xref: /linux/net/ipv6/addrconf.c (revision 2a2c74b2efcb1a0ca3fdcb5fbb96ad8de6a29177)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/firewire.h>
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/tcp.h>
80 #include <net/ip.h>
81 #include <net/netlink.h>
82 #include <net/pkt_sched.h>
83 #include <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 #include <linux/random.h>
87 #include <linux/uaccess.h>
88 #include <asm/unaligned.h>
89 
90 #include <linux/proc_fs.h>
91 #include <linux/seq_file.h>
92 #include <linux/export.h>
93 
94 /* Set to 3 to get tracing... */
95 #define ACONF_DEBUG 2
96 
97 #if ACONF_DEBUG >= 3
98 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
99 #else
100 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
101 #endif
102 
103 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
104 
105 static inline u32 cstamp_delta(unsigned long cstamp)
106 {
107 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
108 }
109 
110 #ifdef CONFIG_SYSCTL
111 static void addrconf_sysctl_register(struct inet6_dev *idev);
112 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
113 #else
114 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
115 {
116 }
117 
118 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
119 {
120 }
121 #endif
122 
123 static void __ipv6_regen_rndid(struct inet6_dev *idev);
124 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
125 static void ipv6_regen_rndid(unsigned long data);
126 
127 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
128 static int ipv6_count_addresses(struct inet6_dev *idev);
129 
130 /*
131  *	Configured unicast address hash table
132  */
133 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
134 static DEFINE_SPINLOCK(addrconf_hash_lock);
135 
136 static void addrconf_verify(void);
137 static void addrconf_verify_rtnl(void);
138 static void addrconf_verify_work(struct work_struct *);
139 
140 static struct workqueue_struct *addrconf_wq;
141 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
142 
143 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
144 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
145 
146 static void addrconf_type_change(struct net_device *dev,
147 				 unsigned long event);
148 static int addrconf_ifdown(struct net_device *dev, int how);
149 
150 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
151 						  int plen,
152 						  const struct net_device *dev,
153 						  u32 flags, u32 noflags);
154 
155 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
156 static void addrconf_dad_work(struct work_struct *w);
157 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
158 static void addrconf_dad_run(struct inet6_dev *idev);
159 static void addrconf_rs_timer(unsigned long data);
160 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
161 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
162 
163 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
164 				struct prefix_info *pinfo);
165 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
166 			       struct net_device *dev);
167 
168 static struct ipv6_devconf ipv6_devconf __read_mostly = {
169 	.forwarding		= 0,
170 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
171 	.mtu6			= IPV6_MIN_MTU,
172 	.accept_ra		= 1,
173 	.accept_redirects	= 1,
174 	.autoconf		= 1,
175 	.force_mld_version	= 0,
176 	.mldv1_unsolicited_report_interval = 10 * HZ,
177 	.mldv2_unsolicited_report_interval = HZ,
178 	.dad_transmits		= 1,
179 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
180 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
181 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
182 	.use_tempaddr 		= 0,
183 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
184 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
185 	.regen_max_retry	= REGEN_MAX_RETRY,
186 	.max_desync_factor	= MAX_DESYNC_FACTOR,
187 	.max_addresses		= IPV6_MAX_ADDRESSES,
188 	.accept_ra_defrtr	= 1,
189 	.accept_ra_pinfo	= 1,
190 #ifdef CONFIG_IPV6_ROUTER_PREF
191 	.accept_ra_rtr_pref	= 1,
192 	.rtr_probe_interval	= 60 * HZ,
193 #ifdef CONFIG_IPV6_ROUTE_INFO
194 	.accept_ra_rt_info_max_plen = 0,
195 #endif
196 #endif
197 	.proxy_ndp		= 0,
198 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
199 	.disable_ipv6		= 0,
200 	.accept_dad		= 1,
201 	.suppress_frag_ndisc	= 1,
202 };
203 
204 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
205 	.forwarding		= 0,
206 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
207 	.mtu6			= IPV6_MIN_MTU,
208 	.accept_ra		= 1,
209 	.accept_redirects	= 1,
210 	.autoconf		= 1,
211 	.force_mld_version	= 0,
212 	.mldv1_unsolicited_report_interval = 10 * HZ,
213 	.mldv2_unsolicited_report_interval = HZ,
214 	.dad_transmits		= 1,
215 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
216 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
217 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
218 	.use_tempaddr		= 0,
219 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
220 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
221 	.regen_max_retry	= REGEN_MAX_RETRY,
222 	.max_desync_factor	= MAX_DESYNC_FACTOR,
223 	.max_addresses		= IPV6_MAX_ADDRESSES,
224 	.accept_ra_defrtr	= 1,
225 	.accept_ra_pinfo	= 1,
226 #ifdef CONFIG_IPV6_ROUTER_PREF
227 	.accept_ra_rtr_pref	= 1,
228 	.rtr_probe_interval	= 60 * HZ,
229 #ifdef CONFIG_IPV6_ROUTE_INFO
230 	.accept_ra_rt_info_max_plen = 0,
231 #endif
232 #endif
233 	.proxy_ndp		= 0,
234 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
235 	.disable_ipv6		= 0,
236 	.accept_dad		= 1,
237 	.suppress_frag_ndisc	= 1,
238 };
239 
240 /* Check if a valid qdisc is available */
241 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
242 {
243 	return !qdisc_tx_is_noop(dev);
244 }
245 
246 static void addrconf_del_rs_timer(struct inet6_dev *idev)
247 {
248 	if (del_timer(&idev->rs_timer))
249 		__in6_dev_put(idev);
250 }
251 
252 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
253 {
254 	if (cancel_delayed_work(&ifp->dad_work))
255 		__in6_ifa_put(ifp);
256 }
257 
258 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
259 				  unsigned long when)
260 {
261 	if (!timer_pending(&idev->rs_timer))
262 		in6_dev_hold(idev);
263 	mod_timer(&idev->rs_timer, jiffies + when);
264 }
265 
266 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
267 				   unsigned long delay)
268 {
269 	if (!delayed_work_pending(&ifp->dad_work))
270 		in6_ifa_hold(ifp);
271 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
272 }
273 
274 static int snmp6_alloc_dev(struct inet6_dev *idev)
275 {
276 	int i;
277 
278 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
279 			  sizeof(struct ipstats_mib),
280 			  __alignof__(struct ipstats_mib)) < 0)
281 		goto err_ip;
282 
283 	for_each_possible_cpu(i) {
284 		struct ipstats_mib *addrconf_stats;
285 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6[0], i);
286 		u64_stats_init(&addrconf_stats->syncp);
287 #if SNMP_ARRAY_SZ == 2
288 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6[1], i);
289 		u64_stats_init(&addrconf_stats->syncp);
290 #endif
291 	}
292 
293 
294 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
295 					GFP_KERNEL);
296 	if (!idev->stats.icmpv6dev)
297 		goto err_icmp;
298 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
299 					   GFP_KERNEL);
300 	if (!idev->stats.icmpv6msgdev)
301 		goto err_icmpmsg;
302 
303 	return 0;
304 
305 err_icmpmsg:
306 	kfree(idev->stats.icmpv6dev);
307 err_icmp:
308 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
309 err_ip:
310 	return -ENOMEM;
311 }
312 
313 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
314 {
315 	struct inet6_dev *ndev;
316 
317 	ASSERT_RTNL();
318 
319 	if (dev->mtu < IPV6_MIN_MTU)
320 		return NULL;
321 
322 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
323 
324 	if (ndev == NULL)
325 		return NULL;
326 
327 	rwlock_init(&ndev->lock);
328 	ndev->dev = dev;
329 	INIT_LIST_HEAD(&ndev->addr_list);
330 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
331 		    (unsigned long)ndev);
332 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
333 	ndev->cnf.mtu6 = dev->mtu;
334 	ndev->cnf.sysctl = NULL;
335 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
336 	if (ndev->nd_parms == NULL) {
337 		kfree(ndev);
338 		return NULL;
339 	}
340 	if (ndev->cnf.forwarding)
341 		dev_disable_lro(dev);
342 	/* We refer to the device */
343 	dev_hold(dev);
344 
345 	if (snmp6_alloc_dev(ndev) < 0) {
346 		ADBG(KERN_WARNING
347 			"%s: cannot allocate memory for statistics; dev=%s.\n",
348 			__func__, dev->name);
349 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
350 		dev_put(dev);
351 		kfree(ndev);
352 		return NULL;
353 	}
354 
355 	if (snmp6_register_dev(ndev) < 0) {
356 		ADBG(KERN_WARNING
357 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
358 			__func__, dev->name);
359 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
360 		ndev->dead = 1;
361 		in6_dev_finish_destroy(ndev);
362 		return NULL;
363 	}
364 
365 	/* One reference from device.  We must do this before
366 	 * we invoke __ipv6_regen_rndid().
367 	 */
368 	in6_dev_hold(ndev);
369 
370 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
371 		ndev->cnf.accept_dad = -1;
372 
373 #if IS_ENABLED(CONFIG_IPV6_SIT)
374 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
375 		pr_info("%s: Disabled Multicast RS\n", dev->name);
376 		ndev->cnf.rtr_solicits = 0;
377 	}
378 #endif
379 
380 	INIT_LIST_HEAD(&ndev->tempaddr_list);
381 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
382 	if ((dev->flags&IFF_LOOPBACK) ||
383 	    dev->type == ARPHRD_TUNNEL ||
384 	    dev->type == ARPHRD_TUNNEL6 ||
385 	    dev->type == ARPHRD_SIT ||
386 	    dev->type == ARPHRD_NONE) {
387 		ndev->cnf.use_tempaddr = -1;
388 	} else {
389 		in6_dev_hold(ndev);
390 		ipv6_regen_rndid((unsigned long) ndev);
391 	}
392 
393 	ndev->token = in6addr_any;
394 
395 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
396 		ndev->if_flags |= IF_READY;
397 
398 	ipv6_mc_init_dev(ndev);
399 	ndev->tstamp = jiffies;
400 	addrconf_sysctl_register(ndev);
401 	/* protected by rtnl_lock */
402 	rcu_assign_pointer(dev->ip6_ptr, ndev);
403 
404 	/* Join interface-local all-node multicast group */
405 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
406 
407 	/* Join all-node multicast group */
408 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
409 
410 	/* Join all-router multicast group if forwarding is set */
411 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
412 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
413 
414 	return ndev;
415 }
416 
417 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
418 {
419 	struct inet6_dev *idev;
420 
421 	ASSERT_RTNL();
422 
423 	idev = __in6_dev_get(dev);
424 	if (!idev) {
425 		idev = ipv6_add_dev(dev);
426 		if (!idev)
427 			return NULL;
428 	}
429 
430 	if (dev->flags&IFF_UP)
431 		ipv6_mc_up(idev);
432 	return idev;
433 }
434 
435 static int inet6_netconf_msgsize_devconf(int type)
436 {
437 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
438 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
439 
440 	/* type -1 is used for ALL */
441 	if (type == -1 || type == NETCONFA_FORWARDING)
442 		size += nla_total_size(4);
443 #ifdef CONFIG_IPV6_MROUTE
444 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
445 		size += nla_total_size(4);
446 #endif
447 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
448 		size += nla_total_size(4);
449 
450 	return size;
451 }
452 
453 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
454 				      struct ipv6_devconf *devconf, u32 portid,
455 				      u32 seq, int event, unsigned int flags,
456 				      int type)
457 {
458 	struct nlmsghdr  *nlh;
459 	struct netconfmsg *ncm;
460 
461 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
462 			flags);
463 	if (nlh == NULL)
464 		return -EMSGSIZE;
465 
466 	ncm = nlmsg_data(nlh);
467 	ncm->ncm_family = AF_INET6;
468 
469 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
470 		goto nla_put_failure;
471 
472 	/* type -1 is used for ALL */
473 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
474 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
475 		goto nla_put_failure;
476 #ifdef CONFIG_IPV6_MROUTE
477 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
478 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
479 			devconf->mc_forwarding) < 0)
480 		goto nla_put_failure;
481 #endif
482 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
483 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
484 		goto nla_put_failure;
485 
486 	return nlmsg_end(skb, nlh);
487 
488 nla_put_failure:
489 	nlmsg_cancel(skb, nlh);
490 	return -EMSGSIZE;
491 }
492 
493 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
494 				  struct ipv6_devconf *devconf)
495 {
496 	struct sk_buff *skb;
497 	int err = -ENOBUFS;
498 
499 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
500 	if (skb == NULL)
501 		goto errout;
502 
503 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
504 					 RTM_NEWNETCONF, 0, type);
505 	if (err < 0) {
506 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
507 		WARN_ON(err == -EMSGSIZE);
508 		kfree_skb(skb);
509 		goto errout;
510 	}
511 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
512 	return;
513 errout:
514 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
515 }
516 
517 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
518 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
519 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
520 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
521 };
522 
523 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
524 				     struct nlmsghdr *nlh)
525 {
526 	struct net *net = sock_net(in_skb->sk);
527 	struct nlattr *tb[NETCONFA_MAX+1];
528 	struct netconfmsg *ncm;
529 	struct sk_buff *skb;
530 	struct ipv6_devconf *devconf;
531 	struct inet6_dev *in6_dev;
532 	struct net_device *dev;
533 	int ifindex;
534 	int err;
535 
536 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
537 			  devconf_ipv6_policy);
538 	if (err < 0)
539 		goto errout;
540 
541 	err = EINVAL;
542 	if (!tb[NETCONFA_IFINDEX])
543 		goto errout;
544 
545 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
546 	switch (ifindex) {
547 	case NETCONFA_IFINDEX_ALL:
548 		devconf = net->ipv6.devconf_all;
549 		break;
550 	case NETCONFA_IFINDEX_DEFAULT:
551 		devconf = net->ipv6.devconf_dflt;
552 		break;
553 	default:
554 		dev = __dev_get_by_index(net, ifindex);
555 		if (dev == NULL)
556 			goto errout;
557 		in6_dev = __in6_dev_get(dev);
558 		if (in6_dev == NULL)
559 			goto errout;
560 		devconf = &in6_dev->cnf;
561 		break;
562 	}
563 
564 	err = -ENOBUFS;
565 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
566 	if (skb == NULL)
567 		goto errout;
568 
569 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
570 					 NETLINK_CB(in_skb).portid,
571 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
572 					 -1);
573 	if (err < 0) {
574 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
575 		WARN_ON(err == -EMSGSIZE);
576 		kfree_skb(skb);
577 		goto errout;
578 	}
579 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
580 errout:
581 	return err;
582 }
583 
584 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
585 				      struct netlink_callback *cb)
586 {
587 	struct net *net = sock_net(skb->sk);
588 	int h, s_h;
589 	int idx, s_idx;
590 	struct net_device *dev;
591 	struct inet6_dev *idev;
592 	struct hlist_head *head;
593 
594 	s_h = cb->args[0];
595 	s_idx = idx = cb->args[1];
596 
597 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
598 		idx = 0;
599 		head = &net->dev_index_head[h];
600 		rcu_read_lock();
601 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
602 			  net->dev_base_seq;
603 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
604 			if (idx < s_idx)
605 				goto cont;
606 			idev = __in6_dev_get(dev);
607 			if (!idev)
608 				goto cont;
609 
610 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
611 						       &idev->cnf,
612 						       NETLINK_CB(cb->skb).portid,
613 						       cb->nlh->nlmsg_seq,
614 						       RTM_NEWNETCONF,
615 						       NLM_F_MULTI,
616 						       -1) <= 0) {
617 				rcu_read_unlock();
618 				goto done;
619 			}
620 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
621 cont:
622 			idx++;
623 		}
624 		rcu_read_unlock();
625 	}
626 	if (h == NETDEV_HASHENTRIES) {
627 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
628 					       net->ipv6.devconf_all,
629 					       NETLINK_CB(cb->skb).portid,
630 					       cb->nlh->nlmsg_seq,
631 					       RTM_NEWNETCONF, NLM_F_MULTI,
632 					       -1) <= 0)
633 			goto done;
634 		else
635 			h++;
636 	}
637 	if (h == NETDEV_HASHENTRIES + 1) {
638 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
639 					       net->ipv6.devconf_dflt,
640 					       NETLINK_CB(cb->skb).portid,
641 					       cb->nlh->nlmsg_seq,
642 					       RTM_NEWNETCONF, NLM_F_MULTI,
643 					       -1) <= 0)
644 			goto done;
645 		else
646 			h++;
647 	}
648 done:
649 	cb->args[0] = h;
650 	cb->args[1] = idx;
651 
652 	return skb->len;
653 }
654 
655 #ifdef CONFIG_SYSCTL
656 static void dev_forward_change(struct inet6_dev *idev)
657 {
658 	struct net_device *dev;
659 	struct inet6_ifaddr *ifa;
660 
661 	if (!idev)
662 		return;
663 	dev = idev->dev;
664 	if (idev->cnf.forwarding)
665 		dev_disable_lro(dev);
666 	if (dev->flags & IFF_MULTICAST) {
667 		if (idev->cnf.forwarding) {
668 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
669 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
670 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
671 		} else {
672 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
673 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
674 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
675 		}
676 	}
677 
678 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
679 		if (ifa->flags&IFA_F_TENTATIVE)
680 			continue;
681 		if (idev->cnf.forwarding)
682 			addrconf_join_anycast(ifa);
683 		else
684 			addrconf_leave_anycast(ifa);
685 	}
686 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
687 				     dev->ifindex, &idev->cnf);
688 }
689 
690 
691 static void addrconf_forward_change(struct net *net, __s32 newf)
692 {
693 	struct net_device *dev;
694 	struct inet6_dev *idev;
695 
696 	for_each_netdev(net, dev) {
697 		idev = __in6_dev_get(dev);
698 		if (idev) {
699 			int changed = (!idev->cnf.forwarding) ^ (!newf);
700 			idev->cnf.forwarding = newf;
701 			if (changed)
702 				dev_forward_change(idev);
703 		}
704 	}
705 }
706 
707 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
708 {
709 	struct net *net;
710 	int old;
711 
712 	if (!rtnl_trylock())
713 		return restart_syscall();
714 
715 	net = (struct net *)table->extra2;
716 	old = *p;
717 	*p = newf;
718 
719 	if (p == &net->ipv6.devconf_dflt->forwarding) {
720 		if ((!newf) ^ (!old))
721 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
722 						     NETCONFA_IFINDEX_DEFAULT,
723 						     net->ipv6.devconf_dflt);
724 		rtnl_unlock();
725 		return 0;
726 	}
727 
728 	if (p == &net->ipv6.devconf_all->forwarding) {
729 		net->ipv6.devconf_dflt->forwarding = newf;
730 		addrconf_forward_change(net, newf);
731 		if ((!newf) ^ (!old))
732 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
733 						     NETCONFA_IFINDEX_ALL,
734 						     net->ipv6.devconf_all);
735 	} else if ((!newf) ^ (!old))
736 		dev_forward_change((struct inet6_dev *)table->extra1);
737 	rtnl_unlock();
738 
739 	if (newf)
740 		rt6_purge_dflt_routers(net);
741 	return 1;
742 }
743 #endif
744 
745 /* Nobody refers to this ifaddr, destroy it */
746 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
747 {
748 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
749 
750 #ifdef NET_REFCNT_DEBUG
751 	pr_debug("%s\n", __func__);
752 #endif
753 
754 	in6_dev_put(ifp->idev);
755 
756 	if (cancel_delayed_work(&ifp->dad_work))
757 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
758 			  ifp);
759 
760 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
761 		pr_warn("Freeing alive inet6 address %p\n", ifp);
762 		return;
763 	}
764 	ip6_rt_put(ifp->rt);
765 
766 	kfree_rcu(ifp, rcu);
767 }
768 
769 static void
770 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
771 {
772 	struct list_head *p;
773 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
774 
775 	/*
776 	 * Each device address list is sorted in order of scope -
777 	 * global before linklocal.
