xref: /linux/net/ipv6/addrconf.c (revision 83a37b3292f4aca799b355179ad6fbdd78a08e10)
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/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
102 #else
103 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 #define IPV6_MAX_STRLEN \
109 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
110 
111 static inline u32 cstamp_delta(unsigned long cstamp)
112 {
113 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
114 }
115 
116 static inline s32 rfc3315_s14_backoff_init(s32 irt)
117 {
118 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
119 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
120 	do_div(tmp, 1000000);
121 	return (s32)tmp;
122 }
123 
124 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
125 {
126 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
127 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
128 	do_div(tmp, 1000000);
129 	if ((s32)tmp > mrt) {
130 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
131 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
132 		do_div(tmp, 1000000);
133 	}
134 	return (s32)tmp;
135 }
136 
137 #ifdef CONFIG_SYSCTL
138 static int addrconf_sysctl_register(struct inet6_dev *idev);
139 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
140 #else
141 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
142 {
143 	return 0;
144 }
145 
146 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
147 {
148 }
149 #endif
150 
151 static void ipv6_regen_rndid(struct inet6_dev *idev);
152 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
153 
154 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
155 static int ipv6_count_addresses(const struct inet6_dev *idev);
156 static int ipv6_generate_stable_address(struct in6_addr *addr,
157 					u8 dad_count,
158 					const struct inet6_dev *idev);
159 
160 /*
161  *	Configured unicast address hash table
162  */
163 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
164 static DEFINE_SPINLOCK(addrconf_hash_lock);
165 
166 static void addrconf_verify(void);
167 static void addrconf_verify_rtnl(void);
168 static void addrconf_verify_work(struct work_struct *);
169 
170 static struct workqueue_struct *addrconf_wq;
171 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
172 
173 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
174 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
175 
176 static void addrconf_type_change(struct net_device *dev,
177 				 unsigned long event);
178 static int addrconf_ifdown(struct net_device *dev, int how);
179 
180 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
181 						  int plen,
182 						  const struct net_device *dev,
183 						  u32 flags, u32 noflags);
184 
185 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
186 static void addrconf_dad_work(struct work_struct *w);
187 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id);
188 static void addrconf_dad_run(struct inet6_dev *idev);
189 static void addrconf_rs_timer(unsigned long data);
190 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
191 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
192 
193 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
194 				struct prefix_info *pinfo);
195 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
196 			       struct net_device *dev);
197 
198 static struct ipv6_devconf ipv6_devconf __read_mostly = {
199 	.forwarding		= 0,
200 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
201 	.mtu6			= IPV6_MIN_MTU,
202 	.accept_ra		= 1,
203 	.accept_redirects	= 1,
204 	.autoconf		= 1,
205 	.force_mld_version	= 0,
206 	.mldv1_unsolicited_report_interval = 10 * HZ,
207 	.mldv2_unsolicited_report_interval = HZ,
208 	.dad_transmits		= 1,
209 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
210 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
211 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
212 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
213 	.use_tempaddr		= 0,
214 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
215 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
216 	.regen_max_retry	= REGEN_MAX_RETRY,
217 	.max_desync_factor	= MAX_DESYNC_FACTOR,
218 	.max_addresses		= IPV6_MAX_ADDRESSES,
219 	.accept_ra_defrtr	= 1,
220 	.accept_ra_from_local	= 0,
221 	.accept_ra_min_hop_limit= 1,
222 	.accept_ra_pinfo	= 1,
223 #ifdef CONFIG_IPV6_ROUTER_PREF
224 	.accept_ra_rtr_pref	= 1,
225 	.rtr_probe_interval	= 60 * HZ,
226 #ifdef CONFIG_IPV6_ROUTE_INFO
227 	.accept_ra_rt_info_min_plen = 0,
228 	.accept_ra_rt_info_max_plen = 0,
229 #endif
230 #endif
231 	.proxy_ndp		= 0,
232 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
233 	.disable_ipv6		= 0,
234 	.accept_dad		= 1,
235 	.suppress_frag_ndisc	= 1,
236 	.accept_ra_mtu		= 1,
237 	.stable_secret		= {
238 		.initialized = false,
239 	},
240 	.use_oif_addrs_only	= 0,
241 	.ignore_routes_with_linkdown = 0,
242 	.keep_addr_on_down	= 0,
243 	.seg6_enabled		= 0,
244 #ifdef CONFIG_IPV6_SEG6_HMAC
245 	.seg6_require_hmac	= 0,
246 #endif
247 	.enhanced_dad           = 1,
248 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
249 	.disable_policy		= 0,
250 };
251 
252 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
253 	.forwarding		= 0,
254 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
255 	.mtu6			= IPV6_MIN_MTU,
256 	.accept_ra		= 1,
257 	.accept_redirects	= 1,
258 	.autoconf		= 1,
259 	.force_mld_version	= 0,
260 	.mldv1_unsolicited_report_interval = 10 * HZ,
261 	.mldv2_unsolicited_report_interval = HZ,
262 	.dad_transmits		= 1,
263 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
264 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
265 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
266 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
267 	.use_tempaddr		= 0,
268 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
269 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
270 	.regen_max_retry	= REGEN_MAX_RETRY,
271 	.max_desync_factor	= MAX_DESYNC_FACTOR,
272 	.max_addresses		= IPV6_MAX_ADDRESSES,
273 	.accept_ra_defrtr	= 1,
274 	.accept_ra_from_local	= 0,
275 	.accept_ra_min_hop_limit= 1,
276 	.accept_ra_pinfo	= 1,
277 #ifdef CONFIG_IPV6_ROUTER_PREF
278 	.accept_ra_rtr_pref	= 1,
279 	.rtr_probe_interval	= 60 * HZ,
280 #ifdef CONFIG_IPV6_ROUTE_INFO
281 	.accept_ra_rt_info_min_plen = 0,
282 	.accept_ra_rt_info_max_plen = 0,
283 #endif
284 #endif
285 	.proxy_ndp		= 0,
286 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
287 	.disable_ipv6		= 0,
288 	.accept_dad		= 1,
289 	.suppress_frag_ndisc	= 1,
290 	.accept_ra_mtu		= 1,
291 	.stable_secret		= {
292 		.initialized = false,
293 	},
294 	.use_oif_addrs_only	= 0,
295 	.ignore_routes_with_linkdown = 0,
296 	.keep_addr_on_down	= 0,
297 	.seg6_enabled		= 0,
298 #ifdef CONFIG_IPV6_SEG6_HMAC
299 	.seg6_require_hmac	= 0,
300 #endif
301 	.enhanced_dad           = 1,
302 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
303 	.disable_policy		= 0,
304 };
305 
306 /* Check if link is ready: is it up and is a valid qdisc available */
307 static inline bool addrconf_link_ready(const struct net_device *dev)
308 {
309 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
310 }
311 
312 static void addrconf_del_rs_timer(struct inet6_dev *idev)
313 {
314 	if (del_timer(&idev->rs_timer))
315 		__in6_dev_put(idev);
316 }
317 
318 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
319 {
320 	if (cancel_delayed_work(&ifp->dad_work))
321 		__in6_ifa_put(ifp);
322 }
323 
324 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
325 				  unsigned long when)
326 {
327 	if (!timer_pending(&idev->rs_timer))
328 		in6_dev_hold(idev);
329 	mod_timer(&idev->rs_timer, jiffies + when);
330 }
331 
332 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
333 				   unsigned long delay)
334 {
335 	in6_ifa_hold(ifp);
336 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
337 		in6_ifa_put(ifp);
338 }
339 
340 static int snmp6_alloc_dev(struct inet6_dev *idev)
341 {
342 	int i;
343 
344 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
345 	if (!idev->stats.ipv6)
346 		goto err_ip;
347 
348 	for_each_possible_cpu(i) {
349 		struct ipstats_mib *addrconf_stats;
350 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
351 		u64_stats_init(&addrconf_stats->syncp);
352 	}
353 
354 
355 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
356 					GFP_KERNEL);
357 	if (!idev->stats.icmpv6dev)
358 		goto err_icmp;
359 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
360 					   GFP_KERNEL);
361 	if (!idev->stats.icmpv6msgdev)
362 		goto err_icmpmsg;
363 
364 	return 0;
365 
366 err_icmpmsg:
367 	kfree(idev->stats.icmpv6dev);
368 err_icmp:
369 	free_percpu(idev->stats.ipv6);
370 err_ip:
371 	return -ENOMEM;
372 }
373 
374 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
375 {
376 	struct inet6_dev *ndev;
377 	int err = -ENOMEM;
378 
379 	ASSERT_RTNL();
380 
381 	if (dev->mtu < IPV6_MIN_MTU)
382 		return ERR_PTR(-EINVAL);
383 
384 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
385 	if (!ndev)
386 		return ERR_PTR(err);
387 
388 	rwlock_init(&ndev->lock);
389 	ndev->dev = dev;
390 	INIT_LIST_HEAD(&ndev->addr_list);
391 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
392 		    (unsigned long)ndev);
393 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
394 
395 	if (ndev->cnf.stable_secret.initialized)
396 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
397 	else
398 		ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
399 
400 	ndev->cnf.mtu6 = dev->mtu;
401 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
402 	if (!ndev->nd_parms) {
403 		kfree(ndev);
404 		return ERR_PTR(err);
405 	}
406 	if (ndev->cnf.forwarding)
407 		dev_disable_lro(dev);
408 	/* We refer to the device */
409 	dev_hold(dev);
410 
411 	if (snmp6_alloc_dev(ndev) < 0) {
412 		ADBG(KERN_WARNING
413 			"%s: cannot allocate memory for statistics; dev=%s.\n",
414 			__func__, dev->name);
415 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
416 		dev_put(dev);
417 		kfree(ndev);
418 		return ERR_PTR(err);
419 	}
420 
421 	if (snmp6_register_dev(ndev) < 0) {
422 		ADBG(KERN_WARNING
423 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
424 			__func__, dev->name);
425 		goto err_release;
426 	}
427 
428 	/* One reference from device. */
429 	refcount_set(&ndev->refcnt, 1);
430 
431 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
432 		ndev->cnf.accept_dad = -1;
433 
434 #if IS_ENABLED(CONFIG_IPV6_SIT)
435 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
436 		pr_info("%s: Disabled Multicast RS\n", dev->name);
437 		ndev->cnf.rtr_solicits = 0;
438 	}
439 #endif
440 
441 	INIT_LIST_HEAD(&ndev->tempaddr_list);
442 	ndev->desync_factor = U32_MAX;
443 	if ((dev->flags&IFF_LOOPBACK) ||
444 	    dev->type == ARPHRD_TUNNEL ||
445 	    dev->type == ARPHRD_TUNNEL6 ||
446 	    dev->type == ARPHRD_SIT ||
447 	    dev->type == ARPHRD_NONE) {
448 		ndev->cnf.use_tempaddr = -1;
449 	} else
450 		ipv6_regen_rndid(ndev);
451 
452 	ndev->token = in6addr_any;
453 
454 	if (netif_running(dev) && addrconf_link_ready(dev))
455 		ndev->if_flags |= IF_READY;
456 
457 	ipv6_mc_init_dev(ndev);
458 	ndev->tstamp = jiffies;
459 	err = addrconf_sysctl_register(ndev);
460 	if (err) {
461 		ipv6_mc_destroy_dev(ndev);
462 		snmp6_unregister_dev(ndev);
463 		goto err_release;
464 	}
465 	/* protected by rtnl_lock */
466 	rcu_assign_pointer(dev->ip6_ptr, ndev);
467 
468 	/* Join interface-local all-node multicast group */
469 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
470 
471 	/* Join all-node multicast group */
472 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
473 
474 	/* Join all-router multicast group if forwarding is set */
475 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
476 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
477 
478 	return ndev;
479 
480 err_release:
481 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
482 	ndev->dead = 1;
483 	in6_dev_finish_destroy(ndev);
484 	return ERR_PTR(err);
485 }
486 
487 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
488 {
489 	struct inet6_dev *idev;
490 
491 	ASSERT_RTNL();
492 
493 	idev = __in6_dev_get(dev);
494 	if (!idev) {
495 		idev = ipv6_add_dev(dev);
496 		if (IS_ERR(idev))
497 			return NULL;
498 	}
499 
500 	if (dev->flags&IFF_UP)
501 		ipv6_mc_up(idev);
502 	return idev;
503 }
504 
505 static int inet6_netconf_msgsize_devconf(int type)
506 {
507 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
508 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
509 	bool all = false;
510 
511 	if (type == NETCONFA_ALL)
512 		all = true;
513 
514 	if (all || type == NETCONFA_FORWARDING)
515 		size += nla_total_size(4);
516 #ifdef CONFIG_IPV6_MROUTE
517 	if (all || type == NETCONFA_MC_FORWARDING)
518 		size += nla_total_size(4);
519 #endif
520 	if (all || type == NETCONFA_PROXY_NEIGH)
521 		size += nla_total_size(4);
522 
523 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
524 		size += nla_total_size(4);
525 
526 	return size;
527 }
528 
529 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
530 				      struct ipv6_devconf *devconf, u32 portid,
531 				      u32 seq, int event, unsigned int flags,
532 				      int type)
533 {
534 	struct nlmsghdr  *nlh;
535 	struct netconfmsg *ncm;
536 	bool all = false;
537 
538 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
539 			flags);
540 	if (!nlh)
541 		return -EMSGSIZE;
542 
543 	if (type == NETCONFA_ALL)
544 		all = true;
545 
546 	ncm = nlmsg_data(nlh);
547 	ncm->ncm_family = AF_INET6;
548 
549 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
550 		goto nla_put_failure;
551 
552 	if (!devconf)
553 		goto out;
554 
555 	if ((all || type == NETCONFA_FORWARDING) &&
556 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
557 		goto nla_put_failure;
558 #ifdef CONFIG_IPV6_MROUTE
559 	if ((all || type == NETCONFA_MC_FORWARDING) &&
560 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
561 			devconf->mc_forwarding) < 0)
562 		goto nla_put_failure;
563 #endif
564 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
565 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
566 		goto nla_put_failure;
567 
568 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
569 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
570 			devconf->ignore_routes_with_linkdown) < 0)
571 		goto nla_put_failure;
572 
573 out:
574 	nlmsg_end(skb, nlh);
575 	return 0;
576 
577 nla_put_failure:
578 	nlmsg_cancel(skb, nlh);
579 	return -EMSGSIZE;
580 }
581 
582 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
583 				  int ifindex, struct ipv6_devconf *devconf)
584 {
585 	struct sk_buff *skb;
586 	int err = -ENOBUFS;
587 
588 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
589 	if (!skb)
590 		goto errout;
591 
592 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
593 					 event, 0, type);
594 	if (err < 0) {
595 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
596 		WARN_ON(err == -EMSGSIZE);
597 		kfree_skb(skb);
598 		goto errout;
599 	}
600 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
601 	return;
602 errout:
603 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
604 }
605 
606 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
607 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
608 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
609 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
610 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
611 };
612 
613 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
614 				     struct nlmsghdr *nlh,
615 				     struct netlink_ext_ack *extack)
616 {
617 	struct net *net = sock_net(in_skb->sk);
618 	struct nlattr *tb[NETCONFA_MAX+1];
619 	struct inet6_dev *in6_dev = NULL;
620 	struct net_device *dev = NULL;
621 	struct netconfmsg *ncm;
622 	struct sk_buff *skb;
623 	struct ipv6_devconf *devconf;
624 	int ifindex;
625 	int err;
626 
627 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
628 			  devconf_ipv6_policy, extack);
629 	if (err < 0)
630 		return err;
631 
632 	if (!tb[NETCONFA_IFINDEX])
633 		return -EINVAL;
634 
635 	err = -EINVAL;
636 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
637 	switch (ifindex) {
638 	case NETCONFA_IFINDEX_ALL:
639 		devconf = net->ipv6.devconf_all;
640 		break;
641 	case NETCONFA_IFINDEX_DEFAULT:
642 		devconf = net->ipv6.devconf_dflt;
643 		break;
644 	default:
645 		dev = dev_get_by_index(net, ifindex);
646 		if (!dev)
647 			return -EINVAL;
648 		in6_dev = in6_dev_get(dev);
649 		if (!in6_dev)
650 			goto errout;
651 		devconf = &in6_dev->cnf;
652 		break;
653 	}
654 
655 	err = -ENOBUFS;
656 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
657 	if (!skb)
658 		goto errout;
659 
660 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
661 					 NETLINK_CB(in_skb).portid,
662 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
663 					 NETCONFA_ALL);
664 	if (err < 0) {
665 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
666 		WARN_ON(err == -EMSGSIZE);
667 		kfree_skb(skb);
668 		goto errout;
669 	}
670 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
671 errout:
672 	if (in6_dev)
673 		in6_dev_put(in6_dev);
674 	if (dev)
675 		dev_put(dev);
676 	return err;
677 }
678 
679 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
680 				      struct netlink_callback *cb)
681 {
682 	struct net *net = sock_net(skb->sk);
683 	int h, s_h;
684 	int idx, s_idx;
685 	struct net_device *dev;
686 	struct inet6_dev *idev;
687 	struct hlist_head *head;
688 
689 	s_h = cb->args[0];
690 	s_idx = idx = cb->args[1];
691 
692 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
693 		idx = 0;
694 		head = &net->dev_index_head[h];
695 		rcu_read_lock();
696 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
697 			  net->dev_base_seq;
698 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
699 			if (idx < s_idx)
700 				goto cont;
701 			idev = __in6_dev_get(dev);
702 			if (!idev)
703 				goto cont;
704 
705 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
706 						       &idev->cnf,
707 						       NETLINK_CB(cb->skb).portid,
708 						       cb->nlh->nlmsg_seq,
709 						       RTM_NEWNETCONF,
710 						       NLM_F_MULTI,
711 						       NETCONFA_ALL) < 0) {
712 				rcu_read_unlock();
713 				goto done;
714 			}
715 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
716 cont:
717 			idx++;
718 		}
719 		rcu_read_unlock();
720 	}
721 	if (h == NETDEV_HASHENTRIES) {
722 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
723 					       net->ipv6.devconf_all,
724 					       NETLINK_CB(cb->skb).portid,
725 					       cb->nlh->nlmsg_seq,
726 					       RTM_NEWNETCONF, NLM_F_MULTI,
727 					       NETCONFA_ALL) < 0)
728 			goto done;
729 		else
730 			h++;
731 	}
732 	if (h == NETDEV_HASHENTRIES + 1) {
733 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
734 					       net->ipv6.devconf_dflt,
735 					       NETLINK_CB(cb->skb).portid,
736 					       cb->nlh->nlmsg_seq,
737 					       RTM_NEWNETCONF, NLM_F_MULTI,
738 					       NETCONFA_ALL) < 0)
739 			goto done;
740 		else
741 			h++;
742 	}
743 done:
744 	cb->args[0] = h;
745 	cb->args[1] = idx;
746 
747 	return skb->len;
748 }
749 
750 #ifdef CONFIG_SYSCTL
751 static void dev_forward_change(struct inet6_dev *idev)
752 {
753 	struct net_device *dev;
754 	struct inet6_ifaddr *ifa;
755 
756 	if (!idev)
757 		return;
758 	dev = idev->dev;
759 	if (idev->cnf.forwarding)
760 		dev_disable_lro(dev);
761 	if (dev->flags & IFF_MULTICAST) {
762 		if (idev->cnf.forwarding) {
763 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
764 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
765 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
766 		} else {
767 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
768 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
769 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
770 		}
771 	}
772 
773 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
774 		if (ifa->flags&IFA_F_TENTATIVE)
775 			continue;
776 		if (idev->cnf.forwarding)
777 			addrconf_join_anycast(ifa);
778 		else
779 			addrconf_leave_anycast(ifa);
780 	}
781 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
782 				     NETCONFA_FORWARDING,
783 				     dev->ifindex, &idev->cnf);
784 }
785 
786 
787 static void addrconf_forward_change(struct net *net, __s32 newf)
788 {
789 	struct net_device *dev;
790 	struct inet6_dev *idev;
791 
792 	for_each_netdev(net, dev) {
793 		idev = __in6_dev_get(dev);
794 		if (idev) {
795 			int changed = (!idev->cnf.forwarding) ^ (!newf);
796 			idev->cnf.forwarding = newf;
797 			if (changed)
798 				dev_forward_change(idev);
799 		}
800 	}
801 }
802 
803 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
804 {
805 	struct net *net;
806 	int old;
807 
808 	if (!rtnl_trylock())
809 		return restart_syscall();
810 
811 	net = (struct net *)table->extra2;
812 	old = *p;
813 	*p = newf;
814 
815 	if (p == &net->ipv6.devconf_dflt->forwarding) {
816 		if ((!newf) ^ (!old))
817 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
818 						     NETCONFA_FORWARDING,
819 						     NETCONFA_IFINDEX_DEFAULT,
820 						     net->ipv6.devconf_dflt);
821 		rtnl_unlock();
822 		return 0;
823 	}
824 
825 	if (p == &net->ipv6.devconf_all->forwarding) {
826 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
827 
828 		net->ipv6.devconf_dflt->forwarding = newf;
829 		if ((!newf) ^ (!old_dflt))
830 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
831 						     NETCONFA_FORWARDING,
832 						     NETCONFA_IFINDEX_DEFAULT,
833 						     net->ipv6.devconf_dflt);
834 
835 		addrconf_forward_change(net, newf);
836 		if ((!newf) ^ (!old))
837 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
838 						     NETCONFA_FORWARDING,
839 						     NETCONFA_IFINDEX_ALL,
840 						     net->ipv6.devconf_all);
841 	} else if ((!newf) ^ (!old))
842 		dev_forward_change((struct inet6_dev *)table->extra1);
843 	rtnl_unlock();
844 
845 	if (newf)
846 		rt6_purge_dflt_routers(net);
847 	return 1;
848 }
849 
850 static void addrconf_linkdown_change(struct net *net, __s32 newf)
851 {
852 	struct net_device *dev;
853 	struct inet6_dev *idev;
854 
855 	for_each_netdev(net, dev) {
856 		idev = __in6_dev_get(dev);
857 		if (idev) {
858 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
859 
860 			idev->cnf.ignore_routes_with_linkdown = newf;
861 			if (changed)
862 				inet6_netconf_notify_devconf(dev_net(dev),
863 							     RTM_NEWNETCONF,
864 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
865 							     dev->ifindex,
866 							     &idev->cnf);
867 		}
868 	}
869 }
870 
871 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
872 {
873 	struct net *net;
874 	int old;
875 
876 	if (!rtnl_trylock())
877 		return restart_syscall();
878 
879 	net = (struct net *)table->extra2;
880 	old = *p;
881 	*p = newf;
882 
883 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
884 		if ((!newf) ^ (!old))
885 			inet6_netconf_notify_devconf(net,
886 						     RTM_NEWNETCONF,
887 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
888 						     NETCONFA_IFINDEX_DEFAULT,
889 						     net->ipv6.devconf_dflt);
890 		rtnl_unlock();
891 		return 0;
892 	}
893 
894 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
895 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
896 		addrconf_linkdown_change(net, newf);
897 		if ((!newf) ^ (!old))
898 			inet6_netconf_notify_devconf(net,
899 						     RTM_NEWNETCONF,
900 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
901 						     NETCONFA_IFINDEX_ALL,
902 						     net->ipv6.devconf_all);
903 	}
904 	rtnl_unlock();
905 
906 	return 1;
907 }
908 
909 #endif
910 
911 /* Nobody refers to this ifaddr, destroy it */
912 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
913 {
914 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
915 
916 #ifdef NET_REFCNT_DEBUG
917 	pr_debug("%s\n", __func__);
918 #endif
919 
920 	in6_dev_put(ifp->idev);
921 
922 	if (cancel_delayed_work(&ifp->dad_work))
923 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
924 			  ifp);
925 
926 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
927 		pr_warn("Freeing alive inet6 address %p\n", ifp);
928 		return;
929 	}
930 	ip6_rt_put(ifp->rt);
931 
932 	kfree_rcu(ifp, rcu);
933 }
934 
935 static void
936 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
937 {
938 	struct list_head *p;
939 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
940 
941 	/*
942 	 * Each device address list is sorted in order of scope -
943 	 * global before linklocal.
