xref: /linux/net/ipv6/mcast.c (revision 26ba30221c03364d6ed9910be8da4c1fd871b07b)
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 		WRITE_ONCE(mc->mca_flags, 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 		WRITE_ONCE(mc->mca_flags, 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 	WRITE_ONCE(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 		WRITE_ONCE(mc->mca_flags, 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(u32)) +
912 			nla_total_size(sizeof(struct ifa_cacheinfo)),
913 			GFP_KERNEL);
914 	if (!skb)
915 		goto error;
916 
917 	err = inet6_fill_ifmcaddr(skb, ifmca, &fillargs);
918 	if (err < 0) {
919 		WARN_ON_ONCE(err == -EMSGSIZE);
920 		nlmsg_free(skb);
921 		goto error;
922 	}
923 
924 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MCADDR, NULL, GFP_KERNEL);
925 	return;
926 error:
927 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MCADDR, err);
928 }
929 
930 /*
931  *	device multicast group inc (add if not found)
932  */
933 static int __ipv6_dev_mc_inc(struct net_device *dev,
934 			     const struct in6_addr *addr, unsigned int mode)
935 {
936 	struct inet6_dev *idev;
937 	struct ifmcaddr6 *mc;
938 
939 	/* we need to take a reference on idev */
940 	idev = in6_dev_get(dev);
941 	if (!idev)
942 		return -EINVAL;
943 
944 	mutex_lock(&idev->mc_lock);
945 
946 	if (READ_ONCE(idev->dead)) {
947 		mutex_unlock(&idev->mc_lock);
948 		in6_dev_put(idev);
949 		return -ENODEV;
950 	}
951 
952 	for_each_mc_mclock(idev, mc) {
953 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
954 			WRITE_ONCE(mc->mca_users, mc->mca_users + 1);
955 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
956 			mutex_unlock(&idev->mc_lock);
957 			in6_dev_put(idev);
958 			return 0;
959 		}
960 	}
961 
962 	mc = mca_alloc(idev, addr, mode);
963 	if (!mc) {
964 		mutex_unlock(&idev->mc_lock);
965 		in6_dev_put(idev);
966 		return -ENOMEM;
967 	}
968 
969 	rcu_assign_pointer(mc->next, idev->mc_list);
970 	rcu_assign_pointer(idev->mc_list, mc);
971 
972 	mld_del_delrec(idev, mc);
973 	igmp6_group_added(mc);
974 	inet6_ifmcaddr_notify(dev, mc, RTM_NEWMULTICAST);
975 	mutex_unlock(&idev->mc_lock);
976 
977 	return 0;
978 }
979 
980 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
981 {
982 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
983 }
984 EXPORT_SYMBOL(ipv6_dev_mc_inc);
985 
986 /*
987  * device multicast group del
988  */
989 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
990 {
991 	struct ifmcaddr6 *ma, __rcu **map;
992 
993 	mutex_lock(&idev->mc_lock);
994 
995 	for (map = &idev->mc_list;
996 	     (ma = mc_dereference(*map, idev));
997 	     map = &ma->next) {
998 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
999 			int new_users = ma->mca_users - 1;
1000 
1001 			WRITE_ONCE(ma->mca_users, new_users);
1002 			if (new_users == 0) {
1003 				*map = ma->next;
1004 
1005 				igmp6_group_dropped(ma);
1006 				inet6_ifmcaddr_notify(idev->dev, ma,
1007 						      RTM_DELMULTICAST);
1008 				ip6_mc_clear_src(ma);
1009 				mutex_unlock(&idev->mc_lock);
1010 
1011 				ma_put(ma);
1012 				return 0;
1013 			}
1014 			mutex_unlock(&idev->mc_lock);
1015 			return 0;
1016 		}
1017 	}
1018 
1019 	mutex_unlock(&idev->mc_lock);
1020 	return -ENOENT;
1021 }
1022 
1023 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
1024 {
1025 	struct inet6_dev *idev;
1026 	int err;
1027 
1028 	idev = in6_dev_get(dev);
1029 	if (!idev)
1030 		return -ENODEV;
1031 
1032 	err = __ipv6_dev_mc_dec(idev, addr);
1033 	in6_dev_put(idev);
1034 
1035 	return err;
1036 }
1037 EXPORT_SYMBOL(ipv6_dev_mc_dec);
1038 
1039 /*
1040  *	check if the interface/address pair is valid
1041  */
1042 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
1043 			 const struct in6_addr *src_addr)
1044 {
1045 	struct inet6_dev *idev;
1046 	struct ifmcaddr6 *mc;
1047 	bool rv = false;
1048 
1049 	rcu_read_lock();
1050 	idev = __in6_dev_get(dev);
1051 	if (!idev)
1052 		goto unlock;
1053 	for_each_mc_rcu(idev, mc) {
1054 		if (ipv6_addr_equal(&mc->mca_addr, group))
1055 			break;
1056 	}
1057 	if (!mc)
1058 		goto unlock;
1059 	if (src_addr && !ipv6_addr_any(src_addr)) {
1060 		struct ip6_sf_list *psf;
1061 
1062 		for_each_psf_rcu(mc, psf) {
1063 			if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1064 				break;
1065 		}
1066 		if (psf)
1067 			rv = READ_ONCE(psf->sf_count[MCAST_INCLUDE]) ||
1068 				READ_ONCE(psf->sf_count[MCAST_EXCLUDE]) !=
1069 				READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]);
1070 		else
1071 			rv = READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]) != 0;
1072 	} else {
1073 		rv = true; /* don't filter unspecified source */
1074 	}
1075 unlock:
1076 	rcu_read_unlock();
1077 	return rv;
1078 }
1079 
1080 static void mld_gq_start_work(struct inet6_dev *idev)
1081 {
1082 	unsigned long tv = get_random_u32_below(idev->mc_maxdelay);
1083 
1084 	mc_assert_locked(idev);
1085 
1086 	idev->mc_gq_running = 1;
1087 	if (in6_dev_hold_safe(idev)) {
1088 		if (mod_delayed_work(mld_wq, &idev->mc_gq_work, tv + 2))
1089 			in6_dev_put(idev);
1090 	}
1091 }
1092 
1093 static void mld_gq_stop_work(struct inet6_dev *idev)
1094 {
1095 	mc_assert_locked(idev);
1096 
1097 	idev->mc_gq_running = 0;
1098 	if (cancel_delayed_work(&idev->mc_gq_work))
1099 		__in6_dev_put(idev);
1100 }
1101 
1102 static void mld_ifc_start_work(struct inet6_dev *idev, unsigned long delay)
1103 {
1104 	unsigned long tv = get_random_u32_below(delay);
1105 
1106 	mc_assert_locked(idev);
1107 
1108 	if (in6_dev_hold_safe(idev)) {
1109 		if (mod_delayed_work(mld_wq, &idev->mc_ifc_work, tv + 2))
1110 			in6_dev_put(idev);
1111 	}
1112 }
1113 
1114 static void mld_ifc_stop_work(struct inet6_dev *idev)
1115 {
1116 	mc_assert_locked(idev);
1117 
1118 	idev->mc_ifc_count = 0;
1119 	if (cancel_delayed_work(&idev->mc_ifc_work))
1120 		__in6_dev_put(idev);
1121 }
1122 
1123 static void mld_dad_start_work(struct inet6_dev *idev, unsigned long delay)
1124 {
1125 	unsigned long tv = get_random_u32_below(delay);
1126 
1127 	mc_assert_locked(idev);
1128 
1129 	if (in6_dev_hold_safe(idev)) {
1130 		if (mod_delayed_work(mld_wq, &idev->mc_dad_work, tv + 2))
1131 			in6_dev_put(idev);
1132 	}
1133 }
1134 
1135 static void mld_dad_stop_work(struct inet6_dev *idev)
1136 {
1137 	if (cancel_delayed_work(&idev->mc_dad_work))
1138 		__in6_dev_put(idev);
1139 }
1140 
1141 static void mld_query_stop_work(struct inet6_dev *idev)
1142 {
1143 	spin_lock_bh(&idev->mc_query_lock);
1144 	if (cancel_delayed_work(&idev->mc_query_work))
1145 		__in6_dev_put(idev);
1146 	spin_unlock_bh(&idev->mc_query_lock);
1147 }
1148 
1149 static void mld_report_stop_work(struct inet6_dev *idev)
1150 {
1151 	if (cancel_delayed_work_sync(&idev->mc_report_work))
1152 		__in6_dev_put(idev);
1153 }
1154 
1155 /* IGMP handling (alias multicast ICMPv6 messages) */
1156 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1157 {
1158 	unsigned long delay = resptime;
1159 
1160 	mc_assert_locked(ma->idev);
1161 
1162 	/* Do not start work for these addresses */
1163 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1164 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1165 		return;
1166 
1167 	if (cancel_delayed_work(&ma->mca_work)) {
1168 		refcount_dec(&ma->mca_refcnt);
1169 		delay = ma->mca_work.timer.expires - jiffies;
1170 	}
1171 
1172 	if (delay >= resptime)
1173 		delay = get_random_u32_below(resptime);
1174 
1175 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
1176 		refcount_inc(&ma->mca_refcnt);
1177 	WRITE_ONCE(ma->mca_flags, ma->mca_flags | MAF_TIMER_RUNNING);
1178 }
1179 
1180 /* mark EXCLUDE-mode sources */
1181 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1182 			     const struct in6_addr *srcs)
1183 {
1184 	struct ip6_sf_list *psf;
1185 	int i, scount;
1186 
1187 	mc_assert_locked(pmc->idev);
1188 
1189 	scount = 0;
1190 	for_each_psf_mclock(pmc, psf) {
1191 		if (scount == nsrcs)