778 	 */
779 	list_for_each(p, &idev->addr_list) {
780 		struct inet6_ifaddr *ifa
781 			= list_entry(p, struct inet6_ifaddr, if_list);
782 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
783 			break;
784 	}
785 
786 	list_add_tail(&ifp->if_list, p);
787 }
788 
789 static u32 inet6_addr_hash(const struct in6_addr *addr)
790 {
791 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
792 }
793 
794 /* On success it returns ifp with increased reference count */
795 
796 static struct inet6_ifaddr *
797 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
798 	      const struct in6_addr *peer_addr, int pfxlen,
799 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
800 {
801 	struct inet6_ifaddr *ifa = NULL;
802 	struct rt6_info *rt;
803 	unsigned int hash;
804 	int err = 0;
805 	int addr_type = ipv6_addr_type(addr);
806 
807 	if (addr_type == IPV6_ADDR_ANY ||
808 	    addr_type & IPV6_ADDR_MULTICAST ||
809 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
810 	     addr_type & IPV6_ADDR_LOOPBACK))
811 		return ERR_PTR(-EADDRNOTAVAIL);
812 
813 	rcu_read_lock_bh();
814 	if (idev->dead) {
815 		err = -ENODEV;			/*XXX*/
816 		goto out2;
817 	}
818 
819 	if (idev->cnf.disable_ipv6) {
820 		err = -EACCES;
821 		goto out2;
822 	}
823 
824 	spin_lock(&addrconf_hash_lock);
825 
826 	/* Ignore adding duplicate addresses on an interface */
827 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
828 		ADBG("ipv6_add_addr: already assigned\n");
829 		err = -EEXIST;
830 		goto out;
831 	}
832 
833 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
834 
835 	if (ifa == NULL) {
836 		ADBG("ipv6_add_addr: malloc failed\n");
837 		err = -ENOBUFS;
838 		goto out;
839 	}
840 
841 	rt = addrconf_dst_alloc(idev, addr, false);
842 	if (IS_ERR(rt)) {
843 		err = PTR_ERR(rt);
844 		goto out;
845 	}
846 
847 	neigh_parms_data_state_setall(idev->nd_parms);
848 
849 	ifa->addr = *addr;
850 	if (peer_addr)
851 		ifa->peer_addr = *peer_addr;
852 
853 	spin_lock_init(&ifa->lock);
854 	spin_lock_init(&ifa->state_lock);
855 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
856 	INIT_HLIST_NODE(&ifa->addr_lst);
857 	ifa->scope = scope;
858 	ifa->prefix_len = pfxlen;
859 	ifa->flags = flags | IFA_F_TENTATIVE;
860 	ifa->valid_lft = valid_lft;
861 	ifa->prefered_lft = prefered_lft;
862 	ifa->cstamp = ifa->tstamp = jiffies;
863 	ifa->tokenized = false;
864 
865 	ifa->rt = rt;
866 
867 	ifa->idev = idev;
868 	in6_dev_hold(idev);
869 	/* For caller */
870 	in6_ifa_hold(ifa);
871 
872 	/* Add to big hash table */
873 	hash = inet6_addr_hash(addr);
874 
875 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
876 	spin_unlock(&addrconf_hash_lock);
877 
878 	write_lock(&idev->lock);
879 	/* Add to inet6_dev unicast addr list. */
880 	ipv6_link_dev_addr(idev, ifa);
881 
882 	if (ifa->flags&IFA_F_TEMPORARY) {
883 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
884 		in6_ifa_hold(ifa);
885 	}
886 
887 	in6_ifa_hold(ifa);
888 	write_unlock(&idev->lock);
889 out2:
890 	rcu_read_unlock_bh();
891 
892 	if (likely(err == 0))
893 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
894 	else {
895 		kfree(ifa);
896 		ifa = ERR_PTR(err);
897 	}
898 
899 	return ifa;
900 out:
901 	spin_unlock(&addrconf_hash_lock);
902 	goto out2;
903 }
904 
905 enum cleanup_prefix_rt_t {
906 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
907 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
908 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
909 };
910 
911 /*
912  * Check, whether the prefix for ifp would still need a prefix route
913  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
914  * constants.
915  *
916  * 1) we don't purge prefix if address was not permanent.
917  *    prefix is managed by its own lifetime.
918  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
919  * 3) if there are no addresses, delete prefix.
920  * 4) if there are still other permanent address(es),
921  *    corresponding prefix is still permanent.
922  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
923  *    don't purge the prefix, assume user space is managing it.
924  * 6) otherwise, update prefix lifetime to the
925  *    longest valid lifetime among the corresponding
926  *    addresses on the device.
927  *    Note: subsequent RA will update lifetime.
928  **/
929 static enum cleanup_prefix_rt_t
930 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
931 {
932 	struct inet6_ifaddr *ifa;
933 	struct inet6_dev *idev = ifp->idev;
934 	unsigned long lifetime;
935 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
936 
937 	*expires = jiffies;
938 
939 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
940 		if (ifa == ifp)
941 			continue;
942 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
943 				       ifp->prefix_len))
944 			continue;
945 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
946 			return CLEANUP_PREFIX_RT_NOP;
947 
948 		action = CLEANUP_PREFIX_RT_EXPIRE;
949 
950 		spin_lock(&ifa->lock);
951 
952 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
953 		/*
954 		 * Note: Because this address is
955 		 * not permanent, lifetime <
956 		 * LONG_MAX / HZ here.
957 		 */
958 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
959 			*expires = ifa->tstamp + lifetime * HZ;
960 		spin_unlock(&ifa->lock);
961 	}
962 
963 	return action;
964 }
965 
966 static void
967 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
968 {
969 	struct rt6_info *rt;
970 
971 	rt = addrconf_get_prefix_route(&ifp->addr,
972 				       ifp->prefix_len,
973 				       ifp->idev->dev,
974 				       0, RTF_GATEWAY | RTF_DEFAULT);
975 	if (rt) {
976 		if (del_rt)
977 			ip6_del_rt(rt);
978 		else {
979 			if (!(rt->rt6i_flags & RTF_EXPIRES))
980 				rt6_set_expires(rt, expires);
981 			ip6_rt_put(rt);
982 		}
983 	}
984 }
985 
986 
987 /* This function wants to get referenced ifp and releases it before return */
988 
989 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
990 {
991 	int state;
992 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
993 	unsigned long expires;
994 
995 	ASSERT_RTNL();
996 
997 	spin_lock_bh(&ifp->state_lock);
998 	state = ifp->state;
999 	ifp->state = INET6_IFADDR_STATE_DEAD;
1000 	spin_unlock_bh(&ifp->state_lock);
1001 
1002 	if (state == INET6_IFADDR_STATE_DEAD)
1003 		goto out;
1004 
1005 	spin_lock_bh(&addrconf_hash_lock);
1006 	hlist_del_init_rcu(&ifp->addr_lst);
1007 	spin_unlock_bh(&addrconf_hash_lock);
1008 
1009 	write_lock_bh(&ifp->idev->lock);
1010 
1011 	if (ifp->flags&IFA_F_TEMPORARY) {
1012 		list_del(&ifp->tmp_list);
1013 		if (ifp->ifpub) {
1014 			in6_ifa_put(ifp->ifpub);
1015 			ifp->ifpub = NULL;
1016 		}
1017 		__in6_ifa_put(ifp);
1018 	}
1019 
1020 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1021 		action = check_cleanup_prefix_route(ifp, &expires);
1022 
1023 	list_del_init(&ifp->if_list);
1024 	__in6_ifa_put(ifp);
1025 
1026 	write_unlock_bh(&ifp->idev->lock);
1027 
1028 	addrconf_del_dad_work(ifp);
1029 
1030 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1031 
1032 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1033 
1034 	if (action != CLEANUP_PREFIX_RT_NOP) {
1035 		cleanup_prefix_route(ifp, expires,
1036 			action == CLEANUP_PREFIX_RT_DEL);
1037 	}
1038 
1039 	/* clean up prefsrc entries */
1040 	rt6_remove_prefsrc(ifp);
1041 out:
1042 	in6_ifa_put(ifp);
1043 }
1044 
1045 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1046 {
1047 	struct inet6_dev *idev = ifp->idev;
1048 	struct in6_addr addr, *tmpaddr;
1049 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1050 	unsigned long regen_advance;
1051 	int tmp_plen;
1052 	int ret = 0;
1053 	u32 addr_flags;
1054 	unsigned long now = jiffies;
1055 
1056 	write_lock_bh(&idev->lock);
1057 	if (ift) {
1058 		spin_lock_bh(&ift->lock);
1059 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1060 		spin_unlock_bh(&ift->lock);
1061 		tmpaddr = &addr;
1062 	} else {
1063 		tmpaddr = NULL;
1064 	}
1065 retry:
1066 	in6_dev_hold(idev);
1067 	if (idev->cnf.use_tempaddr <= 0) {
1068 		write_unlock_bh(&idev->lock);
1069 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1070 		in6_dev_put(idev);
1071 		ret = -1;
1072 		goto out;
1073 	}
1074 	spin_lock_bh(&ifp->lock);
1075 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1076 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1077 		spin_unlock_bh(&ifp->lock);
1078 		write_unlock_bh(&idev->lock);
1079 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1080 			__func__);
1081 		in6_dev_put(idev);
1082 		ret = -1;
1083 		goto out;
1084 	}
1085 	in6_ifa_hold(ifp);
1086 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1087 	__ipv6_try_regen_rndid(idev, tmpaddr);
1088 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1089 	age = (now - ifp->tstamp) / HZ;
1090 	tmp_valid_lft = min_t(__u32,
1091 			      ifp->valid_lft,
1092 			      idev->cnf.temp_valid_lft + age);
1093 	tmp_prefered_lft = min_t(__u32,
1094 				 ifp->prefered_lft,
1095 				 idev->cnf.temp_prefered_lft + age -
1096 				 idev->cnf.max_desync_factor);
1097 	tmp_plen = ifp->prefix_len;
1098 	tmp_tstamp = ifp->tstamp;
1099 	spin_unlock_bh(&ifp->lock);
1100 
1101 	regen_advance = idev->cnf.regen_max_retry *
1102 	                idev->cnf.dad_transmits *
1103 	                NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1104 	write_unlock_bh(&idev->lock);
1105 
1106 	/* A temporary address is created only if this calculated Preferred
1107 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1108 	 * an implementation must not create a temporary address with a zero
1109 	 * Preferred Lifetime.
1110 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1111 	 * temporary addresses being generated.
1112 	 */
1113 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1114 	if (tmp_prefered_lft <= regen_advance + age) {
1115 		in6_ifa_put(ifp);
1116 		in6_dev_put(idev);
1117 		ret = -1;
1118 		goto out;
1119 	}
1120 
1121 	addr_flags = IFA_F_TEMPORARY;
1122 	/* set in addrconf_prefix_rcv() */
1123 	if (ifp->flags & IFA_F_OPTIMISTIC)
1124 		addr_flags |= IFA_F_OPTIMISTIC;
1125 
1126 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1127 			    ipv6_addr_scope(&addr), addr_flags,
1128 			    tmp_valid_lft, tmp_prefered_lft);
1129 	if (IS_ERR(ift)) {
1130 		in6_ifa_put(ifp);
1131 		in6_dev_put(idev);
1132 		pr_info("%s: retry temporary address regeneration\n", __func__);
1133 		tmpaddr = &addr;
1134 		write_lock_bh(&idev->lock);
1135 		goto retry;
1136 	}
1137 
1138 	spin_lock_bh(&ift->lock);
1139 	ift->ifpub = ifp;
1140 	ift->cstamp = now;
1141 	ift->tstamp = tmp_tstamp;
1142 	spin_unlock_bh(&ift->lock);
1143 
1144 	addrconf_dad_start(ift);
1145 	in6_ifa_put(ift);
1146 	in6_dev_put(idev);
1147 out:
1148 	return ret;
1149 }
1150 
1151 /*
1152  *	Choose an appropriate source address (RFC3484)
1153  */
1154 enum {
1155 	IPV6_SADDR_RULE_INIT = 0,
1156 	IPV6_SADDR_RULE_LOCAL,
1157 	IPV6_SADDR_RULE_SCOPE,
1158 	IPV6_SADDR_RULE_PREFERRED,
1159 #ifdef CONFIG_IPV6_MIP6
1160 	IPV6_SADDR_RULE_HOA,
1161 #endif
1162 	IPV6_SADDR_RULE_OIF,
1163 	IPV6_SADDR_RULE_LABEL,
1164 	IPV6_SADDR_RULE_PRIVACY,
1165 	IPV6_SADDR_RULE_ORCHID,
1166 	IPV6_SADDR_RULE_PREFIX,
1167 	IPV6_SADDR_RULE_MAX
1168 };
1169 
1170 struct ipv6_saddr_score {
1171 	int			rule;
1172 	int			addr_type;
1173 	struct inet6_ifaddr	*ifa;
1174 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1175 	int			scopedist;
1176 	int			matchlen;
1177 };
1178 
1179 struct ipv6_saddr_dst {
1180 	const struct in6_addr *addr;
1181 	int ifindex;
1182 	int scope;
1183 	int label;
1184 	unsigned int prefs;
1185 };
1186 
1187 static inline int ipv6_saddr_preferred(int type)
1188 {
1189 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1190 		return 1;
1191 	return 0;
1192 }
1193 
1194 static int ipv6_get_saddr_eval(struct net *net,
1195 			       struct ipv6_saddr_score *score,
1196 			       struct ipv6_saddr_dst *dst,
1197 			       int i)
1198 {
1199 	int ret;
1200 
1201 	if (i <= score->rule) {
1202 		switch (i) {
1203 		case IPV6_SADDR_RULE_SCOPE:
1204 			ret = score->scopedist;
1205 			break;
1206 		case IPV6_SADDR_RULE_PREFIX:
1207 			ret = score->matchlen;
1208 			break;
1209 		default:
1210 			ret = !!test_bit(i, score->scorebits);
1211 		}
1212 		goto out;
1213 	}
1214 
1215 	switch (i) {
1216 	case IPV6_SADDR_RULE_INIT:
1217 		/* Rule 0: remember if hiscore is not ready yet */
1218 		ret = !!score->ifa;
1219 		break;
1220 	case IPV6_SADDR_RULE_LOCAL:
1221 		/* Rule 1: Prefer same address */
1222 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1223 		break;
1224 	case IPV6_SADDR_RULE_SCOPE:
1225 		/* Rule 2: Prefer appropriate scope
1226 		 *
1227 		 *      ret
1228 		 *       ^
1229 		 *    -1 |  d 15
1230 		 *    ---+--+-+---> scope
1231 		 *       |
1232 		 *       |             d is scope of the destination.
1233 		 *  B-d  |  \
1234 		 *       |   \      <- smaller scope is better if
1235 		 *  B-15 |    \        if scope is enough for destination.
1236 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1237 		 * d-C-1 | /
1238 		 *       |/         <- greater is better
1239 		 *   -C  /             if scope is not enough for destination.
1240 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1241 		 *
1242 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1243 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1244 		 * Assume B = 0 and we get C > 29.
1245 		 */
1246 		ret = __ipv6_addr_src_scope(score->addr_type);
1247 		if (ret >= dst->scope)
1248 			ret = -ret;
1249 		else
1250 			ret -= 128;	/* 30 is enough */
1251 		score->scopedist = ret;
1252 		break;
1253 	case IPV6_SADDR_RULE_PREFERRED:
1254 		/* Rule 3: Avoid deprecated and optimistic addresses */
1255 		ret = ipv6_saddr_preferred(score->addr_type) ||
1256 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1257 		break;
1258 #ifdef CONFIG_IPV6_MIP6
1259 	case IPV6_SADDR_RULE_HOA:
1260 	    {
1261 		/* Rule 4: Prefer home address */
1262 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1263 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1264 		break;
1265 	    }
1266 #endif
1267 	case IPV6_SADDR_RULE_OIF:
1268 		/* Rule 5: Prefer outgoing interface */
1269 		ret = (!dst->ifindex ||
1270 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1271 		break;
1272 	case IPV6_SADDR_RULE_LABEL:
1273 		/* Rule 6: Prefer matching label */
1274 		ret = ipv6_addr_label(net,
1275 				      &score->ifa->addr, score->addr_type,
1276 				      score->ifa->idev->dev->ifindex) == dst->label;
1277 		break;
1278 	case IPV6_SADDR_RULE_PRIVACY:
1279 	    {
1280 		/* Rule 7: Prefer public address
1281 		 * Note: prefer temporary address if use_tempaddr >= 2
1282 		 */
1283 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1284 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1285 				score->ifa->idev->cnf.use_tempaddr >= 2;
1286 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1287 		break;
1288 	    }
1289 	case IPV6_SADDR_RULE_ORCHID:
1290 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1291 		 *	    non-ORCHID vs non-ORCHID
1292 		 */
1293 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1294 			ipv6_addr_orchid(dst->addr));
1295 		break;
1296 	case IPV6_SADDR_RULE_PREFIX:
1297 		/* Rule 8: Use longest matching prefix */
1298 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1299 		if (ret > score->ifa->prefix_len)
1300 			ret = score->ifa->prefix_len;
1301 		score->matchlen = ret;
1302 		break;
1303 	default:
1304 		ret = 0;
1305 	}
1306 
1307 	if (ret)
1308 		__set_bit(i, score->scorebits);
1309 	score->rule = i;
1310 out:
1311 	return ret;
1312 }
1313 
1314 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1315 		       const struct in6_addr *daddr, unsigned int prefs,
1316 		       struct in6_addr *saddr)
1317 {
1318 	struct ipv6_saddr_score scores[2],
1319 				*score = &scores[0], *hiscore = &scores[1];
1320 	struct ipv6_saddr_dst dst;
1321 	struct net_device *dev;
1322 	int dst_type;
1323 
1324 	dst_type = __ipv6_addr_type(daddr);
1325 	dst.addr = daddr;
1326 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1327 	dst.scope = __ipv6_addr_src_scope(dst_type);
1328 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1329 	dst.prefs = prefs;
1330 
1331 	hiscore->rule = -1;
1332 	hiscore->ifa = NULL;
1333 
1334 	rcu_read_lock();
1335 
1336 	for_each_netdev_rcu(net, dev) {
1337 		struct inet6_dev *idev;
1338 
1339 		/* Candidate Source Address (section 4)
1340 		 *  - multicast and link-local destination address,
1341 		 *    the set of candidate source address MUST only
1342 		 *    include addresses assigned to interfaces
1343 		 *    belonging to the same link as the outgoing
1344 		 *    interface.
1345 		 * (- For site-local destination addresses, the
1346 		 *    set of candidate source addresses MUST only
1347 		 *    include addresses assigned to interfaces
1348 		 *    belonging to the same site as the outgoing
1349 		 *    interface.)
1350 		 */
1351 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1352 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1353 		    dst.ifindex && dev->ifindex != dst.ifindex)
1354 			continue;
1355 
1356 		idev = __in6_dev_get(dev);
1357 		if (!idev)
1358 			continue;
1359 
1360 		read_lock_bh(&idev->lock);
1361 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1362 			int i;
1363 
1364 			/*
1365 			 * - Tentative Address (RFC2462 section 5.4)
1366 			 *  - A tentative address is not considered
1367 			 *    "assigned to an interface" in the traditional
1368 			 *    sense, unless it is also flagged as optimistic.
1369 			 * - Candidate Source Address (section 4)
1370 			 *  - In any case, anycast addresses, multicast
1371 			 *    addresses, and the unspecified address MUST
1372 			 *    NOT be included in a candidate set.
1373 			 */
1374 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1375 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1376 				continue;
1377 
1378 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1379 
1380 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1381 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1382 				LIMIT_NETDEBUG(KERN_DEBUG
1383 					       "ADDRCONF: unspecified / multicast address "
1384 					       "assigned as unicast address on %s",
1385 					       dev->name);
1386 				continue;
1387 			}
1388 
1389 			score->rule = -1;
1390 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1391 
1392 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1393 				int minihiscore, miniscore;
1394 
1395 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1396 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1397 
1398 				if (minihiscore > miniscore) {
1399 					if (i == IPV6_SADDR_RULE_SCOPE &&
1400 					    score->scopedist > 0) {
1401 						/*
1402 						 * special case:
1403 						 * each remaining entry
1404 						 * has too small (not enough)
1405 						 * scope, because ifa entries
1406 						 * are sorted by their scope
1407 						 * values.