944 	 */
945 	list_for_each(p, &idev->addr_list) {
946 		struct inet6_ifaddr *ifa
947 			= list_entry(p, struct inet6_ifaddr, if_list);
948 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
949 			break;
950 	}
951 
952 	list_add_tail_rcu(&ifp->if_list, p);
953 }
954 
955 static u32 inet6_addr_hash(const struct in6_addr *addr)
956 {
957 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
958 }
959 
960 /* On success it returns ifp with increased reference count */
961 
962 static struct inet6_ifaddr *
963 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
964 	      const struct in6_addr *peer_addr, int pfxlen,
965 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
966 {
967 	struct net *net = dev_net(idev->dev);
968 	struct inet6_ifaddr *ifa = NULL;
969 	struct rt6_info *rt;
970 	struct in6_validator_info i6vi;
971 	unsigned int hash;
972 	int err = 0;
973 	int addr_type = ipv6_addr_type(addr);
974 
975 	if (addr_type == IPV6_ADDR_ANY ||
976 	    addr_type & IPV6_ADDR_MULTICAST ||
977 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
978 	     addr_type & IPV6_ADDR_LOOPBACK))
979 		return ERR_PTR(-EADDRNOTAVAIL);
980 
981 	rcu_read_lock_bh();
982 
983 	in6_dev_hold(idev);
984 
985 	if (idev->dead) {
986 		err = -ENODEV;			/*XXX*/
987 		goto out2;
988 	}
989 
990 	if (idev->cnf.disable_ipv6) {
991 		err = -EACCES;
992 		goto out2;
993 	}
994 
995 	i6vi.i6vi_addr = *addr;
996 	i6vi.i6vi_dev = idev;
997 	rcu_read_unlock_bh();
998 
999 	err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1000 
1001 	rcu_read_lock_bh();
1002 	err = notifier_to_errno(err);
1003 	if (err)
1004 		goto out2;
1005 
1006 	spin_lock(&addrconf_hash_lock);
1007 
1008 	/* Ignore adding duplicate addresses on an interface */
1009 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
1010 		ADBG("ipv6_add_addr: already assigned\n");
1011 		err = -EEXIST;
1012 		goto out;
1013 	}
1014 
1015 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
1016 
1017 	if (!ifa) {
1018 		ADBG("ipv6_add_addr: malloc failed\n");
1019 		err = -ENOBUFS;
1020 		goto out;
1021 	}
1022 
1023 	rt = addrconf_dst_alloc(idev, addr, false);
1024 	if (IS_ERR(rt)) {
1025 		err = PTR_ERR(rt);
1026 		goto out;
1027 	}
1028 
1029 	if (net->ipv6.devconf_all->disable_policy ||
1030 	    idev->cnf.disable_policy)
1031 		rt->dst.flags |= DST_NOPOLICY;
1032 
1033 	neigh_parms_data_state_setall(idev->nd_parms);
1034 
1035 	ifa->addr = *addr;
1036 	if (peer_addr)
1037 		ifa->peer_addr = *peer_addr;
1038 
1039 	spin_lock_init(&ifa->lock);
1040 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1041 	INIT_HLIST_NODE(&ifa->addr_lst);
1042 	ifa->scope = scope;
1043 	ifa->prefix_len = pfxlen;
1044 	ifa->flags = flags;
1045 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1046 	if (!(flags & IFA_F_NODAD))
1047 		ifa->flags |= IFA_F_TENTATIVE;
1048 	ifa->valid_lft = valid_lft;
1049 	ifa->prefered_lft = prefered_lft;
1050 	ifa->cstamp = ifa->tstamp = jiffies;
1051 	ifa->tokenized = false;
1052 
1053 	ifa->rt = rt;
1054 
1055 	ifa->idev = idev;
1056 	/* For caller */
1057 	refcount_set(&ifa->refcnt, 1);
1058 
1059 	/* Add to big hash table */
1060 	hash = inet6_addr_hash(addr);
1061 
1062 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1063 	spin_unlock(&addrconf_hash_lock);
1064 
1065 	write_lock(&idev->lock);
1066 	/* Add to inet6_dev unicast addr list. */
1067 	ipv6_link_dev_addr(idev, ifa);
1068 
1069 	if (ifa->flags&IFA_F_TEMPORARY) {
1070 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1071 		in6_ifa_hold(ifa);
1072 	}
1073 
1074 	in6_ifa_hold(ifa);
1075 	write_unlock(&idev->lock);
1076 out2:
1077 	rcu_read_unlock_bh();
1078 
1079 	if (likely(err == 0))
1080 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1081 	else {
1082 		kfree(ifa);
1083 		in6_dev_put(idev);
1084 		ifa = ERR_PTR(err);
1085 	}
1086 
1087 	return ifa;
1088 out:
1089 	spin_unlock(&addrconf_hash_lock);
1090 	goto out2;
1091 }
1092 
1093 enum cleanup_prefix_rt_t {
1094 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1095 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1096 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1097 };
1098 
1099 /*
1100  * Check, whether the prefix for ifp would still need a prefix route
1101  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1102  * constants.
1103  *
1104  * 1) we don't purge prefix if address was not permanent.
1105  *    prefix is managed by its own lifetime.
1106  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1107  * 3) if there are no addresses, delete prefix.
1108  * 4) if there are still other permanent address(es),
1109  *    corresponding prefix is still permanent.
1110  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1111  *    don't purge the prefix, assume user space is managing it.
1112  * 6) otherwise, update prefix lifetime to the
1113  *    longest valid lifetime among the corresponding
1114  *    addresses on the device.
1115  *    Note: subsequent RA will update lifetime.
1116  **/
1117 static enum cleanup_prefix_rt_t
1118 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1119 {
1120 	struct inet6_ifaddr *ifa;
1121 	struct inet6_dev *idev = ifp->idev;
1122 	unsigned long lifetime;
1123 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1124 
1125 	*expires = jiffies;
1126 
1127 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1128 		if (ifa == ifp)
1129 			continue;
1130 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1131 				       ifp->prefix_len))
1132 			continue;
1133 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1134 			return CLEANUP_PREFIX_RT_NOP;
1135 
1136 		action = CLEANUP_PREFIX_RT_EXPIRE;
1137 
1138 		spin_lock(&ifa->lock);
1139 
1140 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1141 		/*
1142 		 * Note: Because this address is
1143 		 * not permanent, lifetime <
1144 		 * LONG_MAX / HZ here.
1145 		 */
1146 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1147 			*expires = ifa->tstamp + lifetime * HZ;
1148 		spin_unlock(&ifa->lock);
1149 	}
1150 
1151 	return action;
1152 }
1153 
1154 static void
1155 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1156 {
1157 	struct rt6_info *rt;
1158 
1159 	rt = addrconf_get_prefix_route(&ifp->addr,
1160 				       ifp->prefix_len,
1161 				       ifp->idev->dev,
1162 				       0, RTF_GATEWAY | RTF_DEFAULT);
1163 	if (rt) {
1164 		if (del_rt)
1165 			ip6_del_rt(rt);
1166 		else {
1167 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1168 				rt6_set_expires(rt, expires);
1169 			ip6_rt_put(rt);
1170 		}
1171 	}
1172 }
1173 
1174 
1175 /* This function wants to get referenced ifp and releases it before return */
1176 
1177 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1178 {
1179 	int state;
1180 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1181 	unsigned long expires;
1182 
1183 	ASSERT_RTNL();
1184 
1185 	spin_lock_bh(&ifp->lock);
1186 	state = ifp->state;
1187 	ifp->state = INET6_IFADDR_STATE_DEAD;
1188 	spin_unlock_bh(&ifp->lock);
1189 
1190 	if (state == INET6_IFADDR_STATE_DEAD)
1191 		goto out;
1192 
1193 	spin_lock_bh(&addrconf_hash_lock);
1194 	hlist_del_init_rcu(&ifp->addr_lst);
1195 	spin_unlock_bh(&addrconf_hash_lock);
1196 
1197 	write_lock_bh(&ifp->idev->lock);
1198 
1199 	if (ifp->flags&IFA_F_TEMPORARY) {
1200 		list_del(&ifp->tmp_list);
1201 		if (ifp->ifpub) {
1202 			in6_ifa_put(ifp->ifpub);
1203 			ifp->ifpub = NULL;
1204 		}
1205 		__in6_ifa_put(ifp);
1206 	}
1207 
1208 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1209 		action = check_cleanup_prefix_route(ifp, &expires);
1210 
1211 	list_del_rcu(&ifp->if_list);
1212 	__in6_ifa_put(ifp);
1213 
1214 	write_unlock_bh(&ifp->idev->lock);
1215 
1216 	addrconf_del_dad_work(ifp);
1217 
1218 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1219 
1220 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1221 
1222 	if (action != CLEANUP_PREFIX_RT_NOP) {
1223 		cleanup_prefix_route(ifp, expires,
1224 			action == CLEANUP_PREFIX_RT_DEL);
1225 	}
1226 
1227 	/* clean up prefsrc entries */
1228 	rt6_remove_prefsrc(ifp);
1229 out:
1230 	in6_ifa_put(ifp);
1231 }
1232 
1233 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1234 {
1235 	struct inet6_dev *idev = ifp->idev;
1236 	struct in6_addr addr, *tmpaddr;
1237 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1238 	unsigned long regen_advance;
1239 	int tmp_plen;
1240 	int ret = 0;
1241 	u32 addr_flags;
1242 	unsigned long now = jiffies;
1243 	long max_desync_factor;
1244 	s32 cnf_temp_preferred_lft;
1245 
1246 	write_lock_bh(&idev->lock);
1247 	if (ift) {
1248 		spin_lock_bh(&ift->lock);
1249 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1250 		spin_unlock_bh(&ift->lock);
1251 		tmpaddr = &addr;
1252 	} else {
1253 		tmpaddr = NULL;
1254 	}
1255 retry:
1256 	in6_dev_hold(idev);
1257 	if (idev->cnf.use_tempaddr <= 0) {
1258 		write_unlock_bh(&idev->lock);
1259 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1260 		in6_dev_put(idev);
1261 		ret = -1;
1262 		goto out;
1263 	}
1264 	spin_lock_bh(&ifp->lock);
1265 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1266 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1267 		spin_unlock_bh(&ifp->lock);
1268 		write_unlock_bh(&idev->lock);
1269 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1270 			__func__);
1271 		in6_dev_put(idev);
1272 		ret = -1;
1273 		goto out;
1274 	}
1275 	in6_ifa_hold(ifp);
1276 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1277 	ipv6_try_regen_rndid(idev, tmpaddr);
1278 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1279 	age = (now - ifp->tstamp) / HZ;
1280 
1281 	regen_advance = idev->cnf.regen_max_retry *
1282 			idev->cnf.dad_transmits *
1283 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1284 
1285 	/* recalculate max_desync_factor each time and update
1286 	 * idev->desync_factor if it's larger
1287 	 */
1288 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1289 	max_desync_factor = min_t(__u32,
1290 				  idev->cnf.max_desync_factor,
1291 				  cnf_temp_preferred_lft - regen_advance);
1292 
1293 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1294 		if (max_desync_factor > 0) {
1295 			get_random_bytes(&idev->desync_factor,
1296 					 sizeof(idev->desync_factor));
1297 			idev->desync_factor %= max_desync_factor;
1298 		} else {
1299 			idev->desync_factor = 0;
1300 		}
1301 	}
1302 
1303 	tmp_valid_lft = min_t(__u32,
1304 			      ifp->valid_lft,
1305 			      idev->cnf.temp_valid_lft + age);
1306 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1307 			    idev->desync_factor;
1308 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1309 	tmp_plen = ifp->prefix_len;
1310 	tmp_tstamp = ifp->tstamp;
1311 	spin_unlock_bh(&ifp->lock);
1312 
1313 	write_unlock_bh(&idev->lock);
1314 
1315 	/* A temporary address is created only if this calculated Preferred
1316 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1317 	 * an implementation must not create a temporary address with a zero
1318 	 * Preferred Lifetime.
1319 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1320 	 * temporary addresses being generated.
1321 	 */
1322 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1323 	if (tmp_prefered_lft <= regen_advance + age) {
1324 		in6_ifa_put(ifp);
1325 		in6_dev_put(idev);
1326 		ret = -1;
1327 		goto out;
1328 	}
1329 
1330 	addr_flags = IFA_F_TEMPORARY;
1331 	/* set in addrconf_prefix_rcv() */
1332 	if (ifp->flags & IFA_F_OPTIMISTIC)
1333 		addr_flags |= IFA_F_OPTIMISTIC;
1334 
1335 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1336 			    ipv6_addr_scope(&addr), addr_flags,
1337 			    tmp_valid_lft, tmp_prefered_lft);
1338 	if (IS_ERR(ift)) {
1339 		in6_ifa_put(ifp);
1340 		in6_dev_put(idev);
1341 		pr_info("%s: retry temporary address regeneration\n", __func__);
1342 		tmpaddr = &addr;
1343 		write_lock_bh(&idev->lock);
1344 		goto retry;
1345 	}
1346 
1347 	spin_lock_bh(&ift->lock);
1348 	ift->ifpub = ifp;
1349 	ift->cstamp = now;
1350 	ift->tstamp = tmp_tstamp;
1351 	spin_unlock_bh(&ift->lock);
1352 
1353 	addrconf_dad_start(ift);
1354 	in6_ifa_put(ift);
1355 	in6_dev_put(idev);
1356 out:
1357 	return ret;
1358 }
1359 
1360 /*
1361  *	Choose an appropriate source address (RFC3484)
1362  */
1363 enum {
1364 	IPV6_SADDR_RULE_INIT = 0,
1365 	IPV6_SADDR_RULE_LOCAL,
1366 	IPV6_SADDR_RULE_SCOPE,
1367 	IPV6_SADDR_RULE_PREFERRED,
1368 #ifdef CONFIG_IPV6_MIP6
1369 	IPV6_SADDR_RULE_HOA,
1370 #endif
1371 	IPV6_SADDR_RULE_OIF,
1372 	IPV6_SADDR_RULE_LABEL,
1373 	IPV6_SADDR_RULE_PRIVACY,
1374 	IPV6_SADDR_RULE_ORCHID,
1375 	IPV6_SADDR_RULE_PREFIX,
1376 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1377 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1378 #endif
1379 	IPV6_SADDR_RULE_MAX
1380 };
1381 
1382 struct ipv6_saddr_score {
1383 	int			rule;
1384 	int			addr_type;
1385 	struct inet6_ifaddr	*ifa;
1386 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1387 	int			scopedist;
1388 	int			matchlen;
1389 };
1390 
1391 struct ipv6_saddr_dst {
1392 	const struct in6_addr *addr;
1393 	int ifindex;
1394 	int scope;
1395 	int label;
1396 	unsigned int prefs;
1397 };
1398 
1399 static inline int ipv6_saddr_preferred(int type)
1400 {
1401 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1402 		return 1;
1403 	return 0;
1404 }
1405 
1406 static bool ipv6_use_optimistic_addr(struct net *net,
1407 				     struct inet6_dev *idev)
1408 {
1409 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1410 	if (!idev)
1411 		return false;
1412 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1413 		return false;
1414 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1415 		return false;
1416 
1417 	return true;
1418 #else
1419 	return false;
1420 #endif
1421 }
1422 
1423 static int ipv6_get_saddr_eval(struct net *net,
1424 			       struct ipv6_saddr_score *score,
1425 			       struct ipv6_saddr_dst *dst,
1426 			       int i)
1427 {
1428 	int ret;
1429 
1430 	if (i <= score->rule) {
1431 		switch (i) {
1432 		case IPV6_SADDR_RULE_SCOPE:
1433 			ret = score->scopedist;
1434 			break;
1435 		case IPV6_SADDR_RULE_PREFIX:
1436 			ret = score->matchlen;
1437 			break;
1438 		default:
1439 			ret = !!test_bit(i, score->scorebits);
1440 		}
1441 		goto out;
1442 	}
1443 
1444 	switch (i) {
1445 	case IPV6_SADDR_RULE_INIT:
1446 		/* Rule 0: remember if hiscore is not ready yet */
1447 		ret = !!score->ifa;
1448 		break;
1449 	case IPV6_SADDR_RULE_LOCAL:
1450 		/* Rule 1: Prefer same address */
1451 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1452 		break;
1453 	case IPV6_SADDR_RULE_SCOPE:
1454 		/* Rule 2: Prefer appropriate scope
1455 		 *
1456 		 *      ret
1457 		 *       ^
1458 		 *    -1 |  d 15
1459 		 *    ---+--+-+---> scope
1460 		 *       |
1461 		 *       |             d is scope of the destination.
1462 		 *  B-d  |  \
1463 		 *       |   \      <- smaller scope is better if
1464 		 *  B-15 |    \        if scope is enough for destination.
1465 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1466 		 * d-C-1 | /
1467 		 *       |/         <- greater is better
1468 		 *   -C  /             if scope is not enough for destination.
1469 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1470 		 *
1471 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1472 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1473 		 * Assume B = 0 and we get C > 29.
1474 		 */
1475 		ret = __ipv6_addr_src_scope(score->addr_type);
1476 		if (ret >= dst->scope)
1477 			ret = -ret;
1478 		else
1479 			ret -= 128;	/* 30 is enough */
1480 		score->scopedist = ret;
1481 		break;
1482 	case IPV6_SADDR_RULE_PREFERRED:
1483 	    {
1484 		/* Rule 3: Avoid deprecated and optimistic addresses */
1485 		u8 avoid = IFA_F_DEPRECATED;
1486 
1487 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1488 			avoid |= IFA_F_OPTIMISTIC;
1489 		ret = ipv6_saddr_preferred(score->addr_type) ||
1490 		      !(score->ifa->flags & avoid);
1491 		break;
1492 	    }
1493 #ifdef CONFIG_IPV6_MIP6
1494 	case IPV6_SADDR_RULE_HOA:
1495 	    {
1496 		/* Rule 4: Prefer home address */
1497 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1498 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1499 		break;
1500 	    }
1501 #endif
1502 	case IPV6_SADDR_RULE_OIF:
1503 		/* Rule 5: Prefer outgoing interface */
1504 		ret = (!dst->ifindex ||
1505 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1506 		break;
1507 	case IPV6_SADDR_RULE_LABEL:
1508 		/* Rule 6: Prefer matching label */
1509 		ret = ipv6_addr_label(net,
1510 				      &score->ifa->addr, score->addr_type,
1511 				      score->ifa->idev->dev->ifindex) == dst->label;
1512 		break;
1513 	case IPV6_SADDR_RULE_PRIVACY:
1514 	    {
1515 		/* Rule 7: Prefer public address
1516 		 * Note: prefer temporary address if use_tempaddr >= 2
1517 		 */
1518 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1519 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1520 				score->ifa->idev->cnf.use_tempaddr >= 2;
1521 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1522 		break;
1523 	    }
1524 	case IPV6_SADDR_RULE_ORCHID:
1525 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1526 		 *	    non-ORCHID vs non-ORCHID
1527 		 */
1528 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1529 			ipv6_addr_orchid(dst->addr));
1530 		break;
1531 	case IPV6_SADDR_RULE_PREFIX:
1532 		/* Rule 8: Use longest matching prefix */
1533 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1534 		if (ret > score->ifa->prefix_len)
1535 			ret = score->ifa->prefix_len;
1536 		score->matchlen = ret;
1537 		break;
1538 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1539 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1540 		/* Optimistic addresses still have lower precedence than other
1541 		 * preferred addresses.
1542 		 */
1543 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1544 		break;
1545 #endif
1546 	default:
1547 		ret = 0;
1548 	}
1549 
1550 	if (ret)
1551 		__set_bit(i, score->scorebits);
1552 	score->rule = i;
1553 out:
1554 	return ret;
1555 }
1556 
1557 static int __ipv6_dev_get_saddr(struct net *net,
1558 				struct ipv6_saddr_dst *dst,
1559 				struct inet6_dev *idev,
1560 				struct ipv6_saddr_score *scores,
1561 				int hiscore_idx)
1562 {
1563 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1564 
1565 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1566 		int i;
1567 
1568 		/*
1569 		 * - Tentative Address (RFC2462 section 5.4)
1570 		 *  - A tentative address is not considered
1571 		 *    "assigned to an interface" in the traditional
1572 		 *    sense, unless it is also flagged as optimistic.
1573 		 * - Candidate Source Address (section 4)
1574 		 *  - In any case, anycast addresses, multicast
1575 		 *    addresses, and the unspecified address MUST
1576 		 *    NOT be included in a candidate set.
1577 		 */
1578 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1579 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1580 			continue;
1581 
1582 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1583 
1584 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1585 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1586 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1587 					    idev->dev->name);
1588 			continue;
1589 		}
1590 
1591 		score->rule = -1;
1592 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1593 
1594 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1595 			int minihiscore, miniscore;
1596 
1597 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1598 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1599 
1600 			if (minihiscore > miniscore) {
1601 				if (i == IPV6_SADDR_RULE_SCOPE &&
1602 				    score->scopedist > 0) {
1603 					/*
1604 					 * special case:
1605 					 * each remaining entry
1606 					 * has too small (not enough)
1607 					 * scope, because ifa entries
1608 					 * are sorted by their scope
1609 					 * values.
1610 					 */
1611 					goto out;
1612 				}
1613 				break;
1614 			} else if (minihiscore < miniscore) {
1615 				swap(hiscore, score);
1616 				hiscore_idx = 1 - hiscore_idx;
1617 
1618 				/* restore our iterator */
1619 				score->ifa = hiscore->ifa;
1620 
1621 				break;
1622 			}
1623 		}
1624 	}
1625 out:
1626 	return hiscore_idx;
1627 }
1628 
1629 static int ipv6_get_saddr_master(struct net *net,
1630 				 const struct net_device *dst_dev,
1631 				 const struct net_device *master,
1632 				 struct ipv6_saddr_dst *dst,
1633 				 struct ipv6_saddr_score *scores,
1634 				 int hiscore_idx)
1635 {
1636 	struct inet6_dev *idev;
1637 
1638 	idev = __in6_dev_get(dst_dev);
1639 	if (idev)
1640 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1641 						   scores, hiscore_idx);
1642 
1643 	idev = __in6_dev_get(master);
1644 	if (idev)
1645 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1646 						   scores, hiscore_idx);
1647 
1648 	return hiscore_idx;
1649 }
1650 
1651 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1652 		       const struct in6_addr *daddr, unsigned int prefs,
1653 		       struct in6_addr *saddr)
1654 {
1655 	struct ipv6_saddr_score scores[2], *hiscore;
1656 	struct ipv6_saddr_dst dst;
1657 	struct inet6_dev *idev;
1658 	struct net_device *dev;
1659 	int dst_type;
1660 	bool use_oif_addr = false;
1661 	int hiscore_idx = 0;
1662 	int ret = 0;
1663 
1664 	dst_type = __ipv6_addr_type(daddr);
1665 	dst.addr = daddr;
1666 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1667 	dst.scope = __ipv6_addr_src_scope(dst_type);
1668 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1669 	dst.prefs = prefs;
1670 
1671 	scores[hiscore_idx].rule = -1;
1672 	scores[hiscore_idx].ifa = NULL;
1673 
1674 	rcu_read_lock();
1675 
1676 	/* Candidate Source Address (section 4)
1677 	 *  - multicast and link-local destination address,
1678 	 *    the set of candidate source address MUST only
1679 	 *    include addresses assigned to interfaces
1680 	 *    belonging to the same link as the outgoing
1681 	 *    interface.
1682 	 * (- For site-local destination addresses, the
1683 	 *    set of candidate source addresses MUST only
1684 	 *    include addresses assigned to interfaces
1685 	 *    belonging to the same site as the outgoing
1686 	 *    interface.)
1687 	 *  - "It is RECOMMENDED that the candidate source addresses
1688 	 *    be the set of unicast addresses assigned to the
1689 	 *    interface that will be used to send to the destination
1690 	 *    (the 'outgoing' interface)." (RFC 6724)
1691 	 */
1692 	if (dst_dev) {
1693 		idev = __in6_dev_get(dst_dev);
1694 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1695 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1696 		    (idev && idev->cnf.use_oif_addrs_only)) {
1697 			use_oif_addr = true;
1698 		}
1699 	}
1700 
1701 	if (use_oif_addr) {
1702 		if (idev)
1703 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1704 	} else {
1705 		const struct net_device *master;
1706 		int master_idx = 0;
1707 
1708 		/* if dst_dev exists and is enslaved to an L3 device, then
1709 		 * prefer addresses from dst_dev and then the master over
1710 		 * any other enslaved devices in the L3 domain.