1192 			break;
1193 		for (i = 0; i < nsrcs; i++) {
1194 			/* skip inactive filters */
1195 			if (psf->sf_count[MCAST_INCLUDE] ||
1196 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1197 			    psf->sf_count[MCAST_EXCLUDE])
1198 				break;
1199 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1200 				scount++;
1201 				break;
1202 			}
1203 		}
1204 	}
1205 	WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
1206 	if (scount == nsrcs)	/* all sources excluded */
1207 		return false;
1208 	return true;
1209 }
1210 
1211 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1212 			    const struct in6_addr *srcs)
1213 {
1214 	struct ip6_sf_list *psf;
1215 	int i, scount;
1216 
1217 	mc_assert_locked(pmc->idev);
1218 
1219 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1220 		return mld_xmarksources(pmc, nsrcs, srcs);
1221 
1222 	/* mark INCLUDE-mode sources */
1223 
1224 	scount = 0;
1225 	for_each_psf_mclock(pmc, psf) {
1226 		if (scount == nsrcs)
1227 			break;
1228 		for (i = 0; i < nsrcs; i++) {
1229 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1230 				psf->sf_gsresp = 1;
1231 				scount++;
1232 				break;
1233 			}
1234 		}
1235 	}
1236 	if (!scount) {
1237 		WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
1238 		return false;
1239 	}
1240 	WRITE_ONCE(pmc->mca_flags, pmc->mca_flags | MAF_GSQUERY);
1241 	return true;
1242 }
1243 
1244 static int mld_force_mld_version(const struct inet6_dev *idev)
1245 {
1246 	const struct net *net = dev_net(idev->dev);
1247 	int all_force;
1248 
1249 	all_force = READ_ONCE(net->ipv6.devconf_all->force_mld_version);
1250 	/* Normally, both are 0 here. If enforcement to a particular is
1251 	 * being used, individual device enforcement will have a lower
1252 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1253 	 */
1254 	return all_force ?: READ_ONCE(idev->cnf.force_mld_version);
1255 }
1256 
1257 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1258 {
1259 	return mld_force_mld_version(idev) == 2;
1260 }
1261 
1262 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1263 {
1264 	return mld_force_mld_version(idev) == 1;
1265 }
1266 
1267 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1268 {
1269 	if (mld_in_v2_mode_only(idev))
1270 		return false;
1271 	if (mld_in_v1_mode_only(idev))
1272 		return true;
1273 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1274 		return true;
1275 
1276 	return false;
1277 }
1278 
1279 static void mld_set_v1_mode(struct inet6_dev *idev)
1280 {
1281 	/* RFC3810, relevant sections:
1282 	 *  - 9.1. Robustness Variable
1283 	 *  - 9.2. Query Interval
1284 	 *  - 9.3. Query Response Interval
1285 	 *  - 9.12. Older Version Querier Present Timeout
1286 	 */
1287 	unsigned long switchback;
1288 
1289 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1290 
1291 	idev->mc_v1_seen = jiffies + switchback;
1292 }
1293 
1294 static void mld_update_qrv(struct inet6_dev *idev,
1295 			   const struct mld2_query *mlh2)
1296 {
1297 	/* RFC3810, relevant sections:
1298 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1299 	 *  - 9.1. Robustness Variable
1300 	 */
1301 
1302 	/* The value of the Robustness Variable MUST NOT be zero,
1303 	 * and SHOULD NOT be one. Catch this here if we ever run
1304 	 * into such a case in future.
1305 	 */
1306 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1307 	WARN_ON(idev->mc_qrv == 0);
1308 
1309 	if (mlh2->mld2q_qrv > 0)
1310 		idev->mc_qrv = mlh2->mld2q_qrv;
1311 
1312 	if (unlikely(idev->mc_qrv < min_qrv)) {
1313 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1314 				     idev->mc_qrv, min_qrv);
1315 		idev->mc_qrv = min_qrv;
1316 	}
1317 }
1318 
1319 static void mld_update_qi(struct inet6_dev *idev,
1320 			  const struct mld2_query *mlh2)
1321 {
1322 	/* RFC3810, relevant sections:
1323 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1324 	 *  - 9.2. Query Interval
1325 	 *  - 9.12. Older Version Querier Present Timeout
1326 	 *    (the [Query Interval] in the last Query received)
1327 	 */
1328 	idev->mc_qi = mldv2_qqi(mlh2) * HZ;
1329 }
1330 
1331 static void mld_update_qri(struct inet6_dev *idev,
1332 			   const struct mld2_query *mlh2)
1333 {
1334 	/* RFC3810, relevant sections:
1335 	 *  - 5.1.3. Maximum Response Code
1336 	 *  - 9.3. Query Response Interval
1337 	 */
1338 	idev->mc_qri = msecs_to_jiffies(mldv2_mrd(mlh2));
1339 }
1340 
1341 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1342 			  unsigned long *max_delay, bool v1_query)
1343 {
1344 	unsigned long mldv1_md;
1345 
1346 	/* Ignore v1 queries */
1347 	if (mld_in_v2_mode_only(idev))
1348 		return -EINVAL;
1349 
1350 	mldv1_md = ntohs(mld->mld_maxdelay);
1351 
1352 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1353 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1354 	 * only works when the exponential algorithm is not being
1355 	 * used (as MLDv1 is unaware of such things).
1356 	 *
1357 	 * According to the RFC author, the MLDv2 implementations
1358 	 * he's aware of all use a MRC < 32768 on start up queries.
1359 	 *
1360 	 * Thus, should we *ever* encounter something else larger
1361 	 * than that, just assume the maximum possible within our
1362 	 * reach.
1363 	 */
1364 	if (!v1_query)
1365 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1366 
1367 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1368 
1369 	/* MLDv1 router present: we need to go into v1 mode *only*
1370 	 * when an MLDv1 query is received as per section 9.12. of
1371 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1372 	 * queries MUST be of exactly 24 octets.
1373 	 */
1374 	if (v1_query)
1375 		mld_set_v1_mode(idev);
1376 
1377 	/* cancel MLDv2 report work */
1378 	mld_gq_stop_work(idev);
1379 	/* cancel the interface change work */
1380 	mld_ifc_stop_work(idev);
1381 	/* clear deleted report items */
1382 	mld_clear_delrec(idev);
1383 
1384 	return 0;
1385 }
1386 
1387 static void mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1388 			   unsigned long *max_delay)
1389 {
1390 	*max_delay = max(msecs_to_jiffies(mldv2_mrd(mld)), 1UL);
1391 
1392 	mld_update_qrv(idev, mld);
1393 	mld_update_qi(idev, mld);
1394 	mld_update_qri(idev, mld);
1395 
1396 	idev->mc_maxdelay = *max_delay;
1397 
1398 	return;
1399 }
1400 
1401 /* called with rcu_read_lock() */
1402 void igmp6_event_query(struct sk_buff *skb)
1403 {
1404 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1405 	bool put = false;
1406 
1407 	if (!idev || idev->dead)
1408 		goto out;
1409 
1410 	spin_lock_bh(&idev->mc_query_lock);
1411 	if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS &&
1412 	    in6_dev_hold_safe(idev)) {
1413 		__skb_queue_tail(&idev->mc_query_queue, skb);
1414 		if (mod_delayed_work(mld_wq, &idev->mc_query_work, 0))
1415 			put = true;
1416 		skb = NULL;
1417 	}
1418 	spin_unlock_bh(&idev->mc_query_lock);
1419 
1420 	if (put)
1421 		in6_dev_put(idev);
1422 out:
1423 	kfree_skb(skb);
1424 }
1425 
1426 static void __mld_query_work(struct sk_buff *skb)
1427 {
1428 	struct mld2_query *mlh2 = NULL;
1429 	unsigned long max_delay;
1430 	struct inet6_dev *idev;
1431 	struct in6_addr group;
1432 	struct ifmcaddr6 *ma;
1433 	struct mld_msg *mld;
1434 	int group_type;
1435 	int mark = 0;
1436 	int len, err;
1437 
1438 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1439 		goto kfree_skb;
1440 
1441 	/* compute payload length excluding extension headers */
1442 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1443 	len -= skb_network_header_len(skb);
1444 
1445 	/* RFC3810 6.2
1446 	 * Upon reception of an MLD message that contains a Query, the node
1447 	 * checks if the source address of the message is a valid link-local
1448 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1449 	 * option is present in the Hop-By-Hop Options header of the IPv6
1450 	 * packet.  If any of these checks fails, the packet is dropped.
