xref: /linux/net/ipv6/mcast.c (revision 59e6295fac26b8e85c1ea859cdd89fa1e47519d7)
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(struct ifa_cacheinfo)),
912 			GFP_KERNEL);
913 	if (!skb)
914 		goto error;
915 
916 	err = inet6_fill_ifmcaddr(skb, ifmca, &fillargs);
917 	if (err < 0) {
918 		WARN_ON_ONCE(err == -EMSGSIZE);
919 		nlmsg_free(skb);
920 		goto error;
921 	}
922 
923 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MCADDR, NULL, GFP_KERNEL);
924 	return;
925 error:
926 	rtnl_set_sk_err(net, RTNLGRP_IPV6_MCADDR, err);
927 }
928 
929 /*
930  *	device multicast group inc (add if not found)
931  */
932 static int __ipv6_dev_mc_inc(struct net_device *dev,
933 			     const struct in6_addr *addr, unsigned int mode)
934 {
935 	struct inet6_dev *idev;
936 	struct ifmcaddr6 *mc;
937 
938 	/* we need to take a reference on idev */
939 	idev = in6_dev_get(dev);
940 	if (!idev)
941 		return -EINVAL;
942 
943 	mutex_lock(&idev->mc_lock);
944 
945 	if (READ_ONCE(idev->dead)) {
946 		mutex_unlock(&idev->mc_lock);
947 		in6_dev_put(idev);
948 		return -ENODEV;
949 	}
950 
951 	for_each_mc_mclock(idev, mc) {
952 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
953 			WRITE_ONCE(mc->mca_users, mc->mca_users + 1);
954 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
955 			mutex_unlock(&idev->mc_lock);
956 			in6_dev_put(idev);
957 			return 0;
958 		}
959 	}
960 
961 	mc = mca_alloc(idev, addr, mode);
962 	if (!mc) {
963 		mutex_unlock(&idev->mc_lock);
964 		in6_dev_put(idev);
965 		return -ENOMEM;
966 	}
967 
968 	rcu_assign_pointer(mc->next, idev->mc_list);
969 	rcu_assign_pointer(idev->mc_list, mc);
970 
971 	mld_del_delrec(idev, mc);
972 	igmp6_group_added(mc);
973 	inet6_ifmcaddr_notify(dev, mc, RTM_NEWMULTICAST);
974 	mutex_unlock(&idev->mc_lock);
975 
976 	return 0;
977 }
978 
979 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
980 {
981 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
982 }
983 EXPORT_SYMBOL(ipv6_dev_mc_inc);
984 
985 /*
986  * device multicast group del
987  */
988 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
989 {
990 	struct ifmcaddr6 *ma, __rcu **map;
991 
992 	mutex_lock(&idev->mc_lock);
993 
994 	for (map = &idev->mc_list;
995 	     (ma = mc_dereference(*map, idev));
996 	     map = &ma->next) {
997 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
998 			int new_users = ma->mca_users - 1;
999 
1000 			WRITE_ONCE(ma->mca_users, new_users);
1001 			if (new_users == 0) {
1002 				*map = ma->next;
1003 
1004 				igmp6_group_dropped(ma);
1005 				inet6_ifmcaddr_notify(idev->dev, ma,
1006 						      RTM_DELMULTICAST);
1007 				ip6_mc_clear_src(ma);
1008 				mutex_unlock(&idev->mc_lock);
1009 
1010 				ma_put(ma);
1011 				return 0;
1012 			}
1013 			mutex_unlock(&idev->mc_lock);
1014 			return 0;
1015 		}
1016 	}
1017 
1018 	mutex_unlock(&idev->mc_lock);
1019 	return -ENOENT;
1020 }
1021 
1022 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
1023 {
1024 	struct inet6_dev *idev;
1025 	int err;
1026 
1027 	idev = in6_dev_get(dev);
1028 	if (!idev)
1029 		return -ENODEV;
1030 
1031 	err = __ipv6_dev_mc_dec(idev, addr);
1032 	in6_dev_put(idev);
1033 
1034 	return err;
1035 }
1036 EXPORT_SYMBOL(ipv6_dev_mc_dec);
1037 
1038 /*
1039  *	check if the interface/address pair is valid
1040  */
1041 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
1042 			 const struct in6_addr *src_addr)
1043 {
1044 	struct inet6_dev *idev;
1045 	struct ifmcaddr6 *mc;
1046 	bool rv = false;
1047 
1048 	rcu_read_lock();
1049 	idev = __in6_dev_get(dev);
1050 	if (!idev)
1051 		goto unlock;
1052 	for_each_mc_rcu(idev, mc) {
1053 		if (ipv6_addr_equal(&mc->mca_addr, group))
1054 			break;
1055 	}
1056 	if (!mc)
1057 		goto unlock;
1058 	if (src_addr && !ipv6_addr_any(src_addr)) {
1059 		struct ip6_sf_list *psf;
1060 
1061 		for_each_psf_rcu(mc, psf) {
1062 			if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1063 				break;
1064 		}
1065 		if (psf)
1066 			rv = READ_ONCE(psf->sf_count[MCAST_INCLUDE]) ||
1067 				READ_ONCE(psf->sf_count[MCAST_EXCLUDE]) !=
1068 				READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]);
1069 		else
1070 			rv = READ_ONCE(mc->mca_sfcount[MCAST_EXCLUDE]) != 0;
1071 	} else {
1072 		rv = true; /* don't filter unspecified source */
1073 	}
1074 unlock:
1075 	rcu_read_unlock();
1076 	return rv;
1077 }
1078 
1079 static void mld_gq_start_work(struct inet6_dev *idev)
1080 {
1081 	unsigned long tv = get_random_u32_below(idev->mc_maxdelay);
1082 
1083 	mc_assert_locked(idev);
1084 
1085 	idev->mc_gq_running = 1;
1086 	if (in6_dev_hold_safe(idev)) {
1087 		if (mod_delayed_work(mld_wq, &idev->mc_gq_work, tv + 2))
1088 			in6_dev_put(idev);
1089 	}
1090 }
1091 
1092 static void mld_gq_stop_work(struct inet6_dev *idev)
1093 {
1094 	mc_assert_locked(idev);
1095 
1096 	idev->mc_gq_running = 0;
1097 	if (cancel_delayed_work(&idev->mc_gq_work))
1098 		__in6_dev_put(idev);
1099 }
1100 
1101 static void mld_ifc_start_work(struct inet6_dev *idev, unsigned long delay)
1102 {
1103 	unsigned long tv = get_random_u32_below(delay);
1104 
1105 	mc_assert_locked(idev);
1106 
1107 	if (in6_dev_hold_safe(idev)) {
1108 		if (mod_delayed_work(mld_wq, &idev->mc_ifc_work, tv + 2))
1109 			in6_dev_put(idev);
1110 	}
1111 }
1112 
1113 static void mld_ifc_stop_work(struct inet6_dev *idev)
1114 {
1115 	mc_assert_locked(idev);
1116 
1117 	idev->mc_ifc_count = 0;
1118 	if (cancel_delayed_work(&idev->mc_ifc_work))
1119 		__in6_dev_put(idev);
1120 }
1121 
1122 static void mld_dad_start_work(struct inet6_dev *idev, unsigned long delay)
1123 {
1124 	unsigned long tv = get_random_u32_below(delay);
1125 
1126 	mc_assert_locked(idev);
1127 
1128 	if (in6_dev_hold_safe(idev)) {
1129 		if (mod_delayed_work(mld_wq, &idev->mc_dad_work, tv + 2))
1130 			in6_dev_put(idev);
1131 	}
1132 }
1133 
1134 static void mld_dad_stop_work(struct inet6_dev *idev)
1135 {
1136 	if (cancel_delayed_work(&idev->mc_dad_work))
1137 		__in6_dev_put(idev);
1138 }
1139 
1140 static void mld_query_stop_work(struct inet6_dev *idev)
1141 {
1142 	spin_lock_bh(&idev->mc_query_lock);
1143 	if (cancel_delayed_work(&idev->mc_query_work))
1144 		__in6_dev_put(idev);
1145 	spin_unlock_bh(&idev->mc_query_lock);
1146 }
1147 
1148 static void mld_report_stop_work(struct inet6_dev *idev)
1149 {
1150 	if (cancel_delayed_work_sync(&idev->mc_report_work))
1151 		__in6_dev_put(idev);
1152 }
1153 
1154 /* IGMP handling (alias multicast ICMPv6 messages) */
1155 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1156 {
1157 	unsigned long delay = resptime;
1158 
1159 	mc_assert_locked(ma->idev);
1160 
1161 	/* Do not start work for these addresses */
1162 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1163 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1164 		return;
1165 
1166 	if (cancel_delayed_work(&ma->mca_work)) {
1167 		refcount_dec(&ma->mca_refcnt);
1168 		delay = ma->mca_work.timer.expires - jiffies;
1169 	}
1170 
1171 	if (delay >= resptime)
1172 		delay = get_random_u32_below(resptime);
1173 
1174 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
1175 		refcount_inc(&ma->mca_refcnt);
1176 	WRITE_ONCE(ma->mca_flags, ma->mca_flags | MAF_TIMER_RUNNING);
1177 }
1178 
1179 /* mark EXCLUDE-mode sources */
1180 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1181 			     const struct in6_addr *srcs)
1182 {
1183 	struct ip6_sf_list *psf;
1184 	int i, scount;
1185 
1186 	mc_assert_locked(pmc->idev);
1187 
1188 	scount = 0;
1189 	for_each_psf_mclock(pmc, psf) {
1190 		if (scount == nsrcs)
1191 			break;
1192 		for (i = 0; i < nsrcs; i++) {
1193 			/* skip inactive filters */
1194 			if (psf->sf_count[MCAST_INCLUDE] ||