1408 						 */
1409 						goto try_nextdev;
1410 					}
1411 					break;
1412 				} else if (minihiscore < miniscore) {
1413 					if (hiscore->ifa)
1414 						in6_ifa_put(hiscore->ifa);
1415 
1416 					in6_ifa_hold(score->ifa);
1417 
1418 					swap(hiscore, score);
1419 
1420 					/* restore our iterator */
1421 					score->ifa = hiscore->ifa;
1422 
1423 					break;
1424 				}
1425 			}
1426 		}
1427 try_nextdev:
1428 		read_unlock_bh(&idev->lock);
1429 	}
1430 	rcu_read_unlock();
1431 
1432 	if (!hiscore->ifa)
1433 		return -EADDRNOTAVAIL;
1434 
1435 	*saddr = hiscore->ifa->addr;
1436 	in6_ifa_put(hiscore->ifa);
1437 	return 0;
1438 }
1439 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1440 
1441 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1442 		      u32 banned_flags)
1443 {
1444 	struct inet6_ifaddr *ifp;
1445 	int err = -EADDRNOTAVAIL;
1446 
1447 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1448 		if (ifp->scope > IFA_LINK)
1449 			break;
1450 		if (ifp->scope == IFA_LINK &&
1451 		    !(ifp->flags & banned_flags)) {
1452 			*addr = ifp->addr;
1453 			err = 0;
1454 			break;
1455 		}
1456 	}
1457 	return err;
1458 }
1459 
1460 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1461 		    u32 banned_flags)
1462 {
1463 	struct inet6_dev *idev;
1464 	int err = -EADDRNOTAVAIL;
1465 
1466 	rcu_read_lock();
1467 	idev = __in6_dev_get(dev);
1468 	if (idev) {
1469 		read_lock_bh(&idev->lock);
1470 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1471 		read_unlock_bh(&idev->lock);
1472 	}
1473 	rcu_read_unlock();
1474 	return err;
1475 }
1476 
1477 static int ipv6_count_addresses(struct inet6_dev *idev)
1478 {
1479 	int cnt = 0;
1480 	struct inet6_ifaddr *ifp;
1481 
1482 	read_lock_bh(&idev->lock);
1483 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1484 		cnt++;
1485 	read_unlock_bh(&idev->lock);
1486 	return cnt;
1487 }
1488 
1489 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1490 		  const struct net_device *dev, int strict)
1491 {
1492 	struct inet6_ifaddr *ifp;
1493 	unsigned int hash = inet6_addr_hash(addr);
1494 
1495 	rcu_read_lock_bh();
1496 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1497 		if (!net_eq(dev_net(ifp->idev->dev), net))
1498 			continue;
1499 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1500 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1501 		    (dev == NULL || ifp->idev->dev == dev ||
1502 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1503 			rcu_read_unlock_bh();
1504 			return 1;
1505 		}
1506 	}
1507 
1508 	rcu_read_unlock_bh();
1509 	return 0;
1510 }
1511 EXPORT_SYMBOL(ipv6_chk_addr);
1512 
1513 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1514 			       struct net_device *dev)
1515 {
1516 	unsigned int hash = inet6_addr_hash(addr);
1517 	struct inet6_ifaddr *ifp;
1518 
1519 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1520 		if (!net_eq(dev_net(ifp->idev->dev), net))
1521 			continue;
1522 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1523 			if (dev == NULL || ifp->idev->dev == dev)
1524 				return true;
1525 		}
1526 	}
1527 	return false;
1528 }
1529 
1530 /* Compares an address/prefix_len with addresses on device @dev.
1531  * If one is found it returns true.
1532  */
1533 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1534 	const unsigned int prefix_len, struct net_device *dev)
1535 {
1536 	struct inet6_dev *idev;
1537 	struct inet6_ifaddr *ifa;
1538 	bool ret = false;
1539 
1540 	rcu_read_lock();
1541 	idev = __in6_dev_get(dev);
1542 	if (idev) {
1543 		read_lock_bh(&idev->lock);
1544 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1545 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1546 			if (ret)
1547 				break;
1548 		}
1549 		read_unlock_bh(&idev->lock);
1550 	}
1551 	rcu_read_unlock();
1552 
1553 	return ret;
1554 }
1555 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1556 
1557 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1558 {
1559 	struct inet6_dev *idev;
1560 	struct inet6_ifaddr *ifa;
1561 	int	onlink;
1562 
1563 	onlink = 0;
1564 	rcu_read_lock();
1565 	idev = __in6_dev_get(dev);
1566 	if (idev) {
1567 		read_lock_bh(&idev->lock);
1568 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1569 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1570 						   ifa->prefix_len);
1571 			if (onlink)
1572 				break;
1573 		}
1574 		read_unlock_bh(&idev->lock);
1575 	}
1576 	rcu_read_unlock();
1577 	return onlink;
1578 }
1579 EXPORT_SYMBOL(ipv6_chk_prefix);
1580 
1581 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1582 				     struct net_device *dev, int strict)
1583 {
1584 	struct inet6_ifaddr *ifp, *result = NULL;
1585 	unsigned int hash = inet6_addr_hash(addr);
1586 
1587 	rcu_read_lock_bh();
1588 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1589 		if (!net_eq(dev_net(ifp->idev->dev), net))
1590 			continue;
1591 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1592 			if (dev == NULL || ifp->idev->dev == dev ||
1593 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1594 				result = ifp;
1595 				in6_ifa_hold(ifp);
1596 				break;
1597 			}
1598 		}
1599 	}
1600 	rcu_read_unlock_bh();
1601 
1602 	return result;
1603 }
1604 
1605 /* Gets referenced address, destroys ifaddr */
1606 
1607 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1608 {
1609 	if (ifp->flags&IFA_F_PERMANENT) {
1610 		spin_lock_bh(&ifp->lock);
1611 		addrconf_del_dad_work(ifp);
1612 		ifp->flags |= IFA_F_TENTATIVE;
1613 		if (dad_failed)
1614 			ifp->flags |= IFA_F_DADFAILED;
1615 		spin_unlock_bh(&ifp->lock);
1616 		if (dad_failed)
1617 			ipv6_ifa_notify(0, ifp);
1618 		in6_ifa_put(ifp);
1619 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1620 		struct inet6_ifaddr *ifpub;
1621 		spin_lock_bh(&ifp->lock);
1622 		ifpub = ifp->ifpub;
1623 		if (ifpub) {
1624 			in6_ifa_hold(ifpub);
1625 			spin_unlock_bh(&ifp->lock);
1626 			ipv6_create_tempaddr(ifpub, ifp);
1627 			in6_ifa_put(ifpub);
1628 		} else {
1629 			spin_unlock_bh(&ifp->lock);
1630 		}
1631 		ipv6_del_addr(ifp);
1632 	} else {
1633 		ipv6_del_addr(ifp);
1634 	}
1635 }
1636 
1637 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1638 {
1639 	int err = -ENOENT;
1640 
1641 	spin_lock_bh(&ifp->state_lock);
1642 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1643 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1644 		err = 0;
1645 	}
1646 	spin_unlock_bh(&ifp->state_lock);
1647 
1648 	return err;
1649 }
1650 
1651 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1652 {
1653 	struct inet6_dev *idev = ifp->idev;
1654 
1655 	if (addrconf_dad_end(ifp)) {
1656 		in6_ifa_put(ifp);
1657 		return;
1658 	}
1659 
1660 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1661 			     ifp->idev->dev->name, &ifp->addr);
1662 
1663 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1664 		struct in6_addr addr;
1665 
1666 		addr.s6_addr32[0] = htonl(0xfe800000);
1667 		addr.s6_addr32[1] = 0;
1668 
1669 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1670 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1671 			/* DAD failed for link-local based on MAC address */
1672 			idev->cnf.disable_ipv6 = 1;
1673 
1674 			pr_info("%s: IPv6 being disabled!\n",
1675 				ifp->idev->dev->name);
1676 		}
1677 	}
1678 
1679 	spin_lock_bh(&ifp->state_lock);
1680 	/* transition from _POSTDAD to _ERRDAD */
1681 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1682 	spin_unlock_bh(&ifp->state_lock);
1683 
1684 	addrconf_mod_dad_work(ifp, 0);
1685 }
1686 
1687 /* Join to solicited addr multicast group. */
1688 
1689 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1690 {
1691 	struct in6_addr maddr;
1692 
1693 	ASSERT_RTNL();
1694 
1695 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1696 		return;
1697 
1698 	addrconf_addr_solict_mult(addr, &maddr);
1699 	ipv6_dev_mc_inc(dev, &maddr);
1700 }
1701 
1702 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1703 {
1704 	struct in6_addr maddr;
1705 
1706 	ASSERT_RTNL();
1707 
1708 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1709 		return;
1710 
1711 	addrconf_addr_solict_mult(addr, &maddr);
1712 	__ipv6_dev_mc_dec(idev, &maddr);
1713 }
1714 
1715 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1716 {
1717 	struct in6_addr addr;
1718 
1719 	ASSERT_RTNL();
1720 
1721 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1722 		return;
1723 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1724 	if (ipv6_addr_any(&addr))
1725 		return;
1726 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1727 }
1728 
1729 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1730 {
1731 	struct in6_addr addr;
1732 
1733 	ASSERT_RTNL();
1734 
1735 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1736 		return;
1737 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1738 	if (ipv6_addr_any(&addr))
1739 		return;
1740 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1741 }
1742 
1743 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1744 {
1745 	if (dev->addr_len != ETH_ALEN)
1746 		return -1;
1747 	memcpy(eui, dev->dev_addr, 3);
1748 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1749 
1750 	/*
1751 	 * The zSeries OSA network cards can be shared among various
1752 	 * OS instances, but the OSA cards have only one MAC address.
1753 	 * This leads to duplicate address conflicts in conjunction
1754 	 * with IPv6 if more than one instance uses the same card.
1755 	 *
1756 	 * The driver for these cards can deliver a unique 16-bit
1757 	 * identifier for each instance sharing the same card.  It is
1758 	 * placed instead of 0xFFFE in the interface identifier.  The
1759 	 * "u" bit of the interface identifier is not inverted in this
1760 	 * case.  Hence the resulting interface identifier has local
1761 	 * scope according to RFC2373.
1762 	 */
1763 	if (dev->dev_id) {
1764 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1765 		eui[4] = dev->dev_id & 0xFF;
1766 	} else {
1767 		eui[3] = 0xFF;
1768 		eui[4] = 0xFE;
1769 		eui[0] ^= 2;
1770 	}
1771 	return 0;
1772 }
1773 
1774 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1775 {
1776 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1777 		return -1;
1778 	memcpy(eui, dev->dev_addr, 8);
1779 	eui[0] ^= 2;
1780 	return 0;
1781 }
1782 
1783 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1784 {
1785 	union fwnet_hwaddr *ha;
1786 
1787 	if (dev->addr_len != FWNET_ALEN)
1788 		return -1;
1789 
1790 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1791 
1792 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1793 	eui[0] ^= 2;
1794 	return 0;
1795 }
1796 
1797 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1798 {
1799 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1800 	if (dev->addr_len != ARCNET_ALEN)
1801 		return -1;
1802 	memset(eui, 0, 7);
1803 	eui[7] = *(u8 *)dev->dev_addr;
1804 	return 0;
1805 }
1806 
1807 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1808 {
1809 	if (dev->addr_len != INFINIBAND_ALEN)
1810 		return -1;
1811 	memcpy(eui, dev->dev_addr + 12, 8);
1812 	eui[0] |= 2;
1813 	return 0;
1814 }
1815 
1816 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1817 {
1818 	if (addr == 0)
1819 		return -1;
1820 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1821 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1822 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1823 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1824 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1825 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1826 	eui[1] = 0;
1827 	eui[2] = 0x5E;
1828 	eui[3] = 0xFE;
1829 	memcpy(eui + 4, &addr, 4);
1830 	return 0;
1831 }
1832 
1833 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1834 {
1835 	if (dev->priv_flags & IFF_ISATAP)
1836 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1837 	return -1;
1838 }
1839 
1840 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1841 {
1842 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1843 }
1844 
1845 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1846 {
1847 	memcpy(eui, dev->perm_addr, 3);
1848 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1849 	eui[3] = 0xFF;
1850 	eui[4] = 0xFE;
1851 	eui[0] ^= 2;
1852 	return 0;
1853 }
1854 
1855 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1856 {
1857 	switch (dev->type) {
1858 	case ARPHRD_ETHER:
1859 	case ARPHRD_FDDI:
1860 		return addrconf_ifid_eui48(eui, dev);
1861 	case ARPHRD_ARCNET:
1862 		return addrconf_ifid_arcnet(eui, dev);
1863 	case ARPHRD_INFINIBAND:
1864 		return addrconf_ifid_infiniband(eui, dev);
1865 	case ARPHRD_SIT:
1866 		return addrconf_ifid_sit(eui, dev);
1867 	case ARPHRD_IPGRE:
1868 		return addrconf_ifid_gre(eui, dev);
1869 	case ARPHRD_6LOWPAN:
1870 	case ARPHRD_IEEE802154:
1871 		return addrconf_ifid_eui64(eui, dev);
1872 	case ARPHRD_IEEE1394:
1873 		return addrconf_ifid_ieee1394(eui, dev);
1874 	case ARPHRD_TUNNEL6:
1875 		return addrconf_ifid_ip6tnl(eui, dev);
1876 	}
1877 	return -1;
1878 }
1879 
1880 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1881 {
1882 	int err = -1;
1883 	struct inet6_ifaddr *ifp;
1884 
1885 	read_lock_bh(&idev->lock);
1886 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1887 		if (ifp->scope > IFA_LINK)
1888 			break;
1889 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1890 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1891 			err = 0;
1892 			break;
1893 		}
1894 	}
1895 	read_unlock_bh(&idev->lock);
1896 	return err;
1897 }
1898 
1899 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1900 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1901 {
1902 regen:
1903 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1904 	idev->rndid[0] &= ~0x02;
1905 
1906 	/*
1907 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1908 	 * check if generated address is not inappropriate
1909 	 *
1910 	 *  - Reserved subnet anycast (RFC 2526)
1911 	 *	11111101 11....11 1xxxxxxx
1912 	 *  - ISATAP (RFC4214) 6.1
1913 	 *	00-00-5E-FE-xx-xx-xx-xx
1914 	 *  - value 0
1915 	 *  - XXX: already assigned to an address on the device
1916 	 */
1917 	if (idev->rndid[0] == 0xfd &&
1918 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1919 	    (idev->rndid[7]&0x80))
1920 		goto regen;
1921 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1922 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1923 			goto regen;
1924 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1925 			goto regen;
1926 	}
1927 }
1928 
1929 static void ipv6_regen_rndid(unsigned long data)
1930 {
1931 	struct inet6_dev *idev = (struct inet6_dev *) data;
1932 	unsigned long expires;
1933 
1934 	rcu_read_lock_bh();
1935 	write_lock_bh(&idev->lock);
1936 
1937 	if (idev->dead)
1938 		goto out;
1939 
1940 	__ipv6_regen_rndid(idev);
1941 
1942 	expires = jiffies +
1943 		idev->cnf.temp_prefered_lft * HZ -
1944 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
1945 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
1946 		idev->cnf.max_desync_factor * HZ;
1947 	if (time_before(expires, jiffies)) {
1948 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1949 			__func__, idev->dev->name);
1950 		goto out;
1951 	}
1952 
1953 	if (!mod_timer(&idev->regen_timer, expires))
1954 		in6_dev_hold(idev);
1955 
1956 out:
1957 	write_unlock_bh(&idev->lock);
1958 	rcu_read_unlock_bh();
1959 	in6_dev_put(idev);
1960 }
1961 
1962 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1963 {
1964 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1965 		__ipv6_regen_rndid(idev);
1966 }
1967 
1968 /*
1969  *	Add prefix route.
1970  */
1971 
1972 static void
1973 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1974 		      unsigned long expires, u32 flags)
1975 {
1976 	struct fib6_config cfg = {
1977 		.fc_table = RT6_TABLE_PREFIX,
1978 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1979 		.fc_ifindex = dev->ifindex,
1980 		.fc_expires = expires,
1981 		.fc_dst_len = plen,
1982 		.fc_flags = RTF_UP | flags,
1983 		.fc_nlinfo.nl_net = dev_net(dev),
1984 		.fc_protocol = RTPROT_KERNEL,
1985 	};
1986 
1987 	cfg.fc_dst = *pfx;
1988 
1989 	/* Prevent useless cloning on PtP SIT.
1990 	   This thing is done here expecting that the whole
1991 	   class of non-broadcast devices need not cloning.
1992 	 */
1993 #if IS_ENABLED(CONFIG_IPV6_SIT)
1994 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1995 		cfg.fc_flags |= RTF_NONEXTHOP;
1996 #endif
1997 
1998 	ip6_route_add(&cfg);
1999 }
2000 
2001 
2002 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2003 						  int plen,
2004 						  const struct net_device *dev,
2005 						  u32 flags, u32 noflags)
2006 {
2007 	struct fib6_node *fn;
2008 	struct rt6_info *rt = NULL;
2009 	struct fib6_table *table;
2010 
2011 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
2012 	if (table == NULL)
2013 		return NULL;
2014 
2015 	read_lock_bh(&table->tb6_lock);
2016 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2017 	if (!fn)
2018 		goto out;
2019 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2020 		if (rt->dst.dev->ifindex != dev->ifindex)
2021 			continue;
2022 		if ((rt->rt6i_flags & flags) != flags)
2023 			continue;
2024 		if ((rt->rt6i_flags & noflags) != 0)
2025 			continue;
2026 		dst_hold(&rt->dst);
2027 		break;
2028 	}
2029 out:
2030 	read_unlock_bh(&table->tb6_lock);
2031 	return rt;
2032 }
2033 
2034 
2035 /* Create "default" multicast route to the interface */
2036 
2037 static void addrconf_add_mroute(struct net_device *dev)
2038 {
2039 	struct fib6_config cfg = {
2040 		.fc_table = RT6_TABLE_LOCAL,
2041 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2042 		.fc_ifindex = dev->ifindex,
2043 		.fc_dst_len = 8,
2044 		.fc_flags = RTF_UP,
2045 		.fc_nlinfo.nl_net = dev_net(dev),
2046 	};
2047 
2048 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2049 
2050 	ip6_route_add(&cfg);
2051 }
2052 
2053 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2054 {
2055 	struct inet6_dev *idev;
2056 
2057 	ASSERT_RTNL();
2058 
2059 	idev = ipv6_find_idev(dev);
2060 	if (!idev)
2061 		return ERR_PTR(-ENOBUFS);
2062 
2063 	if (idev->cnf.disable_ipv6)
2064 		return ERR_PTR(-EACCES);
2065 
2066 	/* Add default multicast route */
2067 	if (!(dev->flags & IFF_LOOPBACK))
2068 		addrconf_add_mroute(dev);
2069 
2070 	return idev;
2071 }
2072 
2073 static void manage_tempaddrs(struct inet6_dev *idev,
2074 			     struct inet6_ifaddr *ifp,
2075 			     __u32 valid_lft, __u32 prefered_lft,
2076 			     bool create, unsigned long now)
2077 {
2078 	u32 flags;
2079 	struct inet6_ifaddr *ift;
2080 
2081 	read_lock_bh(&idev->lock);
2082 	/* update all temporary addresses in the list */
2083 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2084 		int age, max_valid, max_prefered;
2085 
2086 		if (ifp != ift->ifpub)
2087 			continue;
2088 
2089 		/* RFC 4941 section 3.3:
2090 		 * If a received option will extend the lifetime of a public
2091 		 * address, the lifetimes of temporary addresses should
2092 		 * be extended, subject to the overall constraint that no
2093 		 * temporary addresses should ever remain "valid" or "preferred"
2094 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2095 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2096 		 */
2097 		age = (now - ift->cstamp) / HZ;
2098 		max_valid = idev->cnf.temp_valid_lft - age;
2099 		if (max_valid < 0)
2100 			max_valid = 0;
2101 
2102 		max_prefered = idev->cnf.temp_prefered_lft -
2103 			       idev->cnf.max_desync_factor - age;
2104 		if (max_prefered < 0)
2105 			max_prefered = 0;
2106 
2107 		if (valid_lft > max_valid)
2108 			valid_lft = max_valid;
2109 
2110 		if (prefered_lft > max_prefered)
2111 			prefered_lft = max_prefered;
2112 
2113 		spin_lock(&ift->lock);
2114 		flags = ift->flags;
2115 		ift->valid_lft = valid_lft;
2116 		ift->prefered_lft = prefered_lft;
2117 		ift->tstamp = now;
2118 		if (prefered_lft > 0)
2119 			ift->flags &= ~IFA_F_DEPRECATED;
2120 
2121 		spin_unlock(&ift->lock);
2122 		if (!(flags&IFA_F_TENTATIVE))
2123 			ipv6_ifa_notify(0, ift);
2124 	}
2125 
2126 	if ((create || list_empty(&idev->tempaddr_list)) &&
2127 	    idev->cnf.use_tempaddr > 0) {
2128 		/* When a new public address is created as described
2129 		 * in [ADDRCONF], also create a new temporary address.