1451 	 */
1452 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1453 	    ipv6_hdr(skb)->hop_limit != 1 ||
1454 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1455 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1456 		goto kfree_skb;
1457 
1458 	idev = in6_dev_get(skb->dev);
1459 	if (!idev)
1460 		goto kfree_skb;
1461 
1462 	mld = (struct mld_msg *)icmp6_hdr(skb);
1463 	group = mld->mld_mca;
1464 	group_type = ipv6_addr_type(&group);
1465 
1466 	if (group_type != IPV6_ADDR_ANY &&
1467 	    !(group_type&IPV6_ADDR_MULTICAST))
1468 		goto out;
1469 
1470 	if (len < MLD_V1_QUERY_LEN) {
1471 		goto out;
1472 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1473 		err = mld_process_v1(idev, mld, &max_delay,
1474 				     len == MLD_V1_QUERY_LEN);
1475 		if (err < 0)
1476 			goto out;
1477 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1478 		int srcs_offset = sizeof(struct mld2_query) -
1479 				  sizeof(struct icmp6hdr);
1480 
1481 		if (!pskb_may_pull(skb, srcs_offset))
1482 			goto out;
1483 
1484 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1485 
1486 		mld_process_v2(idev, mlh2, &max_delay);
1487 
1488 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1489 			if (mlh2->mld2q_nsrcs)
1490 				goto out; /* no sources allowed */
1491 
1492 			mld_gq_start_work(idev);
1493 			goto out;
1494 		}
1495 		/* mark sources to include, if group & source-specific */
1496 		if (mlh2->mld2q_nsrcs != 0) {
1497 			if (!pskb_may_pull(skb, srcs_offset +
1498 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1499 				goto out;
1500 
1501 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1502 			mark = 1;
1503 		}
1504 	} else {
1505 		goto out;
1506 	}
1507 
1508 	if (group_type == IPV6_ADDR_ANY) {
1509 		for_each_mc_mclock(idev, ma) {
1510 			igmp6_group_queried(ma, max_delay);
1511 		}
1512 	} else {
1513 		for_each_mc_mclock(idev, ma) {
1514 			unsigned int flags;
1515 
1516 			if (!ipv6_addr_equal(&group, &ma->mca_addr))
1517 				continue;
1518 			flags = ma->mca_flags;
1519 
1520 			if (flags & MAF_TIMER_RUNNING) {
1521 				/* gsquery <- gsquery && mark */
1522 				if (!mark)
1523 					WRITE_ONCE(ma->mca_flags,
1524 						   flags & ~MAF_GSQUERY);
1525 			} else {
1526 				/* gsquery <- mark */
1527 				if (mark)
1528 					WRITE_ONCE(ma->mca_flags,
1529 						   flags | MAF_GSQUERY);
1530 				else
1531 					WRITE_ONCE(ma->mca_flags,
1532 						   flags & ~MAF_GSQUERY);
1533 			}
1534 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1535 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1536 				igmp6_group_queried(ma, max_delay);
1537 			break;
1538 		}
1539 	}
1540 
1541 out:
1542 	in6_dev_put(idev);
1543 kfree_skb:
1544 	consume_skb(skb);
1545 }
1546 
1547 static void mld_query_work(struct work_struct *work)
1548 {
1549 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1550 					      struct inet6_dev,
1551 					      mc_query_work);
1552 	struct sk_buff_head q;
1553 	struct sk_buff *skb;
1554 	bool rework = false;
1555 	int cnt = 0;
1556 
1557 	skb_queue_head_init(&q);
1558 
1559 	spin_lock_bh(&idev->mc_query_lock);
1560 	while ((skb = __skb_dequeue(&idev->mc_query_queue))) {
1561 		__skb_queue_tail(&q, skb);
1562 
1563 		if (++cnt >= MLD_MAX_QUEUE) {
1564 			rework = true;
1565 			break;
1566 		}
1567 	}
1568 	spin_unlock_bh(&idev->mc_query_lock);
1569 
1570 	mutex_lock(&idev->mc_lock);
1571 	while ((skb = __skb_dequeue(&q)))
1572 		__mld_query_work(skb);
1573 	mutex_unlock(&idev->mc_lock);
1574 
1575 	if (rework && queue_delayed_work(mld_wq, &idev->mc_query_work, 0))
1576 		return;
1577 
1578 	in6_dev_put(idev);
1579 }
1580 
1581 /* called with rcu_read_lock() */
1582 void igmp6_event_report(struct sk_buff *skb)
1583 {
1584 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1585 	bool put = false;
1586 
1587 	if (!idev || idev->dead)
1588 		goto out;
1589 
1590 	spin_lock_bh(&idev->mc_report_lock);
1591 	if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS &&
1592 	    in6_dev_hold_safe(idev)) {
1593 		__skb_queue_tail(&idev->mc_report_queue, skb);
1594 		if (mod_delayed_work(mld_wq, &idev->mc_report_work, 0))
1595 			put = true;
1596 		skb = NULL;
1597 	}
1598 	spin_unlock_bh(&idev->mc_report_lock);
1599 
1600 	if (put)
1601 		in6_dev_put(idev);
1602 out:
1603 	kfree_skb(skb);
1604 }
1605 
1606 static void __mld_report_work(struct sk_buff *skb)
1607 {
1608 	struct inet6_dev *idev;
1609 	struct ifmcaddr6 *ma;
1610 	struct mld_msg *mld;
1611 	int addr_type;
1612 
1613 	/* Our own report looped back. Ignore it. */
1614 	if (skb->pkt_type == PACKET_LOOPBACK)
1615 		goto kfree_skb;
1616 
1617 	/* send our report if the MC router may not have heard this report */
1618 	if (skb->pkt_type != PACKET_MULTICAST &&
1619 	    skb->pkt_type != PACKET_BROADCAST)
1620 		goto kfree_skb;
1621 
1622 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1623 		goto kfree_skb;
1624 
1625 	mld = (struct mld_msg *)icmp6_hdr(skb);
1626 
1627 	/* Drop reports with not link local source */
1628 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1629 	if (addr_type != IPV6_ADDR_ANY &&
1630 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1631 		goto kfree_skb;
1632 
1633 	idev = in6_dev_get(skb->dev);
1634 	if (!idev)
1635 		goto kfree_skb;
1636 
1637 	/*
1638 	 *	Cancel the work for this group
1639 	 */
1640 
1641 	for_each_mc_mclock(idev, ma) {
1642 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1643 			if (cancel_delayed_work(&ma->mca_work))
1644 				refcount_dec(&ma->mca_refcnt);
1645 			WRITE_ONCE(ma->mca_flags,
1646 				   ma->mca_flags & ~(MAF_LAST_REPORTER |
1647 						     MAF_TIMER_RUNNING));
1648 			break;
1649 		}
1650 	}
1651 
1652 	in6_dev_put(idev);
1653 kfree_skb:
1654 	consume_skb(skb);
1655 }
1656 
1657 static void mld_report_work(struct work_struct *work)
1658 {
1659 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1660 					      struct inet6_dev,
1661 					      mc_report_work);
1662 	struct sk_buff_head q;
1663 	struct sk_buff *skb;
1664 	bool rework = false;
1665 	int cnt = 0;
1666 
1667 	skb_queue_head_init(&q);
1668 	spin_lock_bh(&idev->mc_report_lock);
1669 	while ((skb = __skb_dequeue(&idev->mc_report_queue))) {
1670 		__skb_queue_tail(&q, skb);
1671 
1672 		if (++cnt >= MLD_MAX_QUEUE) {
1673 			rework = true;
1674 			break;
1675 		}
1676 	}
1677 	spin_unlock_bh(&idev->mc_report_lock);
1678 
1679 	mutex_lock(&idev->mc_lock);
1680 	while ((skb = __skb_dequeue(&q)))
1681 		__mld_report_work(skb);
1682 	mutex_unlock(&idev->mc_lock);
1683 
1684 	if (rework && queue_delayed_work(mld_wq, &idev->mc_report_work, 0))
1685 		return;
1686 
1687 	in6_dev_put(idev);
1688 }
1689 
1690 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1691 		  int gdeleted, int sdeleted)
1692 {
1693 	switch (type) {
1694 	case MLD2_MODE_IS_INCLUDE:
1695 	case MLD2_MODE_IS_EXCLUDE:
1696 		if (gdeleted || sdeleted)
1697 			return false;
1698 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1699 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1700 				return true;
1701 			/* don't include if this source is excluded
1702 			 * in all filters
1703 			 */
1704 			if (psf->sf_count[MCAST_INCLUDE])
1705 				return type == MLD2_MODE_IS_INCLUDE;
1706 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1707 				psf->sf_count[MCAST_EXCLUDE];
1708 		}
1709 		return false;
1710 	case MLD2_CHANGE_TO_INCLUDE:
1711 		if (gdeleted || sdeleted)
1712 			return false;
1713 		return psf->sf_count[MCAST_INCLUDE] != 0;
1714 	case MLD2_CHANGE_TO_EXCLUDE:
1715 		if (gdeleted || sdeleted)
1716 			return false;
1717 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1718 		    psf->sf_count[MCAST_INCLUDE])
1719 			return false;
1720 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1721 			psf->sf_count[MCAST_EXCLUDE];
1722 	case MLD2_ALLOW_NEW_SOURCES:
1723 		if (gdeleted || !psf->sf_crcount)
1724 			return false;
1725 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1726 	case MLD2_BLOCK_OLD_SOURCES:
1727 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1728 			return gdeleted || (psf->sf_crcount && sdeleted);
1729 		return psf->sf_crcount && !gdeleted && !sdeleted;
1730 	}
1731 	return false;
1732 }
1733 
1734 static int
1735 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1736 {
1737 	struct ip6_sf_list *psf;
1738 	int scount = 0;
1739 
1740 	for_each_psf_mclock(pmc, psf) {
1741 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1742 			continue;
1743 		scount++;
1744 	}
1745 	return scount;
1746 }
1747 
1748 static void ip6_mc_hdr(const struct sock *sk, struct sk_buff *skb,
1749 		       struct net_device *dev, const struct in6_addr *saddr,
1750 		       const struct in6_addr *daddr, int proto, int len)
1751 {
1752 	struct ipv6hdr *hdr;
1753 
1754 	skb->protocol = htons(ETH_P_IPV6);
1755 	skb->dev = dev;
1756 
1757 	skb_reset_network_header(skb);
1758 	skb_put(skb, sizeof(struct ipv6hdr));
1759 	hdr = ipv6_hdr(skb);
1760 
1761 	ip6_flow_hdr(hdr, 0, 0);
1762 
1763 	hdr->payload_len = htons(len);
1764 	hdr->nexthdr = proto;
1765 	hdr->hop_limit = READ_ONCE(inet6_sk(sk)->hop_limit);
1766 
1767 	hdr->saddr = *saddr;
1768 	hdr->daddr = *daddr;
1769 }
1770 
1771 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1772 {
1773 	u8 ra[8] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT,
1774 		     2, 0, 0, IPV6_TLV_PADN, 0 };
1775 	struct net_device *dev = idev->dev;
1776 	int hlen = LL_RESERVED_SPACE(dev);
1777 	int tlen = dev->needed_tailroom;
1778 	const struct in6_addr *saddr;
1779 	struct in6_addr addr_buf;
1780 	struct mld2_report *pmr;
1781 	struct sk_buff *skb;
1782 	unsigned int size;
1783 	struct sock *sk;
1784 	struct net *net;
1785 
1786 	/* we assume size > sizeof(ra) here
1787 	 * Also try to not allocate high-order pages for big MTU
1788 	 */
1789 	size = min_t(int, mtu, PAGE_SIZE / 2) + hlen + tlen;
1790 	skb = alloc_skb(size, GFP_KERNEL);
1791 	if (!skb)
1792 		return NULL;
1793 
1794 	skb->priority = TC_PRIO_CONTROL;
1795 	skb_reserve(skb, hlen);
1796 	skb_tailroom_reserve(skb, mtu, tlen);
1797 
1798 	rcu_read_lock();
1799 
1800 	net = dev_net_rcu(dev);
1801 	sk = net->ipv6.igmp_sk;
1802 	skb_set_owner_w(skb, sk);
1803 
1804 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1805 		/* <draft-ietf-magma-mld-source-05.txt>:
1806 		 * use unspecified address as the source address
1807 		 * when a valid link-local address is not available.
