xref: /openbmc/linux/net/ipv6/addrconf.c (revision 8a26af30)
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 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
279 	if (!idev->stats.ipv6)
280 		goto err_ip;
281 
282 	for_each_possible_cpu(i) {
283 		struct ipstats_mib *addrconf_stats;
284 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
285 		u64_stats_init(&addrconf_stats->syncp);
286 	}
287 
288 
289 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
290 					GFP_KERNEL);
291 	if (!idev->stats.icmpv6dev)
292 		goto err_icmp;
293 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
294 					   GFP_KERNEL);
295 	if (!idev->stats.icmpv6msgdev)
296 		goto err_icmpmsg;
297 
298 	return 0;
299 
300 err_icmpmsg:
301 	kfree(idev->stats.icmpv6dev);
302 err_icmp:
303 	free_percpu(idev->stats.ipv6);
304 err_ip:
305 	return -ENOMEM;
306 }
307 
308 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
309 {
310 	struct inet6_dev *ndev;
311 
312 	ASSERT_RTNL();
313 
314 	if (dev->mtu < IPV6_MIN_MTU)
315 		return NULL;
316 
317 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
318 
319 	if (ndev == NULL)
320 		return NULL;
321 
322 	rwlock_init(&ndev->lock);
323 	ndev->dev = dev;
324 	INIT_LIST_HEAD(&ndev->addr_list);
325 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
326 		    (unsigned long)ndev);
327 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
328 	ndev->cnf.mtu6 = dev->mtu;
329 	ndev->cnf.sysctl = NULL;
330 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
331 	if (ndev->nd_parms == NULL) {
332 		kfree(ndev);
333 		return NULL;
334 	}
335 	if (ndev->cnf.forwarding)
336 		dev_disable_lro(dev);
337 	/* We refer to the device */
338 	dev_hold(dev);
339 
340 	if (snmp6_alloc_dev(ndev) < 0) {
341 		ADBG(KERN_WARNING
342 			"%s: cannot allocate memory for statistics; dev=%s.\n",
343 			__func__, dev->name);
344 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
345 		dev_put(dev);
346 		kfree(ndev);
347 		return NULL;
348 	}
349 
350 	if (snmp6_register_dev(ndev) < 0) {
351 		ADBG(KERN_WARNING
352 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
353 			__func__, dev->name);
354 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
355 		ndev->dead = 1;
356 		in6_dev_finish_destroy(ndev);
357 		return NULL;
358 	}
359 
360 	/* One reference from device.  We must do this before
361 	 * we invoke __ipv6_regen_rndid().
362 	 */
363 	in6_dev_hold(ndev);
364 
365 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
366 		ndev->cnf.accept_dad = -1;
367 
368 #if IS_ENABLED(CONFIG_IPV6_SIT)
369 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
370 		pr_info("%s: Disabled Multicast RS\n", dev->name);
371 		ndev->cnf.rtr_solicits = 0;
372 	}
373 #endif
374 
375 	INIT_LIST_HEAD(&ndev->tempaddr_list);
376 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
377 	if ((dev->flags&IFF_LOOPBACK) ||
378 	    dev->type == ARPHRD_TUNNEL ||
379 	    dev->type == ARPHRD_TUNNEL6 ||
380 	    dev->type == ARPHRD_SIT ||
381 	    dev->type == ARPHRD_NONE) {
382 		ndev->cnf.use_tempaddr = -1;
383 	} else {
384 		in6_dev_hold(ndev);
385 		ipv6_regen_rndid((unsigned long) ndev);
386 	}
387 
388 	ndev->token = in6addr_any;
389 
390 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
391 		ndev->if_flags |= IF_READY;
392 
393 	ipv6_mc_init_dev(ndev);
394 	ndev->tstamp = jiffies;
395 	addrconf_sysctl_register(ndev);
396 	/* protected by rtnl_lock */
397 	rcu_assign_pointer(dev->ip6_ptr, ndev);
398 
399 	/* Join interface-local all-node multicast group */
400 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
401 
402 	/* Join all-node multicast group */
403 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
404 
405 	/* Join all-router multicast group if forwarding is set */
406 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
407 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
408 
409 	return ndev;
410 }
411 
412 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
413 {
414 	struct inet6_dev *idev;
415 
416 	ASSERT_RTNL();
417 
418 	idev = __in6_dev_get(dev);
419 	if (!idev) {
420 		idev = ipv6_add_dev(dev);
421 		if (!idev)
422 			return NULL;
423 	}
424 
425 	if (dev->flags&IFF_UP)
426 		ipv6_mc_up(idev);
427 	return idev;
428 }
429 
430 static int inet6_netconf_msgsize_devconf(int type)
431 {
432 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
433 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
434 
435 	/* type -1 is used for ALL */
436 	if (type == -1 || type == NETCONFA_FORWARDING)
437 		size += nla_total_size(4);
438 #ifdef CONFIG_IPV6_MROUTE
439 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
440 		size += nla_total_size(4);
441 #endif
442 	if (type == -1 || type == NETCONFA_PROXY_NEIGH)
443 		size += nla_total_size(4);
444 
445 	return size;
446 }
447 
448 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
449 				      struct ipv6_devconf *devconf, u32 portid,
450 				      u32 seq, int event, unsigned int flags,
451 				      int type)
452 {
453 	struct nlmsghdr  *nlh;
454 	struct netconfmsg *ncm;
455 
456 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
457 			flags);
458 	if (nlh == NULL)
459 		return -EMSGSIZE;
460 
461 	ncm = nlmsg_data(nlh);
462 	ncm->ncm_family = AF_INET6;
463 
464 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
465 		goto nla_put_failure;
466 
467 	/* type -1 is used for ALL */
468 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
469 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
470 		goto nla_put_failure;
471 #ifdef CONFIG_IPV6_MROUTE
472 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
473 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
474 			devconf->mc_forwarding) < 0)
475 		goto nla_put_failure;
476 #endif
477 	if ((type == -1 || type == NETCONFA_PROXY_NEIGH) &&
478 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
479 		goto nla_put_failure;
480 
481 	return nlmsg_end(skb, nlh);
482 
483 nla_put_failure:
484 	nlmsg_cancel(skb, nlh);
485 	return -EMSGSIZE;
486 }
487 
488 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
489 				  struct ipv6_devconf *devconf)
490 {
491 	struct sk_buff *skb;
492 	int err = -ENOBUFS;
493 
494 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
495 	if (skb == NULL)
496 		goto errout;
497 
498 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
499 					 RTM_NEWNETCONF, 0, type);
500 	if (err < 0) {
501 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
502 		WARN_ON(err == -EMSGSIZE);
503 		kfree_skb(skb);
504 		goto errout;
505 	}
506 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
507 	return;
508 errout:
509 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
510 }
511 
512 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
513 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
514 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
515 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
516 };
517 
518 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
519 				     struct nlmsghdr *nlh)
520 {
521 	struct net *net = sock_net(in_skb->sk);
522 	struct nlattr *tb[NETCONFA_MAX+1];
523 	struct netconfmsg *ncm;
524 	struct sk_buff *skb;
525 	struct ipv6_devconf *devconf;
526 	struct inet6_dev *in6_dev;
527 	struct net_device *dev;
528 	int ifindex;
529 	int err;
530 
531 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
532 			  devconf_ipv6_policy);
533 	if (err < 0)
534 		goto errout;
535 
536 	err = EINVAL;
537 	if (!tb[NETCONFA_IFINDEX])
538 		goto errout;
539 
540 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
541 	switch (ifindex) {
542 	case NETCONFA_IFINDEX_ALL:
543 		devconf = net->ipv6.devconf_all;
544 		break;
545 	case NETCONFA_IFINDEX_DEFAULT:
546 		devconf = net->ipv6.devconf_dflt;
547 		break;
548 	default:
549 		dev = __dev_get_by_index(net, ifindex);
550 		if (dev == NULL)
551 			goto errout;
552 		in6_dev = __in6_dev_get(dev);
553 		if (in6_dev == NULL)
554 			goto errout;
555 		devconf = &in6_dev->cnf;
556 		break;
557 	}
558 
559 	err = -ENOBUFS;
560 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
561 	if (skb == NULL)
562 		goto errout;
563 
564 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
565 					 NETLINK_CB(in_skb).portid,
566 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
567 					 -1);
568 	if (err < 0) {
569 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
570 		WARN_ON(err == -EMSGSIZE);
571 		kfree_skb(skb);
572 		goto errout;
573 	}
574 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
575 errout:
576 	return err;
577 }
578 
579 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
580 				      struct netlink_callback *cb)
581 {
582 	struct net *net = sock_net(skb->sk);
583 	int h, s_h;
584 	int idx, s_idx;
585 	struct net_device *dev;
586 	struct inet6_dev *idev;
587 	struct hlist_head *head;
588 
589 	s_h = cb->args[0];
590 	s_idx = idx = cb->args[1];
591 
592 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
593 		idx = 0;
594 		head = &net->dev_index_head[h];
595 		rcu_read_lock();
596 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
597 			  net->dev_base_seq;
598 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
599 			if (idx < s_idx)
600 				goto cont;
601 			idev = __in6_dev_get(dev);
602 			if (!idev)
603 				goto cont;
604 
605 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
606 						       &idev->cnf,
607 						       NETLINK_CB(cb->skb).portid,
608 						       cb->nlh->nlmsg_seq,
609 						       RTM_NEWNETCONF,
610 						       NLM_F_MULTI,
611 						       -1) <= 0) {
612 				rcu_read_unlock();
613 				goto done;
614 			}
615 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
616 cont:
617 			idx++;
618 		}
619 		rcu_read_unlock();
620 	}
621 	if (h == NETDEV_HASHENTRIES) {
622 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
623 					       net->ipv6.devconf_all,
624 					       NETLINK_CB(cb->skb).portid,
625 					       cb->nlh->nlmsg_seq,
626 					       RTM_NEWNETCONF, NLM_F_MULTI,
627 					       -1) <= 0)
628 			goto done;
629 		else
630 			h++;
631 	}
632 	if (h == NETDEV_HASHENTRIES + 1) {
633 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
634 					       net->ipv6.devconf_dflt,
635 					       NETLINK_CB(cb->skb).portid,
636 					       cb->nlh->nlmsg_seq,
637 					       RTM_NEWNETCONF, NLM_F_MULTI,
638 					       -1) <= 0)
639 			goto done;
640 		else
641 			h++;
642 	}
643 done:
644 	cb->args[0] = h;
645 	cb->args[1] = idx;
646 
647 	return skb->len;
648 }
649 
650 #ifdef CONFIG_SYSCTL
651 static void dev_forward_change(struct inet6_dev *idev)
652 {
653 	struct net_device *dev;
654 	struct inet6_ifaddr *ifa;
655 
656 	if (!idev)
657 		return;
658 	dev = idev->dev;
659 	if (idev->cnf.forwarding)
660 		dev_disable_lro(dev);
661 	if (dev->flags & IFF_MULTICAST) {
662 		if (idev->cnf.forwarding) {
663 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
664 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
665 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
666 		} else {
667 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
668 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
669 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
670 		}
671 	}
672 
673 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
674 		if (ifa->flags&IFA_F_TENTATIVE)
675 			continue;
676 		if (idev->cnf.forwarding)
677 			addrconf_join_anycast(ifa);
678 		else
679 			addrconf_leave_anycast(ifa);
680 	}
681 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
682 				     dev->ifindex, &idev->cnf);
683 }
684 
685 
686 static void addrconf_forward_change(struct net *net, __s32 newf)
687 {
688 	struct net_device *dev;
689 	struct inet6_dev *idev;
690 
691 	for_each_netdev(net, dev) {
692 		idev = __in6_dev_get(dev);
693 		if (idev) {
694 			int changed = (!idev->cnf.forwarding) ^ (!newf);
695 			idev->cnf.forwarding = newf;
696 			if (changed)
697 				dev_forward_change(idev);
698 		}
699 	}
700 }
701 
702 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
703 {
704 	struct net *net;
705 	int old;
706 
707 	if (!rtnl_trylock())
708 		return restart_syscall();
709 
710 	net = (struct net *)table->extra2;
711 	old = *p;
712 	*p = newf;
713 
714 	if (p == &net->ipv6.devconf_dflt->forwarding) {
715 		if ((!newf) ^ (!old))
716 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
717 						     NETCONFA_IFINDEX_DEFAULT,
718 						     net->ipv6.devconf_dflt);
719 		rtnl_unlock();
720 		return 0;
721 	}
722 
723 	if (p == &net->ipv6.devconf_all->forwarding) {
724 		net->ipv6.devconf_dflt->forwarding = newf;
725 		addrconf_forward_change(net, newf);
726 		if ((!newf) ^ (!old))
727 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
728 						     NETCONFA_IFINDEX_ALL,
729 						     net->ipv6.devconf_all);
730 	} else if ((!newf) ^ (!old))
731 		dev_forward_change((struct inet6_dev *)table->extra1);
732 	rtnl_unlock();
733 
734 	if (newf)
735 		rt6_purge_dflt_routers(net);
736 	return 1;
737 }
738 #endif
739 
740 /* Nobody refers to this ifaddr, destroy it */
741 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
742 {
743 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
744 
745 #ifdef NET_REFCNT_DEBUG
746 	pr_debug("%s\n", __func__);
747 #endif
748 
749 	in6_dev_put(ifp->idev);
750 
751 	if (cancel_delayed_work(&ifp->dad_work))
752 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
753 			  ifp);
754 
755 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
756 		pr_warn("Freeing alive inet6 address %p\n", ifp);
757 		return;
758 	}
759 	ip6_rt_put(ifp->rt);
760 
761 	kfree_rcu(ifp, rcu);
762 }
763 
764 static void
765 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
766 {
767 	struct list_head *p;
768 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
769 
770 	/*
771 	 * Each device address list is sorted in order of scope -
772 	 * global before linklocal.
773 	 */
774 	list_for_each(p, &idev->addr_list) {
775 		struct inet6_ifaddr *ifa
776 			= list_entry(p, struct inet6_ifaddr, if_list);
777 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
778 			break;
779 	}
780 
781 	list_add_tail(&ifp->if_list, p);
782 }
783 
784 static u32 inet6_addr_hash(const struct in6_addr *addr)
785 {
786 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
787 }
788 
789 /* On success it returns ifp with increased reference count */
790 
791 static struct inet6_ifaddr *
792 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
793 	      const struct in6_addr *peer_addr, int pfxlen,
794 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
795 {
796 	struct inet6_ifaddr *ifa = NULL;
797 	struct rt6_info *rt;
798 	unsigned int hash;
799 	int err = 0;
800 	int addr_type = ipv6_addr_type(addr);
801 
802 	if (addr_type == IPV6_ADDR_ANY ||
803 	    addr_type & IPV6_ADDR_MULTICAST ||
804 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
805 	     addr_type & IPV6_ADDR_LOOPBACK))
806 		return ERR_PTR(-EADDRNOTAVAIL);
807 
808 	rcu_read_lock_bh();
809 	if (idev->dead) {
810 		err = -ENODEV;			/*XXX*/
811 		goto out2;
812 	}
813 
814 	if (idev->cnf.disable_ipv6) {
815 		err = -EACCES;
816 		goto out2;
817 	}
818 
819 	spin_lock(&addrconf_hash_lock);
820 
821 	/* Ignore adding duplicate addresses on an interface */
822 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
823 		ADBG("ipv6_add_addr: already assigned\n");
824 		err = -EEXIST;
825 		goto out;
826 	}
827 
828 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
829 
830 	if (ifa == NULL) {
831 		ADBG("ipv6_add_addr: malloc failed\n");
832 		err = -ENOBUFS;
833 		goto out;
834 	}
835 
836 	rt = addrconf_dst_alloc(idev, addr, false);
837 	if (IS_ERR(rt)) {
838 		err = PTR_ERR(rt);
839 		goto out;
840 	}
841 
842 	neigh_parms_data_state_setall(idev->nd_parms);
843 
844 	ifa->addr = *addr;
845 	if (peer_addr)
846 		ifa->peer_addr = *peer_addr;
847 
848 	spin_lock_init(&ifa->lock);
849 	spin_lock_init(&ifa->state_lock);
850 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
851 	INIT_HLIST_NODE(&ifa->addr_lst);
852 	ifa->scope = scope;
853 	ifa->prefix_len = pfxlen;
854 	ifa->flags = flags | IFA_F_TENTATIVE;
855 	ifa->valid_lft = valid_lft;
856 	ifa->prefered_lft = prefered_lft;
857 	ifa->cstamp = ifa->tstamp = jiffies;
858 	ifa->tokenized = false;
859 
860 	ifa->rt = rt;
861 
862 	ifa->idev = idev;
863 	in6_dev_hold(idev);
864 	/* For caller */
865 	in6_ifa_hold(ifa);
866 
867 	/* Add to big hash table */
868 	hash = inet6_addr_hash(addr);
869 
870 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
871 	spin_unlock(&addrconf_hash_lock);
872 
873 	write_lock(&idev->lock);
874 	/* Add to inet6_dev unicast addr list. */
875 	ipv6_link_dev_addr(idev, ifa);
876 
877 	if (ifa->flags&IFA_F_TEMPORARY) {
878 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
879 		in6_ifa_hold(ifa);
880 	}
881 
882 	in6_ifa_hold(ifa);
883 	write_unlock(&idev->lock);
884 out2:
885 	rcu_read_unlock_bh();
886 
887 	if (likely(err == 0))
888 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
889 	else {
890 		kfree(ifa);
891 		ifa = ERR_PTR(err);
892 	}
893 
894 	return ifa;
895 out:
896 	spin_unlock(&addrconf_hash_lock);
897 	goto out2;
898 }
899 
900 enum cleanup_prefix_rt_t {
901 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
902 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
903 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
904 };
905 
906 /*
907  * Check, whether the prefix for ifp would still need a prefix route
908  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
909  * constants.
910  *
911  * 1) we don't purge prefix if address was not permanent.
912  *    prefix is managed by its own lifetime.
913  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
914  * 3) if there are no addresses, delete prefix.
915  * 4) if there are still other permanent address(es),
916  *    corresponding prefix is still permanent.
917  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
918  *    don't purge the prefix, assume user space is managing it.
919  * 6) otherwise, update prefix lifetime to the
920  *    longest valid lifetime among the corresponding
921  *    addresses on the device.
922  *    Note: subsequent RA will update lifetime.