2130 		 * Also create a temporary address if it's enabled but
2131 		 * no temporary address currently exists.
2132 		 */
2133 		read_unlock_bh(&idev->lock);
2134 		ipv6_create_tempaddr(ifp, NULL);
2135 	} else {
2136 		read_unlock_bh(&idev->lock);
2137 	}
2138 }
2139 
2140 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2141 {
2142 	struct prefix_info *pinfo;
2143 	__u32 valid_lft;
2144 	__u32 prefered_lft;
2145 	int addr_type;
2146 	struct inet6_dev *in6_dev;
2147 	struct net *net = dev_net(dev);
2148 
2149 	pinfo = (struct prefix_info *) opt;
2150 
2151 	if (len < sizeof(struct prefix_info)) {
2152 		ADBG("addrconf: prefix option too short\n");
2153 		return;
2154 	}
2155 
2156 	/*
2157 	 *	Validation checks ([ADDRCONF], page 19)
2158 	 */
2159 
2160 	addr_type = ipv6_addr_type(&pinfo->prefix);
2161 
2162 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2163 		return;
2164 
2165 	valid_lft = ntohl(pinfo->valid);
2166 	prefered_lft = ntohl(pinfo->prefered);
2167 
2168 	if (prefered_lft > valid_lft) {
2169 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2170 		return;
2171 	}
2172 
2173 	in6_dev = in6_dev_get(dev);
2174 
2175 	if (in6_dev == NULL) {
2176 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2177 				    dev->name);
2178 		return;
2179 	}
2180 
2181 	/*
2182 	 *	Two things going on here:
2183 	 *	1) Add routes for on-link prefixes
2184 	 *	2) Configure prefixes with the auto flag set
2185 	 */
2186 
2187 	if (pinfo->onlink) {
2188 		struct rt6_info *rt;
2189 		unsigned long rt_expires;
2190 
2191 		/* Avoid arithmetic overflow. Really, we could
2192 		 * save rt_expires in seconds, likely valid_lft,
2193 		 * but it would require division in fib gc, that it
2194 		 * not good.
2195 		 */
2196 		if (HZ > USER_HZ)
2197 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2198 		else
2199 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2200 
2201 		if (addrconf_finite_timeout(rt_expires))
2202 			rt_expires *= HZ;
2203 
2204 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2205 					       pinfo->prefix_len,
2206 					       dev,
2207 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2208 					       RTF_GATEWAY | RTF_DEFAULT);
2209 
2210 		if (rt) {
2211 			/* Autoconf prefix route */
2212 			if (valid_lft == 0) {
2213 				ip6_del_rt(rt);
2214 				rt = NULL;
2215 			} else if (addrconf_finite_timeout(rt_expires)) {
2216 				/* not infinity */
2217 				rt6_set_expires(rt, jiffies + rt_expires);
2218 			} else {
2219 				rt6_clean_expires(rt);
2220 			}
2221 		} else if (valid_lft) {
2222 			clock_t expires = 0;
2223 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2224 			if (addrconf_finite_timeout(rt_expires)) {
2225 				/* not infinity */
2226 				flags |= RTF_EXPIRES;
2227 				expires = jiffies_to_clock_t(rt_expires);
2228 			}
2229 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2230 					      dev, expires, flags);
2231 		}
2232 		ip6_rt_put(rt);
2233 	}
2234 
2235 	/* Try to figure out our local address for this prefix */
2236 
2237 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2238 		struct inet6_ifaddr *ifp;
2239 		struct in6_addr addr;
2240 		int create = 0, update_lft = 0;
2241 		bool tokenized = false;
2242 
2243 		if (pinfo->prefix_len == 64) {
2244 			memcpy(&addr, &pinfo->prefix, 8);
2245 
2246 			if (!ipv6_addr_any(&in6_dev->token)) {
2247 				read_lock_bh(&in6_dev->lock);
2248 				memcpy(addr.s6_addr + 8,
2249 				       in6_dev->token.s6_addr + 8, 8);
2250 				read_unlock_bh(&in6_dev->lock);
2251 				tokenized = true;
2252 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2253 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2254 				in6_dev_put(in6_dev);
2255 				return;
2256 			}
2257 			goto ok;
2258 		}
2259 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2260 				    pinfo->prefix_len);
2261 		in6_dev_put(in6_dev);
2262 		return;
2263 
2264 ok:
2265 
2266 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2267 
2268 		if (ifp == NULL && valid_lft) {
2269 			int max_addresses = in6_dev->cnf.max_addresses;
2270 			u32 addr_flags = 0;
2271 
2272 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2273 			if (in6_dev->cnf.optimistic_dad &&
2274 			    !net->ipv6.devconf_all->forwarding && sllao)
2275 				addr_flags = IFA_F_OPTIMISTIC;
2276 #endif
2277 
2278 			/* Do not allow to create too much of autoconfigured
2279 			 * addresses; this would be too easy way to crash kernel.
2280 			 */
2281 			if (!max_addresses ||
2282 			    ipv6_count_addresses(in6_dev) < max_addresses)
2283 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2284 						    pinfo->prefix_len,
2285 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2286 						    addr_flags, valid_lft,
2287 						    prefered_lft);
2288 
2289 			if (IS_ERR_OR_NULL(ifp)) {
2290 				in6_dev_put(in6_dev);
2291 				return;
2292 			}
2293 
2294 			update_lft = 0;
2295 			create = 1;
2296 			spin_lock_bh(&ifp->lock);
2297 			ifp->flags |= IFA_F_MANAGETEMPADDR;
2298 			ifp->cstamp = jiffies;
2299 			ifp->tokenized = tokenized;
2300 			spin_unlock_bh(&ifp->lock);
2301 			addrconf_dad_start(ifp);
2302 		}
2303 
2304 		if (ifp) {
2305 			u32 flags;
2306 			unsigned long now;
2307 			u32 stored_lft;
2308 
2309 			/* update lifetime (RFC2462 5.5.3 e) */
2310 			spin_lock(&ifp->lock);
2311 			now = jiffies;
2312 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2313 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2314 			else
2315 				stored_lft = 0;
2316 			if (!update_lft && !create && stored_lft) {
2317 				const u32 minimum_lft = min(
2318 					stored_lft, (u32)MIN_VALID_LIFETIME);
2319 				valid_lft = max(valid_lft, minimum_lft);
2320 
2321 				/* RFC4862 Section 5.5.3e:
2322 				 * "Note that the preferred lifetime of the
2323 				 *  corresponding address is always reset to
2324 				 *  the Preferred Lifetime in the received
2325 				 *  Prefix Information option, regardless of
2326 				 *  whether the valid lifetime is also reset or
2327 				 *  ignored."
2328 				 *
2329 				 * So we should always update prefered_lft here.
2330 				 */
2331 				update_lft = 1;
2332 			}
2333 
2334 			if (update_lft) {
2335 				ifp->valid_lft = valid_lft;
2336 				ifp->prefered_lft = prefered_lft;
2337 				ifp->tstamp = now;
2338 				flags = ifp->flags;
2339 				ifp->flags &= ~IFA_F_DEPRECATED;
2340 				spin_unlock(&ifp->lock);
2341 
2342 				if (!(flags&IFA_F_TENTATIVE))
2343 					ipv6_ifa_notify(0, ifp);
2344 			} else
2345 				spin_unlock(&ifp->lock);
2346 
2347 			manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2348 					 create, now);
2349 
2350 			in6_ifa_put(ifp);
2351 			addrconf_verify();
2352 		}
2353 	}
2354 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2355 	in6_dev_put(in6_dev);
2356 }
2357 
2358 /*
2359  *	Set destination address.
2360  *	Special case for SIT interfaces where we create a new "virtual"
2361  *	device.
2362  */
2363 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2364 {
2365 	struct in6_ifreq ireq;
2366 	struct net_device *dev;
2367 	int err = -EINVAL;
2368 
2369 	rtnl_lock();
2370 
2371 	err = -EFAULT;
2372 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2373 		goto err_exit;
2374 
2375 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2376 
2377 	err = -ENODEV;
2378 	if (dev == NULL)
2379 		goto err_exit;
2380 
2381 #if IS_ENABLED(CONFIG_IPV6_SIT)
2382 	if (dev->type == ARPHRD_SIT) {
2383 		const struct net_device_ops *ops = dev->netdev_ops;
2384 		struct ifreq ifr;
2385 		struct ip_tunnel_parm p;
2386 
2387 		err = -EADDRNOTAVAIL;
2388 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2389 			goto err_exit;
2390 
2391 		memset(&p, 0, sizeof(p));
2392 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2393 		p.iph.saddr = 0;
2394 		p.iph.version = 4;
2395 		p.iph.ihl = 5;
2396 		p.iph.protocol = IPPROTO_IPV6;
2397 		p.iph.ttl = 64;
2398 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2399 
2400 		if (ops->ndo_do_ioctl) {
2401 			mm_segment_t oldfs = get_fs();
2402 
2403 			set_fs(KERNEL_DS);
2404 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2405 			set_fs(oldfs);
2406 		} else
2407 			err = -EOPNOTSUPP;
2408 
2409 		if (err == 0) {
2410 			err = -ENOBUFS;
2411 			dev = __dev_get_by_name(net, p.name);
2412 			if (!dev)
2413 				goto err_exit;
2414 			err = dev_open(dev);
2415 		}
2416 	}
2417 #endif
2418 
2419 err_exit:
2420 	rtnl_unlock();
2421 	return err;
2422 }
2423 
2424 /*
2425  *	Manual configuration of address on an interface
2426  */
2427 static int inet6_addr_add(struct net *net, int ifindex,
2428 			  const struct in6_addr *pfx,
2429 			  const struct in6_addr *peer_pfx,
2430 			  unsigned int plen, __u32 ifa_flags,
2431 			  __u32 prefered_lft, __u32 valid_lft)
2432 {
2433 	struct inet6_ifaddr *ifp;
2434 	struct inet6_dev *idev;
2435 	struct net_device *dev;
2436 	int scope;
2437 	u32 flags;
2438 	clock_t expires;
2439 	unsigned long timeout;
2440 
2441 	ASSERT_RTNL();
2442 
2443 	if (plen > 128)
2444 		return -EINVAL;
2445 
2446 	/* check the lifetime */
2447 	if (!valid_lft || prefered_lft > valid_lft)
2448 		return -EINVAL;
2449 
2450 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2451 		return -EINVAL;
2452 
2453 	dev = __dev_get_by_index(net, ifindex);
2454 	if (!dev)
2455 		return -ENODEV;
2456 
2457 	idev = addrconf_add_dev(dev);
2458 	if (IS_ERR(idev))
2459 		return PTR_ERR(idev);
2460 
2461 	scope = ipv6_addr_scope(pfx);
2462 
2463 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2464 	if (addrconf_finite_timeout(timeout)) {
2465 		expires = jiffies_to_clock_t(timeout * HZ);
2466 		valid_lft = timeout;
2467 		flags = RTF_EXPIRES;
2468 	} else {
2469 		expires = 0;
2470 		flags = 0;
2471 		ifa_flags |= IFA_F_PERMANENT;
2472 	}
2473 
2474 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2475 	if (addrconf_finite_timeout(timeout)) {
2476 		if (timeout == 0)
2477 			ifa_flags |= IFA_F_DEPRECATED;
2478 		prefered_lft = timeout;
2479 	}
2480 
2481 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2482 			    valid_lft, prefered_lft);
2483 
2484 	if (!IS_ERR(ifp)) {
2485 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2486 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2487 					      expires, flags);
2488 		}
2489 
2490 		/*
2491 		 * Note that section 3.1 of RFC 4429 indicates
2492 		 * that the Optimistic flag should not be set for
2493 		 * manually configured addresses
2494 		 */
2495 		addrconf_dad_start(ifp);
2496 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2497 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2498 					 true, jiffies);
2499 		in6_ifa_put(ifp);
2500 		addrconf_verify_rtnl();
2501 		return 0;
2502 	}
2503 
2504 	return PTR_ERR(ifp);
2505 }
2506 
2507 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2508 			  unsigned int plen)
2509 {
2510 	struct inet6_ifaddr *ifp;
2511 	struct inet6_dev *idev;
2512 	struct net_device *dev;
2513 
2514 	if (plen > 128)
2515 		return -EINVAL;
2516 
2517 	dev = __dev_get_by_index(net, ifindex);
2518 	if (!dev)
2519 		return -ENODEV;
2520 
2521 	if ((idev = __in6_dev_get(dev)) == NULL)
2522 		return -ENXIO;
2523 
2524 	read_lock_bh(&idev->lock);
2525 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2526 		if (ifp->prefix_len == plen &&
2527 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2528 			in6_ifa_hold(ifp);
2529 			read_unlock_bh(&idev->lock);
2530 
2531 			ipv6_del_addr(ifp);
2532 			return 0;
2533 		}
2534 	}
2535 	read_unlock_bh(&idev->lock);
2536 	return -EADDRNOTAVAIL;
2537 }
2538 
2539 
2540 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2541 {
2542 	struct in6_ifreq ireq;
2543 	int err;
2544 
2545 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2546 		return -EPERM;
2547 
2548 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2549 		return -EFAULT;
2550 
2551 	rtnl_lock();
2552 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2553 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2554 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2555 	rtnl_unlock();
2556 	return err;
2557 }
2558 
2559 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2560 {
2561 	struct in6_ifreq ireq;
2562 	int err;
2563 
2564 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2565 		return -EPERM;
2566 
2567 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2568 		return -EFAULT;
2569 
2570 	rtnl_lock();
2571 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2572 			     ireq.ifr6_prefixlen);
2573 	rtnl_unlock();
2574 	return err;
2575 }
2576 
2577 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2578 		     int plen, int scope)
2579 {
2580 	struct inet6_ifaddr *ifp;
2581 
2582 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2583 			    scope, IFA_F_PERMANENT,
2584 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2585 	if (!IS_ERR(ifp)) {
2586 		spin_lock_bh(&ifp->lock);
2587 		ifp->flags &= ~IFA_F_TENTATIVE;
2588 		spin_unlock_bh(&ifp->lock);
2589 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2590 		in6_ifa_put(ifp);
2591 	}
2592 }
2593 
2594 #if IS_ENABLED(CONFIG_IPV6_SIT)
2595 static void sit_add_v4_addrs(struct inet6_dev *idev)
2596 {
2597 	struct in6_addr addr;
2598 	struct net_device *dev;
2599 	struct net *net = dev_net(idev->dev);
2600 	int scope, plen;
2601 	u32 pflags = 0;
2602 
2603 	ASSERT_RTNL();
2604 
2605 	memset(&addr, 0, sizeof(struct in6_addr));
2606 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2607 
2608 	if (idev->dev->flags&IFF_POINTOPOINT) {
2609 		addr.s6_addr32[0] = htonl(0xfe800000);
2610 		scope = IFA_LINK;
2611 		plen = 64;
2612 	} else {
2613 		scope = IPV6_ADDR_COMPATv4;
2614 		plen = 96;
2615 		pflags |= RTF_NONEXTHOP;
2616 	}
2617 
2618 	if (addr.s6_addr32[3]) {
2619 		add_addr(idev, &addr, plen, scope);
2620 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2621 		return;
2622 	}
2623 
2624 	for_each_netdev(net, dev) {
2625 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2626 		if (in_dev && (dev->flags & IFF_UP)) {
2627 			struct in_ifaddr *ifa;
2628 
2629 			int flag = scope;
2630 
2631 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2632 
2633 				addr.s6_addr32[3] = ifa->ifa_local;
2634 
2635 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2636 					continue;
2637 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2638 					if (idev->dev->flags&IFF_POINTOPOINT)
2639 						continue;
2640 					flag |= IFA_HOST;
2641 				}
2642 
2643 				add_addr(idev, &addr, plen, flag);
2644 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
2645 						      pflags);
2646 			}
2647 		}
2648 	}
2649 }
2650 #endif
2651 
2652 static void init_loopback(struct net_device *dev)
2653 {
2654 	struct inet6_dev  *idev;
2655 	struct net_device *sp_dev;
2656 	struct inet6_ifaddr *sp_ifa;
2657 	struct rt6_info *sp_rt;
2658 
2659 	/* ::1 */
2660 
2661 	ASSERT_RTNL();
2662 
2663 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2664 		pr_debug("%s: add_dev failed\n", __func__);
2665 		return;
2666 	}
2667 
2668 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2669 
2670 	/* Add routes to other interface's IPv6 addresses */
2671 	for_each_netdev(dev_net(dev), sp_dev) {
2672 		if (!strcmp(sp_dev->name, dev->name))
2673 			continue;
2674 
2675 		idev = __in6_dev_get(sp_dev);
2676 		if (!idev)
2677 			continue;
2678 
2679 		read_lock_bh(&idev->lock);
2680 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
2681 
2682 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
2683 				continue;
2684 
2685 			if (sp_ifa->rt) {
2686 				/* This dst has been added to garbage list when
2687 				 * lo device down, release this obsolete dst and
2688 				 * reallocate a new router for ifa.