1808 		 */
1809 		saddr = &in6addr_any;
1810 	} else
1811 		saddr = &addr_buf;
1812 
1813 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1814 
1815 	rcu_read_unlock();
1816 
1817 	skb_put_data(skb, ra, sizeof(ra));
1818 
1819 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1820 	skb_put(skb, sizeof(*pmr));
1821 	pmr = (struct mld2_report *)skb_transport_header(skb);
1822 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1823 	pmr->mld2r_resv1 = 0;
1824 	pmr->mld2r_cksum = 0;
1825 	pmr->mld2r_resv2 = 0;
1826 	pmr->mld2r_ngrec = 0;
1827 	return skb;
1828 }
1829 
1830 static void mld_sendpack(struct sk_buff *skb)
1831 {
1832 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1833 	struct mld2_report *pmr =
1834 			      (struct mld2_report *)skb_transport_header(skb);
1835 	int payload_len, mldlen;
1836 	struct inet6_dev *idev;
1837 	struct net *net = dev_net(skb->dev);
1838 	int err;
1839 	struct flowi6 fl6;
1840 	struct dst_entry *dst;
1841 
1842 	rcu_read_lock();
1843 	idev = __in6_dev_get(skb->dev);
1844 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
1845 
1846 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1847 		sizeof(*pip6);
1848 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1849 	pip6->payload_len = htons(payload_len);
1850 
1851 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1852 					   IPPROTO_ICMPV6,
1853 					   csum_partial(skb_transport_header(skb),
1854 							mldlen, 0));
1855 
1856 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1857 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1858 			 skb->dev->ifindex);
1859 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1860 
1861 	err = 0;
1862 	if (IS_ERR(dst)) {
1863 		err = PTR_ERR(dst);
1864 		dst = NULL;
1865 	}
1866 	skb_dst_set(skb, dst);
1867 	if (err)
1868 		goto err_out;
1869 
1870 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1871 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1872 		      dst_output);
1873 out:
1874 	if (!err) {
1875 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1876 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1877 	} else {
1878 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1879 	}
1880 
1881 	rcu_read_unlock();
1882 	return;
1883 
1884 err_out:
1885 	kfree_skb(skb);
1886 	goto out;
1887 }
1888 
1889 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1890 {
1891 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1892 }
1893 
1894 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1895 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1896 {
1897 	struct mld2_report *pmr;
1898 	struct mld2_grec *pgr;
1899 
1900 	if (!skb) {
1901 		skb = mld_newpack(pmc->idev, mtu);
1902 		if (!skb)
1903 			return NULL;
1904 	}
1905 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1906 	pgr->grec_type = type;
1907 	pgr->grec_auxwords = 0;
1908 	pgr->grec_nsrcs = 0;
1909 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1910 	pmr = (struct mld2_report *)skb_transport_header(skb);
1911 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1912 	*ppgr = pgr;
1913 	return skb;
1914 }
1915 
1916 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1917 
1918 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1919 				int type, int gdeleted, int sdeleted,
1920 				int crsend)
1921 {
1922 	struct ip6_sf_list *psf, *psf_prev, *psf_next;
1923 	int scount, stotal, first, isquery, truncate;
1924 	struct ip6_sf_list __rcu **psf_list;
1925 	struct inet6_dev *idev = pmc->idev;
1926 	struct net_device *dev = idev->dev;
1927 	struct mld2_grec *pgr = NULL;
1928 	struct mld2_report *pmr;
1929 	unsigned int mtu;
1930 
1931 	mc_assert_locked(idev);
1932 
1933 	if (pmc->mca_flags & MAF_NOREPORT)
1934 		return skb;
1935 
1936 	mtu = READ_ONCE(dev->mtu);
1937 	if (mtu < IPV6_MIN_MTU)
1938 		return skb;
1939 
1940 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1941 		  type == MLD2_MODE_IS_EXCLUDE;
1942 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1943 		    type == MLD2_CHANGE_TO_EXCLUDE;
1944 
1945 	stotal = scount = 0;
1946 
1947 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1948 
1949 	if (!rcu_access_pointer(*psf_list))
1950 		goto empty_source;
1951 
1952 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1953 
1954 	/* EX and TO_EX get a fresh packet, if needed */
1955 	if (truncate) {
1956 		if (pmr && pmr->mld2r_ngrec &&
1957 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1958 			if (skb)
1959 				mld_sendpack(skb);
1960 			skb = mld_newpack(idev, mtu);
1961 		}
1962 	}
1963 	first = 1;
1964 	psf_prev = NULL;
1965 	for (psf = mc_dereference(*psf_list, idev);
1966 	     psf;
1967 	     psf = psf_next) {
1968 		struct in6_addr *psrc;
1969 
1970 		psf_next = mc_dereference(psf->sf_next, idev);
1971 
1972 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1973 			psf_prev = psf;
1974 			continue;
1975 		}
1976 
1977 		/* Based on RFC3810 6.1. Should not send source-list change
1978 		 * records when there is a filter mode change.
1979 		 */
1980 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1981 		     (!gdeleted && pmc->mca_crcount)) &&
1982 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1983 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1984 			goto decrease_sf_crcount;
1985 
1986 		/* clear marks on query responses */
1987 		if (isquery)
1988 			psf->sf_gsresp = 0;
1989 
1990 		if (AVAILABLE(skb) < sizeof(*psrc) +
1991 		    first*sizeof(struct mld2_grec)) {
1992 			if (truncate && !first)
1993 				break;	 /* truncate these */
1994 			if (pgr)
1995 				pgr->grec_nsrcs = htons(scount);
1996 			if (skb)
1997 				mld_sendpack(skb);
1998 			skb = mld_newpack(idev, mtu);
1999 			first = 1;
2000 			scount = 0;
2001 		}
2002 		if (first) {
2003 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
2004 			first = 0;
2005 		}
2006 		if (!skb)
2007 			return NULL;
2008 		psrc = skb_put(skb, sizeof(*psrc));
2009 		*psrc = psf->sf_addr;
2010 		scount++; stotal++;
2011 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
2012 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
2013 decrease_sf_crcount:
2014 			psf->sf_crcount--;
2015 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
2016 				if (psf_prev)
2017 					rcu_assign_pointer(psf_prev->sf_next,
2018 							   mc_dereference(psf->sf_next, idev));
2019 				else
2020 					rcu_assign_pointer(*psf_list,
2021 							   mc_dereference(psf->sf_next, idev));
2022 				kfree_rcu(psf, rcu);
2023 				continue;
2024 			}
2025 		}
2026 		psf_prev = psf;
2027 	}
2028 
2029 empty_source:
2030 	if (!stotal) {
2031 		if (type == MLD2_ALLOW_NEW_SOURCES ||
2032 		    type == MLD2_BLOCK_OLD_SOURCES)
2033 			return skb;
2034 		if (pmc->mca_crcount || isquery || crsend) {
2035 			/* make sure we have room for group header */
2036 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
2037 				mld_sendpack(skb);
2038 				skb = NULL; /* add_grhead will get a new one */
2039 			}
2040 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
2041 		}
2042 	}
2043 	if (pgr)
2044 		pgr->grec_nsrcs = htons(scount);
2045 
2046 	if (isquery) {
2047 		/* clear query state */
2048 		WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
2049 	}
2050 	return skb;
2051 }
2052 
2053 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
2054 {
2055 	struct sk_buff *skb = NULL;
2056 	int type;
2057 
2058 	mc_assert_locked(idev);
2059 
2060 	if (!pmc) {
2061 		for_each_mc_mclock(idev, pmc) {
2062 			if (pmc->mca_flags & MAF_NOREPORT)
2063 				continue;
2064 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
2065 				type = MLD2_MODE_IS_EXCLUDE;
2066 			else