1195 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1196 			    psf->sf_count[MCAST_EXCLUDE])
1197 				break;
1198 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1199 				scount++;
1200 				break;
1201 			}
1202 		}
1203 	}
1204 	WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
1205 	if (scount == nsrcs)	/* all sources excluded */
1206 		return false;
1207 	return true;
1208 }
1209 
1210 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1211 			    const struct in6_addr *srcs)
1212 {
1213 	struct ip6_sf_list *psf;
1214 	int i, scount;
1215 
1216 	mc_assert_locked(pmc->idev);
1217 
1218 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1219 		return mld_xmarksources(pmc, nsrcs, srcs);
1220 
1221 	/* mark INCLUDE-mode sources */
1222 
1223 	scount = 0;
1224 	for_each_psf_mclock(pmc, psf) {
1225 		if (scount == nsrcs)
1226 			break;
1227 		for (i = 0; i < nsrcs; i++) {
1228 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1229 				psf->sf_gsresp = 1;
1230 				scount++;
1231 				break;
1232 			}
1233 		}
1234 	}
1235 	if (!scount) {
1236 		WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
1237 		return false;
1238 	}
1239 	WRITE_ONCE(pmc->mca_flags, pmc->mca_flags | MAF_GSQUERY);
1240 	return true;
1241 }
1242 
1243 static int mld_force_mld_version(const struct inet6_dev *idev)
1244 {
1245 	const struct net *net = dev_net(idev->dev);
1246 	int all_force;
1247 
1248 	all_force = READ_ONCE(net->ipv6.devconf_all->force_mld_version);
1249 	/* Normally, both are 0 here. If enforcement to a particular is
1250 	 * being used, individual device enforcement will have a lower
1251 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1252 	 */
1253 	return all_force ?: READ_ONCE(idev->cnf.force_mld_version);
1254 }
1255 
1256 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1257 {
1258 	return mld_force_mld_version(idev) == 2;
1259 }
1260 
1261 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1262 {
1263 	return mld_force_mld_version(idev) == 1;
1264 }
1265 
1266 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1267 {
1268 	if (mld_in_v2_mode_only(idev))
1269 		return false;
1270 	if (mld_in_v1_mode_only(idev))
1271 		return true;
1272 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1273 		return true;
1274 
1275 	return false;
1276 }
1277 
1278 static void mld_set_v1_mode(struct inet6_dev *idev)
1279 {
1280 	/* RFC3810, relevant sections:
1281 	 *  - 9.1. Robustness Variable
1282 	 *  - 9.2. Query Interval
1283 	 *  - 9.3. Query Response Interval
1284 	 *  - 9.12. Older Version Querier Present Timeout
1285 	 */
1286 	unsigned long switchback;
1287 
1288 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1289 
1290 	idev->mc_v1_seen = jiffies + switchback;
1291 }
1292 
1293 static void mld_update_qrv(struct inet6_dev *idev,
1294 			   const struct mld2_query *mlh2)
1295 {
1296 	/* RFC3810, relevant sections:
1297 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1298 	 *  - 9.1. Robustness Variable
1299 	 */
1300 
1301 	/* The value of the Robustness Variable MUST NOT be zero,
1302 	 * and SHOULD NOT be one. Catch this here if we ever run
1303 	 * into such a case in future.
1304 	 */
1305 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1306 	WARN_ON(idev->mc_qrv == 0);
1307 
1308 	if (mlh2->mld2q_qrv > 0)
1309 		idev->mc_qrv = mlh2->mld2q_qrv;
1310 
1311 	if (unlikely(idev->mc_qrv < min_qrv)) {
1312 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1313 				     idev->mc_qrv, min_qrv);
1314 		idev->mc_qrv = min_qrv;
1315 	}
1316 }
1317 
1318 static void mld_update_qi(struct inet6_dev *idev,
1319 			  const struct mld2_query *mlh2)
1320 {
1321 	/* RFC3810, relevant sections:
1322 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1323 	 *  - 9.2. Query Interval
1324 	 *  - 9.12. Older Version Querier Present Timeout
1325 	 *    (the [Query Interval] in the last Query received)
1326 	 */
1327 	idev->mc_qi = mldv2_qqi(mlh2) * HZ;
1328 }
1329 
1330 static void mld_update_qri(struct inet6_dev *idev,
1331 			   const struct mld2_query *mlh2)
1332 {
1333 	/* RFC3810, relevant sections:
1334 	 *  - 5.1.3. Maximum Response Code
1335 	 *  - 9.3. Query Response Interval
1336 	 */
1337 	idev->mc_qri = msecs_to_jiffies(mldv2_mrd(mlh2));
1338 }
1339 
1340 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1341 			  unsigned long *max_delay, bool v1_query)
1342 {
1343 	unsigned long mldv1_md;
1344 
1345 	/* Ignore v1 queries */
1346 	if (mld_in_v2_mode_only(idev))
1347 		return -EINVAL;
1348 
1349 	mldv1_md = ntohs(mld->mld_maxdelay);
1350 
1351 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1352 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1353 	 * only works when the exponential algorithm is not being
1354 	 * used (as MLDv1 is unaware of such things).
1355 	 *
1356 	 * According to the RFC author, the MLDv2 implementations
1357 	 * he's aware of all use a MRC < 32768 on start up queries.
1358 	 *
1359 	 * Thus, should we *ever* encounter something else larger
1360 	 * than that, just assume the maximum possible within our
1361 	 * reach.
1362 	 */
1363 	if (!v1_query)
1364 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1365 
1366 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1367 
1368 	/* MLDv1 router present: we need to go into v1 mode *only*
1369 	 * when an MLDv1 query is received as per section 9.12. of
1370 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1371 	 * queries MUST be of exactly 24 octets.
1372 	 */
1373 	if (v1_query)
1374 		mld_set_v1_mode(idev);
1375 
1376 	/* cancel MLDv2 report work */
1377 	mld_gq_stop_work(idev);
1378 	/* cancel the interface change work */
1379 	mld_ifc_stop_work(idev);
1380 	/* clear deleted report items */
1381 	mld_clear_delrec(idev);
1382 
1383 	return 0;
1384 }
1385 
1386 static void mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1387 			   unsigned long *max_delay)
1388 {
1389 	*max_delay = max(msecs_to_jiffies(mldv2_mrd(mld)), 1UL);
1390 
1391 	mld_update_qrv(idev, mld);
1392 	mld_update_qi(idev, mld);
1393 	mld_update_qri(idev, mld);
1394 
1395 	idev->mc_maxdelay = *max_delay;
1396 
1397 	return;
1398 }
1399 
1400 /* called with rcu_read_lock() */
1401 void igmp6_event_query(struct sk_buff *skb)
1402 {
1403 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1404 	bool put = false;
1405 
1406 	if (!idev || idev->dead)
1407 		goto out;
1408 
1409 	spin_lock_bh(&idev->mc_query_lock);
1410 	if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS &&
1411 	    in6_dev_hold_safe(idev)) {
1412 		__skb_queue_tail(&idev->mc_query_queue, skb);
1413 		if (mod_delayed_work(mld_wq, &idev->mc_query_work, 0))
1414 			put = true;
1415 		skb = NULL;
1416 	}
1417 	spin_unlock_bh(&idev->mc_query_lock);
1418 
1419 	if (put)
1420 		in6_dev_put(idev);
1421 out:
1422 	kfree_skb(skb);
1423 }
1424 
1425 static void __mld_query_work(struct sk_buff *skb)
1426 {
1427 	struct mld2_query *mlh2 = NULL;
1428 	unsigned long max_delay;
1429 	struct inet6_dev *idev;
1430 	struct in6_addr group;
1431 	struct ifmcaddr6 *ma;
1432 	struct mld_msg *mld;
1433 	int group_type;
1434 	int mark = 0;
1435 	int len, err;
1436 
1437 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1438 		goto kfree_skb;
1439 
1440 	/* compute payload length excluding extension headers */
1441 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1442 	len -= skb_network_header_len(skb);
1443 
1444 	/* RFC3810 6.2
1445 	 * Upon reception of an MLD message that contains a Query, the node
1446 	 * checks if the source address of the message is a valid link-local
1447 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1448 	 * option is present in the Hop-By-Hop Options header of the IPv6
1449 	 * packet.  If any of these checks fails, the packet is dropped.