2689 				 */
2690 				if (sp_ifa->rt->dst.obsolete > 0) {
2691 					ip6_rt_put(sp_ifa->rt);
2692 					sp_ifa->rt = NULL;
2693 				} else {
2694 					continue;
2695 				}
2696 			}
2697 
2698 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
2699 
2700 			/* Failure cases are ignored */
2701 			if (!IS_ERR(sp_rt)) {
2702 				sp_ifa->rt = sp_rt;
2703 				ip6_ins_rt(sp_rt);
2704 			}
2705 		}
2706 		read_unlock_bh(&idev->lock);
2707 	}
2708 }
2709 
2710 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2711 {
2712 	struct inet6_ifaddr *ifp;
2713 	u32 addr_flags = IFA_F_PERMANENT;
2714 
2715 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2716 	if (idev->cnf.optimistic_dad &&
2717 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2718 		addr_flags |= IFA_F_OPTIMISTIC;
2719 #endif
2720 
2721 
2722 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
2723 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2724 	if (!IS_ERR(ifp)) {
2725 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2726 		addrconf_dad_start(ifp);
2727 		in6_ifa_put(ifp);
2728 	}
2729 }
2730 
2731 static void addrconf_dev_config(struct net_device *dev)
2732 {
2733 	struct in6_addr addr;
2734 	struct inet6_dev *idev;
2735 
2736 	ASSERT_RTNL();
2737 
2738 	if ((dev->type != ARPHRD_ETHER) &&
2739 	    (dev->type != ARPHRD_FDDI) &&
2740 	    (dev->type != ARPHRD_ARCNET) &&
2741 	    (dev->type != ARPHRD_INFINIBAND) &&
2742 	    (dev->type != ARPHRD_IEEE802154) &&
2743 	    (dev->type != ARPHRD_IEEE1394) &&
2744 	    (dev->type != ARPHRD_TUNNEL6) &&
2745 	    (dev->type != ARPHRD_6LOWPAN)) {
2746 		/* Alas, we support only Ethernet autoconfiguration. */
2747 		return;
2748 	}
2749 
2750 	idev = addrconf_add_dev(dev);
2751 	if (IS_ERR(idev))
2752 		return;
2753 
2754 	memset(&addr, 0, sizeof(struct in6_addr));
2755 	addr.s6_addr32[0] = htonl(0xFE800000);
2756 
2757 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2758 		addrconf_add_linklocal(idev, &addr);
2759 }
2760 
2761 #if IS_ENABLED(CONFIG_IPV6_SIT)
2762 static void addrconf_sit_config(struct net_device *dev)
2763 {
2764 	struct inet6_dev *idev;
2765 
2766 	ASSERT_RTNL();
2767 
2768 	/*
2769 	 * Configure the tunnel with one of our IPv4
2770 	 * addresses... we should configure all of
2771 	 * our v4 addrs in the tunnel
2772 	 */
2773 
2774 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2775 		pr_debug("%s: add_dev failed\n", __func__);
2776 		return;
2777 	}
2778 
2779 	if (dev->priv_flags & IFF_ISATAP) {
2780 		struct in6_addr addr;
2781 
2782 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2783 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2784 			addrconf_add_linklocal(idev, &addr);
2785 		return;
2786 	}
2787 
2788 	sit_add_v4_addrs(idev);
2789 
2790 	if (dev->flags&IFF_POINTOPOINT)
2791 		addrconf_add_mroute(dev);
2792 }
2793 #endif
2794 
2795 #if IS_ENABLED(CONFIG_NET_IPGRE)
2796 static void addrconf_gre_config(struct net_device *dev)
2797 {
2798 	struct inet6_dev *idev;
2799 	struct in6_addr addr;
2800 
2801 	ASSERT_RTNL();
2802 
2803 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2804 		pr_debug("%s: add_dev failed\n", __func__);
2805 		return;
2806 	}
2807 
2808 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2809 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2810 		addrconf_add_linklocal(idev, &addr);
2811 	else
2812 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2813 }
2814 #endif
2815 
2816 static inline int
2817 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2818 {
2819 	struct in6_addr lladdr;
2820 
2821 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2822 		addrconf_add_linklocal(idev, &lladdr);
2823 		return 0;
2824 	}
2825 	return -1;
2826 }
2827 
2828 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2829 			   void *ptr)
2830 {
2831 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2832 	struct inet6_dev *idev = __in6_dev_get(dev);
2833 	int run_pending = 0;
2834 	int err;
2835 
2836 	switch (event) {
2837 	case NETDEV_REGISTER:
2838 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2839 			idev = ipv6_add_dev(dev);
2840 			if (!idev)
2841 				return notifier_from_errno(-ENOMEM);
2842 		}
2843 		break;
2844 
2845 	case NETDEV_UP:
2846 	case NETDEV_CHANGE:
2847 		if (dev->flags & IFF_SLAVE)
2848 			break;
2849 
2850 		if (event == NETDEV_UP) {
2851 			if (!addrconf_qdisc_ok(dev)) {
2852 				/* device is not ready yet. */
2853 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2854 					dev->name);
2855 				break;
2856 			}
2857 
2858 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2859 				idev = ipv6_add_dev(dev);
2860 
2861 			if (idev) {
2862 				idev->if_flags |= IF_READY;
2863 				run_pending = 1;
2864 			}
2865 		} else {
2866 			if (!addrconf_qdisc_ok(dev)) {
2867 				/* device is still not ready. */
2868 				break;
2869 			}
2870 
2871 			if (idev) {
2872 				if (idev->if_flags & IF_READY)
2873 					/* device is already configured. */
2874 					break;
2875 				idev->if_flags |= IF_READY;
2876 			}
2877 
2878 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2879 				dev->name);
2880 
2881 			run_pending = 1;
2882 		}
2883 
2884 		switch (dev->type) {
2885 #if IS_ENABLED(CONFIG_IPV6_SIT)
2886 		case ARPHRD_SIT:
2887 			addrconf_sit_config(dev);
2888 			break;
2889 #endif
2890 #if IS_ENABLED(CONFIG_NET_IPGRE)
2891 		case ARPHRD_IPGRE:
2892 			addrconf_gre_config(dev);
2893 			break;
2894 #endif
2895 		case ARPHRD_LOOPBACK:
2896 			init_loopback(dev);
2897 			break;
2898 
2899 		default:
2900 			addrconf_dev_config(dev);
2901 			break;
2902 		}
2903 
2904 		if (idev) {
2905 			if (run_pending)
2906 				addrconf_dad_run(idev);
2907 
2908 			/*
2909 			 * If the MTU changed during the interface down,
2910 			 * when the interface up, the changed MTU must be
2911 			 * reflected in the idev as well as routers.
2912 			 */
2913 			if (idev->cnf.mtu6 != dev->mtu &&
2914 			    dev->mtu >= IPV6_MIN_MTU) {
2915 				rt6_mtu_change(dev, dev->mtu);
2916 				idev->cnf.mtu6 = dev->mtu;
2917 			}
2918 			idev->tstamp = jiffies;
2919 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2920 
2921 			/*
2922 			 * If the changed mtu during down is lower than
2923 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2924 			 */
2925 			if (dev->mtu < IPV6_MIN_MTU)
2926 				addrconf_ifdown(dev, 1);
2927 		}
2928 		break;
2929 
2930 	case NETDEV_CHANGEMTU:
2931 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2932 			rt6_mtu_change(dev, dev->mtu);
2933 			idev->cnf.mtu6 = dev->mtu;
2934 			break;
2935 		}
2936 
2937 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2938 			idev = ipv6_add_dev(dev);
2939 			if (idev)
2940 				break;
2941 		}
2942 
2943 		/*
2944 		 * if MTU under IPV6_MIN_MTU.
2945 		 * Stop IPv6 on this interface.
2946 		 */
2947 
2948 	case NETDEV_DOWN:
2949 	case NETDEV_UNREGISTER:
2950 		/*
2951 		 *	Remove all addresses from this interface.
2952 		 */
2953 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2954 		break;
2955 
2956 	case NETDEV_CHANGENAME:
2957 		if (idev) {
2958 			snmp6_unregister_dev(idev);
2959 			addrconf_sysctl_unregister(idev);
2960 			addrconf_sysctl_register(idev);
2961 			err = snmp6_register_dev(idev);
2962 			if (err)
2963 				return notifier_from_errno(err);
2964 		}
2965 		break;
2966 
2967 	case NETDEV_PRE_TYPE_CHANGE:
2968 	case NETDEV_POST_TYPE_CHANGE:
2969 		addrconf_type_change(dev, event);
2970 		break;
2971 	}
2972 
2973 	return NOTIFY_OK;
2974 }
2975 
2976 /*
2977  *	addrconf module should be notified of a device going up
2978  */
2979 static struct notifier_block ipv6_dev_notf = {
2980 	.notifier_call = addrconf_notify,
2981 };
2982 
2983 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2984 {
2985 	struct inet6_dev *idev;
2986 	ASSERT_RTNL();
2987 
2988 	idev = __in6_dev_get(dev);
2989 
2990 	if (event == NETDEV_POST_TYPE_CHANGE)
2991 		ipv6_mc_remap(idev);
2992 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2993 		ipv6_mc_unmap(idev);
2994 }
2995 
2996 static int addrconf_ifdown(struct net_device *dev, int how)
2997 {
2998 	struct net *net = dev_net(dev);
2999 	struct inet6_dev *idev;
3000 	struct inet6_ifaddr *ifa;
3001 	int state, i;
3002 
3003 	ASSERT_RTNL();
3004 
3005 	rt6_ifdown(net, dev);
3006 	neigh_ifdown(&nd_tbl, dev);
3007 
3008 	idev = __in6_dev_get(dev);
3009 	if (idev == NULL)
3010 		return -ENODEV;
3011 
3012 	/*
3013 	 * Step 1: remove reference to ipv6 device from parent device.
3014 	 *	   Do not dev_put!
3015 	 */
3016 	if (how) {
3017 		idev->dead = 1;
3018 
3019 		/* protected by rtnl_lock */
3020 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3021 
3022 		/* Step 1.5: remove snmp6 entry */
3023 		snmp6_unregister_dev(idev);
3024 
3025 	}
3026 
3027 	/* Step 2: clear hash table */
3028 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3029 		struct hlist_head *h = &inet6_addr_lst[i];
3030 
3031 		spin_lock_bh(&addrconf_hash_lock);
3032 	restart:
3033 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3034 			if (ifa->idev == idev) {
3035 				hlist_del_init_rcu(&ifa->addr_lst);
3036 				addrconf_del_dad_work(ifa);
3037 				goto restart;
3038 			}
3039 		}
3040 		spin_unlock_bh(&addrconf_hash_lock);
3041 	}
3042 
3043 	write_lock_bh(&idev->lock);
3044 
3045 	addrconf_del_rs_timer(idev);
3046 
3047 	/* Step 2: clear flags for stateless addrconf */
3048 	if (!how)
3049 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3050 
3051 	if (how && del_timer(&idev->regen_timer))
3052 		in6_dev_put(idev);
3053 
3054 	/* Step 3: clear tempaddr list */
3055 	while (!list_empty(&idev->tempaddr_list)) {
3056 		ifa = list_first_entry(&idev->tempaddr_list,
3057 				       struct inet6_ifaddr, tmp_list);
3058 		list_del(&ifa->tmp_list);
3059 		write_unlock_bh(&idev->lock);
3060 		spin_lock_bh(&ifa->lock);
3061 
3062 		if (ifa->ifpub) {
3063 			in6_ifa_put(ifa->ifpub);
3064 			ifa->ifpub = NULL;
3065 		}
3066 		spin_unlock_bh(&ifa->lock);
3067 		in6_ifa_put(ifa);
3068 		write_lock_bh(&idev->lock);
3069 	}
3070 
3071 	while (!list_empty(&idev->addr_list)) {
3072 		ifa = list_first_entry(&idev->addr_list,
3073 				       struct inet6_ifaddr, if_list);
3074 		addrconf_del_dad_work(ifa);
3075 
3076 		list_del(&ifa->if_list);
3077 
3078 		write_unlock_bh(&idev->lock);
3079 
3080 		spin_lock_bh(&ifa->state_lock);
3081 		state = ifa->state;
3082 		ifa->state = INET6_IFADDR_STATE_DEAD;
3083 		spin_unlock_bh(&ifa->state_lock);
3084 
3085 		if (state != INET6_IFADDR_STATE_DEAD) {
3086 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3087 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3088 		}
3089 		in6_ifa_put(ifa);
3090 
3091 		write_lock_bh(&idev->lock);
3092 	}
3093 
3094 	write_unlock_bh(&idev->lock);
3095 
3096 	/* Step 5: Discard multicast list */
3097 	if (how)
3098 		ipv6_mc_destroy_dev(idev);
3099 	else
3100 		ipv6_mc_down(idev);
3101 
3102 	idev->tstamp = jiffies;
3103 
3104 	/* Last: Shot the device (if unregistered) */
3105 	if (how) {
3106 		addrconf_sysctl_unregister(idev);
3107 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3108 		neigh_ifdown(&nd_tbl, dev);
3109 		in6_dev_put(idev);
3110 	}
3111 	return 0;
3112 }
3113 
3114 static void addrconf_rs_timer(unsigned long data)
3115 {
3116 	struct inet6_dev *idev = (struct inet6_dev *)data;
3117 	struct net_device *dev = idev->dev;
3118 	struct in6_addr lladdr;
3119 
3120 	write_lock(&idev->lock);
3121 	if (idev->dead || !(idev->if_flags & IF_READY))
3122 		goto out;
3123 
3124 	if (!ipv6_accept_ra(idev))
3125 		goto out;
3126 
3127 	/* Announcement received after solicitation was sent */
3128 	if (idev->if_flags & IF_RA_RCVD)
3129 		goto out;
3130 
3131 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3132 		write_unlock(&idev->lock);
3133 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3134 			ndisc_send_rs(dev, &lladdr,
3135 				      &in6addr_linklocal_allrouters);
3136 		else
3137 			goto put;
3138 
3139 		write_lock(&idev->lock);
3140 		/* The wait after the last probe can be shorter */
3141 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3142 					     idev->cnf.rtr_solicits) ?
3143 				      idev->cnf.rtr_solicit_delay :
3144 				      idev->cnf.rtr_solicit_interval);
3145 	} else {
3146 		/*
3147 		 * Note: we do not support deprecated "all on-link"
3148 		 * assumption any longer.
3149 		 */
3150 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3151 	}
3152 
3153 out:
3154 	write_unlock(&idev->lock);
3155 put:
3156 	in6_dev_put(idev);
3157 }
3158 
3159 /*
3160  *	Duplicate Address Detection
3161  */
3162 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3163 {
3164 	unsigned long rand_num;
3165 	struct inet6_dev *idev = ifp->idev;
3166 
3167 	if (ifp->flags & IFA_F_OPTIMISTIC)
3168 		rand_num = 0;
3169 	else
3170 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3171 
3172 	ifp->dad_probes = idev->cnf.dad_transmits;
3173 	addrconf_mod_dad_work(ifp, rand_num);
3174 }
3175 
3176 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3177 {
3178 	struct inet6_dev *idev = ifp->idev;
3179 	struct net_device *dev = idev->dev;
3180 
3181 	addrconf_join_solict(dev, &ifp->addr);
3182 
3183 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3184 
3185 	read_lock_bh(&idev->lock);
3186 	spin_lock(&ifp->lock);
3187 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3188 		goto out;
3189 
3190 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3191 	    idev->cnf.accept_dad < 1 ||
3192 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3193 	    ifp->flags & IFA_F_NODAD) {
3194 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3195 		spin_unlock(&ifp->lock);
3196 		read_unlock_bh(&idev->lock);
3197 
3198 		addrconf_dad_completed(ifp);
3199 		return;
3200 	}
3201 
3202 	if (!(idev->if_flags & IF_READY)) {
3203 		spin_unlock(&ifp->lock);
3204 		read_unlock_bh(&idev->lock);
3205 		/*
3206 		 * If the device is not ready:
3207 		 * - keep it tentative if it is a permanent address.
3208 		 * - otherwise, kill it.
3209 		 */
3210 		in6_ifa_hold(ifp);
3211 		addrconf_dad_stop(ifp, 0);
3212 		return;
3213 	}
3214 
3215 	/*
3216 	 * Optimistic nodes can start receiving
3217 	 * Frames right away
3218 	 */
3219 	if (ifp->flags & IFA_F_OPTIMISTIC)
3220 		ip6_ins_rt(ifp->rt);
3221 
3222 	addrconf_dad_kick(ifp);
3223 out:
3224 	spin_unlock(&ifp->lock);
3225 	read_unlock_bh(&idev->lock);
3226 }
3227 
3228 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3229 {
3230 	bool begin_dad = false;
3231 
3232 	spin_lock_bh(&ifp->state_lock);
3233 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3234 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3235 		begin_dad = true;
3236 	}
3237 	spin_unlock_bh(&ifp->state_lock);
3238 
3239 	if (begin_dad)
3240 		addrconf_mod_dad_work(ifp, 0);
3241 }
3242 
3243 static void addrconf_dad_work(struct work_struct *w)
3244 {
3245 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3246 						struct inet6_ifaddr,
3247 						dad_work);
3248 	struct inet6_dev *idev = ifp->idev;
3249 	struct in6_addr mcaddr;
3250 
3251 	enum {
3252 		DAD_PROCESS,
3253 		DAD_BEGIN,
3254 		DAD_ABORT,
3255 	} action = DAD_PROCESS;
3256 
3257 	rtnl_lock();
3258 
3259 	spin_lock_bh(&ifp->state_lock);
3260 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3261 		action = DAD_BEGIN;
3262 		ifp->state = INET6_IFADDR_STATE_DAD;
3263 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3264 		action = DAD_ABORT;
3265 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3266 	}
3267 	spin_unlock_bh(&ifp->state_lock);
3268 
3269 	if (action == DAD_BEGIN) {
3270 		addrconf_dad_begin(ifp);
3271 		goto out;
3272 	} else if (action == DAD_ABORT) {
3273 		addrconf_dad_stop(ifp, 1);
3274 		goto out;
3275 	}
3276 
3277 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3278 		goto out;
3279 
3280 	write_lock_bh(&idev->lock);
3281 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3282 		write_unlock_bh(&idev->lock);
3283 		goto out;
3284 	}
3285 
3286 	spin_lock(&ifp->lock);
3287 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3288 		spin_unlock(&ifp->lock);
3289 		write_unlock_bh(&idev->lock);
3290 		goto out;
3291 	}
3292 
3293 	if (ifp->dad_probes == 0) {
3294 		/*
3295 		 * DAD was successful
3296 		 */
3297 
3298 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3299 		spin_unlock(&ifp->lock);
3300 		write_unlock_bh(&idev->lock);
3301 
3302 		addrconf_dad_completed(ifp);
3303 
3304 		goto out;
3305 	}
3306 
3307 	ifp->dad_probes--;
3308 	addrconf_mod_dad_work(ifp,
3309 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3310 	spin_unlock(&ifp->lock);
3311 	write_unlock_bh(&idev->lock);
3312 
3313 	/* send a neighbour solicitation for our addr */
3314 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3315 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3316 out:
3317 	in6_ifa_put(ifp);
3318 	rtnl_unlock();
3319 }
3320 
3321 /* ifp->idev must be at least read locked */
3322 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3323 {
3324 	struct inet6_ifaddr *ifpiter;
3325 	struct inet6_dev *idev = ifp->idev;
3326 
3327 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3328 		if (ifpiter->scope > IFA_LINK)
3329 			break;
3330 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3331 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3332 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3333 		    IFA_F_PERMANENT)
3334 			return false;
3335 	}
3336 	return true;
3337 }
3338 
3339 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3340 {
3341 	struct net_device *dev = ifp->idev->dev;
3342 	struct in6_addr lladdr;
3343 	bool send_rs, send_mld;
3344 
3345 	addrconf_del_dad_work(ifp);
3346 
3347 	/*
3348 	 *	Configure the address for reception. Now it is valid.
3349 	 */
3350 
3351 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3352 
3353 	/* If added prefix is link local and we are prepared to process
3354 	   router advertisements, start sending router solicitations.
3355 	 */
3356 
3357 	read_lock_bh(&ifp->idev->lock);
3358 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3359 	send_rs = send_mld &&
3360 		  ipv6_accept_ra(ifp->idev) &&
3361 		  ifp->idev->cnf.rtr_solicits > 0 &&
3362 		  (dev->flags&IFF_LOOPBACK) == 0;
3363 	read_unlock_bh(&ifp->idev->lock);
3364 
3365 	/* While dad is in progress mld report's source address is in6_addrany.
3366 	 * Resend with proper ll now.