2067 				type = MLD2_MODE_IS_INCLUDE;
2068 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2069 		}
2070 	} else {
2071 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2072 			type = MLD2_MODE_IS_EXCLUDE;
2073 		else
2074 			type = MLD2_MODE_IS_INCLUDE;
2075 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2076 	}
2077 	if (skb)
2078 		mld_sendpack(skb);
2079 }
2080 
2081 /* remove zero-count source records from a source filter list */
2082 static void mld_clear_zeros(struct ip6_sf_list __rcu **ppsf, struct inet6_dev *idev)
2083 {
2084 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
2085 
2086 	psf_prev = NULL;
2087 	for (psf = mc_dereference(*ppsf, idev);
2088 	     psf;
2089 	     psf = psf_next) {
2090 		psf_next = mc_dereference(psf->sf_next, idev);
2091 		if (psf->sf_crcount == 0) {
2092 			if (psf_prev)
2093 				rcu_assign_pointer(psf_prev->sf_next,
2094 						   mc_dereference(psf->sf_next, idev));
2095 			else
2096 				rcu_assign_pointer(*ppsf,
2097 						   mc_dereference(psf->sf_next, idev));
2098 			kfree_rcu(psf, rcu);
2099 		} else {
2100 			psf_prev = psf;
2101 		}
2102 	}
2103 }
2104 
2105 static void mld_send_cr(struct inet6_dev *idev)
2106 {
2107 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
2108 	struct sk_buff *skb = NULL;
2109 	int type, dtype;
2110 
2111 	/* deleted MCA's */
2112 	pmc_prev = NULL;
2113 	for (pmc = mc_dereference(idev->mc_tomb, idev);
2114 	     pmc;
2115 	     pmc = pmc_next) {
2116 		pmc_next = mc_dereference(pmc->next, idev);
2117 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
2118 			type = MLD2_BLOCK_OLD_SOURCES;
2119 			dtype = MLD2_BLOCK_OLD_SOURCES;
2120 			skb = add_grec(skb, pmc, type, 1, 0, 0);
2121 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
2122 		}
2123 		if (pmc->mca_crcount) {
2124 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
2125 				type = MLD2_CHANGE_TO_INCLUDE;
2126 				skb = add_grec(skb, pmc, type, 1, 0, 0);
2127 			}
2128 			pmc->mca_crcount--;
2129 			if (pmc->mca_crcount == 0) {
2130 				mld_clear_zeros(&pmc->mca_tomb, idev);
2131 				mld_clear_zeros(&pmc->mca_sources, idev);
2132 			}
2133 		}
2134 		if (pmc->mca_crcount == 0 &&
2135 		    !rcu_access_pointer(pmc->mca_tomb) &&
2136 		    !rcu_access_pointer(pmc->mca_sources)) {
2137 			if (pmc_prev)
2138 				rcu_assign_pointer(pmc_prev->next, pmc_next);
2139 			else
2140 				rcu_assign_pointer(idev->mc_tomb, pmc_next);
2141 			in6_dev_put(pmc->idev);
2142 			kfree_rcu(pmc, rcu);
2143 		} else
2144 			pmc_prev = pmc;
2145 	}
2146 
2147 	/* change recs */
2148 	for_each_mc_mclock(idev, pmc) {
2149 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2150 			type = MLD2_BLOCK_OLD_SOURCES;
2151 			dtype = MLD2_ALLOW_NEW_SOURCES;
2152 		} else {
2153 			type = MLD2_ALLOW_NEW_SOURCES;
2154 			dtype = MLD2_BLOCK_OLD_SOURCES;
2155 		}
2156 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2157 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
2158 
2159 		/* filter mode changes */
2160 		if (pmc->mca_crcount) {
2161 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
2162 				type = MLD2_CHANGE_TO_EXCLUDE;
2163 			else
2164 				type = MLD2_CHANGE_TO_INCLUDE;
2165 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2166 			pmc->mca_crcount--;
2167 		}
2168 	}
2169 	if (!skb)
2170 		return;
2171 	(void) mld_sendpack(skb);
2172 }
2173 
2174 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
2175 {
2176 	const struct in6_addr *snd_addr, *saddr;
2177 	int err, len, payload_len, full_len;
2178 	struct in6_addr addr_buf;
2179 	struct inet6_dev *idev;
2180 	struct sk_buff *skb;
2181 	struct mld_msg *hdr;
2182 	int hlen = LL_RESERVED_SPACE(dev);
2183 	int tlen = dev->needed_tailroom;
2184 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
2185 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
2186 		     IPV6_TLV_PADN, 0 };
2187 	struct dst_entry *dst;
2188 	struct flowi6 fl6;
2189 	struct net *net;
2190 	struct sock *sk;
2191 
2192 	if (type == ICMPV6_MGM_REDUCTION)
2193 		snd_addr = &in6addr_linklocal_allrouters;
2194 	else
2195 		snd_addr = addr;
2196 
2197 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2198 	payload_len = len + sizeof(ra);
2199 	full_len = sizeof(struct ipv6hdr) + payload_len;
2200 
2201 	skb = alloc_skb(hlen + tlen + full_len, GFP_KERNEL);
2202 
2203 	rcu_read_lock();
2204 
2205 	net = dev_net_rcu(dev);
2206 	idev = __in6_dev_get(dev);
2207 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
2208 	if (!skb) {
2209 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2210 		rcu_read_unlock();
2211 		return;
2212 	}
2213 	sk = net->ipv6.igmp_sk;
2214 	skb_set_owner_w(skb, sk);
2215 
2216 	skb->priority = TC_PRIO_CONTROL;
2217 	skb_reserve(skb, hlen);
2218 
2219 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2220 		/* <draft-ietf-magma-mld-source-05.txt>:
2221 		 * use unspecified address as the source address
2222 		 * when a valid link-local address is not available.
2223 		 */
2224 		saddr = &in6addr_any;
2225 	} else
2226 		saddr = &addr_buf;
2227 
2228 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2229 
2230 	skb_put_data(skb, ra, sizeof(ra));
2231 
2232 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2233 	hdr->mld_type = type;
2234 	hdr->mld_mca = *addr;
2235 
2236 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2237 					 IPPROTO_ICMPV6,
2238 					 csum_partial(hdr, len, 0));
2239 
2240 	icmpv6_flow_init(sk, &fl6, type,
2241 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2242 			 skb->dev->ifindex);
2243 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2244 	if (IS_ERR(dst)) {
2245 		err = PTR_ERR(dst);
2246 		goto err_out;
2247 	}
2248 
2249 	skb_dst_set(skb, dst);
2250 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2251 		      net, sk, skb, NULL, skb->dev,
2252 		      dst_output);
2253 out:
2254 	if (!err) {
2255 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2256 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2257 	} else
2258 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2259 
2260 	rcu_read_unlock();
2261 	return;
2262 
2263 err_out:
2264 	kfree_skb(skb);
2265 	goto out;
2266 }
2267 
2268 static void mld_send_initial_cr(struct inet6_dev *idev)
2269 {
2270 	struct ifmcaddr6 *pmc;
2271 	struct sk_buff *skb;
2272 	int type;
2273 
2274 	mc_assert_locked(idev);
2275 
2276 	if (mld_in_v1_mode(idev))
2277 		return;
2278 
2279 	skb = NULL;
2280 	for_each_mc_mclock(idev, pmc) {
2281 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2282 			type = MLD2_CHANGE_TO_EXCLUDE;
2283 		else
2284 			type = MLD2_ALLOW_NEW_SOURCES;
2285 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2286 	}
2287 	if (skb)
2288 		mld_sendpack(skb);
2289 }
2290 
2291 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2292 {
2293 	mutex_lock(&idev->mc_lock);
2294 	idev->mc_dad_count = idev->mc_qrv;
2295 	if (idev->mc_dad_count) {
2296 		mld_send_initial_cr(idev);
2297 		idev->mc_dad_count--;
2298 		if (idev->mc_dad_count)
2299 			mld_dad_start_work(idev,
2300 					   unsolicited_report_interval(idev));
2301 	}
2302 	mutex_unlock(&idev->mc_lock);
2303 }
2304 
2305 static void mld_dad_work(struct work_struct *work)
2306 {
2307 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2308 					      struct inet6_dev,
2309 					      mc_dad_work);
2310 	mutex_lock(&idev->mc_lock);
2311 	mld_send_initial_cr(idev);
2312 	if (idev->mc_dad_count) {
2313 		idev->mc_dad_count--;
2314 		if (idev->mc_dad_count)
2315 			mld_dad_start_work(idev,
2316 					   unsolicited_report_interval(idev));
2317 	}
2318 	mutex_unlock(&idev->mc_lock);
2319 	in6_dev_put(idev);
2320 }
2321 