923  **/
924 static enum cleanup_prefix_rt_t
925 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
926 {
927 	struct inet6_ifaddr *ifa;
928 	struct inet6_dev *idev = ifp->idev;
929 	unsigned long lifetime;
930 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
931 
932 	*expires = jiffies;
933 
934 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
935 		if (ifa == ifp)
936 			continue;
937 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
938 				       ifp->prefix_len))
939 			continue;
940 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
941 			return CLEANUP_PREFIX_RT_NOP;
942 
943 		action = CLEANUP_PREFIX_RT_EXPIRE;
944 
945 		spin_lock(&ifa->lock);
946 
947 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
948 		/*
949 		 * Note: Because this address is
950 		 * not permanent, lifetime <
951 		 * LONG_MAX / HZ here.
952 		 */
953 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
954 			*expires = ifa->tstamp + lifetime * HZ;
955 		spin_unlock(&ifa->lock);
956 	}
957 
958 	return action;
959 }
960 
961 static void
962 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
963 {
964 	struct rt6_info *rt;
965 
966 	rt = addrconf_get_prefix_route(&ifp->addr,
967 				       ifp->prefix_len,
968 				       ifp->idev->dev,
969 				       0, RTF_GATEWAY | RTF_DEFAULT);
970 	if (rt) {
971 		if (del_rt)
972 			ip6_del_rt(rt);
973 		else {
974 			if (!(rt->rt6i_flags & RTF_EXPIRES))
975 				rt6_set_expires(rt, expires);
976 			ip6_rt_put(rt);
977 		}
978 	}
979 }
980 
981 
982 /* This function wants to get referenced ifp and releases it before return */
983 
984 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
985 {
986 	int state;
987 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
988 	unsigned long expires;
989 
990 	ASSERT_RTNL();
991 
992 	spin_lock_bh(&ifp->state_lock);
993 	state = ifp->state;
994 	ifp->state = INET6_IFADDR_STATE_DEAD;
995 	spin_unlock_bh(&ifp->state_lock);
996 
997 	if (state == INET6_IFADDR_STATE_DEAD)
998 		goto out;
999 
1000 	spin_lock_bh(&addrconf_hash_lock);
1001 	hlist_del_init_rcu(&ifp->addr_lst);
1002 	spin_unlock_bh(&addrconf_hash_lock);
1003 
1004 	write_lock_bh(&ifp->idev->lock);
1005 
1006 	if (ifp->flags&IFA_F_TEMPORARY) {
1007 		list_del(&ifp->tmp_list);
1008 		if (ifp->ifpub) {
1009 			in6_ifa_put(ifp->ifpub);
1010 			ifp->ifpub = NULL;
1011 		}
1012 		__in6_ifa_put(ifp);
1013 	}
1014 
1015 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1016 		action = check_cleanup_prefix_route(ifp, &expires);
1017 
1018 	list_del_init(&ifp->if_list);
1019 	__in6_ifa_put(ifp);
1020 
1021 	write_unlock_bh(&ifp->idev->lock);
1022 
1023 	addrconf_del_dad_work(ifp);
1024 
1025 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1026 
1027 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1028 
1029 	if (action != CLEANUP_PREFIX_RT_NOP) {
1030 		cleanup_prefix_route(ifp, expires,
1031 			action == CLEANUP_PREFIX_RT_DEL);
1032 	}
1033 
1034 	/* clean up prefsrc entries */
1035 	rt6_remove_prefsrc(ifp);
1036 out:
1037 	in6_ifa_put(ifp);
1038 }
1039 
1040 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1041 {
1042 	struct inet6_dev *idev = ifp->idev;
1043 	struct in6_addr addr, *tmpaddr;
1044 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1045 	unsigned long regen_advance;
1046 	int tmp_plen;
1047 	int ret = 0;
1048 	u32 addr_flags;
1049 	unsigned long now = jiffies;
1050 
1051 	write_lock_bh(&idev->lock);
1052 	if (ift) {
1053 		spin_lock_bh(&ift->lock);
1054 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1055 		spin_unlock_bh(&ift->lock);
1056 		tmpaddr = &addr;
1057 	} else {
1058 		tmpaddr = NULL;
1059 	}
1060 retry:
1061 	in6_dev_hold(idev);
1062 	if (idev->cnf.use_tempaddr <= 0) {
1063 		write_unlock_bh(&idev->lock);
1064 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1065 		in6_dev_put(idev);
1066 		ret = -1;
1067 		goto out;
1068 	}
1069 	spin_lock_bh(&ifp->lock);
1070 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1071 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1072 		spin_unlock_bh(&ifp->lock);
1073 		write_unlock_bh(&idev->lock);
1074 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1075 			__func__);
1076 		in6_dev_put(idev);
1077 		ret = -1;
1078 		goto out;
1079 	}
1080 	in6_ifa_hold(ifp);
1081 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1082 	__ipv6_try_regen_rndid(idev, tmpaddr);
1083 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1084 	age = (now - ifp->tstamp) / HZ;
1085 	tmp_valid_lft = min_t(__u32,
1086 			      ifp->valid_lft,
1087 			      idev->cnf.temp_valid_lft + age);
1088 	tmp_prefered_lft = min_t(__u32,
1089 				 ifp->prefered_lft,
1090 				 idev->cnf.temp_prefered_lft + age -
1091 				 idev->cnf.max_desync_factor);
1092 	tmp_plen = ifp->prefix_len;
1093 	tmp_tstamp = ifp->tstamp;
1094 	spin_unlock_bh(&ifp->lock);
1095 
1096 	regen_advance = idev->cnf.regen_max_retry *
1097 	                idev->cnf.dad_transmits *
1098 	                NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1099 	write_unlock_bh(&idev->lock);
1100 
1101 	/* A temporary address is created only if this calculated Preferred
1102 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1103 	 * an implementation must not create a temporary address with a zero
1104 	 * Preferred Lifetime.
1105 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1106 	 * temporary addresses being generated.
1107 	 */
1108 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1109 	if (tmp_prefered_lft <= regen_advance + age) {
1110 		in6_ifa_put(ifp);
1111 		in6_dev_put(idev);
1112 		ret = -1;
1113 		goto out;
1114 	}
1115 
1116 	addr_flags = IFA_F_TEMPORARY;
1117 	/* set in addrconf_prefix_rcv() */
1118 	if (ifp->flags & IFA_F_OPTIMISTIC)
1119 		addr_flags |= IFA_F_OPTIMISTIC;
1120 
1121 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1122 			    ipv6_addr_scope(&addr), addr_flags,
1123 			    tmp_valid_lft, tmp_prefered_lft);
1124 	if (IS_ERR(ift)) {
1125 		in6_ifa_put(ifp);
1126 		in6_dev_put(idev);
1127 		pr_info("%s: retry temporary address regeneration\n", __func__);
1128 		tmpaddr = &addr;
1129 		write_lock_bh(&idev->lock);
1130 		goto retry;
1131 	}
1132 
1133 	spin_lock_bh(&ift->lock);
1134 	ift->ifpub = ifp;
1135 	ift->cstamp = now;
1136 	ift->tstamp = tmp_tstamp;
1137 	spin_unlock_bh(&ift->lock);
1138 
1139 	addrconf_dad_start(ift);
1140 	in6_ifa_put(ift);
1141 	in6_dev_put(idev);
1142 out:
1143 	return ret;
1144 }
1145 
1146 /*
1147  *	Choose an appropriate source address (RFC3484)
1148  */
1149 enum {
1150 	IPV6_SADDR_RULE_INIT = 0,
1151 	IPV6_SADDR_RULE_LOCAL,
1152 	IPV6_SADDR_RULE_SCOPE,
1153 	IPV6_SADDR_RULE_PREFERRED,
1154 #ifdef CONFIG_IPV6_MIP6
1155 	IPV6_SADDR_RULE_HOA,
1156 #endif
1157 	IPV6_SADDR_RULE_OIF,
1158 	IPV6_SADDR_RULE_LABEL,
1159 	IPV6_SADDR_RULE_PRIVACY,
1160 	IPV6_SADDR_RULE_ORCHID,
1161 	IPV6_SADDR_RULE_PREFIX,
1162 	IPV6_SADDR_RULE_MAX
1163 };
1164 
1165 struct ipv6_saddr_score {
1166 	int			rule;
1167 	int			addr_type;
1168 	struct inet6_ifaddr	*ifa;
1169 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1170 	int			scopedist;
1171 	int			matchlen;
1172 };
1173 
1174 struct ipv6_saddr_dst {
1175 	const struct in6_addr *addr;
1176 	int ifindex;
1177 	int scope;
1178 	int label;
1179 	unsigned int prefs;
1180 };
1181 
1182 static inline int ipv6_saddr_preferred(int type)
1183 {
1184 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1185 		return 1;
1186 	return 0;
1187 }
1188 
1189 static int ipv6_get_saddr_eval(struct net *net,
1190 			       struct ipv6_saddr_score *score,
1191 			       struct ipv6_saddr_dst *dst,
1192 			       int i)
1193 {
1194 	int ret;
1195 
1196 	if (i <= score->rule) {
1197 		switch (i) {
1198 		case IPV6_SADDR_RULE_SCOPE:
1199 			ret = score->scopedist;
1200 			break;
1201 		case IPV6_SADDR_RULE_PREFIX:
1202 			ret = score->matchlen;
1203 			break;
1204 		default:
1205 			ret = !!test_bit(i, score->scorebits);
1206 		}
1207 		goto out;
1208 	}
1209 
1210 	switch (i) {
1211 	case IPV6_SADDR_RULE_INIT:
1212 		/* Rule 0: remember if hiscore is not ready yet */
1213 		ret = !!score->ifa;
1214 		break;
1215 	case IPV6_SADDR_RULE_LOCAL:
1216 		/* Rule 1: Prefer same address */
1217 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1218 		break;
1219 	case IPV6_SADDR_RULE_SCOPE:
1220 		/* Rule 2: Prefer appropriate scope
1221 		 *
1222 		 *      ret
1223 		 *       ^
1224 		 *    -1 |  d 15
1225 		 *    ---+--+-+---> scope
1226 		 *       |
1227 		 *       |             d is scope of the destination.
1228 		 *  B-d  |  \
1229 		 *       |   \      <- smaller scope is better if
1230 		 *  B-15 |    \        if scope is enough for destination.
1231 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1232 		 * d-C-1 | /
1233 		 *       |/         <- greater is better
1234 		 *   -C  /             if scope is not enough for destination.
1235 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1236 		 *
1237 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1238 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1239 		 * Assume B = 0 and we get C > 29.
1240 		 */
1241 		ret = __ipv6_addr_src_scope(score->addr_type);
1242 		if (ret >= dst->scope)
1243 			ret = -ret;
1244 		else
1245 			ret -= 128;	/* 30 is enough */
1246 		score->scopedist = ret;
1247 		break;
1248 	case IPV6_SADDR_RULE_PREFERRED:
1249 		/* Rule 3: Avoid deprecated and optimistic addresses */
1250 		ret = ipv6_saddr_preferred(score->addr_type) ||
1251 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1252 		break;
1253 #ifdef CONFIG_IPV6_MIP6
1254 	case IPV6_SADDR_RULE_HOA:
1255 	    {
1256 		/* Rule 4: Prefer home address */
1257 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1258 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1259 		break;
1260 	    }
1261 #endif
1262 	case IPV6_SADDR_RULE_OIF:
1263 		/* Rule 5: Prefer outgoing interface */
1264 		ret = (!dst->ifindex ||
1265 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1266 		break;
1267 	case IPV6_SADDR_RULE_LABEL:
1268 		/* Rule 6: Prefer matching label */
1269 		ret = ipv6_addr_label(net,
1270 				      &score->ifa->addr, score->addr_type,
1271 				      score->ifa->idev->dev->ifindex) == dst->label;
1272 		break;
1273 	case IPV6_SADDR_RULE_PRIVACY:
1274 	    {
1275 		/* Rule 7: Prefer public address
1276 		 * Note: prefer temporary address if use_tempaddr >= 2
1277 		 */
1278 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1279 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1280 				score->ifa->idev->cnf.use_tempaddr >= 2;
1281 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1282 		break;
1283 	    }
1284 	case IPV6_SADDR_RULE_ORCHID:
1285 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1286 		 *	    non-ORCHID vs non-ORCHID
1287 		 */
1288 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1289 			ipv6_addr_orchid(dst->addr));
1290 		break;
1291 	case IPV6_SADDR_RULE_PREFIX:
1292 		/* Rule 8: Use longest matching prefix */
1293 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1294 		if (ret > score->ifa->prefix_len)
1295 			ret = score->ifa->prefix_len;
1296 		score->matchlen = ret;
1297 		break;
1298 	default:
1299 		ret = 0;
1300 	}
1301 
1302 	if (ret)
1303 		__set_bit(i, score->scorebits);
1304 	score->rule = i;
1305 out:
1306 	return ret;
1307 }
1308 
1309 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1310 		       const struct in6_addr *daddr, unsigned int prefs,
1311 		       struct in6_addr *saddr)
1312 {
1313 	struct ipv6_saddr_score scores[2],
1314 				*score = &scores[0], *hiscore = &scores[1];
1315 	struct ipv6_saddr_dst dst;
1316 	struct net_device *dev;
1317 	int dst_type;
1318 
1319 	dst_type = __ipv6_addr_type(daddr);
1320 	dst.addr = daddr;
1321 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1322 	dst.scope = __ipv6_addr_src_scope(dst_type);
1323 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1324 	dst.prefs = prefs;
1325 
1326 	hiscore->rule = -1;
1327 	hiscore->ifa = NULL;
1328 
1329 	rcu_read_lock();
1330 
1331 	for_each_netdev_rcu(net, dev) {
1332 		struct inet6_dev *idev;
1333 
1334 		/* Candidate Source Address (section 4)
1335 		 *  - multicast and link-local destination address,
1336 		 *    the set of candidate source address MUST only
1337 		 *    include addresses assigned to interfaces
1338 		 *    belonging to the same link as the outgoing
1339 		 *    interface.
1340 		 * (- For site-local destination addresses, the
1341 		 *    set of candidate source addresses MUST only
1342 		 *    include addresses assigned to interfaces
1343 		 *    belonging to the same site as the outgoing
1344 		 *    interface.)
1345 		 */
1346 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1347 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1348 		    dst.ifindex && dev->ifindex != dst.ifindex)
1349 			continue;
1350 
1351 		idev = __in6_dev_get(dev);
1352 		if (!idev)
1353 			continue;
1354 
1355 		read_lock_bh(&idev->lock);
1356 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1357 			int i;
1358 
1359 			/*
1360 			 * - Tentative Address (RFC2462 section 5.4)
1361 			 *  - A tentative address is not considered
1362 			 *    "assigned to an interface" in the traditional
1363 			 *    sense, unless it is also flagged as optimistic.
1364 			 * - Candidate Source Address (section 4)
1365 			 *  - In any case, anycast addresses, multicast
1366 			 *    addresses, and the unspecified address MUST
1367 			 *    NOT be included in a candidate set.
1368 			 */
1369 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1370 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1371 				continue;
1372 
1373 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1374 
1375 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1376 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1377 				LIMIT_NETDEBUG(KERN_DEBUG
1378 					       "ADDRCONF: unspecified / multicast address "
1379 					       "assigned as unicast address on %s",
1380 					       dev->name);
1381 				continue;
1382 			}
1383 
1384 			score->rule = -1;
1385 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1386 
1387 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1388 				int minihiscore, miniscore;
1389 
1390 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1391 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1392 
1393 				if (minihiscore > miniscore) {
1394 					if (i == IPV6_SADDR_RULE_SCOPE &&
1395 					    score->scopedist > 0) {
1396 						/*
1397 						 * special case:
1398 						 * each remaining entry
1399 						 * has too small (not enough)
1400 						 * scope, because ifa entries
1401 						 * are sorted by their scope
1402 						 * values.
1403 						 */
1404 						goto try_nextdev;
1405 					}
1406 					break;
1407 				} else if (minihiscore < miniscore) {
1408 					if (hiscore->ifa)
1409 						in6_ifa_put(hiscore->ifa);
1410 
1411 					in6_ifa_hold(score->ifa);
1412 
1413 					swap(hiscore, score);
1414 
1415 					/* restore our iterator */
1416 					score->ifa = hiscore->ifa;
1417 
1418 					break;
1419 				}
1420 			}
1421 		}
1422 try_nextdev:
1423 		read_unlock_bh(&idev->lock);
1424 	}
1425 	rcu_read_unlock();
1426 
1427 	if (!hiscore->ifa)
1428 		return -EADDRNOTAVAIL;
1429 
1430 	*saddr = hiscore->ifa->addr;
1431 	in6_ifa_put(hiscore->ifa);
1432 	return 0;
1433 }
1434 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1435 
1436 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1437 		      u32 banned_flags)
1438 {
1439 	struct inet6_ifaddr *ifp;
1440 	int err = -EADDRNOTAVAIL;
1441 
1442 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1443 		if (ifp->scope > IFA_LINK)
1444 			break;
1445 		if (ifp->scope == IFA_LINK &&
1446 		    !(ifp->flags & banned_flags)) {
1447 			*addr = ifp->addr;
1448 			err = 0;
1449 			break;
1450 		}
1451 	}
1452 	return err;
1453 }
1454 
1455 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1456 		    u32 banned_flags)
1457 {
1458 	struct inet6_dev *idev;
1459 	int err = -EADDRNOTAVAIL;
1460 
1461 	rcu_read_lock();
1462 	idev = __in6_dev_get(dev);
1463 	if (idev) {
1464 		read_lock_bh(&idev->lock);
1465 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1466 		read_unlock_bh(&idev->lock);
1467 	}
1468 	rcu_read_unlock();
1469 	return err;
1470 }
1471 
1472 static int ipv6_count_addresses(struct inet6_dev *idev)
1473 {
1474 	int cnt = 0;
1475 	struct inet6_ifaddr *ifp;
1476 
1477 	read_lock_bh(&idev->lock);
1478 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1479 		cnt++;
1480 	read_unlock_bh(&idev->lock);
1481 	return cnt;
1482 }
1483 
1484 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1485 		  const struct net_device *dev, int strict)
1486 {
1487 	struct inet6_ifaddr *ifp;
1488 	unsigned int hash = inet6_addr_hash(addr);
1489 
1490 	rcu_read_lock_bh();
1491 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1492 		if (!net_eq(dev_net(ifp->idev->dev), net))
1493 			continue;
1494 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1495 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1496 		    (dev == NULL || ifp->idev->dev == dev ||
1497 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1498 			rcu_read_unlock_bh();
1499 			return 1;
1500 		}
1501 	}
1502 
1503 	rcu_read_unlock_bh();
1504 	return 0;
1505 }
1506 EXPORT_SYMBOL(ipv6_chk_addr);
1507 
1508 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1509 			       struct net_device *dev)
1510 {
1511 	unsigned int hash = inet6_addr_hash(addr);
1512 	struct inet6_ifaddr *ifp;
1513 
1514 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1515 		if (!net_eq(dev_net(ifp->idev->dev), net))
1516 			continue;
1517 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1518 			if (dev == NULL || ifp->idev->dev == dev)
1519 				return true;
1520 		}
1521 	}
1522 	return false;
1523 }
1524 
1525 /* Compares an address/prefix_len with addresses on device @dev.