3367 	 */
3368 	if (send_mld)
3369 		ipv6_mc_dad_complete(ifp->idev);
3370 
3371 	if (send_rs) {
3372 		/*
3373 		 *	If a host as already performed a random delay
3374 		 *	[...] as part of DAD [...] there is no need
3375 		 *	to delay again before sending the first RS
3376 		 */
3377 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3378 			return;
3379 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3380 
3381 		write_lock_bh(&ifp->idev->lock);
3382 		spin_lock(&ifp->lock);
3383 		ifp->idev->rs_probes = 1;
3384 		ifp->idev->if_flags |= IF_RS_SENT;
3385 		addrconf_mod_rs_timer(ifp->idev,
3386 				      ifp->idev->cnf.rtr_solicit_interval);
3387 		spin_unlock(&ifp->lock);
3388 		write_unlock_bh(&ifp->idev->lock);
3389 	}
3390 }
3391 
3392 static void addrconf_dad_run(struct inet6_dev *idev)
3393 {
3394 	struct inet6_ifaddr *ifp;
3395 
3396 	read_lock_bh(&idev->lock);
3397 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3398 		spin_lock(&ifp->lock);
3399 		if (ifp->flags & IFA_F_TENTATIVE &&
3400 		    ifp->state == INET6_IFADDR_STATE_DAD)
3401 			addrconf_dad_kick(ifp);
3402 		spin_unlock(&ifp->lock);
3403 	}
3404 	read_unlock_bh(&idev->lock);
3405 }
3406 
3407 #ifdef CONFIG_PROC_FS
3408 struct if6_iter_state {
3409 	struct seq_net_private p;
3410 	int bucket;
3411 	int offset;
3412 };
3413 
3414 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3415 {
3416 	struct inet6_ifaddr *ifa = NULL;
3417 	struct if6_iter_state *state = seq->private;
3418 	struct net *net = seq_file_net(seq);
3419 	int p = 0;
3420 
3421 	/* initial bucket if pos is 0 */
3422 	if (pos == 0) {
3423 		state->bucket = 0;
3424 		state->offset = 0;
3425 	}
3426 
3427 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3428 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3429 					 addr_lst) {
3430 			if (!net_eq(dev_net(ifa->idev->dev), net))
3431 				continue;
3432 			/* sync with offset */
3433 			if (p < state->offset) {
3434 				p++;
3435 				continue;
3436 			}
3437 			state->offset++;
3438 			return ifa;
3439 		}
3440 
3441 		/* prepare for next bucket */
3442 		state->offset = 0;
3443 		p = 0;
3444 	}
3445 	return NULL;
3446 }
3447 
3448 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3449 					 struct inet6_ifaddr *ifa)
3450 {
3451 	struct if6_iter_state *state = seq->private;
3452 	struct net *net = seq_file_net(seq);
3453 
3454 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3455 		if (!net_eq(dev_net(ifa->idev->dev), net))
3456 			continue;
3457 		state->offset++;
3458 		return ifa;
3459 	}
3460 
3461 	while (++state->bucket < IN6_ADDR_HSIZE) {
3462 		state->offset = 0;
3463 		hlist_for_each_entry_rcu_bh(ifa,
3464 				     &inet6_addr_lst[state->bucket], addr_lst) {
3465 			if (!net_eq(dev_net(ifa->idev->dev), net))
3466 				continue;
3467 			state->offset++;
3468 			return ifa;
3469 		}
3470 	}
3471 
3472 	return NULL;
3473 }
3474 
3475 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3476 	__acquires(rcu_bh)
3477 {
3478 	rcu_read_lock_bh();
3479 	return if6_get_first(seq, *pos);
3480 }
3481 
3482 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3483 {
3484 	struct inet6_ifaddr *ifa;
3485 
3486 	ifa = if6_get_next(seq, v);
3487 	++*pos;
3488 	return ifa;
3489 }
3490 
3491 static void if6_seq_stop(struct seq_file *seq, void *v)
3492 	__releases(rcu_bh)
3493 {
3494 	rcu_read_unlock_bh();
3495 }
3496 
3497 static int if6_seq_show(struct seq_file *seq, void *v)
3498 {
3499 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3500 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3501 		   &ifp->addr,
3502 		   ifp->idev->dev->ifindex,
3503 		   ifp->prefix_len,
3504 		   ifp->scope,
3505 		   (u8) ifp->flags,
3506 		   ifp->idev->dev->name);
3507 	return 0;
3508 }
3509 
3510 static const struct seq_operations if6_seq_ops = {
3511 	.start	= if6_seq_start,
3512 	.next	= if6_seq_next,
3513 	.show	= if6_seq_show,
3514 	.stop	= if6_seq_stop,
3515 };
3516 
3517 static int if6_seq_open(struct inode *inode, struct file *file)
3518 {
3519 	return seq_open_net(inode, file, &if6_seq_ops,
3520 			    sizeof(struct if6_iter_state));
3521 }
3522 
3523 static const struct file_operations if6_fops = {
3524 	.owner		= THIS_MODULE,
3525 	.open		= if6_seq_open,
3526 	.read		= seq_read,
3527 	.llseek		= seq_lseek,
3528 	.release	= seq_release_net,
3529 };
3530 
3531 static int __net_init if6_proc_net_init(struct net *net)
3532 {
3533 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3534 		return -ENOMEM;
3535 	return 0;
3536 }
3537 
3538 static void __net_exit if6_proc_net_exit(struct net *net)
3539 {
3540 	remove_proc_entry("if_inet6", net->proc_net);
3541 }
3542 
3543 static struct pernet_operations if6_proc_net_ops = {
3544        .init = if6_proc_net_init,
3545        .exit = if6_proc_net_exit,
3546 };
3547 
3548 int __init if6_proc_init(void)
3549 {
3550 	return register_pernet_subsys(&if6_proc_net_ops);
3551 }
3552 
3553 void if6_proc_exit(void)
3554 {
3555 	unregister_pernet_subsys(&if6_proc_net_ops);
3556 }
3557 #endif	/* CONFIG_PROC_FS */
3558 
3559 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3560 /* Check if address is a home address configured on any interface. */
3561 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3562 {
3563 	int ret = 0;
3564 	struct inet6_ifaddr *ifp = NULL;
3565 	unsigned int hash = inet6_addr_hash(addr);
3566 
3567 	rcu_read_lock_bh();
3568 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3569 		if (!net_eq(dev_net(ifp->idev->dev), net))
3570 			continue;
3571 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3572 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3573 			ret = 1;
3574 			break;
3575 		}
3576 	}
3577 	rcu_read_unlock_bh();
3578 	return ret;
3579 }
3580 #endif
3581 
3582 /*
3583  *	Periodic address status verification
3584  */
3585 
3586 static void addrconf_verify_rtnl(void)
3587 {
3588 	unsigned long now, next, next_sec, next_sched;
3589 	struct inet6_ifaddr *ifp;
3590 	int i;
3591 
3592 	ASSERT_RTNL();
3593 
3594 	rcu_read_lock_bh();
3595 	now = jiffies;
3596 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3597 
3598 	cancel_delayed_work(&addr_chk_work);
3599 
3600 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3601 restart:
3602 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
3603 			unsigned long age;
3604 
3605 			/* When setting preferred_lft to a value not zero or
3606 			 * infinity, while valid_lft is infinity
3607 			 * IFA_F_PERMANENT has a non-infinity life time.
3608 			 */
3609 			if ((ifp->flags & IFA_F_PERMANENT) &&
3610 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3611 				continue;
3612 
3613 			spin_lock(&ifp->lock);
3614 			/* We try to batch several events at once. */
3615 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3616 
3617 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3618 			    age >= ifp->valid_lft) {
3619 				spin_unlock(&ifp->lock);
3620 				in6_ifa_hold(ifp);
3621 				ipv6_del_addr(ifp);
3622 				goto restart;
3623 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3624 				spin_unlock(&ifp->lock);
3625 				continue;
3626 			} else if (age >= ifp->prefered_lft) {
3627 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3628 				int deprecate = 0;
3629 
3630 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3631 					deprecate = 1;
3632 					ifp->flags |= IFA_F_DEPRECATED;
3633 				}
3634 
3635 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3636 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3637 					next = ifp->tstamp + ifp->valid_lft * HZ;
3638 
3639 				spin_unlock(&ifp->lock);
3640 
3641 				if (deprecate) {
3642 					in6_ifa_hold(ifp);
3643 
3644 					ipv6_ifa_notify(0, ifp);
3645 					in6_ifa_put(ifp);
3646 					goto restart;
3647 				}
3648 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3649 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3650 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3651 					ifp->idev->cnf.dad_transmits *
3652 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
3653 
3654 				if (age >= ifp->prefered_lft - regen_advance) {
3655 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3656 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3657 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3658 					if (!ifp->regen_count && ifpub) {
3659 						ifp->regen_count++;
3660 						in6_ifa_hold(ifp);
3661 						in6_ifa_hold(ifpub);
3662 						spin_unlock(&ifp->lock);
3663 
3664 						spin_lock(&ifpub->lock);
3665 						ifpub->regen_count = 0;
3666 						spin_unlock(&ifpub->lock);
3667 						ipv6_create_tempaddr(ifpub, ifp);
3668 						in6_ifa_put(ifpub);
3669 						in6_ifa_put(ifp);
3670 						goto restart;
3671 					}
3672 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3673 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3674 				spin_unlock(&ifp->lock);
3675 			} else {
3676 				/* ifp->prefered_lft <= ifp->valid_lft */
3677 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3678 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3679 				spin_unlock(&ifp->lock);
3680 			}
3681 		}
3682 	}
3683 
3684 	next_sec = round_jiffies_up(next);
3685 	next_sched = next;
3686 
3687 	/* If rounded timeout is accurate enough, accept it. */
3688 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3689 		next_sched = next_sec;
3690 
3691 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3692 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3693 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3694 
3695 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3696 	      now, next, next_sec, next_sched);
3697 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
3698 	rcu_read_unlock_bh();
3699 }
3700 
3701 static void addrconf_verify_work(struct work_struct *w)
3702 {
3703 	rtnl_lock();
3704 	addrconf_verify_rtnl();
3705 	rtnl_unlock();
3706 }
3707 
3708 static void addrconf_verify(void)
3709 {
3710 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
3711 }
3712 
3713 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3714 				     struct in6_addr **peer_pfx)
3715 {
3716 	struct in6_addr *pfx = NULL;
3717 
3718 	*peer_pfx = NULL;
3719 
3720 	if (addr)
3721 		pfx = nla_data(addr);
3722 
3723 	if (local) {
3724 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3725 			*peer_pfx = pfx;
3726 		pfx = nla_data(local);
3727 	}
3728 
3729 	return pfx;
3730 }
3731 
3732 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3733 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3734 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3735 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3736 	[IFA_FLAGS]		= { .len = sizeof(u32) },
3737 };
3738 
3739 static int
3740 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3741 {
3742 	struct net *net = sock_net(skb->sk);
3743 	struct ifaddrmsg *ifm;
3744 	struct nlattr *tb[IFA_MAX+1];
3745 	struct in6_addr *pfx, *peer_pfx;
3746 	int err;
3747 
3748 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3749 	if (err < 0)
3750 		return err;
3751 
3752 	ifm = nlmsg_data(nlh);
3753 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3754 	if (pfx == NULL)
3755 		return -EINVAL;
3756 
3757 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3758 }
3759 
3760 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
3761 			     u32 prefered_lft, u32 valid_lft)
3762 {
3763 	u32 flags;
3764 	clock_t expires;
3765 	unsigned long timeout;
3766 	bool was_managetempaddr;
3767 	bool had_prefixroute;
3768 
3769 	ASSERT_RTNL();
3770 
3771 	if (!valid_lft || (prefered_lft > valid_lft))
3772 		return -EINVAL;
3773 
3774 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
3775 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
3776 		return -EINVAL;
3777 
3778 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3779 	if (addrconf_finite_timeout(timeout)) {
3780 		expires = jiffies_to_clock_t(timeout * HZ);
3781 		valid_lft = timeout;
3782 		flags = RTF_EXPIRES;
3783 	} else {
3784 		expires = 0;
3785 		flags = 0;
3786 		ifa_flags |= IFA_F_PERMANENT;
3787 	}
3788 
3789 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3790 	if (addrconf_finite_timeout(timeout)) {
3791 		if (timeout == 0)
3792 			ifa_flags |= IFA_F_DEPRECATED;
3793 		prefered_lft = timeout;
3794 	}
3795 
3796 	spin_lock_bh(&ifp->lock);
3797 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
3798 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
3799 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
3800 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
3801 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3802 			IFA_F_NOPREFIXROUTE);
3803 	ifp->flags |= ifa_flags;
3804 	ifp->tstamp = jiffies;
3805 	ifp->valid_lft = valid_lft;
3806 	ifp->prefered_lft = prefered_lft;
3807 
3808 	spin_unlock_bh(&ifp->lock);
3809 	if (!(ifp->flags&IFA_F_TENTATIVE))
3810 		ipv6_ifa_notify(0, ifp);
3811 
3812 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
3813 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3814 				      expires, flags);
3815 	} else if (had_prefixroute) {
3816 		enum cleanup_prefix_rt_t action;
3817 		unsigned long rt_expires;
3818 
3819 		write_lock_bh(&ifp->idev->lock);
3820 		action = check_cleanup_prefix_route(ifp, &rt_expires);
3821 		write_unlock_bh(&ifp->idev->lock);
3822 
3823 		if (action != CLEANUP_PREFIX_RT_NOP) {
3824 			cleanup_prefix_route(ifp, rt_expires,
3825 				action == CLEANUP_PREFIX_RT_DEL);
3826 		}
3827 	}
3828 
3829 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
3830 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
3831 			valid_lft = prefered_lft = 0;
3832 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
3833 				 !was_managetempaddr, jiffies);
3834 	}
3835 
3836 	addrconf_verify_rtnl();
3837 
3838 	return 0;
3839 }
3840 
3841 static int
3842 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3843 {
3844 	struct net *net = sock_net(skb->sk);
3845 	struct ifaddrmsg *ifm;
3846 	struct nlattr *tb[IFA_MAX+1];
3847 	struct in6_addr *pfx, *peer_pfx;
3848 	struct inet6_ifaddr *ifa;
3849 	struct net_device *dev;
3850 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3851 	u32 ifa_flags;
3852 	int err;
3853 
3854 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3855 	if (err < 0)
3856 		return err;
3857 
3858 	ifm = nlmsg_data(nlh);
3859 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3860 	if (pfx == NULL)
3861 		return -EINVAL;
3862 
3863 	if (tb[IFA_CACHEINFO]) {
3864 		struct ifa_cacheinfo *ci;
3865 
3866 		ci = nla_data(tb[IFA_CACHEINFO]);
3867 		valid_lft = ci->ifa_valid;
3868 		preferred_lft = ci->ifa_prefered;
3869 	} else {
3870 		preferred_lft = INFINITY_LIFE_TIME;
3871 		valid_lft = INFINITY_LIFE_TIME;
3872 	}
3873 
3874 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3875 	if (dev == NULL)
3876 		return -ENODEV;
3877 
3878 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3879 
3880 	/* We ignore other flags so far. */
3881 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3882 		     IFA_F_NOPREFIXROUTE;
3883 
3884 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3885 	if (ifa == NULL) {
3886 		/*
3887 		 * It would be best to check for !NLM_F_CREATE here but
3888 		 * userspace already relies on not having to provide this.
3889 		 */
3890 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
3891 				      ifm->ifa_prefixlen, ifa_flags,
3892 				      preferred_lft, valid_lft);
3893 	}
3894 
3895 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3896 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3897 		err = -EEXIST;
3898 	else
3899 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3900 
3901 	in6_ifa_put(ifa);
3902 
3903 	return err;
3904 }
3905 
3906 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
3907 			  u8 scope, int ifindex)
3908 {
3909 	struct ifaddrmsg *ifm;
3910 
3911 	ifm = nlmsg_data(nlh);
3912 	ifm->ifa_family = AF_INET6;
3913 	ifm->ifa_prefixlen = prefixlen;
3914 	ifm->ifa_flags = flags;
3915 	ifm->ifa_scope = scope;
3916 	ifm->ifa_index = ifindex;
3917 }
3918 
3919 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3920 			 unsigned long tstamp, u32 preferred, u32 valid)
3921 {
3922 	struct ifa_cacheinfo ci;
3923 
3924 	ci.cstamp = cstamp_delta(cstamp);
3925 	ci.tstamp = cstamp_delta(tstamp);
3926 	ci.ifa_prefered = preferred;
3927 	ci.ifa_valid = valid;
3928 
3929 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3930 }
3931 
3932 static inline int rt_scope(int ifa_scope)
3933 {
3934 	if (ifa_scope & IFA_HOST)
3935 		return RT_SCOPE_HOST;
3936 	else if (ifa_scope & IFA_LINK)
3937 		return RT_SCOPE_LINK;
3938 	else if (ifa_scope & IFA_SITE)
3939 		return RT_SCOPE_SITE;
3940 	else
3941 		return RT_SCOPE_UNIVERSE;
3942 }
3943 
3944 static inline int inet6_ifaddr_msgsize(void)
3945 {
3946 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3947 	       + nla_total_size(16) /* IFA_LOCAL */
3948 	       + nla_total_size(16) /* IFA_ADDRESS */
3949 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
3950 	       + nla_total_size(4)  /* IFA_FLAGS */;
3951 }
3952 
3953 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3954 			     u32 portid, u32 seq, int event, unsigned int flags)
3955 {
3956 	struct nlmsghdr  *nlh;
3957 	u32 preferred, valid;
3958 
3959 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3960 	if (nlh == NULL)
3961 		return -EMSGSIZE;
3962 
3963 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3964 		      ifa->idev->dev->ifindex);
3965 
3966 	if (!((ifa->flags&IFA_F_PERMANENT) &&
3967 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
3968 		preferred = ifa->prefered_lft;
3969 		valid = ifa->valid_lft;
3970 		if (preferred != INFINITY_LIFE_TIME) {
3971 			long tval = (jiffies - ifa->tstamp)/HZ;
3972 			if (preferred > tval)
3973 				preferred -= tval;
3974 			else
3975 				preferred = 0;
3976 			if (valid != INFINITY_LIFE_TIME) {
3977 				if (valid > tval)
3978 					valid -= tval;
3979 				else
3980 					valid = 0;
3981 			}
3982 		}
3983 	} else {
3984 		preferred = INFINITY_LIFE_TIME;
3985 		valid = INFINITY_LIFE_TIME;
3986 	}
3987 
3988 	if (!ipv6_addr_any(&ifa->peer_addr)) {
3989 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
3990 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
3991 			goto error;
3992 	} else
3993 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
3994 			goto error;
3995 
3996 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
3997 		goto error;
3998 
3999 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4000 		goto error;
4001 
4002 	return nlmsg_end(skb, nlh);
4003 
4004 error:
4005 	nlmsg_cancel(skb, nlh);
4006 	return -EMSGSIZE;
4007 }
4008 
4009 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4010 				u32 portid, u32 seq, int event, u16 flags)
4011 {
4012 	struct nlmsghdr  *nlh;
4013 	u8 scope = RT_SCOPE_UNIVERSE;
4014 	int ifindex = ifmca->idev->dev->ifindex;
4015 
4016 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4017 		scope = RT_SCOPE_SITE;
4018 
4019 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4020 	if (nlh == NULL)
4021 		return -EMSGSIZE;
4022 
4023 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4024 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
4025 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4026 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4027 		nlmsg_cancel(skb, nlh);
4028 		return -EMSGSIZE;
4029 	}
4030 
4031 	return nlmsg_end(skb, nlh);
4032 }
4033 
4034 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4035 				u32 portid, u32 seq, int event, unsigned int flags)
4036 {
4037 	struct nlmsghdr  *nlh;
4038 	u8 scope = RT_SCOPE_UNIVERSE;
4039 	int ifindex = ifaca->aca_idev->dev->ifindex;
4040 
4041 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4042 		scope = RT_SCOPE_SITE;
4043 
4044 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4045 	if (nlh == NULL)
4046 		return -EMSGSIZE;
4047 
4048 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4049 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
4050 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4051 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4052 		nlmsg_cancel(skb, nlh);
4053 		return -EMSGSIZE;
4054 	}
4055 
4056 	return nlmsg_end(skb, nlh);
4057 }
4058 
4059 enum addr_type_t {
4060 	UNICAST_ADDR,
4061 	MULTICAST_ADDR,
4062 	ANYCAST_ADDR,
4063 };
4064 
4065 /* called with rcu_read_lock() */
4066 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4067 			  struct netlink_callback *cb, enum addr_type_t type,
4068 			  int s_ip_idx, int *p_ip_idx)
4069 {
4070 	struct ifmcaddr6 *ifmca;
4071 	struct ifacaddr6 *ifaca;
4072 	int err = 1;
4073 	int ip_idx = *p_ip_idx;
4074 
4075 	read_lock_bh(&idev->lock);
4076 	switch (type) {
4077 	case UNICAST_ADDR: {
4078 		struct inet6_ifaddr *ifa;
4079 
4080 		/* unicast address incl. temp addr */
4081 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4082 			if (++ip_idx < s_ip_idx)
4083 				continue;
4084 			err = inet6_fill_ifaddr(skb, ifa,
4085 						NETLINK_CB(cb->skb).portid,