1450 	 */
1451 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1452 	    ipv6_hdr(skb)->hop_limit != 1 ||
1453 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1454 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1455 		goto kfree_skb;
1456 
1457 	idev = in6_dev_get(skb->dev);
1458 	if (!idev)
1459 		goto kfree_skb;
1460 
1461 	mld = (struct mld_msg *)icmp6_hdr(skb);
1462 	group = mld->mld_mca;
1463 	group_type = ipv6_addr_type(&group);
1464 
1465 	if (group_type != IPV6_ADDR_ANY &&
1466 	    !(group_type&IPV6_ADDR_MULTICAST))
1467 		goto out;
1468 
1469 	if (len < MLD_V1_QUERY_LEN) {
1470 		goto out;
1471 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1472 		err = mld_process_v1(idev, mld, &max_delay,
1473 				     len == MLD_V1_QUERY_LEN);
1474 		if (err < 0)
1475 			goto out;
1476 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1477 		int srcs_offset = sizeof(struct mld2_query) -
1478 				  sizeof(struct icmp6hdr);
1479 
1480 		if (!pskb_may_pull(skb, srcs_offset))
1481 			goto out;
1482 
1483 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1484 
1485 		mld_process_v2(idev, mlh2, &max_delay);
1486 
1487 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1488 			if (mlh2->mld2q_nsrcs)
1489 				goto out; /* no sources allowed */
1490 
1491 			mld_gq_start_work(idev);
1492 			goto out;
1493 		}
1494 		/* mark sources to include, if group & source-specific */
1495 		if (mlh2->mld2q_nsrcs != 0) {
1496 			if (!pskb_may_pull(skb, srcs_offset +
1497 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1498 				goto out;
1499 
1500 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1501 			mark = 1;
1502 		}
1503 	} else {
1504 		goto out;
1505 	}
1506 
1507 	if (group_type == IPV6_ADDR_ANY) {
1508 		for_each_mc_mclock(idev, ma) {
1509 			igmp6_group_queried(ma, max_delay);
1510 		}
1511 	} else {
1512 		for_each_mc_mclock(idev, ma) {
1513 			unsigned int flags;
1514 
1515 			if (!ipv6_addr_equal(&group, &ma->mca_addr))
1516 				continue;
1517 			flags = ma->mca_flags;
1518 
1519 			if (flags & MAF_TIMER_RUNNING) {
1520 				/* gsquery <- gsquery && mark */
1521 				if (!mark)
1522 					WRITE_ONCE(ma->mca_flags,
1523 						   flags & ~MAF_GSQUERY);
1524 			} else {
1525 				/* gsquery <- mark */
1526 				if (mark)
1527 					WRITE_ONCE(ma->mca_flags,
1528 						   flags | MAF_GSQUERY);
1529 				else
1530 					WRITE_ONCE(ma->mca_flags,
1531 						   flags & ~MAF_GSQUERY);
1532 			}
1533 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1534 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1535 				igmp6_group_queried(ma, max_delay);
1536 			break;
1537 		}
1538 	}
1539 
1540 out:
1541 	in6_dev_put(idev);
1542 kfree_skb:
1543 	consume_skb(skb);
1544 }
1545 
1546 static void mld_query_work(struct work_struct *work)
1547 {
1548 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1549 					      struct inet6_dev,
1550 					      mc_query_work);
1551 	struct sk_buff_head q;
1552 	struct sk_buff *skb;
1553 	bool rework = false;
1554 	int cnt = 0;
1555 
1556 	skb_queue_head_init(&q);
1557 
1558 	spin_lock_bh(&idev->mc_query_lock);
1559 	while ((skb = __skb_dequeue(&idev->mc_query_queue))) {
1560 		__skb_queue_tail(&q, skb);
1561 
1562 		if (++cnt >= MLD_MAX_QUEUE) {
1563 			rework = true;
1564 			break;
1565 		}
1566 	}
1567 	spin_unlock_bh(&idev->mc_query_lock);
1568 
1569 	mutex_lock(&idev->mc_lock);
1570 	while ((skb = __skb_dequeue(&q)))
1571 		__mld_query_work(skb);
1572 	mutex_unlock(&idev->mc_lock);
1573 
1574 	if (rework && queue_delayed_work(mld_wq, &idev->mc_query_work, 0))
1575 		return;
1576 
1577 	in6_dev_put(idev);
1578 }
1579 
1580 /* called with rcu_read_lock() */
1581 void igmp6_event_report(struct sk_buff *skb)
1582 {
1583 	struct inet6_dev *idev = __in6_dev_get(skb->dev);
1584 	bool put = false;
1585 
1586 	if (!idev || idev->dead)
1587 		goto out;
1588 
1589 	spin_lock_bh(&idev->mc_report_lock);
1590 	if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS &&
1591 	    in6_dev_hold_safe(idev)) {
1592 		__skb_queue_tail(&idev->mc_report_queue, skb);
1593 		if (mod_delayed_work(mld_wq, &idev->mc_report_work, 0))
1594 			put = true;
1595 		skb = NULL;
1596 	}
1597 	spin_unlock_bh(&idev->mc_report_lock);
1598 
1599 	if (put)
1600 		in6_dev_put(idev);
1601 out:
1602 	kfree_skb(skb);
1603 }
1604 
1605 static void __mld_report_work(struct sk_buff *skb)
1606 {
1607 	struct inet6_dev *idev;
1608 	struct ifmcaddr6 *ma;
1609 	struct mld_msg *mld;
1610 	int addr_type;
1611 
1612 	/* Our own report looped back. Ignore it. */
1613 	if (skb->pkt_type == PACKET_LOOPBACK)
1614 		goto kfree_skb;
1615 
1616 	/* send our report if the MC router may not have heard this report */
1617 	if (skb->pkt_type != PACKET_MULTICAST &&
1618 	    skb->pkt_type != PACKET_BROADCAST)
1619 		goto kfree_skb;
1620 
1621 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1622 		goto kfree_skb;
1623 
1624 	mld = (struct mld_msg *)icmp6_hdr(skb);
1625 
1626 	/* Drop reports with not link local source */
1627 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1628 	if (addr_type != IPV6_ADDR_ANY &&
1629 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1630 		goto kfree_skb;
1631 
1632 	idev = in6_dev_get(skb->dev);
1633 	if (!idev)
1634 		goto kfree_skb;
1635 
1636 	/*
1637 	 *	Cancel the work for this group
1638 	 */
1639 
1640 	for_each_mc_mclock(idev, ma) {
1641 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1642 			if (cancel_delayed_work(&ma->mca_work))
1643 				refcount_dec(&ma->mca_refcnt);
1644 			WRITE_ONCE(ma->mca_flags,
1645 				   ma->mca_flags & ~(MAF_LAST_REPORTER |
1646 						     MAF_TIMER_RUNNING));
1647 			break;
1648 		}
1649 	}
1650 
1651 	in6_dev_put(idev);
1652 kfree_skb:
1653 	consume_skb(skb);
1654 }
1655 
1656 static void mld_report_work(struct work_struct *work)
1657 {
1658 	struct inet6_dev *idev = container_of(to_delayed_work(work),
1659 					      struct inet6_dev,
1660 					      mc_report_work);
1661 	struct sk_buff_head q;
1662 	struct sk_buff *skb;
1663 	bool rework = false;
1664 	int cnt = 0;
1665 
1666 	skb_queue_head_init(&q);
1667 	spin_lock_bh(&idev->mc_report_lock);
1668 	while ((skb = __skb_dequeue(&idev->mc_report_queue))) {
1669 		__skb_queue_tail(&q, skb);
1670 
1671 		if (++cnt >= MLD_MAX_QUEUE) {
1672 			rework = true;
1673 			break;
1674 		}
1675 	}
1676 	spin_unlock_bh(&idev->mc_report_lock);
1677 
1678 	mutex_lock(&idev->mc_lock);
1679 	while ((skb = __skb_dequeue(&q)))
1680 		__mld_report_work(skb);
1681 	mutex_unlock(&idev->mc_lock);
1682 
1683 	if (rework && queue_delayed_work(mld_wq, &idev->mc_report_work, 0))
1684 		return;
1685 
1686 	in6_dev_put(idev);
1687 }
1688 
1689 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1690 		  int gdeleted, int sdeleted)
1691 {
1692 	switch (type) {
1693 	case MLD2_MODE_IS_INCLUDE:
1694 	case MLD2_MODE_IS_EXCLUDE:
1695 		if (gdeleted || sdeleted)
1696 			return false;
1697 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1698 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1699 				return true;
1700 			/* don't include if this source is excluded
1701 			 * in all filters
1702 			 */
1703 			if (psf->sf_count[MCAST_INCLUDE])
1704 				return type == MLD2_MODE_IS_INCLUDE;
1705 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1706 				psf->sf_count[MCAST_EXCLUDE];
1707 		}
1708 		return false;
1709 	case MLD2_CHANGE_TO_INCLUDE:
1710 		if (gdeleted || sdeleted)
1711 			return false;
1712 		return psf->sf_count[MCAST_INCLUDE] != 0;
1713 	case MLD2_CHANGE_TO_EXCLUDE:
1714 		if (gdeleted || sdeleted)
1715 			return false;
1716 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1717 		    psf->sf_count[MCAST_INCLUDE])
1718 			return false;
1719 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1720 			psf->sf_count[MCAST_EXCLUDE];
1721 	case MLD2_ALLOW_NEW_SOURCES:
1722 		if (gdeleted || !psf->sf_crcount)
1723 			return false;
1724 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1725 	case MLD2_BLOCK_OLD_SOURCES:
1726 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1727 			return gdeleted || (psf->sf_crcount && sdeleted);
1728 		return psf->sf_crcount && !gdeleted && !sdeleted;
1729 	}
1730 	return false;
1731 }
1732 
1733 static int
1734 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1735 {
1736 	struct ip6_sf_list *psf;
1737 	int scount = 0;
1738 
1739 	for_each_psf_mclock(pmc, psf) {
1740 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1741 			continue;
1742 		scount++;
1743 	}
1744 	return scount;
1745 }
1746 
1747 static void ip6_mc_hdr(const struct sock *sk, struct sk_buff *skb,
1748 		       struct net_device *dev, const struct in6_addr *saddr,
1749 		       const struct in6_addr *daddr, int proto, int len)
1750 {
1751 	struct ipv6hdr *hdr;
1752 
1753 	skb->protocol = htons(ETH_P_IPV6);
1754 	skb->dev = dev;
1755 
1756 	skb_reset_network_header(skb);
1757 	skb_put(skb, sizeof(struct ipv6hdr));
1758 	hdr = ipv6_hdr(skb);
1759 
1760 	ip6_flow_hdr(hdr, 0, 0);
1761 
1762 	hdr->payload_len = htons(len);
1763 	hdr->nexthdr = proto;
1764 	hdr->hop_limit = READ_ONCE(inet6_sk(sk)->hop_limit);
1765 
1766 	hdr->saddr = *saddr;
1767 	hdr->daddr = *daddr;
1768 }
1769 
1770 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1771 {
1772 	u8 ra[8] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT,
1773 		     2, 0, 0, IPV6_TLV_PADN, 0 };
1774 	struct net_device *dev = idev->dev;
1775 	int hlen = LL_RESERVED_SPACE(dev);
1776 	int tlen = dev->needed_tailroom;
1777 	const struct in6_addr *saddr;
1778 	struct in6_addr addr_buf;
1779 	struct mld2_report *pmr;
1780 	struct sk_buff *skb;
1781 	unsigned int size;
1782 	struct sock *sk;
1783 	struct net *net;
1784 
1785 	/* we assume size > sizeof(ra) here
1786 	 * Also try to not allocate high-order pages for big MTU
1787 	 */
1788 	size = min_t(int, mtu, PAGE_SIZE / 2) + hlen + tlen;
1789 	skb = alloc_skb(size, GFP_KERNEL);
1790 	if (!skb)
1791 		return NULL;
1792 
1793 	skb->priority = TC_PRIO_CONTROL;
1794 	skb_reserve(skb, hlen);
1795 	skb_tailroom_reserve(skb, mtu, tlen);
1796 
1797 	rcu_read_lock();
1798 
1799 	net = dev_net_rcu(dev);
1800 	sk = net->ipv6.igmp_sk;
1801 	skb_set_owner_w(skb, sk);
1802 
1803 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1804 		/* <draft-ietf-magma-mld-source-05.txt>:
1805 		 * use unspecified address as the source address
1806 		 * when a valid link-local address is not available.