1711 		 */
1712 		master = l3mdev_master_dev_rcu(dst_dev);
1713 		if (master) {
1714 			master_idx = master->ifindex;
1715 
1716 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1717 							    master, &dst,
1718 							    scores, hiscore_idx);
1719 
1720 			if (scores[hiscore_idx].ifa)
1721 				goto out;
1722 		}
1723 
1724 		for_each_netdev_rcu(net, dev) {
1725 			/* only consider addresses on devices in the
1726 			 * same L3 domain
1727 			 */
1728 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1729 				continue;
1730 			idev = __in6_dev_get(dev);
1731 			if (!idev)
1732 				continue;
1733 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1734 		}
1735 	}
1736 
1737 out:
1738 	hiscore = &scores[hiscore_idx];
1739 	if (!hiscore->ifa)
1740 		ret = -EADDRNOTAVAIL;
1741 	else
1742 		*saddr = hiscore->ifa->addr;
1743 
1744 	rcu_read_unlock();
1745 	return ret;
1746 }
1747 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1748 
1749 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1750 		      u32 banned_flags)
1751 {
1752 	struct inet6_ifaddr *ifp;
1753 	int err = -EADDRNOTAVAIL;
1754 
1755 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1756 		if (ifp->scope > IFA_LINK)
1757 			break;
1758 		if (ifp->scope == IFA_LINK &&
1759 		    !(ifp->flags & banned_flags)) {
1760 			*addr = ifp->addr;
1761 			err = 0;
1762 			break;
1763 		}
1764 	}
1765 	return err;
1766 }
1767 
1768 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1769 		    u32 banned_flags)
1770 {
1771 	struct inet6_dev *idev;
1772 	int err = -EADDRNOTAVAIL;
1773 
1774 	rcu_read_lock();
1775 	idev = __in6_dev_get(dev);
1776 	if (idev) {
1777 		read_lock_bh(&idev->lock);
1778 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1779 		read_unlock_bh(&idev->lock);
1780 	}
1781 	rcu_read_unlock();
1782 	return err;
1783 }
1784 
1785 static int ipv6_count_addresses(const struct inet6_dev *idev)
1786 {
1787 	const struct inet6_ifaddr *ifp;
1788 	int cnt = 0;
1789 
1790 	rcu_read_lock();
1791 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1792 		cnt++;
1793 	rcu_read_unlock();
1794 	return cnt;
1795 }
1796 
1797 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1798 		  const struct net_device *dev, int strict)
1799 {
1800 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1801 }
1802 EXPORT_SYMBOL(ipv6_chk_addr);
1803 
1804 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1805 			    const struct net_device *dev, int strict,
1806 			    u32 banned_flags)
1807 {
1808 	struct inet6_ifaddr *ifp;
1809 	unsigned int hash = inet6_addr_hash(addr);
1810 	u32 ifp_flags;
1811 
1812 	rcu_read_lock_bh();
1813 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1814 		if (!net_eq(dev_net(ifp->idev->dev), net))
1815 			continue;
1816 		/* Decouple optimistic from tentative for evaluation here.
1817 		 * Ban optimistic addresses explicitly, when required.
1818 		 */
1819 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1820 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1821 			    : ifp->flags;
1822 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1823 		    !(ifp_flags&banned_flags) &&
1824 		    (!dev || ifp->idev->dev == dev ||
1825 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1826 			rcu_read_unlock_bh();
1827 			return 1;
1828 		}
1829 	}
1830 
1831 	rcu_read_unlock_bh();
1832 	return 0;
1833 }
1834 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1835 
1836 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1837 			       struct net_device *dev)
1838 {
1839 	unsigned int hash = inet6_addr_hash(addr);
1840 	struct inet6_ifaddr *ifp;
1841 
1842 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1843 		if (!net_eq(dev_net(ifp->idev->dev), net))
1844 			continue;
1845 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1846 			if (!dev || ifp->idev->dev == dev)
1847 				return true;
1848 		}
1849 	}
1850 	return false;
1851 }
1852 
1853 /* Compares an address/prefix_len with addresses on device @dev.
1854  * If one is found it returns true.
1855  */
1856 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1857 	const unsigned int prefix_len, struct net_device *dev)
1858 {
1859 	const struct inet6_ifaddr *ifa;
1860 	const struct inet6_dev *idev;
1861 	bool ret = false;
1862 
1863 	rcu_read_lock();
1864 	idev = __in6_dev_get(dev);
1865 	if (idev) {
1866 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1867 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1868 			if (ret)
1869 				break;
1870 		}
1871 	}
1872 	rcu_read_unlock();
1873 
1874 	return ret;
1875 }
1876 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1877 
1878 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1879 {
1880 	const struct inet6_ifaddr *ifa;
1881 	const struct inet6_dev *idev;
1882 	int	onlink;
1883 
1884 	onlink = 0;
1885 	rcu_read_lock();
1886 	idev = __in6_dev_get(dev);
1887 	if (idev) {
1888 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1889 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1890 						   ifa->prefix_len);
1891 			if (onlink)
1892 				break;
1893 		}
1894 	}
1895 	rcu_read_unlock();
1896 	return onlink;
1897 }
1898 EXPORT_SYMBOL(ipv6_chk_prefix);
1899 
1900 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1901 				     struct net_device *dev, int strict)
1902 {
1903 	struct inet6_ifaddr *ifp, *result = NULL;
1904 	unsigned int hash = inet6_addr_hash(addr);
1905 
1906 	rcu_read_lock_bh();
1907 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1908 		if (!net_eq(dev_net(ifp->idev->dev), net))
1909 			continue;
1910 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1911 			if (!dev || ifp->idev->dev == dev ||
1912 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1913 				result = ifp;
1914 				in6_ifa_hold(ifp);
1915 				break;
1916 			}
1917 		}
1918 	}
1919 	rcu_read_unlock_bh();
1920 
1921 	return result;
1922 }
1923 
1924 /* Gets referenced address, destroys ifaddr */
1925 
1926 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1927 {
1928 	if (dad_failed)
1929 		ifp->flags |= IFA_F_DADFAILED;
1930 
1931 	if (ifp->flags&IFA_F_TEMPORARY) {
1932 		struct inet6_ifaddr *ifpub;
1933 		spin_lock_bh(&ifp->lock);
1934 		ifpub = ifp->ifpub;
1935 		if (ifpub) {
1936 			in6_ifa_hold(ifpub);
1937 			spin_unlock_bh(&ifp->lock);
1938 			ipv6_create_tempaddr(ifpub, ifp);
1939 			in6_ifa_put(ifpub);
1940 		} else {
1941 			spin_unlock_bh(&ifp->lock);
1942 		}
1943 		ipv6_del_addr(ifp);
1944 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1945 		spin_lock_bh(&ifp->lock);
1946 		addrconf_del_dad_work(ifp);
1947 		ifp->flags |= IFA_F_TENTATIVE;
1948 		spin_unlock_bh(&ifp->lock);
1949 		if (dad_failed)
1950 			ipv6_ifa_notify(0, ifp);
1951 		in6_ifa_put(ifp);
1952 	} else {
1953 		ipv6_del_addr(ifp);
1954 	}
1955 }
1956 
1957 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1958 {
1959 	int err = -ENOENT;
1960 
1961 	spin_lock_bh(&ifp->lock);
1962 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1963 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1964 		err = 0;
1965 	}
1966 	spin_unlock_bh(&ifp->lock);
1967 
1968 	return err;
1969 }
1970 
1971 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1972 {
1973 	struct inet6_dev *idev = ifp->idev;
1974 	struct net *net = dev_net(ifp->idev->dev);
1975 
1976 	if (addrconf_dad_end(ifp)) {
1977 		in6_ifa_put(ifp);
1978 		return;
1979 	}
1980 
1981 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1982 			     ifp->idev->dev->name, &ifp->addr);
1983 
1984 	spin_lock_bh(&ifp->lock);
1985 
1986 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1987 		int scope = ifp->scope;
1988 		u32 flags = ifp->flags;
1989 		struct in6_addr new_addr;
1990 		struct inet6_ifaddr *ifp2;
1991 		u32 valid_lft, preferred_lft;
1992 		int pfxlen = ifp->prefix_len;
1993 		int retries = ifp->stable_privacy_retry + 1;
1994 
1995 		if (retries > net->ipv6.sysctl.idgen_retries) {
1996 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
1997 					     ifp->idev->dev->name);
1998 			goto errdad;
1999 		}
2000 
2001 		new_addr = ifp->addr;
2002 		if (ipv6_generate_stable_address(&new_addr, retries,
2003 						 idev))
2004 			goto errdad;
2005 
2006 		valid_lft = ifp->valid_lft;
2007 		preferred_lft = ifp->prefered_lft;
2008 
2009 		spin_unlock_bh(&ifp->lock);
2010 
2011 		if (idev->cnf.max_addresses &&
2012 		    ipv6_count_addresses(idev) >=
2013 		    idev->cnf.max_addresses)
2014 			goto lock_errdad;
2015 
2016 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2017 				     ifp->idev->dev->name);
2018 
2019 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2020 				     scope, flags, valid_lft,
2021 				     preferred_lft);
2022 		if (IS_ERR(ifp2))
2023 			goto lock_errdad;
2024 
2025 		spin_lock_bh(&ifp2->lock);
2026 		ifp2->stable_privacy_retry = retries;
2027 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2028 		spin_unlock_bh(&ifp2->lock);
2029 
2030 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2031 		in6_ifa_put(ifp2);
2032 lock_errdad:
2033 		spin_lock_bh(&ifp->lock);
2034 	}
2035 
2036 errdad:
2037 	/* transition from _POSTDAD to _ERRDAD */
2038 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2039 	spin_unlock_bh(&ifp->lock);
2040 
2041 	addrconf_mod_dad_work(ifp, 0);
2042 	in6_ifa_put(ifp);
2043 }
2044 
2045 /* Join to solicited addr multicast group.
2046  * caller must hold RTNL */
2047 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2048 {
2049 	struct in6_addr maddr;
2050 
2051 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2052 		return;
2053 
2054 	addrconf_addr_solict_mult(addr, &maddr);
2055 	ipv6_dev_mc_inc(dev, &maddr);
2056 }
2057 
2058 /* caller must hold RTNL */
2059 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2060 {
2061 	struct in6_addr maddr;
2062 
2063 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2064 		return;
2065 
2066 	addrconf_addr_solict_mult(addr, &maddr);
2067 	__ipv6_dev_mc_dec(idev, &maddr);
2068 }
2069 
2070 /* caller must hold RTNL */
2071 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2072 {
2073 	struct in6_addr addr;
2074 
2075 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2076 		return;
2077 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2078 	if (ipv6_addr_any(&addr))
2079 		return;
2080 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2081 }
2082 
2083 /* caller must hold RTNL */
2084 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2085 {
2086 	struct in6_addr addr;
2087 
2088 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2089 		return;
2090 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2091 	if (ipv6_addr_any(&addr))
2092 		return;
2093 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2094 }
2095 
2096 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2097 {
2098 	switch (dev->addr_len) {
2099 	case ETH_ALEN:
2100 		memcpy(eui, dev->dev_addr, 3);
2101 		eui[3] = 0xFF;
2102 		eui[4] = 0xFE;
2103 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2104 		break;
2105 	case EUI64_ADDR_LEN:
2106 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2107 		eui[0] ^= 2;
2108 		break;
2109 	default:
2110 		return -1;
2111 	}
2112 
2113 	return 0;
2114 }
2115 
2116 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2117 {
2118 	union fwnet_hwaddr *ha;
2119 
2120 	if (dev->addr_len != FWNET_ALEN)
2121 		return -1;
2122 
2123 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2124 
2125 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2126 	eui[0] ^= 2;
2127 	return 0;
2128 }
2129 
2130 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2131 {
2132 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2133 	if (dev->addr_len != ARCNET_ALEN)
2134 		return -1;
2135 	memset(eui, 0, 7);
2136 	eui[7] = *(u8 *)dev->dev_addr;
2137 	return 0;
2138 }
2139 
2140 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2141 {
2142 	if (dev->addr_len != INFINIBAND_ALEN)
2143 		return -1;
2144 	memcpy(eui, dev->dev_addr + 12, 8);
2145 	eui[0] |= 2;
2146 	return 0;
2147 }
2148 
2149 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2150 {
2151 	if (addr == 0)
2152 		return -1;
2153 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2154 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2155 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2156 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2157 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2158 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2159 	eui[1] = 0;
2160 	eui[2] = 0x5E;
2161 	eui[3] = 0xFE;
2162 	memcpy(eui + 4, &addr, 4);
2163 	return 0;
2164 }
2165 
2166 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2167 {
2168 	if (dev->priv_flags & IFF_ISATAP)
2169 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2170 	return -1;
2171 }
2172 
2173 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2174 {
2175 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2176 }
2177 
2178 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2179 {
2180 	memcpy(eui, dev->perm_addr, 3);
2181 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2182 	eui[3] = 0xFF;
2183 	eui[4] = 0xFE;
2184 	eui[0] ^= 2;
2185 	return 0;
2186 }
2187 
2188 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2189 {
2190 	switch (dev->type) {
2191 	case ARPHRD_ETHER:
2192 	case ARPHRD_FDDI:
2193 		return addrconf_ifid_eui48(eui, dev);
2194 	case ARPHRD_ARCNET:
2195 		return addrconf_ifid_arcnet(eui, dev);
2196 	case ARPHRD_INFINIBAND:
2197 		return addrconf_ifid_infiniband(eui, dev);
2198 	case ARPHRD_SIT:
2199 		return addrconf_ifid_sit(eui, dev);
2200 	case ARPHRD_IPGRE:
2201 	case ARPHRD_TUNNEL:
2202 		return addrconf_ifid_gre(eui, dev);
2203 	case ARPHRD_6LOWPAN:
2204 		return addrconf_ifid_6lowpan(eui, dev);
2205 	case ARPHRD_IEEE1394:
2206 		return addrconf_ifid_ieee1394(eui, dev);
2207 	case ARPHRD_TUNNEL6:
2208 	case ARPHRD_IP6GRE:
2209 		return addrconf_ifid_ip6tnl(eui, dev);
2210 	}
2211 	return -1;
2212 }
2213 
2214 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2215 {
2216 	int err = -1;
2217 	struct inet6_ifaddr *ifp;
2218 
2219 	read_lock_bh(&idev->lock);
2220 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2221 		if (ifp->scope > IFA_LINK)
2222 			break;
2223 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2224 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2225 			err = 0;
2226 			break;
2227 		}
2228 	}
2229 	read_unlock_bh(&idev->lock);
2230 	return err;
2231 }
2232 
2233 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2234 static void ipv6_regen_rndid(struct inet6_dev *idev)
2235 {
2236 regen:
2237 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2238 	idev->rndid[0] &= ~0x02;
2239 
2240 	/*
2241 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2242 	 * check if generated address is not inappropriate
2243 	 *
2244 	 *  - Reserved subnet anycast (RFC 2526)
2245 	 *	11111101 11....11 1xxxxxxx
2246 	 *  - ISATAP (RFC4214) 6.1
2247 	 *	00-00-5E-FE-xx-xx-xx-xx
2248 	 *  - value 0
2249 	 *  - XXX: already assigned to an address on the device
2250 	 */
2251 	if (idev->rndid[0] == 0xfd &&
2252 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2253 	    (idev->rndid[7]&0x80))
2254 		goto regen;
2255 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2256 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2257 			goto regen;
2258 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2259 			goto regen;
2260 	}
2261 }
2262 
2263 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2264 {
2265 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2266 		ipv6_regen_rndid(idev);
2267 }
2268 
2269 /*
2270  *	Add prefix route.
2271  */
2272 
2273 static void
2274 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2275 		      unsigned long expires, u32 flags)
2276 {
2277 	struct fib6_config cfg = {
2278 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2279 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2280 		.fc_ifindex = dev->ifindex,
2281 		.fc_expires = expires,
2282 		.fc_dst_len = plen,
2283 		.fc_flags = RTF_UP | flags,
2284 		.fc_nlinfo.nl_net = dev_net(dev),
2285 		.fc_protocol = RTPROT_KERNEL,
2286 	};
2287 
2288 	cfg.fc_dst = *pfx;
2289 
2290 	/* Prevent useless cloning on PtP SIT.
2291 	   This thing is done here expecting that the whole
2292 	   class of non-broadcast devices need not cloning.
2293 	 */
2294 #if IS_ENABLED(CONFIG_IPV6_SIT)
2295 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2296 		cfg.fc_flags |= RTF_NONEXTHOP;
2297 #endif
2298 
2299 	ip6_route_add(&cfg, NULL);
2300 }
2301 
2302 
2303 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2304 						  int plen,
2305 						  const struct net_device *dev,
2306 						  u32 flags, u32 noflags)
2307 {
2308 	struct fib6_node *fn;
2309 	struct rt6_info *rt = NULL;
2310 	struct fib6_table *table;
2311 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2312 
2313 	table = fib6_get_table(dev_net(dev), tb_id);
2314 	if (!table)
2315 		return NULL;
2316 
2317 	rcu_read_lock();
2318 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2319 	if (!fn)
2320 		goto out;
2321 
2322 	for_each_fib6_node_rt_rcu(fn) {
2323 		if (rt->dst.dev->ifindex != dev->ifindex)
2324 			continue;
2325 		if ((rt->rt6i_flags & flags) != flags)
2326 			continue;
2327 		if ((rt->rt6i_flags & noflags) != 0)
2328 			continue;
2329 		if (!dst_hold_safe(&rt->dst))
2330 			rt = NULL;
2331 		break;
2332 	}
2333 out:
2334 	rcu_read_unlock();
2335 	return rt;
2336 }
2337 
2338 
2339 /* Create "default" multicast route to the interface */
2340 
2341 static void addrconf_add_mroute(struct net_device *dev)
2342 {
2343 	struct fib6_config cfg = {
2344 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2345 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2346 		.fc_ifindex = dev->ifindex,
2347 		.fc_dst_len = 8,
2348 		.fc_flags = RTF_UP,
2349 		.fc_nlinfo.nl_net = dev_net(dev),
2350 	};
2351 
2352 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2353 
2354 	ip6_route_add(&cfg, NULL);
2355 }
2356 
2357 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2358 {
2359 	struct inet6_dev *idev;
2360 
2361 	ASSERT_RTNL();
2362 
2363 	idev = ipv6_find_idev(dev);
2364 	if (!idev)
2365 		return ERR_PTR(-ENOBUFS);
2366 
2367 	if (idev->cnf.disable_ipv6)
2368 		return ERR_PTR(-EACCES);
2369 
2370 	/* Add default multicast route */
2371 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2372 		addrconf_add_mroute(dev);
2373 
2374 	return idev;
2375 }
2376 
2377 static void manage_tempaddrs(struct inet6_dev *idev,
2378 			     struct inet6_ifaddr *ifp,
2379 			     __u32 valid_lft, __u32 prefered_lft,
2380 			     bool create, unsigned long now)
2381 {
2382 	u32 flags;
2383 	struct inet6_ifaddr *ift;
2384 
2385 	read_lock_bh(&idev->lock);
2386 	/* update all temporary addresses in the list */
2387 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2388 		int age, max_valid, max_prefered;
2389 
2390 		if (ifp != ift->ifpub)
2391 			continue;
2392 
2393 		/* RFC 4941 section 3.3:
2394 		 * If a received option will extend the lifetime of a public
2395 		 * address, the lifetimes of temporary addresses should
2396 		 * be extended, subject to the overall constraint that no
2397 		 * temporary addresses should ever remain "valid" or "preferred"
2398 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2399 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2400 		 */
2401 		age = (now - ift->cstamp) / HZ;
2402 		max_valid = idev->cnf.temp_valid_lft - age;
2403 		if (max_valid < 0)
2404 			max_valid = 0;
2405 
2406 		max_prefered = idev->cnf.temp_prefered_lft -
2407 			       idev->desync_factor - age;
2408 		if (max_prefered < 0)
2409 			max_prefered = 0;
2410 
2411 		if (valid_lft > max_valid)
2412 			valid_lft = max_valid;
2413 
2414 		if (prefered_lft > max_prefered)
2415 			prefered_lft = max_prefered;
2416 
2417 		spin_lock(&ift->lock);
2418 		flags = ift->flags;
2419 		ift->valid_lft = valid_lft;
2420 		ift->prefered_lft = prefered_lft;
2421 		ift->tstamp = now;
2422 		if (prefered_lft > 0)
2423 			ift->flags &= ~IFA_F_DEPRECATED;
2424 
2425 		spin_unlock(&ift->lock);
2426 		if (!(flags&IFA_F_TENTATIVE))
2427 			ipv6_ifa_notify(0, ift);
2428 	}
2429 
2430 	if ((create || list_empty(&idev->tempaddr_list)) &&
2431 	    idev->cnf.use_tempaddr > 0) {
2432 		/* When a new public address is created as described
2433 		 * in [ADDRCONF], also create a new temporary address.
2434 		 * Also create a temporary address if it's enabled but
2435 		 * no temporary address currently exists.
2436 		 */
2437 		read_unlock_bh(&idev->lock);
2438 		ipv6_create_tempaddr(ifp, NULL);
2439 	} else {
2440 		read_unlock_bh(&idev->lock);
2441 	}
2442 }
2443 
2444 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2445 {
2446 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2447 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2448 }
2449 
2450 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2451 				 const struct prefix_info *pinfo,
2452 				 struct inet6_dev *in6_dev,
2453 				 const struct in6_addr *addr, int addr_type,
2454 				 u32 addr_flags, bool sllao, bool tokenized,
2455 				 __u32 valid_lft, u32 prefered_lft)
2456 {
2457 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2458 	int create = 0, update_lft = 0;
2459 
2460 	if (!ifp && valid_lft) {
2461 		int max_addresses = in6_dev->cnf.max_addresses;
2462 
2463 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2464 		if ((net->ipv6.devconf_all->optimistic_dad ||
2465 		     in6_dev->cnf.optimistic_dad) &&
2466 		    !net->ipv6.devconf_all->forwarding && sllao)
2467 			addr_flags |= IFA_F_OPTIMISTIC;
2468 #endif
2469 
2470 		/* Do not allow to create too much of autoconfigured
2471 		 * addresses; this would be too easy way to crash kernel.
2472 		 */
2473 		if (!max_addresses ||
2474 		    ipv6_count_addresses(in6_dev) < max_addresses)
2475 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2476 					    pinfo->prefix_len,
2477 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2478 					    addr_flags, valid_lft,
2479 					    prefered_lft);
2480 
2481 		if (IS_ERR_OR_NULL(ifp))
2482 			return -1;
2483 
2484 		update_lft = 0;
2485 		create = 1;
2486 		spin_lock_bh(&ifp->lock);
2487 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2488 		ifp->cstamp = jiffies;
2489 		ifp->tokenized = tokenized;
2490 		spin_unlock_bh(&ifp->lock);
2491 		addrconf_dad_start(ifp);
2492 	}
2493 
2494 	if (ifp) {
2495 		u32 flags;
2496 		unsigned long now;
2497 		u32 stored_lft;
2498 
2499 		/* update lifetime (RFC2462 5.5.3 e) */
2500 		spin_lock_bh(&ifp->lock);
2501 		now = jiffies;
2502 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2503 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2504 		else
2505 			stored_lft = 0;
2506 		if (!update_lft && !create && stored_lft) {
2507 			const u32 minimum_lft = min_t(u32,
2508 				stored_lft, MIN_VALID_LIFETIME);
2509 			valid_lft = max(valid_lft, minimum_lft);
2510 
2511 			/* RFC4862 Section 5.5.3e:
2512 			 * "Note that the preferred lifetime of the
2513 			 *  corresponding address is always reset to
2514 			 *  the Preferred Lifetime in the received
2515 			 *  Prefix Information option, regardless of
2516 			 *  whether the valid lifetime is also reset or
2517 			 *  ignored."
2518 			 *
2519 			 * So we should always update prefered_lft here.
