xref: /openbmc/linux/net/ipv6/addrconf.c (revision 6aa7de05)
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(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 a valid qdisc is available */
307 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
308 {
309 	return !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_qdisc_ok(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 netconfmsg *ncm;
620 	struct sk_buff *skb;
621 	struct ipv6_devconf *devconf;
622 	struct inet6_dev *in6_dev;
623 	struct net_device *dev;
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 		goto errout;
631 
632 	err = -EINVAL;
633 	if (!tb[NETCONFA_IFINDEX])
634 		goto errout;
635 
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 			goto errout;
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_ATOMIC);
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 	return err;
673 }
674 
675 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
676 				      struct netlink_callback *cb)
677 {
678 	struct net *net = sock_net(skb->sk);
679 	int h, s_h;
680 	int idx, s_idx;
681 	struct net_device *dev;
682 	struct inet6_dev *idev;
683 	struct hlist_head *head;
684 
685 	s_h = cb->args[0];
686 	s_idx = idx = cb->args[1];
687 
688 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
689 		idx = 0;
690 		head = &net->dev_index_head[h];
691 		rcu_read_lock();
692 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
693 			  net->dev_base_seq;
694 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
695 			if (idx < s_idx)
696 				goto cont;
697 			idev = __in6_dev_get(dev);
698 			if (!idev)
699 				goto cont;
700 
701 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
702 						       &idev->cnf,
703 						       NETLINK_CB(cb->skb).portid,
704 						       cb->nlh->nlmsg_seq,
705 						       RTM_NEWNETCONF,
706 						       NLM_F_MULTI,
707 						       NETCONFA_ALL) < 0) {
708 				rcu_read_unlock();
709 				goto done;
710 			}
711 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
712 cont:
713 			idx++;
714 		}
715 		rcu_read_unlock();
716 	}
717 	if (h == NETDEV_HASHENTRIES) {
718 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
719 					       net->ipv6.devconf_all,
720 					       NETLINK_CB(cb->skb).portid,
721 					       cb->nlh->nlmsg_seq,
722 					       RTM_NEWNETCONF, NLM_F_MULTI,
723 					       NETCONFA_ALL) < 0)
724 			goto done;
725 		else
726 			h++;
727 	}
728 	if (h == NETDEV_HASHENTRIES + 1) {
729 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
730 					       net->ipv6.devconf_dflt,
731 					       NETLINK_CB(cb->skb).portid,
732 					       cb->nlh->nlmsg_seq,
733 					       RTM_NEWNETCONF, NLM_F_MULTI,
734 					       NETCONFA_ALL) < 0)
735 			goto done;
736 		else
737 			h++;
738 	}
739 done:
740 	cb->args[0] = h;
741 	cb->args[1] = idx;
742 
743 	return skb->len;
744 }
745 
746 #ifdef CONFIG_SYSCTL
747 static void dev_forward_change(struct inet6_dev *idev)
748 {
749 	struct net_device *dev;
750 	struct inet6_ifaddr *ifa;
751 
752 	if (!idev)
753 		return;
754 	dev = idev->dev;
755 	if (idev->cnf.forwarding)
756 		dev_disable_lro(dev);
757 	if (dev->flags & IFF_MULTICAST) {
758 		if (idev->cnf.forwarding) {
759 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
760 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
761 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
762 		} else {
763 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
764 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
765 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
766 		}
767 	}
768 
769 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
770 		if (ifa->flags&IFA_F_TENTATIVE)
771 			continue;
772 		if (idev->cnf.forwarding)
773 			addrconf_join_anycast(ifa);
774 		else
775 			addrconf_leave_anycast(ifa);
776 	}
777 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
778 				     NETCONFA_FORWARDING,
779 				     dev->ifindex, &idev->cnf);
780 }
781 
782 
783 static void addrconf_forward_change(struct net *net, __s32 newf)
784 {
785 	struct net_device *dev;
786 	struct inet6_dev *idev;
787 
788 	for_each_netdev(net, dev) {
789 		idev = __in6_dev_get(dev);
790 		if (idev) {
791 			int changed = (!idev->cnf.forwarding) ^ (!newf);
792 			idev->cnf.forwarding = newf;
793 			if (changed)
794 				dev_forward_change(idev);
795 		}
796 	}
797 }
798 
799 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
800 {
801 	struct net *net;
802 	int old;
803 
804 	if (!rtnl_trylock())
805 		return restart_syscall();
806 
807 	net = (struct net *)table->extra2;
808 	old = *p;
809 	*p = newf;
810 
811 	if (p == &net->ipv6.devconf_dflt->forwarding) {
812 		if ((!newf) ^ (!old))
813 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
814 						     NETCONFA_FORWARDING,
815 						     NETCONFA_IFINDEX_DEFAULT,
816 						     net->ipv6.devconf_dflt);
817 		rtnl_unlock();
818 		return 0;
819 	}
820 
821 	if (p == &net->ipv6.devconf_all->forwarding) {
822 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
823 
824 		net->ipv6.devconf_dflt->forwarding = newf;
825 		if ((!newf) ^ (!old_dflt))
826 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
827 						     NETCONFA_FORWARDING,
828 						     NETCONFA_IFINDEX_DEFAULT,
829 						     net->ipv6.devconf_dflt);
830 
831 		addrconf_forward_change(net, newf);
832 		if ((!newf) ^ (!old))
833 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
834 						     NETCONFA_FORWARDING,
835 						     NETCONFA_IFINDEX_ALL,
836 						     net->ipv6.devconf_all);
837 	} else if ((!newf) ^ (!old))
838 		dev_forward_change((struct inet6_dev *)table->extra1);
839 	rtnl_unlock();
840 
841 	if (newf)
842 		rt6_purge_dflt_routers(net);
843 	return 1;
844 }
845 
846 static void addrconf_linkdown_change(struct net *net, __s32 newf)
847 {
848 	struct net_device *dev;
849 	struct inet6_dev *idev;
850 
851 	for_each_netdev(net, dev) {
852 		idev = __in6_dev_get(dev);
853 		if (idev) {
854 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
855 
856 			idev->cnf.ignore_routes_with_linkdown = newf;
857 			if (changed)
858 				inet6_netconf_notify_devconf(dev_net(dev),
859 							     RTM_NEWNETCONF,
860 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
861 							     dev->ifindex,
862 							     &idev->cnf);
863 		}
864 	}
865 }
866 
867 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
868 {
869 	struct net *net;
870 	int old;
871 
872 	if (!rtnl_trylock())
873 		return restart_syscall();
874 
875 	net = (struct net *)table->extra2;
876 	old = *p;
877 	*p = newf;
878 
879 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
880 		if ((!newf) ^ (!old))
881 			inet6_netconf_notify_devconf(net,
882 						     RTM_NEWNETCONF,
883 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
884 						     NETCONFA_IFINDEX_DEFAULT,
885 						     net->ipv6.devconf_dflt);
886 		rtnl_unlock();
887 		return 0;
888 	}
889 
890 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
891 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
892 		addrconf_linkdown_change(net, newf);
893 		if ((!newf) ^ (!old))
894 			inet6_netconf_notify_devconf(net,
895 						     RTM_NEWNETCONF,
896 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
897 						     NETCONFA_IFINDEX_ALL,
898 						     net->ipv6.devconf_all);
899 	}
900 	rtnl_unlock();
901 
902 	return 1;
903 }
904 
905 #endif
906 
907 /* Nobody refers to this ifaddr, destroy it */
908 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
909 {
910 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
911 
912 #ifdef NET_REFCNT_DEBUG
913 	pr_debug("%s\n", __func__);
914 #endif
915 
916 	in6_dev_put(ifp->idev);
917 
918 	if (cancel_delayed_work(&ifp->dad_work))
919 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
920 			  ifp);
921 
922 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
923 		pr_warn("Freeing alive inet6 address %p\n", ifp);
924 		return;
925 	}
926 	ip6_rt_put(ifp->rt);
927 
928 	kfree_rcu(ifp, rcu);
929 }
930 
931 static void
932 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
933 {
934 	struct list_head *p;
935 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
936 
937 	/*
938 	 * Each device address list is sorted in order of scope -
939 	 * global before linklocal.
940 	 */
941 	list_for_each(p, &idev->addr_list) {
942 		struct inet6_ifaddr *ifa
943 			= list_entry(p, struct inet6_ifaddr, if_list);
944 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
945 			break;
946 	}
947 
948 	list_add_tail(&ifp->if_list, p);
949 }
950 
951 static u32 inet6_addr_hash(const struct in6_addr *addr)
952 {
953 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
954 }
955 
956 /* On success it returns ifp with increased reference count */
957 
958 static struct inet6_ifaddr *
959 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
960 	      const struct in6_addr *peer_addr, int pfxlen,
961 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
962 {
963 	struct net *net = dev_net(idev->dev);
964 	struct inet6_ifaddr *ifa = NULL;
965 	struct rt6_info *rt;
966 	struct in6_validator_info i6vi;
967 	unsigned int hash;
968 	int err = 0;
969 	int addr_type = ipv6_addr_type(addr);
970 
971 	if (addr_type == IPV6_ADDR_ANY ||
972 	    addr_type & IPV6_ADDR_MULTICAST ||
973 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
974 	     addr_type & IPV6_ADDR_LOOPBACK))
975 		return ERR_PTR(-EADDRNOTAVAIL);
976 
977 	rcu_read_lock_bh();
978 
979 	in6_dev_hold(idev);
980 
981 	if (idev->dead) {
982 		err = -ENODEV;			/*XXX*/
983 		goto out2;
984 	}
985 
986 	if (idev->cnf.disable_ipv6) {
987 		err = -EACCES;
988 		goto out2;
989 	}
990 
991 	i6vi.i6vi_addr = *addr;
992 	i6vi.i6vi_dev = idev;
993 	rcu_read_unlock_bh();
994 
995 	err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
996 
997 	rcu_read_lock_bh();
998 	err = notifier_to_errno(err);
999 	if (err)
1000 		goto out2;
1001 
1002 	spin_lock(&addrconf_hash_lock);
1003 
1004 	/* Ignore adding duplicate addresses on an interface */
1005 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
1006 		ADBG("ipv6_add_addr: already assigned\n");
1007 		err = -EEXIST;
1008 		goto out;
1009 	}
1010 
1011 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
1012 
1013 	if (!ifa) {
1014 		ADBG("ipv6_add_addr: malloc failed\n");
1015 		err = -ENOBUFS;
1016 		goto out;
1017 	}
1018 
1019 	rt = addrconf_dst_alloc(idev, addr, false);
1020 	if (IS_ERR(rt)) {
1021 		err = PTR_ERR(rt);
1022 		goto out;
1023 	}
1024 
1025 	if (net->ipv6.devconf_all->disable_policy ||
1026 	    idev->cnf.disable_policy)
1027 		rt->dst.flags |= DST_NOPOLICY;
1028 
1029 	neigh_parms_data_state_setall(idev->nd_parms);
1030 
1031 	ifa->addr = *addr;
1032 	if (peer_addr)
1033 		ifa->peer_addr = *peer_addr;
1034 
1035 	spin_lock_init(&ifa->lock);
1036 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1037 	INIT_HLIST_NODE(&ifa->addr_lst);
1038 	ifa->scope = scope;
1039 	ifa->prefix_len = pfxlen;
1040 	ifa->flags = flags;
1041 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1042 	if (!(flags & IFA_F_NODAD))
1043 		ifa->flags |= IFA_F_TENTATIVE;
1044 	ifa->valid_lft = valid_lft;
1045 	ifa->prefered_lft = prefered_lft;
1046 	ifa->cstamp = ifa->tstamp = jiffies;
1047 	ifa->tokenized = false;
1048 
1049 	ifa->rt = rt;
1050 
1051 	ifa->idev = idev;
1052 	/* For caller */
1053 	refcount_set(&ifa->refcnt, 1);
1054 
1055 	/* Add to big hash table */
1056 	hash = inet6_addr_hash(addr);
1057 
1058 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1059 	spin_unlock(&addrconf_hash_lock);
1060 
1061 	write_lock(&idev->lock);
1062 	/* Add to inet6_dev unicast addr list. */
1063 	ipv6_link_dev_addr(idev, ifa);
1064 
1065 	if (ifa->flags&IFA_F_TEMPORARY) {
1066 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1067 		in6_ifa_hold(ifa);
1068 	}
1069 
1070 	in6_ifa_hold(ifa);
1071 	write_unlock(&idev->lock);
1072 out2:
1073 	rcu_read_unlock_bh();
1074 
1075 	if (likely(err == 0))
1076 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1077 	else {
1078 		kfree(ifa);
1079 		in6_dev_put(idev);
1080 		ifa = ERR_PTR(err);
1081 	}
1082 
1083 	return ifa;
1084 out:
1085 	spin_unlock(&addrconf_hash_lock);
1086 	goto out2;
1087 }
1088 
1089 enum cleanup_prefix_rt_t {
1090 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1091 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1092 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1093 };
1094 
1095 /*
1096  * Check, whether the prefix for ifp would still need a prefix route
1097  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1098  * constants.
1099  *
1100  * 1) we don't purge prefix if address was not permanent.
1101  *    prefix is managed by its own lifetime.
1102  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1103  * 3) if there are no addresses, delete prefix.
1104  * 4) if there are still other permanent address(es),
1105  *    corresponding prefix is still permanent.
1106  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1107  *    don't purge the prefix, assume user space is managing it.
1108  * 6) otherwise, update prefix lifetime to the
1109  *    longest valid lifetime among the corresponding
1110  *    addresses on the device.
1111  *    Note: subsequent RA will update lifetime.
1112  **/
1113 static enum cleanup_prefix_rt_t
1114 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1115 {
1116 	struct inet6_ifaddr *ifa;
1117 	struct inet6_dev *idev = ifp->idev;
1118 	unsigned long lifetime;
1119 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1120 
1121 	*expires = jiffies;
1122 
1123 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1124 		if (ifa == ifp)
1125 			continue;
1126 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1127 				       ifp->prefix_len))
1128 			continue;
1129 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1130 			return CLEANUP_PREFIX_RT_NOP;
1131 
1132 		action = CLEANUP_PREFIX_RT_EXPIRE;
1133 
1134 		spin_lock(&ifa->lock);
1135 
1136 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1137 		/*
1138 		 * Note: Because this address is
1139 		 * not permanent, lifetime <
1140 		 * LONG_MAX / HZ here.
1141 		 */
1142 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1143 			*expires = ifa->tstamp + lifetime * HZ;
1144 		spin_unlock(&ifa->lock);
1145 	}
1146 
1147 	return action;
1148 }
1149 
1150 static void
1151 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1152 {
1153 	struct rt6_info *rt;
1154 
1155 	rt = addrconf_get_prefix_route(&ifp->addr,
1156 				       ifp->prefix_len,
1157 				       ifp->idev->dev,
1158 				       0, RTF_GATEWAY | RTF_DEFAULT);
1159 	if (rt) {
1160 		if (del_rt)
1161 			ip6_del_rt(rt);
1162 		else {
1163 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1164 				rt6_set_expires(rt, expires);
1165 			ip6_rt_put(rt);
1166 		}
1167 	}
1168 }
1169 
1170 
1171 /* This function wants to get referenced ifp and releases it before return */
1172 
1173 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1174 {
1175 	int state;
1176 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1177 	unsigned long expires;
1178 
1179 	ASSERT_RTNL();
1180 
1181 	spin_lock_bh(&ifp->lock);
1182 	state = ifp->state;
1183 	ifp->state = INET6_IFADDR_STATE_DEAD;
1184 	spin_unlock_bh(&ifp->lock);
1185 
1186 	if (state == INET6_IFADDR_STATE_DEAD)
1187 		goto out;
1188 
1189 	spin_lock_bh(&addrconf_hash_lock);
1190 	hlist_del_init_rcu(&ifp->addr_lst);
1191 	spin_unlock_bh(&addrconf_hash_lock);
1192 
1193 	write_lock_bh(&ifp->idev->lock);
1194 
1195 	if (ifp->flags&IFA_F_TEMPORARY) {
1196 		list_del(&ifp->tmp_list);
1197 		if (ifp->ifpub) {
1198 			in6_ifa_put(ifp->ifpub);
1199 			ifp->ifpub = NULL;
1200 		}
1201 		__in6_ifa_put(ifp);
1202 	}
1203 
1204 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1205 		action = check_cleanup_prefix_route(ifp, &expires);
1206 
1207 	list_del_init(&ifp->if_list);
1208 	__in6_ifa_put(ifp);
1209 
1210 	write_unlock_bh(&ifp->idev->lock);
1211 
1212 	addrconf_del_dad_work(ifp);
1213 
1214 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1215 
1216 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1217 
1218 	if (action != CLEANUP_PREFIX_RT_NOP) {
1219 		cleanup_prefix_route(ifp, expires,
1220 			action == CLEANUP_PREFIX_RT_DEL);
1221 	}
1222 
1223 	/* clean up prefsrc entries */
1224 	rt6_remove_prefsrc(ifp);
1225 out:
1226 	in6_ifa_put(ifp);
1227 }
1228 
1229 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1230 {
1231 	struct inet6_dev *idev = ifp->idev;
1232 	struct in6_addr addr, *tmpaddr;
1233 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1234 	unsigned long regen_advance;
1235 	int tmp_plen;
1236 	int ret = 0;
1237 	u32 addr_flags;
1238 	unsigned long now = jiffies;
1239 	long max_desync_factor;
1240 	s32 cnf_temp_preferred_lft;
1241 
1242 	write_lock_bh(&idev->lock);
1243 	if (ift) {
1244 		spin_lock_bh(&ift->lock);
1245 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1246 		spin_unlock_bh(&ift->lock);
1247 		tmpaddr = &addr;
1248 	} else {
1249 		tmpaddr = NULL;
1250 	}
1251 retry:
1252 	in6_dev_hold(idev);
1253 	if (idev->cnf.use_tempaddr <= 0) {
1254 		write_unlock_bh(&idev->lock);
1255 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1256 		in6_dev_put(idev);
1257 		ret = -1;
1258 		goto out;
1259 	}
1260 	spin_lock_bh(&ifp->lock);
1261 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1262 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1263 		spin_unlock_bh(&ifp->lock);
1264 		write_unlock_bh(&idev->lock);
1265 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1266 			__func__);
1267 		in6_dev_put(idev);
1268 		ret = -1;
1269 		goto out;
1270 	}
1271 	in6_ifa_hold(ifp);
1272 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1273 	ipv6_try_regen_rndid(idev, tmpaddr);
1274 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1275 	age = (now - ifp->tstamp) / HZ;
1276 
1277 	regen_advance = idev->cnf.regen_max_retry *
1278 			idev->cnf.dad_transmits *
1279 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1280 
1281 	/* recalculate max_desync_factor each time and update
1282 	 * idev->desync_factor if it's larger
1283 	 */
1284 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1285 	max_desync_factor = min_t(__u32,
1286 				  idev->cnf.max_desync_factor,
1287 				  cnf_temp_preferred_lft - regen_advance);
1288 
1289 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1290 		if (max_desync_factor > 0) {
1291 			get_random_bytes(&idev->desync_factor,
1292 					 sizeof(idev->desync_factor));
1293 			idev->desync_factor %= max_desync_factor;
1294 		} else {
1295 			idev->desync_factor = 0;
1296 		}
1297 	}
1298 
1299 	tmp_valid_lft = min_t(__u32,
1300 			      ifp->valid_lft,
1301 			      idev->cnf.temp_valid_lft + age);
1302 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1303 			    idev->desync_factor;
1304 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1305 	tmp_plen = ifp->prefix_len;
1306 	tmp_tstamp = ifp->tstamp;
1307 	spin_unlock_bh(&ifp->lock);
1308 
1309 	write_unlock_bh(&idev->lock);
1310 
1311 	/* A temporary address is created only if this calculated Preferred
1312 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1313 	 * an implementation must not create a temporary address with a zero
1314 	 * Preferred Lifetime.
1315 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1316 	 * temporary addresses being generated.