1807 		 */
1808 		saddr = &in6addr_any;
1809 	} else
1810 		saddr = &addr_buf;
1811 
1812 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1813 
1814 	rcu_read_unlock();
1815 
1816 	skb_put_data(skb, ra, sizeof(ra));
1817 
1818 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1819 	skb_put(skb, sizeof(*pmr));
1820 	pmr = (struct mld2_report *)skb_transport_header(skb);
1821 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1822 	pmr->mld2r_resv1 = 0;
1823 	pmr->mld2r_cksum = 0;
1824 	pmr->mld2r_resv2 = 0;
1825 	pmr->mld2r_ngrec = 0;
1826 	return skb;
1827 }
1828 
1829 static void mld_sendpack(struct sk_buff *skb)
1830 {
1831 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1832 	struct mld2_report *pmr =
1833 			      (struct mld2_report *)skb_transport_header(skb);
1834 	int payload_len, mldlen;
1835 	struct inet6_dev *idev;
1836 	struct net *net = dev_net(skb->dev);
1837 	int err;
1838 	struct flowi6 fl6;
1839 	struct dst_entry *dst;
1840 
1841 	rcu_read_lock();
1842 	idev = __in6_dev_get(skb->dev);
1843 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
1844 
1845 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1846 		sizeof(*pip6);
1847 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1848 	pip6->payload_len = htons(payload_len);
1849 
1850 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1851 					   IPPROTO_ICMPV6,
1852 					   csum_partial(skb_transport_header(skb),
1853 							mldlen, 0));
1854 
1855 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1856 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1857 			 skb->dev->ifindex);
1858 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1859 
1860 	err = 0;
1861 	if (IS_ERR(dst)) {
1862 		err = PTR_ERR(dst);
1863 		dst = NULL;
1864 	}
1865 	skb_dst_set(skb, dst);
1866 	if (err)
1867 		goto err_out;
1868 
1869 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1870 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1871 		      dst_output);
1872 out:
1873 	if (!err) {
1874 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1875 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1876 	} else {
1877 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1878 	}
1879 
1880 	rcu_read_unlock();
1881 	return;
1882 
1883 err_out:
1884 	kfree_skb(skb);
1885 	goto out;
1886 }
1887 
1888 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1889 {
1890 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1891 }
1892 
1893 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1894 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1895 {
1896 	struct mld2_report *pmr;
1897 	struct mld2_grec *pgr;
1898 
1899 	if (!skb) {
1900 		skb = mld_newpack(pmc->idev, mtu);
1901 		if (!skb)
1902 			return NULL;
1903 	}
1904 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1905 	pgr->grec_type = type;
1906 	pgr->grec_auxwords = 0;
1907 	pgr->grec_nsrcs = 0;
1908 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1909 	pmr = (struct mld2_report *)skb_transport_header(skb);
1910 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1911 	*ppgr = pgr;
1912 	return skb;
1913 }
1914 
1915 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1916 
1917 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1918 				int type, int gdeleted, int sdeleted,
1919 				int crsend)
1920 {
1921 	struct ip6_sf_list *psf, *psf_prev, *psf_next;
1922 	int scount, stotal, first, isquery, truncate;
1923 	struct ip6_sf_list __rcu **psf_list;
1924 	struct inet6_dev *idev = pmc->idev;
1925 	struct net_device *dev = idev->dev;
1926 	struct mld2_grec *pgr = NULL;
1927 	struct mld2_report *pmr;
1928 	unsigned int mtu;
1929 
1930 	mc_assert_locked(idev);
1931 
1932 	if (pmc->mca_flags & MAF_NOREPORT)
1933 		return skb;
1934 
1935 	mtu = READ_ONCE(dev->mtu);
1936 	if (mtu < IPV6_MIN_MTU)
1937 		return skb;
1938 
1939 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1940 		  type == MLD2_MODE_IS_EXCLUDE;
1941 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1942 		    type == MLD2_CHANGE_TO_EXCLUDE;
1943 
1944 	stotal = scount = 0;
1945 
1946 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1947 
1948 	if (!rcu_access_pointer(*psf_list))
1949 		goto empty_source;
1950 
1951 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1952 
1953 	/* EX and TO_EX get a fresh packet, if needed */
1954 	if (truncate) {
1955 		if (pmr && pmr->mld2r_ngrec &&
1956 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1957 			if (skb)
1958 				mld_sendpack(skb);
1959 			skb = mld_newpack(idev, mtu);
1960 		}
1961 	}
1962 	first = 1;
1963 	psf_prev = NULL;
1964 	for (psf = mc_dereference(*psf_list, idev);
1965 	     psf;
1966 	     psf = psf_next) {
1967 		struct in6_addr *psrc;
1968 
1969 		psf_next = mc_dereference(psf->sf_next, idev);
1970 
1971 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1972 			psf_prev = psf;
1973 			continue;
1974 		}
1975 
1976 		/* Based on RFC3810 6.1. Should not send source-list change
1977 		 * records when there is a filter mode change.
1978 		 */
1979 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1980 		     (!gdeleted && pmc->mca_crcount)) &&
1981 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1982 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1983 			goto decrease_sf_crcount;
1984 
1985 		/* clear marks on query responses */
1986 		if (isquery)
1987 			psf->sf_gsresp = 0;
1988 
1989 		if (AVAILABLE(skb) < sizeof(*psrc) +
1990 		    first*sizeof(struct mld2_grec)) {
1991 			if (truncate && !first)
1992 				break;	 /* truncate these */
1993 			if (pgr)
1994 				pgr->grec_nsrcs = htons(scount);
1995 			if (skb)
1996 				mld_sendpack(skb);
1997 			skb = mld_newpack(idev, mtu);
1998 			first = 1;
1999 			scount = 0;
2000 		}
2001 		if (first) {
2002 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
2003 			first = 0;
2004 		}
2005 		if (!skb)
2006 			return NULL;
2007 		psrc = skb_put(skb, sizeof(*psrc));
2008 		*psrc = psf->sf_addr;
2009 		scount++; stotal++;
2010 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
2011 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
2012 decrease_sf_crcount:
2013 			psf->sf_crcount--;
2014 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
2015 				if (psf_prev)
2016 					rcu_assign_pointer(psf_prev->sf_next,
2017 							   mc_dereference(psf->sf_next, idev));
2018 				else
2019 					rcu_assign_pointer(*psf_list,
2020 							   mc_dereference(psf->sf_next, idev));
2021 				kfree_rcu(psf, rcu);
2022 				continue;
2023 			}
2024 		}
2025 		psf_prev = psf;
2026 	}
2027 
2028 empty_source:
2029 	if (!stotal) {
2030 		if (type == MLD2_ALLOW_NEW_SOURCES ||
2031 		    type == MLD2_BLOCK_OLD_SOURCES)
2032 			return skb;
2033 		if (pmc->mca_crcount || isquery || crsend) {
2034 			/* make sure we have room for group header */
2035 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
2036 				mld_sendpack(skb);
2037 				skb = NULL; /* add_grhead will get a new one */
2038 			}
2039 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
2040 		}
2041 	}
2042 	if (pgr)
2043 		pgr->grec_nsrcs = htons(scount);
2044 
2045 	if (isquery) {
2046 		/* clear query state */
2047 		WRITE_ONCE(pmc->mca_flags, pmc->mca_flags & ~MAF_GSQUERY);
2048 	}
2049 	return skb;
2050 }
2051 
2052 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
2053 {
2054 	struct sk_buff *skb = NULL;
2055 	int type;
2056 
2057 	mc_assert_locked(idev);
2058 
2059 	if (!pmc) {
2060 		for_each_mc_mclock(idev, pmc) {
2061 			if (pmc->mca_flags & MAF_NOREPORT)
2062 				continue;
2063 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
2064 				type = MLD2_MODE_IS_EXCLUDE;
2065 			else