4086 						cb->nlh->nlmsg_seq,
4087 						RTM_NEWADDR,
4088 						NLM_F_MULTI);
4089 			if (err <= 0)
4090 				break;
4091 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4092 		}
4093 		break;
4094 	}
4095 	case MULTICAST_ADDR:
4096 		/* multicast address */
4097 		for (ifmca = idev->mc_list; ifmca;
4098 		     ifmca = ifmca->next, ip_idx++) {
4099 			if (ip_idx < s_ip_idx)
4100 				continue;
4101 			err = inet6_fill_ifmcaddr(skb, ifmca,
4102 						  NETLINK_CB(cb->skb).portid,
4103 						  cb->nlh->nlmsg_seq,
4104 						  RTM_GETMULTICAST,
4105 						  NLM_F_MULTI);
4106 			if (err <= 0)
4107 				break;
4108 		}
4109 		break;
4110 	case ANYCAST_ADDR:
4111 		/* anycast address */
4112 		for (ifaca = idev->ac_list; ifaca;
4113 		     ifaca = ifaca->aca_next, ip_idx++) {
4114 			if (ip_idx < s_ip_idx)
4115 				continue;
4116 			err = inet6_fill_ifacaddr(skb, ifaca,
4117 						  NETLINK_CB(cb->skb).portid,
4118 						  cb->nlh->nlmsg_seq,
4119 						  RTM_GETANYCAST,
4120 						  NLM_F_MULTI);
4121 			if (err <= 0)
4122 				break;
4123 		}
4124 		break;
4125 	default:
4126 		break;
4127 	}
4128 	read_unlock_bh(&idev->lock);
4129 	*p_ip_idx = ip_idx;
4130 	return err;
4131 }
4132 
4133 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4134 			   enum addr_type_t type)
4135 {
4136 	struct net *net = sock_net(skb->sk);
4137 	int h, s_h;
4138 	int idx, ip_idx;
4139 	int s_idx, s_ip_idx;
4140 	struct net_device *dev;
4141 	struct inet6_dev *idev;
4142 	struct hlist_head *head;
4143 
4144 	s_h = cb->args[0];
4145 	s_idx = idx = cb->args[1];
4146 	s_ip_idx = ip_idx = cb->args[2];
4147 
4148 	rcu_read_lock();
4149 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4150 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4151 		idx = 0;
4152 		head = &net->dev_index_head[h];
4153 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4154 			if (idx < s_idx)
4155 				goto cont;
4156 			if (h > s_h || idx > s_idx)
4157 				s_ip_idx = 0;
4158 			ip_idx = 0;
4159 			idev = __in6_dev_get(dev);
4160 			if (!idev)
4161 				goto cont;
4162 
4163 			if (in6_dump_addrs(idev, skb, cb, type,
4164 					   s_ip_idx, &ip_idx) <= 0)
4165 				goto done;
4166 cont:
4167 			idx++;
4168 		}
4169 	}
4170 done:
4171 	rcu_read_unlock();
4172 	cb->args[0] = h;
4173 	cb->args[1] = idx;
4174 	cb->args[2] = ip_idx;
4175 
4176 	return skb->len;
4177 }
4178 
4179 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4180 {
4181 	enum addr_type_t type = UNICAST_ADDR;
4182 
4183 	return inet6_dump_addr(skb, cb, type);
4184 }
4185 
4186 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4187 {
4188 	enum addr_type_t type = MULTICAST_ADDR;
4189 
4190 	return inet6_dump_addr(skb, cb, type);
4191 }
4192 
4193 
4194 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4195 {
4196 	enum addr_type_t type = ANYCAST_ADDR;
4197 
4198 	return inet6_dump_addr(skb, cb, type);
4199 }
4200 
4201 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4202 {
4203 	struct net *net = sock_net(in_skb->sk);
4204 	struct ifaddrmsg *ifm;
4205 	struct nlattr *tb[IFA_MAX+1];
4206 	struct in6_addr *addr = NULL, *peer;
4207 	struct net_device *dev = NULL;
4208 	struct inet6_ifaddr *ifa;
4209 	struct sk_buff *skb;
4210 	int err;
4211 
4212 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4213 	if (err < 0)
4214 		goto errout;
4215 
4216 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4217 	if (addr == NULL) {
4218 		err = -EINVAL;
4219 		goto errout;
4220 	}
4221 
4222 	ifm = nlmsg_data(nlh);
4223 	if (ifm->ifa_index)
4224 		dev = __dev_get_by_index(net, ifm->ifa_index);
4225 
4226 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4227 	if (!ifa) {
4228 		err = -EADDRNOTAVAIL;
4229 		goto errout;
4230 	}
4231 
4232 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4233 	if (!skb) {
4234 		err = -ENOBUFS;
4235 		goto errout_ifa;
4236 	}
4237 
4238 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4239 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4240 	if (err < 0) {
4241 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4242 		WARN_ON(err == -EMSGSIZE);
4243 		kfree_skb(skb);
4244 		goto errout_ifa;
4245 	}
4246 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4247 errout_ifa:
4248 	in6_ifa_put(ifa);
4249 errout:
4250 	return err;
4251 }
4252 
4253 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4254 {
4255 	struct sk_buff *skb;
4256 	struct net *net = dev_net(ifa->idev->dev);
4257 	int err = -ENOBUFS;
4258 
4259 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4260 	if (skb == NULL)
4261 		goto errout;
4262 
4263 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4264 	if (err < 0) {
4265 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4266 		WARN_ON(err == -EMSGSIZE);
4267 		kfree_skb(skb);
4268 		goto errout;
4269 	}
4270 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4271 	return;
4272 errout:
4273 	if (err < 0)
4274 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4275 }
4276 
4277 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4278 				__s32 *array, int bytes)
4279 {
4280 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4281 
4282 	memset(array, 0, bytes);
4283 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4284 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4285 	array[DEVCONF_MTU6] = cnf->mtu6;
4286 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4287 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4288 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4289 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4290 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4291 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4292 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4293 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4294 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4295 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4296 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4297 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4298 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4299 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4300 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4301 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4302 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4303 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4304 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4305 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4306 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4307 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4308 #ifdef CONFIG_IPV6_ROUTER_PREF
4309 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4310 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4311 		jiffies_to_msecs(cnf->rtr_probe_interval);
4312 #ifdef CONFIG_IPV6_ROUTE_INFO
4313 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4314 #endif
4315 #endif
4316 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4317 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4318 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4319 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4320 #endif
4321 #ifdef CONFIG_IPV6_MROUTE
4322 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4323 #endif
4324 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4325 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4326 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4327 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4328 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4329 }
4330 
4331 static inline size_t inet6_ifla6_size(void)
4332 {
4333 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4334 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4335 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4336 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4337 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4338 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4339 }
4340 
4341 static inline size_t inet6_if_nlmsg_size(void)
4342 {
4343 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4344 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4345 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4346 	       + nla_total_size(4) /* IFLA_MTU */
4347 	       + nla_total_size(4) /* IFLA_LINK */
4348 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4349 }
4350 
4351 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4352 				      int items, int bytes)
4353 {
4354 	int i;
4355 	int pad = bytes - sizeof(u64) * items;
4356 	BUG_ON(pad < 0);
4357 
4358 	/* Use put_unaligned() because stats may not be aligned for u64. */
4359 	put_unaligned(items, &stats[0]);
4360 	for (i = 1; i < items; i++)
4361 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4362 
4363 	memset(&stats[items], 0, pad);
4364 }
4365 
4366 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4367 				      int items, int bytes, size_t syncpoff)
4368 {
4369 	int i;
4370 	int pad = bytes - sizeof(u64) * items;
4371 	BUG_ON(pad < 0);
4372 
4373 	/* Use put_unaligned() because stats may not be aligned for u64. */
4374 	put_unaligned(items, &stats[0]);
4375 	for (i = 1; i < items; i++)
4376 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4377 
4378 	memset(&stats[items], 0, pad);
4379 }
4380 
4381 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4382 			     int bytes)
4383 {
4384 	switch (attrtype) {
4385 	case IFLA_INET6_STATS:
4386 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4387 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4388 		break;
4389 	case IFLA_INET6_ICMP6STATS:
4390 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4391 		break;
4392 	}
4393 }
4394 
4395 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4396 {
4397 	struct nlattr *nla;
4398 	struct ifla_cacheinfo ci;
4399 
4400 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4401 		goto nla_put_failure;
4402 	ci.max_reasm_len = IPV6_MAXPLEN;
4403 	ci.tstamp = cstamp_delta(idev->tstamp);
4404 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4405 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
4406 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4407 		goto nla_put_failure;
4408 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4409 	if (nla == NULL)
4410 		goto nla_put_failure;
4411 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4412 
4413 	/* XXX - MC not implemented */
4414 
4415 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4416 	if (nla == NULL)
4417 		goto nla_put_failure;
4418 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4419 
4420 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4421 	if (nla == NULL)
4422 		goto nla_put_failure;
4423 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4424 
4425 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4426 	if (nla == NULL)
4427 		goto nla_put_failure;
4428 	read_lock_bh(&idev->lock);
4429 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4430 	read_unlock_bh(&idev->lock);
4431 
4432 	return 0;
4433 
4434 nla_put_failure:
4435 	return -EMSGSIZE;
4436 }
4437 
4438 static size_t inet6_get_link_af_size(const struct net_device *dev)
4439 {
4440 	if (!__in6_dev_get(dev))
4441 		return 0;
4442 
4443 	return inet6_ifla6_size();
4444 }
4445 
4446 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4447 {
4448 	struct inet6_dev *idev = __in6_dev_get(dev);
4449 
4450 	if (!idev)
4451 		return -ENODATA;
4452 
4453 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4454 		return -EMSGSIZE;
4455 
4456 	return 0;
4457 }
4458 
4459 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4460 {
4461 	struct inet6_ifaddr *ifp;
4462 	struct net_device *dev = idev->dev;
4463 	bool update_rs = false;
4464 	struct in6_addr ll_addr;
4465 
4466 	ASSERT_RTNL();
4467 
4468 	if (token == NULL)
4469 		return -EINVAL;
4470 	if (ipv6_addr_any(token))
4471 		return -EINVAL;
4472 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4473 		return -EINVAL;
4474 	if (!ipv6_accept_ra(idev))
4475 		return -EINVAL;
4476 	if (idev->cnf.rtr_solicits <= 0)
4477 		return -EINVAL;
4478 
4479 	write_lock_bh(&idev->lock);
4480 
4481 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4482 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4483 
4484 	write_unlock_bh(&idev->lock);
4485 
4486 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4487 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4488 			     IFA_F_OPTIMISTIC)) {
4489 
4490 		/* If we're not ready, then normal ifup will take care
4491 		 * of this. Otherwise, we need to request our rs here.
4492 		 */
4493 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4494 		update_rs = true;
4495 	}
4496 
4497 	write_lock_bh(&idev->lock);
4498 
4499 	if (update_rs) {
4500 		idev->if_flags |= IF_RS_SENT;
4501 		idev->rs_probes = 1;
4502 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4503 	}
4504 
4505 	/* Well, that's kinda nasty ... */
4506 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4507 		spin_lock(&ifp->lock);
4508 		if (ifp->tokenized) {
4509 			ifp->valid_lft = 0;
4510 			ifp->prefered_lft = 0;
4511 		}
4512 		spin_unlock(&ifp->lock);
4513 	}
4514 
4515 	write_unlock_bh(&idev->lock);
4516 	addrconf_verify_rtnl();
4517 	return 0;
4518 }
4519 
4520 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4521 {
4522 	int err = -EINVAL;
4523 	struct inet6_dev *idev = __in6_dev_get(dev);
4524 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4525 
4526 	if (!idev)
4527 		return -EAFNOSUPPORT;
4528 
4529 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4530 		BUG();
4531 
4532 	if (tb[IFLA_INET6_TOKEN])
4533 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4534 
4535 	return err;
4536 }
4537 
4538 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4539 			     u32 portid, u32 seq, int event, unsigned int flags)
4540 {
4541 	struct net_device *dev = idev->dev;
4542 	struct ifinfomsg *hdr;
4543 	struct nlmsghdr *nlh;
4544 	void *protoinfo;
4545 
4546 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4547 	if (nlh == NULL)
4548 		return -EMSGSIZE;
4549 
4550 	hdr = nlmsg_data(nlh);
4551 	hdr->ifi_family = AF_INET6;
4552 	hdr->__ifi_pad = 0;
4553 	hdr->ifi_type = dev->type;
4554 	hdr->ifi_index = dev->ifindex;
4555 	hdr->ifi_flags = dev_get_flags(dev);
4556 	hdr->ifi_change = 0;
4557 
4558 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4559 	    (dev->addr_len &&
4560 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4561 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4562 	    (dev->ifindex != dev->iflink &&
4563 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4564 		goto nla_put_failure;
4565 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4566 	if (protoinfo == NULL)
4567 		goto nla_put_failure;
4568 
4569 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4570 		goto nla_put_failure;
4571 
4572 	nla_nest_end(skb, protoinfo);
4573 	return nlmsg_end(skb, nlh);
4574 
4575 nla_put_failure:
4576 	nlmsg_cancel(skb, nlh);
4577 	return -EMSGSIZE;
4578 }
4579 
4580 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4581 {
4582 	struct net *net = sock_net(skb->sk);
4583 	int h, s_h;
4584 	int idx = 0, s_idx;
4585 	struct net_device *dev;
4586 	struct inet6_dev *idev;
4587 	struct hlist_head *head;
4588 
4589 	s_h = cb->args[0];
4590 	s_idx = cb->args[1];
4591 
4592 	rcu_read_lock();
4593 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4594 		idx = 0;
4595 		head = &net->dev_index_head[h];
4596 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4597 			if (idx < s_idx)
4598 				goto cont;
4599 			idev = __in6_dev_get(dev);
4600 			if (!idev)
4601 				goto cont;
4602 			if (inet6_fill_ifinfo(skb, idev,
4603 					      NETLINK_CB(cb->skb).portid,
4604 					      cb->nlh->nlmsg_seq,
4605 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4606 				goto out;
4607 cont:
4608 			idx++;
4609 		}
4610 	}
4611 out:
4612 	rcu_read_unlock();
4613 	cb->args[1] = idx;
4614 	cb->args[0] = h;
4615 
4616 	return skb->len;
4617 }
4618 
4619 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4620 {
4621 	struct sk_buff *skb;
4622 	struct net *net = dev_net(idev->dev);
4623 	int err = -ENOBUFS;
4624 
4625 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4626 	if (skb == NULL)
4627 		goto errout;
4628 
4629 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4630 	if (err < 0) {
4631 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4632 		WARN_ON(err == -EMSGSIZE);
4633 		kfree_skb(skb);
4634 		goto errout;
4635 	}
4636 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4637 	return;
4638 errout:
4639 	if (err < 0)
4640 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4641 }
4642 
4643 static inline size_t inet6_prefix_nlmsg_size(void)
4644 {
4645 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4646 	       + nla_total_size(sizeof(struct in6_addr))
4647 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4648 }
4649 
4650 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4651 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4652 			     int event, unsigned int flags)
4653 {
4654 	struct prefixmsg *pmsg;
4655 	struct nlmsghdr *nlh;
4656 	struct prefix_cacheinfo	ci;
4657 
4658 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4659 	if (nlh == NULL)
4660 		return -EMSGSIZE;
4661 
4662 	pmsg = nlmsg_data(nlh);
4663 	pmsg->prefix_family = AF_INET6;
4664 	pmsg->prefix_pad1 = 0;
4665 	pmsg->prefix_pad2 = 0;
4666 	pmsg->prefix_ifindex = idev->dev->ifindex;
4667 	pmsg->prefix_len = pinfo->prefix_len;
4668 	pmsg->prefix_type = pinfo->type;
4669 	pmsg->prefix_pad3 = 0;
4670 	pmsg->prefix_flags = 0;
4671 	if (pinfo->onlink)
4672 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4673 	if (pinfo->autoconf)
4674 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4675 
4676 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4677 		goto nla_put_failure;
4678 	ci.preferred_time = ntohl(pinfo->prefered);
4679 	ci.valid_time = ntohl(pinfo->valid);
4680 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4681 		goto nla_put_failure;
4682 	return nlmsg_end(skb, nlh);
4683 
4684 nla_put_failure:
4685 	nlmsg_cancel(skb, nlh);
4686 	return -EMSGSIZE;
4687 }
4688 
4689 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4690 			 struct prefix_info *pinfo)
4691 {
4692 	struct sk_buff *skb;
4693 	struct net *net = dev_net(idev->dev);
4694 	int err = -ENOBUFS;
4695 
4696 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4697 	if (skb == NULL)
4698 		goto errout;
4699 
4700 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4701 	if (err < 0) {
4702 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4703 		WARN_ON(err == -EMSGSIZE);
4704 		kfree_skb(skb);
4705 		goto errout;
4706 	}
4707 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4708 	return;
4709 errout:
4710 	if (err < 0)
4711 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4712 }
4713 
4714 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4715 {
4716 	struct net *net = dev_net(ifp->idev->dev);
4717 
4718 	if (event)
4719 		ASSERT_RTNL();
4720 
4721 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4722 
4723 	switch (event) {
4724 	case RTM_NEWADDR:
4725 		/*
4726 		 * If the address was optimistic
4727 		 * we inserted the route at the start of
4728 		 * our DAD process, so we don't need
4729 		 * to do it again
4730 		 */
4731 		if (!(ifp->rt->rt6i_node))
4732 			ip6_ins_rt(ifp->rt);
4733 		if (ifp->idev->cnf.forwarding)
4734 			addrconf_join_anycast(ifp);
4735 		if (!ipv6_addr_any(&ifp->peer_addr))
4736 			addrconf_prefix_route(&ifp->peer_addr, 128,
4737 					      ifp->idev->dev, 0, 0);
4738 		break;
4739 	case RTM_DELADDR:
4740 		if (ifp->idev->cnf.forwarding)
4741 			addrconf_leave_anycast(ifp);
4742 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4743 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4744 			struct rt6_info *rt;
4745 			struct net_device *dev = ifp->idev->dev;
4746 
4747 			rt = rt6_lookup(dev_net(dev), &ifp->peer_addr, NULL,
4748 					dev->ifindex, 1);
4749 			if (rt) {
4750 				dst_hold(&rt->dst);
4751 				if (ip6_del_rt(rt))
4752 					dst_free(&rt->dst);
4753 			}
4754 		}
4755 		dst_hold(&ifp->rt->dst);
4756 
4757 		if (ip6_del_rt(ifp->rt))
4758 			dst_free(&ifp->rt->dst);
4759 		break;
4760 	}
4761 	atomic_inc(&net->ipv6.dev_addr_genid);
4762 	rt_genid_bump_ipv6(net);
4763 }
4764 
4765 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4766 {
4767 	rcu_read_lock_bh();
4768 	if (likely(ifp->idev->dead == 0))
4769 		__ipv6_ifa_notify(event, ifp);
4770 	rcu_read_unlock_bh();
4771 }
4772 
4773 #ifdef CONFIG_SYSCTL
4774 
4775 static
4776 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
4777 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4778 {
4779 	int *valp = ctl->data;
4780 	int val = *valp;
4781 	loff_t pos = *ppos;
4782 	struct ctl_table lctl;
4783 	int ret;
4784 
4785 	/*
4786 	 * ctl->data points to idev->cnf.forwarding, we should
4787 	 * not modify it until we get the rtnl lock.