1317 	 */
1318 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1319 	if (tmp_prefered_lft <= regen_advance + age) {
1320 		in6_ifa_put(ifp);
1321 		in6_dev_put(idev);
1322 		ret = -1;
1323 		goto out;
1324 	}
1325 
1326 	addr_flags = IFA_F_TEMPORARY;
1327 	/* set in addrconf_prefix_rcv() */
1328 	if (ifp->flags & IFA_F_OPTIMISTIC)
1329 		addr_flags |= IFA_F_OPTIMISTIC;
1330 
1331 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1332 			    ipv6_addr_scope(&addr), addr_flags,
1333 			    tmp_valid_lft, tmp_prefered_lft);
1334 	if (IS_ERR(ift)) {
1335 		in6_ifa_put(ifp);
1336 		in6_dev_put(idev);
1337 		pr_info("%s: retry temporary address regeneration\n", __func__);
1338 		tmpaddr = &addr;
1339 		write_lock_bh(&idev->lock);
1340 		goto retry;
1341 	}
1342 
1343 	spin_lock_bh(&ift->lock);
1344 	ift->ifpub = ifp;
1345 	ift->cstamp = now;
1346 	ift->tstamp = tmp_tstamp;
1347 	spin_unlock_bh(&ift->lock);
1348 
1349 	addrconf_dad_start(ift);
1350 	in6_ifa_put(ift);
1351 	in6_dev_put(idev);
1352 out:
1353 	return ret;
1354 }
1355 
1356 /*
1357  *	Choose an appropriate source address (RFC3484)
1358  */
1359 enum {
1360 	IPV6_SADDR_RULE_INIT = 0,
1361 	IPV6_SADDR_RULE_LOCAL,
1362 	IPV6_SADDR_RULE_SCOPE,
1363 	IPV6_SADDR_RULE_PREFERRED,
1364 #ifdef CONFIG_IPV6_MIP6
1365 	IPV6_SADDR_RULE_HOA,
1366 #endif
1367 	IPV6_SADDR_RULE_OIF,
1368 	IPV6_SADDR_RULE_LABEL,
1369 	IPV6_SADDR_RULE_PRIVACY,
1370 	IPV6_SADDR_RULE_ORCHID,
1371 	IPV6_SADDR_RULE_PREFIX,
1372 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1373 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1374 #endif
1375 	IPV6_SADDR_RULE_MAX
1376 };
1377 
1378 struct ipv6_saddr_score {
1379 	int			rule;
1380 	int			addr_type;
1381 	struct inet6_ifaddr	*ifa;
1382 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1383 	int			scopedist;
1384 	int			matchlen;
1385 };
1386 
1387 struct ipv6_saddr_dst {
1388 	const struct in6_addr *addr;
1389 	int ifindex;
1390 	int scope;
1391 	int label;
1392 	unsigned int prefs;
1393 };
1394 
1395 static inline int ipv6_saddr_preferred(int type)
1396 {
1397 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1398 		return 1;
1399 	return 0;
1400 }
1401 
1402 static bool ipv6_use_optimistic_addr(struct net *net,
1403 				     struct inet6_dev *idev)
1404 {
1405 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1406 	if (!idev)
1407 		return false;
1408 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1409 		return false;
1410 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1411 		return false;
1412 
1413 	return true;
1414 #else
1415 	return false;
1416 #endif
1417 }
1418 
1419 static int ipv6_get_saddr_eval(struct net *net,
1420 			       struct ipv6_saddr_score *score,
1421 			       struct ipv6_saddr_dst *dst,
1422 			       int i)
1423 {
1424 	int ret;
1425 
1426 	if (i <= score->rule) {
1427 		switch (i) {
1428 		case IPV6_SADDR_RULE_SCOPE:
1429 			ret = score->scopedist;
1430 			break;
1431 		case IPV6_SADDR_RULE_PREFIX:
1432 			ret = score->matchlen;
1433 			break;
1434 		default:
1435 			ret = !!test_bit(i, score->scorebits);
1436 		}
1437 		goto out;
1438 	}
1439 
1440 	switch (i) {
1441 	case IPV6_SADDR_RULE_INIT:
1442 		/* Rule 0: remember if hiscore is not ready yet */
1443 		ret = !!score->ifa;
1444 		break;
1445 	case IPV6_SADDR_RULE_LOCAL:
1446 		/* Rule 1: Prefer same address */
1447 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1448 		break;
1449 	case IPV6_SADDR_RULE_SCOPE:
1450 		/* Rule 2: Prefer appropriate scope
1451 		 *
1452 		 *      ret
1453 		 *       ^
1454 		 *    -1 |  d 15
1455 		 *    ---+--+-+---> scope
1456 		 *       |
1457 		 *       |             d is scope of the destination.
1458 		 *  B-d  |  \
1459 		 *       |   \      <- smaller scope is better if
1460 		 *  B-15 |    \        if scope is enough for destination.
1461 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1462 		 * d-C-1 | /
1463 		 *       |/         <- greater is better
1464 		 *   -C  /             if scope is not enough for destination.
1465 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1466 		 *
1467 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1468 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1469 		 * Assume B = 0 and we get C > 29.
1470 		 */
1471 		ret = __ipv6_addr_src_scope(score->addr_type);
1472 		if (ret >= dst->scope)
1473 			ret = -ret;
1474 		else
1475 			ret -= 128;	/* 30 is enough */
1476 		score->scopedist = ret;
1477 		break;
1478 	case IPV6_SADDR_RULE_PREFERRED:
1479 	    {
1480 		/* Rule 3: Avoid deprecated and optimistic addresses */
1481 		u8 avoid = IFA_F_DEPRECATED;
1482 
1483 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1484 			avoid |= IFA_F_OPTIMISTIC;
1485 		ret = ipv6_saddr_preferred(score->addr_type) ||
1486 		      !(score->ifa->flags & avoid);
1487 		break;
1488 	    }
1489 #ifdef CONFIG_IPV6_MIP6
1490 	case IPV6_SADDR_RULE_HOA:
1491 	    {
1492 		/* Rule 4: Prefer home address */
1493 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1494 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1495 		break;
1496 	    }
1497 #endif
1498 	case IPV6_SADDR_RULE_OIF:
1499 		/* Rule 5: Prefer outgoing interface */
1500 		ret = (!dst->ifindex ||
1501 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1502 		break;
1503 	case IPV6_SADDR_RULE_LABEL:
1504 		/* Rule 6: Prefer matching label */
1505 		ret = ipv6_addr_label(net,
1506 				      &score->ifa->addr, score->addr_type,
1507 				      score->ifa->idev->dev->ifindex) == dst->label;
1508 		break;
1509 	case IPV6_SADDR_RULE_PRIVACY:
1510 	    {
1511 		/* Rule 7: Prefer public address
1512 		 * Note: prefer temporary address if use_tempaddr >= 2
1513 		 */
1514 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1515 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1516 				score->ifa->idev->cnf.use_tempaddr >= 2;
1517 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1518 		break;
1519 	    }
1520 	case IPV6_SADDR_RULE_ORCHID:
1521 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1522 		 *	    non-ORCHID vs non-ORCHID
1523 		 */
1524 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1525 			ipv6_addr_orchid(dst->addr));
1526 		break;
1527 	case IPV6_SADDR_RULE_PREFIX:
1528 		/* Rule 8: Use longest matching prefix */
1529 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1530 		if (ret > score->ifa->prefix_len)
1531 			ret = score->ifa->prefix_len;
1532 		score->matchlen = ret;
1533 		break;
1534 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1535 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1536 		/* Optimistic addresses still have lower precedence than other
1537 		 * preferred addresses.
1538 		 */
1539 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1540 		break;
1541 #endif
1542 	default:
1543 		ret = 0;
1544 	}
1545 
1546 	if (ret)
1547 		__set_bit(i, score->scorebits);
1548 	score->rule = i;
1549 out:
1550 	return ret;
1551 }
1552 
1553 static int __ipv6_dev_get_saddr(struct net *net,
1554 				struct ipv6_saddr_dst *dst,
1555 				struct inet6_dev *idev,
1556 				struct ipv6_saddr_score *scores,
1557 				int hiscore_idx)
1558 {
1559 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1560 
1561 	read_lock_bh(&idev->lock);
1562 	list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1563 		int i;
1564 
1565 		/*
1566 		 * - Tentative Address (RFC2462 section 5.4)
1567 		 *  - A tentative address is not considered
1568 		 *    "assigned to an interface" in the traditional
1569 		 *    sense, unless it is also flagged as optimistic.
1570 		 * - Candidate Source Address (section 4)
1571 		 *  - In any case, anycast addresses, multicast
1572 		 *    addresses, and the unspecified address MUST
1573 		 *    NOT be included in a candidate set.
1574 		 */
1575 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1576 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1577 			continue;
1578 
1579 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1580 
1581 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1582 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1583 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1584 					    idev->dev->name);
1585 			continue;
1586 		}
1587 
1588 		score->rule = -1;
1589 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1590 
1591 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1592 			int minihiscore, miniscore;
1593 
1594 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1595 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1596 
1597 			if (minihiscore > miniscore) {
1598 				if (i == IPV6_SADDR_RULE_SCOPE &&
1599 				    score->scopedist > 0) {
1600 					/*
1601 					 * special case:
1602 					 * each remaining entry
1603 					 * has too small (not enough)
1604 					 * scope, because ifa entries
1605 					 * are sorted by their scope
1606 					 * values.
1607 					 */
1608 					goto out;
1609 				}
1610 				break;
1611 			} else if (minihiscore < miniscore) {
1612 				if (hiscore->ifa)
1613 					in6_ifa_put(hiscore->ifa);
1614 
1615 				in6_ifa_hold(score->ifa);
1616 
1617 				swap(hiscore, score);
1618 				hiscore_idx = 1 - hiscore_idx;
1619 
1620 				/* restore our iterator */
1621 				score->ifa = hiscore->ifa;
1622 
1623 				break;
1624 			}
1625 		}
1626 	}
1627 out:
1628 	read_unlock_bh(&idev->lock);
1629 	return hiscore_idx;
1630 }
1631 
1632 static int ipv6_get_saddr_master(struct net *net,
1633 				 const struct net_device *dst_dev,
1634 				 const struct net_device *master,
1635 				 struct ipv6_saddr_dst *dst,
1636 				 struct ipv6_saddr_score *scores,
1637 				 int hiscore_idx)
1638 {
1639 	struct inet6_dev *idev;
1640 
1641 	idev = __in6_dev_get(dst_dev);
1642 	if (idev)
1643 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1644 						   scores, hiscore_idx);
1645 
1646 	idev = __in6_dev_get(master);
1647 	if (idev)
1648 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1649 						   scores, hiscore_idx);
1650 
1651 	return hiscore_idx;
1652 }
1653 
1654 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1655 		       const struct in6_addr *daddr, unsigned int prefs,
1656 		       struct in6_addr *saddr)
1657 {
1658 	struct ipv6_saddr_score scores[2], *hiscore;
1659 	struct ipv6_saddr_dst dst;
1660 	struct inet6_dev *idev;
1661 	struct net_device *dev;
1662 	int dst_type;
1663 	bool use_oif_addr = false;
1664 	int hiscore_idx = 0;
1665 
1666 	dst_type = __ipv6_addr_type(daddr);
1667 	dst.addr = daddr;
1668 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1669 	dst.scope = __ipv6_addr_src_scope(dst_type);
1670 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1671 	dst.prefs = prefs;
1672 
1673 	scores[hiscore_idx].rule = -1;
1674 	scores[hiscore_idx].ifa = NULL;
1675 
1676 	rcu_read_lock();
1677 
1678 	/* Candidate Source Address (section 4)
1679 	 *  - multicast and link-local destination address,
1680 	 *    the set of candidate source address MUST only
1681 	 *    include addresses assigned to interfaces
1682 	 *    belonging to the same link as the outgoing
1683 	 *    interface.
1684 	 * (- For site-local destination addresses, the
1685 	 *    set of candidate source addresses MUST only
1686 	 *    include addresses assigned to interfaces
1687 	 *    belonging to the same site as the outgoing
1688 	 *    interface.)
1689 	 *  - "It is RECOMMENDED that the candidate source addresses
1690 	 *    be the set of unicast addresses assigned to the
1691 	 *    interface that will be used to send to the destination
1692 	 *    (the 'outgoing' interface)." (RFC 6724)
1693 	 */
1694 	if (dst_dev) {
1695 		idev = __in6_dev_get(dst_dev);
1696 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1697 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1698 		    (idev && idev->cnf.use_oif_addrs_only)) {
1699 			use_oif_addr = true;
1700 		}
1701 	}
1702 
1703 	if (use_oif_addr) {
1704 		if (idev)
1705 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1706 	} else {
1707 		const struct net_device *master;
1708 		int master_idx = 0;
1709 
1710 		/* if dst_dev exists and is enslaved to an L3 device, then
1711 		 * prefer addresses from dst_dev and then the master over
1712 		 * any other enslaved devices in the L3 domain.
1713 		 */
1714 		master = l3mdev_master_dev_rcu(dst_dev);
1715 		if (master) {
1716 			master_idx = master->ifindex;
1717 
1718 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1719 							    master, &dst,
1720 							    scores, hiscore_idx);
1721 
1722 			if (scores[hiscore_idx].ifa)
1723 				goto out;
1724 		}
1725 
1726 		for_each_netdev_rcu(net, dev) {
1727 			/* only consider addresses on devices in the
1728 			 * same L3 domain
1729 			 */
1730 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1731 				continue;
1732 			idev = __in6_dev_get(dev);
1733 			if (!idev)
1734 				continue;
1735 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1736 		}
1737 	}
1738 
1739 out:
1740 	rcu_read_unlock();
1741 
1742 	hiscore = &scores[hiscore_idx];
1743 	if (!hiscore->ifa)
1744 		return -EADDRNOTAVAIL;
1745 
1746 	*saddr = hiscore->ifa->addr;
1747 	in6_ifa_put(hiscore->ifa);
1748 	return 0;
1749 }
1750 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1751 
1752 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1753 		      u32 banned_flags)
1754 {
1755 	struct inet6_ifaddr *ifp;
1756 	int err = -EADDRNOTAVAIL;
1757 
1758 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1759 		if (ifp->scope > IFA_LINK)
1760 			break;
1761 		if (ifp->scope == IFA_LINK &&
1762 		    !(ifp->flags & banned_flags)) {
1763 			*addr = ifp->addr;
1764 			err = 0;
1765 			break;
1766 		}
1767 	}
1768 	return err;
1769 }
1770 
1771 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1772 		    u32 banned_flags)
1773 {
1774 	struct inet6_dev *idev;
1775 	int err = -EADDRNOTAVAIL;
1776 
1777 	rcu_read_lock();
1778 	idev = __in6_dev_get(dev);
1779 	if (idev) {
1780 		read_lock_bh(&idev->lock);
1781 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1782 		read_unlock_bh(&idev->lock);
1783 	}
1784 	rcu_read_unlock();
1785 	return err;
1786 }
1787 
1788 static int ipv6_count_addresses(struct inet6_dev *idev)
1789 {
1790 	int cnt = 0;
1791 	struct inet6_ifaddr *ifp;
1792 
1793 	read_lock_bh(&idev->lock);
1794 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1795 		cnt++;
1796 	read_unlock_bh(&idev->lock);
1797 	return cnt;
1798 }
1799 
1800 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1801 		  const struct net_device *dev, int strict)
1802 {
1803 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1804 }
1805 EXPORT_SYMBOL(ipv6_chk_addr);
1806 
1807 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1808 			    const struct net_device *dev, int strict,
1809 			    u32 banned_flags)
1810 {
1811 	struct inet6_ifaddr *ifp;
1812 	unsigned int hash = inet6_addr_hash(addr);
1813 	u32 ifp_flags;
1814 
1815 	rcu_read_lock_bh();
1816 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1817 		if (!net_eq(dev_net(ifp->idev->dev), net))
1818 			continue;
1819 		/* Decouple optimistic from tentative for evaluation here.
1820 		 * Ban optimistic addresses explicitly, when required.
1821 		 */
1822 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1823 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1824 			    : ifp->flags;
1825 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1826 		    !(ifp_flags&banned_flags) &&
1827 		    (!dev || ifp->idev->dev == dev ||
1828 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1829 			rcu_read_unlock_bh();
1830 			return 1;
1831 		}
1832 	}
1833 
1834 	rcu_read_unlock_bh();
1835 	return 0;
1836 }
1837 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1838 
1839 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1840 			       struct net_device *dev)
1841 {
1842 	unsigned int hash = inet6_addr_hash(addr);
1843 	struct inet6_ifaddr *ifp;
1844 
1845 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1846 		if (!net_eq(dev_net(ifp->idev->dev), net))
1847 			continue;
1848 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1849 			if (!dev || ifp->idev->dev == dev)
1850 				return true;
1851 		}
1852 	}
1853 	return false;
1854 }
1855 
1856 /* Compares an address/prefix_len with addresses on device @dev.
1857  * If one is found it returns true.
1858  */
1859 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1860 	const unsigned int prefix_len, struct net_device *dev)
1861 {
1862 	struct inet6_dev *idev;
1863 	struct inet6_ifaddr *ifa;
1864 	bool ret = false;
1865 
1866 	rcu_read_lock();
1867 	idev = __in6_dev_get(dev);
1868 	if (idev) {
1869 		read_lock_bh(&idev->lock);
1870 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1871 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1872 			if (ret)
1873 				break;
1874 		}
1875 		read_unlock_bh(&idev->lock);
1876 	}
1877 	rcu_read_unlock();
1878 
1879 	return ret;
1880 }
1881 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1882 
1883 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1884 {
1885 	struct inet6_dev *idev;
1886 	struct inet6_ifaddr *ifa;
1887 	int	onlink;
1888 
1889 	onlink = 0;
1890 	rcu_read_lock();
1891 	idev = __in6_dev_get(dev);
1892 	if (idev) {
1893 		read_lock_bh(&idev->lock);
1894 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1895 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1896 						   ifa->prefix_len);
1897 			if (onlink)
1898 				break;
1899 		}
1900 		read_unlock_bh(&idev->lock);
1901 	}
1902 	rcu_read_unlock();
1903 	return onlink;
1904 }
1905 EXPORT_SYMBOL(ipv6_chk_prefix);
1906 
1907 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1908 				     struct net_device *dev, int strict)
1909 {
1910 	struct inet6_ifaddr *ifp, *result = NULL;
1911 	unsigned int hash = inet6_addr_hash(addr);
1912 
1913 	rcu_read_lock_bh();
1914 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1915 		if (!net_eq(dev_net(ifp->idev->dev), net))
1916 			continue;
1917 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1918 			if (!dev || ifp->idev->dev == dev ||
1919 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1920 				result = ifp;
1921 				in6_ifa_hold(ifp);
1922 				break;
1923 			}
1924 		}
1925 	}
1926 	rcu_read_unlock_bh();
1927 
1928 	return result;
1929 }
1930 
1931 /* Gets referenced address, destroys ifaddr */
1932 
1933 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1934 {
1935 	if (dad_failed)
1936 		ifp->flags |= IFA_F_DADFAILED;
1937 
1938 	if (ifp->flags&IFA_F_TEMPORARY) {
1939 		struct inet6_ifaddr *ifpub;
1940 		spin_lock_bh(&ifp->lock);
1941 		ifpub = ifp->ifpub;
1942 		if (ifpub) {
1943 			in6_ifa_hold(ifpub);
1944 			spin_unlock_bh(&ifp->lock);
1945 			ipv6_create_tempaddr(ifpub, ifp);
1946 			in6_ifa_put(ifpub);
1947 		} else {
1948 			spin_unlock_bh(&ifp->lock);
1949 		}
1950 		ipv6_del_addr(ifp);
1951 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1952 		spin_lock_bh(&ifp->lock);
1953 		addrconf_del_dad_work(ifp);
1954 		ifp->flags |= IFA_F_TENTATIVE;
1955 		spin_unlock_bh(&ifp->lock);
1956 		if (dad_failed)
1957 			ipv6_ifa_notify(0, ifp);
1958 		in6_ifa_put(ifp);
1959 	} else {
1960 		ipv6_del_addr(ifp);
1961 	}
1962 }
1963 
1964 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1965 {
1966 	int err = -ENOENT;
1967 
1968 	spin_lock_bh(&ifp->lock);
1969 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1970 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1971 		err = 0;
1972 	}
1973 	spin_unlock_bh(&ifp->lock);
1974 
1975 	return err;
1976 }
1977 
1978 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1979 {
1980 	struct inet6_dev *idev = ifp->idev;
1981 	struct net *net = dev_net(ifp->idev->dev);
1982 
1983 	if (addrconf_dad_end(ifp)) {
1984 		in6_ifa_put(ifp);
1985 		return;
1986 	}
1987 
1988 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1989 			     ifp->idev->dev->name, &ifp->addr);
1990 
1991 	spin_lock_bh(&ifp->lock);
1992 
1993 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1994 		int scope = ifp->scope;
1995 		u32 flags = ifp->flags;
1996 		struct in6_addr new_addr;
1997 		struct inet6_ifaddr *ifp2;
1998 		u32 valid_lft, preferred_lft;
1999 		int pfxlen = ifp->prefix_len;
2000 		int retries = ifp->stable_privacy_retry + 1;
2001 
2002 		if (retries > net->ipv6.sysctl.idgen_retries) {
2003 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2004 					     ifp->idev->dev->name);
2005 			goto errdad;
2006 		}
2007 
2008 		new_addr = ifp->addr;
2009 		if (ipv6_generate_stable_address(&new_addr, retries,
2010 						 idev))
2011 			goto errdad;
2012 
2013 		valid_lft = ifp->valid_lft;
2014 		preferred_lft = ifp->prefered_lft;
2015 
2016 		spin_unlock_bh(&ifp->lock);
2017 
2018 		if (idev->cnf.max_addresses &&
2019 		    ipv6_count_addresses(idev) >=
2020 		    idev->cnf.max_addresses)
2021 			goto lock_errdad;
2022 
2023 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2024 				     ifp->idev->dev->name);
2025 
2026 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2027 				     scope, flags, valid_lft,
2028 				     preferred_lft);
2029 		if (IS_ERR(ifp2))
2030 			goto lock_errdad;
2031 
2032 		spin_lock_bh(&ifp2->lock);
2033 		ifp2->stable_privacy_retry = retries;
2034 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2035 		spin_unlock_bh(&ifp2->lock);
2036 
2037 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2038 		in6_ifa_put(ifp2);
2039 lock_errdad:
2040 		spin_lock_bh(&ifp->lock);
2041 	}
2042 
2043 errdad:
2044 	/* transition from _POSTDAD to _ERRDAD */
2045 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2046 	spin_unlock_bh(&ifp->lock);
2047 
2048 	addrconf_mod_dad_work(ifp, 0);
2049 	in6_ifa_put(ifp);
2050 }
2051 
2052 /* Join to solicited addr multicast group.