2066 				type = MLD2_MODE_IS_INCLUDE;
2067 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2068 		}
2069 	} else {
2070 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2071 			type = MLD2_MODE_IS_EXCLUDE;
2072 		else
2073 			type = MLD2_MODE_IS_INCLUDE;
2074 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2075 	}
2076 	if (skb)
2077 		mld_sendpack(skb);
2078 }
2079 
2080 /* remove zero-count source records from a source filter list */
2081 static void mld_clear_zeros(struct ip6_sf_list __rcu **ppsf, struct inet6_dev *idev)
2082 {
2083 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
2084 
2085 	psf_prev = NULL;
2086 	for (psf = mc_dereference(*ppsf, idev);
2087 	     psf;
2088 	     psf = psf_next) {
2089 		psf_next = mc_dereference(psf->sf_next, idev);
2090 		if (psf->sf_crcount == 0) {
2091 			if (psf_prev)
2092 				rcu_assign_pointer(psf_prev->sf_next,
2093 						   mc_dereference(psf->sf_next, idev));
2094 			else
2095 				rcu_assign_pointer(*ppsf,
2096 						   mc_dereference(psf->sf_next, idev));
2097 			kfree_rcu(psf, rcu);
2098 		} else {
2099 			psf_prev = psf;
2100 		}
2101 	}
2102 }
2103 
2104 static void mld_send_cr(struct inet6_dev *idev)
2105 {
2106 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
2107 	struct sk_buff *skb = NULL;
2108 	int type, dtype;
2109 
2110 	/* deleted MCA's */
2111 	pmc_prev = NULL;
2112 	for (pmc = mc_dereference(idev->mc_tomb, idev);
2113 	     pmc;
2114 	     pmc = pmc_next) {
2115 		pmc_next = mc_dereference(pmc->next, idev);
2116 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
2117 			type = MLD2_BLOCK_OLD_SOURCES;
2118 			dtype = MLD2_BLOCK_OLD_SOURCES;
2119 			skb = add_grec(skb, pmc, type, 1, 0, 0);
2120 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
2121 		}
2122 		if (pmc->mca_crcount) {
2123 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
2124 				type = MLD2_CHANGE_TO_INCLUDE;
2125 				skb = add_grec(skb, pmc, type, 1, 0, 0);
2126 			}
2127 			pmc->mca_crcount--;
2128 			if (pmc->mca_crcount == 0) {
2129 				mld_clear_zeros(&pmc->mca_tomb, idev);
2130 				mld_clear_zeros(&pmc->mca_sources, idev);
2131 			}
2132 		}
2133 		if (pmc->mca_crcount == 0 &&
2134 		    !rcu_access_pointer(pmc->mca_tomb) &&
2135 		    !rcu_access_pointer(pmc->mca_sources)) {
2136 			if (pmc_prev)
2137 				rcu_assign_pointer(pmc_prev->next, pmc_next);
2138 			else
2139 				rcu_assign_pointer(idev->mc_tomb, pmc_next);
2140 			in6_dev_put(pmc->idev);
2141 			kfree_rcu(pmc, rcu);
2142 		} else
2143 			pmc_prev = pmc;
2144 	}
2145 
2146 	/* change recs */
2147 	for_each_mc_mclock(idev, pmc) {
2148 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2149 			type = MLD2_BLOCK_OLD_SOURCES;
2150 			dtype = MLD2_ALLOW_NEW_SOURCES;
2151 		} else {
2152 			type = MLD2_ALLOW_NEW_SOURCES;
2153 			dtype = MLD2_BLOCK_OLD_SOURCES;
2154 		}
2155 		skb = add_grec(skb, pmc, type, 0, 0, 0);
2156 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
2157 
2158 		/* filter mode changes */
2159 		if (pmc->mca_crcount) {
2160 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
2161 				type = MLD2_CHANGE_TO_EXCLUDE;
2162 			else
2163 				type = MLD2_CHANGE_TO_INCLUDE;
2164 			skb = add_grec(skb, pmc, type, 0, 0, 0);
2165 			pmc->mca_crcount--;
2166 		}
2167 	}
2168 	if (!skb)
2169 		return;
2170 	(void) mld_sendpack(skb);
2171 }
2172 
2173 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
2174 {
2175 	const struct in6_addr *snd_addr, *saddr;
2176 	int err, len, payload_len, full_len;
2177 	struct in6_addr addr_buf;
2178 	struct inet6_dev *idev;
2179 	struct sk_buff *skb;
2180 	struct mld_msg *hdr;
2181 	int hlen = LL_RESERVED_SPACE(dev);
2182 	int tlen = dev->needed_tailroom;
2183 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
2184 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
2185 		     IPV6_TLV_PADN, 0 };
2186 	struct dst_entry *dst;
2187 	struct flowi6 fl6;
2188 	struct net *net;
2189 	struct sock *sk;
2190 
2191 	if (type == ICMPV6_MGM_REDUCTION)
2192 		snd_addr = &in6addr_linklocal_allrouters;
2193 	else
2194 		snd_addr = addr;
2195 
2196 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2197 	payload_len = len + sizeof(ra);
2198 	full_len = sizeof(struct ipv6hdr) + payload_len;
2199 
2200 	skb = alloc_skb(hlen + tlen + full_len, GFP_KERNEL);
2201 
2202 	rcu_read_lock();
2203 
2204 	net = dev_net_rcu(dev);
2205 	idev = __in6_dev_get(dev);
2206 	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
2207 	if (!skb) {
2208 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2209 		rcu_read_unlock();
2210 		return;
2211 	}
2212 	sk = net->ipv6.igmp_sk;
2213 	skb_set_owner_w(skb, sk);
2214 
2215 	skb->priority = TC_PRIO_CONTROL;
2216 	skb_reserve(skb, hlen);
2217 
2218 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2219 		/* <draft-ietf-magma-mld-source-05.txt>:
2220 		 * use unspecified address as the source address
2221 		 * when a valid link-local address is not available.
2222 		 */
2223 		saddr = &in6addr_any;
2224 	} else
2225 		saddr = &addr_buf;
2226 
2227 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2228 
2229 	skb_put_data(skb, ra, sizeof(ra));
2230 
2231 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2232 	hdr->mld_type = type;
2233 	hdr->mld_mca = *addr;
2234 
2235 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2236 					 IPPROTO_ICMPV6,
2237 					 csum_partial(hdr, len, 0));
2238 
2239 	icmpv6_flow_init(sk, &fl6, type,
2240 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2241 			 skb->dev->ifindex);
2242 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2243 	if (IS_ERR(dst)) {
2244 		err = PTR_ERR(dst);
2245 		goto err_out;
2246 	}
2247 
2248 	skb_dst_set(skb, dst);
2249 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2250 		      net, sk, skb, NULL, skb->dev,
2251 		      dst_output);
2252 out:
2253 	if (!err) {
2254 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2255 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2256 	} else
2257 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2258 
2259 	rcu_read_unlock();
2260 	return;
2261 
2262 err_out:
2263 	kfree_skb(skb);
2264 	goto out;
2265 }
2266 
2267 static void mld_send_initial_cr(struct inet6_dev *idev)
2268 {
2269 	struct ifmcaddr6 *pmc;
2270 	struct sk_buff *skb;
2271 	int type;
2272 
2273 	mc_assert_locked(idev);
2274 
2275 	if (mld_in_v1_mode(idev))
2276 		return;
2277 
2278 	skb = NULL;
2279 	for_each_mc_mclock(idev, pmc) {
2280 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2281 			type = MLD2_CHANGE_TO_EXCLUDE;
2282 		else
2283 			type = MLD2_ALLOW_NEW_SOURCES;
2284 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2285 	}
2286 	if (skb)
2287 		mld_sendpack(skb);
2288 }
2289 
2290 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2291 {
2292 	mutex_lock(&idev->mc_lock);
2293 	idev->mc_dad_count = idev->mc_qrv;
2294 	if (idev->mc_dad_count) {
2295 		mld_send_initial_cr(idev);
2296 		idev->mc_dad_count--;
2297 		if (idev->mc_dad_count)
2298 			mld_dad_start_work(idev,
2299 					   unsolicited_report_interval(idev));
2300 	}
2301 	mutex_unlock(&idev->mc_lock);
2302 }
2303 
2304 static void mld_dad_work(struct work_struct *work)
2305 {
2306 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2307 					      struct inet6_dev,
2308 					      mc_dad_work);
2309 	mutex_lock(&idev->mc_lock);
2310 	mld_send_initial_cr(idev);
2311 	if (idev->mc_dad_count) {
2312 		idev->mc_dad_count--;
2313 		if (idev->mc_dad_count)
2314 			mld_dad_start_work(idev,
2315 					   unsolicited_report_interval(idev));
2316 	}
2317 	mutex_unlock(&idev->mc_lock);
2318 	in6_dev_put(idev);
2319 }
2320 