1526  * If one is found it returns true.
1527  */
1528 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1529 	const unsigned int prefix_len, struct net_device *dev)
1530 {
1531 	struct inet6_dev *idev;
1532 	struct inet6_ifaddr *ifa;
1533 	bool ret = false;
1534 
1535 	rcu_read_lock();
1536 	idev = __in6_dev_get(dev);
1537 	if (idev) {
1538 		read_lock_bh(&idev->lock);
1539 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1540 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1541 			if (ret)
1542 				break;
1543 		}
1544 		read_unlock_bh(&idev->lock);
1545 	}
1546 	rcu_read_unlock();
1547 
1548 	return ret;
1549 }
1550 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1551 
1552 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1553 {
1554 	struct inet6_dev *idev;
1555 	struct inet6_ifaddr *ifa;
1556 	int	onlink;
1557 
1558 	onlink = 0;
1559 	rcu_read_lock();
1560 	idev = __in6_dev_get(dev);
1561 	if (idev) {
1562 		read_lock_bh(&idev->lock);
1563 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1564 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1565 						   ifa->prefix_len);
1566 			if (onlink)
1567 				break;
1568 		}
1569 		read_unlock_bh(&idev->lock);
1570 	}
1571 	rcu_read_unlock();
1572 	return onlink;
1573 }
1574 EXPORT_SYMBOL(ipv6_chk_prefix);
1575 
1576 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1577 				     struct net_device *dev, int strict)
1578 {
1579 	struct inet6_ifaddr *ifp, *result = NULL;
1580 	unsigned int hash = inet6_addr_hash(addr);
1581 
1582 	rcu_read_lock_bh();
1583 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1584 		if (!net_eq(dev_net(ifp->idev->dev), net))
1585 			continue;
1586 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1587 			if (dev == NULL || ifp->idev->dev == dev ||
1588 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1589 				result = ifp;
1590 				in6_ifa_hold(ifp);
1591 				break;
1592 			}
1593 		}
1594 	}
1595 	rcu_read_unlock_bh();
1596 
1597 	return result;
1598 }
1599 
1600 /* Gets referenced address, destroys ifaddr */
1601 
1602 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1603 {
1604 	if (ifp->flags&IFA_F_PERMANENT) {
1605 		spin_lock_bh(&ifp->lock);
1606 		addrconf_del_dad_work(ifp);
1607 		ifp->flags |= IFA_F_TENTATIVE;
1608 		if (dad_failed)
1609 			ifp->flags |= IFA_F_DADFAILED;
1610 		spin_unlock_bh(&ifp->lock);
1611 		if (dad_failed)
1612 			ipv6_ifa_notify(0, ifp);
1613 		in6_ifa_put(ifp);
1614 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1615 		struct inet6_ifaddr *ifpub;
1616 		spin_lock_bh(&ifp->lock);
1617 		ifpub = ifp->ifpub;
1618 		if (ifpub) {
1619 			in6_ifa_hold(ifpub);
1620 			spin_unlock_bh(&ifp->lock);
1621 			ipv6_create_tempaddr(ifpub, ifp);
1622 			in6_ifa_put(ifpub);
1623 		} else {
1624 			spin_unlock_bh(&ifp->lock);
1625 		}
1626 		ipv6_del_addr(ifp);
1627 	} else {
1628 		ipv6_del_addr(ifp);
1629 	}
1630 }
1631 
1632 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1633 {
1634 	int err = -ENOENT;
1635 
1636 	spin_lock_bh(&ifp->state_lock);
1637 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1638 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1639 		err = 0;
1640 	}
1641 	spin_unlock_bh(&ifp->state_lock);
1642 
1643 	return err;
1644 }
1645 
1646 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1647 {
1648 	struct inet6_dev *idev = ifp->idev;
1649 
1650 	if (addrconf_dad_end(ifp)) {
1651 		in6_ifa_put(ifp);
1652 		return;
1653 	}
1654 
1655 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1656 			     ifp->idev->dev->name, &ifp->addr);
1657 
1658 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1659 		struct in6_addr addr;
1660 
1661 		addr.s6_addr32[0] = htonl(0xfe800000);
1662 		addr.s6_addr32[1] = 0;
1663 
1664 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1665 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1666 			/* DAD failed for link-local based on MAC address */
1667 			idev->cnf.disable_ipv6 = 1;
1668 
1669 			pr_info("%s: IPv6 being disabled!\n",
1670 				ifp->idev->dev->name);
1671 		}
1672 	}
1673 
1674 	spin_lock_bh(&ifp->state_lock);
1675 	/* transition from _POSTDAD to _ERRDAD */
1676 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
1677 	spin_unlock_bh(&ifp->state_lock);
1678 
1679 	addrconf_mod_dad_work(ifp, 0);
1680 }
1681 
1682 /* Join to solicited addr multicast group. */
1683 
1684 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1685 {
1686 	struct in6_addr maddr;
1687 
1688 	ASSERT_RTNL();
1689 
1690 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1691 		return;
1692 
1693 	addrconf_addr_solict_mult(addr, &maddr);
1694 	ipv6_dev_mc_inc(dev, &maddr);
1695 }
1696 
1697 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1698 {
1699 	struct in6_addr maddr;
1700 
1701 	ASSERT_RTNL();
1702 
1703 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1704 		return;
1705 
1706 	addrconf_addr_solict_mult(addr, &maddr);
1707 	__ipv6_dev_mc_dec(idev, &maddr);
1708 }
1709 
1710 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1711 {
1712 	struct in6_addr addr;
1713 
1714 	ASSERT_RTNL();
1715 
1716 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1717 		return;
1718 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1719 	if (ipv6_addr_any(&addr))
1720 		return;
1721 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1722 }
1723 
1724 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1725 {
1726 	struct in6_addr addr;
1727 
1728 	ASSERT_RTNL();
1729 
1730 	if (ifp->prefix_len >= 127) /* RFC 6164 */
1731 		return;
1732 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1733 	if (ipv6_addr_any(&addr))
1734 		return;
1735 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1736 }
1737 
1738 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1739 {
1740 	if (dev->addr_len != ETH_ALEN)
1741 		return -1;
1742 	memcpy(eui, dev->dev_addr, 3);
1743 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1744 
1745 	/*
1746 	 * The zSeries OSA network cards can be shared among various
1747 	 * OS instances, but the OSA cards have only one MAC address.
1748 	 * This leads to duplicate address conflicts in conjunction
1749 	 * with IPv6 if more than one instance uses the same card.
1750 	 *
1751 	 * The driver for these cards can deliver a unique 16-bit
1752 	 * identifier for each instance sharing the same card.  It is
1753 	 * placed instead of 0xFFFE in the interface identifier.  The
1754 	 * "u" bit of the interface identifier is not inverted in this
1755 	 * case.  Hence the resulting interface identifier has local
1756 	 * scope according to RFC2373.
1757 	 */
1758 	if (dev->dev_id) {
1759 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1760 		eui[4] = dev->dev_id & 0xFF;
1761 	} else {
1762 		eui[3] = 0xFF;
1763 		eui[4] = 0xFE;
1764 		eui[0] ^= 2;
1765 	}
1766 	return 0;
1767 }
1768 
1769 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1770 {
1771 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1772 		return -1;
1773 	memcpy(eui, dev->dev_addr, 8);
1774 	eui[0] ^= 2;
1775 	return 0;
1776 }
1777 
1778 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
1779 {
1780 	union fwnet_hwaddr *ha;
1781 
1782 	if (dev->addr_len != FWNET_ALEN)
1783 		return -1;
1784 
1785 	ha = (union fwnet_hwaddr *)dev->dev_addr;
1786 
1787 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
1788 	eui[0] ^= 2;
1789 	return 0;
1790 }
1791 
1792 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1793 {
1794 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1795 	if (dev->addr_len != ARCNET_ALEN)
1796 		return -1;
1797 	memset(eui, 0, 7);
1798 	eui[7] = *(u8 *)dev->dev_addr;
1799 	return 0;
1800 }
1801 
1802 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1803 {
1804 	if (dev->addr_len != INFINIBAND_ALEN)
1805 		return -1;
1806 	memcpy(eui, dev->dev_addr + 12, 8);
1807 	eui[0] |= 2;
1808 	return 0;
1809 }
1810 
1811 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1812 {
1813 	if (addr == 0)
1814 		return -1;
1815 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1816 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1817 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1818 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1819 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1820 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1821 	eui[1] = 0;
1822 	eui[2] = 0x5E;
1823 	eui[3] = 0xFE;
1824 	memcpy(eui + 4, &addr, 4);
1825 	return 0;
1826 }
1827 
1828 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1829 {
1830 	if (dev->priv_flags & IFF_ISATAP)
1831 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1832 	return -1;
1833 }
1834 
1835 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1836 {
1837 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1838 }
1839 
1840 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
1841 {
1842 	memcpy(eui, dev->perm_addr, 3);
1843 	memcpy(eui + 5, dev->perm_addr + 3, 3);
1844 	eui[3] = 0xFF;
1845 	eui[4] = 0xFE;
1846 	eui[0] ^= 2;
1847 	return 0;
1848 }
1849 
1850 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1851 {
1852 	switch (dev->type) {
1853 	case ARPHRD_ETHER:
1854 	case ARPHRD_FDDI:
1855 		return addrconf_ifid_eui48(eui, dev);
1856 	case ARPHRD_ARCNET:
1857 		return addrconf_ifid_arcnet(eui, dev);
1858 	case ARPHRD_INFINIBAND:
1859 		return addrconf_ifid_infiniband(eui, dev);
1860 	case ARPHRD_SIT:
1861 		return addrconf_ifid_sit(eui, dev);
1862 	case ARPHRD_IPGRE:
1863 		return addrconf_ifid_gre(eui, dev);
1864 	case ARPHRD_6LOWPAN:
1865 	case ARPHRD_IEEE802154:
1866 		return addrconf_ifid_eui64(eui, dev);
1867 	case ARPHRD_IEEE1394:
1868 		return addrconf_ifid_ieee1394(eui, dev);
1869 	case ARPHRD_TUNNEL6:
1870 		return addrconf_ifid_ip6tnl(eui, dev);
1871 	}
1872 	return -1;
1873 }
1874 
1875 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1876 {
1877 	int err = -1;
1878 	struct inet6_ifaddr *ifp;
1879 
1880 	read_lock_bh(&idev->lock);
1881 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1882 		if (ifp->scope > IFA_LINK)
1883 			break;
1884 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1885 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1886 			err = 0;
1887 			break;
1888 		}
1889 	}
1890 	read_unlock_bh(&idev->lock);
1891 	return err;
1892 }
1893 
1894 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1895 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1896 {
1897 regen:
1898 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1899 	idev->rndid[0] &= ~0x02;
1900 
1901 	/*
1902 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1903 	 * check if generated address is not inappropriate
1904 	 *
1905 	 *  - Reserved subnet anycast (RFC 2526)
1906 	 *	11111101 11....11 1xxxxxxx
1907 	 *  - ISATAP (RFC4214) 6.1
1908 	 *	00-00-5E-FE-xx-xx-xx-xx
1909 	 *  - value 0
1910 	 *  - XXX: already assigned to an address on the device
1911 	 */
1912 	if (idev->rndid[0] == 0xfd &&
1913 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1914 	    (idev->rndid[7]&0x80))
1915 		goto regen;
1916 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1917 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1918 			goto regen;
1919 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1920 			goto regen;
1921 	}
1922 }
1923 
1924 static void ipv6_regen_rndid(unsigned long data)
1925 {
1926 	struct inet6_dev *idev = (struct inet6_dev *) data;
1927 	unsigned long expires;
1928 
1929 	rcu_read_lock_bh();
1930 	write_lock_bh(&idev->lock);
1931 
1932 	if (idev->dead)
1933 		goto out;
1934 
1935 	__ipv6_regen_rndid(idev);
1936 
1937 	expires = jiffies +
1938 		idev->cnf.temp_prefered_lft * HZ -
1939 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits *
1940 		NEIGH_VAR(idev->nd_parms, RETRANS_TIME) -
1941 		idev->cnf.max_desync_factor * HZ;
1942 	if (time_before(expires, jiffies)) {
1943 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1944 			__func__, idev->dev->name);
1945 		goto out;
1946 	}
1947 
1948 	if (!mod_timer(&idev->regen_timer, expires))
1949 		in6_dev_hold(idev);
1950 
1951 out:
1952 	write_unlock_bh(&idev->lock);
1953 	rcu_read_unlock_bh();
1954 	in6_dev_put(idev);
1955 }
1956 
1957 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1958 {
1959 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1960 		__ipv6_regen_rndid(idev);
1961 }
1962 
1963 /*
1964  *	Add prefix route.
1965  */
1966 
1967 static void
1968 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1969 		      unsigned long expires, u32 flags)
1970 {
1971 	struct fib6_config cfg = {
1972 		.fc_table = RT6_TABLE_PREFIX,
1973 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1974 		.fc_ifindex = dev->ifindex,
1975 		.fc_expires = expires,
1976 		.fc_dst_len = plen,
1977 		.fc_flags = RTF_UP | flags,
1978 		.fc_nlinfo.nl_net = dev_net(dev),
1979 		.fc_protocol = RTPROT_KERNEL,
1980 	};
1981 
1982 	cfg.fc_dst = *pfx;
1983 
1984 	/* Prevent useless cloning on PtP SIT.
1985 	   This thing is done here expecting that the whole
1986 	   class of non-broadcast devices need not cloning.
1987 	 */
1988 #if IS_ENABLED(CONFIG_IPV6_SIT)
1989 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1990 		cfg.fc_flags |= RTF_NONEXTHOP;
1991 #endif
1992 
1993 	ip6_route_add(&cfg);
1994 }
1995 
1996 
1997 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1998 						  int plen,
1999 						  const struct net_device *dev,
2000 						  u32 flags, u32 noflags)
2001 {
2002 	struct fib6_node *fn;
2003 	struct rt6_info *rt = NULL;
2004 	struct fib6_table *table;
2005 
2006 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
2007 	if (table == NULL)
2008 		return NULL;
2009 
2010 	read_lock_bh(&table->tb6_lock);
2011 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2012 	if (!fn)
2013 		goto out;
2014 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2015 		if (rt->dst.dev->ifindex != dev->ifindex)
2016 			continue;
2017 		if ((rt->rt6i_flags & flags) != flags)
2018 			continue;
2019 		if ((rt->rt6i_flags & noflags) != 0)
2020 			continue;
2021 		dst_hold(&rt->dst);
2022 		break;
2023 	}
2024 out:
2025 	read_unlock_bh(&table->tb6_lock);
2026 	return rt;
2027 }
2028 
2029 
2030 /* Create "default" multicast route to the interface */
2031 
2032 static void addrconf_add_mroute(struct net_device *dev)
2033 {
2034 	struct fib6_config cfg = {
2035 		.fc_table = RT6_TABLE_LOCAL,
2036 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2037 		.fc_ifindex = dev->ifindex,
2038 		.fc_dst_len = 8,
2039 		.fc_flags = RTF_UP,
2040 		.fc_nlinfo.nl_net = dev_net(dev),
2041 	};
2042 
2043 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2044 
2045 	ip6_route_add(&cfg);
2046 }
2047 
2048 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2049 {
2050 	struct inet6_dev *idev;
2051 
2052 	ASSERT_RTNL();
2053 
2054 	idev = ipv6_find_idev(dev);
2055 	if (!idev)
2056 		return ERR_PTR(-ENOBUFS);
2057 
2058 	if (idev->cnf.disable_ipv6)
2059 		return ERR_PTR(-EACCES);
2060 
2061 	/* Add default multicast route */
2062 	if (!(dev->flags & IFF_LOOPBACK))
2063 		addrconf_add_mroute(dev);
2064 
2065 	return idev;
2066 }
2067 
2068 static void manage_tempaddrs(struct inet6_dev *idev,
2069 			     struct inet6_ifaddr *ifp,
2070 			     __u32 valid_lft, __u32 prefered_lft,
2071 			     bool create, unsigned long now)
2072 {
2073 	u32 flags;
2074 	struct inet6_ifaddr *ift;
2075 
2076 	read_lock_bh(&idev->lock);
2077 	/* update all temporary addresses in the list */
2078 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2079 		int age, max_valid, max_prefered;
2080 
2081 		if (ifp != ift->ifpub)
2082 			continue;
2083 
2084 		/* RFC 4941 section 3.3:
2085 		 * If a received option will extend the lifetime of a public
2086 		 * address, the lifetimes of temporary addresses should
2087 		 * be extended, subject to the overall constraint that no
2088 		 * temporary addresses should ever remain "valid" or "preferred"
2089 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2090 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2091 		 */
2092 		age = (now - ift->cstamp) / HZ;
2093 		max_valid = idev->cnf.temp_valid_lft - age;
2094 		if (max_valid < 0)
2095 			max_valid = 0;
2096 
2097 		max_prefered = idev->cnf.temp_prefered_lft -
2098 			       idev->cnf.max_desync_factor - age;
2099 		if (max_prefered < 0)
2100 			max_prefered = 0;
2101 
2102 		if (valid_lft > max_valid)
2103 			valid_lft = max_valid;
2104 
2105 		if (prefered_lft > max_prefered)
2106 			prefered_lft = max_prefered;
2107 
2108 		spin_lock(&ift->lock);
2109 		flags = ift->flags;
2110 		ift->valid_lft = valid_lft;
2111 		ift->prefered_lft = prefered_lft;
2112 		ift->tstamp = now;
2113 		if (prefered_lft > 0)
2114 			ift->flags &= ~IFA_F_DEPRECATED;
2115 
2116 		spin_unlock(&ift->lock);
2117 		if (!(flags&IFA_F_TENTATIVE))
2118 			ipv6_ifa_notify(0, ift);
2119 	}
2120 
2121 	if ((create || list_empty(&idev->tempaddr_list)) &&
2122 	    idev->cnf.use_tempaddr > 0) {
2123 		/* When a new public address is created as described
2124 		 * in [ADDRCONF], also create a new temporary address.