2520 			 */
2521 			update_lft = 1;
2522 		}
2523 
2524 		if (update_lft) {
2525 			ifp->valid_lft = valid_lft;
2526 			ifp->prefered_lft = prefered_lft;
2527 			ifp->tstamp = now;
2528 			flags = ifp->flags;
2529 			ifp->flags &= ~IFA_F_DEPRECATED;
2530 			spin_unlock_bh(&ifp->lock);
2531 
2532 			if (!(flags&IFA_F_TENTATIVE))
2533 				ipv6_ifa_notify(0, ifp);
2534 		} else
2535 			spin_unlock_bh(&ifp->lock);
2536 
2537 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2538 				 create, now);
2539 
2540 		in6_ifa_put(ifp);
2541 		addrconf_verify();
2542 	}
2543 
2544 	return 0;
2545 }
2546 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2547 
2548 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2549 {
2550 	struct prefix_info *pinfo;
2551 	__u32 valid_lft;
2552 	__u32 prefered_lft;
2553 	int addr_type, err;
2554 	u32 addr_flags = 0;
2555 	struct inet6_dev *in6_dev;
2556 	struct net *net = dev_net(dev);
2557 
2558 	pinfo = (struct prefix_info *) opt;
2559 
2560 	if (len < sizeof(struct prefix_info)) {
2561 		ADBG("addrconf: prefix option too short\n");
2562 		return;
2563 	}
2564 
2565 	/*
2566 	 *	Validation checks ([ADDRCONF], page 19)
2567 	 */
2568 
2569 	addr_type = ipv6_addr_type(&pinfo->prefix);
2570 
2571 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2572 		return;
2573 
2574 	valid_lft = ntohl(pinfo->valid);
2575 	prefered_lft = ntohl(pinfo->prefered);
2576 
2577 	if (prefered_lft > valid_lft) {
2578 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2579 		return;
2580 	}
2581 
2582 	in6_dev = in6_dev_get(dev);
2583 
2584 	if (!in6_dev) {
2585 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2586 				    dev->name);
2587 		return;
2588 	}
2589 
2590 	/*
2591 	 *	Two things going on here:
2592 	 *	1) Add routes for on-link prefixes
2593 	 *	2) Configure prefixes with the auto flag set
2594 	 */
2595 
2596 	if (pinfo->onlink) {
2597 		struct rt6_info *rt;
2598 		unsigned long rt_expires;
2599 
2600 		/* Avoid arithmetic overflow. Really, we could
2601 		 * save rt_expires in seconds, likely valid_lft,
2602 		 * but it would require division in fib gc, that it
2603 		 * not good.
2604 		 */
2605 		if (HZ > USER_HZ)
2606 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2607 		else
2608 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2609 
2610 		if (addrconf_finite_timeout(rt_expires))
2611 			rt_expires *= HZ;
2612 
2613 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2614 					       pinfo->prefix_len,
2615 					       dev,
2616 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2617 					       RTF_GATEWAY | RTF_DEFAULT);
2618 
2619 		if (rt) {
2620 			/* Autoconf prefix route */
2621 			if (valid_lft == 0) {
2622 				ip6_del_rt(rt);
2623 				rt = NULL;
2624 			} else if (addrconf_finite_timeout(rt_expires)) {
2625 				/* not infinity */
2626 				rt6_set_expires(rt, jiffies + rt_expires);
2627 			} else {
2628 				rt6_clean_expires(rt);
2629 			}
2630 		} else if (valid_lft) {
2631 			clock_t expires = 0;
2632 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2633 			if (addrconf_finite_timeout(rt_expires)) {
2634 				/* not infinity */
2635 				flags |= RTF_EXPIRES;
2636 				expires = jiffies_to_clock_t(rt_expires);
2637 			}
2638 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2639 					      dev, expires, flags);
2640 		}
2641 		ip6_rt_put(rt);
2642 	}
2643 
2644 	/* Try to figure out our local address for this prefix */
2645 
2646 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2647 		struct in6_addr addr;
2648 		bool tokenized = false, dev_addr_generated = false;
2649 
2650 		if (pinfo->prefix_len == 64) {
2651 			memcpy(&addr, &pinfo->prefix, 8);
2652 
2653 			if (!ipv6_addr_any(&in6_dev->token)) {
2654 				read_lock_bh(&in6_dev->lock);
2655 				memcpy(addr.s6_addr + 8,
2656 				       in6_dev->token.s6_addr + 8, 8);
2657 				read_unlock_bh(&in6_dev->lock);
2658 				tokenized = true;
2659 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2660 				   !ipv6_generate_stable_address(&addr, 0,
2661 								 in6_dev)) {
2662 				addr_flags |= IFA_F_STABLE_PRIVACY;
2663 				goto ok;
2664 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2665 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2666 				goto put;
2667 			} else {
2668 				dev_addr_generated = true;
2669 			}
2670 			goto ok;
2671 		}
2672 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2673 				    pinfo->prefix_len);
2674 		goto put;
2675 
2676 ok:
2677 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2678 						   &addr, addr_type,
2679 						   addr_flags, sllao,
2680 						   tokenized, valid_lft,
2681 						   prefered_lft);
2682 		if (err)
2683 			goto put;
2684 
2685 		/* Ignore error case here because previous prefix add addr was
2686 		 * successful which will be notified.
2687 		 */
2688 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2689 					      addr_type, addr_flags, sllao,
2690 					      tokenized, valid_lft,
2691 					      prefered_lft,
2692 					      dev_addr_generated);
2693 	}
2694 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2695 put:
2696 	in6_dev_put(in6_dev);
2697 }
2698 
2699 /*
2700  *	Set destination address.
2701  *	Special case for SIT interfaces where we create a new "virtual"
2702  *	device.
2703  */
2704 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2705 {
2706 	struct in6_ifreq ireq;
2707 	struct net_device *dev;
2708 	int err = -EINVAL;
2709 
2710 	rtnl_lock();
2711 
2712 	err = -EFAULT;
2713 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2714 		goto err_exit;
2715 
2716 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2717 
2718 	err = -ENODEV;
2719 	if (!dev)
2720 		goto err_exit;
2721 
2722 #if IS_ENABLED(CONFIG_IPV6_SIT)
2723 	if (dev->type == ARPHRD_SIT) {
2724 		const struct net_device_ops *ops = dev->netdev_ops;
2725 		struct ifreq ifr;
2726 		struct ip_tunnel_parm p;
2727 
2728 		err = -EADDRNOTAVAIL;
2729 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2730 			goto err_exit;
2731 
2732 		memset(&p, 0, sizeof(p));
2733 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2734 		p.iph.saddr = 0;
2735 		p.iph.version = 4;
2736 		p.iph.ihl = 5;
2737 		p.iph.protocol = IPPROTO_IPV6;
2738 		p.iph.ttl = 64;
2739 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2740 
2741 		if (ops->ndo_do_ioctl) {
2742 			mm_segment_t oldfs = get_fs();
2743 
2744 			set_fs(KERNEL_DS);
2745 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2746 			set_fs(oldfs);
2747 		} else
2748 			err = -EOPNOTSUPP;
2749 
2750 		if (err == 0) {
2751 			err = -ENOBUFS;
2752 			dev = __dev_get_by_name(net, p.name);
2753 			if (!dev)
2754 				goto err_exit;
2755 			err = dev_open(dev);
2756 		}
2757 	}
2758 #endif
2759 
2760 err_exit:
2761 	rtnl_unlock();
2762 	return err;
2763 }
2764 
2765 static int ipv6_mc_config(struct sock *sk, bool join,
2766 			  const struct in6_addr *addr, int ifindex)
2767 {
2768 	int ret;
2769 
2770 	ASSERT_RTNL();
2771 
2772 	lock_sock(sk);
2773 	if (join)
2774 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2775 	else
2776 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2777 	release_sock(sk);
2778 
2779 	return ret;
2780 }
2781 
2782 /*
2783  *	Manual configuration of address on an interface
2784  */
2785 static int inet6_addr_add(struct net *net, int ifindex,
2786 			  const struct in6_addr *pfx,
2787 			  const struct in6_addr *peer_pfx,
2788 			  unsigned int plen, __u32 ifa_flags,
2789 			  __u32 prefered_lft, __u32 valid_lft)
2790 {
2791 	struct inet6_ifaddr *ifp;
2792 	struct inet6_dev *idev;
2793 	struct net_device *dev;
2794 	unsigned long timeout;
2795 	clock_t expires;
2796 	int scope;
2797 	u32 flags;
2798 
2799 	ASSERT_RTNL();
2800 
2801 	if (plen > 128)
2802 		return -EINVAL;
2803 
2804 	/* check the lifetime */
2805 	if (!valid_lft || prefered_lft > valid_lft)
2806 		return -EINVAL;
2807 
2808 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2809 		return -EINVAL;
2810 
2811 	dev = __dev_get_by_index(net, ifindex);
2812 	if (!dev)
2813 		return -ENODEV;
2814 
2815 	idev = addrconf_add_dev(dev);
2816 	if (IS_ERR(idev))
2817 		return PTR_ERR(idev);
2818 
2819 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2820 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2821 					 true, pfx, ifindex);
2822 
2823 		if (ret < 0)
2824 			return ret;
2825 	}
2826 
2827 	scope = ipv6_addr_scope(pfx);
2828 
2829 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2830 	if (addrconf_finite_timeout(timeout)) {
2831 		expires = jiffies_to_clock_t(timeout * HZ);
2832 		valid_lft = timeout;
2833 		flags = RTF_EXPIRES;
2834 	} else {
2835 		expires = 0;
2836 		flags = 0;
2837 		ifa_flags |= IFA_F_PERMANENT;
2838 	}
2839 
2840 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2841 	if (addrconf_finite_timeout(timeout)) {
2842 		if (timeout == 0)
2843 			ifa_flags |= IFA_F_DEPRECATED;
2844 		prefered_lft = timeout;
2845 	}
2846 
2847 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2848 			    valid_lft, prefered_lft);
2849 
2850 	if (!IS_ERR(ifp)) {
2851 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2852 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2853 					      expires, flags);
2854 		}
2855 
2856 		/*
2857 		 * Note that section 3.1 of RFC 4429 indicates
2858 		 * that the Optimistic flag should not be set for
2859 		 * manually configured addresses
2860 		 */
2861 		addrconf_dad_start(ifp);
2862 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2863 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2864 					 true, jiffies);
2865 		in6_ifa_put(ifp);
2866 		addrconf_verify_rtnl();
2867 		return 0;
2868 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2869 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2870 			       false, pfx, ifindex);
2871 	}
2872 
2873 	return PTR_ERR(ifp);
2874 }
2875 
2876 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2877 			  const struct in6_addr *pfx, unsigned int plen)
2878 {
2879 	struct inet6_ifaddr *ifp;
2880 	struct inet6_dev *idev;
2881 	struct net_device *dev;
2882 
2883 	if (plen > 128)
2884 		return -EINVAL;
2885 
2886 	dev = __dev_get_by_index(net, ifindex);
2887 	if (!dev)
2888 		return -ENODEV;
2889 
2890 	idev = __in6_dev_get(dev);
2891 	if (!idev)
2892 		return -ENXIO;
2893 
2894 	read_lock_bh(&idev->lock);
2895 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2896 		if (ifp->prefix_len == plen &&
2897 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2898 			in6_ifa_hold(ifp);
2899 			read_unlock_bh(&idev->lock);
2900 
2901 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2902 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2903 				manage_tempaddrs(idev, ifp, 0, 0, false,
2904 						 jiffies);
2905 			ipv6_del_addr(ifp);
2906 			addrconf_verify_rtnl();
2907 			if (ipv6_addr_is_multicast(pfx)) {
2908 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2909 					       false, pfx, dev->ifindex);
2910 			}
2911 			return 0;
2912 		}
2913 	}
2914 	read_unlock_bh(&idev->lock);
2915 	return -EADDRNOTAVAIL;
2916 }
2917 
2918 
2919 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2920 {
2921 	struct in6_ifreq ireq;
2922 	int err;
2923 
2924 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2925 		return -EPERM;
2926 
2927 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2928 		return -EFAULT;
2929 
2930 	rtnl_lock();
2931 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2932 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2933 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2934 	rtnl_unlock();
2935 	return err;
2936 }
2937 
2938 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2939 {
2940 	struct in6_ifreq ireq;
2941 	int err;
2942 
2943 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2944 		return -EPERM;
2945 
2946 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2947 		return -EFAULT;
2948 
2949 	rtnl_lock();
2950 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2951 			     ireq.ifr6_prefixlen);
2952 	rtnl_unlock();
2953 	return err;
2954 }
2955 
2956 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2957 		     int plen, int scope)
2958 {
2959 	struct inet6_ifaddr *ifp;
2960 
2961 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2962 			    scope, IFA_F_PERMANENT,
2963 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2964 	if (!IS_ERR(ifp)) {
2965 		spin_lock_bh(&ifp->lock);
2966 		ifp->flags &= ~IFA_F_TENTATIVE;
2967 		spin_unlock_bh(&ifp->lock);
2968 		rt_genid_bump_ipv6(dev_net(idev->dev));
2969 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2970 		in6_ifa_put(ifp);
2971 	}
2972 }
2973 
2974 #if IS_ENABLED(CONFIG_IPV6_SIT)
2975 static void sit_add_v4_addrs(struct inet6_dev *idev)
2976 {
2977 	struct in6_addr addr;
2978 	struct net_device *dev;
2979 	struct net *net = dev_net(idev->dev);
2980 	int scope, plen;
2981 	u32 pflags = 0;
2982 
2983 	ASSERT_RTNL();
2984 
2985 	memset(&addr, 0, sizeof(struct in6_addr));
2986 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2987 
2988 	if (idev->dev->flags&IFF_POINTOPOINT) {
2989 		addr.s6_addr32[0] = htonl(0xfe800000);
2990 		scope = IFA_LINK;
2991 		plen = 64;
2992 	} else {
2993 		scope = IPV6_ADDR_COMPATv4;
2994 		plen = 96;
2995 		pflags |= RTF_NONEXTHOP;
2996 	}
2997 
2998 	if (addr.s6_addr32[3]) {
2999 		add_addr(idev, &addr, plen, scope);
3000 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
3001 		return;
3002 	}
3003 
3004 	for_each_netdev(net, dev) {
3005 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3006 		if (in_dev && (dev->flags & IFF_UP)) {
3007 			struct in_ifaddr *ifa;
3008 
3009 			int flag = scope;
3010 
3011 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3012 
3013 				addr.s6_addr32[3] = ifa->ifa_local;
3014 
3015 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3016 					continue;
3017 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3018 					if (idev->dev->flags&IFF_POINTOPOINT)
3019 						continue;
3020 					flag |= IFA_HOST;
3021 				}
3022 
3023 				add_addr(idev, &addr, plen, flag);
3024 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3025 						      pflags);
3026 			}
3027 		}
3028 	}
3029 }
3030 #endif
3031 
3032 static void init_loopback(struct net_device *dev)
3033 {
3034 	struct inet6_dev  *idev;
3035 
3036 	/* ::1 */
3037 
3038 	ASSERT_RTNL();
3039 
3040 	idev = ipv6_find_idev(dev);
3041 	if (!idev) {
3042 		pr_debug("%s: add_dev failed\n", __func__);
3043 		return;
3044 	}
3045 
3046 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3047 }
3048 
3049 void addrconf_add_linklocal(struct inet6_dev *idev,
3050 			    const struct in6_addr *addr, u32 flags)
3051 {
3052 	struct inet6_ifaddr *ifp;
3053 	u32 addr_flags = flags | IFA_F_PERMANENT;
3054 
3055 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3056 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3057 	     idev->cnf.optimistic_dad) &&
3058 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3059 		addr_flags |= IFA_F_OPTIMISTIC;
3060 #endif
3061 
3062 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3063 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
3064 	if (!IS_ERR(ifp)) {
3065 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3066 		addrconf_dad_start(ifp);
3067 		in6_ifa_put(ifp);
3068 	}
3069 }
3070 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3071 
3072 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3073 {
3074 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3075 		return true;
3076 
3077 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3078 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3079 		return true;
3080 
3081 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3082 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3083 		return true;
3084 
3085 	return false;
3086 }
3087 
3088 static int ipv6_generate_stable_address(struct in6_addr *address,
3089 					u8 dad_count,
3090 					const struct inet6_dev *idev)
3091 {
3092 	static DEFINE_SPINLOCK(lock);
3093 	static __u32 digest[SHA_DIGEST_WORDS];
3094 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3095 
3096 	static union {
3097 		char __data[SHA_MESSAGE_BYTES];
3098 		struct {
3099 			struct in6_addr secret;
3100 			__be32 prefix[2];
3101 			unsigned char hwaddr[MAX_ADDR_LEN];
3102 			u8 dad_count;
3103 		} __packed;
3104 	} data;
3105 
3106 	struct in6_addr secret;
3107 	struct in6_addr temp;
3108 	struct net *net = dev_net(idev->dev);
3109 
3110 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3111 
3112 	if (idev->cnf.stable_secret.initialized)
3113 		secret = idev->cnf.stable_secret.secret;
3114 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3115 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3116 	else
3117 		return -1;
3118 
3119 retry:
3120 	spin_lock_bh(&lock);
3121 
3122 	sha_init(digest);
3123 	memset(&data, 0, sizeof(data));
3124 	memset(workspace, 0, sizeof(workspace));
3125 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3126 	data.prefix[0] = address->s6_addr32[0];
3127 	data.prefix[1] = address->s6_addr32[1];
3128 	data.secret = secret;
3129 	data.dad_count = dad_count;
3130 
3131 	sha_transform(digest, data.__data, workspace);
3132 
3133 	temp = *address;
3134 	temp.s6_addr32[2] = (__force __be32)digest[0];
3135 	temp.s6_addr32[3] = (__force __be32)digest[1];
3136 
3137 	spin_unlock_bh(&lock);
3138 
3139 	if (ipv6_reserved_interfaceid(temp)) {
3140 		dad_count++;
3141 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3142 			return -1;
3143 		goto retry;
3144 	}
3145 
3146 	*address = temp;
3147 	return 0;
3148 }
3149 
3150 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3151 {
3152 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3153 
3154 	if (s->initialized)
3155 		return;
3156 	s = &idev->cnf.stable_secret;
3157 	get_random_bytes(&s->secret, sizeof(s->secret));
3158 	s->initialized = true;
3159 }
3160 
3161 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3162 {
3163 	struct in6_addr addr;
3164 
3165 	/* no link local addresses on L3 master devices */
3166 	if (netif_is_l3_master(idev->dev))
3167 		return;
3168 
3169 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3170 
3171 	switch (idev->cnf.addr_gen_mode) {
3172 	case IN6_ADDR_GEN_MODE_RANDOM:
3173 		ipv6_gen_mode_random_init(idev);
3174 		/* fallthrough */
3175 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3176 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3177 			addrconf_add_linklocal(idev, &addr,
3178 					       IFA_F_STABLE_PRIVACY);
3179 		else if (prefix_route)
3180 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3181 		break;
3182 	case IN6_ADDR_GEN_MODE_EUI64:
3183 		/* addrconf_add_linklocal also adds a prefix_route and we
3184 		 * only need to care about prefix routes if ipv6_generate_eui64
3185 		 * couldn't generate one.
3186 		 */
3187 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3188 			addrconf_add_linklocal(idev, &addr, 0);
3189 		else if (prefix_route)
3190 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3191 		break;
3192 	case IN6_ADDR_GEN_MODE_NONE:
3193 	default:
3194 		/* will not add any link local address */
3195 		break;
3196 	}
3197 }
3198 
3199 static void addrconf_dev_config(struct net_device *dev)
3200 {
3201 	struct inet6_dev *idev;
3202 
3203 	ASSERT_RTNL();
3204 
3205 	if ((dev->type != ARPHRD_ETHER) &&
3206 	    (dev->type != ARPHRD_FDDI) &&
3207 	    (dev->type != ARPHRD_ARCNET) &&
3208 	    (dev->type != ARPHRD_INFINIBAND) &&
3209 	    (dev->type != ARPHRD_IEEE1394) &&
3210 	    (dev->type != ARPHRD_TUNNEL6) &&
3211 	    (dev->type != ARPHRD_6LOWPAN) &&
3212 	    (dev->type != ARPHRD_IP6GRE) &&
3213 	    (dev->type != ARPHRD_IPGRE) &&
3214 	    (dev->type != ARPHRD_TUNNEL) &&
3215 	    (dev->type != ARPHRD_NONE)) {
3216 		/* Alas, we support only Ethernet autoconfiguration. */
3217 		return;
3218 	}
3219 
3220 	idev = addrconf_add_dev(dev);
3221 	if (IS_ERR(idev))
3222 		return;
3223 
3224 	/* this device type has no EUI support */
3225 	if (dev->type == ARPHRD_NONE &&
3226 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3227 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3228 
3229 	addrconf_addr_gen(idev, false);
3230 }
3231 
3232 #if IS_ENABLED(CONFIG_IPV6_SIT)
3233 static void addrconf_sit_config(struct net_device *dev)
3234 {
3235 	struct inet6_dev *idev;
3236 
3237 	ASSERT_RTNL();
3238 
3239 	/*
3240 	 * Configure the tunnel with one of our IPv4
3241 	 * addresses... we should configure all of
3242 	 * our v4 addrs in the tunnel
3243 	 */
3244 
3245 	idev = ipv6_find_idev(dev);
3246 	if (!idev) {
3247 		pr_debug("%s: add_dev failed\n", __func__);
3248 		return;
3249 	}
3250 
3251 	if (dev->priv_flags & IFF_ISATAP) {
3252 		addrconf_addr_gen(idev, false);
3253 		return;
3254 	}
3255 
3256 	sit_add_v4_addrs(idev);
3257 
3258 	if (dev->flags&IFF_POINTOPOINT)
3259 		addrconf_add_mroute(dev);
3260 }
3261 #endif
3262 
3263 #if IS_ENABLED(CONFIG_NET_IPGRE)
3264 static void addrconf_gre_config(struct net_device *dev)
3265 {
3266 	struct inet6_dev *idev;
3267 
3268 	ASSERT_RTNL();
3269 
3270 	idev = ipv6_find_idev(dev);
3271 	if (!idev) {
3272 		pr_debug("%s: add_dev failed\n", __func__);
3273 		return;
3274 	}
3275 
3276 	addrconf_addr_gen(idev, true);
3277 	if (dev->flags & IFF_POINTOPOINT)
3278 		addrconf_add_mroute(dev);
3279 }
3280 #endif
3281 
3282 static int fixup_permanent_addr(struct inet6_dev *idev,
3283 				struct inet6_ifaddr *ifp)
3284 {
3285 	/* !rt6i_node means the host route was removed from the
3286 	 * FIB, for example, if 'lo' device is taken down. In that
3287 	 * case regenerate the host route.