2321 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2322 			   const struct in6_addr *psfsrc)
2323 {
2324 	struct ip6_sf_list *psf, *psf_prev;
2325 	int rv = 0;
2326 
2327 	mc_assert_locked(pmc->idev);
2328 
2329 	psf_prev = NULL;
2330 	for_each_psf_mclock(pmc, psf) {
2331 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2332 			break;
2333 		psf_prev = psf;
2334 	}
2335 	if (!psf || psf->sf_count[sfmode] == 0) {
2336 		/* source filter not found, or count wrong =>  bug */
2337 		return -ESRCH;
2338 	}
2339 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] - 1);
2340 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2341 		struct inet6_dev *idev = pmc->idev;
2342 
2343 		/* no more filters for this source */
2344 		if (psf_prev)
2345 			rcu_assign_pointer(psf_prev->sf_next,
2346 					   mc_dereference(psf->sf_next, idev));
2347 		else
2348 			rcu_assign_pointer(pmc->mca_sources,
2349 					   mc_dereference(psf->sf_next, idev));
2350 
2351 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2352 		    !mld_in_v1_mode(idev)) {
2353 			psf->sf_crcount = idev->mc_qrv;
2354 			rcu_assign_pointer(psf->sf_next,
2355 					   mc_dereference(pmc->mca_tomb, idev));
2356 			rcu_assign_pointer(pmc->mca_tomb, psf);
2357 			rv = 1;
2358 		} else {
2359 			kfree_rcu(psf, rcu);
2360 		}
2361 	}
2362 	return rv;
2363 }
2364 
2365 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2366 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2367 			  int delta)
2368 {
2369 	struct ifmcaddr6 *pmc;
2370 	int	changerec = 0;
2371 	int	i, err;
2372 
2373 	if (!idev)
2374 		return -ENODEV;
2375 
2376 	mc_assert_locked(idev);
2377 
2378 	for_each_mc_mclock(idev, pmc) {
2379 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2380 			break;
2381 	}
2382 	if (!pmc)
2383 		return -ESRCH;
2384 
2385 	sf_markstate(pmc);
2386 	if (!delta) {
2387 		if (!pmc->mca_sfcount[sfmode])
2388 			return -EINVAL;
2389 
2390 		pmc->mca_sfcount[sfmode]--;
2391 	}
2392 	err = 0;
2393 	for (i = 0; i < sfcount; i++) {
2394 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2395 
2396 		changerec |= rv > 0;
2397 		if (!err && rv < 0)
2398 			err = rv;
2399 	}
2400 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2401 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2402 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2403 		struct ip6_sf_list *psf;
2404 
2405 		/* filter mode change */
2406 		pmc->mca_sfmode = MCAST_INCLUDE;
2407 		pmc->mca_crcount = idev->mc_qrv;
2408 		idev->mc_ifc_count = pmc->mca_crcount;
2409 		for_each_psf_mclock(pmc, psf)
2410 			psf->sf_crcount = 0;
2411 		mld_ifc_event(pmc->idev);
2412 	} else if (sf_setstate(pmc) || changerec) {
2413 		mld_ifc_event(pmc->idev);
2414 	}
2415 
2416 	return err;
2417 }
2418 
2419 /* Add multicast single-source filter to the interface list */
2420 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2421 			   const struct in6_addr *psfsrc)
2422 {
2423 	struct ip6_sf_list *psf, *psf_prev;
2424 
2425 	mc_assert_locked(pmc->idev);
2426 
2427 	psf_prev = NULL;
2428 	for_each_psf_mclock(pmc, psf) {
2429 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2430 			break;
2431 		psf_prev = psf;
2432 	}
2433 	if (!psf) {
2434 		psf = kzalloc_obj(*psf);
2435 		if (!psf)
2436 			return -ENOBUFS;
2437 
2438 		psf->sf_addr = *psfsrc;
2439 		if (psf_prev) {
2440 			rcu_assign_pointer(psf_prev->sf_next, psf);
2441 		} else {
2442 			rcu_assign_pointer(pmc->mca_sources, psf);
2443 		}
2444 	}
2445 	WRITE_ONCE(psf->sf_count[sfmode], psf->sf_count[sfmode] + 1);
2446 	return 0;
2447 }
2448 
2449 static void sf_markstate(struct ifmcaddr6 *pmc)
2450 {
2451 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2452 	struct ip6_sf_list *psf;
2453 
2454 	mc_assert_locked(pmc->idev);
2455 
2456 	for_each_psf_mclock(pmc, psf) {
2457 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2458 			psf->sf_oldin = mca_xcount ==
2459 				psf->sf_count[MCAST_EXCLUDE] &&
2460 				!psf->sf_count[MCAST_INCLUDE];
2461 		} else {
2462 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2463 		}
2464 	}
2465 }
2466 
2467 static int sf_setstate(struct ifmcaddr6 *pmc)
2468 {
2469 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2470 	struct ip6_sf_list *psf, *dpsf;
2471 	int qrv = pmc->idev->mc_qrv;
2472 	int new_in, rv;
2473 
2474 	mc_assert_locked(pmc->idev);
2475 
2476 	rv = 0;
2477 	for_each_psf_mclock(pmc, psf) {
2478 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2479 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2480 				!psf->sf_count[MCAST_INCLUDE];
2481 		} else
2482 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2483 		if (new_in) {
2484 			if (!psf->sf_oldin) {
2485 				struct ip6_sf_list *prev = NULL;
2486 
2487 				for_each_psf_tomb(pmc, dpsf) {
2488 					if (ipv6_addr_equal(&dpsf->sf_addr,
2489 					    &psf->sf_addr))
2490 						break;
2491 					prev = dpsf;
2492 				}
2493 				if (dpsf) {
2494 					if (prev)
2495 						rcu_assign_pointer(prev->sf_next,
2496 								   mc_dereference(dpsf->sf_next,
2497 										  pmc->idev));
2498 					else
2499 						rcu_assign_pointer(pmc->mca_tomb,
2500 								   mc_dereference(dpsf->sf_next,
2501 										  pmc->idev));
2502 					kfree_rcu(dpsf, rcu);
2503 				}
2504 				psf->sf_crcount = qrv;
2505 				rv++;
2506 			}
2507 		} else if (psf->sf_oldin) {
2508 			psf->sf_crcount = 0;
2509 			/*
2510 			 * add or update "delete" records if an active filter
2511 			 * is now inactive
2512 			 */
2513 
2514 			for_each_psf_tomb(pmc, dpsf)
2515 				if (ipv6_addr_equal(&dpsf->sf_addr,
2516 				    &psf->sf_addr))
2517 					break;
2518 			if (!dpsf) {
2519 				dpsf = kmalloc_obj(*dpsf);
2520 				if (!dpsf)
2521 					continue;
2522 				*dpsf = *psf;
2523 				rcu_assign_pointer(dpsf->sf_next,
2524 						   mc_dereference(pmc->mca_tomb, pmc->idev));
2525 				rcu_assign_pointer(pmc->mca_tomb, dpsf);
2526 			}
2527 			dpsf->sf_crcount = qrv;
2528 			rv++;
2529 		}
2530 	}
2531 	return rv;
2532 }
2533 
2534 /* Add multicast source filter list to the interface list */
2535 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2536 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2537 			  int delta)
2538 {
2539 	struct ifmcaddr6 *pmc;
2540 	int	isexclude;
2541 	int	i, err;
2542 
2543 	if (!idev)
2544 		return -ENODEV;
2545 
2546 	mc_assert_locked(idev);
2547 
2548 	for_each_mc_mclock(idev, pmc) {
2549 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2550 			break;
2551 	}
2552 	if (!pmc)
2553 		return -ESRCH;
2554 
2555 	sf_markstate(pmc);
2556 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2557 	if (!delta)
2558 		WRITE_ONCE(pmc->mca_sfcount[sfmode],
2559 			   pmc->mca_sfcount[sfmode] + 1);
2560 	err = 0;
2561 	for (i = 0; i < sfcount; i++) {
2562 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2563 		if (err)
2564 			break;
2565 	}
2566 	if (err) {
2567 		int j;
2568 
2569 		if (!delta)
2570 			WRITE_ONCE(pmc->mca_sfcount[sfmode],
2571 				   pmc->mca_sfcount[sfmode] - 1);
2572 		for (j = 0; j < i; j++)
2573 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2574 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2575 		struct ip6_sf_list *psf;
2576 
2577 		/* filter mode change */
2578 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2579 			pmc->mca_sfmode = MCAST_EXCLUDE;
2580 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2581 			pmc->mca_sfmode = MCAST_INCLUDE;
2582 		/* else no filters; keep old mode for reports */
2583 
2584 		pmc->mca_crcount = idev->mc_qrv;
2585 		idev->mc_ifc_count = pmc->mca_crcount;
2586 		for_each_psf_mclock(pmc, psf)
2587 			psf->sf_crcount = 0;
2588 		mld_ifc_event(idev);
