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1795 	pmr->mld2r_resv1 = 0;
1796 	pmr->mld2r_cksum = 0;
1797 	pmr->mld2r_resv2 = 0;
1798 	pmr->mld2r_ngrec = 0;
1799 	return skb;
1800 }
1801 
1802 static void mld_sendpack(struct sk_buff *skb)
1803 {
1804 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1805 	struct mld2_report *pmr =
1806 			      (struct mld2_report *)skb_transport_header(skb);
1807 	int payload_len, mldlen;
1808 	struct inet6_dev *idev;
1809 	struct net *net = dev_net(skb->dev);
1810 	int err;
1811 	struct flowi6 fl6;
1812 	struct dst_entry *dst;
1813 
1814 	rcu_read_lock();
1815 	idev = __in6_dev_get(skb->dev);
1816 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
1817 
1818 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1819 		sizeof(*pip6);
1820 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1821 	pip6->payload_len = htons(payload_len);
1822 
1823 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1824 					   IPPROTO_ICMPV6,
1825 					   csum_partial(skb_transport_header(skb),
1826 							mldlen, 0));
1827 
1828 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1829 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1830 			 skb->dev->ifindex);
1831 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1832 
1833 	err = 0;
1834 	if (IS_ERR(dst)) {
1835 		err = PTR_ERR(dst);
1836 		dst = NULL;
1837 	}
1838 	skb_dst_set(skb, dst);
1839 	if (err)
1840 		goto err_out;
1841 
1842 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1843 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1844 		      dst_output);
1845 out:
1846 	if (!err) {
1847 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1848 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1849 	} else {
1850 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1851 	}
1852 
1853 	rcu_read_unlock();
1854 	return;
1855 
1856 err_out:
1857 	kfree_skb(skb);
1858 	goto out;
1859 }
1860 
1861 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1862 {
1863 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1864 }
1865 
1866 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1867 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1868 {
1869 	struct mld2_report *pmr;
1870 	struct mld2_grec *pgr;
1871 
1872 	if (!skb) {
1873 		skb = mld_newpack(pmc->idev, mtu);
1874 		if (!skb)
1875 			return NULL;
1876 	}
1877 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1878 	pgr->grec_type = type;
1879 	pgr->grec_auxwords = 0;
1880 	pgr->grec_nsrcs = 0;
1881 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1882 	pmr = (struct mld2_report *)skb_transport_header(skb);
1883 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1884 	*ppgr = pgr;
1885 	return skb;
1886 }
1887 
1888 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1889 
1890 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1891 				int type, int gdeleted, int sdeleted,
1892 				int crsend)
1893 {
1894 	struct ip6_sf_list *psf, *psf_prev, *psf_next;
1895 	int scount, stotal, first, isquery, truncate;
1896 	struct ip6_sf_list __rcu **psf_list;
1897 	struct inet6_dev *idev = pmc->idev;
1898 	struct net_device *dev = idev->dev;
1899 	struct mld2_grec *pgr = NULL;
1900 	struct mld2_report *pmr;
1901 	unsigned int mtu;
1902 
1903 	mc_assert_locked(idev);
1904 
1905 	if (pmc->mca_flags & MAF_NOREPORT)
1906 		return skb;
1907 
1908 	mtu = READ_ONCE(dev->mtu);
1909 	if (mtu < IPV6_MIN_MTU)
1910 		return skb;
1911 
1912 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1913 		  type == MLD2_MODE_IS_EXCLUDE;
1914 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1915 		    type == MLD2_CHANGE_TO_EXCLUDE;
1916 
1917 	stotal = scount = 0;
1918 
1919 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1920 
1921 	if (!rcu_access_pointer(*psf_list))
1922 		goto empty_source;
1923 
1924 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1925 
1926 	/* EX and TO_EX get a fresh packet, if needed */
1927 	if (truncate) {
1928 		if (pmr && pmr->mld2r_ngrec &&
1929 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1930 			if (skb)
1931 				mld_sendpack(skb);
1932 			skb = mld_newpack(idev, mtu);
1933 		}
1934 	}
1935 	first = 1;
1936 	psf_prev = NULL;
1937 	for (psf = mc_dereference(*psf_list, idev);
1938 	     psf;
1939 	     psf = psf_next) {
1940 		struct in6_addr *psrc;
1941 
1942 		psf_next = mc_dereference(psf->sf_next, idev);
1943 
1944 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1945 			psf_prev = psf;
1946 			continue;
1947 		}
1948 
1949 		/* Based on RFC3810 6.1. Should not send source-list change
1950 		 * records when there is a filter mode change.
