xref: /openbmc/linux/net/ipv6/mcast.c (revision 5104d265)
1 /*
2  *	Multicast support for IPv6
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *
8  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
9  *
10  *	This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 /* Changes:
17  *
18  *	yoshfuji	: fix format of router-alert option
19  *	YOSHIFUJI Hideaki @USAGI:
20  *		Fixed source address for MLD message based on
21  *		<draft-ietf-magma-mld-source-05.txt>.
22  *	YOSHIFUJI Hideaki @USAGI:
23  *		- Ignore Queries for invalid addresses.
24  *		- MLD for link-local addresses.
25  *	David L Stevens <dlstevens@us.ibm.com>:
26  *		- MLDv2 support
27  */
28 
29 #include <linux/module.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/string.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/jiffies.h>
36 #include <linux/times.h>
37 #include <linux/net.h>
38 #include <linux/in.h>
39 #include <linux/in6.h>
40 #include <linux/netdevice.h>
41 #include <linux/if_arp.h>
42 #include <linux/route.h>
43 #include <linux/init.h>
44 #include <linux/proc_fs.h>
45 #include <linux/seq_file.h>
46 #include <linux/slab.h>
47 #include <net/mld.h>
48 
49 #include <linux/netfilter.h>
50 #include <linux/netfilter_ipv6.h>
51 
52 #include <net/net_namespace.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 /* Set to 3 to get tracing... */
67 #define MCAST_DEBUG 2
68 
69 #if MCAST_DEBUG >= 3
70 #define MDBG(x) printk x
71 #else
72 #define MDBG(x)
73 #endif
74 
75 /* Ensure that we have struct in6_addr aligned on 32bit word. */
76 static void *__mld2_query_bugs[] __attribute__((__unused__)) = {
77 	BUILD_BUG_ON_NULL(offsetof(struct mld2_query, mld2q_srcs) % 4),
78 	BUILD_BUG_ON_NULL(offsetof(struct mld2_report, mld2r_grec) % 4),
79 	BUILD_BUG_ON_NULL(offsetof(struct mld2_grec, grec_mca) % 4)
80 };
81 
82 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
83 
84 /* Big mc list lock for all the sockets */
85 static DEFINE_SPINLOCK(ipv6_sk_mc_lock);
86 
87 static void igmp6_join_group(struct ifmcaddr6 *ma);
88 static void igmp6_leave_group(struct ifmcaddr6 *ma);
89 static void igmp6_timer_handler(unsigned long data);
90 
91 static void mld_gq_timer_expire(unsigned long data);
92 static void mld_ifc_timer_expire(unsigned long data);
93 static void mld_ifc_event(struct inet6_dev *idev);
94 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
95 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *addr);
96 static void mld_clear_delrec(struct inet6_dev *idev);
97 static int sf_setstate(struct ifmcaddr6 *pmc);
98 static void sf_markstate(struct ifmcaddr6 *pmc);
99 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
100 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
101 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
102 			  int delta);
103 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
104 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
105 			  int delta);
106 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
107 			    struct inet6_dev *idev);
108 
109 
110 #define IGMP6_UNSOLICITED_IVAL	(10*HZ)
111 #define MLD_QRV_DEFAULT		2
112 
113 #define MLD_V1_SEEN(idev) (dev_net((idev)->dev)->ipv6.devconf_all->force_mld_version == 1 || \
114 		(idev)->cnf.force_mld_version == 1 || \
115 		((idev)->mc_v1_seen && \
116 		time_before(jiffies, (idev)->mc_v1_seen)))
117 
118 #define IPV6_MLD_MAX_MSF	64
119 
120 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
121 
122 /*
123  *	socket join on multicast group
124  */
125 
126 #define for_each_pmc_rcu(np, pmc)				\
127 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
128 	     pmc != NULL;					\
129 	     pmc = rcu_dereference(pmc->next))
130 
131 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
132 {
133 	struct net_device *dev = NULL;
134 	struct ipv6_mc_socklist *mc_lst;
135 	struct ipv6_pinfo *np = inet6_sk(sk);
136 	struct net *net = sock_net(sk);
137 	int err;
138 
139 	if (!ipv6_addr_is_multicast(addr))
140 		return -EINVAL;
141 
142 	rcu_read_lock();
143 	for_each_pmc_rcu(np, mc_lst) {
144 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
145 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
146 			rcu_read_unlock();
147 			return -EADDRINUSE;
148 		}
149 	}
150 	rcu_read_unlock();
151 
152 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
153 
154 	if (mc_lst == NULL)
155 		return -ENOMEM;
156 
157 	mc_lst->next = NULL;
158 	mc_lst->addr = *addr;
159 
160 	rcu_read_lock();
161 	if (ifindex == 0) {
162 		struct rt6_info *rt;
163 		rt = rt6_lookup(net, addr, NULL, 0, 0);
164 		if (rt) {
165 			dev = rt->dst.dev;
166 			ip6_rt_put(rt);
167 		}
168 	} else
169 		dev = dev_get_by_index_rcu(net, ifindex);
170 
171 	if (dev == NULL) {
172 		rcu_read_unlock();
173 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
174 		return -ENODEV;
175 	}
176 
177 	mc_lst->ifindex = dev->ifindex;
178 	mc_lst->sfmode = MCAST_EXCLUDE;
179 	rwlock_init(&mc_lst->sflock);
180 	mc_lst->sflist = NULL;
181 
182 	/*
183 	 *	now add/increase the group membership on the device
184 	 */
185 
186 	err = ipv6_dev_mc_inc(dev, addr);
187 
188 	if (err) {
189 		rcu_read_unlock();
190 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
191 		return err;
192 	}
193 
194 	spin_lock(&ipv6_sk_mc_lock);
195 	mc_lst->next = np->ipv6_mc_list;
196 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
197 	spin_unlock(&ipv6_sk_mc_lock);
198 
199 	rcu_read_unlock();
200 
201 	return 0;
202 }
203 
204 /*
205  *	socket leave on multicast group
206  */
207 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
208 {
209 	struct ipv6_pinfo *np = inet6_sk(sk);
210 	struct ipv6_mc_socklist *mc_lst;
211 	struct ipv6_mc_socklist __rcu **lnk;
212 	struct net *net = sock_net(sk);
213 
214 	if (!ipv6_addr_is_multicast(addr))
215 		return -EINVAL;
216 
217 	spin_lock(&ipv6_sk_mc_lock);
218 	for (lnk = &np->ipv6_mc_list;
219 	     (mc_lst = rcu_dereference_protected(*lnk,
220 			lockdep_is_held(&ipv6_sk_mc_lock))) !=NULL ;
221 	      lnk = &mc_lst->next) {
222 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
223 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
224 			struct net_device *dev;
225 
226 			*lnk = mc_lst->next;
227 			spin_unlock(&ipv6_sk_mc_lock);
228 
229 			rcu_read_lock();
230 			dev = dev_get_by_index_rcu(net, mc_lst->ifindex);
231 			if (dev != NULL) {
232 				struct inet6_dev *idev = __in6_dev_get(dev);
233 
234 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
235 				if (idev)
236 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
237 			} else
238 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
239 			rcu_read_unlock();
240 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
241 			kfree_rcu(mc_lst, rcu);
242 			return 0;
243 		}
244 	}
245 	spin_unlock(&ipv6_sk_mc_lock);
246 
247 	return -EADDRNOTAVAIL;
248 }
249 
250 /* called with rcu_read_lock() */
251 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
252 					     const struct in6_addr *group,
253 					     int ifindex)
254 {
255 	struct net_device *dev = NULL;
256 	struct inet6_dev *idev = NULL;
257 
258 	if (ifindex == 0) {
259 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, 0);
260 
261 		if (rt) {
262 			dev = rt->dst.dev;
263 			ip6_rt_put(rt);
264 		}
265 	} else
266 		dev = dev_get_by_index_rcu(net, ifindex);
267 
268 	if (!dev)
269 		return NULL;
270 	idev = __in6_dev_get(dev);
271 	if (!idev)
272 		return NULL;
273 	read_lock_bh(&idev->lock);
274 	if (idev->dead) {
275 		read_unlock_bh(&idev->lock);
276 		return NULL;
277 	}
278 	return idev;
279 }
280 
281 void ipv6_sock_mc_close(struct sock *sk)
282 {
283 	struct ipv6_pinfo *np = inet6_sk(sk);
284 	struct ipv6_mc_socklist *mc_lst;
285 	struct net *net = sock_net(sk);
286 
287 	if (!rcu_access_pointer(np->ipv6_mc_list))
288 		return;
289 
290 	spin_lock(&ipv6_sk_mc_lock);
291 	while ((mc_lst = rcu_dereference_protected(np->ipv6_mc_list,
292 				lockdep_is_held(&ipv6_sk_mc_lock))) != NULL) {
293 		struct net_device *dev;
294 
295 		np->ipv6_mc_list = mc_lst->next;
296 		spin_unlock(&ipv6_sk_mc_lock);
297 
298 		rcu_read_lock();
299 		dev = dev_get_by_index_rcu(net, mc_lst->ifindex);
300 		if (dev) {
301 			struct inet6_dev *idev = __in6_dev_get(dev);
302 
303 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
304 			if (idev)
305 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
306 		} else
307 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
308 		rcu_read_unlock();
309 
310 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
311 		kfree_rcu(mc_lst, rcu);
312 
313 		spin_lock(&ipv6_sk_mc_lock);
314 	}
315 	spin_unlock(&ipv6_sk_mc_lock);
316 }
317 
318 int ip6_mc_source(int add, int omode, struct sock *sk,
319 	struct group_source_req *pgsr)
320 {
321 	struct in6_addr *source, *group;
322 	struct ipv6_mc_socklist *pmc;
323 	struct inet6_dev *idev;
324 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
325 	struct ip6_sf_socklist *psl;
326 	struct net *net = sock_net(sk);
327 	int i, j, rv;
328 	int leavegroup = 0;
329 	int pmclocked = 0;
330 	int err;
331 
332 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
333 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
334 
335 	if (!ipv6_addr_is_multicast(group))
336 		return -EINVAL;
337 
338 	rcu_read_lock();
339 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
340 	if (!idev) {
341 		rcu_read_unlock();
342 		return -ENODEV;
343 	}
344 
345 	err = -EADDRNOTAVAIL;
346 
347 	for_each_pmc_rcu(inet6, pmc) {
348 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
349 			continue;
350 		if (ipv6_addr_equal(&pmc->addr, group))
351 			break;
352 	}
353 	if (!pmc) {		/* must have a prior join */
354 		err = -EINVAL;
355 		goto done;
356 	}
357 	/* if a source filter was set, must be the same mode as before */
358 	if (pmc->sflist) {
359 		if (pmc->sfmode != omode) {
360 			err = -EINVAL;
361 			goto done;
362 		}
363 	} else if (pmc->sfmode != omode) {
364 		/* allow mode switches for empty-set filters */
365 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
366 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