2053  * caller must hold RTNL */
2054 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2055 {
2056 	struct in6_addr maddr;
2057 
2058 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2059 		return;
2060 
2061 	addrconf_addr_solict_mult(addr, &maddr);
2062 	ipv6_dev_mc_inc(dev, &maddr);
2063 }
2064 
2065 /* caller must hold RTNL */
2066 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2067 {
2068 	struct in6_addr maddr;
2069 
2070 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2071 		return;
2072 
2073 	addrconf_addr_solict_mult(addr, &maddr);
2074 	__ipv6_dev_mc_dec(idev, &maddr);
2075 }
2076 
2077 /* caller must hold RTNL */
2078 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2079 {
2080 	struct in6_addr addr;
2081 
2082 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2083 		return;
2084 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2085 	if (ipv6_addr_any(&addr))
2086 		return;
2087 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2088 }
2089 
2090 /* caller must hold RTNL */
2091 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2092 {
2093 	struct in6_addr addr;
2094 
2095 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2096 		return;
2097 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2098 	if (ipv6_addr_any(&addr))
2099 		return;
2100 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2101 }
2102 
2103 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2104 {
2105 	switch (dev->addr_len) {
2106 	case ETH_ALEN:
2107 		memcpy(eui, dev->dev_addr, 3);
2108 		eui[3] = 0xFF;
2109 		eui[4] = 0xFE;
2110 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2111 		break;
2112 	case EUI64_ADDR_LEN:
2113 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2114 		eui[0] ^= 2;
2115 		break;
2116 	default:
2117 		return -1;
2118 	}
2119 
2120 	return 0;
2121 }
2122 
2123 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2124 {
2125 	union fwnet_hwaddr *ha;
2126 
2127 	if (dev->addr_len != FWNET_ALEN)
2128 		return -1;
2129 
2130 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2131 
2132 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2133 	eui[0] ^= 2;
2134 	return 0;
2135 }
2136 
2137 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2138 {
2139 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2140 	if (dev->addr_len != ARCNET_ALEN)
2141 		return -1;
2142 	memset(eui, 0, 7);
2143 	eui[7] = *(u8 *)dev->dev_addr;
2144 	return 0;
2145 }
2146 
2147 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2148 {
2149 	if (dev->addr_len != INFINIBAND_ALEN)
2150 		return -1;
2151 	memcpy(eui, dev->dev_addr + 12, 8);
2152 	eui[0] |= 2;
2153 	return 0;
2154 }
2155 
2156 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2157 {
2158 	if (addr == 0)
2159 		return -1;
2160 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2161 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2162 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2163 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2164 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2165 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2166 	eui[1] = 0;
2167 	eui[2] = 0x5E;
2168 	eui[3] = 0xFE;
2169 	memcpy(eui + 4, &addr, 4);
2170 	return 0;
2171 }
2172 
2173 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2174 {
2175 	if (dev->priv_flags & IFF_ISATAP)
2176 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2177 	return -1;
2178 }
2179 
2180 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2181 {
2182 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2183 }
2184 
2185 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2186 {
2187 	memcpy(eui, dev->perm_addr, 3);
2188 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2189 	eui[3] = 0xFF;
2190 	eui[4] = 0xFE;
2191 	eui[0] ^= 2;
2192 	return 0;
2193 }
2194 
2195 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2196 {
2197 	switch (dev->type) {
2198 	case ARPHRD_ETHER:
2199 	case ARPHRD_FDDI:
2200 		return addrconf_ifid_eui48(eui, dev);
2201 	case ARPHRD_ARCNET:
2202 		return addrconf_ifid_arcnet(eui, dev);
2203 	case ARPHRD_INFINIBAND:
2204 		return addrconf_ifid_infiniband(eui, dev);
2205 	case ARPHRD_SIT:
2206 		return addrconf_ifid_sit(eui, dev);
2207 	case ARPHRD_IPGRE:
2208 	case ARPHRD_TUNNEL:
2209 		return addrconf_ifid_gre(eui, dev);
2210 	case ARPHRD_6LOWPAN:
2211 		return addrconf_ifid_6lowpan(eui, dev);
2212 	case ARPHRD_IEEE1394:
2213 		return addrconf_ifid_ieee1394(eui, dev);
2214 	case ARPHRD_TUNNEL6:
2215 	case ARPHRD_IP6GRE:
2216 		return addrconf_ifid_ip6tnl(eui, dev);
2217 	}
2218 	return -1;
2219 }
2220 
2221 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2222 {
2223 	int err = -1;
2224 	struct inet6_ifaddr *ifp;
2225 
2226 	read_lock_bh(&idev->lock);
2227 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2228 		if (ifp->scope > IFA_LINK)
2229 			break;
2230 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2231 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2232 			err = 0;
2233 			break;
2234 		}
2235 	}
2236 	read_unlock_bh(&idev->lock);
2237 	return err;
2238 }
2239 
2240 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2241 static void ipv6_regen_rndid(struct inet6_dev *idev)
2242 {
2243 regen:
2244 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2245 	idev->rndid[0] &= ~0x02;
2246 
2247 	/*
2248 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2249 	 * check if generated address is not inappropriate
2250 	 *
2251 	 *  - Reserved subnet anycast (RFC 2526)
2252 	 *	11111101 11....11 1xxxxxxx
2253 	 *  - ISATAP (RFC4214) 6.1
2254 	 *	00-00-5E-FE-xx-xx-xx-xx
2255 	 *  - value 0
2256 	 *  - XXX: already assigned to an address on the device
2257 	 */
2258 	if (idev->rndid[0] == 0xfd &&
2259 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2260 	    (idev->rndid[7]&0x80))
2261 		goto regen;
2262 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2263 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2264 			goto regen;
2265 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2266 			goto regen;
2267 	}
2268 }
2269 
2270 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2271 {
2272 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2273 		ipv6_regen_rndid(idev);
2274 }
2275 
2276 /*
2277  *	Add prefix route.
2278  */
2279 
2280 static void
2281 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2282 		      unsigned long expires, u32 flags)
2283 {
2284 	struct fib6_config cfg = {
2285 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2286 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2287 		.fc_ifindex = dev->ifindex,
2288 		.fc_expires = expires,
2289 		.fc_dst_len = plen,
2290 		.fc_flags = RTF_UP | flags,
2291 		.fc_nlinfo.nl_net = dev_net(dev),
2292 		.fc_protocol = RTPROT_KERNEL,
2293 	};
2294 
2295 	cfg.fc_dst = *pfx;
2296 
2297 	/* Prevent useless cloning on PtP SIT.
2298 	   This thing is done here expecting that the whole
2299 	   class of non-broadcast devices need not cloning.
2300 	 */
2301 #if IS_ENABLED(CONFIG_IPV6_SIT)
2302 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2303 		cfg.fc_flags |= RTF_NONEXTHOP;
2304 #endif
2305 
2306 	ip6_route_add(&cfg, NULL);
2307 }
2308 
2309 
2310 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2311 						  int plen,
2312 						  const struct net_device *dev,
2313 						  u32 flags, u32 noflags)
2314 {
2315 	struct fib6_node *fn;
2316 	struct rt6_info *rt = NULL;
2317 	struct fib6_table *table;
2318 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2319 
2320 	table = fib6_get_table(dev_net(dev), tb_id);
2321 	if (!table)
2322 		return NULL;
2323 
2324 	read_lock_bh(&table->tb6_lock);
2325 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2326 	if (!fn)
2327 		goto out;
2328 
2329 	noflags |= RTF_CACHE;
2330 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2331 		if (rt->dst.dev->ifindex != dev->ifindex)
2332 			continue;
2333 		if ((rt->rt6i_flags & flags) != flags)
2334 			continue;
2335 		if ((rt->rt6i_flags & noflags) != 0)
2336 			continue;
2337 		dst_hold(&rt->dst);
2338 		break;
2339 	}
2340 out:
2341 	read_unlock_bh(&table->tb6_lock);
2342 	return rt;
2343 }
2344 
2345 
2346 /* Create "default" multicast route to the interface */
2347 
2348 static void addrconf_add_mroute(struct net_device *dev)
2349 {
2350 	struct fib6_config cfg = {
2351 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2352 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2353 		.fc_ifindex = dev->ifindex,
2354 		.fc_dst_len = 8,
2355 		.fc_flags = RTF_UP,
2356 		.fc_nlinfo.nl_net = dev_net(dev),
2357 	};
2358 
2359 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2360 
2361 	ip6_route_add(&cfg, NULL);
2362 }
2363 
2364 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2365 {
2366 	struct inet6_dev *idev;
2367 
2368 	ASSERT_RTNL();
2369 
2370 	idev = ipv6_find_idev(dev);
2371 	if (!idev)
2372 		return ERR_PTR(-ENOBUFS);
2373 
2374 	if (idev->cnf.disable_ipv6)
2375 		return ERR_PTR(-EACCES);
2376 
2377 	/* Add default multicast route */
2378 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2379 		addrconf_add_mroute(dev);
2380 
2381 	return idev;
2382 }
2383 
2384 static void manage_tempaddrs(struct inet6_dev *idev,
2385 			     struct inet6_ifaddr *ifp,
2386 			     __u32 valid_lft, __u32 prefered_lft,
2387 			     bool create, unsigned long now)
2388 {
2389 	u32 flags;
2390 	struct inet6_ifaddr *ift;
2391 
2392 	read_lock_bh(&idev->lock);
2393 	/* update all temporary addresses in the list */
2394 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2395 		int age, max_valid, max_prefered;
2396 
2397 		if (ifp != ift->ifpub)
2398 			continue;
2399 
2400 		/* RFC 4941 section 3.3:
2401 		 * If a received option will extend the lifetime of a public
2402 		 * address, the lifetimes of temporary addresses should
2403 		 * be extended, subject to the overall constraint that no
2404 		 * temporary addresses should ever remain "valid" or "preferred"
2405 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2406 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2407 		 */
2408 		age = (now - ift->cstamp) / HZ;
2409 		max_valid = idev->cnf.temp_valid_lft - age;
2410 		if (max_valid < 0)
2411 			max_valid = 0;
2412 
2413 		max_prefered = idev->cnf.temp_prefered_lft -
2414 			       idev->desync_factor - age;
2415 		if (max_prefered < 0)
2416 			max_prefered = 0;
2417 
2418 		if (valid_lft > max_valid)
2419 			valid_lft = max_valid;
2420 
2421 		if (prefered_lft > max_prefered)
2422 			prefered_lft = max_prefered;
2423 
2424 		spin_lock(&ift->lock);
2425 		flags = ift->flags;
2426 		ift->valid_lft = valid_lft;
2427 		ift->prefered_lft = prefered_lft;
2428 		ift->tstamp = now;
2429 		if (prefered_lft > 0)
2430 			ift->flags &= ~IFA_F_DEPRECATED;
2431 
2432 		spin_unlock(&ift->lock);
2433 		if (!(flags&IFA_F_TENTATIVE))
2434 			ipv6_ifa_notify(0, ift);
2435 	}
2436 
2437 	if ((create || list_empty(&idev->tempaddr_list)) &&
2438 	    idev->cnf.use_tempaddr > 0) {
2439 		/* When a new public address is created as described
2440 		 * in [ADDRCONF], also create a new temporary address.
2441 		 * Also create a temporary address if it's enabled but
2442 		 * no temporary address currently exists.
2443 		 */
2444 		read_unlock_bh(&idev->lock);
2445 		ipv6_create_tempaddr(ifp, NULL);
2446 	} else {
2447 		read_unlock_bh(&idev->lock);
2448 	}
2449 }
2450 
2451 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2452 {
2453 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2454 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2455 }
2456 
2457 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2458 				 const struct prefix_info *pinfo,
2459 				 struct inet6_dev *in6_dev,
2460 				 const struct in6_addr *addr, int addr_type,
2461 				 u32 addr_flags, bool sllao, bool tokenized,
2462 				 __u32 valid_lft, u32 prefered_lft)
2463 {
2464 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2465 	int create = 0, update_lft = 0;
2466 
2467 	if (!ifp && valid_lft) {
2468 		int max_addresses = in6_dev->cnf.max_addresses;
2469 
2470 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2471 		if ((net->ipv6.devconf_all->optimistic_dad ||
2472 		     in6_dev->cnf.optimistic_dad) &&
2473 		    !net->ipv6.devconf_all->forwarding && sllao)
2474 			addr_flags |= IFA_F_OPTIMISTIC;
2475 #endif
2476 
2477 		/* Do not allow to create too much of autoconfigured
2478 		 * addresses; this would be too easy way to crash kernel.
2479 		 */
2480 		if (!max_addresses ||
2481 		    ipv6_count_addresses(in6_dev) < max_addresses)
2482 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2483 					    pinfo->prefix_len,
2484 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2485 					    addr_flags, valid_lft,
2486 					    prefered_lft);
2487 
2488 		if (IS_ERR_OR_NULL(ifp))
2489 			return -1;
2490 
2491 		update_lft = 0;
2492 		create = 1;
2493 		spin_lock_bh(&ifp->lock);
2494 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2495 		ifp->cstamp = jiffies;
2496 		ifp->tokenized = tokenized;
2497 		spin_unlock_bh(&ifp->lock);
2498 		addrconf_dad_start(ifp);
2499 	}
2500 
2501 	if (ifp) {
2502 		u32 flags;
2503 		unsigned long now;
2504 		u32 stored_lft;
2505 
2506 		/* update lifetime (RFC2462 5.5.3 e) */
2507 		spin_lock_bh(&ifp->lock);
2508 		now = jiffies;
2509 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2510 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2511 		else
2512 			stored_lft = 0;
2513 		if (!update_lft && !create && stored_lft) {
2514 			const u32 minimum_lft = min_t(u32,
2515 				stored_lft, MIN_VALID_LIFETIME);
2516 			valid_lft = max(valid_lft, minimum_lft);
2517 
2518 			/* RFC4862 Section 5.5.3e:
2519 			 * "Note that the preferred lifetime of the
2520 			 *  corresponding address is always reset to
2521 			 *  the Preferred Lifetime in the received
2522 			 *  Prefix Information option, regardless of
2523 			 *  whether the valid lifetime is also reset or
2524 			 *  ignored."
2525 			 *
2526 			 * So we should always update prefered_lft here.
2527 			 */
2528 			update_lft = 1;
2529 		}
2530 
2531 		if (update_lft) {
2532 			ifp->valid_lft = valid_lft;
2533 			ifp->prefered_lft = prefered_lft;
2534 			ifp->tstamp = now;
2535 			flags = ifp->flags;
2536 			ifp->flags &= ~IFA_F_DEPRECATED;
2537 			spin_unlock_bh(&ifp->lock);
2538 
2539 			if (!(flags&IFA_F_TENTATIVE))
2540 				ipv6_ifa_notify(0, ifp);
2541 		} else
2542 			spin_unlock_bh(&ifp->lock);
2543 
2544 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2545 				 create, now);
2546 
2547 		in6_ifa_put(ifp);
2548 		addrconf_verify();
2549 	}
2550 
2551 	return 0;
2552 }
2553 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2554 
2555 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2556 {
2557 	struct prefix_info *pinfo;
2558 	__u32 valid_lft;
2559 	__u32 prefered_lft;
2560 	int addr_type, err;
2561 	u32 addr_flags = 0;
2562 	struct inet6_dev *in6_dev;
2563 	struct net *net = dev_net(dev);
2564 
2565 	pinfo = (struct prefix_info *) opt;
2566 
2567 	if (len < sizeof(struct prefix_info)) {
2568 		ADBG("addrconf: prefix option too short\n");
2569 		return;
2570 	}
2571 
2572 	/*
2573 	 *	Validation checks ([ADDRCONF], page 19)
2574 	 */
2575 
2576 	addr_type = ipv6_addr_type(&pinfo->prefix);
2577 
2578 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2579 		return;
2580 
2581 	valid_lft = ntohl(pinfo->valid);
2582 	prefered_lft = ntohl(pinfo->prefered);
2583 
2584 	if (prefered_lft > valid_lft) {
2585 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2586 		return;
2587 	}
2588 
2589 	in6_dev = in6_dev_get(dev);
2590 
2591 	if (!in6_dev) {
2592 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2593 				    dev->name);
2594 		return;
2595 	}
2596 
2597 	/*
2598 	 *	Two things going on here:
2599 	 *	1) Add routes for on-link prefixes
2600 	 *	2) Configure prefixes with the auto flag set
2601 	 */
2602 
2603 	if (pinfo->onlink) {
2604 		struct rt6_info *rt;
2605 		unsigned long rt_expires;
2606 
2607 		/* Avoid arithmetic overflow. Really, we could
2608 		 * save rt_expires in seconds, likely valid_lft,
2609 		 * but it would require division in fib gc, that it
2610 		 * not good.
2611 		 */
2612 		if (HZ > USER_HZ)
2613 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2614 		else
2615 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2616 
2617 		if (addrconf_finite_timeout(rt_expires))
2618 			rt_expires *= HZ;
2619 
2620 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2621 					       pinfo->prefix_len,
2622 					       dev,
2623 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2624 					       RTF_GATEWAY | RTF_DEFAULT);
2625 
2626 		if (rt) {
2627 			/* Autoconf prefix route */
2628 			if (valid_lft == 0) {
2629 				ip6_del_rt(rt);
2630 				rt = NULL;
2631 			} else if (addrconf_finite_timeout(rt_expires)) {
2632 				/* not infinity */
2633 				rt6_set_expires(rt, jiffies + rt_expires);
2634 			} else {
2635 				rt6_clean_expires(rt);
2636 			}
2637 		} else if (valid_lft) {
2638 			clock_t expires = 0;
2639 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2640 			if (addrconf_finite_timeout(rt_expires)) {
2641 				/* not infinity */
2642 				flags |= RTF_EXPIRES;
2643 				expires = jiffies_to_clock_t(rt_expires);
2644 			}
2645 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2646 					      dev, expires, flags);
2647 		}
2648 		ip6_rt_put(rt);
2649 	}
2650 
2651 	/* Try to figure out our local address for this prefix */
2652 
2653 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2654 		struct in6_addr addr;
2655 		bool tokenized = false, dev_addr_generated = false;
2656 
2657 		if (pinfo->prefix_len == 64) {
2658 			memcpy(&addr, &pinfo->prefix, 8);
2659 
2660 			if (!ipv6_addr_any(&in6_dev->token)) {
2661 				read_lock_bh(&in6_dev->lock);
2662 				memcpy(addr.s6_addr + 8,
2663 				       in6_dev->token.s6_addr + 8, 8);
2664 				read_unlock_bh(&in6_dev->lock);
2665 				tokenized = true;
2666 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2667 				   !ipv6_generate_stable_address(&addr, 0,
2668 								 in6_dev)) {
2669 				addr_flags |= IFA_F_STABLE_PRIVACY;
2670 				goto ok;
2671 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2672 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2673 				goto put;
2674 			} else {
2675 				dev_addr_generated = true;
2676 			}
2677 			goto ok;
2678 		}
2679 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2680 				    pinfo->prefix_len);
2681 		goto put;
2682 
2683 ok:
2684 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2685 						   &addr, addr_type,
2686 						   addr_flags, sllao,
2687 						   tokenized, valid_lft,
2688 						   prefered_lft);
2689 		if (err)
2690 			goto put;
2691 
2692 		/* Ignore error case here because previous prefix add addr was
2693 		 * successful which will be notified.
2694 		 */
2695 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2696 					      addr_type, addr_flags, sllao,
2697 					      tokenized, valid_lft,
2698 					      prefered_lft,
2699 					      dev_addr_generated);
2700 	}
2701 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2702 put:
2703 	in6_dev_put(in6_dev);
2704 }
2705 
2706 /*
2707  *	Set destination address.
2708  *	Special case for SIT interfaces where we create a new "virtual"
2709  *	device.