2589 	} else if (sf_setstate(pmc)) {
2590 		mld_ifc_event(idev);
2591 	}
2592 	return err;
2593 }
2594 
2595 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2596 {
2597 	struct ip6_sf_list *psf, *nextpsf;
2598 
2599 	mc_assert_locked(pmc->idev);
2600 
2601 	for (psf = mc_dereference(pmc->mca_tomb, pmc->idev);
2602 	     psf;
2603 	     psf = nextpsf) {
2604 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2605 		kfree_rcu(psf, rcu);
2606 	}
2607 	RCU_INIT_POINTER(pmc->mca_tomb, NULL);
2608 	for (psf = mc_dereference(pmc->mca_sources, pmc->idev);
2609 	     psf;
2610 	     psf = nextpsf) {
2611 		nextpsf = mc_dereference(psf->sf_next, pmc->idev);
2612 		kfree_rcu(psf, rcu);
2613 	}
2614 	RCU_INIT_POINTER(pmc->mca_sources, NULL);
2615 	pmc->mca_sfmode = MCAST_EXCLUDE;
2616 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2617 	/* Paired with the READ_ONCE() from ipv6_chk_mcast_addr() */
2618 	WRITE_ONCE(pmc->mca_sfcount[MCAST_EXCLUDE], 1);
2619 }
2620 
2621 static void igmp6_join_group(struct ifmcaddr6 *ma)
2622 {
2623 	unsigned long delay;
2624 
2625 	mc_assert_locked(ma->idev);
2626 
2627 	if (ma->mca_flags & MAF_NOREPORT)
2628 		return;
2629 
2630 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2631 
2632 	delay = get_random_u32_below(unsolicited_report_interval(ma->idev));
2633 
2634 	if (cancel_delayed_work(&ma->mca_work)) {
2635 		refcount_dec(&ma->mca_refcnt);
2636 		delay = ma->mca_work.timer.expires - jiffies;
2637 	}
2638 
2639 	if (!mod_delayed_work(mld_wq, &ma->mca_work, delay))
2640 		refcount_inc(&ma->mca_refcnt);
2641 	WRITE_ONCE(ma->mca_flags, ma->mca_flags |
2642 		   MAF_TIMER_RUNNING | MAF_LAST_REPORTER);
2643 }
2644 
2645 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2646 			    struct inet6_dev *idev)
2647 {
2648 	struct ip6_sf_socklist *psl;
2649 	int err;
2650 
2651 	psl = sock_dereference(iml->sflist, sk);
2652 
2653 	if (idev)
2654 		mutex_lock(&idev->mc_lock);
2655 
2656 	if (!psl) {
2657 		/* any-source empty exclude case */
2658 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2659 	} else {
2660 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2661 				     psl->sl_count, psl->sl_addr, 0);
2662 		RCU_INIT_POINTER(iml->sflist, NULL);
2663 		atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
2664 			   &sk->sk_omem_alloc);
2665 		kfree_rcu(psl, rcu);
2666 	}
2667 
2668 	if (idev)
2669 		mutex_unlock(&idev->mc_lock);
2670 
2671 	return err;
2672 }
2673 
2674 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2675 {
2676 	mc_assert_locked(ma->idev);
2677 
2678 	if (mld_in_v1_mode(ma->idev)) {
2679 		if (ma->mca_flags & MAF_LAST_REPORTER) {
2680 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2681 				ICMPV6_MGM_REDUCTION);
2682 		}
2683 	} else {
2684 		mld_add_delrec(ma->idev, ma);
2685 		mld_ifc_event(ma->idev);
2686 	}
2687 }
2688 
2689 static void mld_gq_work(struct work_struct *work)
2690 {
2691 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2692 					      struct inet6_dev,
2693 					      mc_gq_work);
2694 
2695 	mutex_lock(&idev->mc_lock);
2696 	mld_send_report(idev, NULL);
2697 	idev->mc_gq_running = 0;
2698 	mutex_unlock(&idev->mc_lock);
2699 
2700 	in6_dev_put(idev);
2701 }
2702 
2703 static void mld_ifc_work(struct work_struct *work)
2704 {
2705 	struct inet6_dev *idev = container_of(to_delayed_work(work),
2706 					      struct inet6_dev,
2707 					      mc_ifc_work);
2708 
2709 	mutex_lock(&idev->mc_lock);
2710 	mld_send_cr(idev);
2711 
2712 	if (idev->mc_ifc_count) {
2713 		idev->mc_ifc_count--;
2714 		if (idev->mc_ifc_count)
2715 			mld_ifc_start_work(idev,
2716 					   unsolicited_report_interval(idev));
2717 	}
2718 	mutex_unlock(&idev->mc_lock);
2719 	in6_dev_put(idev);
2720 }
2721 
2722 static void mld_ifc_event(struct inet6_dev *idev)
2723 {
2724 	mc_assert_locked(idev);
2725 
2726 	if (mld_in_v1_mode(idev))
2727 		return;
2728 
2729 	idev->mc_ifc_count = idev->mc_qrv;
2730 	mld_ifc_start_work(idev, 1);
2731 }
2732 
2733 static void mld_mca_work(struct work_struct *work)
2734 {
2735 	struct ifmcaddr6 *ma = container_of(to_delayed_work(work),
2736 					    struct ifmcaddr6, mca_work);
2737 
2738 	mutex_lock(&ma->idev->mc_lock);
2739 	if (mld_in_v1_mode(ma->idev))
2740 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2741 	else
2742 		mld_send_report(ma->idev, ma);
2743 	WRITE_ONCE(ma->mca_flags, (ma->mca_flags | MAF_LAST_REPORTER) &
2744 		   ~MAF_TIMER_RUNNING);
2745 	mutex_unlock(&ma->idev->mc_lock);
2746 
2747 	ma_put(ma);
2748 }
2749 
2750 /* Device changing type */
2751 
2752 void ipv6_mc_unmap(struct inet6_dev *idev)
2753 {
2754 	struct ifmcaddr6 *i;
2755 
2756 	/* Install multicast list, except for all-nodes (already installed) */
2757 
2758 	mutex_lock(&idev->mc_lock);
2759 	for_each_mc_mclock(idev, i)
2760 		igmp6_group_dropped(i);
2761 	mutex_unlock(&idev->mc_lock);
2762 }
2763 
2764 void ipv6_mc_remap(struct inet6_dev *idev)
2765 {
2766 	ipv6_mc_up(idev);
2767 }
2768 
2769 /* Device going down */
2770 void ipv6_mc_down(struct inet6_dev *idev)
2771 {
2772 	struct ifmcaddr6 *i;
2773 
2774 	mutex_lock(&idev->mc_lock);
2775 	/* Withdraw multicast list */
2776 	for_each_mc_mclock(idev, i)
2777 		igmp6_group_dropped(i);
2778 	mutex_unlock(&idev->mc_lock);
2779 
2780 	/* Should stop work after group drop. or we will
2781 	 * start work again in mld_ifc_event()
2782 	 */
2783 	mld_query_stop_work(idev);
2784 	mld_report_stop_work(idev);
2785 
2786 	mutex_lock(&idev->mc_lock);
2787 	mld_ifc_stop_work(idev);
2788 	mld_gq_stop_work(idev);
2789 	mutex_unlock(&idev->mc_lock);
2790 
2791 	mld_dad_stop_work(idev);
2792 }
2793 
2794 static void ipv6_mc_reset(struct inet6_dev *idev)
2795 {
2796 	idev->mc_qrv = sysctl_mld_qrv;
2797 	idev->mc_qi = MLD_QI_DEFAULT;
2798 	idev->mc_qri = MLD_QRI_DEFAULT;
2799 	idev->mc_v1_seen = 0;
2800 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2801 }
2802 
2803 /* Device going up */
2804 
2805 void ipv6_mc_up(struct inet6_dev *idev)
2806 {
2807 	struct ifmcaddr6 *i;
2808 
2809 	/* Install multicast list, except for all-nodes (already installed) */
2810 
2811 	ipv6_mc_reset(idev);
2812 	mutex_lock(&idev->mc_lock);
2813 	for_each_mc_mclock(idev, i) {
2814 		mld_del_delrec(idev, i);
2815 		igmp6_group_added(i);
2816 	}
2817 	mutex_unlock(&idev->mc_lock);
2818 }
2819 
2820 /* IPv6 device initialization. */
2821 
2822 void ipv6_mc_init_dev(struct inet6_dev *idev)
2823 {
2824 	idev->mc_gq_running = 0;
2825 	INIT_DELAYED_WORK(&idev->mc_gq_work, mld_gq_work);
2826 	RCU_INIT_POINTER(idev->mc_tomb, NULL);
2827 	idev->mc_ifc_count = 0;
2828 	INIT_DELAYED_WORK(&idev->mc_ifc_work, mld_ifc_work);
2829 	INIT_DELAYED_WORK(&idev->mc_dad_work, mld_dad_work);
2830 	INIT_DELAYED_WORK(&idev->mc_query_work, mld_query_work);
2831 	INIT_DELAYED_WORK(&idev->mc_report_work, mld_report_work);
2832 	skb_queue_head_init(&idev->mc_query_queue);
2833 	skb_queue_head_init(&idev->mc_report_queue);
2834 	spin_lock_init(&idev->mc_query_lock);
2835 	spin_lock_init(&idev->mc_report_lock);
2836 	mutex_init(&idev->mc_lock);
2837 	ipv6_mc_reset(idev);
2838 }
2839 
2840 /*
2841  *	Device is about to be destroyed: clean up.
2842  */
2843 
2844 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2845 {
2846 	struct ifmcaddr6 *i;
2847 
2848 	/* Deactivate works */
2849 	ipv6_mc_down(idev);
2850 	mutex_lock(&idev->mc_lock);
2851 	mld_clear_delrec(idev);
2852 	mutex_unlock(&idev->mc_lock);
2853 	mld_clear_query(idev);
2854 	mld_clear_report(idev);
2855 
2856 	/* Delete all-nodes address. */
2857 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2858 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2859 	 * fail.