367 		pmc->sfmode = omode;
368 	}
369 
370 	write_lock(&pmc->sflock);
371 	pmclocked = 1;
372 
373 	psl = pmc->sflist;
374 	if (!add) {
375 		if (!psl)
376 			goto done;	/* err = -EADDRNOTAVAIL */
377 		rv = !0;
378 		for (i=0; i<psl->sl_count; i++) {
379 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
380 			if (rv == 0)
381 				break;
382 		}
383 		if (rv)		/* source not found */
384 			goto done;	/* err = -EADDRNOTAVAIL */
385 
386 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
387 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
388 			leavegroup = 1;
389 			goto done;
390 		}
391 
392 		/* update the interface filter */
393 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
394 
395 		for (j=i+1; j<psl->sl_count; j++)
396 			psl->sl_addr[j-1] = psl->sl_addr[j];
397 		psl->sl_count--;
398 		err = 0;
399 		goto done;
400 	}
401 	/* else, add a new source to the filter */
402 
403 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
404 		err = -ENOBUFS;
405 		goto done;
406 	}
407 	if (!psl || psl->sl_count == psl->sl_max) {
408 		struct ip6_sf_socklist *newpsl;
409 		int count = IP6_SFBLOCK;
410 
411 		if (psl)
412 			count += psl->sl_max;
413 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
414 		if (!newpsl) {
415 			err = -ENOBUFS;
416 			goto done;
417 		}
418 		newpsl->sl_max = count;
419 		newpsl->sl_count = count - IP6_SFBLOCK;
420 		if (psl) {
421 			for (i=0; i<psl->sl_count; i++)
422 				newpsl->sl_addr[i] = psl->sl_addr[i];
423 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
424 		}
425 		pmc->sflist = psl = newpsl;
426 	}
427 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
428 	for (i=0; i<psl->sl_count; i++) {
429 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
430 		if (rv == 0) /* There is an error in the address. */
431 			goto done;
432 	}
433 	for (j=psl->sl_count-1; j>=i; j--)
434 		psl->sl_addr[j+1] = psl->sl_addr[j];
435 	psl->sl_addr[i] = *source;
436 	psl->sl_count++;
437 	err = 0;
438 	/* update the interface list */
439 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
440 done:
441 	if (pmclocked)
442 		write_unlock(&pmc->sflock);
443 	read_unlock_bh(&idev->lock);
444 	rcu_read_unlock();
445 	if (leavegroup)
446 		return ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
447 	return err;
448 }
449 
450 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
451 {
452 	const struct in6_addr *group;
453 	struct ipv6_mc_socklist *pmc;
454 	struct inet6_dev *idev;
455 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
456 	struct ip6_sf_socklist *newpsl, *psl;
457 	struct net *net = sock_net(sk);
458 	int leavegroup = 0;
459 	int i, err;
460 
461 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
462 
463 	if (!ipv6_addr_is_multicast(group))
464 		return -EINVAL;
465 	if (gsf->gf_fmode != MCAST_INCLUDE &&
466 	    gsf->gf_fmode != MCAST_EXCLUDE)
467 		return -EINVAL;
468 
469 	rcu_read_lock();
470 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
471 
472 	if (!idev) {
473 		rcu_read_unlock();
474 		return -ENODEV;
475 	}
476 
477 	err = 0;
478 
479 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
480 		leavegroup = 1;
481 		goto done;
482 	}
483 
484 	for_each_pmc_rcu(inet6, pmc) {
485 		if (pmc->ifindex != gsf->gf_interface)
486 			continue;
487 		if (ipv6_addr_equal(&pmc->addr, group))
488 			break;
489 	}
490 	if (!pmc) {		/* must have a prior join */
491 		err = -EINVAL;
492 		goto done;
493 	}
494 	if (gsf->gf_numsrc) {
495 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
496 							  GFP_ATOMIC);
497 		if (!newpsl) {
498 			err = -ENOBUFS;
499 			goto done;
500 		}
501 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
502 		for (i=0; i<newpsl->sl_count; ++i) {
503 			struct sockaddr_in6 *psin6;
504 
505 			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
506 			newpsl->sl_addr[i] = psin6->sin6_addr;
507 		}
508 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
509 			newpsl->sl_count, newpsl->sl_addr, 0);
510 		if (err) {
511 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
512 			goto done;
513 		}
514 	} else {
515 		newpsl = NULL;
516 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
517 	}
518 
519 	write_lock(&pmc->sflock);
520 	psl = pmc->sflist;
521 	if (psl) {
522 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
523 			psl->sl_count, psl->sl_addr, 0);
524 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
525 	} else
526 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
527 	pmc->sflist = newpsl;
528 	pmc->sfmode = gsf->gf_fmode;
529 	write_unlock(&pmc->sflock);
530 	err = 0;
531 done:
532 	read_unlock_bh(&idev->lock);
533 	rcu_read_unlock();
534 	if (leavegroup)
535 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
536 	return err;
537 }
538 
539 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
540 	struct group_filter __user *optval, int __user *optlen)
541 {
542 	int err, i, count, copycount;
543 	const struct in6_addr *group;
544 	struct ipv6_mc_socklist *pmc;
545 	struct inet6_dev *idev;
546 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
547 	struct ip6_sf_socklist *psl;
548 	struct net *net = sock_net(sk);
549 
550 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
551 
552 	if (!ipv6_addr_is_multicast(group))
553 		return -EINVAL;
554 
555 	rcu_read_lock();
556 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
557 
558 	if (!idev) {
559 		rcu_read_unlock();
560 		return -ENODEV;
561 	}
562 
563 	err = -EADDRNOTAVAIL;
564 	/*
565 	 * changes to the ipv6_mc_list require the socket lock and
566 	 * a read lock on ip6_sk_mc_lock. We have the socket lock,
567 	 * so reading the list is safe.
568 	 */
569 
570 	for_each_pmc_rcu(inet6, pmc) {
571 		if (pmc->ifindex != gsf->gf_interface)
572 			continue;
573 		if (ipv6_addr_equal(group, &pmc->addr))
574 			break;
575 	}
576 	if (!pmc)		/* must have a prior join */
577 		goto done;
578 	gsf->gf_fmode = pmc->sfmode;
579 	psl = pmc->sflist;
580 	count = psl ? psl->sl_count : 0;
581 	read_unlock_bh(&idev->lock);
582 	rcu_read_unlock();
583 
584 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
585 	gsf->gf_numsrc = count;
586 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
587 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
588 		return -EFAULT;
589 	}
590 	/* changes to psl require the socket lock, a read lock on
591 	 * on ipv6_sk_mc_lock and a write lock on pmc->sflock. We
592 	 * have the socket lock, so reading here is safe.
593 	 */
594 	for (i=0; i<copycount; i++) {
595 		struct sockaddr_in6 *psin6;
596 		struct sockaddr_storage ss;
597 
598 		psin6 = (struct sockaddr_in6 *)&ss;
599 		memset(&ss, 0, sizeof(ss));
600 		psin6->sin6_family = AF_INET6;
601 		psin6->sin6_addr = psl->sl_addr[i];
602 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
603 			return -EFAULT;
604 	}
605 	return 0;
606 done:
607 	read_unlock_bh(&idev->lock);
608 	rcu_read_unlock();
609 	return err;
610 }
611 
612 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
613 		    const struct in6_addr *src_addr)
614 {
615 	struct ipv6_pinfo *np = inet6_sk(sk);
616 	struct ipv6_mc_socklist *mc;
617 	struct ip6_sf_socklist *psl;
618 	bool rv = true;
619 
620 	rcu_read_lock();
621 	for_each_pmc_rcu(np, mc) {
622 		if (ipv6_addr_equal(&mc->addr, mc_addr))
623 			break;
624 	}
625 	if (!mc) {
626 		rcu_read_unlock();
627 		return true;
628 	}
629 	read_lock(&mc->sflock);
630 	psl = mc->sflist;
631 	if (!psl) {
632 		rv = mc->sfmode == MCAST_EXCLUDE;
633 	} else {
634 		int i;
635 
636 		for (i=0; i<psl->sl_count; i++) {
637 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
638 				break;
639 		}
640 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
641 			rv = false;
642 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
643 			rv = false;
644 	}
645 	read_unlock(&mc->sflock);
646 	rcu_read_unlock();
647 
648 	return rv;
649 }
650 
651 static void ma_put(struct ifmcaddr6 *mc)
652 {
653 	if (atomic_dec_and_test(&mc->mca_refcnt)) {
654 		in6_dev_put(mc->idev);
655 		kfree(mc);
656 	}
657 }
658 
659 static void igmp6_group_added(struct ifmcaddr6 *mc)
660 {
661 	struct net_device *dev = mc->idev->dev;
662 	char buf[MAX_ADDR_LEN];
663 
664 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
665 	    IPV6_ADDR_SCOPE_LINKLOCAL)
666 		return;
667 
668 	spin_lock_bh(&mc->mca_lock);
669 	if (!(mc->mca_flags&MAF_LOADED)) {
670 		mc->mca_flags |= MAF_LOADED;
671 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
672 			dev_mc_add(dev, buf);
673 	}
674 	spin_unlock_bh(&mc->mca_lock);
675 
676 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
677 		return;
678 
679 	if (MLD_V1_SEEN(mc->idev)) {
680 		igmp6_join_group(mc);
681 		return;
682 	}
683 	/* else v2 */
684 
685 	mc->mca_crcount = mc->idev->mc_qrv;
686 	mld_ifc_event(mc->idev);
687 }
688 
689 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
690 {
691 	struct net_device *dev = mc->idev->dev;
692 	char buf[MAX_ADDR_LEN];
693 
694 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
695 	    IPV6_ADDR_SCOPE_LINKLOCAL)
696 		return;
697 
698 	spin_lock_bh(&mc->mca_lock);
699 	if (mc->mca_flags&MAF_LOADED) {
700 		mc->mca_flags &= ~MAF_LOADED;
701 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
702 			dev_mc_del(dev, buf);
703 	}
704 
705 	if (mc->mca_flags & MAF_NOREPORT)
706 		goto done;
707 	spin_unlock_bh(&mc->mca_lock);
708 
709 	if (!mc->idev->dead)
710 		igmp6_leave_group(mc);
711 
712 	spin_lock_bh(&mc->mca_lock);
713 	if (del_timer(&mc->mca_timer))
714 		atomic_dec(&mc->mca_refcnt);
715 done:
716 	ip6_mc_clear_src(mc);
717 	spin_unlock_bh(&mc->mca_lock);
718 }
719 
720 /*
721  * deleted ifmcaddr6 manipulation
722  */
723 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
724 {
725 	struct ifmcaddr6 *pmc;
726 
727 	/* this is an "ifmcaddr6" for convenience; only the fields below
728 	 * are actually used. In particular, the refcnt and users are not
729 	 * used for management of the delete list. Using the same structure
730 	 * for deleted items allows change reports to use common code with
731 	 * non-deleted or query-response MCA's.