2710  */
2711 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2712 {
2713 	struct in6_ifreq ireq;
2714 	struct net_device *dev;
2715 	int err = -EINVAL;
2716 
2717 	rtnl_lock();
2718 
2719 	err = -EFAULT;
2720 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2721 		goto err_exit;
2722 
2723 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2724 
2725 	err = -ENODEV;
2726 	if (!dev)
2727 		goto err_exit;
2728 
2729 #if IS_ENABLED(CONFIG_IPV6_SIT)
2730 	if (dev->type == ARPHRD_SIT) {
2731 		const struct net_device_ops *ops = dev->netdev_ops;
2732 		struct ifreq ifr;
2733 		struct ip_tunnel_parm p;
2734 
2735 		err = -EADDRNOTAVAIL;
2736 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2737 			goto err_exit;
2738 
2739 		memset(&p, 0, sizeof(p));
2740 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2741 		p.iph.saddr = 0;
2742 		p.iph.version = 4;
2743 		p.iph.ihl = 5;
2744 		p.iph.protocol = IPPROTO_IPV6;
2745 		p.iph.ttl = 64;
2746 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2747 
2748 		if (ops->ndo_do_ioctl) {
2749 			mm_segment_t oldfs = get_fs();
2750 
2751 			set_fs(KERNEL_DS);
2752 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2753 			set_fs(oldfs);
2754 		} else
2755 			err = -EOPNOTSUPP;
2756 
2757 		if (err == 0) {
2758 			err = -ENOBUFS;
2759 			dev = __dev_get_by_name(net, p.name);
2760 			if (!dev)
2761 				goto err_exit;
2762 			err = dev_open(dev);
2763 		}
2764 	}
2765 #endif
2766 
2767 err_exit:
2768 	rtnl_unlock();
2769 	return err;
2770 }
2771 
2772 static int ipv6_mc_config(struct sock *sk, bool join,
2773 			  const struct in6_addr *addr, int ifindex)
2774 {
2775 	int ret;
2776 
2777 	ASSERT_RTNL();
2778 
2779 	lock_sock(sk);
2780 	if (join)
2781 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2782 	else
2783 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2784 	release_sock(sk);
2785 
2786 	return ret;
2787 }
2788 
2789 /*
2790  *	Manual configuration of address on an interface
2791  */
2792 static int inet6_addr_add(struct net *net, int ifindex,
2793 			  const struct in6_addr *pfx,
2794 			  const struct in6_addr *peer_pfx,
2795 			  unsigned int plen, __u32 ifa_flags,
2796 			  __u32 prefered_lft, __u32 valid_lft)
2797 {
2798 	struct inet6_ifaddr *ifp;
2799 	struct inet6_dev *idev;
2800 	struct net_device *dev;
2801 	unsigned long timeout;
2802 	clock_t expires;
2803 	int scope;
2804 	u32 flags;
2805 
2806 	ASSERT_RTNL();
2807 
2808 	if (plen > 128)
2809 		return -EINVAL;
2810 
2811 	/* check the lifetime */
2812 	if (!valid_lft || prefered_lft > valid_lft)
2813 		return -EINVAL;
2814 
2815 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2816 		return -EINVAL;
2817 
2818 	dev = __dev_get_by_index(net, ifindex);
2819 	if (!dev)
2820 		return -ENODEV;
2821 
2822 	idev = addrconf_add_dev(dev);
2823 	if (IS_ERR(idev))
2824 		return PTR_ERR(idev);
2825 
2826 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2827 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2828 					 true, pfx, ifindex);
2829 
2830 		if (ret < 0)
2831 			return ret;
2832 	}
2833 
2834 	scope = ipv6_addr_scope(pfx);
2835 
2836 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2837 	if (addrconf_finite_timeout(timeout)) {
2838 		expires = jiffies_to_clock_t(timeout * HZ);
2839 		valid_lft = timeout;
2840 		flags = RTF_EXPIRES;
2841 	} else {
2842 		expires = 0;
2843 		flags = 0;
2844 		ifa_flags |= IFA_F_PERMANENT;
2845 	}
2846 
2847 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2848 	if (addrconf_finite_timeout(timeout)) {
2849 		if (timeout == 0)
2850 			ifa_flags |= IFA_F_DEPRECATED;
2851 		prefered_lft = timeout;
2852 	}
2853 
2854 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2855 			    valid_lft, prefered_lft);
2856 
2857 	if (!IS_ERR(ifp)) {
2858 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2859 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2860 					      expires, flags);
2861 		}
2862 
2863 		/*
2864 		 * Note that section 3.1 of RFC 4429 indicates
2865 		 * that the Optimistic flag should not be set for
2866 		 * manually configured addresses
2867 		 */
2868 		addrconf_dad_start(ifp);
2869 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2870 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2871 					 true, jiffies);
2872 		in6_ifa_put(ifp);
2873 		addrconf_verify_rtnl();
2874 		return 0;
2875 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2876 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2877 			       false, pfx, ifindex);
2878 	}
2879 
2880 	return PTR_ERR(ifp);
2881 }
2882 
2883 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2884 			  const struct in6_addr *pfx, unsigned int plen)
2885 {
2886 	struct inet6_ifaddr *ifp;
2887 	struct inet6_dev *idev;
2888 	struct net_device *dev;
2889 
2890 	if (plen > 128)
2891 		return -EINVAL;
2892 
2893 	dev = __dev_get_by_index(net, ifindex);
2894 	if (!dev)
2895 		return -ENODEV;
2896 
2897 	idev = __in6_dev_get(dev);
2898 	if (!idev)
2899 		return -ENXIO;
2900 
2901 	read_lock_bh(&idev->lock);
2902 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2903 		if (ifp->prefix_len == plen &&
2904 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2905 			in6_ifa_hold(ifp);
2906 			read_unlock_bh(&idev->lock);
2907 
2908 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2909 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2910 				manage_tempaddrs(idev, ifp, 0, 0, false,
2911 						 jiffies);
2912 			ipv6_del_addr(ifp);
2913 			addrconf_verify_rtnl();
2914 			if (ipv6_addr_is_multicast(pfx)) {
2915 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2916 					       false, pfx, dev->ifindex);
2917 			}
2918 			return 0;
2919 		}
2920 	}
2921 	read_unlock_bh(&idev->lock);
2922 	return -EADDRNOTAVAIL;
2923 }
2924 
2925 
2926 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2927 {
2928 	struct in6_ifreq ireq;
2929 	int err;
2930 
2931 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2932 		return -EPERM;
2933 
2934 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2935 		return -EFAULT;
2936 
2937 	rtnl_lock();
2938 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2939 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2940 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2941 	rtnl_unlock();
2942 	return err;
2943 }
2944 
2945 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2946 {
2947 	struct in6_ifreq ireq;
2948 	int err;
2949 
2950 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2951 		return -EPERM;
2952 
2953 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2954 		return -EFAULT;
2955 
2956 	rtnl_lock();
2957 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2958 			     ireq.ifr6_prefixlen);
2959 	rtnl_unlock();
2960 	return err;
2961 }
2962 
2963 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2964 		     int plen, int scope)
2965 {
2966 	struct inet6_ifaddr *ifp;
2967 
2968 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2969 			    scope, IFA_F_PERMANENT,
2970 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2971 	if (!IS_ERR(ifp)) {
2972 		spin_lock_bh(&ifp->lock);
2973 		ifp->flags &= ~IFA_F_TENTATIVE;
2974 		spin_unlock_bh(&ifp->lock);
2975 		rt_genid_bump_ipv6(dev_net(idev->dev));
2976 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2977 		in6_ifa_put(ifp);
2978 	}
2979 }
2980 
2981 #if IS_ENABLED(CONFIG_IPV6_SIT)
2982 static void sit_add_v4_addrs(struct inet6_dev *idev)
2983 {
2984 	struct in6_addr addr;
2985 	struct net_device *dev;
2986 	struct net *net = dev_net(idev->dev);
2987 	int scope, plen;
2988 	u32 pflags = 0;
2989 
2990 	ASSERT_RTNL();
2991 
2992 	memset(&addr, 0, sizeof(struct in6_addr));
2993 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2994 
2995 	if (idev->dev->flags&IFF_POINTOPOINT) {
2996 		addr.s6_addr32[0] = htonl(0xfe800000);
2997 		scope = IFA_LINK;
2998 		plen = 64;
2999 	} else {
3000 		scope = IPV6_ADDR_COMPATv4;
3001 		plen = 96;
3002 		pflags |= RTF_NONEXTHOP;
3003 	}
3004 
3005 	if (addr.s6_addr32[3]) {
3006 		add_addr(idev, &addr, plen, scope);
3007 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
3008 		return;
3009 	}
3010 
3011 	for_each_netdev(net, dev) {
3012 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3013 		if (in_dev && (dev->flags & IFF_UP)) {
3014 			struct in_ifaddr *ifa;
3015 
3016 			int flag = scope;
3017 
3018 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3019 
3020 				addr.s6_addr32[3] = ifa->ifa_local;
3021 
3022 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3023 					continue;
3024 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3025 					if (idev->dev->flags&IFF_POINTOPOINT)
3026 						continue;
3027 					flag |= IFA_HOST;
3028 				}
3029 
3030 				add_addr(idev, &addr, plen, flag);
3031 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3032 						      pflags);
3033 			}
3034 		}
3035 	}
3036 }
3037 #endif
3038 
3039 static void init_loopback(struct net_device *dev)
3040 {
3041 	struct inet6_dev  *idev;
3042 
3043 	/* ::1 */
3044 
3045 	ASSERT_RTNL();
3046 
3047 	idev = ipv6_find_idev(dev);
3048 	if (!idev) {
3049 		pr_debug("%s: add_dev failed\n", __func__);
3050 		return;
3051 	}
3052 
3053 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3054 }
3055 
3056 void addrconf_add_linklocal(struct inet6_dev *idev,
3057 			    const struct in6_addr *addr, u32 flags)
3058 {
3059 	struct inet6_ifaddr *ifp;
3060 	u32 addr_flags = flags | IFA_F_PERMANENT;
3061 
3062 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3063 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3064 	     idev->cnf.optimistic_dad) &&
3065 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3066 		addr_flags |= IFA_F_OPTIMISTIC;
3067 #endif
3068 
3069 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3070 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
3071 	if (!IS_ERR(ifp)) {
3072 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3073 		addrconf_dad_start(ifp);
3074 		in6_ifa_put(ifp);
3075 	}
3076 }
3077 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3078 
3079 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3080 {
3081 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3082 		return true;
3083 
3084 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3085 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3086 		return true;
3087 
3088 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3089 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3090 		return true;
3091 
3092 	return false;
3093 }
3094 
3095 static int ipv6_generate_stable_address(struct in6_addr *address,
3096 					u8 dad_count,
3097 					const struct inet6_dev *idev)
3098 {
3099 	static DEFINE_SPINLOCK(lock);
3100 	static __u32 digest[SHA_DIGEST_WORDS];
3101 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3102 
3103 	static union {
3104 		char __data[SHA_MESSAGE_BYTES];
3105 		struct {
3106 			struct in6_addr secret;
3107 			__be32 prefix[2];
3108 			unsigned char hwaddr[MAX_ADDR_LEN];
3109 			u8 dad_count;
3110 		} __packed;
3111 	} data;
3112 
3113 	struct in6_addr secret;
3114 	struct in6_addr temp;
3115 	struct net *net = dev_net(idev->dev);
3116 
3117 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3118 
3119 	if (idev->cnf.stable_secret.initialized)
3120 		secret = idev->cnf.stable_secret.secret;
3121 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3122 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3123 	else
3124 		return -1;
3125 
3126 retry:
3127 	spin_lock_bh(&lock);
3128 
3129 	sha_init(digest);
3130 	memset(&data, 0, sizeof(data));
3131 	memset(workspace, 0, sizeof(workspace));
3132 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3133 	data.prefix[0] = address->s6_addr32[0];
3134 	data.prefix[1] = address->s6_addr32[1];
3135 	data.secret = secret;
3136 	data.dad_count = dad_count;
3137 
3138 	sha_transform(digest, data.__data, workspace);
3139 
3140 	temp = *address;
3141 	temp.s6_addr32[2] = (__force __be32)digest[0];
3142 	temp.s6_addr32[3] = (__force __be32)digest[1];
3143 
3144 	spin_unlock_bh(&lock);
3145 
3146 	if (ipv6_reserved_interfaceid(temp)) {
3147 		dad_count++;
3148 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3149 			return -1;
3150 		goto retry;
3151 	}
3152 
3153 	*address = temp;
3154 	return 0;
3155 }
3156 
3157 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3158 {
3159 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3160 
3161 	if (s->initialized)
3162 		return;
3163 	s = &idev->cnf.stable_secret;
3164 	get_random_bytes(&s->secret, sizeof(s->secret));
3165 	s->initialized = true;
3166 }
3167 
3168 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3169 {
3170 	struct in6_addr addr;
3171 
3172 	/* no link local addresses on L3 master devices */
3173 	if (netif_is_l3_master(idev->dev))
3174 		return;
3175 
3176 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3177 
3178 	switch (idev->cnf.addr_gen_mode) {
3179 	case IN6_ADDR_GEN_MODE_RANDOM:
3180 		ipv6_gen_mode_random_init(idev);
3181 		/* fallthrough */
3182 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3183 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3184 			addrconf_add_linklocal(idev, &addr,
3185 					       IFA_F_STABLE_PRIVACY);
3186 		else if (prefix_route)
3187 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3188 		break;
3189 	case IN6_ADDR_GEN_MODE_EUI64:
3190 		/* addrconf_add_linklocal also adds a prefix_route and we
3191 		 * only need to care about prefix routes if ipv6_generate_eui64
3192 		 * couldn't generate one.
3193 		 */
3194 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3195 			addrconf_add_linklocal(idev, &addr, 0);
3196 		else if (prefix_route)
3197 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3198 		break;
3199 	case IN6_ADDR_GEN_MODE_NONE:
3200 	default:
3201 		/* will not add any link local address */
3202 		break;
3203 	}
3204 }
3205 
3206 static void addrconf_dev_config(struct net_device *dev)
3207 {
3208 	struct inet6_dev *idev;
3209 
3210 	ASSERT_RTNL();
3211 
3212 	if ((dev->type != ARPHRD_ETHER) &&
3213 	    (dev->type != ARPHRD_FDDI) &&
3214 	    (dev->type != ARPHRD_ARCNET) &&
3215 	    (dev->type != ARPHRD_INFINIBAND) &&
3216 	    (dev->type != ARPHRD_IEEE1394) &&
3217 	    (dev->type != ARPHRD_TUNNEL6) &&
3218 	    (dev->type != ARPHRD_6LOWPAN) &&
3219 	    (dev->type != ARPHRD_IP6GRE) &&
3220 	    (dev->type != ARPHRD_IPGRE) &&
3221 	    (dev->type != ARPHRD_TUNNEL) &&
3222 	    (dev->type != ARPHRD_NONE)) {
3223 		/* Alas, we support only Ethernet autoconfiguration. */
3224 		return;
3225 	}
3226 
3227 	idev = addrconf_add_dev(dev);
3228 	if (IS_ERR(idev))
3229 		return;
3230 
3231 	/* this device type has no EUI support */
3232 	if (dev->type == ARPHRD_NONE &&
3233 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3234 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3235 
3236 	addrconf_addr_gen(idev, false);
3237 }
3238 
3239 #if IS_ENABLED(CONFIG_IPV6_SIT)
3240 static void addrconf_sit_config(struct net_device *dev)
3241 {
3242 	struct inet6_dev *idev;
3243 
3244 	ASSERT_RTNL();
3245 
3246 	/*
3247 	 * Configure the tunnel with one of our IPv4
3248 	 * addresses... we should configure all of
3249 	 * our v4 addrs in the tunnel
3250 	 */
3251 
3252 	idev = ipv6_find_idev(dev);
3253 	if (!idev) {
3254 		pr_debug("%s: add_dev failed\n", __func__);
3255 		return;
3256 	}
3257 
3258 	if (dev->priv_flags & IFF_ISATAP) {
3259 		addrconf_addr_gen(idev, false);
3260 		return;
3261 	}
3262 
3263 	sit_add_v4_addrs(idev);
3264 
3265 	if (dev->flags&IFF_POINTOPOINT)
3266 		addrconf_add_mroute(dev);
3267 }
3268 #endif
3269 
3270 #if IS_ENABLED(CONFIG_NET_IPGRE)
3271 static void addrconf_gre_config(struct net_device *dev)
3272 {
3273 	struct inet6_dev *idev;
3274 
3275 	ASSERT_RTNL();
3276 
3277 	idev = ipv6_find_idev(dev);
3278 	if (!idev) {
3279 		pr_debug("%s: add_dev failed\n", __func__);
3280 		return;
3281 	}
3282 
3283 	addrconf_addr_gen(idev, true);
3284 	if (dev->flags & IFF_POINTOPOINT)
3285 		addrconf_add_mroute(dev);
3286 }
3287 #endif
3288 
3289 static int fixup_permanent_addr(struct inet6_dev *idev,
3290 				struct inet6_ifaddr *ifp)
3291 {
3292 	/* !rt6i_node means the host route was removed from the
3293 	 * FIB, for example, if 'lo' device is taken down. In that
3294 	 * case regenerate the host route.
3295 	 */
3296 	if (!ifp->rt || !ifp->rt->rt6i_node) {
3297 		struct rt6_info *rt, *prev;
3298 
3299 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3300 		if (unlikely(IS_ERR(rt)))
3301 			return PTR_ERR(rt);
3302 
3303 		/* ifp->rt can be accessed outside of rtnl */
3304 		spin_lock(&ifp->lock);
3305 		prev = ifp->rt;
3306 		ifp->rt = rt;
3307 		spin_unlock(&ifp->lock);
3308 
3309 		ip6_rt_put(prev);
3310 	}
3311 
3312 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3313 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3314 				      idev->dev, 0, 0);
3315 	}
3316 
3317 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3318 		addrconf_dad_start(ifp);
3319 
3320 	return 0;
3321 }
3322 
3323 static void addrconf_permanent_addr(struct net_device *dev)
3324 {
3325 	struct inet6_ifaddr *ifp, *tmp;
3326 	struct inet6_dev *idev;
3327 
3328 	idev = __in6_dev_get(dev);
3329 	if (!idev)
3330 		return;
3331 
3332 	write_lock_bh(&idev->lock);
3333 
3334 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3335 		if ((ifp->flags & IFA_F_PERMANENT) &&
3336 		    fixup_permanent_addr(idev, ifp) < 0) {
3337 			write_unlock_bh(&idev->lock);
3338 			ipv6_del_addr(ifp);
3339 			write_lock_bh(&idev->lock);
3340 
3341 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3342 					     idev->dev->name, &ifp->addr);
3343 		}
3344 	}
3345 
3346 	write_unlock_bh(&idev->lock);
3347 }
3348 
3349 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3350 			   void *ptr)
3351 {
3352 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3353 	struct netdev_notifier_changeupper_info *info;
3354 	struct inet6_dev *idev = __in6_dev_get(dev);
3355 	struct net *net = dev_net(dev);
3356 	int run_pending = 0;
3357 	int err;
3358 
3359 	switch (event) {
3360 	case NETDEV_REGISTER:
3361 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3362 			idev = ipv6_add_dev(dev);
3363 			if (IS_ERR(idev))
3364 				return notifier_from_errno(PTR_ERR(idev));
3365 		}
3366 		break;
3367 
3368 	case NETDEV_CHANGEMTU:
3369 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3370 		if (dev->mtu < IPV6_MIN_MTU) {
3371 			addrconf_ifdown(dev, dev != net->loopback_dev);
3372 			break;
3373 		}
3374 
3375 		if (idev) {
3376 			rt6_mtu_change(dev, dev->mtu);
3377 			idev->cnf.mtu6 = dev->mtu;
3378 			break;
3379 		}
3380 
3381 		/* allocate new idev */
3382 		idev = ipv6_add_dev(dev);
3383 		if (IS_ERR(idev))
3384 			break;
3385 
3386 		/* device is still not ready */
3387 		if (!(idev->if_flags & IF_READY))
3388 			break;
3389 
3390 		run_pending = 1;
3391 
3392 		/* fall through */
3393 
3394 	case NETDEV_UP:
3395 	case NETDEV_CHANGE:
3396 		if (dev->flags & IFF_SLAVE)
3397 			break;
3398 
3399 		if (idev && idev->cnf.disable_ipv6)
3400 			break;
3401 
3402 		if (event == NETDEV_UP) {
3403 			/* restore routes for permanent addresses */
3404 			addrconf_permanent_addr(dev);
3405 
3406 			if (!addrconf_qdisc_ok(dev)) {
3407 				/* device is not ready yet. */
3408 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3409 					dev->name);
3410 				break;
3411 			}
3412 
3413 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3414 				idev = ipv6_add_dev(dev);
3415 
3416 			if (!IS_ERR_OR_NULL(idev)) {
3417 				idev->if_flags |= IF_READY;
3418 				run_pending = 1;
3419 			}
3420 		} else if (event == NETDEV_CHANGE) {
3421 			if (!addrconf_qdisc_ok(dev)) {
3422 				/* device is still not ready. */
3423 				break;
3424 			}
3425 
3426 			if (idev) {
3427 				if (idev->if_flags & IF_READY) {
3428 					/* device is already configured -
3429 					 * but resend MLD reports, we might
3430 					 * have roamed and need to update
3431 					 * multicast snooping switches
3432 					 */
3433 					ipv6_mc_up(idev);
3434 					break;
3435 				}
3436 				idev->if_flags |= IF_READY;
3437 			}
3438 
3439 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3440 				dev->name);
3441 
3442 			run_pending = 1;
3443 		}
3444 
3445 		switch (dev->type) {
3446 #if IS_ENABLED(CONFIG_IPV6_SIT)
3447 		case ARPHRD_SIT:
3448 			addrconf_sit_config(dev);
3449 			break;
3450 #endif
3451 #if IS_ENABLED(CONFIG_NET_IPGRE)
3452 		case ARPHRD_IPGRE:
3453 			addrconf_gre_config(dev);
3454 			break;
3455 #endif
3456 		case ARPHRD_LOOPBACK:
3457 			init_loopback(dev);
3458 			break;
3459 
3460 		default:
3461 			addrconf_dev_config(dev);
3462 			break;
3463 		}
3464 
3465 		if (!IS_ERR_OR_NULL(idev)) {
3466 			if (run_pending)
3467 				addrconf_dad_run(idev);
3468 
3469 			/*
3470 			 * If the MTU changed during the interface down,
3471 			 * when the interface up, the changed MTU must be
3472 			 * reflected in the idev as well as routers.