1951 		 */
1952 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1953 		     (!gdeleted && pmc->mca_crcount)) &&
1954 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1955 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1956 			goto decrease_sf_crcount;
1957 
1958 		/* clear marks on query responses */
1959 		if (isquery)
1960 			psf->sf_gsresp = 0;
1961 
1962 		if (AVAILABLE(skb) < sizeof(*psrc) +
1963 		    first*sizeof(struct mld2_grec)) {
1964 			if (truncate && !first)
1965 				break;	 /* truncate these */
1966 			if (pgr)
1967 				pgr->grec_nsrcs = htons(scount);
1968 			if (skb)
1969 				mld_sendpack(skb);
1970 			skb = mld_newpack(idev, mtu);
1971 			first = 1;
1972 			scount = 0;
1973 		}
1974 		if (first) {
1975 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1976 			first = 0;
1977 		}
1978 		if (!skb)
1979 			return NULL;
1980 		psrc = skb_put(skb, sizeof(*psrc));
1981 		*psrc = psf->sf_addr;
1982 		scount++; stotal++;
1983 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1984 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1985 decrease_sf_crcount:
1986 			psf->sf_crcount--;
1987 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1988 				if (psf_prev)
1989 					rcu_assign_pointer(psf_prev->sf_next,
1990 							   mc_dereference(psf->sf_next, idev));
1991 				else
1992 					rcu_assign_pointer(*psf_list,
1993 							   mc_dereference(psf->sf_next, idev));
1994 				kfree_rcu(psf, rcu);
1995 				continue;
1996 			}
1997 		}
1998 		psf_prev = psf;
1999 	}
2000 
2001 empty_source:
2002 	if (!stotal) {
2003 		if (type == MLD2_ALLOW_NEW_SOURCES ||
2004 		    type == MLD2_BLOCK_OLD_SOURCES)
2005 			return skb;
2006 		if (pmc->mca_crcount || isquery || crsend) {
2007 			/* make sure we have room for group header */
2008 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
2009 				mld_sendpack(skb);
2010 				skb = NULL; /* add_grhead will get a new one */
2011 			}
2012 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
2013 		}
2014 	}
2015 	if (pgr)
2016 		pgr->grec_nsrcs = htons(scount);
2017 
2018 	if (isquery)
2019 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
2020 	return skb;
2021 }
2022 
2023 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
2024 {
2025 	struct sk_buff *skb = NULL;
2026 	int type;
2027 
2028 	mc_assert_locked(idev);
2029 
2030 	if (!pmc) {
2031 		for_each_mc_mclock(idev, pmc) {
2032 			if (pmc->mca_flags & MAF_NOREPORT)
2033 				continue;
2034 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
2035 				type = MLD2_MODE_IS_EXCLUDE;
2036 			else
2037 				type = MLD2_MODE_IS_INCLUDE;
2038 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2039 		}
2040 	} else {
2041 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2042 			type = MLD2_MODE_IS_EXCLUDE;
2043 		else
2044 			type = MLD2_MODE_IS_INCLUDE;
2045 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2046 	}
2047 	if (skb)
2048 		mld_sendpack(skb);
2049 }
2050 
2051 /* remove zero-count source records from a source filter list */
2052 static void mld_clear_zeros(struct ip6_sf_list __rcu **ppsf, struct inet6_dev *idev)
2053 {
2054 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
2055 
2056 	psf_prev = NULL;
2057 	for (psf = mc_dereference(*ppsf, idev);
2058 	     psf;
2059 	     psf = psf_next) {
2060 		psf_next = mc_dereference(psf->sf_next, idev);
2061 		if (psf->sf_crcount == 0) {
2062 			if (psf_prev)
2063 				rcu_assign_pointer(psf_prev->sf_next,
2064 						   mc_dereference(psf->sf_next, idev));
2065 			else
2066 				rcu_assign_pointer(*ppsf,
2067 						   mc_dereference(psf->sf_next, idev));
2068 			kfree_rcu(psf, rcu);
2069 		} else {
2070 			psf_prev = psf;
2071 		}
2072 	}
2073 }
2074 
2075 static void mld_send_cr(struct inet6_dev *idev)
2076 {
2077 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
2078 	struct sk_buff *skb = NULL;
2079 	int type, dtype;
2080 
2081 	/* deleted MCA's */
2082 	pmc_prev = NULL;
2083 	for (pmc = mc_dereference(idev->mc_tomb, idev);
2084 	     pmc;
2085 	     pmc = pmc_next) {
2086 		pmc_next = mc_dereference(pmc->next, idev);
2087 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
2088 			type = MLD2_BLOCK_OLD_SOURCES;
2089 			dtype = MLD2_BLOCK_OLD_SOURCES;
2090 			skb = add_grec(skb, pmc, type, 1, 0, 0);
2091 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
2092 		}
2093 		if (pmc->mca_crcount) {
2094 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
2095 				type = MLD2_CHANGE_TO_INCLUDE;
2096 				skb = add_grec(skb, pmc, type, 1, 0, 0);
2097 			}
2098 			pmc->mca_crcount--;
2099 			if (pmc->mca_crcount == 0) {
2100 				mld_clear_zeros(&pmc->mca_tomb, idev);
2101 				mld_clear_zeros(&pmc->mca_sources, idev);
2102 			}
2103 		}
2104 		if (pmc->mca_crcount == 0 &&
2105 		    !rcu_access_pointer(pmc->mca_tomb) &&
2106 		    !rcu_access_pointer(pmc->mca_sources)) {
2107 			if (pmc_prev)
2108 				rcu_assign_pointer(pmc_prev->next, pmc_next);
2109 			else
2110 				rcu_assign_pointer(idev->mc_tomb, pmc_next);
2111 			in6_dev_put(pmc->idev);
2112 			kfree_rcu(pmc, rcu);
2113 		} else
2114 			pmc_prev = pmc;
2115 	}
2116 
2117 	/* change recs */
2118 	for_each_mc_mclock(idev, pmc) {
2119 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2120 			type = MLD2_BLOCK_OLD_SOURCES;
2121 			dtype = MLD2_ALLOW_NEW_SOURCES;
2122 		} else {
2123 			type = MLD2_ALLOW_NEW_SOURCES;
2124 			dtype = MLD2_BLOCK_OLD_SOURCES;
2125 		}
2126 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2127 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
2128 
2129 		/* filter mode changes */
2130 		if (pmc->mca_crcount) {
2131 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
2132 				type = MLD2_CHANGE_TO_EXCLUDE;
2133 			else
2134 				type = MLD2_CHANGE_TO_INCLUDE;
2135 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2136 			pmc->mca_crcount--;
2137 		}
2138 	}
2139 	if (!skb)
2140 		return;
2141 	(void) mld_sendpack(skb);
2142 }
2143 
2144 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
2145 {
2146 	const struct in6_addr *snd_addr, *saddr;
2147 	int err, len, payload_len, full_len;
2148 	struct in6_addr addr_buf;
2149 	struct inet6_dev *idev;
2150 	struct sk_buff *skb;
2151 	struct mld_msg *hdr;
2152 	int hlen = LL_RESERVED_SPACE(dev);
2153 	int tlen = dev->needed_tailroom;
2154 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
2155 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
2156 		     IPV6_TLV_PADN, 0 };
2157 	struct dst_entry *dst;
2158 	struct flowi6 fl6;
2159 	struct net *net;
2160 	struct sock *sk;
2161 
2162 	if (type == ICMPV6_MGM_REDUCTION)
2163 		snd_addr = &in6addr_linklocal_allrouters;
2164 	else
2165 		snd_addr = addr;
2166 
2167 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2168 	payload_len = len + sizeof(ra);
2169 	full_len = sizeof(struct ipv6hdr) + payload_len;
2170 
2171 	skb = alloc_skb(hlen + tlen + full_len, GFP_KERNEL);
2172 
2173 	rcu_read_lock();
2174 
2175 	net = dev_net_rcu(dev);
2176 	idev = __in6_dev_get(dev);
2177 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
2178 	if (!skb) {
2179 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2180 		rcu_read_unlock();
2181 		return;
2182 	}
2183 	sk = net->ipv6.igmp_sk;
2184 	skb_set_owner_w(skb, sk);
2185 
2186 	skb->priority = TC_PRIO_CONTROL;
2187 	skb_reserve(skb, hlen);
2188 
2189 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2190 		/* <draft-ietf-magma-mld-source-05.txt>:
2191 		 * use unspecified address as the source address
2192 		 * when a valid link-local address is not available.