732 	 */
733 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
734 	if (!pmc)
735 		return;
736 
737 	spin_lock_bh(&im->mca_lock);
738 	spin_lock_init(&pmc->mca_lock);
739 	pmc->idev = im->idev;
740 	in6_dev_hold(idev);
741 	pmc->mca_addr = im->mca_addr;
742 	pmc->mca_crcount = idev->mc_qrv;
743 	pmc->mca_sfmode = im->mca_sfmode;
744 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
745 		struct ip6_sf_list *psf;
746 
747 		pmc->mca_tomb = im->mca_tomb;
748 		pmc->mca_sources = im->mca_sources;
749 		im->mca_tomb = im->mca_sources = NULL;
750 		for (psf=pmc->mca_sources; psf; psf=psf->sf_next)
751 			psf->sf_crcount = pmc->mca_crcount;
752 	}
753 	spin_unlock_bh(&im->mca_lock);
754 
755 	spin_lock_bh(&idev->mc_lock);
756 	pmc->next = idev->mc_tomb;
757 	idev->mc_tomb = pmc;
758 	spin_unlock_bh(&idev->mc_lock);
759 }
760 
761 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *pmca)
762 {
763 	struct ifmcaddr6 *pmc, *pmc_prev;
764 	struct ip6_sf_list *psf, *psf_next;
765 
766 	spin_lock_bh(&idev->mc_lock);
767 	pmc_prev = NULL;
768 	for (pmc=idev->mc_tomb; pmc; pmc=pmc->next) {
769 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
770 			break;
771 		pmc_prev = pmc;
772 	}
773 	if (pmc) {
774 		if (pmc_prev)
775 			pmc_prev->next = pmc->next;
776 		else
777 			idev->mc_tomb = pmc->next;
778 	}
779 	spin_unlock_bh(&idev->mc_lock);
780 
781 	if (pmc) {
782 		for (psf=pmc->mca_tomb; psf; psf=psf_next) {
783 			psf_next = psf->sf_next;
784 			kfree(psf);
785 		}
786 		in6_dev_put(pmc->idev);
787 		kfree(pmc);
788 	}
789 }
790 
791 static void mld_clear_delrec(struct inet6_dev *idev)
792 {
793 	struct ifmcaddr6 *pmc, *nextpmc;
794 
795 	spin_lock_bh(&idev->mc_lock);
796 	pmc = idev->mc_tomb;
797 	idev->mc_tomb = NULL;
798 	spin_unlock_bh(&idev->mc_lock);
799 
800 	for (; pmc; pmc = nextpmc) {
801 		nextpmc = pmc->next;
802 		ip6_mc_clear_src(pmc);
803 		in6_dev_put(pmc->idev);
804 		kfree(pmc);
805 	}
806 
807 	/* clear dead sources, too */
808 	read_lock_bh(&idev->lock);
809 	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
810 		struct ip6_sf_list *psf, *psf_next;
811 
812 		spin_lock_bh(&pmc->mca_lock);
813 		psf = pmc->mca_tomb;
814 		pmc->mca_tomb = NULL;
815 		spin_unlock_bh(&pmc->mca_lock);
816 		for (; psf; psf=psf_next) {
817 			psf_next = psf->sf_next;
818 			kfree(psf);
819 		}
820 	}
821 	read_unlock_bh(&idev->lock);
822 }
823 
824 
825 /*
826  *	device multicast group inc (add if not found)
827  */
828 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
829 {
830 	struct ifmcaddr6 *mc;
831 	struct inet6_dev *idev;
832 
833 	/* we need to take a reference on idev */
834 	idev = in6_dev_get(dev);
835 
836 	if (idev == NULL)
837 		return -EINVAL;
838 
839 	write_lock_bh(&idev->lock);
840 	if (idev->dead) {
841 		write_unlock_bh(&idev->lock);
842 		in6_dev_put(idev);
843 		return -ENODEV;
844 	}
845 
846 	for (mc = idev->mc_list; mc; mc = mc->next) {
847 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
848 			mc->mca_users++;
849 			write_unlock_bh(&idev->lock);
850 			ip6_mc_add_src(idev, &mc->mca_addr, MCAST_EXCLUDE, 0,
851 				NULL, 0);
852 			in6_dev_put(idev);
853 			return 0;
854 		}
855 	}
856 
857 	/*
858 	 *	not found: create a new one.
859 	 */
860 
861 	mc = kzalloc(sizeof(struct ifmcaddr6), GFP_ATOMIC);
862 
863 	if (mc == NULL) {
864 		write_unlock_bh(&idev->lock);
865 		in6_dev_put(idev);
866 		return -ENOMEM;
867 	}
868 
869 	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);
870 
871 	mc->mca_addr = *addr;
872 	mc->idev = idev; /* (reference taken) */
873 	mc->mca_users = 1;
874 	/* mca_stamp should be updated upon changes */
875 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
876 	atomic_set(&mc->mca_refcnt, 2);
877 	spin_lock_init(&mc->mca_lock);
878 
879 	/* initial mode is (EX, empty) */
880 	mc->mca_sfmode = MCAST_EXCLUDE;
881 	mc->mca_sfcount[MCAST_EXCLUDE] = 1;
882 
883 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
884 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
885 		mc->mca_flags |= MAF_NOREPORT;
886 
887 	mc->next = idev->mc_list;
888 	idev->mc_list = mc;
889 	write_unlock_bh(&idev->lock);
890 
891 	mld_del_delrec(idev, &mc->mca_addr);
892 	igmp6_group_added(mc);
893 	ma_put(mc);
894 	return 0;
895 }
896 
897 /*
898  *	device multicast group del
899  */
900 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
901 {
902 	struct ifmcaddr6 *ma, **map;
903 
904 	write_lock_bh(&idev->lock);
905 	for (map = &idev->mc_list; (ma=*map) != NULL; map = &ma->next) {
906 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
907 			if (--ma->mca_users == 0) {
908 				*map = ma->next;
909 				write_unlock_bh(&idev->lock);
910 
911 				igmp6_group_dropped(ma);
912 
913 				ma_put(ma);
914 				return 0;
915 			}
916 			write_unlock_bh(&idev->lock);
917 			return 0;
918 		}
919 	}
920 	write_unlock_bh(&idev->lock);
921 
922 	return -ENOENT;
923 }
924 
925 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
926 {
927 	struct inet6_dev *idev;
928 	int err;
929 
930 	rcu_read_lock();
931 
932 	idev = __in6_dev_get(dev);
933 	if (!idev)
934 		err = -ENODEV;
935 	else
936 		err = __ipv6_dev_mc_dec(idev, addr);
937 
938 	rcu_read_unlock();
939 	return err;
940 }
941 
942 /*
943  *	check if the interface/address pair is valid
944  */
945 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
946 			 const struct in6_addr *src_addr)
947 {
948 	struct inet6_dev *idev;
949 	struct ifmcaddr6 *mc;
950 	bool rv = false;
951 
952 	rcu_read_lock();
953 	idev = __in6_dev_get(dev);
954 	if (idev) {
955 		read_lock_bh(&idev->lock);
956 		for (mc = idev->mc_list; mc; mc=mc->next) {
957 			if (ipv6_addr_equal(&mc->mca_addr, group))
958 				break;
959 		}
960 		if (mc) {
961 			if (src_addr && !ipv6_addr_any(src_addr)) {
962 				struct ip6_sf_list *psf;
963 
964 				spin_lock_bh(&mc->mca_lock);
965 				for (psf=mc->mca_sources;psf;psf=psf->sf_next) {
966 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
967 						break;
968 				}
969 				if (psf)
970 					rv = psf->sf_count[MCAST_INCLUDE] ||
971 						psf->sf_count[MCAST_EXCLUDE] !=
972 						mc->mca_sfcount[MCAST_EXCLUDE];
973 				else
974 					rv = mc->mca_sfcount[MCAST_EXCLUDE] !=0;
975 				spin_unlock_bh(&mc->mca_lock);
976 			} else
977 				rv = true; /* don't filter unspecified source */
978 		}
979 		read_unlock_bh(&idev->lock);
980 	}
981 	rcu_read_unlock();
982 	return rv;
983 }
984 
985 static void mld_gq_start_timer(struct inet6_dev *idev)
986 {
987 	int tv = net_random() % idev->mc_maxdelay;
988 
989 	idev->mc_gq_running = 1;
990 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
991 		in6_dev_hold(idev);
992 }
993 
994 static void mld_ifc_start_timer(struct inet6_dev *idev, int delay)
995 {
996 	int tv = net_random() % delay;
997 
998 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
999 		in6_dev_hold(idev);
1000 }
1001 
1002 static void mld_dad_start_timer(struct inet6_dev *idev, int delay)
1003 {
1004 	int tv = net_random() % delay;
1005 
1006 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1007 		in6_dev_hold(idev);
1008 }
1009 
1010 /*
1011  *	IGMP handling (alias multicast ICMPv6 messages)
1012  */
1013 
1014 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1015 {
1016 	unsigned long delay = resptime;
1017 
1018 	/* Do not start timer for these addresses */
1019 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1020 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1021 		return;
1022 
1023 	if (del_timer(&ma->mca_timer)) {
1024 		atomic_dec(&ma->mca_refcnt);
1025 		delay = ma->mca_timer.expires - jiffies;
1026 	}
1027 
1028 	if (delay >= resptime) {
1029 		if (resptime)
1030 			delay = net_random() % resptime;
1031 		else
1032 			delay = 1;
1033 	}
1034 	ma->mca_timer.expires = jiffies + delay;
1035 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1036 		atomic_inc(&ma->mca_refcnt);
1037 	ma->mca_flags |= MAF_TIMER_RUNNING;
1038 }
1039 
1040 /* mark EXCLUDE-mode sources */
1041 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1042 			     const struct in6_addr *srcs)
1043 {
1044 	struct ip6_sf_list *psf;
1045 	int i, scount;
1046 
1047 	scount = 0;
1048 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
1049 		if (scount == nsrcs)
1050 			break;
1051 		for (i=0; i<nsrcs; i++) {
1052 			/* skip inactive filters */
1053 			if (psf->sf_count[MCAST_INCLUDE] ||
1054 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1055 			    psf->sf_count[MCAST_EXCLUDE])
1056 				break;
1057 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1058 				scount++;
1059 				break;
1060 			}
1061 		}
1062 	}
1063 	pmc->mca_flags &= ~MAF_GSQUERY;
1064 	if (scount == nsrcs)	/* all sources excluded */
1065 		return false;
1066 	return true;
1067 }
1068 
1069 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1070 			    const struct in6_addr *srcs)
1071 {
1072 	struct ip6_sf_list *psf;
1073 	int i, scount;
1074 
1075 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1076 		return mld_xmarksources(pmc, nsrcs, srcs);
1077 
1078 	/* mark INCLUDE-mode sources */
1079 
1080 	scount = 0;
1081 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
1082 		if (scount == nsrcs)
1083 			break;