3288 	 */
3289 	if (!ifp->rt || !ifp->rt->rt6i_node) {
3290 		struct rt6_info *rt, *prev;
3291 
3292 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3293 		if (IS_ERR(rt))
3294 			return PTR_ERR(rt);
3295 
3296 		/* ifp->rt can be accessed outside of rtnl */
3297 		spin_lock(&ifp->lock);
3298 		prev = ifp->rt;
3299 		ifp->rt = rt;
3300 		spin_unlock(&ifp->lock);
3301 
3302 		ip6_rt_put(prev);
3303 	}
3304 
3305 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3306 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3307 				      idev->dev, 0, 0);
3308 	}
3309 
3310 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3311 		addrconf_dad_start(ifp);
3312 
3313 	return 0;
3314 }
3315 
3316 static void addrconf_permanent_addr(struct net_device *dev)
3317 {
3318 	struct inet6_ifaddr *ifp, *tmp;
3319 	struct inet6_dev *idev;
3320 
3321 	idev = __in6_dev_get(dev);
3322 	if (!idev)
3323 		return;
3324 
3325 	write_lock_bh(&idev->lock);
3326 
3327 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3328 		if ((ifp->flags & IFA_F_PERMANENT) &&
3329 		    fixup_permanent_addr(idev, ifp) < 0) {
3330 			write_unlock_bh(&idev->lock);
3331 			ipv6_del_addr(ifp);
3332 			write_lock_bh(&idev->lock);
3333 
3334 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3335 					     idev->dev->name, &ifp->addr);
3336 		}
3337 	}
3338 
3339 	write_unlock_bh(&idev->lock);
3340 }
3341 
3342 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3343 			   void *ptr)
3344 {
3345 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3346 	struct netdev_notifier_changeupper_info *info;
3347 	struct inet6_dev *idev = __in6_dev_get(dev);
3348 	struct net *net = dev_net(dev);
3349 	int run_pending = 0;
3350 	int err;
3351 
3352 	switch (event) {
3353 	case NETDEV_REGISTER:
3354 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3355 			idev = ipv6_add_dev(dev);
3356 			if (IS_ERR(idev))
3357 				return notifier_from_errno(PTR_ERR(idev));
3358 		}
3359 		break;
3360 
3361 	case NETDEV_CHANGEMTU:
3362 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3363 		if (dev->mtu < IPV6_MIN_MTU) {
3364 			addrconf_ifdown(dev, dev != net->loopback_dev);
3365 			break;
3366 		}
3367 
3368 		if (idev) {
3369 			rt6_mtu_change(dev, dev->mtu);
3370 			idev->cnf.mtu6 = dev->mtu;
3371 			break;
3372 		}
3373 
3374 		/* allocate new idev */
3375 		idev = ipv6_add_dev(dev);
3376 		if (IS_ERR(idev))
3377 			break;
3378 
3379 		/* device is still not ready */
3380 		if (!(idev->if_flags & IF_READY))
3381 			break;
3382 
3383 		run_pending = 1;
3384 
3385 		/* fall through */
3386 
3387 	case NETDEV_UP:
3388 	case NETDEV_CHANGE:
3389 		if (dev->flags & IFF_SLAVE)
3390 			break;
3391 
3392 		if (idev && idev->cnf.disable_ipv6)
3393 			break;
3394 
3395 		if (event == NETDEV_UP) {
3396 			/* restore routes for permanent addresses */
3397 			addrconf_permanent_addr(dev);
3398 
3399 			if (!addrconf_link_ready(dev)) {
3400 				/* device is not ready yet. */
3401 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3402 					dev->name);
3403 				break;
3404 			}
3405 
3406 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3407 				idev = ipv6_add_dev(dev);
3408 
3409 			if (!IS_ERR_OR_NULL(idev)) {
3410 				idev->if_flags |= IF_READY;
3411 				run_pending = 1;
3412 			}
3413 		} else if (event == NETDEV_CHANGE) {
3414 			if (!addrconf_link_ready(dev)) {
3415 				/* device is still not ready. */
3416 				break;
3417 			}
3418 
3419 			if (idev) {
3420 				if (idev->if_flags & IF_READY) {
3421 					/* device is already configured -
3422 					 * but resend MLD reports, we might
3423 					 * have roamed and need to update
3424 					 * multicast snooping switches
3425 					 */
3426 					ipv6_mc_up(idev);
3427 					break;
3428 				}
3429 				idev->if_flags |= IF_READY;
3430 			}
3431 
3432 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3433 				dev->name);
3434 
3435 			run_pending = 1;
3436 		}
3437 
3438 		switch (dev->type) {
3439 #if IS_ENABLED(CONFIG_IPV6_SIT)
3440 		case ARPHRD_SIT:
3441 			addrconf_sit_config(dev);
3442 			break;
3443 #endif
3444 #if IS_ENABLED(CONFIG_NET_IPGRE)
3445 		case ARPHRD_IPGRE:
3446 			addrconf_gre_config(dev);
3447 			break;
3448 #endif
3449 		case ARPHRD_LOOPBACK:
3450 			init_loopback(dev);
3451 			break;
3452 
3453 		default:
3454 			addrconf_dev_config(dev);
3455 			break;
3456 		}
3457 
3458 		if (!IS_ERR_OR_NULL(idev)) {
3459 			if (run_pending)
3460 				addrconf_dad_run(idev);
3461 
3462 			/*
3463 			 * If the MTU changed during the interface down,
3464 			 * when the interface up, the changed MTU must be
3465 			 * reflected in the idev as well as routers.
3466 			 */
3467 			if (idev->cnf.mtu6 != dev->mtu &&
3468 			    dev->mtu >= IPV6_MIN_MTU) {
3469 				rt6_mtu_change(dev, dev->mtu);
3470 				idev->cnf.mtu6 = dev->mtu;
3471 			}
3472 			idev->tstamp = jiffies;
3473 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3474 
3475 			/*
3476 			 * If the changed mtu during down is lower than
3477 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3478 			 */
3479 			if (dev->mtu < IPV6_MIN_MTU)
3480 				addrconf_ifdown(dev, dev != net->loopback_dev);
3481 		}
3482 		break;
3483 
3484 	case NETDEV_DOWN:
3485 	case NETDEV_UNREGISTER:
3486 		/*
3487 		 *	Remove all addresses from this interface.
3488 		 */
3489 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3490 		break;
3491 
3492 	case NETDEV_CHANGENAME:
3493 		if (idev) {
3494 			snmp6_unregister_dev(idev);
3495 			addrconf_sysctl_unregister(idev);
3496 			err = addrconf_sysctl_register(idev);
3497 			if (err)
3498 				return notifier_from_errno(err);
3499 			err = snmp6_register_dev(idev);
3500 			if (err) {
3501 				addrconf_sysctl_unregister(idev);
3502 				return notifier_from_errno(err);
3503 			}
3504 		}
3505 		break;
3506 
3507 	case NETDEV_PRE_TYPE_CHANGE:
3508 	case NETDEV_POST_TYPE_CHANGE:
3509 		if (idev)
3510 			addrconf_type_change(dev, event);
3511 		break;
3512 
3513 	case NETDEV_CHANGEUPPER:
3514 		info = ptr;
3515 
3516 		/* flush all routes if dev is linked to or unlinked from
3517 		 * an L3 master device (e.g., VRF)
3518 		 */
3519 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3520 			addrconf_ifdown(dev, 0);
3521 	}
3522 
3523 	return NOTIFY_OK;
3524 }
3525 
3526 /*
3527  *	addrconf module should be notified of a device going up
3528  */
3529 static struct notifier_block ipv6_dev_notf = {
3530 	.notifier_call = addrconf_notify,
3531 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3532 };
3533 
3534 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3535 {
3536 	struct inet6_dev *idev;
3537 	ASSERT_RTNL();
3538 
3539 	idev = __in6_dev_get(dev);
3540 
3541 	if (event == NETDEV_POST_TYPE_CHANGE)
3542 		ipv6_mc_remap(idev);
3543 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3544 		ipv6_mc_unmap(idev);
3545 }
3546 
3547 static bool addr_is_local(const struct in6_addr *addr)
3548 {
3549 	return ipv6_addr_type(addr) &
3550 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3551 }
3552 
3553 static int addrconf_ifdown(struct net_device *dev, int how)
3554 {
3555 	struct net *net = dev_net(dev);
3556 	struct inet6_dev *idev;
3557 	struct inet6_ifaddr *ifa, *tmp;
3558 	int _keep_addr;
3559 	bool keep_addr;
3560 	int state, i;
3561 
3562 	ASSERT_RTNL();
3563 
3564 	rt6_ifdown(net, dev);
3565 	neigh_ifdown(&nd_tbl, dev);
3566 
3567 	idev = __in6_dev_get(dev);
3568 	if (!idev)
3569 		return -ENODEV;
3570 
3571 	/*
3572 	 * Step 1: remove reference to ipv6 device from parent device.
3573 	 *	   Do not dev_put!
3574 	 */
3575 	if (how) {
3576 		idev->dead = 1;
3577 
3578 		/* protected by rtnl_lock */
3579 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3580 
3581 		/* Step 1.5: remove snmp6 entry */
3582 		snmp6_unregister_dev(idev);
3583 
3584 	}
3585 
3586 	/* aggregate the system setting and interface setting */
3587 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3588 	if (!_keep_addr)
3589 		_keep_addr = idev->cnf.keep_addr_on_down;
3590 
3591 	/* combine the user config with event to determine if permanent
3592 	 * addresses are to be removed from address hash table
3593 	 */
3594 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3595 
3596 	/* Step 2: clear hash table */
3597 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3598 		struct hlist_head *h = &inet6_addr_lst[i];
3599 
3600 		spin_lock_bh(&addrconf_hash_lock);
3601 restart:
3602 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3603 			if (ifa->idev == idev) {
3604 				addrconf_del_dad_work(ifa);
3605 				/* combined flag + permanent flag decide if
3606 				 * address is retained on a down event
3607 				 */
3608 				if (!keep_addr ||
3609 				    !(ifa->flags & IFA_F_PERMANENT) ||
3610 				    addr_is_local(&ifa->addr)) {
3611 					hlist_del_init_rcu(&ifa->addr_lst);
3612 					goto restart;
3613 				}
3614 			}
3615 		}
3616 		spin_unlock_bh(&addrconf_hash_lock);
3617 	}
3618 
3619 	write_lock_bh(&idev->lock);
3620 
3621 	addrconf_del_rs_timer(idev);
3622 
3623 	/* Step 2: clear flags for stateless addrconf */
3624 	if (!how)
3625 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3626 
3627 	/* Step 3: clear tempaddr list */
3628 	while (!list_empty(&idev->tempaddr_list)) {
3629 		ifa = list_first_entry(&idev->tempaddr_list,
3630 				       struct inet6_ifaddr, tmp_list);
3631 		list_del(&ifa->tmp_list);
3632 		write_unlock_bh(&idev->lock);
3633 		spin_lock_bh(&ifa->lock);
3634 
3635 		if (ifa->ifpub) {
3636 			in6_ifa_put(ifa->ifpub);
3637 			ifa->ifpub = NULL;
3638 		}
3639 		spin_unlock_bh(&ifa->lock);
3640 		in6_ifa_put(ifa);
3641 		write_lock_bh(&idev->lock);
3642 	}
3643 
3644 	/* re-combine the user config with event to determine if permanent
3645 	 * addresses are to be removed from the interface list
3646 	 */
3647 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3648 
3649 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3650 		struct rt6_info *rt = NULL;
3651 		bool keep;
3652 
3653 		addrconf_del_dad_work(ifa);
3654 
3655 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3656 			!addr_is_local(&ifa->addr);
3657 
3658 		write_unlock_bh(&idev->lock);
3659 		spin_lock_bh(&ifa->lock);
3660 
3661 		if (keep) {
3662 			/* set state to skip the notifier below */
3663 			state = INET6_IFADDR_STATE_DEAD;
3664 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3665 			if (!(ifa->flags & IFA_F_NODAD))
3666 				ifa->flags |= IFA_F_TENTATIVE;
3667 
3668 			rt = ifa->rt;
3669 			ifa->rt = NULL;
3670 		} else {
3671 			state = ifa->state;
3672 			ifa->state = INET6_IFADDR_STATE_DEAD;
3673 		}
3674 
3675 		spin_unlock_bh(&ifa->lock);
3676 
3677 		if (rt)
3678 			ip6_del_rt(rt);
3679 
3680 		if (state != INET6_IFADDR_STATE_DEAD) {
3681 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3682 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3683 		} else {
3684 			if (idev->cnf.forwarding)
3685 				addrconf_leave_anycast(ifa);
3686 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3687 		}
3688 
3689 		write_lock_bh(&idev->lock);
3690 		if (!keep) {
3691 			list_del_rcu(&ifa->if_list);
3692 			in6_ifa_put(ifa);
3693 		}
3694 	}
3695 
3696 	write_unlock_bh(&idev->lock);
3697 
3698 	/* Step 5: Discard anycast and multicast list */
3699 	if (how) {
3700 		ipv6_ac_destroy_dev(idev);
3701 		ipv6_mc_destroy_dev(idev);
3702 	} else {
3703 		ipv6_mc_down(idev);
3704 	}
3705 
3706 	idev->tstamp = jiffies;
3707 
3708 	/* Last: Shot the device (if unregistered) */
3709 	if (how) {
3710 		addrconf_sysctl_unregister(idev);
3711 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3712 		neigh_ifdown(&nd_tbl, dev);
3713 		in6_dev_put(idev);
3714 	}
3715 	return 0;
3716 }
3717 
3718 static void addrconf_rs_timer(unsigned long data)
3719 {
3720 	struct inet6_dev *idev = (struct inet6_dev *)data;
3721 	struct net_device *dev = idev->dev;
3722 	struct in6_addr lladdr;
3723 
3724 	write_lock(&idev->lock);
3725 	if (idev->dead || !(idev->if_flags & IF_READY))
3726 		goto out;
3727 
3728 	if (!ipv6_accept_ra(idev))
3729 		goto out;
3730 
3731 	/* Announcement received after solicitation was sent */
3732 	if (idev->if_flags & IF_RA_RCVD)
3733 		goto out;
3734 
3735 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3736 		write_unlock(&idev->lock);
3737 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3738 			ndisc_send_rs(dev, &lladdr,
3739 				      &in6addr_linklocal_allrouters);
3740 		else
3741 			goto put;
3742 
3743 		write_lock(&idev->lock);
3744 		idev->rs_interval = rfc3315_s14_backoff_update(
3745 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3746 		/* The wait after the last probe can be shorter */
3747 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3748 					     idev->cnf.rtr_solicits) ?
3749 				      idev->cnf.rtr_solicit_delay :
3750 				      idev->rs_interval);
3751 	} else {
3752 		/*
3753 		 * Note: we do not support deprecated "all on-link"
3754 		 * assumption any longer.
3755 		 */
3756 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3757 	}
3758 
3759 out:
3760 	write_unlock(&idev->lock);
3761 put:
3762 	in6_dev_put(idev);
3763 }
3764 
3765 /*
3766  *	Duplicate Address Detection
3767  */
3768 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3769 {
3770 	unsigned long rand_num;
3771 	struct inet6_dev *idev = ifp->idev;
3772 	u64 nonce;
3773 
3774 	if (ifp->flags & IFA_F_OPTIMISTIC)
3775 		rand_num = 0;
3776 	else
3777 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3778 
3779 	nonce = 0;
3780 	if (idev->cnf.enhanced_dad ||
3781 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3782 		do
3783 			get_random_bytes(&nonce, 6);
3784 		while (nonce == 0);
3785 	}
3786 	ifp->dad_nonce = nonce;
3787 	ifp->dad_probes = idev->cnf.dad_transmits;
3788 	addrconf_mod_dad_work(ifp, rand_num);
3789 }
3790 
3791 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3792 {
3793 	struct inet6_dev *idev = ifp->idev;
3794 	struct net_device *dev = idev->dev;
3795 	bool bump_id, notify = false;
3796 
3797 	addrconf_join_solict(dev, &ifp->addr);
3798 
3799 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3800 
3801 	read_lock_bh(&idev->lock);
3802 	spin_lock(&ifp->lock);
3803 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3804 		goto out;
3805 
3806 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3807 	    (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 &&
3808 	     idev->cnf.accept_dad < 1) ||
3809 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3810 	    ifp->flags & IFA_F_NODAD) {
3811 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3812 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3813 		spin_unlock(&ifp->lock);
3814 		read_unlock_bh(&idev->lock);
3815 
3816 		addrconf_dad_completed(ifp, bump_id);
3817 		return;
3818 	}
3819 
3820 	if (!(idev->if_flags & IF_READY)) {
3821 		spin_unlock(&ifp->lock);
3822 		read_unlock_bh(&idev->lock);
3823 		/*
3824 		 * If the device is not ready:
3825 		 * - keep it tentative if it is a permanent address.
3826 		 * - otherwise, kill it.
3827 		 */
3828 		in6_ifa_hold(ifp);
3829 		addrconf_dad_stop(ifp, 0);
3830 		return;
3831 	}
3832 
3833 	/*
3834 	 * Optimistic nodes can start receiving
3835 	 * Frames right away
3836 	 */
3837 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3838 		ip6_ins_rt(ifp->rt);
3839 		if (ipv6_use_optimistic_addr(dev_net(dev), idev)) {
3840 			/* Because optimistic nodes can use this address,
3841 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3842 			 */
3843 			notify = true;
3844 		}
3845 	}
3846 
3847 	addrconf_dad_kick(ifp);
3848 out:
3849 	spin_unlock(&ifp->lock);
3850 	read_unlock_bh(&idev->lock);
3851 	if (notify)
3852 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3853 }
3854 
3855 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3856 {
3857 	bool begin_dad = false;
3858 
3859 	spin_lock_bh(&ifp->lock);
3860 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3861 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3862 		begin_dad = true;
3863 	}
3864 	spin_unlock_bh(&ifp->lock);
3865 
3866 	if (begin_dad)
3867 		addrconf_mod_dad_work(ifp, 0);
3868 }
3869 
3870 static void addrconf_dad_work(struct work_struct *w)
3871 {
3872 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3873 						struct inet6_ifaddr,
3874 						dad_work);
3875 	struct inet6_dev *idev = ifp->idev;
3876 	bool bump_id, disable_ipv6 = false;
3877 	struct in6_addr mcaddr;
3878 
3879 	enum {
3880 		DAD_PROCESS,
3881 		DAD_BEGIN,
3882 		DAD_ABORT,
3883 	} action = DAD_PROCESS;
3884 
3885 	rtnl_lock();
3886 
3887 	spin_lock_bh(&ifp->lock);
3888 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3889 		action = DAD_BEGIN;
3890 		ifp->state = INET6_IFADDR_STATE_DAD;
3891 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3892 		action = DAD_ABORT;
3893 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3894 
3895 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3896 		     idev->cnf.accept_dad > 1) &&
3897 		    !idev->cnf.disable_ipv6 &&
3898 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3899 			struct in6_addr addr;
3900 
3901 			addr.s6_addr32[0] = htonl(0xfe800000);
3902 			addr.s6_addr32[1] = 0;
3903 
3904 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3905 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3906 				/* DAD failed for link-local based on MAC */
3907 				idev->cnf.disable_ipv6 = 1;
3908 
3909 				pr_info("%s: IPv6 being disabled!\n",
3910 					ifp->idev->dev->name);
3911 				disable_ipv6 = true;
3912 			}
3913 		}
3914 	}
3915 	spin_unlock_bh(&ifp->lock);
3916 
3917 	if (action == DAD_BEGIN) {
3918 		addrconf_dad_begin(ifp);
3919 		goto out;
3920 	} else if (action == DAD_ABORT) {
3921 		in6_ifa_hold(ifp);
3922 		addrconf_dad_stop(ifp, 1);
3923 		if (disable_ipv6)
3924 			addrconf_ifdown(idev->dev, 0);
3925 		goto out;
3926 	}
3927 
3928 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3929 		goto out;
3930 
3931 	write_lock_bh(&idev->lock);
3932 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3933 		write_unlock_bh(&idev->lock);
3934 		goto out;
3935 	}
3936 
3937 	spin_lock(&ifp->lock);
3938 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3939 		spin_unlock(&ifp->lock);
3940 		write_unlock_bh(&idev->lock);
3941 		goto out;
3942 	}
3943 
3944 	if (ifp->dad_probes == 0) {
3945 		/*
3946 		 * DAD was successful
3947 		 */
3948 
3949 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3950 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3951 		spin_unlock(&ifp->lock);
3952 		write_unlock_bh(&idev->lock);
3953 
3954 		addrconf_dad_completed(ifp, bump_id);
3955 
3956 		goto out;
3957 	}
3958 
3959 	ifp->dad_probes--;
3960 	addrconf_mod_dad_work(ifp,
3961 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3962 	spin_unlock(&ifp->lock);
3963 	write_unlock_bh(&idev->lock);
3964 
3965 	/* send a neighbour solicitation for our addr */
3966 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3967 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
3968 		      ifp->dad_nonce);
3969 out:
3970 	in6_ifa_put(ifp);
3971 	rtnl_unlock();
3972 }
3973 
3974 /* ifp->idev must be at least read locked */
3975 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3976 {
3977 	struct inet6_ifaddr *ifpiter;
3978 	struct inet6_dev *idev = ifp->idev;
3979 
3980 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3981 		if (ifpiter->scope > IFA_LINK)
3982 			break;
3983 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
3984 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
3985 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
3986 		    IFA_F_PERMANENT)
3987 			return false;
3988 	}
3989 	return true;
3990 }
3991 
3992 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
3993 {
3994 	struct net_device *dev = ifp->idev->dev;
3995 	struct in6_addr lladdr;
3996 	bool send_rs, send_mld;
3997 
3998 	addrconf_del_dad_work(ifp);
3999 
4000 	/*
4001 	 *	Configure the address for reception. Now it is valid.
4002 	 */
4003 
4004 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4005 
4006 	/* If added prefix is link local and we are prepared to process
4007 	   router advertisements, start sending router solicitations.
4008 	 */
4009 
4010 	read_lock_bh(&ifp->idev->lock);
4011 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4012 	send_rs = send_mld &&
4013 		  ipv6_accept_ra(ifp->idev) &&
4014 		  ifp->idev->cnf.rtr_solicits != 0 &&
4015 		  (dev->flags&IFF_LOOPBACK) == 0;
4016 	read_unlock_bh(&ifp->idev->lock);
4017 
4018 	/* While dad is in progress mld report's source address is in6_addrany.
4019 	 * Resend with proper ll now.
4020 	 */
4021 	if (send_mld)
4022 		ipv6_mc_dad_complete(ifp->idev);
4023 
4024 	if (send_rs) {
4025 		/*
4026 		 *	If a host as already performed a random delay
4027 		 *	[...] as part of DAD [...] there is no need
4028 		 *	to delay again before sending the first RS
4029 		 */
4030 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4031 			return;
4032 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4033 
4034 		write_lock_bh(&ifp->idev->lock);
4035 		spin_lock(&ifp->lock);
4036 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4037 			ifp->idev->cnf.rtr_solicit_interval);
4038 		ifp->idev->rs_probes = 1;
4039 		ifp->idev->if_flags |= IF_RS_SENT;
4040 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4041 		spin_unlock(&ifp->lock);
4042 		write_unlock_bh(&ifp->idev->lock);
4043 	}
4044 
4045 	if (bump_id)
4046 		rt_genid_bump_ipv6(dev_net(dev));
4047 
4048 	/* Make sure that a new temporary address will be created
4049 	 * before this temporary address becomes deprecated.