2193 		 */
2194 		saddr = &in6addr_any;
2195 	} else
2196 		saddr = &addr_buf;
2197 
2198 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2199 
2200 	skb_put_data(skb, ra, sizeof(ra));
2201 
2202 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2203 	hdr->mld_type = type;
2204 	hdr->mld_mca = *addr;
2205 
2206 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2207 					 IPPROTO_ICMPV6,
2208 					 csum_partial(hdr, len, 0));
2209 
2210 	icmpv6_flow_init(sk, &fl6, type,
2211 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2212 			 skb->dev->ifindex);
2213 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2214 	if (IS_ERR(dst)) {
2215 		err = PTR_ERR(dst);
2216 		goto err_out;
2217 	}
2218 
2219 	skb_dst_set(skb, dst);
2220 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2221 		      net, sk, skb, NULL, skb->dev,
2222 		      dst_output);
2223 out:
2224 	if (!err) {
2225 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2226 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2227 	} else
2228 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2229 
2230 	rcu_read_unlock();
2231 	return;
2232 
2233 err_out:
2234 	kfree_skb(skb);
2235 	goto out;
2236 }
2237 
2238 static void mld_send_initial_cr(struct inet6_dev *idev)
2239 {
2240 	struct ifmcaddr6 *pmc;
2241 	struct sk_buff *skb;
2242 	int type;
2243 
2244 	mc_assert_locked(idev);
2245 
2246 	if (mld_in_v1_mode(idev))
2247 		return;
2248 
2249 	skb = NULL;
2250 	for_each_mc_mclock(idev, pmc) {
2251 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2252 			type = MLD2_CHANGE_TO_EXCLUDE;
2253 		else
2254 			type = MLD2_ALLOW_NEW_SOURCES;
2255 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2256 	}
2257 	if (skb)
2258 		mld_sendpack(skb);
2259 }
2260 
2261 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2262 {
2263 	mutex_lock(&idev->mc_lock);
2264 	idev->mc_dad_count = idev->mc_qrv;
2265 	if (idev->mc_dad_count) {
2266 		mld_send_initial_cr(idev);
2267 		idev->mc_dad_count--;
2268 		if (idev->mc_dad_count)
2269 			mld_dad_start_work(idev,
2270 					   unsolicited_report_interval(idev));
2271 	}
2272 	mutex_unlock(&idev->mc_lock);
2273 }
2274 
2275 static void mld_dad_work(struct work_struct *work)
2276 {
2277 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2278 					      struct inet6_dev,
2279 					      mc_dad_work);
2280 	mutex_lock(&idev->mc_lock);
2281 	mld_send_initial_cr(idev);
2282 	if (idev->mc_dad_count) {
2283 		idev->mc_dad_count--;
2284 		if (idev->mc_dad_count)
2285 			mld_dad_start_work(idev,
2286 					   unsolicited_report_interval(idev));
2287 	}
2288 	mutex_unlock(&idev->mc_lock);
2289 	in6_dev_put(idev);
2290 }
2291 
2292 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2293 			   const struct in6_addr *psfsrc)
2294 {
2295 	struct ip6_sf_list *psf, *psf_prev;
2296 	int rv = 0;
2297 
2298 	mc_assert_locked(pmc->idev);
2299 
2300 	psf_prev = NULL;
2301 	for_each_psf_mclock(pmc, psf) {
2302 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2303 			break;
2304 		psf_prev = psf;
2305 	}
2306 	if (!psf || psf->sf_count[sfmode] == 0) {
2307 		/* source filter not found, or count wrong =>  bug */
2308 		return -ESRCH;
2309 	}
2310 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] - 1);
2311 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2312 		struct inet6_dev *idev = pmc->idev;
2313 
2314 		/* no more filters for this source */
2315 		if (psf_prev)
2316 			rcu_assign_pointer(psf_prev->sf_next,
2317 					   mc_dereference(psf->sf_next, idev));
2318 		else
2319 			rcu_assign_pointer(pmc->mca_sources,
2320 					   mc_dereference(psf->sf_next, idev));
2321 
2322 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2323 		    !mld_in_v1_mode(idev)) {
2324 			psf->sf_crcount = idev->mc_qrv;
2325 			rcu_assign_pointer(psf->sf_next,
2326 					   mc_dereference(pmc->mca_tomb, idev));
2327 			rcu_assign_pointer(pmc->mca_tomb, psf);
2328 			rv = 1;
2329 		} else {
2330 			kfree_rcu(psf, rcu);
2331 		}
2332 	}
2333 	return rv;
2334 }
2335 
2336 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2337 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2338 			  int delta)
2339 {
2340 	struct ifmcaddr6 *pmc;
2341 	int	changerec = 0;
2342 	int	i, err;
2343 
2344 	if (!idev)
2345 		return -ENODEV;
2346 
2347 	mc_assert_locked(idev);
2348 
2349 	for_each_mc_mclock(idev, pmc) {
2350 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2351 			break;
2352 	}
2353 	if (!pmc)
2354 		return -ESRCH;