4788 	 */
4789 	lctl = *ctl;
4790 	lctl.data = &val;
4791 
4792 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4793 
4794 	if (write)
4795 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4796 	if (ret)
4797 		*ppos = pos;
4798 	return ret;
4799 }
4800 
4801 static void dev_disable_change(struct inet6_dev *idev)
4802 {
4803 	struct netdev_notifier_info info;
4804 
4805 	if (!idev || !idev->dev)
4806 		return;
4807 
4808 	netdev_notifier_info_init(&info, idev->dev);
4809 	if (idev->cnf.disable_ipv6)
4810 		addrconf_notify(NULL, NETDEV_DOWN, &info);
4811 	else
4812 		addrconf_notify(NULL, NETDEV_UP, &info);
4813 }
4814 
4815 static void addrconf_disable_change(struct net *net, __s32 newf)
4816 {
4817 	struct net_device *dev;
4818 	struct inet6_dev *idev;
4819 
4820 	rcu_read_lock();
4821 	for_each_netdev_rcu(net, dev) {
4822 		idev = __in6_dev_get(dev);
4823 		if (idev) {
4824 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4825 			idev->cnf.disable_ipv6 = newf;
4826 			if (changed)
4827 				dev_disable_change(idev);
4828 		}
4829 	}
4830 	rcu_read_unlock();
4831 }
4832 
4833 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4834 {
4835 	struct net *net;
4836 	int old;
4837 
4838 	if (!rtnl_trylock())
4839 		return restart_syscall();
4840 
4841 	net = (struct net *)table->extra2;
4842 	old = *p;
4843 	*p = newf;
4844 
4845 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4846 		rtnl_unlock();
4847 		return 0;
4848 	}
4849 
4850 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4851 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4852 		addrconf_disable_change(net, newf);
4853 	} else if ((!newf) ^ (!old))
4854 		dev_disable_change((struct inet6_dev *)table->extra1);
4855 
4856 	rtnl_unlock();
4857 	return 0;
4858 }
4859 
4860 static
4861 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
4862 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4863 {
4864 	int *valp = ctl->data;
4865 	int val = *valp;
4866 	loff_t pos = *ppos;
4867 	struct ctl_table lctl;
4868 	int ret;
4869 
4870 	/*
4871 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4872 	 * not modify it until we get the rtnl lock.
4873 	 */
4874 	lctl = *ctl;
4875 	lctl.data = &val;
4876 
4877 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4878 
4879 	if (write)
4880 		ret = addrconf_disable_ipv6(ctl, valp, val);
4881 	if (ret)
4882 		*ppos = pos;
4883 	return ret;
4884 }
4885 
4886 static
4887 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
4888 			      void __user *buffer, size_t *lenp, loff_t *ppos)
4889 {
4890 	int *valp = ctl->data;
4891 	int ret;
4892 	int old, new;
4893 
4894 	old = *valp;
4895 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
4896 	new = *valp;
4897 
4898 	if (write && old != new) {
4899 		struct net *net = ctl->extra2;
4900 
4901 		if (!rtnl_trylock())
4902 			return restart_syscall();
4903 
4904 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
4905 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4906 						     NETCONFA_IFINDEX_DEFAULT,
4907 						     net->ipv6.devconf_dflt);
4908 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
4909 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4910 						     NETCONFA_IFINDEX_ALL,
4911 						     net->ipv6.devconf_all);
4912 		else {
4913 			struct inet6_dev *idev = ctl->extra1;
4914 
4915 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4916 						     idev->dev->ifindex,
4917 						     &idev->cnf);
4918 		}
4919 		rtnl_unlock();
4920 	}
4921 
4922 	return ret;
4923 }
4924 
4925 
4926 static struct addrconf_sysctl_table
4927 {
4928 	struct ctl_table_header *sysctl_header;
4929 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
4930 } addrconf_sysctl __read_mostly = {
4931 	.sysctl_header = NULL,
4932 	.addrconf_vars = {
4933 		{
4934 			.procname	= "forwarding",
4935 			.data		= &ipv6_devconf.forwarding,
4936 			.maxlen		= sizeof(int),
4937 			.mode		= 0644,
4938 			.proc_handler	= addrconf_sysctl_forward,
4939 		},
4940 		{
4941 			.procname	= "hop_limit",
4942 			.data		= &ipv6_devconf.hop_limit,
4943 			.maxlen		= sizeof(int),
4944 			.mode		= 0644,
4945 			.proc_handler	= proc_dointvec,
4946 		},
4947 		{
4948 			.procname	= "mtu",
4949 			.data		= &ipv6_devconf.mtu6,
4950 			.maxlen		= sizeof(int),
4951 			.mode		= 0644,
4952 			.proc_handler	= proc_dointvec,
4953 		},
4954 		{
4955 			.procname	= "accept_ra",
4956 			.data		= &ipv6_devconf.accept_ra,
4957 			.maxlen		= sizeof(int),
4958 			.mode		= 0644,
4959 			.proc_handler	= proc_dointvec,
4960 		},
4961 		{
4962 			.procname	= "accept_redirects",
4963 			.data		= &ipv6_devconf.accept_redirects,
4964 			.maxlen		= sizeof(int),
4965 			.mode		= 0644,
4966 			.proc_handler	= proc_dointvec,
4967 		},
4968 		{
4969 			.procname	= "autoconf",
4970 			.data		= &ipv6_devconf.autoconf,
4971 			.maxlen		= sizeof(int),
4972 			.mode		= 0644,
4973 			.proc_handler	= proc_dointvec,
4974 		},
4975 		{
4976 			.procname	= "dad_transmits",
4977 			.data		= &ipv6_devconf.dad_transmits,
4978 			.maxlen		= sizeof(int),
4979 			.mode		= 0644,
4980 			.proc_handler	= proc_dointvec,
4981 		},
4982 		{
4983 			.procname	= "router_solicitations",
4984 			.data		= &ipv6_devconf.rtr_solicits,
4985 			.maxlen		= sizeof(int),
4986 			.mode		= 0644,
4987 			.proc_handler	= proc_dointvec,
4988 		},
4989 		{
4990 			.procname	= "router_solicitation_interval",
4991 			.data		= &ipv6_devconf.rtr_solicit_interval,
4992 			.maxlen		= sizeof(int),
4993 			.mode		= 0644,
4994 			.proc_handler	= proc_dointvec_jiffies,
4995 		},
4996 		{
4997 			.procname	= "router_solicitation_delay",
4998 			.data		= &ipv6_devconf.rtr_solicit_delay,
4999 			.maxlen		= sizeof(int),
5000 			.mode		= 0644,
5001 			.proc_handler	= proc_dointvec_jiffies,
5002 		},
5003 		{
5004 			.procname	= "force_mld_version",
5005 			.data		= &ipv6_devconf.force_mld_version,
5006 			.maxlen		= sizeof(int),
5007 			.mode		= 0644,
5008 			.proc_handler	= proc_dointvec,
5009 		},
5010 		{
5011 			.procname	= "mldv1_unsolicited_report_interval",
5012 			.data		=
5013 				&ipv6_devconf.mldv1_unsolicited_report_interval,
5014 			.maxlen		= sizeof(int),
5015 			.mode		= 0644,
5016 			.proc_handler	= proc_dointvec_ms_jiffies,
5017 		},
5018 		{
5019 			.procname	= "mldv2_unsolicited_report_interval",
5020 			.data		=
5021 				&ipv6_devconf.mldv2_unsolicited_report_interval,
5022 			.maxlen		= sizeof(int),
5023 			.mode		= 0644,
5024 			.proc_handler	= proc_dointvec_ms_jiffies,
5025 		},
5026 		{
5027 			.procname	= "use_tempaddr",
5028 			.data		= &ipv6_devconf.use_tempaddr,
5029 			.maxlen		= sizeof(int),
5030 			.mode		= 0644,
5031 			.proc_handler	= proc_dointvec,
5032 		},
5033 		{
5034 			.procname	= "temp_valid_lft",
5035 			.data		= &ipv6_devconf.temp_valid_lft,
5036 			.maxlen		= sizeof(int),
5037 			.mode		= 0644,
5038 			.proc_handler	= proc_dointvec,
5039 		},
5040 		{
5041 			.procname	= "temp_prefered_lft",
5042 			.data		= &ipv6_devconf.temp_prefered_lft,
5043 			.maxlen		= sizeof(int),
5044 			.mode		= 0644,
5045 			.proc_handler	= proc_dointvec,
5046 		},
5047 		{
5048 			.procname	= "regen_max_retry",
5049 			.data		= &ipv6_devconf.regen_max_retry,
5050 			.maxlen		= sizeof(int),
5051 			.mode		= 0644,
5052 			.proc_handler	= proc_dointvec,
5053 		},
5054 		{
5055 			.procname	= "max_desync_factor",
5056 			.data		= &ipv6_devconf.max_desync_factor,
5057 			.maxlen		= sizeof(int),
5058 			.mode		= 0644,
5059 			.proc_handler	= proc_dointvec,
5060 		},
5061 		{
5062 			.procname	= "max_addresses",
5063 			.data		= &ipv6_devconf.max_addresses,
5064 			.maxlen		= sizeof(int),
5065 			.mode		= 0644,
5066 			.proc_handler	= proc_dointvec,
5067 		},
5068 		{
5069 			.procname	= "accept_ra_defrtr",
5070 			.data		= &ipv6_devconf.accept_ra_defrtr,
5071 			.maxlen		= sizeof(int),
5072 			.mode		= 0644,
5073 			.proc_handler	= proc_dointvec,
5074 		},
5075 		{
5076 			.procname	= "accept_ra_pinfo",
5077 			.data		= &ipv6_devconf.accept_ra_pinfo,
5078 			.maxlen		= sizeof(int),
5079 			.mode		= 0644,
5080 			.proc_handler	= proc_dointvec,
5081 		},
5082 #ifdef CONFIG_IPV6_ROUTER_PREF
5083 		{
5084 			.procname	= "accept_ra_rtr_pref",
5085 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
5086 			.maxlen		= sizeof(int),
5087 			.mode		= 0644,
5088 			.proc_handler	= proc_dointvec,
5089 		},
5090 		{
5091 			.procname	= "router_probe_interval",
5092 			.data		= &ipv6_devconf.rtr_probe_interval,
5093 			.maxlen		= sizeof(int),
5094 			.mode		= 0644,
5095 			.proc_handler	= proc_dointvec_jiffies,
5096 		},
5097 #ifdef CONFIG_IPV6_ROUTE_INFO
5098 		{
5099 			.procname	= "accept_ra_rt_info_max_plen",
5100 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5101 			.maxlen		= sizeof(int),
5102 			.mode		= 0644,
5103 			.proc_handler	= proc_dointvec,
5104 		},
5105 #endif
5106 #endif
5107 		{
5108 			.procname	= "proxy_ndp",
5109 			.data		= &ipv6_devconf.proxy_ndp,
5110 			.maxlen		= sizeof(int),
5111 			.mode		= 0644,
5112 			.proc_handler	= addrconf_sysctl_proxy_ndp,
5113 		},
5114 		{
5115 			.procname	= "accept_source_route",
5116 			.data		= &ipv6_devconf.accept_source_route,
5117 			.maxlen		= sizeof(int),
5118 			.mode		= 0644,
5119 			.proc_handler	= proc_dointvec,
5120 		},
5121 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5122 		{
5123 			.procname       = "optimistic_dad",
5124 			.data           = &ipv6_devconf.optimistic_dad,
5125 			.maxlen         = sizeof(int),
5126 			.mode           = 0644,
5127 			.proc_handler   = proc_dointvec,
5128 
5129 		},
5130 #endif
5131 #ifdef CONFIG_IPV6_MROUTE
5132 		{
5133 			.procname	= "mc_forwarding",
5134 			.data		= &ipv6_devconf.mc_forwarding,
5135 			.maxlen		= sizeof(int),
5136 			.mode		= 0444,
5137 			.proc_handler	= proc_dointvec,
5138 		},
5139 #endif
5140 		{
5141 			.procname	= "disable_ipv6",
5142 			.data		= &ipv6_devconf.disable_ipv6,
5143 			.maxlen		= sizeof(int),
5144 			.mode		= 0644,
5145 			.proc_handler	= addrconf_sysctl_disable,
5146 		},
5147 		{
5148 			.procname	= "accept_dad",
5149 			.data		= &ipv6_devconf.accept_dad,
5150 			.maxlen		= sizeof(int),
5151 			.mode		= 0644,
5152 			.proc_handler	= proc_dointvec,
5153 		},
5154 		{
5155 			.procname       = "force_tllao",
5156 			.data           = &ipv6_devconf.force_tllao,
5157 			.maxlen         = sizeof(int),
5158 			.mode           = 0644,
5159 			.proc_handler   = proc_dointvec
5160 		},
5161 		{
5162 			.procname       = "ndisc_notify",
5163 			.data           = &ipv6_devconf.ndisc_notify,
5164 			.maxlen         = sizeof(int),
5165 			.mode           = 0644,
5166 			.proc_handler   = proc_dointvec
5167 		},
5168 		{
5169 			.procname	= "suppress_frag_ndisc",
5170 			.data		= &ipv6_devconf.suppress_frag_ndisc,
5171 			.maxlen		= sizeof(int),
5172 			.mode		= 0644,
5173 			.proc_handler	= proc_dointvec
5174 		},
5175 		{
5176 			/* sentinel */
5177 		}
5178 	},
5179 };
5180 
5181 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
5182 		struct inet6_dev *idev, struct ipv6_devconf *p)
5183 {
5184 	int i;
5185 	struct addrconf_sysctl_table *t;
5186 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
5187 
5188 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
5189 	if (t == NULL)
5190 		goto out;
5191 
5192 	for (i = 0; t->addrconf_vars[i].data; i++) {
5193 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
5194 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
5195 		t->addrconf_vars[i].extra2 = net;
5196 	}
5197 
5198 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
5199 
5200 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
5201 	if (t->sysctl_header == NULL)
5202 		goto free;
5203 
5204 	p->sysctl = t;
5205 	return 0;
5206 
5207 free:
5208 	kfree(t);
5209 out:
5210 	return -ENOBUFS;
5211 }
5212 
5213 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5214 {
5215 	struct addrconf_sysctl_table *t;
5216 
5217 	if (p->sysctl == NULL)
5218 		return;
5219 
5220 	t = p->sysctl;
5221 	p->sysctl = NULL;
5222 	unregister_net_sysctl_table(t->sysctl_header);
5223 	kfree(t);
5224 }
5225 
5226 static void addrconf_sysctl_register(struct inet6_dev *idev)
5227 {
5228 	neigh_sysctl_register(idev->dev, idev->nd_parms,
5229 			      &ndisc_ifinfo_sysctl_change);
5230 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5231 					idev, &idev->cnf);
5232 }
5233 
5234 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5235 {
5236 	__addrconf_sysctl_unregister(&idev->cnf);
5237 	neigh_sysctl_unregister(idev->nd_parms);
5238 }
5239 
5240 
5241 #endif
5242 
5243 static int __net_init addrconf_init_net(struct net *net)
5244 {
5245 	int err = -ENOMEM;
5246 	struct ipv6_devconf *all, *dflt;
5247 
5248 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5249 	if (all == NULL)
5250 		goto err_alloc_all;
5251 
5252 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5253 	if (dflt == NULL)
5254 		goto err_alloc_dflt;
5255 
5256 	/* these will be inherited by all namespaces */
5257 	dflt->autoconf = ipv6_defaults.autoconf;
5258 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5259 
5260 	net->ipv6.devconf_all = all;
5261 	net->ipv6.devconf_dflt = dflt;
5262 
5263 #ifdef CONFIG_SYSCTL
5264 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5265 	if (err < 0)
5266 		goto err_reg_all;
5267 
5268 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5269 	if (err < 0)
5270 		goto err_reg_dflt;
5271 #endif
5272 	return 0;
5273 
5274 #ifdef CONFIG_SYSCTL
5275 err_reg_dflt:
5276 	__addrconf_sysctl_unregister(all);
5277 err_reg_all:
5278 	kfree(dflt);
5279 #endif
5280 err_alloc_dflt:
5281 	kfree(all);
5282 err_alloc_all:
5283 	return err;
5284 }
5285 
5286 static void __net_exit addrconf_exit_net(struct net *net)
5287 {
5288 #ifdef CONFIG_SYSCTL
5289 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5290 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5291 #endif
5292 	if (!net_eq(net, &init_net)) {
5293 		kfree(net->ipv6.devconf_dflt);
5294 		kfree(net->ipv6.devconf_all);
5295 	}
5296 }
5297 
5298 static struct pernet_operations addrconf_ops = {
5299 	.init = addrconf_init_net,
5300 	.exit = addrconf_exit_net,
5301 };
5302 
5303 static struct rtnl_af_ops inet6_ops = {
5304 	.family		  = AF_INET6,
5305 	.fill_link_af	  = inet6_fill_link_af,
5306 	.get_link_af_size = inet6_get_link_af_size,
5307 	.set_link_af	  = inet6_set_link_af,
5308 };
5309 
5310 /*
5311  *	Init / cleanup code
5312  */
5313 
5314 int __init addrconf_init(void)
5315 {
5316 	int i, err;
5317 
5318 	err = ipv6_addr_label_init();
5319 	if (err < 0) {
5320 		pr_crit("%s: cannot initialize default policy table: %d\n",
5321 			__func__, err);
5322 		goto out;
5323 	}
5324 
5325 	err = register_pernet_subsys(&addrconf_ops);
5326 	if (err < 0)
5327 		goto out_addrlabel;
5328 
5329 	addrconf_wq = create_workqueue("ipv6_addrconf");
5330 	if (!addrconf_wq) {
5331 		err = -ENOMEM;
5332 		goto out_nowq;
5333 	}
5334 
5335 	/* The addrconf netdev notifier requires that loopback_dev
5336 	 * has it's ipv6 private information allocated and setup
5337 	 * before it can bring up and give link-local addresses
5338 	 * to other devices which are up.
5339 	 *
5340 	 * Unfortunately, loopback_dev is not necessarily the first
5341 	 * entry in the global dev_base list of net devices.  In fact,
5342 	 * it is likely to be the very last entry on that list.
5343 	 * So this causes the notifier registry below to try and
5344 	 * give link-local addresses to all devices besides loopback_dev
5345 	 * first, then loopback_dev, which cases all the non-loopback_dev
5346 	 * devices to fail to get a link-local address.
5347 	 *
5348 	 * So, as a temporary fix, allocate the ipv6 structure for
5349 	 * loopback_dev first by hand.
5350 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5351 	 * device and it being up should be removed.
5352 	 */
5353 	rtnl_lock();
5354 	if (!ipv6_add_dev(init_net.loopback_dev))
5355 		err = -ENOMEM;
5356 	rtnl_unlock();
5357 	if (err)
5358 		goto errlo;
5359 
5360 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5361 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5362 
5363 	register_netdevice_notifier(&ipv6_dev_notf);
5364 
5365 	addrconf_verify();
5366 
5367 	rtnl_af_register(&inet6_ops);
5368 
5369 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5370 			      NULL);
5371 	if (err < 0)
5372 		goto errout;
5373 
5374 	/* Only the first call to __rtnl_register can fail */
5375 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5376 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5377 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5378 			inet6_dump_ifaddr, NULL);
5379 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5380 			inet6_dump_ifmcaddr, NULL);
5381 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5382 			inet6_dump_ifacaddr, NULL);
5383 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5384 			inet6_netconf_dump_devconf, NULL);
5385 
5386 	ipv6_addr_label_rtnl_register();
5387 
5388 	return 0;
5389 errout:
5390 	rtnl_af_unregister(&inet6_ops);
5391 	unregister_netdevice_notifier(&ipv6_dev_notf);
5392 errlo:
5393 	destroy_workqueue(addrconf_wq);
5394 out_nowq:
5395 	unregister_pernet_subsys(&addrconf_ops);
5396 out_addrlabel:
5397 	ipv6_addr_label_cleanup();
5398 out:
5399 	return err;
5400 }
5401 
5402 void addrconf_cleanup(void)
5403 {
5404 	struct net_device *dev;
5405 	int i;
5406 
5407 	unregister_netdevice_notifier(&ipv6_dev_notf);
5408 	unregister_pernet_subsys(&addrconf_ops);
5409 	ipv6_addr_label_cleanup();
5410 
5411 	rtnl_lock();
5412 
5413 	__rtnl_af_unregister(&inet6_ops);
5414 
5415 	/* clean dev list */
5416 	for_each_netdev(&init_net, dev) {
5417 		if (__in6_dev_get(dev) == NULL)
5418 			continue;
5419 		addrconf_ifdown(dev, 1);
5420 	}
5421 	addrconf_ifdown(init_net.loopback_dev, 2);
5422 
5423 	/*
5424 	 *	Check hash table.
5425 	 */
5426 	spin_lock_bh(&addrconf_hash_lock);
5427 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5428 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5429 	spin_unlock_bh(&addrconf_hash_lock);
5430 	cancel_delayed_work(&addr_chk_work);
5431 	rtnl_unlock();
5432 
5433 	destroy_workqueue(addrconf_wq);
5434 }
5435