3473 			 */
3474 			if (idev->cnf.mtu6 != dev->mtu &&
3475 			    dev->mtu >= IPV6_MIN_MTU) {
3476 				rt6_mtu_change(dev, dev->mtu);
3477 				idev->cnf.mtu6 = dev->mtu;
3478 			}
3479 			idev->tstamp = jiffies;
3480 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3481 
3482 			/*
3483 			 * If the changed mtu during down is lower than
3484 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3485 			 */
3486 			if (dev->mtu < IPV6_MIN_MTU)
3487 				addrconf_ifdown(dev, dev != net->loopback_dev);
3488 		}
3489 		break;
3490 
3491 	case NETDEV_DOWN:
3492 	case NETDEV_UNREGISTER:
3493 		/*
3494 		 *	Remove all addresses from this interface.
3495 		 */
3496 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3497 		break;
3498 
3499 	case NETDEV_CHANGENAME:
3500 		if (idev) {
3501 			snmp6_unregister_dev(idev);
3502 			addrconf_sysctl_unregister(idev);
3503 			err = addrconf_sysctl_register(idev);
3504 			if (err)
3505 				return notifier_from_errno(err);
3506 			err = snmp6_register_dev(idev);
3507 			if (err) {
3508 				addrconf_sysctl_unregister(idev);
3509 				return notifier_from_errno(err);
3510 			}
3511 		}
3512 		break;
3513 
3514 	case NETDEV_PRE_TYPE_CHANGE:
3515 	case NETDEV_POST_TYPE_CHANGE:
3516 		if (idev)
3517 			addrconf_type_change(dev, event);
3518 		break;
3519 
3520 	case NETDEV_CHANGEUPPER:
3521 		info = ptr;
3522 
3523 		/* flush all routes if dev is linked to or unlinked from
3524 		 * an L3 master device (e.g., VRF)
3525 		 */
3526 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3527 			addrconf_ifdown(dev, 0);
3528 	}
3529 
3530 	return NOTIFY_OK;
3531 }
3532 
3533 /*
3534  *	addrconf module should be notified of a device going up
3535  */
3536 static struct notifier_block ipv6_dev_notf = {
3537 	.notifier_call = addrconf_notify,
3538 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3539 };
3540 
3541 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3542 {
3543 	struct inet6_dev *idev;
3544 	ASSERT_RTNL();
3545 
3546 	idev = __in6_dev_get(dev);
3547 
3548 	if (event == NETDEV_POST_TYPE_CHANGE)
3549 		ipv6_mc_remap(idev);
3550 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3551 		ipv6_mc_unmap(idev);
3552 }
3553 
3554 static bool addr_is_local(const struct in6_addr *addr)
3555 {
3556 	return ipv6_addr_type(addr) &
3557 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3558 }
3559 
3560 static int addrconf_ifdown(struct net_device *dev, int how)
3561 {
3562 	struct net *net = dev_net(dev);
3563 	struct inet6_dev *idev;
3564 	struct inet6_ifaddr *ifa, *tmp;
3565 	struct list_head del_list;
3566 	int _keep_addr;
3567 	bool keep_addr;
3568 	int state, i;
3569 
3570 	ASSERT_RTNL();
3571 
3572 	rt6_ifdown(net, dev);
3573 	neigh_ifdown(&nd_tbl, dev);
3574 
3575 	idev = __in6_dev_get(dev);
3576 	if (!idev)
3577 		return -ENODEV;
3578 
3579 	/*
3580 	 * Step 1: remove reference to ipv6 device from parent device.
3581 	 *	   Do not dev_put!
3582 	 */
3583 	if (how) {
3584 		idev->dead = 1;
3585 
3586 		/* protected by rtnl_lock */
3587 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3588 
3589 		/* Step 1.5: remove snmp6 entry */
3590 		snmp6_unregister_dev(idev);
3591 
3592 	}
3593 
3594 	/* aggregate the system setting and interface setting */
3595 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3596 	if (!_keep_addr)
3597 		_keep_addr = idev->cnf.keep_addr_on_down;
3598 
3599 	/* combine the user config with event to determine if permanent
3600 	 * addresses are to be removed from address hash table
3601 	 */
3602 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3603 
3604 	/* Step 2: clear hash table */
3605 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3606 		struct hlist_head *h = &inet6_addr_lst[i];
3607 
3608 		spin_lock_bh(&addrconf_hash_lock);
3609 restart:
3610 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3611 			if (ifa->idev == idev) {
3612 				addrconf_del_dad_work(ifa);
3613 				/* combined flag + permanent flag decide if
3614 				 * address is retained on a down event
3615 				 */
3616 				if (!keep_addr ||
3617 				    !(ifa->flags & IFA_F_PERMANENT) ||
3618 				    addr_is_local(&ifa->addr)) {
3619 					hlist_del_init_rcu(&ifa->addr_lst);
3620 					goto restart;
3621 				}
3622 			}
3623 		}
3624 		spin_unlock_bh(&addrconf_hash_lock);
3625 	}
3626 
3627 	write_lock_bh(&idev->lock);
3628 
3629 	addrconf_del_rs_timer(idev);
3630 
3631 	/* Step 2: clear flags for stateless addrconf */
3632 	if (!how)
3633 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3634 
3635 	/* Step 3: clear tempaddr list */
3636 	while (!list_empty(&idev->tempaddr_list)) {
3637 		ifa = list_first_entry(&idev->tempaddr_list,
3638 				       struct inet6_ifaddr, tmp_list);
3639 		list_del(&ifa->tmp_list);
3640 		write_unlock_bh(&idev->lock);
3641 		spin_lock_bh(&ifa->lock);
3642 
3643 		if (ifa->ifpub) {
3644 			in6_ifa_put(ifa->ifpub);
3645 			ifa->ifpub = NULL;
3646 		}
3647 		spin_unlock_bh(&ifa->lock);
3648 		in6_ifa_put(ifa);
3649 		write_lock_bh(&idev->lock);
3650 	}
3651 
3652 	/* re-combine the user config with event to determine if permanent
3653 	 * addresses are to be removed from the interface list
3654 	 */
3655 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3656 
3657 	INIT_LIST_HEAD(&del_list);
3658 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3659 		struct rt6_info *rt = NULL;
3660 		bool keep;
3661 
3662 		addrconf_del_dad_work(ifa);
3663 
3664 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3665 			!addr_is_local(&ifa->addr);
3666 		if (!keep)
3667 			list_move(&ifa->if_list, &del_list);
3668 
3669 		write_unlock_bh(&idev->lock);
3670 		spin_lock_bh(&ifa->lock);
3671 
3672 		if (keep) {
3673 			/* set state to skip the notifier below */
3674 			state = INET6_IFADDR_STATE_DEAD;
3675 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3676 			if (!(ifa->flags & IFA_F_NODAD))
3677 				ifa->flags |= IFA_F_TENTATIVE;
3678 
3679 			rt = ifa->rt;
3680 			ifa->rt = NULL;
3681 		} else {
3682 			state = ifa->state;
3683 			ifa->state = INET6_IFADDR_STATE_DEAD;
3684 		}
3685 
3686 		spin_unlock_bh(&ifa->lock);
3687 
3688 		if (rt)
3689 			ip6_del_rt(rt);
3690 
3691 		if (state != INET6_IFADDR_STATE_DEAD) {
3692 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3693 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3694 		} else {
3695 			if (idev->cnf.forwarding)
3696 				addrconf_leave_anycast(ifa);
3697 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3698 		}
3699 
3700 		write_lock_bh(&idev->lock);
3701 	}
3702 
3703 	write_unlock_bh(&idev->lock);
3704 
3705 	/* now clean up addresses to be removed */
3706 	while (!list_empty(&del_list)) {
3707 		ifa = list_first_entry(&del_list,
3708 				       struct inet6_ifaddr, if_list);
3709 		list_del(&ifa->if_list);
3710 
3711 		in6_ifa_put(ifa);
3712 	}
3713 
3714 	/* Step 5: Discard anycast and multicast list */
3715 	if (how) {
3716 		ipv6_ac_destroy_dev(idev);
3717 		ipv6_mc_destroy_dev(idev);
3718 	} else {
3719 		ipv6_mc_down(idev);
3720 	}
3721 
3722 	idev->tstamp = jiffies;
3723 
3724 	/* Last: Shot the device (if unregistered) */
3725 	if (how) {
3726 		addrconf_sysctl_unregister(idev);
3727 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3728 		neigh_ifdown(&nd_tbl, dev);
3729 		in6_dev_put(idev);
3730 	}
3731 	return 0;
3732 }
3733 
3734 static void addrconf_rs_timer(unsigned long data)
3735 {
3736 	struct inet6_dev *idev = (struct inet6_dev *)data;
3737 	struct net_device *dev = idev->dev;
3738 	struct in6_addr lladdr;
3739 
3740 	write_lock(&idev->lock);
3741 	if (idev->dead || !(idev->if_flags & IF_READY))
3742 		goto out;
3743 
3744 	if (!ipv6_accept_ra(idev))
3745 		goto out;
3746 
3747 	/* Announcement received after solicitation was sent */
3748 	if (idev->if_flags & IF_RA_RCVD)
3749 		goto out;
3750 
3751 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3752 		write_unlock(&idev->lock);
3753 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3754 			ndisc_send_rs(dev, &lladdr,
3755 				      &in6addr_linklocal_allrouters);
3756 		else
3757 			goto put;
3758 
3759 		write_lock(&idev->lock);
3760 		idev->rs_interval = rfc3315_s14_backoff_update(
3761 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3762 		/* The wait after the last probe can be shorter */
3763 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3764 					     idev->cnf.rtr_solicits) ?
3765 				      idev->cnf.rtr_solicit_delay :
3766 				      idev->rs_interval);
3767 	} else {
3768 		/*
3769 		 * Note: we do not support deprecated "all on-link"
3770 		 * assumption any longer.
3771 		 */
3772 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3773 	}
3774 
3775 out:
3776 	write_unlock(&idev->lock);
3777 put:
3778 	in6_dev_put(idev);
3779 }
3780 
3781 /*
3782  *	Duplicate Address Detection
3783  */
3784 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3785 {
3786 	unsigned long rand_num;
3787 	struct inet6_dev *idev = ifp->idev;
3788 	u64 nonce;
3789 
3790 	if (ifp->flags & IFA_F_OPTIMISTIC)
3791 		rand_num = 0;
3792 	else
3793 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3794 
3795 	nonce = 0;
3796 	if (idev->cnf.enhanced_dad ||
3797 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3798 		do
3799 			get_random_bytes(&nonce, 6);
3800 		while (nonce == 0);
3801 	}
3802 	ifp->dad_nonce = nonce;
3803 	ifp->dad_probes = idev->cnf.dad_transmits;
3804 	addrconf_mod_dad_work(ifp, rand_num);
3805 }
3806 
3807 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3808 {
3809 	struct inet6_dev *idev = ifp->idev;
3810 	struct net_device *dev = idev->dev;
3811 	bool bump_id, notify = false;
3812 
3813 	addrconf_join_solict(dev, &ifp->addr);
3814 
3815 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3816 
3817 	read_lock_bh(&idev->lock);
3818 	spin_lock(&ifp->lock);
3819 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3820 		goto out;
3821 
3822 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3823 	    (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 &&
3824 	     idev->cnf.accept_dad < 1) ||
3825 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3826 	    ifp->flags & IFA_F_NODAD) {
3827 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3828 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3829 		spin_unlock(&ifp->lock);
3830 		read_unlock_bh(&idev->lock);
3831 
3832 		addrconf_dad_completed(ifp, bump_id);
3833 		return;
3834 	}
3835 
3836 	if (!(idev->if_flags & IF_READY)) {
3837 		spin_unlock(&ifp->lock);
3838 		read_unlock_bh(&idev->lock);
3839 		/*
3840 		 * If the device is not ready:
3841 		 * - keep it tentative if it is a permanent address.
3842 		 * - otherwise, kill it.
3843 		 */
3844 		in6_ifa_hold(ifp);
3845 		addrconf_dad_stop(ifp, 0);
3846 		return;
3847 	}
3848 
3849 	/*
3850 	 * Optimistic nodes can start receiving
3851 	 * Frames right away
3852 	 */
3853 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3854 		ip6_ins_rt(ifp->rt);
3855 		if (ipv6_use_optimistic_addr(dev_net(dev), idev)) {
3856 			/* Because optimistic nodes can use this address,
3857 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3858 			 */
3859 			notify = true;
3860 		}
3861 	}
3862 
3863 	addrconf_dad_kick(ifp);
3864 out:
3865 	spin_unlock(&ifp->lock);
3866 	read_unlock_bh(&idev->lock);
3867 	if (notify)
3868 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3869 }
3870 
3871 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3872 {
3873 	bool begin_dad = false;
3874 
3875 	spin_lock_bh(&ifp->lock);
3876 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3877 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3878 		begin_dad = true;
3879 	}
3880 	spin_unlock_bh(&ifp->lock);
3881 
3882 	if (begin_dad)
3883 		addrconf_mod_dad_work(ifp, 0);
3884 }
3885 
3886 static void addrconf_dad_work(struct work_struct *w)
3887 {
3888 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3889 						struct inet6_ifaddr,
3890 						dad_work);
3891 	struct inet6_dev *idev = ifp->idev;
3892 	bool bump_id, disable_ipv6 = false;
3893 	struct in6_addr mcaddr;
3894 
3895 	enum {
3896 		DAD_PROCESS,
3897 		DAD_BEGIN,
3898 		DAD_ABORT,
3899 	} action = DAD_PROCESS;
3900 
3901 	rtnl_lock();
3902 
3903 	spin_lock_bh(&ifp->lock);
3904 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3905 		action = DAD_BEGIN;
3906 		ifp->state = INET6_IFADDR_STATE_DAD;
3907 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3908 		action = DAD_ABORT;
3909 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3910 
3911 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3912 		     idev->cnf.accept_dad > 1) &&
3913 		    !idev->cnf.disable_ipv6 &&
3914 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3915 			struct in6_addr addr;
3916 
3917 			addr.s6_addr32[0] = htonl(0xfe800000);
3918 			addr.s6_addr32[1] = 0;
3919 
3920 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3921 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3922 				/* DAD failed for link-local based on MAC */
3923 				idev->cnf.disable_ipv6 = 1;
3924 
3925 				pr_info("%s: IPv6 being disabled!\n",
3926 					ifp->idev->dev->name);
3927 				disable_ipv6 = true;
3928 			}
3929 		}
3930 	}
3931 	spin_unlock_bh(&ifp->lock);
3932 
3933 	if (action == DAD_BEGIN) {
3934 		addrconf_dad_begin(ifp);
3935 		goto out;
3936 	} else if (action == DAD_ABORT) {
3937 		in6_ifa_hold(ifp);
3938 		addrconf_dad_stop(ifp, 1);
3939 		if (disable_ipv6)
3940 			addrconf_ifdown(idev->dev, 0);
3941 		goto out;
3942 	}
3943 
3944 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3945 		goto out;
3946 
3947 	write_lock_bh(&idev->lock);
3948 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3949 		write_unlock_bh(&idev->lock);
3950 		goto out;
3951 	}
3952 
3953 	spin_lock(&ifp->lock);
3954 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3955 		spin_unlock(&ifp->lock);
3956 		write_unlock_bh(&idev->lock);
3957 		goto out;
3958 	}
3959 
3960 	if (ifp->dad_probes == 0) {
3961 		/*
3962 		 * DAD was successful
3963 		 */
3964 
3965 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3966 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3967 		spin_unlock(&ifp->lock);
3968 		write_unlock_bh(&idev->lock);
3969 
3970 		addrconf_dad_completed(ifp, bump_id);
3971 
3972 		goto out;
3973 	}
3974 
3975 	ifp->dad_probes--;
3976 	addrconf_mod_dad_work(ifp,
3977 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3978 	spin_unlock(&ifp->lock);
3979 	write_unlock_bh(&idev->lock);
3980 
3981 	/* send a neighbour solicitation for our addr */
3982 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3983 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
3984 		      ifp->dad_nonce);
3985 out:
3986 	in6_ifa_put(ifp);
3987 	rtnl_unlock();
3988 }
3989 
3990 /* ifp->idev must be at least read locked */
3991 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3992 {
3993 	struct inet6_ifaddr *ifpiter;
3994 	struct inet6_dev *idev = ifp->idev;
3995 
3996 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
3997 		if (ifpiter->scope > IFA_LINK)
3998 			break;
3999 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4000 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4001 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4002 		    IFA_F_PERMANENT)
4003 			return false;
4004 	}
4005 	return true;
4006 }
4007 
4008 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
4009 {
4010 	struct net_device *dev = ifp->idev->dev;
4011 	struct in6_addr lladdr;
4012 	bool send_rs, send_mld;
4013 
4014 	addrconf_del_dad_work(ifp);
4015 
4016 	/*
4017 	 *	Configure the address for reception. Now it is valid.
4018 	 */
4019 
4020 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4021 
4022 	/* If added prefix is link local and we are prepared to process
4023 	   router advertisements, start sending router solicitations.
4024 	 */
4025 
4026 	read_lock_bh(&ifp->idev->lock);
4027 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4028 	send_rs = send_mld &&
4029 		  ipv6_accept_ra(ifp->idev) &&
4030 		  ifp->idev->cnf.rtr_solicits != 0 &&
4031 		  (dev->flags&IFF_LOOPBACK) == 0;
4032 	read_unlock_bh(&ifp->idev->lock);
4033 
4034 	/* While dad is in progress mld report's source address is in6_addrany.
4035 	 * Resend with proper ll now.
4036 	 */
4037 	if (send_mld)
4038 		ipv6_mc_dad_complete(ifp->idev);
4039 
4040 	if (send_rs) {
4041 		/*
4042 		 *	If a host as already performed a random delay
4043 		 *	[...] as part of DAD [...] there is no need
4044 		 *	to delay again before sending the first RS
4045 		 */
4046 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4047 			return;
4048 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4049 
4050 		write_lock_bh(&ifp->idev->lock);
4051 		spin_lock(&ifp->lock);
4052 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4053 			ifp->idev->cnf.rtr_solicit_interval);
4054 		ifp->idev->rs_probes = 1;
4055 		ifp->idev->if_flags |= IF_RS_SENT;
4056 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4057 		spin_unlock(&ifp->lock);
4058 		write_unlock_bh(&ifp->idev->lock);
4059 	}
4060 
4061 	if (bump_id)
4062 		rt_genid_bump_ipv6(dev_net(dev));
4063 
4064 	/* Make sure that a new temporary address will be created
4065 	 * before this temporary address becomes deprecated.