2125 		 * Also create a temporary address if it's enabled but
2126 		 * no temporary address currently exists.
2127 		 */
2128 		read_unlock_bh(&idev->lock);
2129 		ipv6_create_tempaddr(ifp, NULL);
2130 	} else {
2131 		read_unlock_bh(&idev->lock);
2132 	}
2133 }
2134 
2135 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2136 {
2137 	struct prefix_info *pinfo;
2138 	__u32 valid_lft;
2139 	__u32 prefered_lft;
2140 	int addr_type;
2141 	struct inet6_dev *in6_dev;
2142 	struct net *net = dev_net(dev);
2143 
2144 	pinfo = (struct prefix_info *) opt;
2145 
2146 	if (len < sizeof(struct prefix_info)) {
2147 		ADBG("addrconf: prefix option too short\n");
2148 		return;
2149 	}
2150 
2151 	/*
2152 	 *	Validation checks ([ADDRCONF], page 19)
2153 	 */
2154 
2155 	addr_type = ipv6_addr_type(&pinfo->prefix);
2156 
2157 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2158 		return;
2159 
2160 	valid_lft = ntohl(pinfo->valid);
2161 	prefered_lft = ntohl(pinfo->prefered);
2162 
2163 	if (prefered_lft > valid_lft) {
2164 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2165 		return;
2166 	}
2167 
2168 	in6_dev = in6_dev_get(dev);
2169 
2170 	if (in6_dev == NULL) {
2171 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2172 				    dev->name);
2173 		return;
2174 	}
2175 
2176 	/*
2177 	 *	Two things going on here:
2178 	 *	1) Add routes for on-link prefixes
2179 	 *	2) Configure prefixes with the auto flag set
2180 	 */
2181 
2182 	if (pinfo->onlink) {
2183 		struct rt6_info *rt;
2184 		unsigned long rt_expires;
2185 
2186 		/* Avoid arithmetic overflow. Really, we could
2187 		 * save rt_expires in seconds, likely valid_lft,
2188 		 * but it would require division in fib gc, that it
2189 		 * not good.
2190 		 */
2191 		if (HZ > USER_HZ)
2192 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2193 		else
2194 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2195 
2196 		if (addrconf_finite_timeout(rt_expires))
2197 			rt_expires *= HZ;
2198 
2199 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2200 					       pinfo->prefix_len,
2201 					       dev,
2202 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2203 					       RTF_GATEWAY | RTF_DEFAULT);
2204 
2205 		if (rt) {
2206 			/* Autoconf prefix route */
2207 			if (valid_lft == 0) {
2208 				ip6_del_rt(rt);
2209 				rt = NULL;
2210 			} else if (addrconf_finite_timeout(rt_expires)) {
2211 				/* not infinity */
2212 				rt6_set_expires(rt, jiffies + rt_expires);
2213 			} else {
2214 				rt6_clean_expires(rt);
2215 			}
2216 		} else if (valid_lft) {
2217 			clock_t expires = 0;
2218 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2219 			if (addrconf_finite_timeout(rt_expires)) {
2220 				/* not infinity */
2221 				flags |= RTF_EXPIRES;
2222 				expires = jiffies_to_clock_t(rt_expires);
2223 			}
2224 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2225 					      dev, expires, flags);
2226 		}
2227 		ip6_rt_put(rt);
2228 	}
2229 
2230 	/* Try to figure out our local address for this prefix */
2231 
2232 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2233 		struct inet6_ifaddr *ifp;
2234 		struct in6_addr addr;
2235 		int create = 0, update_lft = 0;
2236 		bool tokenized = false;
2237 
2238 		if (pinfo->prefix_len == 64) {
2239 			memcpy(&addr, &pinfo->prefix, 8);
2240 
2241 			if (!ipv6_addr_any(&in6_dev->token)) {
2242 				read_lock_bh(&in6_dev->lock);
2243 				memcpy(addr.s6_addr + 8,
2244 				       in6_dev->token.s6_addr + 8, 8);
2245 				read_unlock_bh(&in6_dev->lock);
2246 				tokenized = true;
2247 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2248 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2249 				in6_dev_put(in6_dev);
2250 				return;
2251 			}
2252 			goto ok;
2253 		}
2254 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2255 				    pinfo->prefix_len);
2256 		in6_dev_put(in6_dev);
2257 		return;
2258 
2259 ok:
2260 
2261 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2262 
2263 		if (ifp == NULL && valid_lft) {
2264 			int max_addresses = in6_dev->cnf.max_addresses;
2265 			u32 addr_flags = 0;
2266 
2267 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2268 			if (in6_dev->cnf.optimistic_dad &&
2269 			    !net->ipv6.devconf_all->forwarding && sllao)
2270 				addr_flags = IFA_F_OPTIMISTIC;
2271 #endif
2272 
2273 			/* Do not allow to create too much of autoconfigured
2274 			 * addresses; this would be too easy way to crash kernel.
2275 			 */
2276 			if (!max_addresses ||
2277 			    ipv6_count_addresses(in6_dev) < max_addresses)
2278 				ifp = ipv6_add_addr(in6_dev, &addr, NULL,
2279 						    pinfo->prefix_len,
2280 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2281 						    addr_flags, valid_lft,
2282 						    prefered_lft);
2283 
2284 			if (IS_ERR_OR_NULL(ifp)) {
2285 				in6_dev_put(in6_dev);
2286 				return;
2287 			}
2288 
2289 			update_lft = 0;
2290 			create = 1;
2291 			spin_lock_bh(&ifp->lock);
2292 			ifp->flags |= IFA_F_MANAGETEMPADDR;
2293 			ifp->cstamp = jiffies;
2294 			ifp->tokenized = tokenized;
2295 			spin_unlock_bh(&ifp->lock);
2296 			addrconf_dad_start(ifp);
2297 		}
2298 
2299 		if (ifp) {
2300 			u32 flags;
2301 			unsigned long now;
2302 			u32 stored_lft;
2303 
2304 			/* update lifetime (RFC2462 5.5.3 e) */
2305 			spin_lock(&ifp->lock);
2306 			now = jiffies;
2307 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2308 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2309 			else
2310 				stored_lft = 0;
2311 			if (!update_lft && !create && stored_lft) {
2312 				const u32 minimum_lft = min(
2313 					stored_lft, (u32)MIN_VALID_LIFETIME);
2314 				valid_lft = max(valid_lft, minimum_lft);
2315 
2316 				/* RFC4862 Section 5.5.3e:
2317 				 * "Note that the preferred lifetime of the
2318 				 *  corresponding address is always reset to
2319 				 *  the Preferred Lifetime in the received
2320 				 *  Prefix Information option, regardless of
2321 				 *  whether the valid lifetime is also reset or
2322 				 *  ignored."
2323 				 *
2324 				 * So we should always update prefered_lft here.
2325 				 */
2326 				update_lft = 1;
2327 			}
2328 
2329 			if (update_lft) {
2330 				ifp->valid_lft = valid_lft;
2331 				ifp->prefered_lft = prefered_lft;
2332 				ifp->tstamp = now;
2333 				flags = ifp->flags;
2334 				ifp->flags &= ~IFA_F_DEPRECATED;
2335 				spin_unlock(&ifp->lock);
2336 
2337 				if (!(flags&IFA_F_TENTATIVE))
2338 					ipv6_ifa_notify(0, ifp);
2339 			} else
2340 				spin_unlock(&ifp->lock);
2341 
2342 			manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2343 					 create, now);
2344 
2345 			in6_ifa_put(ifp);
2346 			addrconf_verify();
2347 		}
2348 	}
2349 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2350 	in6_dev_put(in6_dev);
2351 }
2352 
2353 /*
2354  *	Set destination address.
2355  *	Special case for SIT interfaces where we create a new "virtual"
2356  *	device.
2357  */
2358 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2359 {
2360 	struct in6_ifreq ireq;
2361 	struct net_device *dev;
2362 	int err = -EINVAL;
2363 
2364 	rtnl_lock();
2365 
2366 	err = -EFAULT;
2367 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2368 		goto err_exit;
2369 
2370 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2371 
2372 	err = -ENODEV;
2373 	if (dev == NULL)
2374 		goto err_exit;
2375 
2376 #if IS_ENABLED(CONFIG_IPV6_SIT)
2377 	if (dev->type == ARPHRD_SIT) {
2378 		const struct net_device_ops *ops = dev->netdev_ops;
2379 		struct ifreq ifr;
2380 		struct ip_tunnel_parm p;
2381 
2382 		err = -EADDRNOTAVAIL;
2383 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2384 			goto err_exit;
2385 
2386 		memset(&p, 0, sizeof(p));
2387 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2388 		p.iph.saddr = 0;
2389 		p.iph.version = 4;
2390 		p.iph.ihl = 5;
2391 		p.iph.protocol = IPPROTO_IPV6;
2392 		p.iph.ttl = 64;
2393 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2394 
2395 		if (ops->ndo_do_ioctl) {
2396 			mm_segment_t oldfs = get_fs();
2397 
2398 			set_fs(KERNEL_DS);
2399 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2400 			set_fs(oldfs);
2401 		} else
2402 			err = -EOPNOTSUPP;
2403 
2404 		if (err == 0) {
2405 			err = -ENOBUFS;
2406 			dev = __dev_get_by_name(net, p.name);
2407 			if (!dev)
2408 				goto err_exit;
2409 			err = dev_open(dev);
2410 		}
2411 	}
2412 #endif
2413 
2414 err_exit:
2415 	rtnl_unlock();
2416 	return err;
2417 }
2418 
2419 /*
2420  *	Manual configuration of address on an interface
2421  */
2422 static int inet6_addr_add(struct net *net, int ifindex,
2423 			  const struct in6_addr *pfx,
2424 			  const struct in6_addr *peer_pfx,
2425 			  unsigned int plen, __u32 ifa_flags,
2426 			  __u32 prefered_lft, __u32 valid_lft)
2427 {
2428 	struct inet6_ifaddr *ifp;
2429 	struct inet6_dev *idev;
2430 	struct net_device *dev;
2431 	int scope;
2432 	u32 flags;
2433 	clock_t expires;
2434 	unsigned long timeout;
2435 
2436 	ASSERT_RTNL();
2437 
2438 	if (plen > 128)
2439 		return -EINVAL;
2440 
2441 	/* check the lifetime */
2442 	if (!valid_lft || prefered_lft > valid_lft)
2443 		return -EINVAL;
2444 
2445 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2446 		return -EINVAL;
2447 
2448 	dev = __dev_get_by_index(net, ifindex);
2449 	if (!dev)
2450 		return -ENODEV;
2451 
2452 	idev = addrconf_add_dev(dev);
2453 	if (IS_ERR(idev))
2454 		return PTR_ERR(idev);
2455 
2456 	scope = ipv6_addr_scope(pfx);
2457 
2458 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2459 	if (addrconf_finite_timeout(timeout)) {
2460 		expires = jiffies_to_clock_t(timeout * HZ);
2461 		valid_lft = timeout;
2462 		flags = RTF_EXPIRES;
2463 	} else {
2464 		expires = 0;
2465 		flags = 0;
2466 		ifa_flags |= IFA_F_PERMANENT;
2467 	}
2468 
2469 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2470 	if (addrconf_finite_timeout(timeout)) {
2471 		if (timeout == 0)
2472 			ifa_flags |= IFA_F_DEPRECATED;
2473 		prefered_lft = timeout;
2474 	}
2475 
2476 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2477 			    valid_lft, prefered_lft);
2478 
2479 	if (!IS_ERR(ifp)) {
2480 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2481 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2482 					      expires, flags);
2483 		}
2484 
2485 		/*
2486 		 * Note that section 3.1 of RFC 4429 indicates
2487 		 * that the Optimistic flag should not be set for
2488 		 * manually configured addresses
2489 		 */
2490 		addrconf_dad_start(ifp);
2491 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2492 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2493 					 true, jiffies);
2494 		in6_ifa_put(ifp);
2495 		addrconf_verify_rtnl();
2496 		return 0;
2497 	}
2498 
2499 	return PTR_ERR(ifp);
2500 }
2501 
2502 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2503 			  const struct in6_addr *pfx, unsigned int plen)
2504 {
2505 	struct inet6_ifaddr *ifp;
2506 	struct inet6_dev *idev;
2507 	struct net_device *dev;
2508 
2509 	if (plen > 128)
2510 		return -EINVAL;
2511 
2512 	dev = __dev_get_by_index(net, ifindex);
2513 	if (!dev)
2514 		return -ENODEV;
2515 
2516 	if ((idev = __in6_dev_get(dev)) == NULL)
2517 		return -ENXIO;
2518 
2519 	read_lock_bh(&idev->lock);
2520 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2521 		if (ifp->prefix_len == plen &&
2522 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2523 			in6_ifa_hold(ifp);
2524 			read_unlock_bh(&idev->lock);
2525 
2526 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2527 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2528 				manage_tempaddrs(idev, ifp, 0, 0, false,
2529 						 jiffies);
2530 			ipv6_del_addr(ifp);
2531 			addrconf_verify_rtnl();
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, 0, &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 int addrconf_notify(struct notifier_block *this, unsigned long event,
2817 			   void *ptr)
2818 {
2819 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2820 	struct inet6_dev *idev = __in6_dev_get(dev);
2821 	int run_pending = 0;
2822 	int err;
2823 
2824 	switch (event) {
2825 	case NETDEV_REGISTER:
2826 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2827 			idev = ipv6_add_dev(dev);
2828 			if (!idev)
2829 				return notifier_from_errno(-ENOMEM);
2830 		}
2831 		break;
2832 
2833 	case NETDEV_UP:
2834 	case NETDEV_CHANGE:
2835 		if (dev->flags & IFF_SLAVE)
2836 			break;
2837 
2838 		if (event == NETDEV_UP) {
2839 			if (!addrconf_qdisc_ok(dev)) {
2840 				/* device is not ready yet. */
2841 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2842 					dev->name);
2843 				break;
2844 			}
2845 
2846 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2847 				idev = ipv6_add_dev(dev);
2848 
2849 			if (idev) {
2850 				idev->if_flags |= IF_READY;
2851 				run_pending = 1;
2852 			}
2853 		} else {
2854 			if (!addrconf_qdisc_ok(dev)) {
2855 				/* device is still not ready. */
2856 				break;
2857 			}
2858 
2859 			if (idev) {
2860 				if (idev->if_flags & IF_READY)
2861 					/* device is already configured. */
2862 					break;
2863 				idev->if_flags |= IF_READY;
2864 			}
2865 
2866 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2867 				dev->name);
2868 
2869 			run_pending = 1;
2870 		}
2871 
2872 		switch (dev->type) {
2873 #if IS_ENABLED(CONFIG_IPV6_SIT)
2874 		case ARPHRD_SIT:
2875 			addrconf_sit_config(dev);
2876 			break;
2877 #endif
2878 #if IS_ENABLED(CONFIG_NET_IPGRE)
2879 		case ARPHRD_IPGRE:
2880 			addrconf_gre_config(dev);
2881 			break;
2882 #endif
2883 		case ARPHRD_LOOPBACK:
2884 			init_loopback(dev);
2885 			break;
2886 
2887 		default:
2888 			addrconf_dev_config(dev);
2889 			break;
2890 		}
2891 
2892 		if (idev) {
2893 			if (run_pending)
2894 				addrconf_dad_run(idev);
2895 
2896 			/*
2897 			 * If the MTU changed during the interface down,
2898 			 * when the interface up, the changed MTU must be
2899 			 * reflected in the idev as well as routers.
2900 			 */
2901 			if (idev->cnf.mtu6 != dev->mtu &&
2902 			    dev->mtu >= IPV6_MIN_MTU) {
2903 				rt6_mtu_change(dev, dev->mtu);
2904 				idev->cnf.mtu6 = dev->mtu;
2905 			}
2906 			idev->tstamp = jiffies;
2907 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2908 
2909 			/*
2910 			 * If the changed mtu during down is lower than
2911 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2912 			 */
2913 			if (dev->mtu < IPV6_MIN_MTU)
2914 				addrconf_ifdown(dev, 1);
2915 		}
2916 		break;
2917 
2918 	case NETDEV_CHANGEMTU:
2919 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2920 			rt6_mtu_change(dev, dev->mtu);
2921 			idev->cnf.mtu6 = dev->mtu;
2922 			break;
2923 		}
2924 
2925 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2926 			idev = ipv6_add_dev(dev);
2927 			if (idev)
2928 				break;
2929 		}
2930 
2931 		/*
2932 		 * if MTU under IPV6_MIN_MTU.
2933 		 * Stop IPv6 on this interface.
2934 		 */
2935 
2936 	case NETDEV_DOWN:
2937 	case NETDEV_UNREGISTER:
2938 		/*
2939 		 *	Remove all addresses from this interface.
2940 		 */
2941 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2942 		break;
2943 
2944 	case NETDEV_CHANGENAME:
2945 		if (idev) {
2946 			snmp6_unregister_dev(idev);
2947 			addrconf_sysctl_unregister(idev);
2948 			addrconf_sysctl_register(idev);
2949 			err = snmp6_register_dev(idev);
2950 			if (err)
2951 				return notifier_from_errno(err);
2952 		}
2953 		break;
2954 
2955 	case NETDEV_PRE_TYPE_CHANGE:
2956 	case NETDEV_POST_TYPE_CHANGE:
2957 		addrconf_type_change(dev, event);
2958 		break;
2959 	}
2960 
2961 	return NOTIFY_OK;
2962 }
2963 
2964 /*
2965  *	addrconf module should be notified of a device going up
2966  */
2967 static struct notifier_block ipv6_dev_notf = {
2968 	.notifier_call = addrconf_notify,
2969 };
2970 
2971 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2972 {
2973 	struct inet6_dev *idev;
2974 	ASSERT_RTNL();
2975 
2976 	idev = __in6_dev_get(dev);
2977 
2978 	if (event == NETDEV_POST_TYPE_CHANGE)
2979 		ipv6_mc_remap(idev);
2980 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2981 		ipv6_mc_unmap(idev);
2982 }
2983 
2984 static int addrconf_ifdown(struct net_device *dev, int how)
2985 {
2986 	struct net *net = dev_net(dev);
2987 	struct inet6_dev *idev;
2988 	struct inet6_ifaddr *ifa;
2989 	int state, i;
2990 
2991 	ASSERT_RTNL();
2992 
2993 	rt6_ifdown(net, dev);
2994 	neigh_ifdown(&nd_tbl, dev);
2995 
2996 	idev = __in6_dev_get(dev);
2997 	if (idev == NULL)
2998 		return -ENODEV;
2999 
3000 	/*
3001 	 * Step 1: remove reference to ipv6 device from parent device.