2355 
2356 	sf_markstate(pmc);
2357 	if (!delta) {
2358 		if (!pmc->mca_sfcount[sfmode])
2359 			return -EINVAL;
2360 
2361 		pmc->mca_sfcount[sfmode]--;
2362 	}
2363 	err = 0;
2364 	for (i = 0; i < sfcount; i++) {
2365 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2366 
2367 		changerec |= rv > 0;
2368 		if (!err && rv < 0)
2369 			err = rv;
2370 	}
2371 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2372 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2373 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2374 		struct ip6_sf_list *psf;
2375 
2376 		/* filter mode change */
2377 		pmc->mca_sfmode = MCAST_INCLUDE;
2378 		pmc->mca_crcount = idev->mc_qrv;
2379 		idev->mc_ifc_count = pmc->mca_crcount;
2380 		for_each_psf_mclock(pmc, psf)
2381 			psf->sf_crcount = 0;
2382 		mld_ifc_event(pmc->idev);
2383 	} else if (sf_setstate(pmc) || changerec) {
2384 		mld_ifc_event(pmc->idev);
2385 	}
2386 
2387 	return err;
2388 }
2389 
2390 /* Add multicast single-source filter to the interface list */
2391 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2392 			   const struct in6_addr *psfsrc)
2393 {
2394 	struct ip6_sf_list *psf, *psf_prev;
2395 
2396 	mc_assert_locked(pmc->idev);
2397 
2398 	psf_prev = NULL;
2399 	for_each_psf_mclock(pmc, psf) {
2400 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2401 			break;
2402 		psf_prev = psf;
2403 	}
2404 	if (!psf) {
2405 		psf = kzalloc_obj(*psf);
2406 		if (!psf)
2407 			return -ENOBUFS;
2408 
2409 		psf->sf_addr = *psfsrc;
2410 		if (psf_prev) {
2411 			rcu_assign_pointer(psf_prev->sf_next, psf);
2412 		} else {
2413 			rcu_assign_pointer(pmc->mca_sources, psf);
2414 		}
2415 	}
2416 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] + 1);
2417 	return 0;
2418 }
2419 
2420 static void sf_markstate(struct ifmcaddr6 *pmc)
2421 {
2422 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2423 	struct ip6_sf_list *psf;
2424 
2425 	mc_assert_locked(pmc->idev);
2426 
2427 	for_each_psf_mclock(pmc, psf) {
2428 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2429 			psf->sf_oldin = mca_xcount ==
2430 				psf->sf_count[MCAST_EXCLUDE] &&
2431 				!psf->sf_count[MCAST_INCLUDE];
2432 		} else {
2433 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2434 		}
2435 	}
2436 }
2437 
2438 static int sf_setstate(struct ifmcaddr6 *pmc)
2439 {
2440 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2441 	struct ip6_sf_list *psf, *dpsf;
2442 	int qrv = pmc->idev->mc_qrv;
2443 	int new_in, rv;
2444 
2445 	mc_assert_locked(pmc->idev);
2446 
2447 	rv = 0;
2448 	for_each_psf_mclock(pmc, psf) {
2449 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2450 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2451 				!psf->sf_count[MCAST_INCLUDE];
2452 		} else
2453 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2454 		if (new_in) {
2455 			if (!psf->sf_oldin) {
2456 				struct ip6_sf_list *prev = NULL;
2457 
2458 				for_each_psf_tomb(pmc, dpsf) {
2459 					if (ipv6_addr_equal(&dpsf->sf_addr,
2460 					    &psf->sf_addr))
2461 						break;
2462 					prev = dpsf;
2463 				}
2464 				if (dpsf) {
2465 					if (prev)
2466 						rcu_assign_pointer(prev->sf_next,
2467 								   mc_dereference(dpsf->sf_next,
2468 										  pmc->idev));
2469 					else
2470 						rcu_assign_pointer(pmc->mca_tomb,
2471 								   mc_dereference(dpsf->sf_next,
2472 										  pmc->idev));
2473 					kfree_rcu(dpsf, rcu);
2474 				}
2475 				psf->sf_crcount = qrv;
2476 				rv++;
2477 			}
2478 		} else if (psf->sf_oldin) {
2479 			psf->sf_crcount = 0;
2480 			/*
2481 			 * add or update "delete" records if an active filter
2482 			 * is now inactive
2483 			 */
2484 
2485 			for_each_psf_tomb(pmc, dpsf)
2486 				if (ipv6_addr_equal(&dpsf->sf_addr,
2487 				    &psf->sf_addr))
2488 					break;
2489 			if (!dpsf) {
2490 				dpsf = kmalloc_obj(*dpsf);
2491 				if (!dpsf)
2492 					continue;
2493 				*dpsf = *psf;
2494 				rcu_assign_pointer(dpsf->sf_next,
2495 						   mc_dereference(pmc->mca_tomb, pmc->idev));
2496 				rcu_assign_pointer(pmc->mca_tomb, dpsf);
2497 			}
2498 			dpsf->sf_crcount = qrv;
2499 			rv++;
2500 		}
2501 	}
2502 	return rv;
2503 }
2504 
2505 /* Add multicast source filter list to the interface list */
2506 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2507 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2508 			  int delta)
2509 {
2510 	struct ifmcaddr6 *pmc;
2511 	int	isexclude;
2512 	int	i, err;
2513 
2514 	if (!idev)