4066 	 */
4067 	if (ifp->flags & IFA_F_TEMPORARY)
4068 		addrconf_verify_rtnl();
4069 }
4070 
4071 static void addrconf_dad_run(struct inet6_dev *idev)
4072 {
4073 	struct inet6_ifaddr *ifp;
4074 
4075 	read_lock_bh(&idev->lock);
4076 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4077 		spin_lock(&ifp->lock);
4078 		if (ifp->flags & IFA_F_TENTATIVE &&
4079 		    ifp->state == INET6_IFADDR_STATE_DAD)
4080 			addrconf_dad_kick(ifp);
4081 		spin_unlock(&ifp->lock);
4082 	}
4083 	read_unlock_bh(&idev->lock);
4084 }
4085 
4086 #ifdef CONFIG_PROC_FS
4087 struct if6_iter_state {
4088 	struct seq_net_private p;
4089 	int bucket;
4090 	int offset;
4091 };
4092 
4093 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4094 {
4095 	struct inet6_ifaddr *ifa = NULL;
4096 	struct if6_iter_state *state = seq->private;
4097 	struct net *net = seq_file_net(seq);
4098 	int p = 0;
4099 
4100 	/* initial bucket if pos is 0 */
4101 	if (pos == 0) {
4102 		state->bucket = 0;
4103 		state->offset = 0;
4104 	}
4105 
4106 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4107 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4108 					 addr_lst) {
4109 			if (!net_eq(dev_net(ifa->idev->dev), net))
4110 				continue;
4111 			/* sync with offset */
4112 			if (p < state->offset) {
4113 				p++;
4114 				continue;
4115 			}
4116 			state->offset++;
4117 			return ifa;
4118 		}
4119 
4120 		/* prepare for next bucket */
4121 		state->offset = 0;
4122 		p = 0;
4123 	}
4124 	return NULL;
4125 }
4126 
4127 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4128 					 struct inet6_ifaddr *ifa)
4129 {
4130 	struct if6_iter_state *state = seq->private;
4131 	struct net *net = seq_file_net(seq);
4132 
4133 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4134 		if (!net_eq(dev_net(ifa->idev->dev), net))
4135 			continue;
4136 		state->offset++;
4137 		return ifa;
4138 	}
4139 
4140 	while (++state->bucket < IN6_ADDR_HSIZE) {
4141 		state->offset = 0;
4142 		hlist_for_each_entry_rcu_bh(ifa,
4143 				     &inet6_addr_lst[state->bucket], addr_lst) {
4144 			if (!net_eq(dev_net(ifa->idev->dev), net))
4145 				continue;
4146 			state->offset++;
4147 			return ifa;
4148 		}
4149 	}
4150 
4151 	return NULL;
4152 }
4153 
4154 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4155 	__acquires(rcu_bh)
4156 {
4157 	rcu_read_lock_bh();
4158 	return if6_get_first(seq, *pos);
4159 }
4160 
4161 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4162 {
4163 	struct inet6_ifaddr *ifa;
4164 
4165 	ifa = if6_get_next(seq, v);
4166 	++*pos;
4167 	return ifa;
4168 }
4169 
4170 static void if6_seq_stop(struct seq_file *seq, void *v)
4171 	__releases(rcu_bh)
4172 {
4173 	rcu_read_unlock_bh();
4174 }
4175 
4176 static int if6_seq_show(struct seq_file *seq, void *v)
4177 {
4178 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4179 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4180 		   &ifp->addr,
4181 		   ifp->idev->dev->ifindex,
4182 		   ifp->prefix_len,
4183 		   ifp->scope,
4184 		   (u8) ifp->flags,
4185 		   ifp->idev->dev->name);
4186 	return 0;
4187 }
4188 
4189 static const struct seq_operations if6_seq_ops = {
4190 	.start	= if6_seq_start,
4191 	.next	= if6_seq_next,
4192 	.show	= if6_seq_show,
4193 	.stop	= if6_seq_stop,
4194 };
4195 
4196 static int if6_seq_open(struct inode *inode, struct file *file)
4197 {
4198 	return seq_open_net(inode, file, &if6_seq_ops,
4199 			    sizeof(struct if6_iter_state));
4200 }
4201 
4202 static const struct file_operations if6_fops = {
4203 	.owner		= THIS_MODULE,
4204 	.open		= if6_seq_open,
4205 	.read		= seq_read,
4206 	.llseek		= seq_lseek,
4207 	.release	= seq_release_net,
4208 };
4209 
4210 static int __net_init if6_proc_net_init(struct net *net)
4211 {
4212 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4213 		return -ENOMEM;
4214 	return 0;
4215 }
4216 
4217 static void __net_exit if6_proc_net_exit(struct net *net)
4218 {
4219 	remove_proc_entry("if_inet6", net->proc_net);
4220 }
4221 
4222 static struct pernet_operations if6_proc_net_ops = {
4223 	.init = if6_proc_net_init,
4224 	.exit = if6_proc_net_exit,
4225 };
4226 
4227 int __init if6_proc_init(void)
4228 {
4229 	return register_pernet_subsys(&if6_proc_net_ops);
4230 }
4231 
4232 void if6_proc_exit(void)
4233 {
4234 	unregister_pernet_subsys(&if6_proc_net_ops);
4235 }
4236 #endif	/* CONFIG_PROC_FS */
4237 
4238 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4239 /* Check if address is a home address configured on any interface. */
4240 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4241 {
4242 	int ret = 0;
4243 	struct inet6_ifaddr *ifp = NULL;
4244 	unsigned int hash = inet6_addr_hash(addr);
4245 
4246 	rcu_read_lock_bh();
4247 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4248 		if (!net_eq(dev_net(ifp->idev->dev), net))
4249 			continue;
4250 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4251 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4252 			ret = 1;
4253 			break;
4254 		}
4255 	}
4256 	rcu_read_unlock_bh();
4257 	return ret;
4258 }
4259 #endif
4260 
4261 /*
4262  *	Periodic address status verification
4263  */
4264 
4265 static void addrconf_verify_rtnl(void)
4266 {
4267 	unsigned long now, next, next_sec, next_sched;
4268 	struct inet6_ifaddr *ifp;
4269 	int i;
4270 
4271 	ASSERT_RTNL();
4272 
4273 	rcu_read_lock_bh();
4274 	now = jiffies;
4275 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4276 
4277 	cancel_delayed_work(&addr_chk_work);
4278 
4279 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4280 restart:
4281 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4282 			unsigned long age;
4283 
4284 			/* When setting preferred_lft to a value not zero or
4285 			 * infinity, while valid_lft is infinity
4286 			 * IFA_F_PERMANENT has a non-infinity life time.
4287 			 */
4288 			if ((ifp->flags & IFA_F_PERMANENT) &&
4289 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4290 				continue;
4291 
4292 			spin_lock(&ifp->lock);
4293 			/* We try to batch several events at once. */
4294 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4295 
4296 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4297 			    age >= ifp->valid_lft) {
4298 				spin_unlock(&ifp->lock);
4299 				in6_ifa_hold(ifp);
4300 				ipv6_del_addr(ifp);
4301 				goto restart;
4302 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4303 				spin_unlock(&ifp->lock);
4304 				continue;
4305 			} else if (age >= ifp->prefered_lft) {
4306 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4307 				int deprecate = 0;
4308 
4309 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4310 					deprecate = 1;
4311 					ifp->flags |= IFA_F_DEPRECATED;
4312 				}
4313 
4314 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4315 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4316 					next = ifp->tstamp + ifp->valid_lft * HZ;
4317 
4318 				spin_unlock(&ifp->lock);
4319 
4320 				if (deprecate) {
4321 					in6_ifa_hold(ifp);
4322 
4323 					ipv6_ifa_notify(0, ifp);
4324 					in6_ifa_put(ifp);
4325 					goto restart;
4326 				}
4327 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4328 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4329 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4330 					ifp->idev->cnf.dad_transmits *
4331 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4332 
4333 				if (age >= ifp->prefered_lft - regen_advance) {
4334 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4335 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4336 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4337 					if (!ifp->regen_count && ifpub) {
4338 						ifp->regen_count++;
4339 						in6_ifa_hold(ifp);
4340 						in6_ifa_hold(ifpub);
4341 						spin_unlock(&ifp->lock);
4342 
4343 						spin_lock(&ifpub->lock);
4344 						ifpub->regen_count = 0;
4345 						spin_unlock(&ifpub->lock);
4346 						ipv6_create_tempaddr(ifpub, ifp);
4347 						in6_ifa_put(ifpub);
4348 						in6_ifa_put(ifp);
4349 						goto restart;
4350 					}
4351 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4352 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4353 				spin_unlock(&ifp->lock);
4354 			} else {
4355 				/* ifp->prefered_lft <= ifp->valid_lft */
4356 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4357 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4358 				spin_unlock(&ifp->lock);
4359 			}
4360 		}
4361 	}
4362 
4363 	next_sec = round_jiffies_up(next);
4364 	next_sched = next;
4365 
4366 	/* If rounded timeout is accurate enough, accept it. */
4367 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4368 		next_sched = next_sec;
4369 
4370 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4371 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4372 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4373 
4374 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4375 	      now, next, next_sec, next_sched);
4376 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4377 	rcu_read_unlock_bh();
4378 }
4379 
4380 static void addrconf_verify_work(struct work_struct *w)
4381 {
4382 	rtnl_lock();
4383 	addrconf_verify_rtnl();
4384 	rtnl_unlock();
4385 }
4386 
4387 static void addrconf_verify(void)
4388 {
4389 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4390 }
4391 
4392 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4393 				     struct in6_addr **peer_pfx)
4394 {
4395 	struct in6_addr *pfx = NULL;
4396 
4397 	*peer_pfx = NULL;
4398 
4399 	if (addr)
4400 		pfx = nla_data(addr);
4401 
4402 	if (local) {
4403 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4404 			*peer_pfx = pfx;
4405 		pfx = nla_data(local);
4406 	}
4407 
4408 	return pfx;
4409 }
4410 
4411 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4412 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4413 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4414 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4415 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4416 };
4417 
4418 static int
4419 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4420 		  struct netlink_ext_ack *extack)
4421 {
4422 	struct net *net = sock_net(skb->sk);
4423 	struct ifaddrmsg *ifm;
4424 	struct nlattr *tb[IFA_MAX+1];
4425 	struct in6_addr *pfx, *peer_pfx;
4426 	u32 ifa_flags;
4427 	int err;
4428 
4429 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4430 			  extack);
4431 	if (err < 0)
4432 		return err;
4433 
4434 	ifm = nlmsg_data(nlh);
4435 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4436 	if (!pfx)
4437 		return -EINVAL;
4438 
4439 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4440 
4441 	/* We ignore other flags so far. */
4442 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4443 
4444 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4445 			      ifm->ifa_prefixlen);
4446 }
4447 
4448 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4449 			     u32 prefered_lft, u32 valid_lft)
4450 {
4451 	u32 flags;
4452 	clock_t expires;
4453 	unsigned long timeout;
4454 	bool was_managetempaddr;
4455 	bool had_prefixroute;
4456 
4457 	ASSERT_RTNL();
4458 
4459 	if (!valid_lft || (prefered_lft > valid_lft))
4460 		return -EINVAL;
4461 
4462 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4463 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4464 		return -EINVAL;
4465 
4466 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4467 	if (addrconf_finite_timeout(timeout)) {
4468 		expires = jiffies_to_clock_t(timeout * HZ);
4469 		valid_lft = timeout;
4470 		flags = RTF_EXPIRES;
4471 	} else {
4472 		expires = 0;
4473 		flags = 0;
4474 		ifa_flags |= IFA_F_PERMANENT;
4475 	}
4476 
4477 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4478 	if (addrconf_finite_timeout(timeout)) {
4479 		if (timeout == 0)
4480 			ifa_flags |= IFA_F_DEPRECATED;
4481 		prefered_lft = timeout;
4482 	}
4483 
4484 	spin_lock_bh(&ifp->lock);
4485 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4486 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4487 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4488 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4489 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4490 			IFA_F_NOPREFIXROUTE);
4491 	ifp->flags |= ifa_flags;
4492 	ifp->tstamp = jiffies;
4493 	ifp->valid_lft = valid_lft;
4494 	ifp->prefered_lft = prefered_lft;
4495 
4496 	spin_unlock_bh(&ifp->lock);
4497 	if (!(ifp->flags&IFA_F_TENTATIVE))
4498 		ipv6_ifa_notify(0, ifp);
4499 
4500 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4501 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4502 				      expires, flags);
4503 	} else if (had_prefixroute) {
4504 		enum cleanup_prefix_rt_t action;
4505 		unsigned long rt_expires;
4506 
4507 		write_lock_bh(&ifp->idev->lock);
4508 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4509 		write_unlock_bh(&ifp->idev->lock);
4510 
4511 		if (action != CLEANUP_PREFIX_RT_NOP) {
4512 			cleanup_prefix_route(ifp, rt_expires,
4513 				action == CLEANUP_PREFIX_RT_DEL);
4514 		}
4515 	}
4516 
4517 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4518 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4519 			valid_lft = prefered_lft = 0;
4520 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4521 				 !was_managetempaddr, jiffies);
4522 	}
4523 
4524 	addrconf_verify_rtnl();
4525 
4526 	return 0;
4527 }
4528 
4529 static int
4530 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4531 		  struct netlink_ext_ack *extack)
4532 {
4533 	struct net *net = sock_net(skb->sk);
4534 	struct ifaddrmsg *ifm;
4535 	struct nlattr *tb[IFA_MAX+1];
4536 	struct in6_addr *pfx, *peer_pfx;
4537 	struct inet6_ifaddr *ifa;
4538 	struct net_device *dev;
4539 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4540 	u32 ifa_flags;
4541 	int err;
4542 
4543 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4544 			  extack);
4545 	if (err < 0)
4546 		return err;
4547 
4548 	ifm = nlmsg_data(nlh);
4549 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4550 	if (!pfx)
4551 		return -EINVAL;
4552 
4553 	if (tb[IFA_CACHEINFO]) {
4554 		struct ifa_cacheinfo *ci;
4555 
4556 		ci = nla_data(tb[IFA_CACHEINFO]);
4557 		valid_lft = ci->ifa_valid;
4558 		preferred_lft = ci->ifa_prefered;
4559 	} else {
4560 		preferred_lft = INFINITY_LIFE_TIME;
4561 		valid_lft = INFINITY_LIFE_TIME;
4562 	}
4563 
4564 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4565 	if (!dev)
4566 		return -ENODEV;
4567 
4568 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4569 
4570 	/* We ignore other flags so far. */
4571 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4572 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4573 
4574 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4575 	if (!ifa) {
4576 		/*
4577 		 * It would be best to check for !NLM_F_CREATE here but
4578 		 * userspace already relies on not having to provide this.
4579 		 */
4580 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4581 				      ifm->ifa_prefixlen, ifa_flags,
4582 				      preferred_lft, valid_lft);
4583 	}
4584 
4585 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4586 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4587 		err = -EEXIST;
4588 	else
4589 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4590 
4591 	in6_ifa_put(ifa);
4592 
4593 	return err;
4594 }
4595 
4596 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4597 			  u8 scope, int ifindex)
4598 {
4599 	struct ifaddrmsg *ifm;
4600 
4601 	ifm = nlmsg_data(nlh);
4602 	ifm->ifa_family = AF_INET6;
4603 	ifm->ifa_prefixlen = prefixlen;
4604 	ifm->ifa_flags = flags;
4605 	ifm->ifa_scope = scope;
4606 	ifm->ifa_index = ifindex;
4607 }
4608 
4609 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4610 			 unsigned long tstamp, u32 preferred, u32 valid)
4611 {
4612 	struct ifa_cacheinfo ci;
4613 
4614 	ci.cstamp = cstamp_delta(cstamp);
4615 	ci.tstamp = cstamp_delta(tstamp);
4616 	ci.ifa_prefered = preferred;
4617 	ci.ifa_valid = valid;
4618 
4619 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4620 }
4621 
4622 static inline int rt_scope(int ifa_scope)
4623 {
4624 	if (ifa_scope & IFA_HOST)
4625 		return RT_SCOPE_HOST;
4626 	else if (ifa_scope & IFA_LINK)
4627 		return RT_SCOPE_LINK;
4628 	else if (ifa_scope & IFA_SITE)
4629 		return RT_SCOPE_SITE;
4630 	else
4631 		return RT_SCOPE_UNIVERSE;
4632 }
4633 
4634 static inline int inet6_ifaddr_msgsize(void)
4635 {
4636 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4637 	       + nla_total_size(16) /* IFA_LOCAL */
4638 	       + nla_total_size(16) /* IFA_ADDRESS */
4639 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4640 	       + nla_total_size(4)  /* IFA_FLAGS */;
4641 }
4642 
4643 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4644 			     u32 portid, u32 seq, int event, unsigned int flags)
4645 {
4646 	struct nlmsghdr  *nlh;
4647 	u32 preferred, valid;
4648 
4649 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4650 	if (!nlh)
4651 		return -EMSGSIZE;
4652 
4653 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4654 		      ifa->idev->dev->ifindex);
4655 
4656 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4657 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4658 		preferred = ifa->prefered_lft;
4659 		valid = ifa->valid_lft;
4660 		if (preferred != INFINITY_LIFE_TIME) {
4661 			long tval = (jiffies - ifa->tstamp)/HZ;
4662 			if (preferred > tval)
4663 				preferred -= tval;
4664 			else
4665 				preferred = 0;
4666 			if (valid != INFINITY_LIFE_TIME) {
4667 				if (valid > tval)
4668 					valid -= tval;
4669 				else
4670 					valid = 0;
4671 			}
4672 		}
4673 	} else {
4674 		preferred = INFINITY_LIFE_TIME;
4675 		valid = INFINITY_LIFE_TIME;
4676 	}
4677 
4678 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4679 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4680 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4681 			goto error;
4682 	} else
4683 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4684 			goto error;
4685 
4686 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4687 		goto error;
4688 
4689 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4690 		goto error;
4691 
4692 	nlmsg_end(skb, nlh);
4693 	return 0;
4694 
4695 error:
4696 	nlmsg_cancel(skb, nlh);
4697 	return -EMSGSIZE;
4698 }
4699 
4700 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4701 				u32 portid, u32 seq, int event, u16 flags)
4702 {
4703 	struct nlmsghdr  *nlh;
4704 	u8 scope = RT_SCOPE_UNIVERSE;
4705 	int ifindex = ifmca->idev->dev->ifindex;
4706 
4707 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4708 		scope = RT_SCOPE_SITE;
4709 
4710 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4711 	if (!nlh)
4712 		return -EMSGSIZE;
4713 
4714 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4715 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4716 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4717 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4718 		nlmsg_cancel(skb, nlh);
4719 		return -EMSGSIZE;
4720 	}
4721 
4722 	nlmsg_end(skb, nlh);
4723 	return 0;
4724 }
4725 
4726 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4727 				u32 portid, u32 seq, int event, unsigned int flags)
4728 {
4729 	struct nlmsghdr  *nlh;
4730 	u8 scope = RT_SCOPE_UNIVERSE;
4731 	int ifindex = ifaca->aca_idev->dev->ifindex;
4732 
4733 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4734 		scope = RT_SCOPE_SITE;
4735 
4736 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4737 	if (!nlh)
4738 		return -EMSGSIZE;
4739 
4740 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4741 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4742 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4743 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4744 		nlmsg_cancel(skb, nlh);
4745 		return -EMSGSIZE;
4746 	}
4747 
4748 	nlmsg_end(skb, nlh);
4749 	return 0;
4750 }
4751 
4752 enum addr_type_t {
4753 	UNICAST_ADDR,
4754 	MULTICAST_ADDR,
4755 	ANYCAST_ADDR,
4756 };
4757 
4758 /* called with rcu_read_lock() */
4759 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4760 			  struct netlink_callback *cb, enum addr_type_t type,
4761 			  int s_ip_idx, int *p_ip_idx)
4762 {
4763 	struct ifmcaddr6 *ifmca;
4764 	struct ifacaddr6 *ifaca;
4765 	int err = 1;
4766 	int ip_idx = *p_ip_idx;
4767 
4768 	read_lock_bh(&idev->lock);
4769 	switch (type) {
4770 	case UNICAST_ADDR: {
4771 		struct inet6_ifaddr *ifa;
4772 
4773 		/* unicast address incl. temp addr */
4774 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4775 			if (++ip_idx < s_ip_idx)
4776 				continue;
4777 			err = inet6_fill_ifaddr(skb, ifa,
4778 						NETLINK_CB(cb->skb).portid,
4779 						cb->nlh->nlmsg_seq,
4780 						RTM_NEWADDR,
4781 						NLM_F_MULTI);
4782 			if (err < 0)
4783 				break;
4784 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4785 		}
4786 		break;
4787 	}
4788 	case MULTICAST_ADDR:
4789 		/* multicast address */
4790 		for (ifmca = idev->mc_list; ifmca;
4791 		     ifmca = ifmca->next, ip_idx++) {
4792 			if (ip_idx < s_ip_idx)
4793 				continue;
4794 			err = inet6_fill_ifmcaddr(skb, ifmca,
4795 						  NETLINK_CB(cb->skb).portid,
4796 						  cb->nlh->nlmsg_seq,
4797 						  RTM_GETMULTICAST,
4798 						  NLM_F_MULTI);
4799 			if (err < 0)
4800 				break;
4801 		}
4802 		break;
4803 	case ANYCAST_ADDR:
4804 		/* anycast address */
4805 		for (ifaca = idev->ac_list; ifaca;
4806 		     ifaca = ifaca->aca_next, ip_idx++) {
4807 			if (ip_idx < s_ip_idx)
4808 				continue;
4809 			err = inet6_fill_ifacaddr(skb, ifaca,
4810 						  NETLINK_CB(cb->skb).portid,
4811 						  cb->nlh->nlmsg_seq,
4812 						  RTM_GETANYCAST,
4813 						  NLM_F_MULTI);
4814 			if (err < 0)
4815 				break;
4816 		}
4817 		break;
4818 	default:
4819 		break;
4820 	}
4821 	read_unlock_bh(&idev->lock);
4822 	*p_ip_idx = ip_idx;
4823 	return err;
4824 }
4825 
4826 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4827 			   enum addr_type_t type)
4828 {
4829 	struct net *net = sock_net(skb->sk);
4830 	int h, s_h;
4831 	int idx, ip_idx;
4832 	int s_idx, s_ip_idx;
4833 	struct net_device *dev;
4834 	struct inet6_dev *idev;
4835 	struct hlist_head *head;
4836 
4837 	s_h = cb->args[0];
4838 	s_idx = idx = cb->args[1];
4839 	s_ip_idx = ip_idx = cb->args[2];
4840 
4841 	rcu_read_lock();
4842 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4843 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4844 		idx = 0;
4845 		head = &net->dev_index_head[h];
4846 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4847 			if (idx < s_idx)
4848 				goto cont;
4849 			if (h > s_h || idx > s_idx)
4850 				s_ip_idx = 0;
4851 			ip_idx = 0;
4852 			idev = __in6_dev_get(dev);
4853 			if (!idev)
4854 				goto cont;
4855 
4856 			if (in6_dump_addrs(idev, skb, cb, type,
4857 					   s_ip_idx, &ip_idx) < 0)
4858 				goto done;
4859 cont:
4860 			idx++;
4861 		}
4862 	}
4863 done:
4864 	rcu_read_unlock();
4865 	cb->args[0] = h;
4866 	cb->args[1] = idx;
4867 	cb->args[2] = ip_idx;
4868 
4869 	return skb->len;
4870 }
4871 
4872 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4873 {
4874 	enum addr_type_t type = UNICAST_ADDR;
4875 
4876 	return inet6_dump_addr(skb, cb, type);
4877 }
4878 
4879 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4880 {
4881 	enum addr_type_t type = MULTICAST_ADDR;
4882 
4883 	return inet6_dump_addr(skb, cb, type);
4884 }
4885 
4886 
4887 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4888 {
4889 	enum addr_type_t type = ANYCAST_ADDR;
4890 
4891 	return inet6_dump_addr(skb, cb, type);
4892 }
4893 
4894 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4895 			     struct netlink_ext_ack *extack)
4896 {
4897 	struct net *net = sock_net(in_skb->sk);
4898 	struct ifaddrmsg *ifm;
4899 	struct nlattr *tb[IFA_MAX+1];
4900 	struct in6_addr *addr = NULL, *peer;
4901 	struct net_device *dev = NULL;
4902 	struct inet6_ifaddr *ifa;
4903 	struct sk_buff *skb;
4904 	int err;
4905 
4906 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4907 			  extack);
4908 	if (err < 0)
4909 		goto errout;
4910 
4911 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4912 	if (!addr) {
4913 		err = -EINVAL;
4914 		goto errout;
4915 	}
4916 
4917 	ifm = nlmsg_data(nlh);
4918 	if (ifm->ifa_index)
4919 		dev = __dev_get_by_index(net, ifm->ifa_index);
4920 
4921 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4922 	if (!ifa) {
4923 		err = -EADDRNOTAVAIL;
4924 		goto errout;
4925 	}
4926 
4927 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4928 	if (!skb) {
4929 		err = -ENOBUFS;
4930 		goto errout_ifa;
4931 	}
4932 
4933 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4934 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4935 	if (err < 0) {
4936 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4937 		WARN_ON(err == -EMSGSIZE);
4938 		kfree_skb(skb);
4939 		goto errout_ifa;
4940 	}
4941 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4942 errout_ifa:
4943 	in6_ifa_put(ifa);
4944 errout:
4945 	return err;
4946 }
4947 
4948 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4949 {
4950 	struct sk_buff *skb;
4951 	struct net *net = dev_net(ifa->idev->dev);
4952 	int err = -ENOBUFS;
4953 
4954 	/* Don't send DELADDR notification for TENTATIVE address,
4955 	 * since NEWADDR notification is sent only after removing
4956 	 * TENTATIVE flag, if DAD has not failed.