1084 		for (i=0; i<nsrcs; i++) {
1085 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1086 				psf->sf_gsresp = 1;
1087 				scount++;
1088 				break;
1089 			}
1090 		}
1091 	}
1092 	if (!scount) {
1093 		pmc->mca_flags &= ~MAF_GSQUERY;
1094 		return false;
1095 	}
1096 	pmc->mca_flags |= MAF_GSQUERY;
1097 	return true;
1098 }
1099 
1100 /* called with rcu_read_lock() */
1101 int igmp6_event_query(struct sk_buff *skb)
1102 {
1103 	struct mld2_query *mlh2 = NULL;
1104 	struct ifmcaddr6 *ma;
1105 	const struct in6_addr *group;
1106 	unsigned long max_delay;
1107 	struct inet6_dev *idev;
1108 	struct mld_msg *mld;
1109 	int group_type;
1110 	int mark = 0;
1111 	int len;
1112 
1113 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1114 		return -EINVAL;
1115 
1116 	/* compute payload length excluding extension headers */
1117 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1118 	len -= skb_network_header_len(skb);
1119 
1120 	/* Drop queries with not link local source */
1121 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL))
1122 		return -EINVAL;
1123 
1124 	idev = __in6_dev_get(skb->dev);
1125 
1126 	if (idev == NULL)
1127 		return 0;
1128 
1129 	mld = (struct mld_msg *)icmp6_hdr(skb);
1130 	group = &mld->mld_mca;
1131 	group_type = ipv6_addr_type(group);
1132 
1133 	if (group_type != IPV6_ADDR_ANY &&
1134 	    !(group_type&IPV6_ADDR_MULTICAST))
1135 		return -EINVAL;
1136 
1137 	if (len == 24) {
1138 		int switchback;
1139 		/* MLDv1 router present */
1140 
1141 		/* Translate milliseconds to jiffies */
1142 		max_delay = (ntohs(mld->mld_maxdelay)*HZ)/1000;
1143 
1144 		switchback = (idev->mc_qrv + 1) * max_delay;
1145 		idev->mc_v1_seen = jiffies + switchback;
1146 
1147 		/* cancel the interface change timer */
1148 		idev->mc_ifc_count = 0;
1149 		if (del_timer(&idev->mc_ifc_timer))
1150 			__in6_dev_put(idev);
1151 		/* clear deleted report items */
1152 		mld_clear_delrec(idev);
1153 	} else if (len >= 28) {
1154 		int srcs_offset = sizeof(struct mld2_query) -
1155 				  sizeof(struct icmp6hdr);
1156 		if (!pskb_may_pull(skb, srcs_offset))
1157 			return -EINVAL;
1158 
1159 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1160 		max_delay = (MLDV2_MRC(ntohs(mlh2->mld2q_mrc))*HZ)/1000;
1161 		if (!max_delay)
1162 			max_delay = 1;
1163 		idev->mc_maxdelay = max_delay;
1164 		if (mlh2->mld2q_qrv)
1165 			idev->mc_qrv = mlh2->mld2q_qrv;
1166 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1167 			if (mlh2->mld2q_nsrcs)
1168 				return -EINVAL; /* no sources allowed */
1169 
1170 			mld_gq_start_timer(idev);
1171 			return 0;
1172 		}
1173 		/* mark sources to include, if group & source-specific */
1174 		if (mlh2->mld2q_nsrcs != 0) {
1175 			if (!pskb_may_pull(skb, srcs_offset +
1176 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1177 				return -EINVAL;
1178 
1179 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1180 			mark = 1;
1181 		}
1182 	} else
1183 		return -EINVAL;
1184 
1185 	read_lock_bh(&idev->lock);
1186 	if (group_type == IPV6_ADDR_ANY) {
1187 		for (ma = idev->mc_list; ma; ma=ma->next) {
1188 			spin_lock_bh(&ma->mca_lock);
1189 			igmp6_group_queried(ma, max_delay);
1190 			spin_unlock_bh(&ma->mca_lock);
1191 		}
1192 	} else {
1193 		for (ma = idev->mc_list; ma; ma=ma->next) {
1194 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1195 				continue;
1196 			spin_lock_bh(&ma->mca_lock);
1197 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1198 				/* gsquery <- gsquery && mark */
1199 				if (!mark)
1200 					ma->mca_flags &= ~MAF_GSQUERY;
1201 			} else {
1202 				/* gsquery <- mark */
1203 				if (mark)
1204 					ma->mca_flags |= MAF_GSQUERY;
1205 				else
1206 					ma->mca_flags &= ~MAF_GSQUERY;
1207 			}
1208 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1209 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1210 				igmp6_group_queried(ma, max_delay);
1211 			spin_unlock_bh(&ma->mca_lock);
1212 			break;
1213 		}
1214 	}
1215 	read_unlock_bh(&idev->lock);
1216 
1217 	return 0;
1218 }
1219 
1220 /* called with rcu_read_lock() */
1221 int igmp6_event_report(struct sk_buff *skb)
1222 {
1223 	struct ifmcaddr6 *ma;
1224 	struct inet6_dev *idev;
1225 	struct mld_msg *mld;
1226 	int addr_type;
1227 
1228 	/* Our own report looped back. Ignore it. */
1229 	if (skb->pkt_type == PACKET_LOOPBACK)
1230 		return 0;
1231 
1232 	/* send our report if the MC router may not have heard this report */
1233 	if (skb->pkt_type != PACKET_MULTICAST &&
1234 	    skb->pkt_type != PACKET_BROADCAST)
1235 		return 0;
1236 
1237 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1238 		return -EINVAL;
1239 
1240 	mld = (struct mld_msg *)icmp6_hdr(skb);
1241 
1242 	/* Drop reports with not link local source */
1243 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1244 	if (addr_type != IPV6_ADDR_ANY &&
1245 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1246 		return -EINVAL;
1247 
1248 	idev = __in6_dev_get(skb->dev);
1249 	if (idev == NULL)
1250 		return -ENODEV;
1251 
1252 	/*
1253 	 *	Cancel the timer for this group
1254 	 */
1255 
1256 	read_lock_bh(&idev->lock);
1257 	for (ma = idev->mc_list; ma; ma=ma->next) {
1258 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1259 			spin_lock(&ma->mca_lock);
1260 			if (del_timer(&ma->mca_timer))
1261 				atomic_dec(&ma->mca_refcnt);
1262 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1263 			spin_unlock(&ma->mca_lock);
1264 			break;
1265 		}
1266 	}
1267 	read_unlock_bh(&idev->lock);
1268 	return 0;
1269 }
1270 
1271 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1272 		  int gdeleted, int sdeleted)
1273 {
1274 	switch (type) {
1275 	case MLD2_MODE_IS_INCLUDE:
1276 	case MLD2_MODE_IS_EXCLUDE:
1277 		if (gdeleted || sdeleted)
1278 			return false;
1279 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1280 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1281 				return true;
1282 			/* don't include if this source is excluded
1283 			 * in all filters
1284 			 */
1285 			if (psf->sf_count[MCAST_INCLUDE])
1286 				return type == MLD2_MODE_IS_INCLUDE;
1287 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1288 				psf->sf_count[MCAST_EXCLUDE];
1289 		}
1290 		return false;
1291 	case MLD2_CHANGE_TO_INCLUDE:
1292 		if (gdeleted || sdeleted)
1293 			return false;
1294 		return psf->sf_count[MCAST_INCLUDE] != 0;
1295 	case MLD2_CHANGE_TO_EXCLUDE:
1296 		if (gdeleted || sdeleted)
1297 			return false;
1298 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1299 		    psf->sf_count[MCAST_INCLUDE])
1300 			return false;
1301 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1302 			psf->sf_count[MCAST_EXCLUDE];
1303 	case MLD2_ALLOW_NEW_SOURCES:
1304 		if (gdeleted || !psf->sf_crcount)
1305 			return false;
1306 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1307 	case MLD2_BLOCK_OLD_SOURCES:
1308 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1309 			return gdeleted || (psf->sf_crcount && sdeleted);
1310 		return psf->sf_crcount && !gdeleted && !sdeleted;
1311 	}
1312 	return false;
1313 }
1314 
1315 static int
1316 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1317 {
1318 	struct ip6_sf_list *psf;
1319 	int scount = 0;
1320 
1321 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
1322 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1323 			continue;
1324 		scount++;
1325 	}
1326 	return scount;
1327 }
1328 
1329 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1330 		       struct net_device *dev,
1331 		       const struct in6_addr *saddr,
1332 		       const struct in6_addr *daddr,
1333 		       int proto, int len)
1334 {
1335 	struct ipv6hdr *hdr;
1336 
1337 	skb->protocol = htons(ETH_P_IPV6);
1338 	skb->dev = dev;
1339 
1340 	skb_reset_network_header(skb);
1341 	skb_put(skb, sizeof(struct ipv6hdr));
1342 	hdr = ipv6_hdr(skb);
1343 
1344 	ip6_flow_hdr(hdr, 0, 0);
1345 
1346 	hdr->payload_len = htons(len);
1347 	hdr->nexthdr = proto;
1348 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1349 
1350 	hdr->saddr = *saddr;
1351 	hdr->daddr = *daddr;
1352 }
1353 
1354 static struct sk_buff *mld_newpack(struct inet6_dev *idev, int size)
1355 {
1356 	struct net_device *dev = idev->dev;
1357 	struct net *net = dev_net(dev);
1358 	struct sock *sk = net->ipv6.igmp_sk;
1359 	struct sk_buff *skb;
1360 	struct mld2_report *pmr;
1361 	struct in6_addr addr_buf;
1362 	const struct in6_addr *saddr;
1363 	int hlen = LL_RESERVED_SPACE(dev);
1364 	int tlen = dev->needed_tailroom;
1365 	int err;
1366 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1367 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1368 		     IPV6_TLV_PADN, 0 };
1369 
1370 	/* we assume size > sizeof(ra) here */
1371 	size += hlen + tlen;
1372 	/* limit our allocations to order-0 page */
1373 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1374 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1375 
1376 	if (!skb)
1377 		return NULL;
1378 
1379 	skb_reserve(skb, hlen);
1380 
1381 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1382 		/* <draft-ietf-magma-mld-source-05.txt>:
1383 		 * use unspecified address as the source address
1384 		 * when a valid link-local address is not available.