2515 		return -ENODEV;
2516 
2517 	mc_assert_locked(idev);
2518 
2519 	for_each_mc_mclock(idev, pmc) {
2520 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2521 			break;
2522 	}
2523 	if (!pmc)
2524 		return -ESRCH;
2525 
2526 	sf_markstate(pmc);
2527 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2528 	if (!delta)
2529 		WRITE_ONCE(pmc->mca_sfcount[sfmode],
2530 			   pmc->mca_sfcount[sfmode] + 1);
2531 	err = 0;
2532 	for (i = 0; i < sfcount; i++) {
2533 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2534 		if (err)
2535 			break;
2536 	}
2537 	if (err) {
2538 		int j;
2539 
2540 		if (!delta)
2541 			WRITE_ONCE(pmc->mca_sfcount[sfmode],
2542 				   pmc->mca_sfcount[sfmode] - 1);
2543 		for (j = 0; j < i; j++)
2544 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2545 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2546 		struct ip6_sf_list *psf;
2547 
2548 		/* filter mode change */
2549 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2550 			pmc->mca_sfmode = MCAST_EXCLUDE;
2551 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2552 			pmc->mca_sfmode = MCAST_INCLUDE;
2553 		/* else no filters; keep old mode for reports */
2554 
2555 		pmc->mca_crcount = idev->mc_qrv;
2556 		idev->mc_ifc_count = pmc->mca_crcount;
2557 		for_each_psf_mclock(pmc, psf)
2558 			psf->sf_crcount = 0;
2559 		mld_ifc_event(idev);
2560 	} else if (sf_setstate(pmc)) {
2561 		mld_ifc_event(idev);
2562 	}
2563 	return err;
2564 }
2565 
2566 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2567 {
2568 	struct ip6_sf_list *psf, *nextpsf;
2569 
2570 	mc_assert_locked(pmc->idev);
2571 
2572 	for (psf = mc_dereference(pmc->mca_tomb, pmc->idev);
2573 	     psf;
2574 	     psf = nextpsf) {
2575 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2576 		kfree_rcu(psf, rcu);
2577 	}
2578 	RCU_INIT_POINTER(pmc->mca_tomb, NULL);
2579 	for (psf = mc_dereference(pmc->mca_sources, pmc->idev);
2580 	     psf;
2581 	     psf = nextpsf) {
2582 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2583 		kfree_rcu(psf, rcu);
2584 	}
2585 	RCU_INIT_POINTER(pmc->mca_sources, NULL);
2586 	pmc->mca_sfmode = MCAST_EXCLUDE;
2587 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2588 	/* Paired with the READ_ONCE() from ipv6_chk_mcast_addr() */
2589 	WRITE_ONCE(pmc->mca_sfcount[MCAST_EXCLUDE], 1);
2590 }
2591 
2592 static void igmp6_join_group(struct ifmcaddr6 *ma)
2593 {
2594 	unsigned long delay;
2595 
2596 	mc_assert_locked(ma->idev);
2597 
2598 	if (ma->mca_flags & MAF_NOREPORT)
2599 		return;
2600 
2601 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2602 
2603 	delay = get_random_u32_below(unsolicited_report_interval(ma->idev));
2604 
2605 	if (cancel_delayed_work(&ma->mca_work)) {
2606 		refcount_dec(&ma->mca_refcnt);
2607 		delay = ma->mca_work.timer.expires - jiffies;
2608 	}
2609 
2610 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
2611 		refcount_inc(&ma->mca_refcnt);
2612 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2613 }
2614 
2615 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2616 			    struct inet6_dev *idev)
2617 {
2618 	struct ip6_sf_socklist *psl;
2619 	int err;
2620 
2621 	psl = sock_dereference(iml->sflist, sk);
2622 
2623 	if (idev)
2624 		mutex_lock(&idev->mc_lock);
2625 
2626 	if (!psl) {
2627 		/* any-source empty exclude case */
2628 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2629 	} else {
2630 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2631 				     psl->sl_count, psl->sl_addr, 0);
2632 		RCU_INIT_POINTER(iml->sflist, NULL);
2633 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2634 			   &sk->sk_omem_alloc);
2635 		kfree_rcu(psl, rcu);
2636 	}
2637 
2638 	if (idev)
2639 		mutex_unlock(&idev->mc_lock);
2640 
2641 	return err;
2642 }
2643 
2644 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2645 {
2646 	mc_assert_locked(ma->idev);
2647 
2648 	if (mld_in_v1_mode(ma->idev)) {
2649 		if (ma->mca_flags & MAF_LAST_REPORTER) {
2650 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2651 				ICMPV6_MGM_REDUCTION);
2652 		}
2653 	} else {
2654 		mld_add_delrec(ma->idev, ma);
2655 		mld_ifc_event(ma->idev);
2656 	}
2657 }
2658 
2659 static void mld_gq_work(struct work_struct *work)
2660 {
2661 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2662 					      struct inet6_dev,
2663 					      mc_gq_work);
2664 
2665 	mutex_lock(&idev->mc_lock);
2666 	mld_send_report(idev, NULL);
2667 	idev->mc_gq_running = 0;
2668 	mutex_unlock(&idev->mc_lock);