3002 	 *	   Do not dev_put!
3003 	 */
3004 	if (how) {
3005 		idev->dead = 1;
3006 
3007 		/* protected by rtnl_lock */
3008 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3009 
3010 		/* Step 1.5: remove snmp6 entry */
3011 		snmp6_unregister_dev(idev);
3012 
3013 	}
3014 
3015 	/* Step 2: clear hash table */
3016 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3017 		struct hlist_head *h = &inet6_addr_lst[i];
3018 
3019 		spin_lock_bh(&addrconf_hash_lock);
3020 	restart:
3021 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3022 			if (ifa->idev == idev) {
3023 				hlist_del_init_rcu(&ifa->addr_lst);
3024 				addrconf_del_dad_work(ifa);
3025 				goto restart;
3026 			}
3027 		}
3028 		spin_unlock_bh(&addrconf_hash_lock);
3029 	}
3030 
3031 	write_lock_bh(&idev->lock);
3032 
3033 	addrconf_del_rs_timer(idev);
3034 
3035 	/* Step 2: clear flags for stateless addrconf */
3036 	if (!how)
3037 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3038 
3039 	if (how && del_timer(&idev->regen_timer))
3040 		in6_dev_put(idev);
3041 
3042 	/* Step 3: clear tempaddr list */
3043 	while (!list_empty(&idev->tempaddr_list)) {
3044 		ifa = list_first_entry(&idev->tempaddr_list,
3045 				       struct inet6_ifaddr, tmp_list);
3046 		list_del(&ifa->tmp_list);
3047 		write_unlock_bh(&idev->lock);
3048 		spin_lock_bh(&ifa->lock);
3049 
3050 		if (ifa->ifpub) {
3051 			in6_ifa_put(ifa->ifpub);
3052 			ifa->ifpub = NULL;
3053 		}
3054 		spin_unlock_bh(&ifa->lock);
3055 		in6_ifa_put(ifa);
3056 		write_lock_bh(&idev->lock);
3057 	}
3058 
3059 	while (!list_empty(&idev->addr_list)) {
3060 		ifa = list_first_entry(&idev->addr_list,
3061 				       struct inet6_ifaddr, if_list);
3062 		addrconf_del_dad_work(ifa);
3063 
3064 		list_del(&ifa->if_list);
3065 
3066 		write_unlock_bh(&idev->lock);
3067 
3068 		spin_lock_bh(&ifa->state_lock);
3069 		state = ifa->state;
3070 		ifa->state = INET6_IFADDR_STATE_DEAD;
3071 		spin_unlock_bh(&ifa->state_lock);
3072 
3073 		if (state != INET6_IFADDR_STATE_DEAD) {
3074 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3075 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3076 		}
3077 		in6_ifa_put(ifa);
3078 
3079 		write_lock_bh(&idev->lock);
3080 	}
3081 
3082 	write_unlock_bh(&idev->lock);
3083 
3084 	/* Step 5: Discard multicast list */
3085 	if (how)
3086 		ipv6_mc_destroy_dev(idev);
3087 	else
3088 		ipv6_mc_down(idev);
3089 
3090 	idev->tstamp = jiffies;
3091 
3092 	/* Last: Shot the device (if unregistered) */
3093 	if (how) {
3094 		addrconf_sysctl_unregister(idev);
3095 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3096 		neigh_ifdown(&nd_tbl, dev);
3097 		in6_dev_put(idev);
3098 	}
3099 	return 0;
3100 }
3101 
3102 static void addrconf_rs_timer(unsigned long data)
3103 {
3104 	struct inet6_dev *idev = (struct inet6_dev *)data;
3105 	struct net_device *dev = idev->dev;
3106 	struct in6_addr lladdr;
3107 
3108 	write_lock(&idev->lock);
3109 	if (idev->dead || !(idev->if_flags & IF_READY))
3110 		goto out;
3111 
3112 	if (!ipv6_accept_ra(idev))
3113 		goto out;
3114 
3115 	/* Announcement received after solicitation was sent */
3116 	if (idev->if_flags & IF_RA_RCVD)
3117 		goto out;
3118 
3119 	if (idev->rs_probes++ < idev->cnf.rtr_solicits) {
3120 		write_unlock(&idev->lock);
3121 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3122 			ndisc_send_rs(dev, &lladdr,
3123 				      &in6addr_linklocal_allrouters);
3124 		else
3125 			goto put;
3126 
3127 		write_lock(&idev->lock);
3128 		/* The wait after the last probe can be shorter */
3129 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3130 					     idev->cnf.rtr_solicits) ?
3131 				      idev->cnf.rtr_solicit_delay :
3132 				      idev->cnf.rtr_solicit_interval);
3133 	} else {
3134 		/*
3135 		 * Note: we do not support deprecated "all on-link"
3136 		 * assumption any longer.
3137 		 */
3138 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3139 	}
3140 
3141 out:
3142 	write_unlock(&idev->lock);
3143 put:
3144 	in6_dev_put(idev);
3145 }
3146 
3147 /*
3148  *	Duplicate Address Detection
3149  */
3150 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3151 {
3152 	unsigned long rand_num;
3153 	struct inet6_dev *idev = ifp->idev;
3154 
3155 	if (ifp->flags & IFA_F_OPTIMISTIC)
3156 		rand_num = 0;
3157 	else
3158 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3159 
3160 	ifp->dad_probes = idev->cnf.dad_transmits;
3161 	addrconf_mod_dad_work(ifp, rand_num);
3162 }
3163 
3164 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3165 {
3166 	struct inet6_dev *idev = ifp->idev;
3167 	struct net_device *dev = idev->dev;
3168 
3169 	addrconf_join_solict(dev, &ifp->addr);
3170 
3171 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3172 
3173 	read_lock_bh(&idev->lock);
3174 	spin_lock(&ifp->lock);
3175 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3176 		goto out;
3177 
3178 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3179 	    idev->cnf.accept_dad < 1 ||
3180 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3181 	    ifp->flags & IFA_F_NODAD) {
3182 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3183 		spin_unlock(&ifp->lock);
3184 		read_unlock_bh(&idev->lock);
3185 
3186 		addrconf_dad_completed(ifp);
3187 		return;
3188 	}
3189 
3190 	if (!(idev->if_flags & IF_READY)) {
3191 		spin_unlock(&ifp->lock);
3192 		read_unlock_bh(&idev->lock);
3193 		/*
3194 		 * If the device is not ready:
3195 		 * - keep it tentative if it is a permanent address.
3196 		 * - otherwise, kill it.
3197 		 */
3198 		in6_ifa_hold(ifp);
3199 		addrconf_dad_stop(ifp, 0);
3200 		return;
3201 	}
3202 
3203 	/*
3204 	 * Optimistic nodes can start receiving
3205 	 * Frames right away
3206 	 */
3207 	if (ifp->flags & IFA_F_OPTIMISTIC)
3208 		ip6_ins_rt(ifp->rt);
3209 
3210 	addrconf_dad_kick(ifp);
3211 out:
3212 	spin_unlock(&ifp->lock);
3213 	read_unlock_bh(&idev->lock);
3214 }
3215 
3216 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3217 {
3218 	bool begin_dad = false;
3219 
3220 	spin_lock_bh(&ifp->state_lock);
3221 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3222 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3223 		begin_dad = true;
3224 	}
3225 	spin_unlock_bh(&ifp->state_lock);
3226 
3227 	if (begin_dad)
3228 		addrconf_mod_dad_work(ifp, 0);
3229 }
3230 
3231 static void addrconf_dad_work(struct work_struct *w)
3232 {
3233 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3234 						struct inet6_ifaddr,
3235 						dad_work);
3236 	struct inet6_dev *idev = ifp->idev;
3237 	struct in6_addr mcaddr;
3238 
3239 	enum {
3240 		DAD_PROCESS,
3241 		DAD_BEGIN,
3242 		DAD_ABORT,
3243 	} action = DAD_PROCESS;
3244 
3245 	rtnl_lock();
3246 
3247 	spin_lock_bh(&ifp->state_lock);
3248 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3249 		action = DAD_BEGIN;
3250 		ifp->state = INET6_IFADDR_STATE_DAD;
3251 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3252 		action = DAD_ABORT;
3253 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3254 	}
3255 	spin_unlock_bh(&ifp->state_lock);
3256 
3257 	if (action == DAD_BEGIN) {
3258 		addrconf_dad_begin(ifp);
3259 		goto out;
3260 	} else if (action == DAD_ABORT) {
3261 		addrconf_dad_stop(ifp, 1);
3262 		goto out;
3263 	}
3264 
3265 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3266 		goto out;
3267 
3268 	write_lock_bh(&idev->lock);
3269 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3270 		write_unlock_bh(&idev->lock);
3271 		goto out;
3272 	}
3273 
3274 	spin_lock(&ifp->lock);
3275 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3276 		spin_unlock(&ifp->lock);
3277 		write_unlock_bh(&idev->lock);
3278 		goto out;
3279 	}
3280 
3281 	if (ifp->dad_probes == 0) {
3282 		/*
3283 		 * DAD was successful
3284 		 */
3285 
3286 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3287 		spin_unlock(&ifp->lock);
3288 		write_unlock_bh(&idev->lock);
3289 
3290 		addrconf_dad_completed(ifp);
3291 
3292 		goto out;
3293 	}
3294 
3295 	ifp->dad_probes--;
3296 	addrconf_mod_dad_work(ifp,
3297 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3298 	spin_unlock(&ifp->lock);
3299 	write_unlock_bh(&idev->lock);
3300 
3301 	/* send a neighbour solicitation for our addr */
3302 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3303 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3304 out:
3305 	in6_ifa_put(ifp);
3306 	rtnl_unlock();
3307 }
3308 
3309 /* ifp->idev must be at least read locked */
3310 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3311 {
3312 	struct inet6_ifaddr *ifpiter;
3313 	struct inet6_dev *idev = ifp->idev;
3314 
3315 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3316 		if (ifpiter->scope > IFA_LINK)
3317 			break;
3318 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3319 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3320 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3321 		    IFA_F_PERMANENT)
3322 			return false;
3323 	}
3324 	return true;
3325 }
3326 
3327 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3328 {
3329 	struct net_device *dev = ifp->idev->dev;
3330 	struct in6_addr lladdr;
3331 	bool send_rs, send_mld;
3332 
3333 	addrconf_del_dad_work(ifp);
3334 
3335 	/*
3336 	 *	Configure the address for reception. Now it is valid.
3337 	 */
3338 
3339 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3340 
3341 	/* If added prefix is link local and we are prepared to process
3342 	   router advertisements, start sending router solicitations.
3343 	 */
3344 
3345 	read_lock_bh(&ifp->idev->lock);
3346 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
3347 	send_rs = send_mld &&
3348 		  ipv6_accept_ra(ifp->idev) &&
3349 		  ifp->idev->cnf.rtr_solicits > 0 &&
3350 		  (dev->flags&IFF_LOOPBACK) == 0;
3351 	read_unlock_bh(&ifp->idev->lock);
3352 
3353 	/* While dad is in progress mld report's source address is in6_addrany.
3354 	 * Resend with proper ll now.
3355 	 */
3356 	if (send_mld)
3357 		ipv6_mc_dad_complete(ifp->idev);
3358 
3359 	if (send_rs) {
3360 		/*
3361 		 *	If a host as already performed a random delay
3362 		 *	[...] as part of DAD [...] there is no need
3363 		 *	to delay again before sending the first RS
3364 		 */
3365 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3366 			return;
3367 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
3368 
3369 		write_lock_bh(&ifp->idev->lock);
3370 		spin_lock(&ifp->lock);
3371 		ifp->idev->rs_probes = 1;
3372 		ifp->idev->if_flags |= IF_RS_SENT;
3373 		addrconf_mod_rs_timer(ifp->idev,
3374 				      ifp->idev->cnf.rtr_solicit_interval);
3375 		spin_unlock(&ifp->lock);
3376 		write_unlock_bh(&ifp->idev->lock);
3377 	}
3378 }
3379 
3380 static void addrconf_dad_run(struct inet6_dev *idev)
3381 {
3382 	struct inet6_ifaddr *ifp;
3383 
3384 	read_lock_bh(&idev->lock);
3385 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3386 		spin_lock(&ifp->lock);
3387 		if (ifp->flags & IFA_F_TENTATIVE &&
3388 		    ifp->state == INET6_IFADDR_STATE_DAD)
3389 			addrconf_dad_kick(ifp);
3390 		spin_unlock(&ifp->lock);
3391 	}
3392 	read_unlock_bh(&idev->lock);
3393 }
3394 
3395 #ifdef CONFIG_PROC_FS
3396 struct if6_iter_state {
3397 	struct seq_net_private p;
3398 	int bucket;
3399 	int offset;
3400 };
3401 
3402 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3403 {
3404 	struct inet6_ifaddr *ifa = NULL;
3405 	struct if6_iter_state *state = seq->private;
3406 	struct net *net = seq_file_net(seq);
3407 	int p = 0;
3408 
3409 	/* initial bucket if pos is 0 */
3410 	if (pos == 0) {
3411 		state->bucket = 0;
3412 		state->offset = 0;
3413 	}
3414 
3415 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3416 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
3417 					 addr_lst) {
3418 			if (!net_eq(dev_net(ifa->idev->dev), net))
3419 				continue;
3420 			/* sync with offset */
3421 			if (p < state->offset) {
3422 				p++;
3423 				continue;
3424 			}
3425 			state->offset++;
3426 			return ifa;
3427 		}
3428 
3429 		/* prepare for next bucket */
3430 		state->offset = 0;
3431 		p = 0;
3432 	}
3433 	return NULL;
3434 }
3435 
3436 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3437 					 struct inet6_ifaddr *ifa)
3438 {
3439 	struct if6_iter_state *state = seq->private;
3440 	struct net *net = seq_file_net(seq);
3441 
3442 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
3443 		if (!net_eq(dev_net(ifa->idev->dev), net))
3444 			continue;
3445 		state->offset++;
3446 		return ifa;
3447 	}
3448 
3449 	while (++state->bucket < IN6_ADDR_HSIZE) {
3450 		state->offset = 0;
3451 		hlist_for_each_entry_rcu_bh(ifa,
3452 				     &inet6_addr_lst[state->bucket], addr_lst) {
3453 			if (!net_eq(dev_net(ifa->idev->dev), net))
3454 				continue;
3455 			state->offset++;
3456 			return ifa;
3457 		}
3458 	}
3459 
3460 	return NULL;
3461 }
3462 
3463 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3464 	__acquires(rcu_bh)
3465 {
3466 	rcu_read_lock_bh();
3467 	return if6_get_first(seq, *pos);
3468 }
3469 
3470 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3471 {
3472 	struct inet6_ifaddr *ifa;
3473 
3474 	ifa = if6_get_next(seq, v);
3475 	++*pos;
3476 	return ifa;
3477 }
3478 
3479 static void if6_seq_stop(struct seq_file *seq, void *v)
3480 	__releases(rcu_bh)
3481 {
3482 	rcu_read_unlock_bh();
3483 }
3484 
3485 static int if6_seq_show(struct seq_file *seq, void *v)
3486 {
3487 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3488 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3489 		   &ifp->addr,
3490 		   ifp->idev->dev->ifindex,
3491 		   ifp->prefix_len,
3492 		   ifp->scope,
3493 		   (u8) ifp->flags,
3494 		   ifp->idev->dev->name);
3495 	return 0;
3496 }
3497 
3498 static const struct seq_operations if6_seq_ops = {
3499 	.start	= if6_seq_start,
3500 	.next	= if6_seq_next,
3501 	.show	= if6_seq_show,
3502 	.stop	= if6_seq_stop,
3503 };
3504 
3505 static int if6_seq_open(struct inode *inode, struct file *file)
3506 {
3507 	return seq_open_net(inode, file, &if6_seq_ops,
3508 			    sizeof(struct if6_iter_state));
3509 }
3510 
3511 static const struct file_operations if6_fops = {
3512 	.owner		= THIS_MODULE,
3513 	.open		= if6_seq_open,
3514 	.read		= seq_read,
3515 	.llseek		= seq_lseek,
3516 	.release	= seq_release_net,
3517 };
3518 
3519 static int __net_init if6_proc_net_init(struct net *net)
3520 {
3521 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
3522 		return -ENOMEM;
3523 	return 0;
3524 }
3525 
3526 static void __net_exit if6_proc_net_exit(struct net *net)
3527 {
3528 	remove_proc_entry("if_inet6", net->proc_net);
3529 }
3530 
3531 static struct pernet_operations if6_proc_net_ops = {
3532        .init = if6_proc_net_init,
3533        .exit = if6_proc_net_exit,
3534 };
3535 
3536 int __init if6_proc_init(void)
3537 {
3538 	return register_pernet_subsys(&if6_proc_net_ops);
3539 }
3540 
3541 void if6_proc_exit(void)
3542 {
3543 	unregister_pernet_subsys(&if6_proc_net_ops);
3544 }
3545 #endif	/* CONFIG_PROC_FS */
3546 
3547 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3548 /* Check if address is a home address configured on any interface. */
3549 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3550 {
3551 	int ret = 0;
3552 	struct inet6_ifaddr *ifp = NULL;
3553 	unsigned int hash = inet6_addr_hash(addr);
3554 
3555 	rcu_read_lock_bh();
3556 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
3557 		if (!net_eq(dev_net(ifp->idev->dev), net))
3558 			continue;
3559 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3560 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3561 			ret = 1;
3562 			break;
3563 		}
3564 	}
3565 	rcu_read_unlock_bh();
3566 	return ret;
3567 }
3568 #endif
3569 
3570 /*
3571  *	Periodic address status verification
3572  */
3573 
3574 static void addrconf_verify_rtnl(void)
3575 {
3576 	unsigned long now, next, next_sec, next_sched;
3577 	struct inet6_ifaddr *ifp;
3578 	int i;
3579 
3580 	ASSERT_RTNL();
3581 
3582 	rcu_read_lock_bh();
3583 	now = jiffies;
3584 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3585 
3586 	cancel_delayed_work(&addr_chk_work);
3587 
3588 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3589 restart:
3590 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
3591 			unsigned long age;
3592 
3593 			/* When setting preferred_lft to a value not zero or
3594 			 * infinity, while valid_lft is infinity
3595 			 * IFA_F_PERMANENT has a non-infinity life time.