1385 		 */
1386 		saddr = &in6addr_any;
1387 	} else
1388 		saddr = &addr_buf;
1389 
1390 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1391 
1392 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
1393 
1394 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1395 	skb_put(skb, sizeof(*pmr));
1396 	pmr = (struct mld2_report *)skb_transport_header(skb);
1397 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1398 	pmr->mld2r_resv1 = 0;
1399 	pmr->mld2r_cksum = 0;
1400 	pmr->mld2r_resv2 = 0;
1401 	pmr->mld2r_ngrec = 0;
1402 	return skb;
1403 }
1404 
1405 static void mld_sendpack(struct sk_buff *skb)
1406 {
1407 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1408 	struct mld2_report *pmr =
1409 			      (struct mld2_report *)skb_transport_header(skb);
1410 	int payload_len, mldlen;
1411 	struct inet6_dev *idev;
1412 	struct net *net = dev_net(skb->dev);
1413 	int err;
1414 	struct flowi6 fl6;
1415 	struct dst_entry *dst;
1416 
1417 	rcu_read_lock();
1418 	idev = __in6_dev_get(skb->dev);
1419 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1420 
1421 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1422 		sizeof(*pip6);
1423 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1424 	pip6->payload_len = htons(payload_len);
1425 
1426 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1427 					   IPPROTO_ICMPV6,
1428 					   csum_partial(skb_transport_header(skb),
1429 							mldlen, 0));
1430 
1431 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1432 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1433 			 skb->dev->ifindex);
1434 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1435 
1436 	err = 0;
1437 	if (IS_ERR(dst)) {
1438 		err = PTR_ERR(dst);
1439 		dst = NULL;
1440 	}
1441 	skb_dst_set(skb, dst);
1442 	if (err)
1443 		goto err_out;
1444 
1445 	payload_len = skb->len;
1446 
1447 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,
1448 		      dst_output);
1449 out:
1450 	if (!err) {
1451 		ICMP6MSGOUT_INC_STATS_BH(net, idev, ICMPV6_MLD2_REPORT);
1452 		ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
1453 		IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);
1454 	} else
1455 		IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTDISCARDS);
1456 
1457 	rcu_read_unlock();
1458 	return;
1459 
1460 err_out:
1461 	kfree_skb(skb);
1462 	goto out;
1463 }
1464 
1465 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1466 {
1467 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1468 }
1469 
1470 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1471 	int type, struct mld2_grec **ppgr)
1472 {
1473 	struct net_device *dev = pmc->idev->dev;
1474 	struct mld2_report *pmr;
1475 	struct mld2_grec *pgr;
1476 
1477 	if (!skb)
1478 		skb = mld_newpack(pmc->idev, dev->mtu);
1479 	if (!skb)
1480 		return NULL;
1481 	pgr = (struct mld2_grec *)skb_put(skb, sizeof(struct mld2_grec));
1482 	pgr->grec_type = type;
1483 	pgr->grec_auxwords = 0;
1484 	pgr->grec_nsrcs = 0;
1485 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1486 	pmr = (struct mld2_report *)skb_transport_header(skb);
1487 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1488 	*ppgr = pgr;
1489 	return skb;
1490 }
1491 
1492 #define AVAILABLE(skb) ((skb) ? ((skb)->dev ? (skb)->dev->mtu - (skb)->len : \
1493 	skb_tailroom(skb)) : 0)
1494 
1495 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1496 	int type, int gdeleted, int sdeleted)
1497 {
1498 	struct inet6_dev *idev = pmc->idev;
1499 	struct net_device *dev = idev->dev;
1500 	struct mld2_report *pmr;
1501 	struct mld2_grec *pgr = NULL;
1502 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1503 	int scount, stotal, first, isquery, truncate;
1504 
1505 	if (pmc->mca_flags & MAF_NOREPORT)
1506 		return skb;
1507 
1508 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1509 		  type == MLD2_MODE_IS_EXCLUDE;
1510 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1511 		    type == MLD2_CHANGE_TO_EXCLUDE;
1512 
1513 	stotal = scount = 0;
1514 
1515 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1516 
1517 	if (!*psf_list)
1518 		goto empty_source;
1519 
1520 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1521 
1522 	/* EX and TO_EX get a fresh packet, if needed */
1523 	if (truncate) {
1524 		if (pmr && pmr->mld2r_ngrec &&
1525 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1526 			if (skb)
1527 				mld_sendpack(skb);
1528 			skb = mld_newpack(idev, dev->mtu);
1529 		}
1530 	}
1531 	first = 1;
1532 	psf_prev = NULL;
1533 	for (psf=*psf_list; psf; psf=psf_next) {
1534 		struct in6_addr *psrc;
1535 
1536 		psf_next = psf->sf_next;
1537 
1538 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
1539 			psf_prev = psf;
1540 			continue;
1541 		}
1542 
1543 		/* clear marks on query responses */
1544 		if (isquery)
1545 			psf->sf_gsresp = 0;
1546 
1547 		if (AVAILABLE(skb) < sizeof(*psrc) +
1548 		    first*sizeof(struct mld2_grec)) {
1549 			if (truncate && !first)
1550 				break;	 /* truncate these */
1551 			if (pgr)
1552 				pgr->grec_nsrcs = htons(scount);
1553 			if (skb)
1554 				mld_sendpack(skb);
1555 			skb = mld_newpack(idev, dev->mtu);
1556 			first = 1;
1557 			scount = 0;
1558 		}
1559 		if (first) {
1560 			skb = add_grhead(skb, pmc, type, &pgr);
1561 			first = 0;
1562 		}
1563 		if (!skb)
1564 			return NULL;
1565 		psrc = (struct in6_addr *)skb_put(skb, sizeof(*psrc));
1566 		*psrc = psf->sf_addr;
1567 		scount++; stotal++;
1568 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1569 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1570 			psf->sf_crcount--;
1571 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1572 				if (psf_prev)
1573 					psf_prev->sf_next = psf->sf_next;
1574 				else
1575 					*psf_list = psf->sf_next;
1576 				kfree(psf);
1577 				continue;
1578 			}
1579 		}
1580 		psf_prev = psf;
1581 	}
1582 
1583 empty_source:
1584 	if (!stotal) {
1585 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1586 		    type == MLD2_BLOCK_OLD_SOURCES)
1587 			return skb;
1588 		if (pmc->mca_crcount || isquery) {
1589 			/* make sure we have room for group header */
1590 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1591 				mld_sendpack(skb);
1592 				skb = NULL; /* add_grhead will get a new one */
1593 			}
1594 			skb = add_grhead(skb, pmc, type, &pgr);
1595 		}
1596 	}
1597 	if (pgr)
1598 		pgr->grec_nsrcs = htons(scount);
1599 
1600 	if (isquery)
1601 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1602 	return skb;
1603 }
1604 
1605 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1606 {
1607 	struct sk_buff *skb = NULL;
1608 	int type;
1609 
1610 	read_lock_bh(&idev->lock);
1611 	if (!pmc) {
1612 		for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
1613 			if (pmc->mca_flags & MAF_NOREPORT)
1614 				continue;
1615 			spin_lock_bh(&pmc->mca_lock);
1616 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1617 				type = MLD2_MODE_IS_EXCLUDE;
1618 			else
1619 				type = MLD2_MODE_IS_INCLUDE;
1620 			skb = add_grec(skb, pmc, type, 0, 0);
1621 			spin_unlock_bh(&pmc->mca_lock);
1622 		}
1623 	} else {
1624 		spin_lock_bh(&pmc->mca_lock);
1625 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1626 			type = MLD2_MODE_IS_EXCLUDE;
1627 		else
1628 			type = MLD2_MODE_IS_INCLUDE;
1629 		skb = add_grec(skb, pmc, type, 0, 0);
1630 		spin_unlock_bh(&pmc->mca_lock);
1631 	}
1632 	read_unlock_bh(&idev->lock);
1633 	if (skb)
1634 		mld_sendpack(skb);
1635 }
1636 
1637 /*
1638  * remove zero-count source records from a source filter list
1639  */
1640 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1641 {
1642 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1643 
1644 	psf_prev = NULL;
1645 	for (psf=*ppsf; psf; psf = psf_next) {
1646 		psf_next = psf->sf_next;
1647 		if (psf->sf_crcount == 0) {
1648 			if (psf_prev)
1649 				psf_prev->sf_next = psf->sf_next;
1650 			else
1651 				*ppsf = psf->sf_next;
1652 			kfree(psf);
1653 		} else
1654 			psf_prev = psf;
1655 	}
1656 }
1657 
1658 static void mld_send_cr(struct inet6_dev *idev)
1659 {
1660 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1661 	struct sk_buff *skb = NULL;
1662 	int type, dtype;
1663 
1664 	read_lock_bh(&idev->lock);
1665 	spin_lock(&idev->mc_lock);
1666 
1667 	/* deleted MCA's */
1668 	pmc_prev = NULL;
1669 	for (pmc=idev->mc_tomb; pmc; pmc=pmc_next) {
1670 		pmc_next = pmc->next;
1671 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1672 			type = MLD2_BLOCK_OLD_SOURCES;
1673 			dtype = MLD2_BLOCK_OLD_SOURCES;
1674 			skb = add_grec(skb, pmc, type, 1, 0);
1675 			skb = add_grec(skb, pmc, dtype, 1, 1);
1676 		}
1677 		if (pmc->mca_crcount) {
1678 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1679 				type = MLD2_CHANGE_TO_INCLUDE;
1680 				skb = add_grec(skb, pmc, type, 1, 0);
1681 			}
1682 			pmc->mca_crcount--;
1683 			if (pmc->mca_crcount == 0) {
1684 				mld_clear_zeros(&pmc->mca_tomb);
1685 				mld_clear_zeros(&pmc->mca_sources);
1686 			}
1687 		}
1688 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1689 		    !pmc->mca_sources) {
1690 			if (pmc_prev)
1691 				pmc_prev->next = pmc_next;
1692 			else
1693 				idev->mc_tomb = pmc_next;
1694 			in6_dev_put(pmc->idev);
1695 			kfree(pmc);
1696 		} else
1697 			pmc_prev = pmc;
1698 	}
1699 	spin_unlock(&idev->mc_lock);
1700 
1701 	/* change recs */
1702 	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
1703 		spin_lock_bh(&pmc->mca_lock);
1704 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1705 			type = MLD2_BLOCK_OLD_SOURCES;
1706 			dtype = MLD2_ALLOW_NEW_SOURCES;
1707 		} else {
1708 			type = MLD2_ALLOW_NEW_SOURCES;
1709 			dtype = MLD2_BLOCK_OLD_SOURCES;
1710 		}
1711 		skb = add_grec(skb, pmc, type, 0, 0);
1712 		skb = add_grec(skb, pmc, dtype, 0, 1);	/* deleted sources */
1713 
1714 		/* filter mode changes */
1715 		if (pmc->mca_crcount) {
1716 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1717 				type = MLD2_CHANGE_TO_EXCLUDE;
1718 			else
1719 				type = MLD2_CHANGE_TO_INCLUDE;
1720 			skb = add_grec(skb, pmc, type, 0, 0);
1721 			pmc->mca_crcount--;
1722 		}
1723 		spin_unlock_bh(&pmc->mca_lock);
1724 	}
1725 	read_unlock_bh(&idev->lock);
1726 	if (!skb)
1727 		return;
1728 	(void) mld_sendpack(skb);
1729 }
1730 
1731 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1732 {
1733 	struct net *net = dev_net(dev);
1734 	struct sock *sk = net->ipv6.igmp_sk;
1735 	struct inet6_dev *idev;
1736 	struct sk_buff *skb;
1737 	struct mld_msg *hdr;
1738 	const struct in6_addr *snd_addr, *saddr;
1739 	struct in6_addr addr_buf;
1740 	int hlen = LL_RESERVED_SPACE(dev);
1741 	int tlen = dev->needed_tailroom;
1742 	int err, len, payload_len, full_len;
1743 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1744 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1745 		     IPV6_TLV_PADN, 0 };
1746 	struct flowi6 fl6;
1747 	struct dst_entry *dst;
1748 
1749 	if (type == ICMPV6_MGM_REDUCTION)
1750 		snd_addr = &in6addr_linklocal_allrouters;
1751 	else
1752 		snd_addr = addr;
1753 
1754 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
1755 	payload_len = len + sizeof(ra);
1756 	full_len = sizeof(struct ipv6hdr) + payload_len;
1757 
1758 	rcu_read_lock();
1759 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
1760 		      IPSTATS_MIB_OUT, full_len);
1761 	rcu_read_unlock();
1762 
1763 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
1764 
1765 	if (skb == NULL) {
1766 		rcu_read_lock();
1767 		IP6_INC_STATS(net, __in6_dev_get(dev),
1768 			      IPSTATS_MIB_OUTDISCARDS);
1769 		rcu_read_unlock();
1770 		return;
1771 	}
1772 
1773 	skb_reserve(skb, hlen);
1774 
1775 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1776 		/* <draft-ietf-magma-mld-source-05.txt>:
1777 		 * use unspecified address as the source address
1778 		 * when a valid link-local address is not available.