2669 
2670 	in6_dev_put(idev);
2671 }
2672 
2673 static void mld_ifc_work(struct work_struct *work)
2674 {
2675 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2676 					      struct inet6_dev,
2677 					      mc_ifc_work);
2678 
2679 	mutex_lock(&idev->mc_lock);
2680 	mld_send_cr(idev);
2681 
2682 	if (idev->mc_ifc_count) {
2683 		idev->mc_ifc_count--;
2684 		if (idev->mc_ifc_count)
2685 			mld_ifc_start_work(idev,
2686 					   unsolicited_report_interval(idev));
2687 	}
2688 	mutex_unlock(&idev->mc_lock);
2689 	in6_dev_put(idev);
2690 }
2691 
2692 static void mld_ifc_event(struct inet6_dev *idev)
2693 {
2694 	mc_assert_locked(idev);
2695 
2696 	if (mld_in_v1_mode(idev))
2697 		return;
2698 
2699 	idev->mc_ifc_count = idev->mc_qrv;
2700 	mld_ifc_start_work(idev, 1);
2701 }
2702 
2703 static void mld_mca_work(struct work_struct *work)
2704 {
2705 	struct ifmcaddr6 *ma = container_of(to_delayed_work(work),
2706 					    struct ifmcaddr6, mca_work);
2707 
2708 	mutex_lock(&ma->idev->mc_lock);
2709 	if (mld_in_v1_mode(ma->idev))
2710 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2711 	else
2712 		mld_send_report(ma->idev, ma);
2713 	ma->mca_flags |=  MAF_LAST_REPORTER;
2714 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2715 	mutex_unlock(&ma->idev->mc_lock);
2716 
2717 	ma_put(ma);
2718 }
2719 
2720 /* Device changing type */
2721 
2722 void ipv6_mc_unmap(struct inet6_dev *idev)
2723 {
2724 	struct ifmcaddr6 *i;
2725 
2726 	/* Install multicast list, except for all-nodes (already installed) */
2727 
2728 	mutex_lock(&idev->mc_lock);
2729 	for_each_mc_mclock(idev, i)
2730 		igmp6_group_dropped(i);
2731 	mutex_unlock(&idev->mc_lock);
2732 }
2733 
2734 void ipv6_mc_remap(struct inet6_dev *idev)
2735 {
2736 	ipv6_mc_up(idev);
2737 }
2738 
2739 /* Device going down */
2740 void ipv6_mc_down(struct inet6_dev *idev)
2741 {
2742 	struct ifmcaddr6 *i;
2743 
2744 	mutex_lock(&idev->mc_lock);
2745 	/* Withdraw multicast list */
2746 	for_each_mc_mclock(idev, i)
2747 		igmp6_group_dropped(i);
2748 	mutex_unlock(&idev->mc_lock);
2749 
2750 	/* Should stop work after group drop. or we will
2751 	 * start work again in mld_ifc_event()
2752 	 */
2753 	mld_query_stop_work(idev);
2754 	mld_report_stop_work(idev);
2755 
2756 	mutex_lock(&idev->mc_lock);
2757 	mld_ifc_stop_work(idev);
2758 	mld_gq_stop_work(idev);
2759 	mutex_unlock(&idev->mc_lock);
2760 
2761 	mld_dad_stop_work(idev);
2762 }
2763 
2764 static void ipv6_mc_reset(struct inet6_dev *idev)
2765 {
2766 	idev->mc_qrv = sysctl_mld_qrv;
2767 	idev->mc_qi = MLD_QI_DEFAULT;
2768 	idev->mc_qri = MLD_QRI_DEFAULT;
2769 	idev->mc_v1_seen = 0;
2770 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2771 }
2772 
2773 /* Device going up */
2774 
2775 void ipv6_mc_up(struct inet6_dev *idev)
2776 {
2777 	struct ifmcaddr6 *i;
2778 
2779 	/* Install multicast list, except for all-nodes (already installed) */
2780 
2781 	ipv6_mc_reset(idev);
2782 	mutex_lock(&idev->mc_lock);
2783 	for_each_mc_mclock(idev, i) {
2784 		mld_del_delrec(idev, i);
2785 		igmp6_group_added(i);
2786 	}
2787 	mutex_unlock(&idev->mc_lock);
2788 }
2789 
2790 /* IPv6 device initialization. */
2791 
2792 void ipv6_mc_init_dev(struct inet6_dev *idev)
2793 {
2794 	idev->mc_gq_running = 0;
2795 	INIT_DELAYED_WORK(&idev->mc_gq_work, mld_gq_work);
2796 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
2797 	idev->mc_ifc_count = 0;
2798 	INIT_DELAYED_WORK(&idev->mc_ifc_work, mld_ifc_work);
2799 	INIT_DELAYED_WORK(&idev->mc_dad_work, mld_dad_work);
2800 	INIT_DELAYED_WORK(&idev->mc_query_work, mld_query_work);
2801 	INIT_DELAYED_WORK(&idev->mc_report_work, mld_report_work);
2802 	skb_queue_head_init(&idev->mc_query_queue);
2803 	skb_queue_head_init(&idev->mc_report_queue);
2804 	spin_lock_init(&idev->mc_query_lock);
2805 	spin_lock_init(&idev->mc_report_lock);
2806 	mutex_init(&idev->mc_lock);
2807 	ipv6_mc_reset(idev);
2808 }
2809 
2810 /*
2811  *	Device is about to be destroyed: clean up.
2812  */
2813 
2814 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2815 {
2816 	struct ifmcaddr6 *i;
2817 
2818 	/* Deactivate works */
2819 	ipv6_mc_down(idev);
2820 	mutex_lock(&idev->mc_lock);
2821 	mld_clear_delrec(idev);
2822 	mutex_unlock(&idev->mc_lock);
2823 	mld_clear_query(idev);
2824 	mld_clear_report(idev);
2825 
2826 	/* Delete all-nodes address. */
2827 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2828 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2829 	 * fail.