3596 			 */
3597 			if ((ifp->flags & IFA_F_PERMANENT) &&
3598 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
3599 				continue;
3600 
3601 			spin_lock(&ifp->lock);
3602 			/* We try to batch several events at once. */
3603 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3604 
3605 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3606 			    age >= ifp->valid_lft) {
3607 				spin_unlock(&ifp->lock);
3608 				in6_ifa_hold(ifp);
3609 				ipv6_del_addr(ifp);
3610 				goto restart;
3611 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3612 				spin_unlock(&ifp->lock);
3613 				continue;
3614 			} else if (age >= ifp->prefered_lft) {
3615 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3616 				int deprecate = 0;
3617 
3618 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3619 					deprecate = 1;
3620 					ifp->flags |= IFA_F_DEPRECATED;
3621 				}
3622 
3623 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
3624 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
3625 					next = ifp->tstamp + ifp->valid_lft * HZ;
3626 
3627 				spin_unlock(&ifp->lock);
3628 
3629 				if (deprecate) {
3630 					in6_ifa_hold(ifp);
3631 
3632 					ipv6_ifa_notify(0, ifp);
3633 					in6_ifa_put(ifp);
3634 					goto restart;
3635 				}
3636 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3637 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3638 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3639 					ifp->idev->cnf.dad_transmits *
3640 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
3641 
3642 				if (age >= ifp->prefered_lft - regen_advance) {
3643 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3644 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3645 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3646 					if (!ifp->regen_count && ifpub) {
3647 						ifp->regen_count++;
3648 						in6_ifa_hold(ifp);
3649 						in6_ifa_hold(ifpub);
3650 						spin_unlock(&ifp->lock);
3651 
3652 						spin_lock(&ifpub->lock);
3653 						ifpub->regen_count = 0;
3654 						spin_unlock(&ifpub->lock);
3655 						ipv6_create_tempaddr(ifpub, ifp);
3656 						in6_ifa_put(ifpub);
3657 						in6_ifa_put(ifp);
3658 						goto restart;
3659 					}
3660 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3661 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3662 				spin_unlock(&ifp->lock);
3663 			} else {
3664 				/* ifp->prefered_lft <= ifp->valid_lft */
3665 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3666 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3667 				spin_unlock(&ifp->lock);
3668 			}
3669 		}
3670 	}
3671 
3672 	next_sec = round_jiffies_up(next);
3673 	next_sched = next;
3674 
3675 	/* If rounded timeout is accurate enough, accept it. */
3676 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3677 		next_sched = next_sec;
3678 
3679 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3680 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3681 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3682 
3683 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3684 	      now, next, next_sec, next_sched);
3685 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
3686 	rcu_read_unlock_bh();
3687 }
3688 
3689 static void addrconf_verify_work(struct work_struct *w)
3690 {
3691 	rtnl_lock();
3692 	addrconf_verify_rtnl();
3693 	rtnl_unlock();
3694 }
3695 
3696 static void addrconf_verify(void)
3697 {
3698 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
3699 }
3700 
3701 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
3702 				     struct in6_addr **peer_pfx)
3703 {
3704 	struct in6_addr *pfx = NULL;
3705 
3706 	*peer_pfx = NULL;
3707 
3708 	if (addr)
3709 		pfx = nla_data(addr);
3710 
3711 	if (local) {
3712 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3713 			*peer_pfx = pfx;
3714 		pfx = nla_data(local);
3715 	}
3716 
3717 	return pfx;
3718 }
3719 
3720 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3721 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3722 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3723 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3724 	[IFA_FLAGS]		= { .len = sizeof(u32) },
3725 };
3726 
3727 static int
3728 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
3729 {
3730 	struct net *net = sock_net(skb->sk);
3731 	struct ifaddrmsg *ifm;
3732 	struct nlattr *tb[IFA_MAX+1];
3733 	struct in6_addr *pfx, *peer_pfx;
3734 	u32 ifa_flags;
3735 	int err;
3736 
3737 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3738 	if (err < 0)
3739 		return err;
3740 
3741 	ifm = nlmsg_data(nlh);
3742 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3743 	if (pfx == NULL)
3744 		return -EINVAL;
3745 
3746 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3747 
3748 	/* We ignore other flags so far. */
3749 	ifa_flags &= IFA_F_MANAGETEMPADDR;
3750 
3751 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
3752 			      ifm->ifa_prefixlen);
3753 }
3754 
3755 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
3756 			     u32 prefered_lft, u32 valid_lft)
3757 {
3758 	u32 flags;
3759 	clock_t expires;
3760 	unsigned long timeout;
3761 	bool was_managetempaddr;
3762 	bool had_prefixroute;
3763 
3764 	ASSERT_RTNL();
3765 
3766 	if (!valid_lft || (prefered_lft > valid_lft))
3767 		return -EINVAL;
3768 
3769 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
3770 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
3771 		return -EINVAL;
3772 
3773 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3774 	if (addrconf_finite_timeout(timeout)) {
3775 		expires = jiffies_to_clock_t(timeout * HZ);
3776 		valid_lft = timeout;
3777 		flags = RTF_EXPIRES;
3778 	} else {
3779 		expires = 0;
3780 		flags = 0;
3781 		ifa_flags |= IFA_F_PERMANENT;
3782 	}
3783 
3784 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3785 	if (addrconf_finite_timeout(timeout)) {
3786 		if (timeout == 0)
3787 			ifa_flags |= IFA_F_DEPRECATED;
3788 		prefered_lft = timeout;
3789 	}
3790 
3791 	spin_lock_bh(&ifp->lock);
3792 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
3793 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
3794 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
3795 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
3796 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3797 			IFA_F_NOPREFIXROUTE);
3798 	ifp->flags |= ifa_flags;
3799 	ifp->tstamp = jiffies;
3800 	ifp->valid_lft = valid_lft;
3801 	ifp->prefered_lft = prefered_lft;
3802 
3803 	spin_unlock_bh(&ifp->lock);
3804 	if (!(ifp->flags&IFA_F_TENTATIVE))
3805 		ipv6_ifa_notify(0, ifp);
3806 
3807 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
3808 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3809 				      expires, flags);
3810 	} else if (had_prefixroute) {
3811 		enum cleanup_prefix_rt_t action;
3812 		unsigned long rt_expires;
3813 
3814 		write_lock_bh(&ifp->idev->lock);
3815 		action = check_cleanup_prefix_route(ifp, &rt_expires);
3816 		write_unlock_bh(&ifp->idev->lock);
3817 
3818 		if (action != CLEANUP_PREFIX_RT_NOP) {
3819 			cleanup_prefix_route(ifp, rt_expires,
3820 				action == CLEANUP_PREFIX_RT_DEL);
3821 		}
3822 	}
3823 
3824 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
3825 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
3826 			valid_lft = prefered_lft = 0;
3827 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
3828 				 !was_managetempaddr, jiffies);
3829 	}
3830 
3831 	addrconf_verify_rtnl();
3832 
3833 	return 0;
3834 }
3835 
3836 static int
3837 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
3838 {
3839 	struct net *net = sock_net(skb->sk);
3840 	struct ifaddrmsg *ifm;
3841 	struct nlattr *tb[IFA_MAX+1];
3842 	struct in6_addr *pfx, *peer_pfx;
3843 	struct inet6_ifaddr *ifa;
3844 	struct net_device *dev;
3845 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3846 	u32 ifa_flags;
3847 	int err;
3848 
3849 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3850 	if (err < 0)
3851 		return err;
3852 
3853 	ifm = nlmsg_data(nlh);
3854 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
3855 	if (pfx == NULL)
3856 		return -EINVAL;
3857 
3858 	if (tb[IFA_CACHEINFO]) {
3859 		struct ifa_cacheinfo *ci;
3860 
3861 		ci = nla_data(tb[IFA_CACHEINFO]);
3862 		valid_lft = ci->ifa_valid;
3863 		preferred_lft = ci->ifa_prefered;
3864 	} else {
3865 		preferred_lft = INFINITY_LIFE_TIME;
3866 		valid_lft = INFINITY_LIFE_TIME;
3867 	}
3868 
3869 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3870 	if (dev == NULL)
3871 		return -ENODEV;
3872 
3873 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
3874 
3875 	/* We ignore other flags so far. */
3876 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
3877 		     IFA_F_NOPREFIXROUTE;
3878 
3879 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3880 	if (ifa == NULL) {
3881 		/*
3882 		 * It would be best to check for !NLM_F_CREATE here but
3883 		 * userspace already relies on not having to provide this.
3884 		 */
3885 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
3886 				      ifm->ifa_prefixlen, ifa_flags,
3887 				      preferred_lft, valid_lft);
3888 	}
3889 
3890 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3891 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3892 		err = -EEXIST;
3893 	else
3894 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3895 
3896 	in6_ifa_put(ifa);
3897 
3898 	return err;
3899 }
3900 
3901 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
3902 			  u8 scope, int ifindex)
3903 {
3904 	struct ifaddrmsg *ifm;
3905 
3906 	ifm = nlmsg_data(nlh);
3907 	ifm->ifa_family = AF_INET6;
3908 	ifm->ifa_prefixlen = prefixlen;
3909 	ifm->ifa_flags = flags;
3910 	ifm->ifa_scope = scope;
3911 	ifm->ifa_index = ifindex;
3912 }
3913 
3914 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3915 			 unsigned long tstamp, u32 preferred, u32 valid)
3916 {
3917 	struct ifa_cacheinfo ci;
3918 
3919 	ci.cstamp = cstamp_delta(cstamp);
3920 	ci.tstamp = cstamp_delta(tstamp);
3921 	ci.ifa_prefered = preferred;
3922 	ci.ifa_valid = valid;
3923 
3924 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3925 }
3926 
3927 static inline int rt_scope(int ifa_scope)
3928 {
3929 	if (ifa_scope & IFA_HOST)
3930 		return RT_SCOPE_HOST;
3931 	else if (ifa_scope & IFA_LINK)
3932 		return RT_SCOPE_LINK;
3933 	else if (ifa_scope & IFA_SITE)
3934 		return RT_SCOPE_SITE;
3935 	else
3936 		return RT_SCOPE_UNIVERSE;
3937 }
3938 
3939 static inline int inet6_ifaddr_msgsize(void)
3940 {
3941 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3942 	       + nla_total_size(16) /* IFA_LOCAL */
3943 	       + nla_total_size(16) /* IFA_ADDRESS */
3944 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
3945 	       + nla_total_size(4)  /* IFA_FLAGS */;
3946 }
3947 
3948 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3949 			     u32 portid, u32 seq, int event, unsigned int flags)
3950 {
3951 	struct nlmsghdr  *nlh;
3952 	u32 preferred, valid;
3953 
3954 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3955 	if (nlh == NULL)
3956 		return -EMSGSIZE;
3957 
3958 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3959 		      ifa->idev->dev->ifindex);
3960 
3961 	if (!((ifa->flags&IFA_F_PERMANENT) &&
3962 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
3963 		preferred = ifa->prefered_lft;
3964 		valid = ifa->valid_lft;
3965 		if (preferred != INFINITY_LIFE_TIME) {
3966 			long tval = (jiffies - ifa->tstamp)/HZ;
3967 			if (preferred > tval)
3968 				preferred -= tval;
3969 			else
3970 				preferred = 0;
3971 			if (valid != INFINITY_LIFE_TIME) {
3972 				if (valid > tval)
3973 					valid -= tval;
3974 				else
3975 					valid = 0;
3976 			}
3977 		}
3978 	} else {
3979 		preferred = INFINITY_LIFE_TIME;
3980 		valid = INFINITY_LIFE_TIME;
3981 	}
3982 
3983 	if (!ipv6_addr_any(&ifa->peer_addr)) {
3984 		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||
3985 		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)
3986 			goto error;
3987 	} else
3988 		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)
3989 			goto error;
3990 
3991 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
3992 		goto error;
3993 
3994 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
3995 		goto error;
3996 
3997 	return nlmsg_end(skb, nlh);
3998 
3999 error:
4000 	nlmsg_cancel(skb, nlh);
4001 	return -EMSGSIZE;
4002 }
4003 
4004 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4005 				u32 portid, u32 seq, int event, u16 flags)
4006 {
4007 	struct nlmsghdr  *nlh;
4008 	u8 scope = RT_SCOPE_UNIVERSE;
4009 	int ifindex = ifmca->idev->dev->ifindex;
4010 
4011 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4012 		scope = RT_SCOPE_SITE;
4013 
4014 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4015 	if (nlh == NULL)
4016 		return -EMSGSIZE;
4017 
4018 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4019 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
4020 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4021 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4022 		nlmsg_cancel(skb, nlh);
4023 		return -EMSGSIZE;
4024 	}
4025 
4026 	return nlmsg_end(skb, nlh);
4027 }
4028 
4029 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4030 				u32 portid, u32 seq, int event, unsigned int flags)
4031 {
4032 	struct nlmsghdr  *nlh;
4033 	u8 scope = RT_SCOPE_UNIVERSE;
4034 	int ifindex = ifaca->aca_idev->dev->ifindex;
4035 
4036 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4037 		scope = RT_SCOPE_SITE;
4038 
4039 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4040 	if (nlh == NULL)
4041 		return -EMSGSIZE;
4042 
4043 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4044 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
4045 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4046 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4047 		nlmsg_cancel(skb, nlh);
4048 		return -EMSGSIZE;
4049 	}
4050 
4051 	return nlmsg_end(skb, nlh);
4052 }
4053 
4054 enum addr_type_t {
4055 	UNICAST_ADDR,
4056 	MULTICAST_ADDR,
4057 	ANYCAST_ADDR,
4058 };
4059 
4060 /* called with rcu_read_lock() */
4061 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4062 			  struct netlink_callback *cb, enum addr_type_t type,
4063 			  int s_ip_idx, int *p_ip_idx)
4064 {
4065 	struct ifmcaddr6 *ifmca;
4066 	struct ifacaddr6 *ifaca;
4067 	int err = 1;
4068 	int ip_idx = *p_ip_idx;
4069 
4070 	read_lock_bh(&idev->lock);
4071 	switch (type) {
4072 	case UNICAST_ADDR: {
4073 		struct inet6_ifaddr *ifa;
4074 
4075 		/* unicast address incl. temp addr */
4076 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4077 			if (++ip_idx < s_ip_idx)
4078 				continue;
4079 			err = inet6_fill_ifaddr(skb, ifa,
4080 						NETLINK_CB(cb->skb).portid,
4081 						cb->nlh->nlmsg_seq,
4082 						RTM_NEWADDR,
4083 						NLM_F_MULTI);
4084 			if (err <= 0)
4085 				break;
4086 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4087 		}
4088 		break;
4089 	}
4090 	case MULTICAST_ADDR:
4091 		/* multicast address */
4092 		for (ifmca = idev->mc_list; ifmca;
4093 		     ifmca = ifmca->next, ip_idx++) {
4094 			if (ip_idx < s_ip_idx)
4095 				continue;
4096 			err = inet6_fill_ifmcaddr(skb, ifmca,
4097 						  NETLINK_CB(cb->skb).portid,
4098 						  cb->nlh->nlmsg_seq,
4099 						  RTM_GETMULTICAST,
4100 						  NLM_F_MULTI);
4101 			if (err <= 0)
4102 				break;
4103 		}
4104 		break;
4105 	case ANYCAST_ADDR:
4106 		/* anycast address */
4107 		for (ifaca = idev->ac_list; ifaca;
4108 		     ifaca = ifaca->aca_next, ip_idx++) {
4109 			if (ip_idx < s_ip_idx)
4110 				continue;
4111 			err = inet6_fill_ifacaddr(skb, ifaca,
4112 						  NETLINK_CB(cb->skb).portid,
4113 						  cb->nlh->nlmsg_seq,
4114 						  RTM_GETANYCAST,
4115 						  NLM_F_MULTI);
4116 			if (err <= 0)
4117 				break;
4118 		}
4119 		break;
4120 	default:
4121 		break;
4122 	}
4123 	read_unlock_bh(&idev->lock);
4124 	*p_ip_idx = ip_idx;
4125 	return err;
4126 }
4127 
4128 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4129 			   enum addr_type_t type)
4130 {
4131 	struct net *net = sock_net(skb->sk);
4132 	int h, s_h;
4133 	int idx, ip_idx;
4134 	int s_idx, s_ip_idx;
4135 	struct net_device *dev;
4136 	struct inet6_dev *idev;
4137 	struct hlist_head *head;
4138 
4139 	s_h = cb->args[0];
4140 	s_idx = idx = cb->args[1];
4141 	s_ip_idx = ip_idx = cb->args[2];
4142 
4143 	rcu_read_lock();
4144 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4145 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4146 		idx = 0;
4147 		head = &net->dev_index_head[h];
4148 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4149 			if (idx < s_idx)
4150 				goto cont;
4151 			if (h > s_h || idx > s_idx)
4152 				s_ip_idx = 0;
4153 			ip_idx = 0;
4154 			idev = __in6_dev_get(dev);
4155 			if (!idev)
4156 				goto cont;
4157 
4158 			if (in6_dump_addrs(idev, skb, cb, type,
4159 					   s_ip_idx, &ip_idx) <= 0)
4160 				goto done;
4161 cont:
4162 			idx++;
4163 		}
4164 	}
4165 done:
4166 	rcu_read_unlock();
4167 	cb->args[0] = h;
4168 	cb->args[1] = idx;
4169 	cb->args[2] = ip_idx;
4170 
4171 	return skb->len;
4172 }
4173 
4174 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4175 {
4176 	enum addr_type_t type = UNICAST_ADDR;
4177 
4178 	return inet6_dump_addr(skb, cb, type);
4179 }
4180 
4181 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4182 {
4183 	enum addr_type_t type = MULTICAST_ADDR;
4184 
4185 	return inet6_dump_addr(skb, cb, type);
4186 }
4187 
4188 
4189 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4190 {
4191 	enum addr_type_t type = ANYCAST_ADDR;
4192 
4193 	return inet6_dump_addr(skb, cb, type);
4194 }
4195 
4196 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh)
4197 {
4198 	struct net *net = sock_net(in_skb->sk);
4199 	struct ifaddrmsg *ifm;
4200 	struct nlattr *tb[IFA_MAX+1];
4201 	struct in6_addr *addr = NULL, *peer;
4202 	struct net_device *dev = NULL;
4203 	struct inet6_ifaddr *ifa;
4204 	struct sk_buff *skb;
4205 	int err;
4206 
4207 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
4208 	if (err < 0)
4209 		goto errout;
4210 
4211 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4212 	if (addr == NULL) {
4213 		err = -EINVAL;
4214 		goto errout;
4215 	}
4216 
4217 	ifm = nlmsg_data(nlh);
4218 	if (ifm->ifa_index)
4219 		dev = __dev_get_by_index(net, ifm->ifa_index);
4220 
4221 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4222 	if (!ifa) {
4223 		err = -EADDRNOTAVAIL;
4224 		goto errout;
4225 	}
4226 
4227 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4228 	if (!skb) {
4229 		err = -ENOBUFS;
4230 		goto errout_ifa;
4231 	}
4232 
4233 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4234 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4235 	if (err < 0) {
4236 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4237 		WARN_ON(err == -EMSGSIZE);
4238 		kfree_skb(skb);
4239 		goto errout_ifa;
4240 	}
4241 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4242 errout_ifa:
4243 	in6_ifa_put(ifa);
4244 errout:
4245 	return err;
4246 }
4247 
4248 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4249 {
4250 	struct sk_buff *skb;
4251 	struct net *net = dev_net(ifa->idev->dev);
4252 	int err = -ENOBUFS;
4253 
4254 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4255 	if (skb == NULL)
4256 		goto errout;
4257 
4258 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4259 	if (err < 0) {
4260 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4261 		WARN_ON(err == -EMSGSIZE);
4262 		kfree_skb(skb);
4263 		goto errout;
4264 	}
4265 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4266 	return;
4267 errout:
4268 	if (err < 0)
4269 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4270 }
4271 
4272 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4273 				__s32 *array, int bytes)
4274 {
4275 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4276 
4277 	memset(array, 0, bytes);
4278 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4279 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4280 	array[DEVCONF_MTU6] = cnf->mtu6;
4281 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4282 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4283 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4284 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4285 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4286 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4287 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4288 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4289 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4290 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4291 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4292 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4293 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4294 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4295 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4296 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4297 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4298 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4299 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4300 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4301 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4302 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4303 #ifdef CONFIG_IPV6_ROUTER_PREF
4304 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4305 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4306 		jiffies_to_msecs(cnf->rtr_probe_interval);
4307 #ifdef CONFIG_IPV6_ROUTE_INFO
4308 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4309 #endif
4310 #endif
4311 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4312 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4313 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4314 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4315 #endif
4316 #ifdef CONFIG_IPV6_MROUTE
4317 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4318 #endif
4319 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4320 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4321 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4322 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4323 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
4324 }
4325 
4326 static inline size_t inet6_ifla6_size(void)
4327 {
4328 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4329 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4330 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4331 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4332 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
4333 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
4334 }
4335 
4336 static inline size_t inet6_if_nlmsg_size(void)
4337 {
4338 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4339 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4340 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4341 	       + nla_total_size(4) /* IFLA_MTU */
4342 	       + nla_total_size(4) /* IFLA_LINK */
4343 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4344 }
4345 
4346 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4347 				      int items, int bytes)
4348 {
4349 	int i;
4350 	int pad = bytes - sizeof(u64) * items;
4351 	BUG_ON(pad < 0);
4352 
4353 	/* Use put_unaligned() because stats may not be aligned for u64. */
4354 	put_unaligned(items, &stats[0]);
4355 	for (i = 1; i < items; i++)
4356 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4357 
4358 	memset(&stats[items], 0, pad);
4359 }
4360 
4361 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
4362 				      int items, int bytes, size_t syncpoff)
4363 {
4364 	int i;
4365 	int pad = bytes - sizeof(u64) * items;
4366 	BUG_ON(pad < 0);
4367 
4368 	/* Use put_unaligned() because stats may not be aligned for u64. */
4369 	put_unaligned(items, &stats[0]);
4370 	for (i = 1; i < items; i++)
4371 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4372 
4373 	memset(&stats[items], 0, pad);
4374 }
4375 
4376 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4377 			     int bytes)
4378 {
4379 	switch (attrtype) {
4380 	case IFLA_INET6_STATS:
4381 		__snmp6_fill_stats64(stats, idev->stats.ipv6,
4382 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4383 		break;
4384 	case IFLA_INET6_ICMP6STATS:
4385 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4386 		break;
4387 	}
4388 }
4389 
4390 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4391 {
4392 	struct nlattr *nla;
4393 	struct ifla_cacheinfo ci;
4394 
4395 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4396 		goto nla_put_failure;
4397 	ci.max_reasm_len = IPV6_MAXPLEN;
4398 	ci.tstamp = cstamp_delta(idev->tstamp);
4399 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4400 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
4401 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4402 		goto nla_put_failure;
4403 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4404 	if (nla == NULL)
4405 		goto nla_put_failure;
4406 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4407 
4408 	/* XXX - MC not implemented */
4409 
4410 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4411 	if (nla == NULL)
4412 		goto nla_put_failure;
4413 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4414 
4415 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4416 	if (nla == NULL)
4417 		goto nla_put_failure;
4418 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4419 
4420 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
4421 	if (nla == NULL)
4422 		goto nla_put_failure;
4423 	read_lock_bh(&idev->lock);
4424 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
4425 	read_unlock_bh(&idev->lock);
4426 
4427 	return 0;
4428 
4429 nla_put_failure:
4430 	return -EMSGSIZE;
4431 }
4432 
4433 static size_t inet6_get_link_af_size(const struct net_device *dev)
4434 {
4435 	if (!__in6_dev_get(dev))
4436 		return 0;
4437 
4438 	return inet6_ifla6_size();
4439 }
4440 
4441 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4442 {
4443 	struct inet6_dev *idev = __in6_dev_get(dev);
4444 
4445 	if (!idev)
4446 		return -ENODATA;
4447 
4448 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4449 		return -EMSGSIZE;
4450 
4451 	return 0;
4452 }
4453 
4454 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
4455 {
4456 	struct inet6_ifaddr *ifp;
4457 	struct net_device *dev = idev->dev;
4458 	bool update_rs = false;
4459 	struct in6_addr ll_addr;
4460 
4461 	ASSERT_RTNL();
4462 
4463 	if (token == NULL)
4464 		return -EINVAL;
4465 	if (ipv6_addr_any(token))
4466 		return -EINVAL;
4467 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
4468 		return -EINVAL;
4469 	if (!ipv6_accept_ra(idev))
4470 		return -EINVAL;
4471 	if (idev->cnf.rtr_solicits <= 0)
4472 		return -EINVAL;
4473 
4474 	write_lock_bh(&idev->lock);
4475 
4476 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
4477 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
4478 
4479 	write_unlock_bh(&idev->lock);
4480 
4481 	if (!idev->dead && (idev->if_flags & IF_READY) &&
4482 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
4483 			     IFA_F_OPTIMISTIC)) {
4484 
4485 		/* If we're not ready, then normal ifup will take care
4486 		 * of this. Otherwise, we need to request our rs here.
4487 		 */
4488 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
4489 		update_rs = true;
4490 	}
4491 
4492 	write_lock_bh(&idev->lock);
4493 
4494 	if (update_rs) {
4495 		idev->if_flags |= IF_RS_SENT;
4496 		idev->rs_probes = 1;
4497 		addrconf_mod_rs_timer(idev, idev->cnf.rtr_solicit_interval);
4498 	}
4499 
4500 	/* Well, that's kinda nasty ... */
4501 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4502 		spin_lock(&ifp->lock);
4503 		if (ifp->tokenized) {
4504 			ifp->valid_lft = 0;
4505 			ifp->prefered_lft = 0;
4506 		}
4507 		spin_unlock(&ifp->lock);
4508 	}
4509 
4510 	write_unlock_bh(&idev->lock);
4511 	addrconf_verify_rtnl();
4512 	return 0;
4513 }
4514 
4515 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
4516 {
4517 	int err = -EINVAL;
4518 	struct inet6_dev *idev = __in6_dev_get(dev);
4519 	struct nlattr *tb[IFLA_INET6_MAX + 1];
4520 
4521 	if (!idev)
4522 		return -EAFNOSUPPORT;
4523 
4524 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL) < 0)
4525 		BUG();
4526 
4527 	if (tb[IFLA_INET6_TOKEN])
4528 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
4529 
4530 	return err;
4531 }
4532 
4533 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4534 			     u32 portid, u32 seq, int event, unsigned int flags)
4535 {
4536 	struct net_device *dev = idev->dev;
4537 	struct ifinfomsg *hdr;
4538 	struct nlmsghdr *nlh;
4539 	void *protoinfo;
4540 
4541 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4542 	if (nlh == NULL)
4543 		return -EMSGSIZE;
4544 
4545 	hdr = nlmsg_data(nlh);
4546 	hdr->ifi_family = AF_INET6;
4547 	hdr->__ifi_pad = 0;
4548 	hdr->ifi_type = dev->type;
4549 	hdr->ifi_index = dev->ifindex;
4550 	hdr->ifi_flags = dev_get_flags(dev);
4551 	hdr->ifi_change = 0;
4552 
4553 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4554 	    (dev->addr_len &&
4555 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4556 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4557 	    (dev->ifindex != dev->iflink &&
4558 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4559 		goto nla_put_failure;
4560 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4561 	if (protoinfo == NULL)
4562 		goto nla_put_failure;
4563 
4564 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4565 		goto nla_put_failure;
4566 
4567 	nla_nest_end(skb, protoinfo);
4568 	return nlmsg_end(skb, nlh);
4569 
4570 nla_put_failure:
4571 	nlmsg_cancel(skb, nlh);
4572 	return -EMSGSIZE;
4573 }
4574 
4575 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4576 {
4577 	struct net *net = sock_net(skb->sk);
4578 	int h, s_h;
4579 	int idx = 0, s_idx;
4580 	struct net_device *dev;
4581 	struct inet6_dev *idev;
4582 	struct hlist_head *head;
4583 
4584 	s_h = cb->args[0];
4585 	s_idx = cb->args[1];
4586 
4587 	rcu_read_lock();
4588 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4589 		idx = 0;
4590 		head = &net->dev_index_head[h];
4591 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4592 			if (idx < s_idx)
4593 				goto cont;
4594 			idev = __in6_dev_get(dev);
4595 			if (!idev)
4596 				goto cont;
4597 			if (inet6_fill_ifinfo(skb, idev,
4598 					      NETLINK_CB(cb->skb).portid,
4599 					      cb->nlh->nlmsg_seq,
4600 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4601 				goto out;
4602 cont:
4603 			idx++;
4604 		}
4605 	}
4606 out:
4607 	rcu_read_unlock();
4608 	cb->args[1] = idx;
4609 	cb->args[0] = h;
4610 
4611 	return skb->len;
4612 }
4613 
4614 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4615 {
4616 	struct sk_buff *skb;
4617 	struct net *net = dev_net(idev->dev);
4618 	int err = -ENOBUFS;
4619 
4620 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4621 	if (skb == NULL)
4622 		goto errout;
4623 
4624 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4625 	if (err < 0) {
4626 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4627 		WARN_ON(err == -EMSGSIZE);
4628 		kfree_skb(skb);
4629 		goto errout;
4630 	}
4631 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4632 	return;
4633 errout:
4634 	if (err < 0)
4635 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4636 }
4637 
4638 static inline size_t inet6_prefix_nlmsg_size(void)
4639 {
4640 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4641 	       + nla_total_size(sizeof(struct in6_addr))
4642 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4643 }
4644 
4645 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4646 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4647 			     int event, unsigned int flags)
4648 {
4649 	struct prefixmsg *pmsg;
4650 	struct nlmsghdr *nlh;
4651 	struct prefix_cacheinfo	ci;
4652 
4653 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4654 	if (nlh == NULL)
4655 		return -EMSGSIZE;
4656 
4657 	pmsg = nlmsg_data(nlh);
4658 	pmsg->prefix_family = AF_INET6;
4659 	pmsg->prefix_pad1 = 0;
4660 	pmsg->prefix_pad2 = 0;
4661 	pmsg->prefix_ifindex = idev->dev->ifindex;
4662 	pmsg->prefix_len = pinfo->prefix_len;
4663 	pmsg->prefix_type = pinfo->type;
4664 	pmsg->prefix_pad3 = 0;
4665 	pmsg->prefix_flags = 0;
4666 	if (pinfo->onlink)
4667 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4668 	if (pinfo->autoconf)
4669 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4670 
4671 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4672 		goto nla_put_failure;
4673 	ci.preferred_time = ntohl(pinfo->prefered);
4674 	ci.valid_time = ntohl(pinfo->valid);
4675 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4676 		goto nla_put_failure;
4677 	return nlmsg_end(skb, nlh);
4678 
4679 nla_put_failure:
4680 	nlmsg_cancel(skb, nlh);
4681 	return -EMSGSIZE;
4682 }
4683 
4684 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4685 			 struct prefix_info *pinfo)
4686 {
4687 	struct sk_buff *skb;
4688 	struct net *net = dev_net(idev->dev);
4689 	int err = -ENOBUFS;
4690 
4691 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4692 	if (skb == NULL)
4693 		goto errout;
4694 
4695 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4696 	if (err < 0) {
4697 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4698 		WARN_ON(err == -EMSGSIZE);
4699 		kfree_skb(skb);
4700 		goto errout;
4701 	}
4702 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4703 	return;
4704 errout:
4705 	if (err < 0)
4706 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4707 }
4708 
4709 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4710 {
4711 	struct net *net = dev_net(ifp->idev->dev);
4712 
4713 	if (event)
4714 		ASSERT_RTNL();
4715 
4716 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4717 
4718 	switch (event) {
4719 	case RTM_NEWADDR:
4720 		/*
4721 		 * If the address was optimistic
4722 		 * we inserted the route at the start of
4723 		 * our DAD process, so we don't need
4724 		 * to do it again
4725 		 */
4726 		if (!(ifp->rt->rt6i_node))
4727 			ip6_ins_rt(ifp->rt);
4728 		if (ifp->idev->cnf.forwarding)
4729 			addrconf_join_anycast(ifp);
4730 		if (!ipv6_addr_any(&ifp->peer_addr))
4731 			addrconf_prefix_route(&ifp->peer_addr, 128,
4732 					      ifp->idev->dev, 0, 0);
4733 		break;
4734 	case RTM_DELADDR:
4735 		if (ifp->idev->cnf.forwarding)
4736 			addrconf_leave_anycast(ifp);
4737 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4738 		if (!ipv6_addr_any(&ifp->peer_addr)) {
4739 			struct rt6_info *rt;
4740 			struct net_device *dev = ifp->idev->dev;
4741 
4742 			rt = rt6_lookup(dev_net(dev), &ifp->peer_addr, NULL,
4743 					dev->ifindex, 1);
4744 			if (rt) {
4745 				dst_hold(&rt->dst);
4746 				if (ip6_del_rt(rt))
4747 					dst_free(&rt->dst);
4748 			}
4749 		}
4750 		dst_hold(&ifp->rt->dst);
4751 
4752 		if (ip6_del_rt(ifp->rt))
4753 			dst_free(&ifp->rt->dst);
4754 		break;
4755 	}
4756 	atomic_inc(&net->ipv6.dev_addr_genid);
4757 	rt_genid_bump_ipv6(net);
4758 }
4759 
4760 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4761 {
4762 	rcu_read_lock_bh();
4763 	if (likely(ifp->idev->dead == 0))
4764 		__ipv6_ifa_notify(event, ifp);
4765 	rcu_read_unlock_bh();
4766 }
4767 
4768 #ifdef CONFIG_SYSCTL
4769 
4770 static
4771 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
4772 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4773 {
4774 	int *valp = ctl->data;
4775 	int val = *valp;
4776 	loff_t pos = *ppos;
4777 	struct ctl_table lctl;
4778 	int ret;
4779 
4780 	/*
4781 	 * ctl->data points to idev->cnf.forwarding, we should
4782 	 * not modify it until we get the rtnl lock.
4783 	 */
4784 	lctl = *ctl;
4785 	lctl.data = &val;
4786 
4787 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4788 
4789 	if (write)
4790 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4791 	if (ret)
4792 		*ppos = pos;
4793 	return ret;
4794 }
4795 
4796 static void dev_disable_change(struct inet6_dev *idev)
4797 {
4798 	struct netdev_notifier_info info;
4799 
4800 	if (!idev || !idev->dev)
4801 		return;
4802 
4803 	netdev_notifier_info_init(&info, idev->dev);
4804 	if (idev->cnf.disable_ipv6)
4805 		addrconf_notify(NULL, NETDEV_DOWN, &info);
4806 	else
4807 		addrconf_notify(NULL, NETDEV_UP, &info);
4808 }
4809 
4810 static void addrconf_disable_change(struct net *net, __s32 newf)
4811 {
4812 	struct net_device *dev;
4813 	struct inet6_dev *idev;
4814 
4815 	rcu_read_lock();
4816 	for_each_netdev_rcu(net, dev) {
4817 		idev = __in6_dev_get(dev);
4818 		if (idev) {
4819 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4820 			idev->cnf.disable_ipv6 = newf;
4821 			if (changed)
4822 				dev_disable_change(idev);
4823 		}
4824 	}
4825 	rcu_read_unlock();
4826 }
4827 
4828 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4829 {
4830 	struct net *net;
4831 	int old;
4832 
4833 	if (!rtnl_trylock())
4834 		return restart_syscall();
4835 
4836 	net = (struct net *)table->extra2;
4837 	old = *p;
4838 	*p = newf;
4839 
4840 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4841 		rtnl_unlock();
4842 		return 0;
4843 	}
4844 
4845 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4846 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4847 		addrconf_disable_change(net, newf);
4848 	} else if ((!newf) ^ (!old))
4849 		dev_disable_change((struct inet6_dev *)table->extra1);
4850 
4851 	rtnl_unlock();
4852 	return 0;
4853 }
4854 
4855 static
4856 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
4857 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4858 {
4859 	int *valp = ctl->data;
4860 	int val = *valp;
4861 	loff_t pos = *ppos;
4862 	struct ctl_table lctl;
4863 	int ret;
4864 
4865 	/*
4866 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4867 	 * not modify it until we get the rtnl lock.