1779 		 */
1780 		saddr = &in6addr_any;
1781 	} else
1782 		saddr = &addr_buf;
1783 
1784 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
1785 
1786 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
1787 
1788 	hdr = (struct mld_msg *) skb_put(skb, sizeof(struct mld_msg));
1789 	memset(hdr, 0, sizeof(struct mld_msg));
1790 	hdr->mld_type = type;
1791 	hdr->mld_mca = *addr;
1792 
1793 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
1794 					 IPPROTO_ICMPV6,
1795 					 csum_partial(hdr, len, 0));
1796 
1797 	rcu_read_lock();
1798 	idev = __in6_dev_get(skb->dev);
1799 
1800 	icmpv6_flow_init(sk, &fl6, type,
1801 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1802 			 skb->dev->ifindex);
1803 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1804 	if (IS_ERR(dst)) {
1805 		err = PTR_ERR(dst);
1806 		goto err_out;
1807 	}
1808 
1809 	skb_dst_set(skb, dst);
1810 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,
1811 		      dst_output);
1812 out:
1813 	if (!err) {
1814 		ICMP6MSGOUT_INC_STATS(net, idev, type);
1815 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1816 		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, full_len);
1817 	} else
1818 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1819 
1820 	rcu_read_unlock();
1821 	return;
1822 
1823 err_out:
1824 	kfree_skb(skb);
1825 	goto out;
1826 }
1827 
1828 static void mld_resend_report(struct inet6_dev *idev)
1829 {
1830 	if (MLD_V1_SEEN(idev)) {
1831 		struct ifmcaddr6 *mcaddr;
1832 		read_lock_bh(&idev->lock);
1833 		for (mcaddr = idev->mc_list; mcaddr; mcaddr = mcaddr->next) {
1834 			if (!(mcaddr->mca_flags & MAF_NOREPORT))
1835 				igmp6_send(&mcaddr->mca_addr, idev->dev,
1836 					   ICMPV6_MGM_REPORT);
1837 		}
1838 		read_unlock_bh(&idev->lock);
1839 	} else {
1840 		mld_send_report(idev, NULL);
1841 	}
1842 }
1843 
1844 void ipv6_mc_dad_complete(struct inet6_dev *idev)
1845 {
1846 	idev->mc_dad_count = idev->mc_qrv;
1847 	if (idev->mc_dad_count) {
1848 		mld_resend_report(idev);
1849 		idev->mc_dad_count--;
1850 		if (idev->mc_dad_count)
1851 			mld_dad_start_timer(idev, idev->mc_maxdelay);
1852 	}
1853 }
1854 
1855 static void mld_dad_timer_expire(unsigned long data)
1856 {
1857 	struct inet6_dev *idev = (struct inet6_dev *)data;
1858 
1859 	mld_resend_report(idev);
1860 	if (idev->mc_dad_count) {
1861 		idev->mc_dad_count--;
1862 		if (idev->mc_dad_count)
1863 			mld_dad_start_timer(idev, idev->mc_maxdelay);
1864 	}
1865 	__in6_dev_put(idev);
1866 }
1867 
1868 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
1869 	const struct in6_addr *psfsrc)
1870 {
1871 	struct ip6_sf_list *psf, *psf_prev;
1872 	int rv = 0;
1873 
1874 	psf_prev = NULL;
1875 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
1876 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
1877 			break;
1878 		psf_prev = psf;
1879 	}
1880 	if (!psf || psf->sf_count[sfmode] == 0) {
1881 		/* source filter not found, or count wrong =>  bug */
1882 		return -ESRCH;
1883 	}
1884 	psf->sf_count[sfmode]--;
1885 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
1886 		struct inet6_dev *idev = pmc->idev;
1887 
1888 		/* no more filters for this source */
1889 		if (psf_prev)
1890 			psf_prev->sf_next = psf->sf_next;
1891 		else
1892 			pmc->mca_sources = psf->sf_next;
1893 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
1894 		    !MLD_V1_SEEN(idev)) {
1895 			psf->sf_crcount = idev->mc_qrv;
1896 			psf->sf_next = pmc->mca_tomb;
1897 			pmc->mca_tomb = psf;
1898 			rv = 1;
1899 		} else
1900 			kfree(psf);
1901 	}
1902 	return rv;
1903 }
1904 
1905 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
1906 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
1907 			  int delta)
1908 {
1909 	struct ifmcaddr6 *pmc;
1910 	int	changerec = 0;
1911 	int	i, err;
1912 
1913 	if (!idev)
1914 		return -ENODEV;
1915 	read_lock_bh(&idev->lock);
1916 	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
1917 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
1918 			break;
1919 	}
1920 	if (!pmc) {
1921 		/* MCA not found?? bug */
1922 		read_unlock_bh(&idev->lock);
1923 		return -ESRCH;
1924 	}
1925 	spin_lock_bh(&pmc->mca_lock);
1926 	sf_markstate(pmc);
1927 	if (!delta) {
1928 		if (!pmc->mca_sfcount[sfmode]) {
1929 			spin_unlock_bh(&pmc->mca_lock);
1930 			read_unlock_bh(&idev->lock);
1931 			return -EINVAL;
1932 		}
1933 		pmc->mca_sfcount[sfmode]--;
1934 	}
1935 	err = 0;
1936 	for (i=0; i<sfcount; i++) {
1937 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
1938 
1939 		changerec |= rv > 0;
1940 		if (!err && rv < 0)
1941 			err = rv;
1942 	}
1943 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
1944 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
1945 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
1946 		struct ip6_sf_list *psf;
1947 
1948 		/* filter mode change */
1949 		pmc->mca_sfmode = MCAST_INCLUDE;
1950 		pmc->mca_crcount = idev->mc_qrv;
1951 		idev->mc_ifc_count = pmc->mca_crcount;
1952 		for (psf=pmc->mca_sources; psf; psf = psf->sf_next)
1953 			psf->sf_crcount = 0;
1954 		mld_ifc_event(pmc->idev);
1955 	} else if (sf_setstate(pmc) || changerec)
1956 		mld_ifc_event(pmc->idev);
1957 	spin_unlock_bh(&pmc->mca_lock);
1958 	read_unlock_bh(&idev->lock);
1959 	return err;
1960 }
1961 
1962 /*
1963  * Add multicast single-source filter to the interface list
1964  */
1965 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
1966 	const struct in6_addr *psfsrc)
1967 {
1968 	struct ip6_sf_list *psf, *psf_prev;
1969 
1970 	psf_prev = NULL;
1971 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
1972 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
1973 			break;
1974 		psf_prev = psf;
1975 	}
1976 	if (!psf) {
1977 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
1978 		if (!psf)
1979 			return -ENOBUFS;
1980 
1981 		psf->sf_addr = *psfsrc;
1982 		if (psf_prev) {
1983 			psf_prev->sf_next = psf;
1984 		} else
1985 			pmc->mca_sources = psf;
1986 	}
1987 	psf->sf_count[sfmode]++;
1988 	return 0;
1989 }
1990 
1991 static void sf_markstate(struct ifmcaddr6 *pmc)
1992 {
1993 	struct ip6_sf_list *psf;
1994 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
1995 
1996 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next)
1997 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1998 			psf->sf_oldin = mca_xcount ==
1999 				psf->sf_count[MCAST_EXCLUDE] &&
2000 				!psf->sf_count[MCAST_INCLUDE];
2001 		} else
2002 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2003 }
2004 
2005 static int sf_setstate(struct ifmcaddr6 *pmc)
2006 {
2007 	struct ip6_sf_list *psf, *dpsf;
2008 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2009 	int qrv = pmc->idev->mc_qrv;
2010 	int new_in, rv;
2011 
2012 	rv = 0;
2013 	for (psf=pmc->mca_sources; psf; psf=psf->sf_next) {
2014 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2015 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2016 				!psf->sf_count[MCAST_INCLUDE];
2017 		} else
2018 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2019 		if (new_in) {
2020 			if (!psf->sf_oldin) {
2021 				struct ip6_sf_list *prev = NULL;
2022 
2023 				for (dpsf=pmc->mca_tomb; dpsf;
2024 				     dpsf=dpsf->sf_next) {
2025 					if (ipv6_addr_equal(&dpsf->sf_addr,
2026 					    &psf->sf_addr))
2027 						break;
2028 					prev = dpsf;
2029 				}
2030 				if (dpsf) {
2031 					if (prev)
2032 						prev->sf_next = dpsf->sf_next;
2033 					else
2034 						pmc->mca_tomb = dpsf->sf_next;
2035 					kfree(dpsf);
2036 				}
2037 				psf->sf_crcount = qrv;
2038 				rv++;
2039 			}
2040 		} else if (psf->sf_oldin) {
2041 			psf->sf_crcount = 0;
2042 			/*
2043 			 * add or update "delete" records if an active filter
2044 			 * is now inactive
2045 			 */
2046 			for (dpsf=pmc->mca_tomb; dpsf; dpsf=dpsf->sf_next)
2047 				if (ipv6_addr_equal(&dpsf->sf_addr,
2048 				    &psf->sf_addr))
2049 					break;
2050 			if (!dpsf) {
2051 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2052 				if (!dpsf)
2053 					continue;
2054 				*dpsf = *psf;
2055 				/* pmc->mca_lock held by callers */