2830 	 */
2831 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2832 
2833 	if (idev->cnf.forwarding)
2834 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2835 
2836 	mutex_lock(&idev->mc_lock);
2837 	while ((i = mc_dereference(idev->mc_list, idev))) {
2838 		rcu_assign_pointer(idev->mc_list, mc_dereference(i->next, idev));
2839 
2840 		ip6_mc_clear_src(i);
2841 		ma_put(i);
2842 	}
2843 	mutex_unlock(&idev->mc_lock);
2844 }
2845 
2846 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2847 {
2848 	struct ifmcaddr6 *pmc;
2849 
2850 	mutex_lock(&idev->mc_lock);
2851 	if (mld_in_v1_mode(idev)) {
2852 		for_each_mc_mclock(idev, pmc)
2853 			igmp6_join_group(pmc);
2854 	} else {
2855 		mld_send_report(idev, NULL);
2856 	}
2857 	mutex_unlock(&idev->mc_lock);
2858 }
2859 
2860 static int ipv6_mc_netdev_event(struct notifier_block *this,
2861 				unsigned long event,
2862 				void *ptr)
2863 {
2864 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2865 	struct inet6_dev *idev = __in6_dev_get(dev);
2866 
2867 	switch (event) {
2868 	case NETDEV_RESEND_IGMP:
2869 		if (idev)
2870 			ipv6_mc_rejoin_groups(idev);
2871 		break;
2872 	default:
2873 		break;
2874 	}
2875 
2876 	return NOTIFY_DONE;
2877 }
2878 
2879 static struct notifier_block igmp6_netdev_notifier = {
2880 	.notifier_call = ipv6_mc_netdev_event,
2881 };
2882 
2883 #ifdef CONFIG_PROC_FS
2884 struct igmp6_mc_iter_state {
2885 	struct seq_net_private p;
2886 	struct net_device *dev;
2887 	struct inet6_dev *idev;
2888 };
2889 
2890 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2891 
2892 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2893 {
2894 	struct ifmcaddr6 *im = NULL;
2895 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2896 	struct net *net = seq_file_net(seq);
2897 
2898 	state->idev = NULL;
2899 	for_each_netdev_rcu(net, state->dev) {
2900 		struct inet6_dev *idev;
2901 		idev = __in6_dev_get(state->dev);
2902 		if (!idev)
2903 			continue;
2904 
2905 		im = rcu_dereference(idev->mc_list);
2906 		if (im) {
2907 			state->idev = idev;
2908 			break;
2909 		}
2910 	}
2911 	return im;
2912 }
2913 
2914 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2915 {
2916 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2917 
2918 	im = rcu_dereference(im->next);
2919 	while (!im) {
2920 		state->dev = next_net_device_rcu(state->dev);
2921 		if (!state->dev) {
2922 			state->idev = NULL;
2923 			break;
2924 		}
2925 		state->idev = __in6_dev_get(state->dev);
2926 		if (!state->idev)
2927 			continue;
2928 		im = rcu_dereference(state->idev->mc_list);
2929 	}
2930 	return im;
2931 }
2932 
2933 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2934 {
2935 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2936 	if (im)
2937 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2938 			--pos;
2939 	return pos ? NULL : im;
2940 }
2941 
2942 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2943 	__acquires(RCU)
2944 {
2945 	rcu_read_lock();
2946 	return igmp6_mc_get_idx(seq, *pos);
2947 }
2948 
2949 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2950 {
2951 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2952 
2953 	++*pos;
2954 	return im;
2955 }
2956 
2957 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2958 	__releases(RCU)
2959 {
2960 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2961 
2962 	if (likely(state->idev))
2963 		state->idev = NULL;
2964 	state->dev = NULL;
2965 	rcu_read_unlock();
2966 }
2967 
2968 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2969 {
2970 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2971 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2972 
2973 	seq_printf(seq,
2974 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2975 		   state->dev->ifindex, state->dev->name,
2976 		   &im->mca_addr,
2977 		   im->mca_users, im->mca_flags,
2978 		   (im->mca_flags & MAF_TIMER_RUNNING) ?