4868 	 */
4869 	lctl = *ctl;
4870 	lctl.data = &val;
4871 
4872 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4873 
4874 	if (write)
4875 		ret = addrconf_disable_ipv6(ctl, valp, val);
4876 	if (ret)
4877 		*ppos = pos;
4878 	return ret;
4879 }
4880 
4881 static
4882 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
4883 			      void __user *buffer, size_t *lenp, loff_t *ppos)
4884 {
4885 	int *valp = ctl->data;
4886 	int ret;
4887 	int old, new;
4888 
4889 	old = *valp;
4890 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
4891 	new = *valp;
4892 
4893 	if (write && old != new) {
4894 		struct net *net = ctl->extra2;
4895 
4896 		if (!rtnl_trylock())
4897 			return restart_syscall();
4898 
4899 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
4900 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4901 						     NETCONFA_IFINDEX_DEFAULT,
4902 						     net->ipv6.devconf_dflt);
4903 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
4904 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4905 						     NETCONFA_IFINDEX_ALL,
4906 						     net->ipv6.devconf_all);
4907 		else {
4908 			struct inet6_dev *idev = ctl->extra1;
4909 
4910 			inet6_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
4911 						     idev->dev->ifindex,
4912 						     &idev->cnf);
4913 		}
4914 		rtnl_unlock();
4915 	}
4916 
4917 	return ret;
4918 }
4919 
4920 
4921 static struct addrconf_sysctl_table
4922 {
4923 	struct ctl_table_header *sysctl_header;
4924 	struct ctl_table addrconf_vars[DEVCONF_MAX+1];
4925 } addrconf_sysctl __read_mostly = {
4926 	.sysctl_header = NULL,
4927 	.addrconf_vars = {
4928 		{
4929 			.procname	= "forwarding",
4930 			.data		= &ipv6_devconf.forwarding,
4931 			.maxlen		= sizeof(int),
4932 			.mode		= 0644,
4933 			.proc_handler	= addrconf_sysctl_forward,
4934 		},
4935 		{
4936 			.procname	= "hop_limit",
4937 			.data		= &ipv6_devconf.hop_limit,
4938 			.maxlen		= sizeof(int),
4939 			.mode		= 0644,
4940 			.proc_handler	= proc_dointvec,
4941 		},
4942 		{
4943 			.procname	= "mtu",
4944 			.data		= &ipv6_devconf.mtu6,
4945 			.maxlen		= sizeof(int),
4946 			.mode		= 0644,
4947 			.proc_handler	= proc_dointvec,
4948 		},
4949 		{
4950 			.procname	= "accept_ra",
4951 			.data		= &ipv6_devconf.accept_ra,
4952 			.maxlen		= sizeof(int),
4953 			.mode		= 0644,
4954 			.proc_handler	= proc_dointvec,
4955 		},
4956 		{
4957 			.procname	= "accept_redirects",
4958 			.data		= &ipv6_devconf.accept_redirects,
4959 			.maxlen		= sizeof(int),
4960 			.mode		= 0644,
4961 			.proc_handler	= proc_dointvec,
4962 		},
4963 		{
4964 			.procname	= "autoconf",
4965 			.data		= &ipv6_devconf.autoconf,
4966 			.maxlen		= sizeof(int),
4967 			.mode		= 0644,
4968 			.proc_handler	= proc_dointvec,
4969 		},
4970 		{
4971 			.procname	= "dad_transmits",
4972 			.data		= &ipv6_devconf.dad_transmits,
4973 			.maxlen		= sizeof(int),
4974 			.mode		= 0644,
4975 			.proc_handler	= proc_dointvec,
4976 		},
4977 		{
4978 			.procname	= "router_solicitations",
4979 			.data		= &ipv6_devconf.rtr_solicits,
4980 			.maxlen		= sizeof(int),
4981 			.mode		= 0644,
4982 			.proc_handler	= proc_dointvec,
4983 		},
4984 		{
4985 			.procname	= "router_solicitation_interval",
4986 			.data		= &ipv6_devconf.rtr_solicit_interval,
4987 			.maxlen		= sizeof(int),
4988 			.mode		= 0644,
4989 			.proc_handler	= proc_dointvec_jiffies,
4990 		},
4991 		{
4992 			.procname	= "router_solicitation_delay",
4993 			.data		= &ipv6_devconf.rtr_solicit_delay,
4994 			.maxlen		= sizeof(int),
4995 			.mode		= 0644,
4996 			.proc_handler	= proc_dointvec_jiffies,
4997 		},
4998 		{
4999 			.procname	= "force_mld_version",
5000 			.data		= &ipv6_devconf.force_mld_version,
5001 			.maxlen		= sizeof(int),
5002 			.mode		= 0644,
5003 			.proc_handler	= proc_dointvec,
5004 		},
5005 		{
5006 			.procname	= "mldv1_unsolicited_report_interval",
5007 			.data		=
5008 				&ipv6_devconf.mldv1_unsolicited_report_interval,
5009 			.maxlen		= sizeof(int),
5010 			.mode		= 0644,
5011 			.proc_handler	= proc_dointvec_ms_jiffies,
5012 		},
5013 		{
5014 			.procname	= "mldv2_unsolicited_report_interval",
5015 			.data		=
5016 				&ipv6_devconf.mldv2_unsolicited_report_interval,
5017 			.maxlen		= sizeof(int),
5018 			.mode		= 0644,
5019 			.proc_handler	= proc_dointvec_ms_jiffies,
5020 		},
5021 		{
5022 			.procname	= "use_tempaddr",
5023 			.data		= &ipv6_devconf.use_tempaddr,
5024 			.maxlen		= sizeof(int),
5025 			.mode		= 0644,
5026 			.proc_handler	= proc_dointvec,
5027 		},
5028 		{
5029 			.procname	= "temp_valid_lft",
5030 			.data		= &ipv6_devconf.temp_valid_lft,
5031 			.maxlen		= sizeof(int),
5032 			.mode		= 0644,
5033 			.proc_handler	= proc_dointvec,
5034 		},
5035 		{
5036 			.procname	= "temp_prefered_lft",
5037 			.data		= &ipv6_devconf.temp_prefered_lft,
5038 			.maxlen		= sizeof(int),
5039 			.mode		= 0644,
5040 			.proc_handler	= proc_dointvec,
5041 		},
5042 		{
5043 			.procname	= "regen_max_retry",
5044 			.data		= &ipv6_devconf.regen_max_retry,
5045 			.maxlen		= sizeof(int),
5046 			.mode		= 0644,
5047 			.proc_handler	= proc_dointvec,
5048 		},
5049 		{
5050 			.procname	= "max_desync_factor",
5051 			.data		= &ipv6_devconf.max_desync_factor,
5052 			.maxlen		= sizeof(int),
5053 			.mode		= 0644,
5054 			.proc_handler	= proc_dointvec,
5055 		},
5056 		{
5057 			.procname	= "max_addresses",
5058 			.data		= &ipv6_devconf.max_addresses,
5059 			.maxlen		= sizeof(int),
5060 			.mode		= 0644,
5061 			.proc_handler	= proc_dointvec,
5062 		},
5063 		{
5064 			.procname	= "accept_ra_defrtr",
5065 			.data		= &ipv6_devconf.accept_ra_defrtr,
5066 			.maxlen		= sizeof(int),
5067 			.mode		= 0644,
5068 			.proc_handler	= proc_dointvec,
5069 		},
5070 		{
5071 			.procname	= "accept_ra_pinfo",
5072 			.data		= &ipv6_devconf.accept_ra_pinfo,
5073 			.maxlen		= sizeof(int),
5074 			.mode		= 0644,
5075 			.proc_handler	= proc_dointvec,
5076 		},
5077 #ifdef CONFIG_IPV6_ROUTER_PREF
5078 		{
5079 			.procname	= "accept_ra_rtr_pref",
5080 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
5081 			.maxlen		= sizeof(int),
5082 			.mode		= 0644,
5083 			.proc_handler	= proc_dointvec,
5084 		},
5085 		{
5086 			.procname	= "router_probe_interval",
5087 			.data		= &ipv6_devconf.rtr_probe_interval,
5088 			.maxlen		= sizeof(int),
5089 			.mode		= 0644,
5090 			.proc_handler	= proc_dointvec_jiffies,
5091 		},
5092 #ifdef CONFIG_IPV6_ROUTE_INFO
5093 		{
5094 			.procname	= "accept_ra_rt_info_max_plen",
5095 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
5096 			.maxlen		= sizeof(int),
5097 			.mode		= 0644,
5098 			.proc_handler	= proc_dointvec,
5099 		},
5100 #endif
5101 #endif
5102 		{
5103 			.procname	= "proxy_ndp",
5104 			.data		= &ipv6_devconf.proxy_ndp,
5105 			.maxlen		= sizeof(int),
5106 			.mode		= 0644,
5107 			.proc_handler	= addrconf_sysctl_proxy_ndp,
5108 		},
5109 		{
5110 			.procname	= "accept_source_route",
5111 			.data		= &ipv6_devconf.accept_source_route,
5112 			.maxlen		= sizeof(int),
5113 			.mode		= 0644,
5114 			.proc_handler	= proc_dointvec,
5115 		},
5116 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5117 		{
5118 			.procname       = "optimistic_dad",
5119 			.data           = &ipv6_devconf.optimistic_dad,
5120 			.maxlen         = sizeof(int),
5121 			.mode           = 0644,
5122 			.proc_handler   = proc_dointvec,
5123 
5124 		},
5125 #endif
5126 #ifdef CONFIG_IPV6_MROUTE
5127 		{
5128 			.procname	= "mc_forwarding",
5129 			.data		= &ipv6_devconf.mc_forwarding,
5130 			.maxlen		= sizeof(int),
5131 			.mode		= 0444,
5132 			.proc_handler	= proc_dointvec,
5133 		},
5134 #endif
5135 		{
5136 			.procname	= "disable_ipv6",
5137 			.data		= &ipv6_devconf.disable_ipv6,
5138 			.maxlen		= sizeof(int),
5139 			.mode		= 0644,
5140 			.proc_handler	= addrconf_sysctl_disable,
5141 		},
5142 		{
5143 			.procname	= "accept_dad",
5144 			.data		= &ipv6_devconf.accept_dad,
5145 			.maxlen		= sizeof(int),
5146 			.mode		= 0644,
5147 			.proc_handler	= proc_dointvec,
5148 		},
5149 		{
5150 			.procname       = "force_tllao",
5151 			.data           = &ipv6_devconf.force_tllao,
5152 			.maxlen         = sizeof(int),
5153 			.mode           = 0644,
5154 			.proc_handler   = proc_dointvec
5155 		},
5156 		{
5157 			.procname       = "ndisc_notify",
5158 			.data           = &ipv6_devconf.ndisc_notify,
5159 			.maxlen         = sizeof(int),
5160 			.mode           = 0644,
5161 			.proc_handler   = proc_dointvec
5162 		},
5163 		{
5164 			.procname	= "suppress_frag_ndisc",
5165 			.data		= &ipv6_devconf.suppress_frag_ndisc,
5166 			.maxlen		= sizeof(int),
5167 			.mode		= 0644,
5168 			.proc_handler	= proc_dointvec
5169 		},
5170 		{
5171 			/* sentinel */
5172 		}
5173 	},
5174 };
5175 
5176 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
5177 		struct inet6_dev *idev, struct ipv6_devconf *p)
5178 {
5179 	int i;
5180 	struct addrconf_sysctl_table *t;
5181 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
5182 
5183 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
5184 	if (t == NULL)
5185 		goto out;
5186 
5187 	for (i = 0; t->addrconf_vars[i].data; i++) {
5188 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
5189 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
5190 		t->addrconf_vars[i].extra2 = net;
5191 	}
5192 
5193 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
5194 
5195 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
5196 	if (t->sysctl_header == NULL)
5197 		goto free;
5198 
5199 	p->sysctl = t;
5200 	return 0;
5201 
5202 free:
5203 	kfree(t);
5204 out:
5205 	return -ENOBUFS;
5206 }
5207 
5208 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
5209 {
5210 	struct addrconf_sysctl_table *t;
5211 
5212 	if (p->sysctl == NULL)
5213 		return;
5214 
5215 	t = p->sysctl;
5216 	p->sysctl = NULL;
5217 	unregister_net_sysctl_table(t->sysctl_header);
5218 	kfree(t);
5219 }
5220 
5221 static void addrconf_sysctl_register(struct inet6_dev *idev)
5222 {
5223 	neigh_sysctl_register(idev->dev, idev->nd_parms,
5224 			      &ndisc_ifinfo_sysctl_change);
5225 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
5226 					idev, &idev->cnf);
5227 }
5228 
5229 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
5230 {
5231 	__addrconf_sysctl_unregister(&idev->cnf);
5232 	neigh_sysctl_unregister(idev->nd_parms);
5233 }
5234 
5235 
5236 #endif
5237 
5238 static int __net_init addrconf_init_net(struct net *net)
5239 {
5240 	int err = -ENOMEM;
5241 	struct ipv6_devconf *all, *dflt;
5242 
5243 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
5244 	if (all == NULL)
5245 		goto err_alloc_all;
5246 
5247 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
5248 	if (dflt == NULL)
5249 		goto err_alloc_dflt;
5250 
5251 	/* these will be inherited by all namespaces */
5252 	dflt->autoconf = ipv6_defaults.autoconf;
5253 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
5254 
5255 	net->ipv6.devconf_all = all;
5256 	net->ipv6.devconf_dflt = dflt;
5257 
5258 #ifdef CONFIG_SYSCTL
5259 	err = __addrconf_sysctl_register(net, "all", NULL, all);
5260 	if (err < 0)
5261 		goto err_reg_all;
5262 
5263 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
5264 	if (err < 0)
5265 		goto err_reg_dflt;
5266 #endif
5267 	return 0;
5268 
5269 #ifdef CONFIG_SYSCTL
5270 err_reg_dflt:
5271 	__addrconf_sysctl_unregister(all);
5272 err_reg_all:
5273 	kfree(dflt);
5274 #endif
5275 err_alloc_dflt:
5276 	kfree(all);
5277 err_alloc_all:
5278 	return err;
5279 }
5280 
5281 static void __net_exit addrconf_exit_net(struct net *net)
5282 {
5283 #ifdef CONFIG_SYSCTL
5284 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
5285 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
5286 #endif
5287 	if (!net_eq(net, &init_net)) {
5288 		kfree(net->ipv6.devconf_dflt);
5289 		kfree(net->ipv6.devconf_all);
5290 	}
5291 }
5292 
5293 static struct pernet_operations addrconf_ops = {
5294 	.init = addrconf_init_net,
5295 	.exit = addrconf_exit_net,
5296 };
5297 
5298 static struct rtnl_af_ops inet6_ops = {
5299 	.family		  = AF_INET6,
5300 	.fill_link_af	  = inet6_fill_link_af,
5301 	.get_link_af_size = inet6_get_link_af_size,
5302 	.set_link_af	  = inet6_set_link_af,
5303 };
5304 
5305 /*
5306  *	Init / cleanup code
5307  */
5308 
5309 int __init addrconf_init(void)
5310 {
5311 	int i, err;
5312 
5313 	err = ipv6_addr_label_init();
5314 	if (err < 0) {
5315 		pr_crit("%s: cannot initialize default policy table: %d\n",
5316 			__func__, err);
5317 		goto out;
5318 	}
5319 
5320 	err = register_pernet_subsys(&addrconf_ops);
5321 	if (err < 0)
5322 		goto out_addrlabel;
5323 
5324 	addrconf_wq = create_workqueue("ipv6_addrconf");
5325 	if (!addrconf_wq) {
5326 		err = -ENOMEM;
5327 		goto out_nowq;
5328 	}
5329 
5330 	/* The addrconf netdev notifier requires that loopback_dev
5331 	 * has it's ipv6 private information allocated and setup
5332 	 * before it can bring up and give link-local addresses
5333 	 * to other devices which are up.
5334 	 *
5335 	 * Unfortunately, loopback_dev is not necessarily the first
5336 	 * entry in the global dev_base list of net devices.  In fact,
5337 	 * it is likely to be the very last entry on that list.
5338 	 * So this causes the notifier registry below to try and
5339 	 * give link-local addresses to all devices besides loopback_dev
5340 	 * first, then loopback_dev, which cases all the non-loopback_dev
5341 	 * devices to fail to get a link-local address.
5342 	 *
5343 	 * So, as a temporary fix, allocate the ipv6 structure for
5344 	 * loopback_dev first by hand.
5345 	 * Longer term, all of the dependencies ipv6 has upon the loopback
5346 	 * device and it being up should be removed.
5347 	 */
5348 	rtnl_lock();
5349 	if (!ipv6_add_dev(init_net.loopback_dev))
5350 		err = -ENOMEM;
5351 	rtnl_unlock();
5352 	if (err)
5353 		goto errlo;
5354 
5355 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5356 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
5357 
5358 	register_netdevice_notifier(&ipv6_dev_notf);
5359 
5360 	addrconf_verify();
5361 
5362 	rtnl_af_register(&inet6_ops);
5363 
5364 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
5365 			      NULL);
5366 	if (err < 0)
5367 		goto errout;
5368 
5369 	/* Only the first call to __rtnl_register can fail */
5370 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
5371 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
5372 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
5373 			inet6_dump_ifaddr, NULL);
5374 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
5375 			inet6_dump_ifmcaddr, NULL);
5376 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
5377 			inet6_dump_ifacaddr, NULL);
5378 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
5379 			inet6_netconf_dump_devconf, NULL);
5380 
5381 	ipv6_addr_label_rtnl_register();
5382 
5383 	return 0;
5384 errout:
5385 	rtnl_af_unregister(&inet6_ops);
5386 	unregister_netdevice_notifier(&ipv6_dev_notf);
5387 errlo:
5388 	destroy_workqueue(addrconf_wq);
5389 out_nowq:
5390 	unregister_pernet_subsys(&addrconf_ops);
5391 out_addrlabel:
5392 	ipv6_addr_label_cleanup();
5393 out:
5394 	return err;
5395 }
5396 
5397 void addrconf_cleanup(void)
5398 {
5399 	struct net_device *dev;
5400 	int i;
5401 
5402 	unregister_netdevice_notifier(&ipv6_dev_notf);
5403 	unregister_pernet_subsys(&addrconf_ops);
5404 	ipv6_addr_label_cleanup();
5405 
5406 	rtnl_lock();
5407 
5408 	__rtnl_af_unregister(&inet6_ops);
5409 
5410 	/* clean dev list */
5411 	for_each_netdev(&init_net, dev) {
5412 		if (__in6_dev_get(dev) == NULL)
5413 			continue;
5414 		addrconf_ifdown(dev, 1);
5415 	}
5416 	addrconf_ifdown(init_net.loopback_dev, 2);
5417 
5418 	/*
5419 	 *	Check hash table.
5420 	 */
5421 	spin_lock_bh(&addrconf_hash_lock);
5422 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
5423 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
5424 	spin_unlock_bh(&addrconf_hash_lock);
5425 	cancel_delayed_work(&addr_chk_work);
5426 	rtnl_unlock();
5427 
5428 	destroy_workqueue(addrconf_wq);
5429 }
5430