2056 				dpsf->sf_next = pmc->mca_tomb;
2057 				pmc->mca_tomb = dpsf;
2058 			}
2059 			dpsf->sf_crcount = qrv;
2060 			rv++;
2061 		}
2062 	}
2063 	return rv;
2064 }
2065 
2066 /*
2067  * Add multicast source filter list to the interface list
2068  */
2069 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2070 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2071 			  int delta)
2072 {
2073 	struct ifmcaddr6 *pmc;
2074 	int	isexclude;
2075 	int	i, err;
2076 
2077 	if (!idev)
2078 		return -ENODEV;
2079 	read_lock_bh(&idev->lock);
2080 	for (pmc=idev->mc_list; pmc; pmc=pmc->next) {
2081 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2082 			break;
2083 	}
2084 	if (!pmc) {
2085 		/* MCA not found?? bug */
2086 		read_unlock_bh(&idev->lock);
2087 		return -ESRCH;
2088 	}
2089 	spin_lock_bh(&pmc->mca_lock);
2090 
2091 	sf_markstate(pmc);
2092 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2093 	if (!delta)
2094 		pmc->mca_sfcount[sfmode]++;
2095 	err = 0;
2096 	for (i=0; i<sfcount; i++) {
2097 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2098 		if (err)
2099 			break;
2100 	}
2101 	if (err) {
2102 		int j;
2103 
2104 		if (!delta)
2105 			pmc->mca_sfcount[sfmode]--;
2106 		for (j=0; j<i; j++)
2107 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2108 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2109 		struct ip6_sf_list *psf;
2110 
2111 		/* filter mode change */
2112 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2113 			pmc->mca_sfmode = MCAST_EXCLUDE;
2114 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2115 			pmc->mca_sfmode = MCAST_INCLUDE;
2116 		/* else no filters; keep old mode for reports */
2117 
2118 		pmc->mca_crcount = idev->mc_qrv;
2119 		idev->mc_ifc_count = pmc->mca_crcount;
2120 		for (psf=pmc->mca_sources; psf; psf = psf->sf_next)
2121 			psf->sf_crcount = 0;
2122 		mld_ifc_event(idev);
2123 	} else if (sf_setstate(pmc))
2124 		mld_ifc_event(idev);
2125 	spin_unlock_bh(&pmc->mca_lock);
2126 	read_unlock_bh(&idev->lock);
2127 	return err;
2128 }
2129 
2130 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2131 {
2132 	struct ip6_sf_list *psf, *nextpsf;
2133 
2134 	for (psf=pmc->mca_tomb; psf; psf=nextpsf) {
2135 		nextpsf = psf->sf_next;
2136 		kfree(psf);
2137 	}
2138 	pmc->mca_tomb = NULL;
2139 	for (psf=pmc->mca_sources; psf; psf=nextpsf) {
2140 		nextpsf = psf->sf_next;
2141 		kfree(psf);
2142 	}
2143 	pmc->mca_sources = NULL;
2144 	pmc->mca_sfmode = MCAST_EXCLUDE;
2145 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2146 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2147 }
2148 
2149 
2150 static void igmp6_join_group(struct ifmcaddr6 *ma)
2151 {
2152 	unsigned long delay;
2153 
2154 	if (ma->mca_flags & MAF_NOREPORT)
2155 		return;
2156 
2157 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2158 
2159 	delay = net_random() % IGMP6_UNSOLICITED_IVAL;
2160 
2161 	spin_lock_bh(&ma->mca_lock);
2162 	if (del_timer(&ma->mca_timer)) {
2163 		atomic_dec(&ma->mca_refcnt);
2164 		delay = ma->mca_timer.expires - jiffies;
2165 	}
2166 
2167 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2168 		atomic_inc(&ma->mca_refcnt);
2169 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2170 	spin_unlock_bh(&ma->mca_lock);
2171 }
2172 
2173 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2174 			    struct inet6_dev *idev)
2175 {
2176 	int err;
2177 
2178 	/* callers have the socket lock and a write lock on ipv6_sk_mc_lock,
2179 	 * so no other readers or writers of iml or its sflist
2180 	 */
2181 	if (!iml->sflist) {
2182 		/* any-source empty exclude case */
2183 		return ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2184 	}
2185 	err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2186 		iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2187 	sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2188 	iml->sflist = NULL;
2189 	return err;
2190 }
2191 
2192 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2193 {
2194 	if (MLD_V1_SEEN(ma->idev)) {
2195 		if (ma->mca_flags & MAF_LAST_REPORTER)
2196 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2197 				ICMPV6_MGM_REDUCTION);
2198 	} else {
2199 		mld_add_delrec(ma->idev, ma);
2200 		mld_ifc_event(ma->idev);
2201 	}
2202 }
2203 
2204 static void mld_gq_timer_expire(unsigned long data)
2205 {
2206 	struct inet6_dev *idev = (struct inet6_dev *)data;
2207 
2208 	idev->mc_gq_running = 0;
2209 	mld_send_report(idev, NULL);
2210 	__in6_dev_put(idev);
2211 }
2212 
2213 static void mld_ifc_timer_expire(unsigned long data)
2214 {
2215 	struct inet6_dev *idev = (struct inet6_dev *)data;
2216 
2217 	mld_send_cr(idev);
2218 	if (idev->mc_ifc_count) {
2219 		idev->mc_ifc_count--;
2220 		if (idev->mc_ifc_count)
2221 			mld_ifc_start_timer(idev, idev->mc_maxdelay);
2222 	}
2223 	__in6_dev_put(idev);
2224 }
2225 
2226 static void mld_ifc_event(struct inet6_dev *idev)
2227 {
2228 	if (MLD_V1_SEEN(idev))
2229 		return;
2230 	idev->mc_ifc_count = idev->mc_qrv;
2231 	mld_ifc_start_timer(idev, 1);
2232 }
2233 
2234 
2235 static void igmp6_timer_handler(unsigned long data)
2236 {
2237 	struct ifmcaddr6 *ma = (struct ifmcaddr6 *) data;
2238 
2239 	if (MLD_V1_SEEN(ma->idev))
2240 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2241 	else
2242 		mld_send_report(ma->idev, ma);
2243 
2244 	spin_lock(&ma->mca_lock);
2245 	ma->mca_flags |=  MAF_LAST_REPORTER;
2246 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2247 	spin_unlock(&ma->mca_lock);
2248 	ma_put(ma);
2249 }
2250 
2251 /* Device changing type */
2252 
2253 void ipv6_mc_unmap(struct inet6_dev *idev)
2254 {
2255 	struct ifmcaddr6 *i;
2256 
2257 	/* Install multicast list, except for all-nodes (already installed) */
2258 
2259 	read_lock_bh(&idev->lock);
2260 	for (i = idev->mc_list; i; i = i->next)
2261 		igmp6_group_dropped(i);
2262 	read_unlock_bh(&idev->lock);
2263 }
2264 
2265 void ipv6_mc_remap(struct inet6_dev *idev)
2266 {
2267 	ipv6_mc_up(idev);
2268 }
2269 
2270 /* Device going down */
2271 
2272 void ipv6_mc_down(struct inet6_dev *idev)
2273 {
2274 	struct ifmcaddr6 *i;
2275 
2276 	/* Withdraw multicast list */
2277 
2278 	read_lock_bh(&idev->lock);
2279 	idev->mc_ifc_count = 0;
2280 	if (del_timer(&idev->mc_ifc_timer))
2281 		__in6_dev_put(idev);
2282 	idev->mc_gq_running = 0;
2283 	if (del_timer(&idev->mc_gq_timer))
2284 		__in6_dev_put(idev);
2285 	if (del_timer(&idev->mc_dad_timer))
2286 		__in6_dev_put(idev);
2287 
2288 	for (i = idev->mc_list; i; i=i->next)
2289 		igmp6_group_dropped(i);
2290 	read_unlock_bh(&idev->lock);
2291 
2292 	mld_clear_delrec(idev);
2293 }
2294 
2295 
2296 /* Device going up */
2297 
2298 void ipv6_mc_up(struct inet6_dev *idev)
2299 {
2300 	struct ifmcaddr6 *i;
2301 
2302 	/* Install multicast list, except for all-nodes (already installed) */
2303 
2304 	read_lock_bh(&idev->lock);
2305 	for (i = idev->mc_list; i; i=i->next)
2306 		igmp6_group_added(i);
2307 	read_unlock_bh(&idev->lock);
2308 }
2309 
2310 /* IPv6 device initialization. */
2311 
2312 void ipv6_mc_init_dev(struct inet6_dev *idev)
2313 {
2314 	write_lock_bh(&idev->lock);
2315 	spin_lock_init(&idev->mc_lock);
2316 	idev->mc_gq_running = 0;
2317 	setup_timer(&idev->mc_gq_timer, mld_gq_timer_expire,
2318 			(unsigned long)idev);
2319 	idev->mc_tomb = NULL;
2320 	idev->mc_ifc_count = 0;
2321 	setup_timer(&idev->mc_ifc_timer, mld_ifc_timer_expire,
2322 			(unsigned long)idev);
2323 	setup_timer(&idev->mc_dad_timer, mld_dad_timer_expire,
2324 		    (unsigned long)idev);
2325 	idev->mc_qrv = MLD_QRV_DEFAULT;
2326 	idev->mc_maxdelay = IGMP6_UNSOLICITED_IVAL;
2327 	idev->mc_v1_seen = 0;
2328 	write_unlock_bh(&idev->lock);
2329 }
2330 
2331 /*
2332  *	Device is about to be destroyed: clean up.
2333  */
2334 
2335 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2336 {
2337 	struct ifmcaddr6 *i;
2338 
2339 	/* Deactivate timers */
2340 	ipv6_mc_down(idev);
2341 
2342 	/* Delete all-nodes address. */
2343 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2344 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2345 	 * fail.