4957 	 */
4958 	if (ifa->flags & IFA_F_TENTATIVE && !(ifa->flags & IFA_F_DADFAILED) &&
4959 	    event == RTM_DELADDR)
4960 		return;
4961 
4962 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4963 	if (!skb)
4964 		goto errout;
4965 
4966 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4967 	if (err < 0) {
4968 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4969 		WARN_ON(err == -EMSGSIZE);
4970 		kfree_skb(skb);
4971 		goto errout;
4972 	}
4973 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4974 	return;
4975 errout:
4976 	if (err < 0)
4977 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4978 }
4979 
4980 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4981 				__s32 *array, int bytes)
4982 {
4983 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4984 
4985 	memset(array, 0, bytes);
4986 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4987 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4988 	array[DEVCONF_MTU6] = cnf->mtu6;
4989 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4990 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4991 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4992 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4993 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4994 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4995 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4996 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
4997 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
4998 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4999 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5000 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5001 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5002 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5003 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5004 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5005 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5006 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5007 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5008 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5009 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5010 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5011 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5012 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5013 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5014 #ifdef CONFIG_IPV6_ROUTER_PREF
5015 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5016 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5017 		jiffies_to_msecs(cnf->rtr_probe_interval);
5018 #ifdef CONFIG_IPV6_ROUTE_INFO
5019 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5020 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5021 #endif
5022 #endif
5023 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5024 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5025 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5026 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5027 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5028 #endif
5029 #ifdef CONFIG_IPV6_MROUTE
5030 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5031 #endif
5032 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5033 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5034 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5035 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5036 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5037 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5038 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5039 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5040 	/* we omit DEVCONF_STABLE_SECRET for now */
5041 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5042 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5043 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5044 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5045 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5046 #ifdef CONFIG_IPV6_SEG6_HMAC
5047 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5048 #endif
5049 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5050 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5051 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5052 }
5053 
5054 static inline size_t inet6_ifla6_size(void)
5055 {
5056 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5057 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5058 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5059 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5060 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5061 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5062 }
5063 
5064 static inline size_t inet6_if_nlmsg_size(void)
5065 {
5066 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5067 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5068 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5069 	       + nla_total_size(4) /* IFLA_MTU */
5070 	       + nla_total_size(4) /* IFLA_LINK */
5071 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5072 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5073 }
5074 
5075 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5076 					int bytes)
5077 {
5078 	int i;
5079 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5080 	BUG_ON(pad < 0);
5081 
5082 	/* Use put_unaligned() because stats may not be aligned for u64. */
5083 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5084 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5085 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5086 
5087 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5088 }
5089 
5090 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5091 					int bytes, size_t syncpoff)
5092 {
5093 	int i, c;
5094 	u64 buff[IPSTATS_MIB_MAX];
5095 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5096 
5097 	BUG_ON(pad < 0);
5098 
5099 	memset(buff, 0, sizeof(buff));
5100 	buff[0] = IPSTATS_MIB_MAX;
5101 
5102 	for_each_possible_cpu(c) {
5103 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5104 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5105 	}
5106 
5107 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5108 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5109 }
5110 
5111 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5112 			     int bytes)
5113 {
5114 	switch (attrtype) {
5115 	case IFLA_INET6_STATS:
5116 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5117 				     offsetof(struct ipstats_mib, syncp));
5118 		break;
5119 	case IFLA_INET6_ICMP6STATS:
5120 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5121 		break;
5122 	}
5123 }
5124 
5125 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5126 				  u32 ext_filter_mask)
5127 {
5128 	struct nlattr *nla;
5129 	struct ifla_cacheinfo ci;
5130 
5131 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5132 		goto nla_put_failure;
5133 	ci.max_reasm_len = IPV6_MAXPLEN;
5134 	ci.tstamp = cstamp_delta(idev->tstamp);
5135 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5136 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5137 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5138 		goto nla_put_failure;
5139 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5140 	if (!nla)
5141 		goto nla_put_failure;
5142 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5143 
5144 	/* XXX - MC not implemented */
5145 
5146 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5147 		return 0;
5148 
5149 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5150 	if (!nla)
5151 		goto nla_put_failure;
5152 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5153 
5154 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5155 	if (!nla)
5156 		goto nla_put_failure;
5157 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5158 
5159 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5160 	if (!nla)
5161 		goto nla_put_failure;
5162 
5163 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5164 		goto nla_put_failure;
5165 
5166 	read_lock_bh(&idev->lock);
5167 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5168 	read_unlock_bh(&idev->lock);
5169 
5170 	return 0;
5171 
5172 nla_put_failure:
5173 	return -EMSGSIZE;
5174 }
5175 
5176 static size_t inet6_get_link_af_size(const struct net_device *dev,
5177 				     u32 ext_filter_mask)
5178 {
5179 	if (!__in6_dev_get(dev))
5180 		return 0;
5181 
5182 	return inet6_ifla6_size();
5183 }
5184 
5185 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5186 			      u32 ext_filter_mask)
5187 {
5188 	struct inet6_dev *idev = __in6_dev_get(dev);
5189 
5190 	if (!idev)
5191 		return -ENODATA;
5192 
5193 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5194 		return -EMSGSIZE;
5195 
5196 	return 0;
5197 }
5198 
5199 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5200 {
5201 	struct inet6_ifaddr *ifp;
5202 	struct net_device *dev = idev->dev;
5203 	bool clear_token, update_rs = false;
5204 	struct in6_addr ll_addr;
5205 
5206 	ASSERT_RTNL();
5207 
5208 	if (!token)
5209 		return -EINVAL;
5210 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5211 		return -EINVAL;
5212 	if (!ipv6_accept_ra(idev))
5213 		return -EINVAL;
5214 	if (idev->cnf.rtr_solicits == 0)
5215 		return -EINVAL;
5216 
5217 	write_lock_bh(&idev->lock);
5218 
5219 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5220 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5221 
5222 	write_unlock_bh(&idev->lock);
5223 
5224 	clear_token = ipv6_addr_any(token);
5225 	if (clear_token)
5226 		goto update_lft;
5227 
5228 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5229 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5230 			     IFA_F_OPTIMISTIC)) {
5231 		/* If we're not ready, then normal ifup will take care
5232 		 * of this. Otherwise, we need to request our rs here.
5233 		 */
5234 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5235 		update_rs = true;
5236 	}
5237 
5238 update_lft:
5239 	write_lock_bh(&idev->lock);
5240 
5241 	if (update_rs) {
5242 		idev->if_flags |= IF_RS_SENT;
5243 		idev->rs_interval = rfc3315_s14_backoff_init(
5244 			idev->cnf.rtr_solicit_interval);
5245 		idev->rs_probes = 1;
5246 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5247 	}
5248 
5249 	/* Well, that's kinda nasty ... */
5250 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5251 		spin_lock(&ifp->lock);
5252 		if (ifp->tokenized) {
5253 			ifp->valid_lft = 0;
5254 			ifp->prefered_lft = 0;
5255 		}
5256 		spin_unlock(&ifp->lock);
5257 	}
5258 
5259 	write_unlock_bh(&idev->lock);
5260 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5261 	addrconf_verify_rtnl();
5262 	return 0;
5263 }
5264 
5265 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5266 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5267 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5268 };
5269 
5270 static int inet6_validate_link_af(const struct net_device *dev,
5271 				  const struct nlattr *nla)
5272 {
5273 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5274 
5275 	if (dev && !__in6_dev_get(dev))
5276 		return -EAFNOSUPPORT;
5277 
5278 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5279 				NULL);
5280 }
5281 
5282 static int check_addr_gen_mode(int mode)
5283 {
5284 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5285 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5286 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5287 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5288 		return -EINVAL;
5289 	return 1;
5290 }
5291 
5292 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5293 				int mode)
5294 {
5295 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5296 	    !idev->cnf.stable_secret.initialized &&
5297 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5298 		return -EINVAL;
5299 	return 1;
5300 }
5301 
5302 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5303 {
5304 	int err = -EINVAL;
5305 	struct inet6_dev *idev = __in6_dev_get(dev);
5306 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5307 
5308 	if (!idev)
5309 		return -EAFNOSUPPORT;
5310 
5311 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5312 		BUG();
5313 
5314 	if (tb[IFLA_INET6_TOKEN]) {
5315 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5316 		if (err)
5317 			return err;
5318 	}
5319 
5320 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5321 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5322 
5323 		if (check_addr_gen_mode(mode) < 0 ||
5324 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5325 			return -EINVAL;
5326 
5327 		idev->cnf.addr_gen_mode = mode;
5328 		err = 0;
5329 	}
5330 
5331 	return err;
5332 }
5333 
5334 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5335 			     u32 portid, u32 seq, int event, unsigned int flags)
5336 {
5337 	struct net_device *dev = idev->dev;
5338 	struct ifinfomsg *hdr;
5339 	struct nlmsghdr *nlh;
5340 	void *protoinfo;
5341 
5342 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5343 	if (!nlh)
5344 		return -EMSGSIZE;
5345 
5346 	hdr = nlmsg_data(nlh);
5347 	hdr->ifi_family = AF_INET6;
5348 	hdr->__ifi_pad = 0;
5349 	hdr->ifi_type = dev->type;
5350 	hdr->ifi_index = dev->ifindex;
5351 	hdr->ifi_flags = dev_get_flags(dev);
5352 	hdr->ifi_change = 0;
5353 
5354 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5355 	    (dev->addr_len &&
5356 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5357 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5358 	    (dev->ifindex != dev_get_iflink(dev) &&
5359 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5360 	    nla_put_u8(skb, IFLA_OPERSTATE,
5361 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5362 		goto nla_put_failure;
5363 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5364 	if (!protoinfo)
5365 		goto nla_put_failure;
5366 
5367 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5368 		goto nla_put_failure;
5369 
5370 	nla_nest_end(skb, protoinfo);
5371 	nlmsg_end(skb, nlh);
5372 	return 0;
5373 
5374 nla_put_failure:
5375 	nlmsg_cancel(skb, nlh);
5376 	return -EMSGSIZE;
5377 }
5378 
5379 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5380 {
5381 	struct net *net = sock_net(skb->sk);
5382 	int h, s_h;
5383 	int idx = 0, s_idx;
5384 	struct net_device *dev;
5385 	struct inet6_dev *idev;
5386 	struct hlist_head *head;
5387 
5388 	s_h = cb->args[0];
5389 	s_idx = cb->args[1];
5390 
5391 	rcu_read_lock();
5392 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5393 		idx = 0;
5394 		head = &net->dev_index_head[h];
5395 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5396 			if (idx < s_idx)
5397 				goto cont;
5398 			idev = __in6_dev_get(dev);
5399 			if (!idev)
5400 				goto cont;
5401 			if (inet6_fill_ifinfo(skb, idev,
5402 					      NETLINK_CB(cb->skb).portid,
5403 					      cb->nlh->nlmsg_seq,
5404 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5405 				goto out;
5406 cont:
5407 			idx++;
5408 		}
5409 	}
5410 out:
5411 	rcu_read_unlock();
5412 	cb->args[1] = idx;
5413 	cb->args[0] = h;
5414 
5415 	return skb->len;
5416 }
5417 
5418 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5419 {
5420 	struct sk_buff *skb;
5421 	struct net *net = dev_net(idev->dev);
5422 	int err = -ENOBUFS;
5423 
5424 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5425 	if (!skb)
5426 		goto errout;
5427 
5428 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5429 	if (err < 0) {
5430 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5431 		WARN_ON(err == -EMSGSIZE);
5432 		kfree_skb(skb);
5433 		goto errout;
5434 	}
5435 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5436 	return;
5437 errout:
5438 	if (err < 0)
5439 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5440 }
5441 
5442 static inline size_t inet6_prefix_nlmsg_size(void)
5443 {
5444 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5445 	       + nla_total_size(sizeof(struct in6_addr))
5446 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5447 }
5448 
5449 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5450 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5451 			     int event, unsigned int flags)
5452 {
5453 	struct prefixmsg *pmsg;
5454 	struct nlmsghdr *nlh;
5455 	struct prefix_cacheinfo	ci;
5456 
5457 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5458 	if (!nlh)
5459 		return -EMSGSIZE;
5460 
5461 	pmsg = nlmsg_data(nlh);
5462 	pmsg->prefix_family = AF_INET6;
5463 	pmsg->prefix_pad1 = 0;
5464 	pmsg->prefix_pad2 = 0;
5465 	pmsg->prefix_ifindex = idev->dev->ifindex;
5466 	pmsg->prefix_len = pinfo->prefix_len;
5467 	pmsg->prefix_type = pinfo->type;
5468 	pmsg->prefix_pad3 = 0;
5469 	pmsg->prefix_flags = 0;
5470 	if (pinfo->onlink)
5471 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5472 	if (pinfo->autoconf)
5473 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5474 
5475 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5476 		goto nla_put_failure;
5477 	ci.preferred_time = ntohl(pinfo->prefered);
5478 	ci.valid_time = ntohl(pinfo->valid);
5479 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5480 		goto nla_put_failure;
5481 	nlmsg_end(skb, nlh);
5482 	return 0;
5483 
5484 nla_put_failure:
5485 	nlmsg_cancel(skb, nlh);
5486 	return -EMSGSIZE;
5487 }
5488 
5489 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5490 			 struct prefix_info *pinfo)
5491 {
5492 	struct sk_buff *skb;
5493 	struct net *net = dev_net(idev->dev);
5494 	int err = -ENOBUFS;
5495 
5496 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5497 	if (!skb)
5498 		goto errout;
5499 
5500 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5501 	if (err < 0) {
5502 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5503 		WARN_ON(err == -EMSGSIZE);
5504 		kfree_skb(skb);
5505 		goto errout;
5506 	}
5507 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5508 	return;
5509 errout:
5510 	if (err < 0)
5511 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5512 }
5513 
5514 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5515 {
5516 	struct net *net = dev_net(ifp->idev->dev);
5517 
5518 	if (event)
5519 		ASSERT_RTNL();
5520 
5521 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5522 
5523 	switch (event) {
5524 	case RTM_NEWADDR:
5525 		/*
5526 		 * If the address was optimistic
5527 		 * we inserted the route at the start of
5528 		 * our DAD process, so we don't need
5529 		 * to do it again
5530 		 */
5531 		if (!rcu_access_pointer(ifp->rt->rt6i_node))
5532 			ip6_ins_rt(ifp->rt);
5533 		if (ifp->idev->cnf.forwarding)
5534 			addrconf_join_anycast(ifp);
5535 		if (!ipv6_addr_any(&ifp->peer_addr))
5536 			addrconf_prefix_route(&ifp->peer_addr, 128,
5537 					      ifp->idev->dev, 0, 0);
5538 		break;
5539 	case RTM_DELADDR:
5540 		if (ifp->idev->cnf.forwarding)
5541 			addrconf_leave_anycast(ifp);
5542 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5543 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5544 			struct rt6_info *rt;
5545 
5546 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5547 						       ifp->idev->dev, 0, 0);
5548 			if (rt)
5549 				ip6_del_rt(rt);
5550 		}
5551 		if (ifp->rt) {
5552 			if (dst_hold_safe(&ifp->rt->dst))
5553 				ip6_del_rt(ifp->rt);
5554 		}
5555 		rt_genid_bump_ipv6(net);
5556 		break;
5557 	}
5558 	atomic_inc(&net->ipv6.dev_addr_genid);
5559 }
5560 
5561 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5562 {
5563 	rcu_read_lock_bh();
5564 	if (likely(ifp->idev->dead == 0))
5565 		__ipv6_ifa_notify(event, ifp);
5566 	rcu_read_unlock_bh();
5567 }
5568 
5569 #ifdef CONFIG_SYSCTL
5570 
5571 static
5572 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5573 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5574 {
5575 	int *valp = ctl->data;
5576 	int val = *valp;
5577 	loff_t pos = *ppos;
5578 	struct ctl_table lctl;
5579 	int ret;
5580 
5581 	/*
5582 	 * ctl->data points to idev->cnf.forwarding, we should
5583 	 * not modify it until we get the rtnl lock.
5584 	 */
5585 	lctl = *ctl;
5586 	lctl.data = &val;
5587 
5588 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5589 
5590 	if (write)
5591 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5592 	if (ret)
5593 		*ppos = pos;
5594 	return ret;
5595 }
5596 
5597 static
5598 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5599 			void __user *buffer, size_t *lenp, loff_t *ppos)
5600 {
5601 	struct inet6_dev *idev = ctl->extra1;
5602 	int min_mtu = IPV6_MIN_MTU;
5603 	struct ctl_table lctl;
5604 
5605 	lctl = *ctl;
5606 	lctl.extra1 = &min_mtu;
5607 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5608 
5609 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5610 }
5611 
5612 static void dev_disable_change(struct inet6_dev *idev)
5613 {
5614 	struct netdev_notifier_info info;
5615 
5616 	if (!idev || !idev->dev)
5617 		return;
5618 
5619 	netdev_notifier_info_init(&info, idev->dev);
5620 	if (idev->cnf.disable_ipv6)
5621 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5622 	else
5623 		addrconf_notify(NULL, NETDEV_UP, &info);
5624 }
5625 
5626 static void addrconf_disable_change(struct net *net, __s32 newf)
5627 {
5628 	struct net_device *dev;
5629 	struct inet6_dev *idev;
5630 
5631 	for_each_netdev(net, dev) {
5632 		idev = __in6_dev_get(dev);
5633 		if (idev) {
5634 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5635 			idev->cnf.disable_ipv6 = newf;
5636 			if (changed)
5637 				dev_disable_change(idev);
5638 		}
5639 	}
5640 }
5641 
5642 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5643 {
5644 	struct net *net;
5645 	int old;
5646 
5647 	if (!rtnl_trylock())
5648 		return restart_syscall();
5649 
5650 	net = (struct net *)table->extra2;
5651 	old = *p;
5652 	*p = newf;
5653 
5654 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5655 		rtnl_unlock();
5656 		return 0;
5657 	}
5658 
5659 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5660 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5661 		addrconf_disable_change(net, newf);
5662 	} else if ((!newf) ^ (!old))
5663 		dev_disable_change((struct inet6_dev *)table->extra1);
5664 
5665 	rtnl_unlock();
5666 	return 0;
5667 }
5668 
5669 static
5670 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5671 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5672 {
5673 	int *valp = ctl->data;
5674 	int val = *valp;
5675 	loff_t pos = *ppos;
5676 	struct ctl_table lctl;
5677 	int ret;
5678 
5679 	/*
5680 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5681 	 * not modify it until we get the rtnl lock.