2979 		   jiffies_to_clock_t(im->mca_work.timer.expires - jiffies) : 0);
2980 	return 0;
2981 }
2982 
2983 static const struct seq_operations igmp6_mc_seq_ops = {
2984 	.start	=	igmp6_mc_seq_start,
2985 	.next	=	igmp6_mc_seq_next,
2986 	.stop	=	igmp6_mc_seq_stop,
2987 	.show	=	igmp6_mc_seq_show,
2988 };
2989 
2990 struct igmp6_mcf_iter_state {
2991 	struct seq_net_private p;
2992 	struct net_device *dev;
2993 	struct inet6_dev *idev;
2994 	struct ifmcaddr6 *im;
2995 };
2996 
2997 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2998 
2999 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
3000 {
3001 	struct ip6_sf_list *psf = NULL;
3002 	struct ifmcaddr6 *im = NULL;
3003 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3004 	struct net *net = seq_file_net(seq);
3005 
3006 	state->idev = NULL;
3007 	state->im = NULL;
3008 	for_each_netdev_rcu(net, state->dev) {
3009 		struct inet6_dev *idev;
3010 		idev = __in6_dev_get(state->dev);
3011 		if (unlikely(idev == NULL))
3012 			continue;
3013 
3014 		im = rcu_dereference(idev->mc_list);
3015 		if (likely(im)) {
3016 			psf = rcu_dereference(im->mca_sources);
3017 			if (likely(psf)) {
3018 				state->im = im;
3019 				state->idev = idev;
3020 				break;
3021 			}
3022 		}
3023 	}
3024 	return psf;
3025 }
3026 
3027 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
3028 {
3029 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3030 
3031 	psf = rcu_dereference(psf->sf_next);
3032 	while (!psf) {
3033 		state->im = rcu_dereference(state->im->next);
3034 		while (!state->im) {
3035 			state->dev = next_net_device_rcu(state->dev);
3036 			if (!state->dev) {
3037 				state->idev = NULL;
3038 				goto out;
3039 			}
3040 			state->idev = __in6_dev_get(state->dev);
3041 			if (!state->idev)
3042 				continue;
3043 			state->im = rcu_dereference(state->idev->mc_list);
3044 		}
3045 		psf = rcu_dereference(state->im->mca_sources);
3046 	}
3047 out:
3048 	return psf;
3049 }
3050 
3051 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
3052 {
3053 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
3054 	if (psf)
3055 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
3056 			--pos;
3057 	return pos ? NULL : psf;
3058 }
3059 
3060 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
3061 	__acquires(RCU)
3062 {
3063 	rcu_read_lock();
3064 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
3065 }
3066 
3067 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3068 {
3069 	struct ip6_sf_list *psf;
3070 	if (v == SEQ_START_TOKEN)
3071 		psf = igmp6_mcf_get_first(seq);
3072 	else
3073 		psf = igmp6_mcf_get_next(seq, v);
3074 	++*pos;
3075 	return psf;
3076 }
3077 
3078 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
3079 	__releases(RCU)
3080 {
3081 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3082 
3083 	if (likely(state->im))
3084 		state->im = NULL;
3085 	if (likely(state->idev))
3086 		state->idev = NULL;
3087 
3088 	state->dev = NULL;
3089 	rcu_read_unlock();
3090 }
3091 
3092 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
3093 {
3094 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
3095 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3096 
3097 	if (v == SEQ_START_TOKEN) {
3098 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
3099 	} else {
3100 		seq_printf(seq,
3101 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
3102 			   state->dev->ifindex, state->dev->name,
3103 			   &state->im->mca_addr,
3104 			   &psf->sf_addr,
3105 			   READ_ONCE(psf->sf_count[MCAST_INCLUDE]),
3106 			   READ_ONCE(psf->sf_count[MCAST_EXCLUDE]));
3107 	}
3108 	return 0;
3109 }
3110 
3111 static const struct seq_operations igmp6_mcf_seq_ops = {
3112 	.start	=	igmp6_mcf_seq_start,
3113 	.next	=	igmp6_mcf_seq_next,
3114 	.stop	=	igmp6_mcf_seq_stop,
3115 	.show	=	igmp6_mcf_seq_show,
3116 };
3117 
3118 static int __net_init igmp6_proc_init(struct net *net)
3119 {
3120 	int err;
3121 
3122 	err = -ENOMEM;
3123 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
3124 			sizeof(struct igmp6_mc_iter_state)))
3125 		goto out;
3126 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
3127 			&igmp6_mcf_seq_ops,
3128 			sizeof(struct igmp6_mcf_iter_state)))
3129 		goto out_proc_net_igmp6;
3130 
3131 	err = 0;
3132 out:
3133 	return err;
3134 
3135 out_proc_net_igmp6:
3136 	remove_proc_entry("igmp6", net->proc_net);
3137 	goto out;
3138 }
3139 
3140 static void __net_exit igmp6_proc_exit(struct net *net)
3141 {
3142 	remove_proc_entry("mcfilter6", net->proc_net);
3143 	remove_proc_entry("igmp6", net->proc_net);
3144 }
3145 #else
3146 static inline int igmp6_proc_init(struct net *net)
3147 {
3148 	return 0;
3149 }
3150 static inline void igmp6_proc_exit(struct net *net)
3151 {
3152 }
3153 #endif
3154 
3155 static int __net_init igmp6_net_init(struct net *net)
3156 {
3157 	int err;
3158 
3159 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
3160 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3161 	if (err < 0) {
3162 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
3163 		       err);
3164 		goto out;
3165 	}
3166 
3167 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
3168 	net->ipv6.igmp_sk->sk_allocation = GFP_KERNEL;
3169 
3170 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
3171 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3172 	if (err < 0) {
3173 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
3174 		       err);
3175 		goto out_sock_create;
3176 	}
3177 
3178 	err = igmp6_proc_init(net);
3179 	if (err)
3180 		goto out_sock_create_autojoin;
3181 
3182 	return 0;
3183 
3184 out_sock_create_autojoin:
3185 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3186 out_sock_create:
3187 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3188 out:
3189 	return err;
3190 }
3191 
3192 static void __net_exit igmp6_net_exit(struct net *net)
3193 {
3194 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3195 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3196 	igmp6_proc_exit(net);
3197 }
3198 
3199 static struct pernet_operations igmp6_net_ops = {
3200 	.init = igmp6_net_init,
3201 	.exit = igmp6_net_exit,
3202 };
3203 
3204 int __init igmp6_init(void)
3205 {
3206 	int err;
3207 
3208 	err = register_pernet_subsys(&igmp6_net_ops);
3209 	if (err)
3210 		return err;
3211 
3212 	mld_wq = create_workqueue("mld");
3213 	if (!mld_wq) {
3214 		unregister_pernet_subsys(&igmp6_net_ops);
3215 		return -ENOMEM;
3216 	}
3217 
3218 	return err;
3219 }
3220 
3221 int __init igmp6_late_init(void)
3222 {
3223 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3224 }
3225 
3226 void igmp6_cleanup(void)
3227 {
3228 	unregister_pernet_subsys(&igmp6_net_ops);
3229 	destroy_workqueue(mld_wq);
3230 }
3231 
3232 void igmp6_late_cleanup(void)
3233 {
3234 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3235 }
3236