2346 	 */
2347 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2348 
2349 	if (idev->cnf.forwarding)
2350 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2351 
2352 	write_lock_bh(&idev->lock);
2353 	while ((i = idev->mc_list) != NULL) {
2354 		idev->mc_list = i->next;
2355 		write_unlock_bh(&idev->lock);
2356 
2357 		igmp6_group_dropped(i);
2358 		ma_put(i);
2359 
2360 		write_lock_bh(&idev->lock);
2361 	}
2362 	write_unlock_bh(&idev->lock);
2363 }
2364 
2365 #ifdef CONFIG_PROC_FS
2366 struct igmp6_mc_iter_state {
2367 	struct seq_net_private p;
2368 	struct net_device *dev;
2369 	struct inet6_dev *idev;
2370 };
2371 
2372 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2373 
2374 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2375 {
2376 	struct ifmcaddr6 *im = NULL;
2377 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2378 	struct net *net = seq_file_net(seq);
2379 
2380 	state->idev = NULL;
2381 	for_each_netdev_rcu(net, state->dev) {
2382 		struct inet6_dev *idev;
2383 		idev = __in6_dev_get(state->dev);
2384 		if (!idev)
2385 			continue;
2386 		read_lock_bh(&idev->lock);
2387 		im = idev->mc_list;
2388 		if (im) {
2389 			state->idev = idev;
2390 			break;
2391 		}
2392 		read_unlock_bh(&idev->lock);
2393 	}
2394 	return im;
2395 }
2396 
2397 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2398 {
2399 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2400 
2401 	im = im->next;
2402 	while (!im) {
2403 		if (likely(state->idev != NULL))
2404 			read_unlock_bh(&state->idev->lock);
2405 
2406 		state->dev = next_net_device_rcu(state->dev);
2407 		if (!state->dev) {
2408 			state->idev = NULL;
2409 			break;
2410 		}
2411 		state->idev = __in6_dev_get(state->dev);
2412 		if (!state->idev)
2413 			continue;
2414 		read_lock_bh(&state->idev->lock);
2415 		im = state->idev->mc_list;
2416 	}
2417 	return im;
2418 }
2419 
2420 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2421 {
2422 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2423 	if (im)
2424 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2425 			--pos;
2426 	return pos ? NULL : im;
2427 }
2428 
2429 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2430 	__acquires(RCU)
2431 {
2432 	rcu_read_lock();
2433 	return igmp6_mc_get_idx(seq, *pos);
2434 }
2435 
2436 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2437 {
2438 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2439 
2440 	++*pos;
2441 	return im;
2442 }
2443 
2444 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2445 	__releases(RCU)
2446 {
2447 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2448 
2449 	if (likely(state->idev != NULL)) {
2450 		read_unlock_bh(&state->idev->lock);
2451 		state->idev = NULL;
2452 	}
2453 	state->dev = NULL;
2454 	rcu_read_unlock();
2455 }
2456 
2457 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2458 {
2459 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2460 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2461 
2462 	seq_printf(seq,
2463 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2464 		   state->dev->ifindex, state->dev->name,
2465 		   &im->mca_addr,
2466 		   im->mca_users, im->mca_flags,
2467 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2468 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2469 	return 0;
2470 }
2471 
2472 static const struct seq_operations igmp6_mc_seq_ops = {
2473 	.start	=	igmp6_mc_seq_start,
2474 	.next	=	igmp6_mc_seq_next,
2475 	.stop	=	igmp6_mc_seq_stop,
2476 	.show	=	igmp6_mc_seq_show,
2477 };
2478 
2479 static int igmp6_mc_seq_open(struct inode *inode, struct file *file)
2480 {
2481 	return seq_open_net(inode, file, &igmp6_mc_seq_ops,
2482 			    sizeof(struct igmp6_mc_iter_state));
2483 }
2484 
2485 static const struct file_operations igmp6_mc_seq_fops = {
2486 	.owner		=	THIS_MODULE,
2487 	.open		=	igmp6_mc_seq_open,
2488 	.read		=	seq_read,
2489 	.llseek		=	seq_lseek,
2490 	.release	=	seq_release_net,
2491 };
2492 
2493 struct igmp6_mcf_iter_state {
2494 	struct seq_net_private p;
2495 	struct net_device *dev;
2496 	struct inet6_dev *idev;
2497 	struct ifmcaddr6 *im;
2498 };
2499 
2500 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2501 
2502 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2503 {
2504 	struct ip6_sf_list *psf = NULL;
2505 	struct ifmcaddr6 *im = NULL;
2506 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2507 	struct net *net = seq_file_net(seq);
2508 
2509 	state->idev = NULL;
2510 	state->im = NULL;
2511 	for_each_netdev_rcu(net, state->dev) {
2512 		struct inet6_dev *idev;
2513 		idev = __in6_dev_get(state->dev);
2514 		if (unlikely(idev == NULL))
2515 			continue;
2516 		read_lock_bh(&idev->lock);
2517 		im = idev->mc_list;
2518 		if (likely(im != NULL)) {
2519 			spin_lock_bh(&im->mca_lock);
2520 			psf = im->mca_sources;
2521 			if (likely(psf != NULL)) {
2522 				state->im = im;
2523 				state->idev = idev;
2524 				break;
2525 			}
2526 			spin_unlock_bh(&im->mca_lock);
2527 		}
2528 		read_unlock_bh(&idev->lock);
2529 	}
2530 	return psf;
2531 }
2532 
2533 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2534 {
2535 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2536 
2537 	psf = psf->sf_next;
2538 	while (!psf) {
2539 		spin_unlock_bh(&state->im->mca_lock);
2540 		state->im = state->im->next;
2541 		while (!state->im) {
2542 			if (likely(state->idev != NULL))
2543 				read_unlock_bh(&state->idev->lock);
2544 
2545 			state->dev = next_net_device_rcu(state->dev);
2546 			if (!state->dev) {
2547 				state->idev = NULL;
2548 				goto out;
2549 			}
2550 			state->idev = __in6_dev_get(state->dev);
2551 			if (!state->idev)
2552 				continue;
2553 			read_lock_bh(&state->idev->lock);
2554 			state->im = state->idev->mc_list;
2555 		}
2556 		if (!state->im)
2557 			break;
2558 		spin_lock_bh(&state->im->mca_lock);
2559 		psf = state->im->mca_sources;
2560 	}
2561 out:
2562 	return psf;
2563 }
2564 
2565 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2566 {
2567 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2568 	if (psf)
2569 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2570 			--pos;
2571 	return pos ? NULL : psf;
2572 }
2573 
2574 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2575 	__acquires(RCU)
2576 {
2577 	rcu_read_lock();
2578 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2579 }
2580 
2581 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2582 {
2583 	struct ip6_sf_list *psf;
2584 	if (v == SEQ_START_TOKEN)
2585 		psf = igmp6_mcf_get_first(seq);
2586 	else
2587 		psf = igmp6_mcf_get_next(seq, v);
2588 	++*pos;
2589 	return psf;
2590 }
2591 
2592 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2593 	__releases(RCU)
2594 {
2595 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2596 	if (likely(state->im != NULL)) {
2597 		spin_unlock_bh(&state->im->mca_lock);
2598 		state->im = NULL;
2599 	}
2600 	if (likely(state->idev != NULL)) {
2601 		read_unlock_bh(&state->idev->lock);
2602 		state->idev = NULL;
2603 	}
2604 	state->dev = NULL;
2605 	rcu_read_unlock();
2606 }
2607 
2608 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2609 {
2610 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2611 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2612 
2613 	if (v == SEQ_START_TOKEN) {
2614 		seq_printf(seq,
2615 			   "%3s %6s "
2616 			   "%32s %32s %6s %6s\n", "Idx",
2617 			   "Device", "Multicast Address",
2618 			   "Source Address", "INC", "EXC");
2619 	} else {
2620 		seq_printf(seq,
2621 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2622 			   state->dev->ifindex, state->dev->name,
2623 			   &state->im->mca_addr,
2624 			   &psf->sf_addr,
2625 			   psf->sf_count[MCAST_INCLUDE],
2626 			   psf->sf_count[MCAST_EXCLUDE]);
2627 	}
2628 	return 0;
2629 }
2630 
2631 static const struct seq_operations igmp6_mcf_seq_ops = {
2632 	.start	=	igmp6_mcf_seq_start,
2633 	.next	=	igmp6_mcf_seq_next,
2634 	.stop	=	igmp6_mcf_seq_stop,
2635 	.show	=	igmp6_mcf_seq_show,
2636 };
2637 
2638 static int igmp6_mcf_seq_open(struct inode *inode, struct file *file)
2639 {
2640 	return seq_open_net(inode, file, &igmp6_mcf_seq_ops,
2641 			    sizeof(struct igmp6_mcf_iter_state));
2642 }
2643 
2644 static const struct file_operations igmp6_mcf_seq_fops = {
2645 	.owner		=	THIS_MODULE,
2646 	.open		=	igmp6_mcf_seq_open,
2647 	.read		=	seq_read,
2648 	.llseek		=	seq_lseek,
2649 	.release	=	seq_release_net,
2650 };
2651 
2652 static int __net_init igmp6_proc_init(struct net *net)
2653 {
2654 	int err;
2655 
2656 	err = -ENOMEM;
2657 	if (!proc_create("igmp6", S_IRUGO, net->proc_net, &igmp6_mc_seq_fops))
2658 		goto out;
2659 	if (!proc_create("mcfilter6", S_IRUGO, net->proc_net,
2660 			 &igmp6_mcf_seq_fops))
2661 		goto out_proc_net_igmp6;
2662 
2663 	err = 0;
2664 out:
2665 	return err;
2666 
2667 out_proc_net_igmp6:
2668 	remove_proc_entry("igmp6", net->proc_net);
2669 	goto out;
2670 }
2671 
2672 static void __net_exit igmp6_proc_exit(struct net *net)
2673 {
2674 	remove_proc_entry("mcfilter6", net->proc_net);
2675 	remove_proc_entry("igmp6", net->proc_net);
2676 }
2677 #else
2678 static inline int igmp6_proc_init(struct net *net)
2679 {
2680 	return 0;
2681 }
2682 static inline void igmp6_proc_exit(struct net *net)
2683 {
2684 }
2685 #endif
2686 
2687 static int __net_init igmp6_net_init(struct net *net)
2688 {
2689 	int err;
2690 
2691 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2692 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2693 	if (err < 0) {
2694 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2695 		       err);
2696 		goto out;
2697 	}
2698 
2699 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2700 
2701 	err = igmp6_proc_init(net);
2702 	if (err)
2703 		goto out_sock_create;
2704 out:
2705 	return err;
2706 
2707 out_sock_create:
2708 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2709 	goto out;
2710 }
2711 
2712 static void __net_exit igmp6_net_exit(struct net *net)
2713 {
2714 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2715 	igmp6_proc_exit(net);
2716 }
2717 
2718 static struct pernet_operations igmp6_net_ops = {
2719 	.init = igmp6_net_init,
2720 	.exit = igmp6_net_exit,
2721 };
2722 
2723 int __init igmp6_init(void)
2724 {
2725 	return register_pernet_subsys(&igmp6_net_ops);
2726 }
2727 
2728 void igmp6_cleanup(void)
2729 {
2730 	unregister_pernet_subsys(&igmp6_net_ops);
2731 }
2732