4050 	 */
4051 	if (ifp->flags & IFA_F_TEMPORARY)
4052 		addrconf_verify_rtnl();
4053 }
4054 
4055 static void addrconf_dad_run(struct inet6_dev *idev)
4056 {
4057 	struct inet6_ifaddr *ifp;
4058 
4059 	read_lock_bh(&idev->lock);
4060 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4061 		spin_lock(&ifp->lock);
4062 		if (ifp->flags & IFA_F_TENTATIVE &&
4063 		    ifp->state == INET6_IFADDR_STATE_DAD)
4064 			addrconf_dad_kick(ifp);
4065 		spin_unlock(&ifp->lock);
4066 	}
4067 	read_unlock_bh(&idev->lock);
4068 }
4069 
4070 #ifdef CONFIG_PROC_FS
4071 struct if6_iter_state {
4072 	struct seq_net_private p;
4073 	int bucket;
4074 	int offset;
4075 };
4076 
4077 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4078 {
4079 	struct inet6_ifaddr *ifa = NULL;
4080 	struct if6_iter_state *state = seq->private;
4081 	struct net *net = seq_file_net(seq);
4082 	int p = 0;
4083 
4084 	/* initial bucket if pos is 0 */
4085 	if (pos == 0) {
4086 		state->bucket = 0;
4087 		state->offset = 0;
4088 	}
4089 
4090 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4091 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4092 					 addr_lst) {
4093 			if (!net_eq(dev_net(ifa->idev->dev), net))
4094 				continue;
4095 			/* sync with offset */
4096 			if (p < state->offset) {
4097 				p++;
4098 				continue;
4099 			}
4100 			state->offset++;
4101 			return ifa;
4102 		}
4103 
4104 		/* prepare for next bucket */
4105 		state->offset = 0;
4106 		p = 0;
4107 	}
4108 	return NULL;
4109 }
4110 
4111 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4112 					 struct inet6_ifaddr *ifa)
4113 {
4114 	struct if6_iter_state *state = seq->private;
4115 	struct net *net = seq_file_net(seq);
4116 
4117 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4118 		if (!net_eq(dev_net(ifa->idev->dev), net))
4119 			continue;
4120 		state->offset++;
4121 		return ifa;
4122 	}
4123 
4124 	while (++state->bucket < IN6_ADDR_HSIZE) {
4125 		state->offset = 0;
4126 		hlist_for_each_entry_rcu_bh(ifa,
4127 				     &inet6_addr_lst[state->bucket], addr_lst) {
4128 			if (!net_eq(dev_net(ifa->idev->dev), net))
4129 				continue;
4130 			state->offset++;
4131 			return ifa;
4132 		}
4133 	}
4134 
4135 	return NULL;
4136 }
4137 
4138 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4139 	__acquires(rcu_bh)
4140 {
4141 	rcu_read_lock_bh();
4142 	return if6_get_first(seq, *pos);
4143 }
4144 
4145 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4146 {
4147 	struct inet6_ifaddr *ifa;
4148 
4149 	ifa = if6_get_next(seq, v);
4150 	++*pos;
4151 	return ifa;
4152 }
4153 
4154 static void if6_seq_stop(struct seq_file *seq, void *v)
4155 	__releases(rcu_bh)
4156 {
4157 	rcu_read_unlock_bh();
4158 }
4159 
4160 static int if6_seq_show(struct seq_file *seq, void *v)
4161 {
4162 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4163 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4164 		   &ifp->addr,
4165 		   ifp->idev->dev->ifindex,
4166 		   ifp->prefix_len,
4167 		   ifp->scope,
4168 		   (u8) ifp->flags,
4169 		   ifp->idev->dev->name);
4170 	return 0;
4171 }
4172 
4173 static const struct seq_operations if6_seq_ops = {
4174 	.start	= if6_seq_start,
4175 	.next	= if6_seq_next,
4176 	.show	= if6_seq_show,
4177 	.stop	= if6_seq_stop,
4178 };
4179 
4180 static int if6_seq_open(struct inode *inode, struct file *file)
4181 {
4182 	return seq_open_net(inode, file, &if6_seq_ops,
4183 			    sizeof(struct if6_iter_state));
4184 }
4185 
4186 static const struct file_operations if6_fops = {
4187 	.owner		= THIS_MODULE,
4188 	.open		= if6_seq_open,
4189 	.read		= seq_read,
4190 	.llseek		= seq_lseek,
4191 	.release	= seq_release_net,
4192 };
4193 
4194 static int __net_init if6_proc_net_init(struct net *net)
4195 {
4196 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4197 		return -ENOMEM;
4198 	return 0;
4199 }
4200 
4201 static void __net_exit if6_proc_net_exit(struct net *net)
4202 {
4203 	remove_proc_entry("if_inet6", net->proc_net);
4204 }
4205 
4206 static struct pernet_operations if6_proc_net_ops = {
4207 	.init = if6_proc_net_init,
4208 	.exit = if6_proc_net_exit,
4209 };
4210 
4211 int __init if6_proc_init(void)
4212 {
4213 	return register_pernet_subsys(&if6_proc_net_ops);
4214 }
4215 
4216 void if6_proc_exit(void)
4217 {
4218 	unregister_pernet_subsys(&if6_proc_net_ops);
4219 }
4220 #endif	/* CONFIG_PROC_FS */
4221 
4222 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4223 /* Check if address is a home address configured on any interface. */
4224 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4225 {
4226 	int ret = 0;
4227 	struct inet6_ifaddr *ifp = NULL;
4228 	unsigned int hash = inet6_addr_hash(addr);
4229 
4230 	rcu_read_lock_bh();
4231 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4232 		if (!net_eq(dev_net(ifp->idev->dev), net))
4233 			continue;
4234 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4235 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4236 			ret = 1;
4237 			break;
4238 		}
4239 	}
4240 	rcu_read_unlock_bh();
4241 	return ret;
4242 }
4243 #endif
4244 
4245 /*
4246  *	Periodic address status verification
4247  */
4248 
4249 static void addrconf_verify_rtnl(void)
4250 {
4251 	unsigned long now, next, next_sec, next_sched;
4252 	struct inet6_ifaddr *ifp;
4253 	int i;
4254 
4255 	ASSERT_RTNL();
4256 
4257 	rcu_read_lock_bh();
4258 	now = jiffies;
4259 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4260 
4261 	cancel_delayed_work(&addr_chk_work);
4262 
4263 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4264 restart:
4265 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4266 			unsigned long age;
4267 
4268 			/* When setting preferred_lft to a value not zero or
4269 			 * infinity, while valid_lft is infinity
4270 			 * IFA_F_PERMANENT has a non-infinity life time.
4271 			 */
4272 			if ((ifp->flags & IFA_F_PERMANENT) &&
4273 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4274 				continue;
4275 
4276 			spin_lock(&ifp->lock);
4277 			/* We try to batch several events at once. */
4278 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4279 
4280 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4281 			    age >= ifp->valid_lft) {
4282 				spin_unlock(&ifp->lock);
4283 				in6_ifa_hold(ifp);
4284 				ipv6_del_addr(ifp);
4285 				goto restart;
4286 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4287 				spin_unlock(&ifp->lock);
4288 				continue;
4289 			} else if (age >= ifp->prefered_lft) {
4290 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4291 				int deprecate = 0;
4292 
4293 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4294 					deprecate = 1;
4295 					ifp->flags |= IFA_F_DEPRECATED;
4296 				}
4297 
4298 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4299 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4300 					next = ifp->tstamp + ifp->valid_lft * HZ;
4301 
4302 				spin_unlock(&ifp->lock);
4303 
4304 				if (deprecate) {
4305 					in6_ifa_hold(ifp);
4306 
4307 					ipv6_ifa_notify(0, ifp);
4308 					in6_ifa_put(ifp);
4309 					goto restart;
4310 				}
4311 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4312 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4313 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4314 					ifp->idev->cnf.dad_transmits *
4315 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4316 
4317 				if (age >= ifp->prefered_lft - regen_advance) {
4318 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4319 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4320 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4321 					if (!ifp->regen_count && ifpub) {
4322 						ifp->regen_count++;
4323 						in6_ifa_hold(ifp);
4324 						in6_ifa_hold(ifpub);
4325 						spin_unlock(&ifp->lock);
4326 
4327 						spin_lock(&ifpub->lock);
4328 						ifpub->regen_count = 0;
4329 						spin_unlock(&ifpub->lock);
4330 						ipv6_create_tempaddr(ifpub, ifp);
4331 						in6_ifa_put(ifpub);
4332 						in6_ifa_put(ifp);
4333 						goto restart;
4334 					}
4335 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4336 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4337 				spin_unlock(&ifp->lock);
4338 			} else {
4339 				/* ifp->prefered_lft <= ifp->valid_lft */
4340 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4341 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4342 				spin_unlock(&ifp->lock);
4343 			}
4344 		}
4345 	}
4346 
4347 	next_sec = round_jiffies_up(next);
4348 	next_sched = next;
4349 
4350 	/* If rounded timeout is accurate enough, accept it. */
4351 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4352 		next_sched = next_sec;
4353 
4354 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4355 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4356 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4357 
4358 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4359 	      now, next, next_sec, next_sched);
4360 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4361 	rcu_read_unlock_bh();
4362 }
4363 
4364 static void addrconf_verify_work(struct work_struct *w)
4365 {
4366 	rtnl_lock();
4367 	addrconf_verify_rtnl();
4368 	rtnl_unlock();
4369 }
4370 
4371 static void addrconf_verify(void)
4372 {
4373 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4374 }
4375 
4376 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4377 				     struct in6_addr **peer_pfx)
4378 {
4379 	struct in6_addr *pfx = NULL;
4380 
4381 	*peer_pfx = NULL;
4382 
4383 	if (addr)
4384 		pfx = nla_data(addr);
4385 
4386 	if (local) {
4387 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4388 			*peer_pfx = pfx;
4389 		pfx = nla_data(local);
4390 	}
4391 
4392 	return pfx;
4393 }
4394 
4395 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4396 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4397 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4398 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4399 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4400 };
4401 
4402 static int
4403 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4404 		  struct netlink_ext_ack *extack)
4405 {
4406 	struct net *net = sock_net(skb->sk);
4407 	struct ifaddrmsg *ifm;
4408 	struct nlattr *tb[IFA_MAX+1];
4409 	struct in6_addr *pfx, *peer_pfx;
4410 	u32 ifa_flags;
4411 	int err;
4412 
4413 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4414 			  extack);
4415 	if (err < 0)
4416 		return err;
4417 
4418 	ifm = nlmsg_data(nlh);
4419 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4420 	if (!pfx)
4421 		return -EINVAL;
4422 
4423 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4424 
4425 	/* We ignore other flags so far. */
4426 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4427 
4428 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4429 			      ifm->ifa_prefixlen);
4430 }
4431 
4432 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4433 			     u32 prefered_lft, u32 valid_lft)
4434 {
4435 	u32 flags;
4436 	clock_t expires;
4437 	unsigned long timeout;
4438 	bool was_managetempaddr;
4439 	bool had_prefixroute;
4440 
4441 	ASSERT_RTNL();
4442 
4443 	if (!valid_lft || (prefered_lft > valid_lft))
4444 		return -EINVAL;
4445 
4446 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4447 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4448 		return -EINVAL;
4449 
4450 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4451 	if (addrconf_finite_timeout(timeout)) {
4452 		expires = jiffies_to_clock_t(timeout * HZ);
4453 		valid_lft = timeout;
4454 		flags = RTF_EXPIRES;
4455 	} else {
4456 		expires = 0;
4457 		flags = 0;
4458 		ifa_flags |= IFA_F_PERMANENT;
4459 	}
4460 
4461 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4462 	if (addrconf_finite_timeout(timeout)) {
4463 		if (timeout == 0)
4464 			ifa_flags |= IFA_F_DEPRECATED;
4465 		prefered_lft = timeout;
4466 	}
4467 
4468 	spin_lock_bh(&ifp->lock);
4469 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4470 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4471 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4472 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4473 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4474 			IFA_F_NOPREFIXROUTE);
4475 	ifp->flags |= ifa_flags;
4476 	ifp->tstamp = jiffies;
4477 	ifp->valid_lft = valid_lft;
4478 	ifp->prefered_lft = prefered_lft;
4479 
4480 	spin_unlock_bh(&ifp->lock);
4481 	if (!(ifp->flags&IFA_F_TENTATIVE))
4482 		ipv6_ifa_notify(0, ifp);
4483 
4484 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4485 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4486 				      expires, flags);
4487 	} else if (had_prefixroute) {
4488 		enum cleanup_prefix_rt_t action;
4489 		unsigned long rt_expires;
4490 
4491 		write_lock_bh(&ifp->idev->lock);
4492 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4493 		write_unlock_bh(&ifp->idev->lock);
4494 
4495 		if (action != CLEANUP_PREFIX_RT_NOP) {
4496 			cleanup_prefix_route(ifp, rt_expires,
4497 				action == CLEANUP_PREFIX_RT_DEL);
4498 		}
4499 	}
4500 
4501 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4502 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4503 			valid_lft = prefered_lft = 0;
4504 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4505 				 !was_managetempaddr, jiffies);
4506 	}
4507 
4508 	addrconf_verify_rtnl();
4509 
4510 	return 0;
4511 }
4512 
4513 static int
4514 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4515 		  struct netlink_ext_ack *extack)
4516 {
4517 	struct net *net = sock_net(skb->sk);
4518 	struct ifaddrmsg *ifm;
4519 	struct nlattr *tb[IFA_MAX+1];
4520 	struct in6_addr *pfx, *peer_pfx;
4521 	struct inet6_ifaddr *ifa;
4522 	struct net_device *dev;
4523 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4524 	u32 ifa_flags;
4525 	int err;
4526 
4527 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4528 			  extack);
4529 	if (err < 0)
4530 		return err;
4531 
4532 	ifm = nlmsg_data(nlh);
4533 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4534 	if (!pfx)
4535 		return -EINVAL;
4536 
4537 	if (tb[IFA_CACHEINFO]) {
4538 		struct ifa_cacheinfo *ci;
4539 
4540 		ci = nla_data(tb[IFA_CACHEINFO]);
4541 		valid_lft = ci->ifa_valid;
4542 		preferred_lft = ci->ifa_prefered;
4543 	} else {
4544 		preferred_lft = INFINITY_LIFE_TIME;
4545 		valid_lft = INFINITY_LIFE_TIME;
4546 	}
4547 
4548 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4549 	if (!dev)
4550 		return -ENODEV;
4551 
4552 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4553 
4554 	/* We ignore other flags so far. */
4555 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4556 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4557 
4558 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4559 	if (!ifa) {
4560 		/*
4561 		 * It would be best to check for !NLM_F_CREATE here but
4562 		 * userspace already relies on not having to provide this.
4563 		 */
4564 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4565 				      ifm->ifa_prefixlen, ifa_flags,
4566 				      preferred_lft, valid_lft);
4567 	}
4568 
4569 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4570 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4571 		err = -EEXIST;
4572 	else
4573 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4574 
4575 	in6_ifa_put(ifa);
4576 
4577 	return err;
4578 }
4579 
4580 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4581 			  u8 scope, int ifindex)
4582 {
4583 	struct ifaddrmsg *ifm;
4584 
4585 	ifm = nlmsg_data(nlh);
4586 	ifm->ifa_family = AF_INET6;
4587 	ifm->ifa_prefixlen = prefixlen;
4588 	ifm->ifa_flags = flags;
4589 	ifm->ifa_scope = scope;
4590 	ifm->ifa_index = ifindex;
4591 }
4592 
4593 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4594 			 unsigned long tstamp, u32 preferred, u32 valid)
4595 {
4596 	struct ifa_cacheinfo ci;
4597 
4598 	ci.cstamp = cstamp_delta(cstamp);
4599 	ci.tstamp = cstamp_delta(tstamp);
4600 	ci.ifa_prefered = preferred;
4601 	ci.ifa_valid = valid;
4602 
4603 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4604 }
4605 
4606 static inline int rt_scope(int ifa_scope)
4607 {
4608 	if (ifa_scope & IFA_HOST)
4609 		return RT_SCOPE_HOST;
4610 	else if (ifa_scope & IFA_LINK)
4611 		return RT_SCOPE_LINK;
4612 	else if (ifa_scope & IFA_SITE)
4613 		return RT_SCOPE_SITE;
4614 	else
4615 		return RT_SCOPE_UNIVERSE;
4616 }
4617 
4618 static inline int inet6_ifaddr_msgsize(void)
4619 {
4620 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4621 	       + nla_total_size(16) /* IFA_LOCAL */
4622 	       + nla_total_size(16) /* IFA_ADDRESS */
4623 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4624 	       + nla_total_size(4)  /* IFA_FLAGS */;
4625 }
4626 
4627 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4628 			     u32 portid, u32 seq, int event, unsigned int flags)
4629 {
4630 	struct nlmsghdr  *nlh;
4631 	u32 preferred, valid;
4632 
4633 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4634 	if (!nlh)
4635 		return -EMSGSIZE;
4636 
4637 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4638 		      ifa->idev->dev->ifindex);
4639 
4640 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4641 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4642 		preferred = ifa->prefered_lft;
4643 		valid = ifa->valid_lft;
4644 		if (preferred != INFINITY_LIFE_TIME) {
4645 			long tval = (jiffies - ifa->tstamp)/HZ;
4646 			if (preferred > tval)
4647 				preferred -= tval;
4648 			else
4649 				preferred = 0;
4650 			if (valid != INFINITY_LIFE_TIME) {
4651 				if (valid > tval)
4652 					valid -= tval;
4653 				else
4654 					valid = 0;
4655 			}
4656 		}
4657 	} else {
4658 		preferred = INFINITY_LIFE_TIME;
4659 		valid = INFINITY_LIFE_TIME;
4660 	}
4661 
4662 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4663 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4664 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4665 			goto error;
4666 	} else
4667 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4668 			goto error;
4669 
4670 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4671 		goto error;
4672 
4673 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4674 		goto error;
4675 
4676 	nlmsg_end(skb, nlh);
4677 	return 0;
4678 
4679 error:
4680 	nlmsg_cancel(skb, nlh);
4681 	return -EMSGSIZE;
4682 }
4683 
4684 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4685 				u32 portid, u32 seq, int event, u16 flags)
4686 {
4687 	struct nlmsghdr  *nlh;
4688 	u8 scope = RT_SCOPE_UNIVERSE;
4689 	int ifindex = ifmca->idev->dev->ifindex;
4690 
4691 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4692 		scope = RT_SCOPE_SITE;
4693 
4694 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4695 	if (!nlh)
4696 		return -EMSGSIZE;
4697 
4698 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4699 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4700 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4701 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4702 		nlmsg_cancel(skb, nlh);
4703 		return -EMSGSIZE;
4704 	}
4705 
4706 	nlmsg_end(skb, nlh);
4707 	return 0;
4708 }
4709 
4710 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4711 				u32 portid, u32 seq, int event, unsigned int flags)
4712 {
4713 	struct nlmsghdr  *nlh;
4714 	u8 scope = RT_SCOPE_UNIVERSE;
4715 	int ifindex = ifaca->aca_idev->dev->ifindex;
4716 
4717 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4718 		scope = RT_SCOPE_SITE;
4719 
4720 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4721 	if (!nlh)
4722 		return -EMSGSIZE;
4723 
4724 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4725 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4726 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4727 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4728 		nlmsg_cancel(skb, nlh);
4729 		return -EMSGSIZE;
4730 	}
4731 
4732 	nlmsg_end(skb, nlh);
4733 	return 0;
4734 }
4735 
4736 enum addr_type_t {
4737 	UNICAST_ADDR,
4738 	MULTICAST_ADDR,
4739 	ANYCAST_ADDR,
4740 };
4741 
4742 /* called with rcu_read_lock() */
4743 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4744 			  struct netlink_callback *cb, enum addr_type_t type,
4745 			  int s_ip_idx, int *p_ip_idx)
4746 {
4747 	struct ifmcaddr6 *ifmca;
4748 	struct ifacaddr6 *ifaca;
4749 	int err = 1;
4750 	int ip_idx = *p_ip_idx;
4751 
4752 	read_lock_bh(&idev->lock);
4753 	switch (type) {
4754 	case UNICAST_ADDR: {
4755 		struct inet6_ifaddr *ifa;
4756 
4757 		/* unicast address incl. temp addr */
4758 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4759 			if (++ip_idx < s_ip_idx)
4760 				continue;
4761 			err = inet6_fill_ifaddr(skb, ifa,
4762 						NETLINK_CB(cb->skb).portid,
4763 						cb->nlh->nlmsg_seq,
4764 						RTM_NEWADDR,
4765 						NLM_F_MULTI);
4766 			if (err < 0)
4767 				break;
4768 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4769 		}
4770 		break;
4771 	}
4772 	case MULTICAST_ADDR:
4773 		/* multicast address */
4774 		for (ifmca = idev->mc_list; ifmca;
4775 		     ifmca = ifmca->next, ip_idx++) {
4776 			if (ip_idx < s_ip_idx)
4777 				continue;
4778 			err = inet6_fill_ifmcaddr(skb, ifmca,
4779 						  NETLINK_CB(cb->skb).portid,
4780 						  cb->nlh->nlmsg_seq,
4781 						  RTM_GETMULTICAST,
4782 						  NLM_F_MULTI);
4783 			if (err < 0)
4784 				break;
4785 		}
4786 		break;
4787 	case ANYCAST_ADDR:
4788 		/* anycast address */
4789 		for (ifaca = idev->ac_list; ifaca;
4790 		     ifaca = ifaca->aca_next, ip_idx++) {
4791 			if (ip_idx < s_ip_idx)
4792 				continue;
4793 			err = inet6_fill_ifacaddr(skb, ifaca,
4794 						  NETLINK_CB(cb->skb).portid,
4795 						  cb->nlh->nlmsg_seq,
4796 						  RTM_GETANYCAST,
4797 						  NLM_F_MULTI);
4798 			if (err < 0)
4799 				break;
4800 		}
4801 		break;
4802 	default:
4803 		break;
4804 	}
4805 	read_unlock_bh(&idev->lock);
4806 	*p_ip_idx = ip_idx;
4807 	return err;
4808 }
4809 
4810 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4811 			   enum addr_type_t type)
4812 {
4813 	struct net *net = sock_net(skb->sk);
4814 	int h, s_h;
4815 	int idx, ip_idx;
4816 	int s_idx, s_ip_idx;
4817 	struct net_device *dev;
4818 	struct inet6_dev *idev;
4819 	struct hlist_head *head;
4820 
4821 	s_h = cb->args[0];
4822 	s_idx = idx = cb->args[1];
4823 	s_ip_idx = ip_idx = cb->args[2];
4824 
4825 	rcu_read_lock();
4826 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4827 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4828 		idx = 0;
4829 		head = &net->dev_index_head[h];
4830 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4831 			if (idx < s_idx)
4832 				goto cont;
4833 			if (h > s_h || idx > s_idx)
4834 				s_ip_idx = 0;
4835 			ip_idx = 0;
4836 			idev = __in6_dev_get(dev);
4837 			if (!idev)
4838 				goto cont;
4839 
4840 			if (in6_dump_addrs(idev, skb, cb, type,
4841 					   s_ip_idx, &ip_idx) < 0)
4842 				goto done;
4843 cont:
4844 			idx++;
4845 		}
4846 	}
4847 done:
4848 	rcu_read_unlock();
4849 	cb->args[0] = h;
4850 	cb->args[1] = idx;
4851 	cb->args[2] = ip_idx;
4852 
4853 	return skb->len;
4854 }
4855 
4856 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4857 {
4858 	enum addr_type_t type = UNICAST_ADDR;
4859 
4860 	return inet6_dump_addr(skb, cb, type);
4861 }
4862 
4863 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4864 {
4865 	enum addr_type_t type = MULTICAST_ADDR;
4866 
4867 	return inet6_dump_addr(skb, cb, type);
4868 }
4869 
4870 
4871 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4872 {
4873 	enum addr_type_t type = ANYCAST_ADDR;
4874 
4875 	return inet6_dump_addr(skb, cb, type);
4876 }
4877 
4878 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4879 			     struct netlink_ext_ack *extack)
4880 {
4881 	struct net *net = sock_net(in_skb->sk);
4882 	struct ifaddrmsg *ifm;
4883 	struct nlattr *tb[IFA_MAX+1];
4884 	struct in6_addr *addr = NULL, *peer;
4885 	struct net_device *dev = NULL;
4886 	struct inet6_ifaddr *ifa;
4887 	struct sk_buff *skb;
4888 	int err;
4889 
4890 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4891 			  extack);
4892 	if (err < 0)
4893 		return err;
4894 
4895 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4896 	if (!addr)
4897 		return -EINVAL;
4898 
4899 	ifm = nlmsg_data(nlh);
4900 	if (ifm->ifa_index)
4901 		dev = dev_get_by_index(net, ifm->ifa_index);
4902 
4903 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4904 	if (!ifa) {
4905 		err = -EADDRNOTAVAIL;
4906 		goto errout;
4907 	}
4908 
4909 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4910 	if (!skb) {
4911 		err = -ENOBUFS;
4912 		goto errout_ifa;
4913 	}
4914 
4915 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4916 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4917 	if (err < 0) {
4918 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4919 		WARN_ON(err == -EMSGSIZE);
4920 		kfree_skb(skb);
4921 		goto errout_ifa;
4922 	}
4923 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4924 errout_ifa:
4925 	in6_ifa_put(ifa);
4926 errout:
4927 	if (dev)
4928 		dev_put(dev);
4929 	return err;
4930 }
4931 
4932 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4933 {
4934 	struct sk_buff *skb;
4935 	struct net *net = dev_net(ifa->idev->dev);
4936 	int err = -ENOBUFS;
4937 
4938 	/* Don't send DELADDR notification for TENTATIVE address,
4939 	 * since NEWADDR notification is sent only after removing
4940 	 * TENTATIVE flag, if DAD has not failed.