2322 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2323 			   const struct in6_addr *psfsrc)
2324 {
2325 	struct ip6_sf_list *psf, *psf_prev;
2326 	int rv = 0;
2327 
2328 	mc_assert_locked(pmc->idev);
2329 
2330 	psf_prev = NULL;
2331 	for_each_psf_mclock(pmc, psf) {
2332 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2333 			break;
2334 		psf_prev = psf;
2335 	}
2336 	if (!psf || psf->sf_count[sfmode] == 0) {
2337 		/* source filter not found, or count wrong =>  bug */
2338 		return -ESRCH;
2339 	}
2340 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] - 1);
2341 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2342 		struct inet6_dev *idev = pmc->idev;
2343 
2344 		/* no more filters for this source */
2345 		if (psf_prev)
2346 			rcu_assign_pointer(psf_prev->sf_next,
2347 					   mc_dereference(psf->sf_next, idev));
2348 		else
2349 			rcu_assign_pointer(pmc->mca_sources,
2350 					   mc_dereference(psf->sf_next, idev));
2351 
2352 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2353 		    !mld_in_v1_mode(idev)) {
2354 			psf->sf_crcount = idev->mc_qrv;
2355 			rcu_assign_pointer(psf->sf_next,
2356 					   mc_dereference(pmc->mca_tomb, idev));
2357 			rcu_assign_pointer(pmc->mca_tomb, psf);
2358 			rv = 1;
2359 		} else {
2360 			kfree_rcu(psf, rcu);
2361 		}
2362 	}
2363 	return rv;
2364 }
2365 
2366 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2367 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2368 			  int delta)
2369 {
2370 	struct ifmcaddr6 *pmc;
2371 	int	changerec = 0;
2372 	int	i, err;
2373 
2374 	if (!idev)
2375 		return -ENODEV;
2376 
2377 	mc_assert_locked(idev);
2378 
2379 	for_each_mc_mclock(idev, pmc) {
2380 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2381 			break;
2382 	}
2383 	if (!pmc)
2384 		return -ESRCH;
2385 
2386 	sf_markstate(pmc);
2387 	if (!delta) {
2388 		if (!pmc->mca_sfcount[sfmode])
2389 			return -EINVAL;
2390 
2391 		pmc->mca_sfcount[sfmode]--;
2392 	}
2393 	err = 0;
2394 	for (i = 0; i < sfcount; i++) {
2395 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2396 
2397 		changerec |= rv > 0;
2398 		if (!err && rv < 0)
2399 			err = rv;
2400 	}
2401 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2402 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2403 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2404 		struct ip6_sf_list *psf;
2405 
2406 		/* filter mode change */
2407 		pmc->mca_sfmode = MCAST_INCLUDE;
2408 		pmc->mca_crcount = idev->mc_qrv;
2409 		idev->mc_ifc_count = pmc->mca_crcount;
2410 		for_each_psf_mclock(pmc, psf)
2411 			psf->sf_crcount = 0;
2412 		mld_ifc_event(pmc->idev);
2413 	} else if (sf_setstate(pmc) || changerec) {
2414 		mld_ifc_event(pmc->idev);
2415 	}
2416 
2417 	return err;
2418 }
2419 
2420 /* Add multicast single-source filter to the interface list */
2421 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2422 			   const struct in6_addr *psfsrc)
2423 {
2424 	struct ip6_sf_list *psf, *psf_prev;
2425 
2426 	mc_assert_locked(pmc->idev);
2427 
2428 	psf_prev = NULL;
2429 	for_each_psf_mclock(pmc, psf) {
2430 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2431 			break;
2432 		psf_prev = psf;
2433 	}
2434 	if (!psf) {
2435 		psf = kzalloc_obj(*psf);
2436 		if (!psf)
2437 			return -ENOBUFS;
2438 
2439 		psf->sf_addr = *psfsrc;
2440 		if (psf_prev) {
2441 			rcu_assign_pointer(psf_prev->sf_next, psf);
2442 		} else {
2443 			rcu_assign_pointer(pmc->mca_sources, psf);
2444 		}
2445 	}
2446 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] + 1);
2447 	return 0;
2448 }
2449 
2450 static void sf_markstate(struct ifmcaddr6 *pmc)
2451 {
2452 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2453 	struct ip6_sf_list *psf;
2454 
2455 	mc_assert_locked(pmc->idev);
2456 
2457 	for_each_psf_mclock(pmc, psf) {
2458 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2459 			psf->sf_oldin = mca_xcount ==
2460 				psf->sf_count[MCAST_EXCLUDE] &&
2461 				!psf->sf_count[MCAST_INCLUDE];
2462 		} else {
2463 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2464 		}
2465 	}
2466 }
2467 
2468 static int sf_setstate(struct ifmcaddr6 *pmc)
2469 {
2470 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2471 	struct ip6_sf_list *psf, *dpsf;
2472 	int qrv = pmc->idev->mc_qrv;
2473 	int new_in, rv;
2474 
2475 	mc_assert_locked(pmc->idev);
2476 
2477 	rv = 0;
2478 	for_each_psf_mclock(pmc, psf) {
2479 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2480 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2481 				!psf->sf_count[MCAST_INCLUDE];
2482 		} else
2483 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2484 		if (new_in) {
2485 			if (!psf->sf_oldin) {
2486 				struct ip6_sf_list *prev = NULL;
2487 
2488 				for_each_psf_tomb(pmc, dpsf) {
2489 					if (ipv6_addr_equal(&dpsf->sf_addr,
2490 					    &psf->sf_addr))
2491 						break;
2492 					prev = dpsf;
2493 				}
2494 				if (dpsf) {
2495 					if (prev)
2496 						rcu_assign_pointer(prev->sf_next,
2497 								   mc_dereference(dpsf->sf_next,
2498 										  pmc->idev));
2499 					else
2500 						rcu_assign_pointer(pmc->mca_tomb,
2501 								   mc_dereference(dpsf->sf_next,
2502 										  pmc->idev));
2503 					kfree_rcu(dpsf, rcu);
2504 				}
2505 				psf->sf_crcount = qrv;
2506 				rv++;
2507 			}
2508 		} else if (psf->sf_oldin) {
2509 			psf->sf_crcount = 0;
2510 			/*
2511 			 * add or update "delete" records if an active filter
2512 			 * is now inactive
2513 			 */
2514 
2515 			for_each_psf_tomb(pmc, dpsf)
2516 				if (ipv6_addr_equal(&dpsf->sf_addr,
2517 				    &psf->sf_addr))
2518 					break;
2519 			if (!dpsf) {
2520 				dpsf = kmalloc_obj(*dpsf);
2521 				if (!dpsf)
2522 					continue;
2523 				*dpsf = *psf;
2524 				rcu_assign_pointer(dpsf->sf_next,
2525 						   mc_dereference(pmc->mca_tomb, pmc->idev));
2526 				rcu_assign_pointer(pmc->mca_tomb, dpsf);
2527 			}
2528 			dpsf->sf_crcount = qrv;
2529 			rv++;
2530 		}
2531 	}
2532 	return rv;
2533 }
2534 
2535 /* Add multicast source filter list to the interface list */
2536 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2537 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2538 			  int delta)
2539 {
2540 	struct ifmcaddr6 *pmc;
2541 	int	isexclude;
2542 	int	i, err;
2543 
2544 	if (!idev)
2545 		return -ENODEV;
2546 
2547 	mc_assert_locked(idev);
2548 
2549 	for_each_mc_mclock(idev, pmc) {
2550 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2551 			break;
2552 	}
2553 	if (!pmc)
2554 		return -ESRCH;
2555 
2556 	sf_markstate(pmc);
2557 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2558 	if (!delta)
2559 		WRITE_ONCE(pmc->mca_sfcount[sfmode],
2560 			   pmc->mca_sfcount[sfmode] + 1);
2561 	err = 0;
2562 	for (i = 0; i < sfcount; i++) {
2563 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2564 		if (err)
2565 			break;
2566 	}
2567 	if (err) {
2568 		int j;
2569 
2570 		if (!delta)
2571 			WRITE_ONCE(pmc->mca_sfcount[sfmode],
2572 				   pmc->mca_sfcount[sfmode] - 1);
2573 		for (j = 0; j < i; j++)
2574 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2575 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2576 		struct ip6_sf_list *psf;
2577 
2578 		/* filter mode change */
2579 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2580 			pmc->mca_sfmode = MCAST_EXCLUDE;
2581 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2582 			pmc->mca_sfmode = MCAST_INCLUDE;
2583 		/* else no filters; keep old mode for reports */
2584 
2585 		pmc->mca_crcount = idev->mc_qrv;
2586 		idev->mc_ifc_count = pmc->mca_crcount;
2587 		for_each_psf_mclock(pmc, psf)
2588 			psf->sf_crcount = 0;
2589 		mld_ifc_event(idev);