2860 	 */
2861 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2862 
2863 	if (idev->cnf.forwarding)
2864 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2865 
2866 	mutex_lock(&idev->mc_lock);
2867 	while ((i = mc_dereference(idev->mc_list, idev))) {
2868 		rcu_assign_pointer(idev->mc_list, mc_dereference(i->next, idev));
2869 
2870 		ip6_mc_clear_src(i);
2871 		ma_put(i);
2872 	}
2873 	mutex_unlock(&idev->mc_lock);
2874 }
2875 
2876 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2877 {
2878 	struct ifmcaddr6 *pmc;
2879 
2880 	mutex_lock(&idev->mc_lock);
2881 	if (mld_in_v1_mode(idev)) {
2882 		for_each_mc_mclock(idev, pmc)
2883 			igmp6_join_group(pmc);
2884 	} else {
2885 		mld_send_report(idev, NULL);
2886 	}
2887 	mutex_unlock(&idev->mc_lock);
2888 }
2889 
2890 static int ipv6_mc_netdev_event(struct notifier_block *this,
2891 				unsigned long event,
2892 				void *ptr)
2893 {
2894 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2895 	struct inet6_dev *idev = __in6_dev_get(dev);
2896 
2897 	switch (event) {
2898 	case NETDEV_RESEND_IGMP:
2899 		if (idev)
2900 			ipv6_mc_rejoin_groups(idev);
2901 		break;
2902 	default:
2903 		break;
2904 	}
2905 
2906 	return NOTIFY_DONE;
2907 }
2908 
2909 static struct notifier_block igmp6_netdev_notifier = {
2910 	.notifier_call = ipv6_mc_netdev_event,
2911 };
2912 
2913 #ifdef CONFIG_PROC_FS
2914 struct igmp6_mc_iter_state {
2915 	struct seq_net_private p;
2916 	struct net_device *dev;
2917 	struct inet6_dev *idev;
2918 };
2919 
2920 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2921 
2922 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2923 {
2924 	struct ifmcaddr6 *im = NULL;
2925 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2926 	struct net *net = seq_file_net(seq);
2927 
2928 	state->idev = NULL;
2929 	for_each_netdev_rcu(net, state->dev) {
2930 		struct inet6_dev *idev;
2931 		idev = __in6_dev_get(state->dev);
2932 		if (!idev)
2933 			continue;
2934 
2935 		im = rcu_dereference(idev->mc_list);
2936 		if (im) {
2937 			state->idev = idev;
2938 			break;
2939 		}
2940 	}
2941 	return im;
2942 }
2943 
2944 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2945 {
2946 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2947 
2948 	im = rcu_dereference(im->next);
2949 	while (!im) {
2950 		state->dev = next_net_device_rcu(state->dev);
2951 		if (!state->dev) {
2952 			state->idev = NULL;
2953 			break;
2954 		}
2955 		state->idev = __in6_dev_get(state->dev);
2956 		if (!state->idev)
2957 			continue;
2958 		im = rcu_dereference(state->idev->mc_list);
2959 	}
2960 	return im;
2961 }
2962 
2963 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2964 {
2965 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2966 	if (im)
2967 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2968 			--pos;
2969 	return pos ? NULL : im;
2970 }
2971 
2972 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2973 	__acquires(RCU)
2974 {
2975 	rcu_read_lock();
2976 	return igmp6_mc_get_idx(seq, *pos);
2977 }
2978 
2979 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2980 {
2981 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2982 
2983 	++*pos;
2984 	return im;
2985 }
2986 
2987 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2988 	__releases(RCU)
2989 {
2990 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2991 
2992 	if (likely(state->idev))
2993 		state->idev = NULL;
2994 	state->dev = NULL;
2995 	rcu_read_unlock();
2996 }
2997 
2998 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2999 {
3000 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
3001 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
3002 	unsigned int mca_flags = READ_ONCE(im->mca_flags);
3003 	unsigned long expires = READ_ONCE(im->mca_work.timer.expires);
3004 
3005 	seq_printf(seq,
3006 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
3007 		   state->dev->ifindex, state->dev->name,
3008 		   &im->mca_addr,
3009 		   READ_ONCE(im->mca_users), mca_flags,
3010 		   (mca_flags & MAF_TIMER_RUNNING) ?
3011 		   jiffies_to_clock_t(expires - jiffies) : 0);
3012 	return 0;
3013 }
3014 
3015 static const struct seq_operations igmp6_mc_seq_ops = {
3016 	.start	=	igmp6_mc_seq_start,
3017 	.next	=	igmp6_mc_seq_next,
3018 	.stop	=	igmp6_mc_seq_stop,
3019 	.show	=	igmp6_mc_seq_show,
3020 };
3021 
3022 struct igmp6_mcf_iter_state {
3023 	struct seq_net_private p;
3024 	struct net_device *dev;
3025 	struct inet6_dev *idev;
3026 	struct ifmcaddr6 *im;
3027 };
3028 
3029 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
3030 
3031 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
3032 {
3033 	struct ip6_sf_list *psf = NULL;
3034 	struct ifmcaddr6 *im = NULL;
3035 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3036 	struct net *net = seq_file_net(seq);
3037 
3038 	state->idev = NULL;
3039 	state->im = NULL;
3040 	for_each_netdev_rcu(net, state->dev) {
3041 		struct inet6_dev *idev;
3042 		idev = __in6_dev_get(state->dev);
3043 		if (unlikely(idev == NULL))
3044 			continue;
3045 
3046 		im = rcu_dereference(idev->mc_list);
3047 		if (likely(im)) {
3048 			psf = rcu_dereference(im->mca_sources);
3049 			if (likely(psf)) {
3050 				state->im = im;
3051 				state->idev = idev;
3052 				break;
3053 			}
3054 		}
3055 	}
3056 	return psf;
3057 }
3058 
3059 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
3060 {
3061 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3062 
3063 	psf = rcu_dereference(psf->sf_next);
3064 	while (!psf) {
3065 		state->im = rcu_dereference(state->im->next);
3066 		while (!state->im) {
3067 			state->dev = next_net_device_rcu(state->dev);
3068 			if (!state->dev) {
3069 				state->idev = NULL;
3070 				goto out;
3071 			}
3072 			state->idev = __in6_dev_get(state->dev);
3073 			if (!state->idev)
3074 				continue;
3075 			state->im = rcu_dereference(state->idev->mc_list);
3076 		}
3077 		psf = rcu_dereference(state->im->mca_sources);
3078 	}
3079 out:
3080 	return psf;
3081 }
3082 
3083 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
3084 {
3085 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
3086 	if (psf)
3087 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
3088 			--pos;
3089 	return pos ? NULL : psf;
3090 }
3091 
3092 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
3093 	__acquires(RCU)
3094 {
3095 	rcu_read_lock();
3096 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
3097 }
3098 
3099 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3100 {
3101 	struct ip6_sf_list *psf;
3102 	if (v == SEQ_START_TOKEN)
3103 		psf = igmp6_mcf_get_first(seq);
3104 	else
3105 		psf = igmp6_mcf_get_next(seq, v);
3106 	++*pos;
3107 	return psf;
3108 }
3109 
3110 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
3111 	__releases(RCU)
3112 {
3113 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3114 
3115 	if (likely(state->im))
3116 		state->im = NULL;
3117 	if (likely(state->idev))
3118 		state->idev = NULL;
3119 
3120 	state->dev = NULL;
3121 	rcu_read_unlock();
3122 }
3123 
3124 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
3125 {
3126 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
3127 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
3128 
3129 	if (v == SEQ_START_TOKEN) {
3130 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
3131 	} else {
3132 		seq_printf(seq,
3133 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
3134 			   state->dev->ifindex, state->dev->name,
3135 			   &state->im->mca_addr,
3136 			   &psf->sf_addr,
3137 			   READ_ONCE(psf->sf_count[MCAST_INCLUDE]),
3138 			   READ_ONCE(psf->sf_count[MCAST_EXCLUDE]));
3139 	}
3140 	return 0;
3141 }
3142 
3143 static const struct seq_operations igmp6_mcf_seq_ops = {
3144 	.start	=	igmp6_mcf_seq_start,
3145 	.next	=	igmp6_mcf_seq_next,
3146 	.stop	=	igmp6_mcf_seq_stop,
3147 	.show	=	igmp6_mcf_seq_show,
3148 };
3149 
3150 static int __net_init igmp6_proc_init(struct net *net)
3151 {
3152 	int err;
3153 
3154 	err = -ENOMEM;
3155 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
3156 			sizeof(struct igmp6_mc_iter_state)))
3157 		goto out;
3158 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
3159 			&igmp6_mcf_seq_ops,
3160 			sizeof(struct igmp6_mcf_iter_state)))
3161 		goto out_proc_net_igmp6;
3162 
3163 	err = 0;
3164 out:
3165 	return err;
3166 
3167 out_proc_net_igmp6:
3168 	remove_proc_entry("igmp6", net->proc_net);
3169 	goto out;
3170 }
3171 
3172 static void __net_exit igmp6_proc_exit(struct net *net)
3173 {
3174 	remove_proc_entry("mcfilter6", net->proc_net);
3175 	remove_proc_entry("igmp6", net->proc_net);
3176 }
3177 #else
3178 static inline int igmp6_proc_init(struct net *net)
3179 {
3180 	return 0;
3181 }
3182 static inline void igmp6_proc_exit(struct net *net)
3183 {
3184 }
3185 #endif
3186 
3187 static int __net_init igmp6_net_init(struct net *net)
3188 {
3189 	int err;
3190 
3191 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
3192 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3193 	if (err < 0) {
3194 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
3195 		       err);
3196 		goto out;
3197 	}
3198 
3199 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
3200 	net->ipv6.igmp_sk->sk_allocation = GFP_KERNEL;
3201 
3202 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
3203 				   SOCK_RAW, IPPROTO_ICMPV6, net);
3204 	if (err < 0) {
3205 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
3206 		       err);
3207 		goto out_sock_create;
3208 	}
3209 
3210 	err = igmp6_proc_init(net);
3211 	if (err)
3212 		goto out_sock_create_autojoin;
3213 
3214 	return 0;
3215 
3216 out_sock_create_autojoin:
3217 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3218 out_sock_create:
3219 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3220 out:
3221 	return err;
3222 }
3223 
3224 static void __net_exit igmp6_net_exit(struct net *net)
3225 {
3226 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
3227 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
3228 	igmp6_proc_exit(net);
3229 }
3230 
3231 static struct pernet_operations igmp6_net_ops = {
3232 	.init = igmp6_net_init,
3233 	.exit = igmp6_net_exit,
3234 };
3235 
3236 int __init igmp6_init(void)
3237 {
3238 	int err;
3239 
3240 	err = register_pernet_subsys(&igmp6_net_ops);
3241 	if (err)
3242 		return err;
3243 
3244 	mld_wq = create_workqueue("mld");
3245 	if (!mld_wq) {
3246 		unregister_pernet_subsys(&igmp6_net_ops);
3247 		return -ENOMEM;
3248 	}
3249 
3250 	return err;
3251 }
3252 
3253 int __init igmp6_late_init(void)
3254 {
3255 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3256 }
3257 
3258 void igmp6_cleanup(void)
3259 {
3260 	unregister_pernet_subsys(&igmp6_net_ops);
3261 	destroy_workqueue(mld_wq);
3262 }
3263 
3264 void igmp6_late_cleanup(void)
3265 {
3266 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3267 }
3268