4941 	 */
4942 	if (ifa->flags & IFA_F_TENTATIVE && !(ifa->flags & IFA_F_DADFAILED) &&
4943 	    event == RTM_DELADDR)
4944 		return;
4945 
4946 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4947 	if (!skb)
4948 		goto errout;
4949 
4950 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4951 	if (err < 0) {
4952 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4953 		WARN_ON(err == -EMSGSIZE);
4954 		kfree_skb(skb);
4955 		goto errout;
4956 	}
4957 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4958 	return;
4959 errout:
4960 	if (err < 0)
4961 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4962 }
4963 
4964 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4965 				__s32 *array, int bytes)
4966 {
4967 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4968 
4969 	memset(array, 0, bytes);
4970 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4971 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4972 	array[DEVCONF_MTU6] = cnf->mtu6;
4973 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4974 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4975 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4976 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4977 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4978 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4979 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4980 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
4981 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
4982 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4983 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4984 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4985 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
4986 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
4987 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
4988 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
4989 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4990 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4991 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4992 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4993 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4994 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4995 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4996 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
4997 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4998 #ifdef CONFIG_IPV6_ROUTER_PREF
4999 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5000 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5001 		jiffies_to_msecs(cnf->rtr_probe_interval);
5002 #ifdef CONFIG_IPV6_ROUTE_INFO
5003 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5004 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5005 #endif
5006 #endif
5007 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5008 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5009 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5010 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5011 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5012 #endif
5013 #ifdef CONFIG_IPV6_MROUTE
5014 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5015 #endif
5016 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5017 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5018 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5019 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5020 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5021 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5022 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5023 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5024 	/* we omit DEVCONF_STABLE_SECRET for now */
5025 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5026 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5027 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5028 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5029 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5030 #ifdef CONFIG_IPV6_SEG6_HMAC
5031 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5032 #endif
5033 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5034 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5035 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5036 }
5037 
5038 static inline size_t inet6_ifla6_size(void)
5039 {
5040 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5041 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5042 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5043 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5044 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5045 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5046 }
5047 
5048 static inline size_t inet6_if_nlmsg_size(void)
5049 {
5050 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5051 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5052 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5053 	       + nla_total_size(4) /* IFLA_MTU */
5054 	       + nla_total_size(4) /* IFLA_LINK */
5055 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5056 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5057 }
5058 
5059 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5060 					int bytes)
5061 {
5062 	int i;
5063 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5064 	BUG_ON(pad < 0);
5065 
5066 	/* Use put_unaligned() because stats may not be aligned for u64. */
5067 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5068 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5069 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5070 
5071 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5072 }
5073 
5074 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5075 					int bytes, size_t syncpoff)
5076 {
5077 	int i, c;
5078 	u64 buff[IPSTATS_MIB_MAX];
5079 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5080 
5081 	BUG_ON(pad < 0);
5082 
5083 	memset(buff, 0, sizeof(buff));
5084 	buff[0] = IPSTATS_MIB_MAX;
5085 
5086 	for_each_possible_cpu(c) {
5087 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5088 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5089 	}
5090 
5091 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5092 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5093 }
5094 
5095 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5096 			     int bytes)
5097 {
5098 	switch (attrtype) {
5099 	case IFLA_INET6_STATS:
5100 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5101 				     offsetof(struct ipstats_mib, syncp));
5102 		break;
5103 	case IFLA_INET6_ICMP6STATS:
5104 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5105 		break;
5106 	}
5107 }
5108 
5109 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5110 				  u32 ext_filter_mask)
5111 {
5112 	struct nlattr *nla;
5113 	struct ifla_cacheinfo ci;
5114 
5115 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5116 		goto nla_put_failure;
5117 	ci.max_reasm_len = IPV6_MAXPLEN;
5118 	ci.tstamp = cstamp_delta(idev->tstamp);
5119 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5120 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5121 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5122 		goto nla_put_failure;
5123 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5124 	if (!nla)
5125 		goto nla_put_failure;
5126 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5127 
5128 	/* XXX - MC not implemented */
5129 
5130 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5131 		return 0;
5132 
5133 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5134 	if (!nla)
5135 		goto nla_put_failure;
5136 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5137 
5138 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5139 	if (!nla)
5140 		goto nla_put_failure;
5141 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5142 
5143 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5144 	if (!nla)
5145 		goto nla_put_failure;
5146 
5147 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5148 		goto nla_put_failure;
5149 
5150 	read_lock_bh(&idev->lock);
5151 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5152 	read_unlock_bh(&idev->lock);
5153 
5154 	return 0;
5155 
5156 nla_put_failure:
5157 	return -EMSGSIZE;
5158 }
5159 
5160 static size_t inet6_get_link_af_size(const struct net_device *dev,
5161 				     u32 ext_filter_mask)
5162 {
5163 	if (!__in6_dev_get(dev))
5164 		return 0;
5165 
5166 	return inet6_ifla6_size();
5167 }
5168 
5169 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5170 			      u32 ext_filter_mask)
5171 {
5172 	struct inet6_dev *idev = __in6_dev_get(dev);
5173 
5174 	if (!idev)
5175 		return -ENODATA;
5176 
5177 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5178 		return -EMSGSIZE;
5179 
5180 	return 0;
5181 }
5182 
5183 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5184 {
5185 	struct inet6_ifaddr *ifp;
5186 	struct net_device *dev = idev->dev;
5187 	bool clear_token, update_rs = false;
5188 	struct in6_addr ll_addr;
5189 
5190 	ASSERT_RTNL();
5191 
5192 	if (!token)
5193 		return -EINVAL;
5194 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5195 		return -EINVAL;
5196 	if (!ipv6_accept_ra(idev))
5197 		return -EINVAL;
5198 	if (idev->cnf.rtr_solicits == 0)
5199 		return -EINVAL;
5200 
5201 	write_lock_bh(&idev->lock);
5202 
5203 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5204 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5205 
5206 	write_unlock_bh(&idev->lock);
5207 
5208 	clear_token = ipv6_addr_any(token);
5209 	if (clear_token)
5210 		goto update_lft;
5211 
5212 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5213 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5214 			     IFA_F_OPTIMISTIC)) {
5215 		/* If we're not ready, then normal ifup will take care
5216 		 * of this. Otherwise, we need to request our rs here.
5217 		 */
5218 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5219 		update_rs = true;
5220 	}
5221 
5222 update_lft:
5223 	write_lock_bh(&idev->lock);
5224 
5225 	if (update_rs) {
5226 		idev->if_flags |= IF_RS_SENT;
5227 		idev->rs_interval = rfc3315_s14_backoff_init(
5228 			idev->cnf.rtr_solicit_interval);
5229 		idev->rs_probes = 1;
5230 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5231 	}
5232 
5233 	/* Well, that's kinda nasty ... */
5234 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5235 		spin_lock(&ifp->lock);
5236 		if (ifp->tokenized) {
5237 			ifp->valid_lft = 0;
5238 			ifp->prefered_lft = 0;
5239 		}
5240 		spin_unlock(&ifp->lock);
5241 	}
5242 
5243 	write_unlock_bh(&idev->lock);
5244 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5245 	addrconf_verify_rtnl();
5246 	return 0;
5247 }
5248 
5249 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5250 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5251 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5252 };
5253 
5254 static int inet6_validate_link_af(const struct net_device *dev,
5255 				  const struct nlattr *nla)
5256 {
5257 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5258 
5259 	if (dev && !__in6_dev_get(dev))
5260 		return -EAFNOSUPPORT;
5261 
5262 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5263 				NULL);
5264 }
5265 
5266 static int check_addr_gen_mode(int mode)
5267 {
5268 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5269 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5270 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5271 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5272 		return -EINVAL;
5273 	return 1;
5274 }
5275 
5276 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5277 				int mode)
5278 {
5279 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5280 	    !idev->cnf.stable_secret.initialized &&
5281 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5282 		return -EINVAL;
5283 	return 1;
5284 }
5285 
5286 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5287 {
5288 	int err = -EINVAL;
5289 	struct inet6_dev *idev = __in6_dev_get(dev);
5290 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5291 
5292 	if (!idev)
5293 		return -EAFNOSUPPORT;
5294 
5295 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5296 		BUG();
5297 
5298 	if (tb[IFLA_INET6_TOKEN]) {
5299 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5300 		if (err)
5301 			return err;
5302 	}
5303 
5304 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5305 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5306 
5307 		if (check_addr_gen_mode(mode) < 0 ||
5308 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5309 			return -EINVAL;
5310 
5311 		idev->cnf.addr_gen_mode = mode;
5312 		err = 0;
5313 	}
5314 
5315 	return err;
5316 }
5317 
5318 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5319 			     u32 portid, u32 seq, int event, unsigned int flags)
5320 {
5321 	struct net_device *dev = idev->dev;
5322 	struct ifinfomsg *hdr;
5323 	struct nlmsghdr *nlh;
5324 	void *protoinfo;
5325 
5326 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5327 	if (!nlh)
5328 		return -EMSGSIZE;
5329 
5330 	hdr = nlmsg_data(nlh);
5331 	hdr->ifi_family = AF_INET6;
5332 	hdr->__ifi_pad = 0;
5333 	hdr->ifi_type = dev->type;
5334 	hdr->ifi_index = dev->ifindex;
5335 	hdr->ifi_flags = dev_get_flags(dev);
5336 	hdr->ifi_change = 0;
5337 
5338 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5339 	    (dev->addr_len &&
5340 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5341 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5342 	    (dev->ifindex != dev_get_iflink(dev) &&
5343 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5344 	    nla_put_u8(skb, IFLA_OPERSTATE,
5345 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5346 		goto nla_put_failure;
5347 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5348 	if (!protoinfo)
5349 		goto nla_put_failure;
5350 
5351 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5352 		goto nla_put_failure;
5353 
5354 	nla_nest_end(skb, protoinfo);
5355 	nlmsg_end(skb, nlh);
5356 	return 0;
5357 
5358 nla_put_failure:
5359 	nlmsg_cancel(skb, nlh);
5360 	return -EMSGSIZE;
5361 }
5362 
5363 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5364 {
5365 	struct net *net = sock_net(skb->sk);
5366 	int h, s_h;
5367 	int idx = 0, s_idx;
5368 	struct net_device *dev;
5369 	struct inet6_dev *idev;
5370 	struct hlist_head *head;
5371 
5372 	s_h = cb->args[0];
5373 	s_idx = cb->args[1];
5374 
5375 	rcu_read_lock();
5376 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5377 		idx = 0;
5378 		head = &net->dev_index_head[h];
5379 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5380 			if (idx < s_idx)
5381 				goto cont;
5382 			idev = __in6_dev_get(dev);
5383 			if (!idev)
5384 				goto cont;
5385 			if (inet6_fill_ifinfo(skb, idev,
5386 					      NETLINK_CB(cb->skb).portid,
5387 					      cb->nlh->nlmsg_seq,
5388 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5389 				goto out;
5390 cont:
5391 			idx++;
5392 		}
5393 	}
5394 out:
5395 	rcu_read_unlock();
5396 	cb->args[1] = idx;
5397 	cb->args[0] = h;
5398 
5399 	return skb->len;
5400 }
5401 
5402 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5403 {
5404 	struct sk_buff *skb;
5405 	struct net *net = dev_net(idev->dev);
5406 	int err = -ENOBUFS;
5407 
5408 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5409 	if (!skb)
5410 		goto errout;
5411 
5412 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5413 	if (err < 0) {
5414 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5415 		WARN_ON(err == -EMSGSIZE);
5416 		kfree_skb(skb);
5417 		goto errout;
5418 	}
5419 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5420 	return;
5421 errout:
5422 	if (err < 0)
5423 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5424 }
5425 
5426 static inline size_t inet6_prefix_nlmsg_size(void)
5427 {
5428 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5429 	       + nla_total_size(sizeof(struct in6_addr))
5430 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5431 }
5432 
5433 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5434 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5435 			     int event, unsigned int flags)
5436 {
5437 	struct prefixmsg *pmsg;
5438 	struct nlmsghdr *nlh;
5439 	struct prefix_cacheinfo	ci;
5440 
5441 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5442 	if (!nlh)
5443 		return -EMSGSIZE;
5444 
5445 	pmsg = nlmsg_data(nlh);
5446 	pmsg->prefix_family = AF_INET6;
5447 	pmsg->prefix_pad1 = 0;
5448 	pmsg->prefix_pad2 = 0;
5449 	pmsg->prefix_ifindex = idev->dev->ifindex;
5450 	pmsg->prefix_len = pinfo->prefix_len;
5451 	pmsg->prefix_type = pinfo->type;
5452 	pmsg->prefix_pad3 = 0;
5453 	pmsg->prefix_flags = 0;
5454 	if (pinfo->onlink)
5455 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5456 	if (pinfo->autoconf)
5457 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5458 
5459 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5460 		goto nla_put_failure;
5461 	ci.preferred_time = ntohl(pinfo->prefered);
5462 	ci.valid_time = ntohl(pinfo->valid);
5463 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5464 		goto nla_put_failure;
5465 	nlmsg_end(skb, nlh);
5466 	return 0;
5467 
5468 nla_put_failure:
5469 	nlmsg_cancel(skb, nlh);
5470 	return -EMSGSIZE;
5471 }
5472 
5473 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5474 			 struct prefix_info *pinfo)
5475 {
5476 	struct sk_buff *skb;
5477 	struct net *net = dev_net(idev->dev);
5478 	int err = -ENOBUFS;
5479 
5480 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5481 	if (!skb)
5482 		goto errout;
5483 
5484 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5485 	if (err < 0) {
5486 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5487 		WARN_ON(err == -EMSGSIZE);
5488 		kfree_skb(skb);
5489 		goto errout;
5490 	}
5491 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5492 	return;
5493 errout:
5494 	if (err < 0)
5495 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5496 }
5497 
5498 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5499 {
5500 	struct net *net = dev_net(ifp->idev->dev);
5501 
5502 	if (event)
5503 		ASSERT_RTNL();
5504 
5505 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5506 
5507 	switch (event) {
5508 	case RTM_NEWADDR:
5509 		/*
5510 		 * If the address was optimistic
5511 		 * we inserted the route at the start of
5512 		 * our DAD process, so we don't need
5513 		 * to do it again
5514 		 */
5515 		if (!rcu_access_pointer(ifp->rt->rt6i_node))
5516 			ip6_ins_rt(ifp->rt);
5517 		if (ifp->idev->cnf.forwarding)
5518 			addrconf_join_anycast(ifp);
5519 		if (!ipv6_addr_any(&ifp->peer_addr))
5520 			addrconf_prefix_route(&ifp->peer_addr, 128,
5521 					      ifp->idev->dev, 0, 0);
5522 		break;
5523 	case RTM_DELADDR:
5524 		if (ifp->idev->cnf.forwarding)
5525 			addrconf_leave_anycast(ifp);
5526 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5527 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5528 			struct rt6_info *rt;
5529 
5530 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5531 						       ifp->idev->dev, 0, 0);
5532 			if (rt)
5533 				ip6_del_rt(rt);
5534 		}
5535 		if (ifp->rt) {
5536 			if (dst_hold_safe(&ifp->rt->dst))
5537 				ip6_del_rt(ifp->rt);
5538 		}
5539 		rt_genid_bump_ipv6(net);
5540 		break;
5541 	}
5542 	atomic_inc(&net->ipv6.dev_addr_genid);
5543 }
5544 
5545 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5546 {
5547 	rcu_read_lock_bh();
5548 	if (likely(ifp->idev->dead == 0))
5549 		__ipv6_ifa_notify(event, ifp);
5550 	rcu_read_unlock_bh();
5551 }
5552 
5553 #ifdef CONFIG_SYSCTL
5554 
5555 static
5556 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5557 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5558 {
5559 	int *valp = ctl->data;
5560 	int val = *valp;
5561 	loff_t pos = *ppos;
5562 	struct ctl_table lctl;
5563 	int ret;
5564 
5565 	/*
5566 	 * ctl->data points to idev->cnf.forwarding, we should
5567 	 * not modify it until we get the rtnl lock.
5568 	 */
5569 	lctl = *ctl;
5570 	lctl.data = &val;
5571 
5572 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5573 
5574 	if (write)
5575 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5576 	if (ret)
5577 		*ppos = pos;
5578 	return ret;
5579 }
5580 
5581 static
5582 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5583 			void __user *buffer, size_t *lenp, loff_t *ppos)
5584 {
5585 	struct inet6_dev *idev = ctl->extra1;
5586 	int min_mtu = IPV6_MIN_MTU;
5587 	struct ctl_table lctl;
5588 
5589 	lctl = *ctl;
5590 	lctl.extra1 = &min_mtu;
5591 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5592 
5593 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5594 }
5595 
5596 static void dev_disable_change(struct inet6_dev *idev)
5597 {
5598 	struct netdev_notifier_info info;
5599 
5600 	if (!idev || !idev->dev)
5601 		return;
5602 
5603 	netdev_notifier_info_init(&info, idev->dev);
5604 	if (idev->cnf.disable_ipv6)
5605 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5606 	else
5607 		addrconf_notify(NULL, NETDEV_UP, &info);
5608 }
5609 
5610 static void addrconf_disable_change(struct net *net, __s32 newf)
5611 {
5612 	struct net_device *dev;
5613 	struct inet6_dev *idev;
5614 
5615 	for_each_netdev(net, dev) {
5616 		idev = __in6_dev_get(dev);
5617 		if (idev) {
5618 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5619 			idev->cnf.disable_ipv6 = newf;
5620 			if (changed)
5621 				dev_disable_change(idev);
5622 		}
5623 	}
5624 }
5625 
5626 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5627 {
5628 	struct net *net;
5629 	int old;
5630 
5631 	if (!rtnl_trylock())
5632 		return restart_syscall();
5633 
5634 	net = (struct net *)table->extra2;
5635 	old = *p;
5636 	*p = newf;
5637 
5638 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5639 		rtnl_unlock();
5640 		return 0;
5641 	}
5642 
5643 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5644 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5645 		addrconf_disable_change(net, newf);
5646 	} else if ((!newf) ^ (!old))
5647 		dev_disable_change((struct inet6_dev *)table->extra1);
5648 
5649 	rtnl_unlock();
5650 	return 0;
5651 }
5652 
5653 static
5654 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5655 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5656 {
5657 	int *valp = ctl->data;
5658 	int val = *valp;
5659 	loff_t pos = *ppos;
5660 	struct ctl_table lctl;
5661 	int ret;
5662 
5663 	/*
5664 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5665 	 * not modify it until we get the rtnl lock.
5666 	 */
5667 	lctl = *ctl;
5668 	lctl.data = &val;
5669 
5670 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5671 
5672 	if (write)
5673 		ret = addrconf_disable_ipv6(ctl, valp, val);
5674 	if (ret)
5675 		*ppos = pos;
5676 	return ret;
5677 }
5678 
5679 static
5680 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5681 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5682 {
5683 	int *valp = ctl->data;
5684 	int ret;
5685 	int old, new;
5686 
5687 	old = *valp;
5688 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5689 	new = *valp;
5690 
5691 	if (write && old != new) {
5692 		struct net *net = ctl->extra2;
5693 
5694 		if (!rtnl_trylock())
5695 			return restart_syscall();
5696 
5697 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5698 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5699 						     NETCONFA_PROXY_NEIGH,
5700 						     NETCONFA_IFINDEX_DEFAULT,
5701 						     net->ipv6.devconf_dflt);
5702 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5703 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5704 						     NETCONFA_PROXY_NEIGH,
5705 						     NETCONFA_IFINDEX_ALL,
5706 						     net->ipv6.devconf_all);
5707 		else {
5708 			struct inet6_dev *idev = ctl->extra1;
5709 
5710 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5711 						     NETCONFA_PROXY_NEIGH,
5712 						     idev->dev->ifindex,
5713 						     &idev->cnf);
5714 		}
5715 		rtnl_unlock();
5716 	}
5717 
5718 	return ret;
5719 }
5720 
5721 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5722 					 void __user *buffer, size_t *lenp,
5723 					 loff_t *ppos)
5724 {
5725 	int ret = 0;
5726 	int new_val;
5727 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5728 	struct net *net = (struct net *)ctl->extra2;
5729 
5730 	if (!rtnl_trylock())
5731 		return restart_syscall();
5732 
5733 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5734 
5735 	if (write) {
5736 		new_val = *((int *)ctl->data);
5737 
5738 		if (check_addr_gen_mode(new_val) < 0) {
5739 			ret = -EINVAL;
5740 			goto out;
5741 		}
5742 
5743 		/* request for default */
5744 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5745 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5746 
5747 		/* request for individual net device */
5748 		} else {
5749 			if (!idev)
5750 				goto out;
5751 
5752 			if (check_stable_privacy(idev, net, new_val) < 0) {
5753 				ret = -EINVAL;
5754 				goto out;
5755 			}
5756 
5757 			if (idev->cnf.addr_gen_mode != new_val) {
5758 				idev->cnf.addr_gen_mode = new_val;
5759 				addrconf_dev_config(idev->dev);
5760 			}
5761 		}
5762 	}
5763 
5764 out:
5765 	rtnl_unlock();
5766 
5767 	return ret;
5768 }
5769 
5770 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5771 					 void __user *buffer, size_t *lenp,
5772 					 loff_t *ppos)
5773 {
5774 	int err;
5775 	struct in6_addr addr;
5776 	char str[IPV6_MAX_STRLEN];
5777 	struct ctl_table lctl = *ctl;
5778 	struct net *net = ctl->extra2;
5779 	struct ipv6_stable_secret *secret = ctl->data;
5780 
5781 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5782 		return -EIO;
5783 
5784 	lctl.maxlen = IPV6_MAX_STRLEN;
5785 	lctl.data = str;
5786 
5787 	if (!rtnl_trylock())
5788 		return restart_syscall();
5789 
5790 	if (!write && !secret->initialized) {
5791 		err = -EIO;
5792 		goto out;
5793 	}
5794 
5795 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5796 	if (err >= sizeof(str)) {
5797 		err = -EIO;
5798 		goto out;
5799 	}
5800 
5801 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5802 	if (err || !write)
5803 		goto out;
5804 
5805 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5806 		err = -EIO;
5807 		goto out;
5808 	}
5809 
5810 	secret->initialized = true;
5811 	secret->secret = addr;
5812 
5813 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5814 		struct net_device *dev;
5815 
5816 		for_each_netdev(net, dev) {
5817 			struct inet6_dev *idev = __in6_dev_get(dev);
5818 
5819 			if (idev) {
5820 				idev->cnf.addr_gen_mode =
5821 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5822 			}
5823 		}
5824 	} else {
5825 		struct inet6_dev *idev = ctl->extra1;
5826 
5827 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5828 	}
5829 
5830 out:
5831 	rtnl_unlock();
5832 
5833 	return err;
5834 }
5835 
5836 static
5837 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5838 						int write,
5839 						void __user *buffer,
5840 						size_t *lenp,
5841 						loff_t *ppos)
5842 {
5843 	int *valp = ctl->data;
5844 	int val = *valp;
5845 	loff_t pos = *ppos;
5846 	struct ctl_table lctl;
5847 	int ret;
5848 
5849 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5850 	 * we should not modify it until we get the rtnl lock.