2590 	} else if (sf_setstate(pmc)) {
2591 		mld_ifc_event(idev);
2592 	}
2593 	return err;
2594 }
2595 
2596 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2597 {
2598 	struct ip6_sf_list *psf, *nextpsf;
2599 
2600 	mc_assert_locked(pmc->idev);
2601 
2602 	for (psf = mc_dereference(pmc->mca_tomb, pmc->idev);
2603 	     psf;
2604 	     psf = nextpsf) {
2605 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2606 		kfree_rcu(psf, rcu);
2607 	}
2608 	RCU_INIT_POINTER(pmc->mca_tomb, NULL);
2609 	for (psf = mc_dereference(pmc->mca_sources, pmc->idev);
2610 	     psf;
2611 	     psf = nextpsf) {
2612 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2613 		kfree_rcu(psf, rcu);
2614 	}
2615 	RCU_INIT_POINTER(pmc->mca_sources, NULL);
2616 	pmc->mca_sfmode = MCAST_EXCLUDE;
2617 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2618 	/* Paired with the READ_ONCE() from ipv6_chk_mcast_addr() */
2619 	WRITE_ONCE(pmc->mca_sfcount[MCAST_EXCLUDE], 1);
2620 }
2621 
2622 static void igmp6_join_group(struct ifmcaddr6 *ma)
2623 {
2624 	unsigned long delay;
2625 
2626 	mc_assert_locked(ma->idev);
2627 
2628 	if (ma->mca_flags & MAF_NOREPORT)
2629 		return;
2630 
2631 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2632 
2633 	delay = get_random_u32_below(unsolicited_report_interval(ma->idev));
2634 
2635 	if (cancel_delayed_work(&ma->mca_work)) {
2636 		refcount_dec(&ma->mca_refcnt);
2637 		delay = ma->mca_work.timer.expires - jiffies;
2638 	}
2639 
2640 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
2641 		refcount_inc(&ma->mca_refcnt);
2642 	WRITE_ONCE(ma->mca_flags, ma->mca_flags |
2643 		   MAF_TIMER_RUNNING | MAF_LAST_REPORTER);
2644 }
2645 
2646 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2647 			    struct inet6_dev *idev)
2648 {
2649 	struct ip6_sf_socklist *psl;
2650 	int err;
2651 
2652 	psl = sock_dereference(iml->sflist, sk);
2653 
2654 	if (idev)
2655 		mutex_lock(&idev->mc_lock);
2656 
2657 	if (!psl) {
2658 		/* any-source empty exclude case */
2659 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2660 	} else {
2661 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2662 				     psl->sl_count, psl->sl_addr, 0);
2663 		RCU_INIT_POINTER(iml->sflist, NULL);
2664 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2665 			   &sk->sk_omem_alloc);
2666 		kfree_rcu(psl, rcu);
2667 	}
2668 
2669 	if (idev)
2670 		mutex_unlock(&idev->mc_lock);
2671 
2672 	return err;
2673 }
2674 
2675 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2676 {
2677 	mc_assert_locked(ma->idev);
2678 
2679 	if (mld_in_v1_mode(ma->idev)) {
2680 		if (ma->mca_flags & MAF_LAST_REPORTER) {
2681 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2682 				ICMPV6_MGM_REDUCTION);
2683 		}
2684 	} else {
2685 		mld_add_delrec(ma->idev, ma);
2686 		mld_ifc_event(ma->idev);
2687 	}
2688 }
2689 
2690 static void mld_gq_work(struct work_struct *work)
2691 {
2692 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2693 					      struct inet6_dev,
2694 					      mc_gq_work);
2695 
2696 	mutex_lock(&idev->mc_lock);
2697 	mld_send_report(idev, NULL);
2698 	idev->mc_gq_running = 0;
2699 	mutex_unlock(&idev->mc_lock);
2700 
2701 	in6_dev_put(idev);
2702 }
2703 
2704 static void mld_ifc_work(struct work_struct *work)
2705 {
2706 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2707 					      struct inet6_dev,
2708 					      mc_ifc_work);
2709 
2710 	mutex_lock(&idev->mc_lock);
2711 	mld_send_cr(idev);
2712 
2713 	if (idev->mc_ifc_count) {
2714 		idev->mc_ifc_count--;
2715 		if (idev->mc_ifc_count)
2716 			mld_ifc_start_work(idev,
2717 					   unsolicited_report_interval(idev));
2718 	}
2719 	mutex_unlock(&idev->mc_lock);
2720 	in6_dev_put(idev);
2721 }
2722 
2723 static void mld_ifc_event(struct inet6_dev *idev)
2724 {
2725 	mc_assert_locked(idev);
2726 
2727 	if (mld_in_v1_mode(idev))
2728 		return;
2729 
2730 	idev->mc_ifc_count = idev->mc_qrv;
2731 	mld_ifc_start_work(idev, 1);
2732 }
2733 
2734 static void mld_mca_work(struct work_struct *work)
2735 {
2736 	struct ifmcaddr6 *ma = container_of(to_delayed_work(work),
2737 					    struct ifmcaddr6, mca_work);
2738 
2739 	mutex_lock(&ma->idev->mc_lock);
2740 	if (mld_in_v1_mode(ma->idev))
2741 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2742 	else
2743 		mld_send_report(ma->idev, ma);
2744 	WRITE_ONCE(ma->mca_flags, (ma->mca_flags | MAF_LAST_REPORTER) &
2745 		   ~MAF_TIMER_RUNNING);
2746 	mutex_unlock(&ma->idev->mc_lock);
2747 
2748 	ma_put(ma);
2749 }
2750 
2751 /* Device changing type */
2752 
2753 void ipv6_mc_unmap(struct inet6_dev *idev)
2754 {
2755 	struct ifmcaddr6 *i;
2756 
2757 	/* Install multicast list, except for all-nodes (already installed) */
2758 
2759 	mutex_lock(&idev->mc_lock);
2760 	for_each_mc_mclock(idev, i)
2761 		igmp6_group_dropped(i);
2762 	mutex_unlock(&idev->mc_lock);
2763 }
2764 
2765 void ipv6_mc_remap(struct inet6_dev *idev)
2766 {
2767 	ipv6_mc_up(idev);
2768 }
2769 
2770 /* Device going down */
2771 void ipv6_mc_down(struct inet6_dev *idev)
2772 {
2773 	struct ifmcaddr6 *i;
2774 
2775 	mutex_lock(&idev->mc_lock);
2776 	/* Withdraw multicast list */
2777 	for_each_mc_mclock(idev, i)
2778 		igmp6_group_dropped(i);
2779 	mutex_unlock(&idev->mc_lock);
2780 
2781 	/* Should stop work after group drop. or we will
2782 	 * start work again in mld_ifc_event()
2783 	 */
2784 	mld_query_stop_work(idev);
2785 	mld_report_stop_work(idev);
2786 
2787 	mutex_lock(&idev->mc_lock);
2788 	mld_ifc_stop_work(idev);
2789 	mld_gq_stop_work(idev);
2790 	mutex_unlock(&idev->mc_lock);
2791 
2792 	mld_dad_stop_work(idev);
2793 }
2794 
2795 static void ipv6_mc_reset(struct inet6_dev *idev)
2796 {
2797 	idev->mc_qrv = sysctl_mld_qrv;
2798 	idev->mc_qi = MLD_QI_DEFAULT;
2799 	idev->mc_qri = MLD_QRI_DEFAULT;
2800 	idev->mc_v1_seen = 0;
2801 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2802 }
2803 
2804 /* Device going up */
2805 
2806 void ipv6_mc_up(struct inet6_dev *idev)
2807 {
2808 	struct ifmcaddr6 *i;
2809 
2810 	/* Install multicast list, except for all-nodes (already installed) */
2811 
2812 	ipv6_mc_reset(idev);
2813 	mutex_lock(&idev->mc_lock);
2814 	for_each_mc_mclock(idev, i) {
2815 		mld_del_delrec(idev, i);
2816 		igmp6_group_added(i);
2817 	}
2818 	mutex_unlock(&idev->mc_lock);
2819 }
2820 
2821 /* IPv6 device initialization. */
2822 
2823 void ipv6_mc_init_dev(struct inet6_dev *idev)
2824 {
2825 	idev->mc_gq_running = 0;
2826 	INIT_DELAYED_WORK(&idev->mc_gq_work, mld_gq_work);
2827 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
2828 	idev->mc_ifc_count = 0;
2829 	INIT_DELAYED_WORK(&idev->mc_ifc_work, mld_ifc_work);
2830 	INIT_DELAYED_WORK(&idev->mc_dad_work, mld_dad_work);
2831 	INIT_DELAYED_WORK(&idev->mc_query_work, mld_query_work);
2832 	INIT_DELAYED_WORK(&idev->mc_report_work, mld_report_work);
2833 	skb_queue_head_init(&idev->mc_query_queue);
2834 	skb_queue_head_init(&idev->mc_report_queue);
2835 	spin_lock_init(&idev->mc_query_lock);
2836 	spin_lock_init(&idev->mc_report_lock);
2837 	mutex_init(&idev->mc_lock);
2838 	ipv6_mc_reset(idev);
2839 }
2840 
2841 /*
2842  *	Device is about to be destroyed: clean up.
2843  */
2844 
2845 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2846 {
2847 	struct ifmcaddr6 *i;
2848 
2849 	/* Deactivate works */
2850 	ipv6_mc_down(idev);
2851 	mutex_lock(&idev->mc_lock);
2852 	mld_clear_delrec(idev);
2853 	mutex_unlock(&idev->mc_lock);
2854 	mld_clear_query(idev);
2855 	mld_clear_report(idev);
2856 
2857 	/* Delete all-nodes address. */
2858 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2859 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2860 	 * fail.