5851 	 */
5852 	lctl = *ctl;
5853 	lctl.data = &val;
5854 
5855 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5856 
5857 	if (write)
5858 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5859 	if (ret)
5860 		*ppos = pos;
5861 	return ret;
5862 }
5863 
5864 static
5865 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5866 {
5867 	if (rt) {
5868 		if (action)
5869 			rt->dst.flags |= DST_NOPOLICY;
5870 		else
5871 			rt->dst.flags &= ~DST_NOPOLICY;
5872 	}
5873 }
5874 
5875 static
5876 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5877 {
5878 	struct inet6_ifaddr *ifa;
5879 
5880 	read_lock_bh(&idev->lock);
5881 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5882 		spin_lock(&ifa->lock);
5883 		if (ifa->rt) {
5884 			struct rt6_info *rt = ifa->rt;
5885 			int cpu;
5886 
5887 			rcu_read_lock();
5888 			addrconf_set_nopolicy(ifa->rt, val);
5889 			if (rt->rt6i_pcpu) {
5890 				for_each_possible_cpu(cpu) {
5891 					struct rt6_info **rtp;
5892 
5893 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5894 					addrconf_set_nopolicy(*rtp, val);
5895 				}
5896 			}
5897 			rcu_read_unlock();
5898 		}
5899 		spin_unlock(&ifa->lock);
5900 	}
5901 	read_unlock_bh(&idev->lock);
5902 }
5903 
5904 static
5905 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
5906 {
5907 	struct inet6_dev *idev;
5908 	struct net *net;
5909 
5910 	if (!rtnl_trylock())
5911 		return restart_syscall();
5912 
5913 	*valp = val;
5914 
5915 	net = (struct net *)ctl->extra2;
5916 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
5917 		rtnl_unlock();
5918 		return 0;
5919 	}
5920 
5921 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
5922 		struct net_device *dev;
5923 
5924 		for_each_netdev(net, dev) {
5925 			idev = __in6_dev_get(dev);
5926 			if (idev)
5927 				addrconf_disable_policy_idev(idev, val);
5928 		}
5929 	} else {
5930 		idev = (struct inet6_dev *)ctl->extra1;
5931 		addrconf_disable_policy_idev(idev, val);
5932 	}
5933 
5934 	rtnl_unlock();
5935 	return 0;
5936 }
5937 
5938 static
5939 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
5940 				   void __user *buffer, size_t *lenp,
5941 				   loff_t *ppos)
5942 {
5943 	int *valp = ctl->data;
5944 	int val = *valp;
5945 	loff_t pos = *ppos;
5946 	struct ctl_table lctl;
5947 	int ret;
5948 
5949 	lctl = *ctl;
5950 	lctl.data = &val;
5951 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5952 
5953 	if (write && (*valp != val))
5954 		ret = addrconf_disable_policy(ctl, valp, val);
5955 
5956 	if (ret)
5957 		*ppos = pos;
5958 
5959 	return ret;
5960 }
5961 
5962 static int minus_one = -1;
5963 static const int one = 1;
5964 static const int two_five_five = 255;
5965 
5966 static const struct ctl_table addrconf_sysctl[] = {
5967 	{
5968 		.procname	= "forwarding",
5969 		.data		= &ipv6_devconf.forwarding,
5970 		.maxlen		= sizeof(int),
5971 		.mode		= 0644,
5972 		.proc_handler	= addrconf_sysctl_forward,
5973 	},
5974 	{
5975 		.procname	= "hop_limit",
5976 		.data		= &ipv6_devconf.hop_limit,
5977 		.maxlen		= sizeof(int),
5978 		.mode		= 0644,
5979 		.proc_handler	= proc_dointvec_minmax,
5980 		.extra1		= (void *)&one,
5981 		.extra2		= (void *)&two_five_five,
5982 	},
5983 	{
5984 		.procname	= "mtu",
5985 		.data		= &ipv6_devconf.mtu6,
5986 		.maxlen		= sizeof(int),
5987 		.mode		= 0644,
5988 		.proc_handler	= addrconf_sysctl_mtu,
5989 	},
5990 	{
5991 		.procname	= "accept_ra",
5992 		.data		= &ipv6_devconf.accept_ra,
5993 		.maxlen		= sizeof(int),
5994 		.mode		= 0644,
5995 		.proc_handler	= proc_dointvec,
5996 	},
5997 	{
5998 		.procname	= "accept_redirects",
5999 		.data		= &ipv6_devconf.accept_redirects,
6000 		.maxlen		= sizeof(int),
6001 		.mode		= 0644,
6002 		.proc_handler	= proc_dointvec,
6003 	},
6004 	{
6005 		.procname	= "autoconf",
6006 		.data		= &ipv6_devconf.autoconf,
6007 		.maxlen		= sizeof(int),
6008 		.mode		= 0644,
6009 		.proc_handler	= proc_dointvec,
6010 	},
6011 	{
6012 		.procname	= "dad_transmits",
6013 		.data		= &ipv6_devconf.dad_transmits,
6014 		.maxlen		= sizeof(int),
6015 		.mode		= 0644,
6016 		.proc_handler	= proc_dointvec,
6017 	},
6018 	{
6019 		.procname	= "router_solicitations",
6020 		.data		= &ipv6_devconf.rtr_solicits,
6021 		.maxlen		= sizeof(int),
6022 		.mode		= 0644,
6023 		.proc_handler	= proc_dointvec_minmax,
6024 		.extra1		= &minus_one,
6025 	},
6026 	{
6027 		.procname	= "router_solicitation_interval",
6028 		.data		= &ipv6_devconf.rtr_solicit_interval,
6029 		.maxlen		= sizeof(int),
6030 		.mode		= 0644,
6031 		.proc_handler	= proc_dointvec_jiffies,
6032 	},
6033 	{
6034 		.procname	= "router_solicitation_max_interval",
6035 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6036 		.maxlen		= sizeof(int),
6037 		.mode		= 0644,
6038 		.proc_handler	= proc_dointvec_jiffies,
6039 	},
6040 	{
6041 		.procname	= "router_solicitation_delay",
6042 		.data		= &ipv6_devconf.rtr_solicit_delay,
6043 		.maxlen		= sizeof(int),
6044 		.mode		= 0644,
6045 		.proc_handler	= proc_dointvec_jiffies,
6046 	},
6047 	{
6048 		.procname	= "force_mld_version",
6049 		.data		= &ipv6_devconf.force_mld_version,
6050 		.maxlen		= sizeof(int),
6051 		.mode		= 0644,
6052 		.proc_handler	= proc_dointvec,
6053 	},
6054 	{
6055 		.procname	= "mldv1_unsolicited_report_interval",
6056 		.data		=
6057 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6058 		.maxlen		= sizeof(int),
6059 		.mode		= 0644,
6060 		.proc_handler	= proc_dointvec_ms_jiffies,
6061 	},
6062 	{
6063 		.procname	= "mldv2_unsolicited_report_interval",
6064 		.data		=
6065 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6066 		.maxlen		= sizeof(int),
6067 		.mode		= 0644,
6068 		.proc_handler	= proc_dointvec_ms_jiffies,
6069 	},
6070 	{
6071 		.procname	= "use_tempaddr",
6072 		.data		= &ipv6_devconf.use_tempaddr,
6073 		.maxlen		= sizeof(int),
6074 		.mode		= 0644,
6075 		.proc_handler	= proc_dointvec,
6076 	},
6077 	{
6078 		.procname	= "temp_valid_lft",
6079 		.data		= &ipv6_devconf.temp_valid_lft,
6080 		.maxlen		= sizeof(int),
6081 		.mode		= 0644,
6082 		.proc_handler	= proc_dointvec,
6083 	},
6084 	{
6085 		.procname	= "temp_prefered_lft",
6086 		.data		= &ipv6_devconf.temp_prefered_lft,
6087 		.maxlen		= sizeof(int),
6088 		.mode		= 0644,
6089 		.proc_handler	= proc_dointvec,
6090 	},
6091 	{
6092 		.procname	= "regen_max_retry",
6093 		.data		= &ipv6_devconf.regen_max_retry,
6094 		.maxlen		= sizeof(int),
6095 		.mode		= 0644,
6096 		.proc_handler	= proc_dointvec,
6097 	},
6098 	{
6099 		.procname	= "max_desync_factor",
6100 		.data		= &ipv6_devconf.max_desync_factor,
6101 		.maxlen		= sizeof(int),
6102 		.mode		= 0644,
6103 		.proc_handler	= proc_dointvec,
6104 	},
6105 	{
6106 		.procname	= "max_addresses",
6107 		.data		= &ipv6_devconf.max_addresses,
6108 		.maxlen		= sizeof(int),
6109 		.mode		= 0644,
6110 		.proc_handler	= proc_dointvec,
6111 	},
6112 	{
6113 		.procname	= "accept_ra_defrtr",
6114 		.data		= &ipv6_devconf.accept_ra_defrtr,
6115 		.maxlen		= sizeof(int),
6116 		.mode		= 0644,
6117 		.proc_handler	= proc_dointvec,
6118 	},
6119 	{
6120 		.procname	= "accept_ra_min_hop_limit",
6121 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6122 		.maxlen		= sizeof(int),
6123 		.mode		= 0644,
6124 		.proc_handler	= proc_dointvec,
6125 	},
6126 	{
6127 		.procname	= "accept_ra_pinfo",
6128 		.data		= &ipv6_devconf.accept_ra_pinfo,
6129 		.maxlen		= sizeof(int),
6130 		.mode		= 0644,
6131 		.proc_handler	= proc_dointvec,
6132 	},
6133 #ifdef CONFIG_IPV6_ROUTER_PREF
6134 	{
6135 		.procname	= "accept_ra_rtr_pref",
6136 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6137 		.maxlen		= sizeof(int),
6138 		.mode		= 0644,
6139 		.proc_handler	= proc_dointvec,
6140 	},
6141 	{
6142 		.procname	= "router_probe_interval",
6143 		.data		= &ipv6_devconf.rtr_probe_interval,
6144 		.maxlen		= sizeof(int),
6145 		.mode		= 0644,
6146 		.proc_handler	= proc_dointvec_jiffies,
6147 	},
6148 #ifdef CONFIG_IPV6_ROUTE_INFO
6149 	{
6150 		.procname	= "accept_ra_rt_info_min_plen",
6151 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6152 		.maxlen		= sizeof(int),
6153 		.mode		= 0644,
6154 		.proc_handler	= proc_dointvec,
6155 	},
6156 	{
6157 		.procname	= "accept_ra_rt_info_max_plen",
6158 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6159 		.maxlen		= sizeof(int),
6160 		.mode		= 0644,
6161 		.proc_handler	= proc_dointvec,
6162 	},
6163 #endif
6164 #endif
6165 	{
6166 		.procname	= "proxy_ndp",
6167 		.data		= &ipv6_devconf.proxy_ndp,
6168 		.maxlen		= sizeof(int),
6169 		.mode		= 0644,
6170 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6171 	},
6172 	{
6173 		.procname	= "accept_source_route",
6174 		.data		= &ipv6_devconf.accept_source_route,
6175 		.maxlen		= sizeof(int),
6176 		.mode		= 0644,
6177 		.proc_handler	= proc_dointvec,
6178 	},
6179 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6180 	{
6181 		.procname	= "optimistic_dad",
6182 		.data		= &ipv6_devconf.optimistic_dad,
6183 		.maxlen		= sizeof(int),
6184 		.mode		= 0644,
6185 		.proc_handler   = proc_dointvec,
6186 	},
6187 	{
6188 		.procname	= "use_optimistic",
6189 		.data		= &ipv6_devconf.use_optimistic,
6190 		.maxlen		= sizeof(int),
6191 		.mode		= 0644,
6192 		.proc_handler	= proc_dointvec,
6193 	},
6194 #endif
6195 #ifdef CONFIG_IPV6_MROUTE
6196 	{
6197 		.procname	= "mc_forwarding",
6198 		.data		= &ipv6_devconf.mc_forwarding,
6199 		.maxlen		= sizeof(int),
6200 		.mode		= 0444,
6201 		.proc_handler	= proc_dointvec,
6202 	},
6203 #endif
6204 	{
6205 		.procname	= "disable_ipv6",
6206 		.data		= &ipv6_devconf.disable_ipv6,
6207 		.maxlen		= sizeof(int),
6208 		.mode		= 0644,
6209 		.proc_handler	= addrconf_sysctl_disable,
6210 	},
6211 	{
6212 		.procname	= "accept_dad",
6213 		.data		= &ipv6_devconf.accept_dad,
6214 		.maxlen		= sizeof(int),
6215 		.mode		= 0644,
6216 		.proc_handler	= proc_dointvec,
6217 	},
6218 	{
6219 		.procname	= "force_tllao",
6220 		.data		= &ipv6_devconf.force_tllao,
6221 		.maxlen		= sizeof(int),
6222 		.mode		= 0644,
6223 		.proc_handler	= proc_dointvec
6224 	},
6225 	{
6226 		.procname	= "ndisc_notify",
6227 		.data		= &ipv6_devconf.ndisc_notify,
6228 		.maxlen		= sizeof(int),
6229 		.mode		= 0644,
6230 		.proc_handler	= proc_dointvec
6231 	},
6232 	{
6233 		.procname	= "suppress_frag_ndisc",
6234 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6235 		.maxlen		= sizeof(int),
6236 		.mode		= 0644,
6237 		.proc_handler	= proc_dointvec
6238 	},
6239 	{
6240 		.procname	= "accept_ra_from_local",
6241 		.data		= &ipv6_devconf.accept_ra_from_local,
6242 		.maxlen		= sizeof(int),
6243 		.mode		= 0644,
6244 		.proc_handler	= proc_dointvec,
6245 	},
6246 	{
6247 		.procname	= "accept_ra_mtu",
6248 		.data		= &ipv6_devconf.accept_ra_mtu,
6249 		.maxlen		= sizeof(int),
6250 		.mode		= 0644,
6251 		.proc_handler	= proc_dointvec,
6252 	},
6253 	{
6254 		.procname	= "stable_secret",
6255 		.data		= &ipv6_devconf.stable_secret,
6256 		.maxlen		= IPV6_MAX_STRLEN,
6257 		.mode		= 0600,
6258 		.proc_handler	= addrconf_sysctl_stable_secret,
6259 	},
6260 	{
6261 		.procname	= "use_oif_addrs_only",
6262 		.data		= &ipv6_devconf.use_oif_addrs_only,
6263 		.maxlen		= sizeof(int),
6264 		.mode		= 0644,
6265 		.proc_handler	= proc_dointvec,
6266 	},
6267 	{
6268 		.procname	= "ignore_routes_with_linkdown",
6269 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6270 		.maxlen		= sizeof(int),
6271 		.mode		= 0644,
6272 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6273 	},
6274 	{
6275 		.procname	= "drop_unicast_in_l2_multicast",
6276 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6277 		.maxlen		= sizeof(int),
6278 		.mode		= 0644,
6279 		.proc_handler	= proc_dointvec,
6280 	},
6281 	{
6282 		.procname	= "drop_unsolicited_na",
6283 		.data		= &ipv6_devconf.drop_unsolicited_na,
6284 		.maxlen		= sizeof(int),
6285 		.mode		= 0644,
6286 		.proc_handler	= proc_dointvec,
6287 	},
6288 	{
6289 		.procname	= "keep_addr_on_down",
6290 		.data		= &ipv6_devconf.keep_addr_on_down,
6291 		.maxlen		= sizeof(int),
6292 		.mode		= 0644,
6293 		.proc_handler	= proc_dointvec,
6294 
6295 	},
6296 	{
6297 		.procname	= "seg6_enabled",
6298 		.data		= &ipv6_devconf.seg6_enabled,
6299 		.maxlen		= sizeof(int),
6300 		.mode		= 0644,
6301 		.proc_handler	= proc_dointvec,
6302 	},
6303 #ifdef CONFIG_IPV6_SEG6_HMAC
6304 	{
6305 		.procname	= "seg6_require_hmac",
6306 		.data		= &ipv6_devconf.seg6_require_hmac,
6307 		.maxlen		= sizeof(int),
6308 		.mode		= 0644,
6309 		.proc_handler	= proc_dointvec,
6310 	},
6311 #endif
6312 	{
6313 		.procname       = "enhanced_dad",
6314 		.data           = &ipv6_devconf.enhanced_dad,
6315 		.maxlen         = sizeof(int),
6316 		.mode           = 0644,
6317 		.proc_handler   = proc_dointvec,
6318 	},
6319 	{
6320 		.procname		= "addr_gen_mode",
6321 		.data			= &ipv6_devconf.addr_gen_mode,
6322 		.maxlen			= sizeof(int),
6323 		.mode			= 0644,
6324 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6325 	},
6326 	{
6327 		.procname       = "disable_policy",
6328 		.data           = &ipv6_devconf.disable_policy,
6329 		.maxlen         = sizeof(int),
6330 		.mode           = 0644,
6331 		.proc_handler   = addrconf_sysctl_disable_policy,
6332 	},
6333 	{
6334 		/* sentinel */
6335 	}
6336 };
6337 
6338 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6339 		struct inet6_dev *idev, struct ipv6_devconf *p)
6340 {
6341 	int i, ifindex;
6342 	struct ctl_table *table;
6343 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6344 
6345 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6346 	if (!table)
6347 		goto out;
6348 
6349 	for (i = 0; table[i].data; i++) {
6350 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6351 		/* If one of these is already set, then it is not safe to
6352 		 * overwrite either of them: this makes proc_dointvec_minmax
6353 		 * usable.
6354 		 */
6355 		if (!table[i].extra1 && !table[i].extra2) {
6356 			table[i].extra1 = idev; /* embedded; no ref */
6357 			table[i].extra2 = net;
6358 		}
6359 	}
6360 
6361 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6362 
6363 	p->sysctl_header = register_net_sysctl(net, path, table);
6364 	if (!p->sysctl_header)
6365 		goto free;
6366 
6367 	if (!strcmp(dev_name, "all"))
6368 		ifindex = NETCONFA_IFINDEX_ALL;
6369 	else if (!strcmp(dev_name, "default"))
6370 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6371 	else
6372 		ifindex = idev->dev->ifindex;
6373 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6374 				     ifindex, p);
6375 	return 0;
6376 
6377 free:
6378 	kfree(table);
6379 out:
6380 	return -ENOBUFS;
6381 }
6382 
6383 static void __addrconf_sysctl_unregister(struct net *net,
6384 					 struct ipv6_devconf *p, int ifindex)
6385 {
6386 	struct ctl_table *table;
6387 
6388 	if (!p->sysctl_header)
6389 		return;
6390 
6391 	table = p->sysctl_header->ctl_table_arg;
6392 	unregister_net_sysctl_table(p->sysctl_header);
6393 	p->sysctl_header = NULL;
6394 	kfree(table);
6395 
6396 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6397 }
6398 
6399 static int addrconf_sysctl_register(struct inet6_dev *idev)
6400 {
6401 	int err;
6402 
6403 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6404 		return -EINVAL;
6405 
6406 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6407 				    &ndisc_ifinfo_sysctl_change);
6408 	if (err)
6409 		return err;
6410 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6411 					 idev, &idev->cnf);
6412 	if (err)
6413 		neigh_sysctl_unregister(idev->nd_parms);
6414 
6415 	return err;
6416 }
6417 
6418 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6419 {
6420 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6421 				     idev->dev->ifindex);
6422 	neigh_sysctl_unregister(idev->nd_parms);
6423 }
6424 
6425 
6426 #endif
6427 
6428 static int __net_init addrconf_init_net(struct net *net)
6429 {
6430 	int err = -ENOMEM;
6431 	struct ipv6_devconf *all, *dflt;
6432 
6433 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6434 	if (!all)
6435 		goto err_alloc_all;
6436 
6437 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6438 	if (!dflt)
6439 		goto err_alloc_dflt;
6440 
6441 	/* these will be inherited by all namespaces */
6442 	dflt->autoconf = ipv6_defaults.autoconf;
6443 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6444 
6445 	dflt->stable_secret.initialized = false;
6446 	all->stable_secret.initialized = false;
6447 
6448 	net->ipv6.devconf_all = all;
6449 	net->ipv6.devconf_dflt = dflt;
6450 
6451 #ifdef CONFIG_SYSCTL
6452 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6453 	if (err < 0)
6454 		goto err_reg_all;
6455 
6456 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6457 	if (err < 0)
6458 		goto err_reg_dflt;
6459 #endif
6460 	return 0;
6461 
6462 #ifdef CONFIG_SYSCTL
6463 err_reg_dflt:
6464 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6465 err_reg_all:
6466 	kfree(dflt);
6467 #endif
6468 err_alloc_dflt:
6469 	kfree(all);
6470 err_alloc_all:
6471 	return err;
6472 }
6473 
6474 static void __net_exit addrconf_exit_net(struct net *net)
6475 {
6476 #ifdef CONFIG_SYSCTL
6477 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6478 				     NETCONFA_IFINDEX_DEFAULT);
6479 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6480 				     NETCONFA_IFINDEX_ALL);
6481 #endif
6482 	kfree(net->ipv6.devconf_dflt);
6483 	kfree(net->ipv6.devconf_all);
6484 }
6485 
6486 static struct pernet_operations addrconf_ops = {
6487 	.init = addrconf_init_net,
6488 	.exit = addrconf_exit_net,
6489 };
6490 
6491 static struct rtnl_af_ops inet6_ops __read_mostly = {
6492 	.family		  = AF_INET6,
6493 	.fill_link_af	  = inet6_fill_link_af,
6494 	.get_link_af_size = inet6_get_link_af_size,
6495 	.validate_link_af = inet6_validate_link_af,
6496 	.set_link_af	  = inet6_set_link_af,
6497 };
6498 
6499 /*
6500  *	Init / cleanup code
6501  */
6502 
6503 int __init addrconf_init(void)
6504 {
6505 	struct inet6_dev *idev;
6506 	int i, err;
6507 
6508 	err = ipv6_addr_label_init();
6509 	if (err < 0) {
6510 		pr_crit("%s: cannot initialize default policy table: %d\n",
6511 			__func__, err);
6512 		goto out;
6513 	}
6514 
6515 	err = register_pernet_subsys(&addrconf_ops);
6516 	if (err < 0)
6517 		goto out_addrlabel;
6518 
6519 	addrconf_wq = create_workqueue("ipv6_addrconf");
6520 	if (!addrconf_wq) {
6521 		err = -ENOMEM;
6522 		goto out_nowq;
6523 	}
6524 
6525 	/* The addrconf netdev notifier requires that loopback_dev
6526 	 * has it's ipv6 private information allocated and setup
6527 	 * before it can bring up and give link-local addresses
6528 	 * to other devices which are up.
6529 	 *
6530 	 * Unfortunately, loopback_dev is not necessarily the first
6531 	 * entry in the global dev_base list of net devices.  In fact,
6532 	 * it is likely to be the very last entry on that list.
6533 	 * So this causes the notifier registry below to try and
6534 	 * give link-local addresses to all devices besides loopback_dev
6535 	 * first, then loopback_dev, which cases all the non-loopback_dev
6536 	 * devices to fail to get a link-local address.
6537 	 *
6538 	 * So, as a temporary fix, allocate the ipv6 structure for
6539 	 * loopback_dev first by hand.
6540 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6541 	 * device and it being up should be removed.
6542 	 */
6543 	rtnl_lock();
6544 	idev = ipv6_add_dev(init_net.loopback_dev);
6545 	rtnl_unlock();
6546 	if (IS_ERR(idev)) {
6547 		err = PTR_ERR(idev);
6548 		goto errlo;
6549 	}
6550 
6551 	ip6_route_init_special_entries();
6552 
6553 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6554 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6555 
6556 	register_netdevice_notifier(&ipv6_dev_notf);
6557 
6558 	addrconf_verify();
6559 
6560 	rtnl_af_register(&inet6_ops);
6561 
6562 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6563 			      0);
6564 	if (err < 0)
6565 		goto errout;
6566 
6567 	/* Only the first call to __rtnl_register can fail */
6568 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, 0);
6569 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, 0);
6570 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6571 			inet6_dump_ifaddr, RTNL_FLAG_DOIT_UNLOCKED);
6572 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6573 			inet6_dump_ifmcaddr, 0);
6574 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6575 			inet6_dump_ifacaddr, 0);
6576 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6577 			inet6_netconf_dump_devconf, RTNL_FLAG_DOIT_UNLOCKED);
6578 
6579 	ipv6_addr_label_rtnl_register();
6580 
6581 	return 0;
6582 errout:
6583 	rtnl_af_unregister(&inet6_ops);
6584 	unregister_netdevice_notifier(&ipv6_dev_notf);
6585 errlo:
6586 	destroy_workqueue(addrconf_wq);
6587 out_nowq:
6588 	unregister_pernet_subsys(&addrconf_ops);
6589 out_addrlabel:
6590 	ipv6_addr_label_cleanup();
6591 out:
6592 	return err;
6593 }
6594 
6595 void addrconf_cleanup(void)
6596 {
6597 	struct net_device *dev;
6598 	int i;
6599 
6600 	unregister_netdevice_notifier(&ipv6_dev_notf);
6601 	unregister_pernet_subsys(&addrconf_ops);
6602 	ipv6_addr_label_cleanup();
6603 
6604 	rtnl_af_unregister(&inet6_ops);
6605 
6606 	rtnl_lock();
6607 
6608 	/* clean dev list */
6609 	for_each_netdev(&init_net, dev) {
6610 		if (__in6_dev_get(dev) == NULL)
6611 			continue;
6612 		addrconf_ifdown(dev, 1);
6613 	}
6614 	addrconf_ifdown(init_net.loopback_dev, 2);
6615 
6616 	/*
6617 	 *	Check hash table.
6618 	 */
6619 	spin_lock_bh(&addrconf_hash_lock);
6620 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6621 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6622 	spin_unlock_bh(&addrconf_hash_lock);
6623 	cancel_delayed_work(&addr_chk_work);
6624 	rtnl_unlock();
6625 
6626 	destroy_workqueue(addrconf_wq);
6627 }
6628