2861 	 */
2862 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2863 
2864 	if (idev->cnf.forwarding)
2865 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2866 
2867 	mutex_lock(&idev->mc_lock);
2868 	while ((i = mc_dereference(idev->mc_list, idev))) {
2869 		rcu_assign_pointer(idev->mc_list, mc_dereference(i->next, idev));
2870 
2871 		ip6_mc_clear_src(i);
2872 		ma_put(i);
2873 	}
2874 	mutex_unlock(&idev->mc_lock);
2875 }
2876 
2877 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2878 {
2879 	struct ifmcaddr6 *pmc;
2880 
2881 	mutex_lock(&idev->mc_lock);
2882 	if (mld_in_v1_mode(idev)) {
2883 		for_each_mc_mclock(idev, pmc)
2884 			igmp6_join_group(pmc);
2885 	} else {
2886 		mld_send_report(idev, NULL);
2887 	}
2888 	mutex_unlock(&idev->mc_lock);
2889 }
2890 
2891 static int ipv6_mc_netdev_event(struct notifier_block *this,
2892 				unsigned long event,
2893 				void *ptr)
2894 {
2895 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2896 	struct inet6_dev *idev = __in6_dev_get(dev);
2897 
2898 	switch (event) {
2899 	case NETDEV_RESEND_IGMP:
2900 		if (idev)
2901 			ipv6_mc_rejoin_groups(idev);
2902 		break;
2903 	default:
2904 		break;
2905 	}
2906 
2907 	return NOTIFY_DONE;
2908 }
2909 
2910 static struct notifier_block igmp6_netdev_notifier = {
2911 	.notifier_call = ipv6_mc_netdev_event,
2912 };
2913 
2914 #ifdef CONFIG_PROC_FS
2915 struct igmp6_mc_iter_state {
2916 	struct seq_net_private p;
2917 	struct net_device *dev;
2918 	struct inet6_dev *idev;
2919 };
2920 
2921 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2922 
2923 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2924 {
2925 	struct ifmcaddr6 *im = NULL;
2926 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2927 	struct net *net = seq_file_net(seq);
2928 
2929 	state->idev = NULL;
2930 	for_each_netdev_rcu(net, state->dev) {
2931 		struct inet6_dev *idev;
2932 		idev = __in6_dev_get(state->dev);
2933 		if (!idev)
2934 			continue;
2935 
2936 		im = rcu_dereference(idev->mc_list);
2937 		if (im) {
2938 			state->idev = idev;
2939 			break;
2940 		}
2941 	}
2942 	return im;
2943 }
2944 
2945 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2946 {
2947 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2948 
2949 	im = rcu_dereference(im->next);
2950 	while (!im) {
2951 		state->dev = next_net_device_rcu(state->dev);
2952 		if (!state->dev) {
2953 			state->idev = NULL;
2954 			break;
2955 		}
2956 		state->idev = __in6_dev_get(state->dev);
2957 		if (!state->idev)
2958 			continue;
2959 		im = rcu_dereference(state->idev->mc_list);
2960 	}
2961 	return im;
2962 }
2963 
2964 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2965 {
2966 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2967 	if (im)
2968 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2969 			--pos;
2970 	return pos ? NULL : im;
2971 }
2972 
2973 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2974 	__acquires(RCU)
2975 {
2976 	rcu_read_lock();
2977 	return igmp6_mc_get_idx(seq, *pos);
2978 }
2979 
2980 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2981 {
2982 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2983 
2984 	++*pos;
2985 	return im;
2986 }
2987 
2988 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2989 	__releases(RCU)
2990 {
2991 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2992 
2993 	if (likely(state->idev))
2994 		state->idev = NULL;
2995 	state->dev = NULL;
2996 	rcu_read_unlock();
2997 }
2998 
2999 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
3000 {
3001 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
3002 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
3003 	unsigned int mca_flags = READ_ONCE(im->mca_flags);
3004 	unsigned long expires = READ_ONCE(im->mca_work.timer.expires);
3005 
3006 	seq_printf(seq,
3007 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
3008 		   state->dev->ifindex, state->dev->name,
3009 		   &im->mca_addr,
3010 		   READ_ONCE(im->mca_users), mca_flags,
3011 		   (mca_flags & MAF_TIMER_RUNNING) ?
3012 		   jiffies_to_clock_t(expires - jiffies) : 0);
3013 	return 0;
3014 }
3015 
3016 static const struct seq_operations igmp6_mc_seq_ops = {
3017 	.start	=	igmp6_mc_seq_start,
3018 	.next	=	igmp6_mc_seq_next,
3019 	.stop	=	igmp6_mc_seq_stop,
3020 	.show	=	igmp6_mc_seq_show,
3021 };
3022 
3023 struct igmp6_mcf_iter_state {
3024 	struct seq_net_private p;
3025 	struct net_device *dev;
3026 	struct inet6_dev *idev;
3027 	struct ifmcaddr6 *im;
3028 };
3029 
3030 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
3031 
3032 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
3033 {
3034 	struct ip6_sf_list *psf = NULL;
3035 	struct ifmcaddr6 *im = NULL;
3036 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3037 	struct net *net = seq_file_net(seq);
3038 
3039 	state->idev = NULL;
3040 	state->im = NULL;
3041 	for_each_netdev_rcu(net, state->dev) {
3042 		struct inet6_dev *idev;
3043 		idev = __in6_dev_get(state->dev);
3044 		if (unlikely(idev == NULL))
3045 			continue;
3046 
3047 		im = rcu_dereference(idev->mc_list);
3048 		if (likely(im)) {
3049 			psf = rcu_dereference(im->mca_sources);
3050 			if (likely(psf)) {
3051 				state->im = im;
3052 				state->idev = idev;
3053 				break;
3054 			}
3055 		}
3056 	}
3057 	return psf;
3058 }
3059 
3060 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
3061 {
3062 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3063 
3064 	psf = rcu_dereference(psf->sf_next);
3065 	while (!psf) {
3066 		state->im = rcu_dereference(state->im->next);
3067 		while (!state->im) {
3068 			state->dev = next_net_device_rcu(state->dev);
3069 			if (!state->dev) {
3070 				state->idev = NULL;
3071 				goto out;
3072 			}
3073 			state->idev = __in6_dev_get(state->dev);
3074 			if (!state->idev)
3075 				continue;
3076 			state->im = rcu_dereference(state->idev->mc_list);
3077 		}
3078 		psf = rcu_dereference(state->im->mca_sources);
3079 	}
3080 out:
3081 	return psf;
3082 }
3083 
3084 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
3085 {
3086 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
3087 	if (psf)
3088 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
3089 			--pos;
3090 	return pos ? NULL : psf;
3091 }
3092 
3093 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
3094 	__acquires(RCU)
3095 {
3096 	rcu_read_lock();
3097 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
3098 }
3099 
3100 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3101 {
3102 	struct ip6_sf_list *psf;
3103 	if (v == SEQ_START_TOKEN)
3104 		psf = igmp6_mcf_get_first(seq);
3105 	else
3106 		psf = igmp6_mcf_get_next(seq, v);
3107 	++*pos;
3108 	return psf;
3109 }
3110 
3111 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
3112 	__releases(RCU)
3113 {
3114 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3115 
3116 	if (likely(state->im))
3117 		state->im = NULL;
3118 	if (likely(state->idev))
3119 		state->idev = NULL;
3120 
3121 	state->dev = NULL;
3122 	rcu_read_unlock();
3123 }
3124 
3125 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
3126 {
3127 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
3128 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3129 
3130 	if (v == SEQ_START_TOKEN) {
3131 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
3132 	} else {
3133 		seq_printf(seq,
3134 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
3135 			   state->dev->ifindex, state->dev->name,
3136 			   &state->im->mca_addr,
3137 			   &psf->sf_addr,
3138 			   READ_ONCE(psf->sf_count[MCAST_INCLUDE]),
3139 			   READ_ONCE(psf->sf_count[MCAST_EXCLUDE]));
3140 	}
3141 	return 0;
3142 }
3143 
3144 static const struct seq_operations igmp6_mcf_seq_ops = {
3145 	.start	=	igmp6_mcf_seq_start,
3146 	.next	=	igmp6_mcf_seq_next,
3147 	.stop	=	igmp6_mcf_seq_stop,
3148 	.show	=	igmp6_mcf_seq_show,
3149 };
3150 
3151 static int __net_init igmp6_proc_init(struct net *net)
3152 {
3153 	int err;
3154 
3155 	err = -ENOMEM;
3156 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
3157 			sizeof(struct igmp6_mc_iter_state)))
3158 		goto out;
3159 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
3160 			&igmp6_mcf_seq_ops,
3161 			sizeof(struct igmp6_mcf_iter_state)))
3162 		goto out_proc_net_igmp6;
3163 
3164 	err = 0;
3165 out:
3166 	return err;
3167 
3168 out_proc_net_igmp6:
3169 	remove_proc_entry("igmp6", net->proc_net);
3170 	goto out;
3171 }
3172 
3173 static void __net_exit igmp6_proc_exit(struct net *net)
3174 {
3175 	remove_proc_entry("mcfilter6", net->proc_net);
3176 	remove_proc_entry("igmp6", net->proc_net);
3177 }
3178 #else
3179 static inline int igmp6_proc_init(struct net *net)
3180 {
3181 	return 0;
3182 }
3183 static inline void igmp6_proc_exit(struct net *net)
3184 {
3185 }
3186 #endif
3187 
3188 static int __net_init igmp6_net_init(struct net *net)
3189 {
3190 	int err;
3191 
3192 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
3193 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3194 	if (err < 0) {
3195 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
3196 		       err);
3197 		goto out;
3198 	}
3199 
3200 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
3201 	net->ipv6.igmp_sk->sk_allocation = GFP_KERNEL;
3202 
3203 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
3204 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3205 	if (err < 0) {
3206 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
3207 		       err);
3208 		goto out_sock_create;
3209 	}
3210 
3211 	err = igmp6_proc_init(net);
3212 	if (err)
3213 		goto out_sock_create_autojoin;
3214 
3215 	return 0;
3216 
3217 out_sock_create_autojoin:
3218 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3219 out_sock_create:
3220 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3221 out:
3222 	return err;
3223 }
3224 
3225 static void __net_exit igmp6_net_exit(struct net *net)
3226 {
3227 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3228 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3229 	igmp6_proc_exit(net);
3230 }
3231 
3232 static struct pernet_operations igmp6_net_ops = {
3233 	.init = igmp6_net_init,
3234 	.exit = igmp6_net_exit,
3235 };
3236 
3237 int __init igmp6_init(void)
3238 {
3239 	int err;
3240 
3241 	err = register_pernet_subsys(&igmp6_net_ops);
3242 	if (err)
3243 		return err;
3244 
3245 	mld_wq = create_workqueue("mld");
3246 	if (!mld_wq) {
3247 		unregister_pernet_subsys(&igmp6_net_ops);
3248 		return -ENOMEM;
3249 	}
3250 
3251 	return err;
3252 }
3253 
3254 int __init igmp6_late_init(void)
3255 {
3256 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3257 }
3258 
3259 void igmp6_cleanup(void)
3260 {
3261 	unregister_pernet_subsys(&igmp6_net_ops);
3262 	destroy_workqueue(mld_wq);
3263 }
3264 
3265 void igmp6_late_cleanup(void)
3266 {
3267 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3268 }
3269