5682 	 */
5683 	lctl = *ctl;
5684 	lctl.data = &val;
5685 
5686 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5687 
5688 	if (write)
5689 		ret = addrconf_disable_ipv6(ctl, valp, val);
5690 	if (ret)
5691 		*ppos = pos;
5692 	return ret;
5693 }
5694 
5695 static
5696 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5697 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5698 {
5699 	int *valp = ctl->data;
5700 	int ret;
5701 	int old, new;
5702 
5703 	old = *valp;
5704 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5705 	new = *valp;
5706 
5707 	if (write && old != new) {
5708 		struct net *net = ctl->extra2;
5709 
5710 		if (!rtnl_trylock())
5711 			return restart_syscall();
5712 
5713 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5714 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5715 						     NETCONFA_PROXY_NEIGH,
5716 						     NETCONFA_IFINDEX_DEFAULT,
5717 						     net->ipv6.devconf_dflt);
5718 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5719 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5720 						     NETCONFA_PROXY_NEIGH,
5721 						     NETCONFA_IFINDEX_ALL,
5722 						     net->ipv6.devconf_all);
5723 		else {
5724 			struct inet6_dev *idev = ctl->extra1;
5725 
5726 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5727 						     NETCONFA_PROXY_NEIGH,
5728 						     idev->dev->ifindex,
5729 						     &idev->cnf);
5730 		}
5731 		rtnl_unlock();
5732 	}
5733 
5734 	return ret;
5735 }
5736 
5737 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5738 					 void __user *buffer, size_t *lenp,
5739 					 loff_t *ppos)
5740 {
5741 	int ret = 0;
5742 	int new_val;
5743 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5744 	struct net *net = (struct net *)ctl->extra2;
5745 
5746 	if (!rtnl_trylock())
5747 		return restart_syscall();
5748 
5749 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5750 
5751 	if (write) {
5752 		new_val = *((int *)ctl->data);
5753 
5754 		if (check_addr_gen_mode(new_val) < 0) {
5755 			ret = -EINVAL;
5756 			goto out;
5757 		}
5758 
5759 		/* request for default */
5760 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5761 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5762 
5763 		/* request for individual net device */
5764 		} else {
5765 			if (!idev)
5766 				goto out;
5767 
5768 			if (check_stable_privacy(idev, net, new_val) < 0) {
5769 				ret = -EINVAL;
5770 				goto out;
5771 			}
5772 
5773 			if (idev->cnf.addr_gen_mode != new_val) {
5774 				idev->cnf.addr_gen_mode = new_val;
5775 				addrconf_dev_config(idev->dev);
5776 			}
5777 		}
5778 	}
5779 
5780 out:
5781 	rtnl_unlock();
5782 
5783 	return ret;
5784 }
5785 
5786 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5787 					 void __user *buffer, size_t *lenp,
5788 					 loff_t *ppos)
5789 {
5790 	int err;
5791 	struct in6_addr addr;
5792 	char str[IPV6_MAX_STRLEN];
5793 	struct ctl_table lctl = *ctl;
5794 	struct net *net = ctl->extra2;
5795 	struct ipv6_stable_secret *secret = ctl->data;
5796 
5797 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5798 		return -EIO;
5799 
5800 	lctl.maxlen = IPV6_MAX_STRLEN;
5801 	lctl.data = str;
5802 
5803 	if (!rtnl_trylock())
5804 		return restart_syscall();
5805 
5806 	if (!write && !secret->initialized) {
5807 		err = -EIO;
5808 		goto out;
5809 	}
5810 
5811 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5812 	if (err >= sizeof(str)) {
5813 		err = -EIO;
5814 		goto out;
5815 	}
5816 
5817 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5818 	if (err || !write)
5819 		goto out;
5820 
5821 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5822 		err = -EIO;
5823 		goto out;
5824 	}
5825 
5826 	secret->initialized = true;
5827 	secret->secret = addr;
5828 
5829 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5830 		struct net_device *dev;
5831 
5832 		for_each_netdev(net, dev) {
5833 			struct inet6_dev *idev = __in6_dev_get(dev);
5834 
5835 			if (idev) {
5836 				idev->cnf.addr_gen_mode =
5837 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5838 			}
5839 		}
5840 	} else {
5841 		struct inet6_dev *idev = ctl->extra1;
5842 
5843 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5844 	}
5845 
5846 out:
5847 	rtnl_unlock();
5848 
5849 	return err;
5850 }
5851 
5852 static
5853 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5854 						int write,
5855 						void __user *buffer,
5856 						size_t *lenp,
5857 						loff_t *ppos)
5858 {
5859 	int *valp = ctl->data;
5860 	int val = *valp;
5861 	loff_t pos = *ppos;
5862 	struct ctl_table lctl;
5863 	int ret;
5864 
5865 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5866 	 * we should not modify it until we get the rtnl lock.
5867 	 */
5868 	lctl = *ctl;
5869 	lctl.data = &val;
5870 
5871 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5872 
5873 	if (write)
5874 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5875 	if (ret)
5876 		*ppos = pos;
5877 	return ret;
5878 }
5879 
5880 static
5881 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5882 {
5883 	if (rt) {
5884 		if (action)
5885 			rt->dst.flags |= DST_NOPOLICY;
5886 		else
5887 			rt->dst.flags &= ~DST_NOPOLICY;
5888 	}
5889 }
5890 
5891 static
5892 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5893 {
5894 	struct inet6_ifaddr *ifa;
5895 
5896 	read_lock_bh(&idev->lock);
5897 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5898 		spin_lock(&ifa->lock);
5899 		if (ifa->rt) {
5900 			struct rt6_info *rt = ifa->rt;
5901 			struct fib6_table *table = rt->rt6i_table;
5902 			int cpu;
5903 
5904 			read_lock(&table->tb6_lock);
5905 			addrconf_set_nopolicy(ifa->rt, val);
5906 			if (rt->rt6i_pcpu) {
5907 				for_each_possible_cpu(cpu) {
5908 					struct rt6_info **rtp;
5909 
5910 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5911 					addrconf_set_nopolicy(*rtp, val);
5912 				}
5913 			}
5914 			read_unlock(&table->tb6_lock);
5915 		}
5916 		spin_unlock(&ifa->lock);
5917 	}
5918 	read_unlock_bh(&idev->lock);
5919 }
5920 
5921 static
5922 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
5923 {
5924 	struct inet6_dev *idev;
5925 	struct net *net;
5926 
5927 	if (!rtnl_trylock())
5928 		return restart_syscall();
5929 
5930 	*valp = val;
5931 
5932 	net = (struct net *)ctl->extra2;
5933 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
5934 		rtnl_unlock();
5935 		return 0;
5936 	}
5937 
5938 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
5939 		struct net_device *dev;
5940 
5941 		for_each_netdev(net, dev) {
5942 			idev = __in6_dev_get(dev);
5943 			if (idev)
5944 				addrconf_disable_policy_idev(idev, val);
5945 		}
5946 	} else {
5947 		idev = (struct inet6_dev *)ctl->extra1;
5948 		addrconf_disable_policy_idev(idev, val);
5949 	}
5950 
5951 	rtnl_unlock();
5952 	return 0;
5953 }
5954 
5955 static
5956 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
5957 				   void __user *buffer, size_t *lenp,
5958 				   loff_t *ppos)
5959 {
5960 	int *valp = ctl->data;
5961 	int val = *valp;
5962 	loff_t pos = *ppos;
5963 	struct ctl_table lctl;
5964 	int ret;
5965 
5966 	lctl = *ctl;
5967 	lctl.data = &val;
5968 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5969 
5970 	if (write && (*valp != val))
5971 		ret = addrconf_disable_policy(ctl, valp, val);
5972 
5973 	if (ret)
5974 		*ppos = pos;
5975 
5976 	return ret;
5977 }
5978 
5979 static int minus_one = -1;
5980 static const int one = 1;
5981 static const int two_five_five = 255;
5982 
5983 static const struct ctl_table addrconf_sysctl[] = {
5984 	{
5985 		.procname	= "forwarding",
5986 		.data		= &ipv6_devconf.forwarding,
5987 		.maxlen		= sizeof(int),
5988 		.mode		= 0644,
5989 		.proc_handler	= addrconf_sysctl_forward,
5990 	},
5991 	{
5992 		.procname	= "hop_limit",
5993 		.data		= &ipv6_devconf.hop_limit,
5994 		.maxlen		= sizeof(int),
5995 		.mode		= 0644,
5996 		.proc_handler	= proc_dointvec_minmax,
5997 		.extra1		= (void *)&one,
5998 		.extra2		= (void *)&two_five_five,
5999 	},
6000 	{
6001 		.procname	= "mtu",
6002 		.data		= &ipv6_devconf.mtu6,
6003 		.maxlen		= sizeof(int),
6004 		.mode		= 0644,
6005 		.proc_handler	= addrconf_sysctl_mtu,
6006 	},
6007 	{
6008 		.procname	= "accept_ra",
6009 		.data		= &ipv6_devconf.accept_ra,
6010 		.maxlen		= sizeof(int),
6011 		.mode		= 0644,
6012 		.proc_handler	= proc_dointvec,
6013 	},
6014 	{
6015 		.procname	= "accept_redirects",
6016 		.data		= &ipv6_devconf.accept_redirects,
6017 		.maxlen		= sizeof(int),
6018 		.mode		= 0644,
6019 		.proc_handler	= proc_dointvec,
6020 	},
6021 	{
6022 		.procname	= "autoconf",
6023 		.data		= &ipv6_devconf.autoconf,
6024 		.maxlen		= sizeof(int),
6025 		.mode		= 0644,
6026 		.proc_handler	= proc_dointvec,
6027 	},
6028 	{
6029 		.procname	= "dad_transmits",
6030 		.data		= &ipv6_devconf.dad_transmits,
6031 		.maxlen		= sizeof(int),
6032 		.mode		= 0644,
6033 		.proc_handler	= proc_dointvec,
6034 	},
6035 	{
6036 		.procname	= "router_solicitations",
6037 		.data		= &ipv6_devconf.rtr_solicits,
6038 		.maxlen		= sizeof(int),
6039 		.mode		= 0644,
6040 		.proc_handler	= proc_dointvec_minmax,
6041 		.extra1		= &minus_one,
6042 	},
6043 	{
6044 		.procname	= "router_solicitation_interval",
6045 		.data		= &ipv6_devconf.rtr_solicit_interval,
6046 		.maxlen		= sizeof(int),
6047 		.mode		= 0644,
6048 		.proc_handler	= proc_dointvec_jiffies,
6049 	},
6050 	{
6051 		.procname	= "router_solicitation_max_interval",
6052 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6053 		.maxlen		= sizeof(int),
6054 		.mode		= 0644,
6055 		.proc_handler	= proc_dointvec_jiffies,
6056 	},
6057 	{
6058 		.procname	= "router_solicitation_delay",
6059 		.data		= &ipv6_devconf.rtr_solicit_delay,
6060 		.maxlen		= sizeof(int),
6061 		.mode		= 0644,
6062 		.proc_handler	= proc_dointvec_jiffies,
6063 	},
6064 	{
6065 		.procname	= "force_mld_version",
6066 		.data		= &ipv6_devconf.force_mld_version,
6067 		.maxlen		= sizeof(int),
6068 		.mode		= 0644,
6069 		.proc_handler	= proc_dointvec,
6070 	},
6071 	{
6072 		.procname	= "mldv1_unsolicited_report_interval",
6073 		.data		=
6074 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6075 		.maxlen		= sizeof(int),
6076 		.mode		= 0644,
6077 		.proc_handler	= proc_dointvec_ms_jiffies,
6078 	},
6079 	{
6080 		.procname	= "mldv2_unsolicited_report_interval",
6081 		.data		=
6082 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6083 		.maxlen		= sizeof(int),
6084 		.mode		= 0644,
6085 		.proc_handler	= proc_dointvec_ms_jiffies,
6086 	},
6087 	{
6088 		.procname	= "use_tempaddr",
6089 		.data		= &ipv6_devconf.use_tempaddr,
6090 		.maxlen		= sizeof(int),
6091 		.mode		= 0644,
6092 		.proc_handler	= proc_dointvec,
6093 	},
6094 	{
6095 		.procname	= "temp_valid_lft",
6096 		.data		= &ipv6_devconf.temp_valid_lft,
6097 		.maxlen		= sizeof(int),
6098 		.mode		= 0644,
6099 		.proc_handler	= proc_dointvec,
6100 	},
6101 	{
6102 		.procname	= "temp_prefered_lft",
6103 		.data		= &ipv6_devconf.temp_prefered_lft,
6104 		.maxlen		= sizeof(int),
6105 		.mode		= 0644,
6106 		.proc_handler	= proc_dointvec,
6107 	},
6108 	{
6109 		.procname	= "regen_max_retry",
6110 		.data		= &ipv6_devconf.regen_max_retry,
6111 		.maxlen		= sizeof(int),
6112 		.mode		= 0644,
6113 		.proc_handler	= proc_dointvec,
6114 	},
6115 	{
6116 		.procname	= "max_desync_factor",
6117 		.data		= &ipv6_devconf.max_desync_factor,
6118 		.maxlen		= sizeof(int),
6119 		.mode		= 0644,
6120 		.proc_handler	= proc_dointvec,
6121 	},
6122 	{
6123 		.procname	= "max_addresses",
6124 		.data		= &ipv6_devconf.max_addresses,
6125 		.maxlen		= sizeof(int),
6126 		.mode		= 0644,
6127 		.proc_handler	= proc_dointvec,
6128 	},
6129 	{
6130 		.procname	= "accept_ra_defrtr",
6131 		.data		= &ipv6_devconf.accept_ra_defrtr,
6132 		.maxlen		= sizeof(int),
6133 		.mode		= 0644,
6134 		.proc_handler	= proc_dointvec,
6135 	},
6136 	{
6137 		.procname	= "accept_ra_min_hop_limit",
6138 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6139 		.maxlen		= sizeof(int),
6140 		.mode		= 0644,
6141 		.proc_handler	= proc_dointvec,
6142 	},
6143 	{
6144 		.procname	= "accept_ra_pinfo",
6145 		.data		= &ipv6_devconf.accept_ra_pinfo,
6146 		.maxlen		= sizeof(int),
6147 		.mode		= 0644,
6148 		.proc_handler	= proc_dointvec,
6149 	},
6150 #ifdef CONFIG_IPV6_ROUTER_PREF
6151 	{
6152 		.procname	= "accept_ra_rtr_pref",
6153 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6154 		.maxlen		= sizeof(int),
6155 		.mode		= 0644,
6156 		.proc_handler	= proc_dointvec,
6157 	},
6158 	{
6159 		.procname	= "router_probe_interval",
6160 		.data		= &ipv6_devconf.rtr_probe_interval,
6161 		.maxlen		= sizeof(int),
6162 		.mode		= 0644,
6163 		.proc_handler	= proc_dointvec_jiffies,
6164 	},
6165 #ifdef CONFIG_IPV6_ROUTE_INFO
6166 	{
6167 		.procname	= "accept_ra_rt_info_min_plen",
6168 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6169 		.maxlen		= sizeof(int),
6170 		.mode		= 0644,
6171 		.proc_handler	= proc_dointvec,
6172 	},
6173 	{
6174 		.procname	= "accept_ra_rt_info_max_plen",
6175 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6176 		.maxlen		= sizeof(int),
6177 		.mode		= 0644,
6178 		.proc_handler	= proc_dointvec,
6179 	},
6180 #endif
6181 #endif
6182 	{
6183 		.procname	= "proxy_ndp",
6184 		.data		= &ipv6_devconf.proxy_ndp,
6185 		.maxlen		= sizeof(int),
6186 		.mode		= 0644,
6187 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6188 	},
6189 	{
6190 		.procname	= "accept_source_route",
6191 		.data		= &ipv6_devconf.accept_source_route,
6192 		.maxlen		= sizeof(int),
6193 		.mode		= 0644,
6194 		.proc_handler	= proc_dointvec,
6195 	},
6196 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6197 	{
6198 		.procname	= "optimistic_dad",
6199 		.data		= &ipv6_devconf.optimistic_dad,
6200 		.maxlen		= sizeof(int),
6201 		.mode		= 0644,
6202 		.proc_handler   = proc_dointvec,
6203 	},
6204 	{
6205 		.procname	= "use_optimistic",
6206 		.data		= &ipv6_devconf.use_optimistic,
6207 		.maxlen		= sizeof(int),
6208 		.mode		= 0644,
6209 		.proc_handler	= proc_dointvec,
6210 	},
6211 #endif
6212 #ifdef CONFIG_IPV6_MROUTE
6213 	{
6214 		.procname	= "mc_forwarding",
6215 		.data		= &ipv6_devconf.mc_forwarding,
6216 		.maxlen		= sizeof(int),
6217 		.mode		= 0444,
6218 		.proc_handler	= proc_dointvec,
6219 	},
6220 #endif
6221 	{
6222 		.procname	= "disable_ipv6",
6223 		.data		= &ipv6_devconf.disable_ipv6,
6224 		.maxlen		= sizeof(int),
6225 		.mode		= 0644,
6226 		.proc_handler	= addrconf_sysctl_disable,
6227 	},
6228 	{
6229 		.procname	= "accept_dad",
6230 		.data		= &ipv6_devconf.accept_dad,
6231 		.maxlen		= sizeof(int),
6232 		.mode		= 0644,
6233 		.proc_handler	= proc_dointvec,
6234 	},
6235 	{
6236 		.procname	= "force_tllao",
6237 		.data		= &ipv6_devconf.force_tllao,
6238 		.maxlen		= sizeof(int),
6239 		.mode		= 0644,
6240 		.proc_handler	= proc_dointvec
6241 	},
6242 	{
6243 		.procname	= "ndisc_notify",
6244 		.data		= &ipv6_devconf.ndisc_notify,
6245 		.maxlen		= sizeof(int),
6246 		.mode		= 0644,
6247 		.proc_handler	= proc_dointvec
6248 	},
6249 	{
6250 		.procname	= "suppress_frag_ndisc",
6251 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6252 		.maxlen		= sizeof(int),
6253 		.mode		= 0644,
6254 		.proc_handler	= proc_dointvec
6255 	},
6256 	{
6257 		.procname	= "accept_ra_from_local",
6258 		.data		= &ipv6_devconf.accept_ra_from_local,
6259 		.maxlen		= sizeof(int),
6260 		.mode		= 0644,
6261 		.proc_handler	= proc_dointvec,
6262 	},
6263 	{
6264 		.procname	= "accept_ra_mtu",
6265 		.data		= &ipv6_devconf.accept_ra_mtu,
6266 		.maxlen		= sizeof(int),
6267 		.mode		= 0644,
6268 		.proc_handler	= proc_dointvec,
6269 	},
6270 	{
6271 		.procname	= "stable_secret",
6272 		.data		= &ipv6_devconf.stable_secret,
6273 		.maxlen		= IPV6_MAX_STRLEN,
6274 		.mode		= 0600,
6275 		.proc_handler	= addrconf_sysctl_stable_secret,
6276 	},
6277 	{
6278 		.procname	= "use_oif_addrs_only",
6279 		.data		= &ipv6_devconf.use_oif_addrs_only,
6280 		.maxlen		= sizeof(int),
6281 		.mode		= 0644,
6282 		.proc_handler	= proc_dointvec,
6283 	},
6284 	{
6285 		.procname	= "ignore_routes_with_linkdown",
6286 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6287 		.maxlen		= sizeof(int),
6288 		.mode		= 0644,
6289 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6290 	},
6291 	{
6292 		.procname	= "drop_unicast_in_l2_multicast",
6293 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6294 		.maxlen		= sizeof(int),
6295 		.mode		= 0644,
6296 		.proc_handler	= proc_dointvec,
6297 	},
6298 	{
6299 		.procname	= "drop_unsolicited_na",
6300 		.data		= &ipv6_devconf.drop_unsolicited_na,
6301 		.maxlen		= sizeof(int),
6302 		.mode		= 0644,
6303 		.proc_handler	= proc_dointvec,
6304 	},
6305 	{
6306 		.procname	= "keep_addr_on_down",
6307 		.data		= &ipv6_devconf.keep_addr_on_down,
6308 		.maxlen		= sizeof(int),
6309 		.mode		= 0644,
6310 		.proc_handler	= proc_dointvec,
6311 
6312 	},
6313 	{
6314 		.procname	= "seg6_enabled",
6315 		.data		= &ipv6_devconf.seg6_enabled,
6316 		.maxlen		= sizeof(int),
6317 		.mode		= 0644,
6318 		.proc_handler	= proc_dointvec,
6319 	},
6320 #ifdef CONFIG_IPV6_SEG6_HMAC
6321 	{
6322 		.procname	= "seg6_require_hmac",
6323 		.data		= &ipv6_devconf.seg6_require_hmac,
6324 		.maxlen		= sizeof(int),
6325 		.mode		= 0644,
6326 		.proc_handler	= proc_dointvec,
6327 	},
6328 #endif
6329 	{
6330 		.procname       = "enhanced_dad",
6331 		.data           = &ipv6_devconf.enhanced_dad,
6332 		.maxlen         = sizeof(int),
6333 		.mode           = 0644,
6334 		.proc_handler   = proc_dointvec,
6335 	},
6336 	{
6337 		.procname		= "addr_gen_mode",
6338 		.data			= &ipv6_devconf.addr_gen_mode,
6339 		.maxlen			= sizeof(int),
6340 		.mode			= 0644,
6341 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6342 	},
6343 	{
6344 		.procname       = "disable_policy",
6345 		.data           = &ipv6_devconf.disable_policy,
6346 		.maxlen         = sizeof(int),
6347 		.mode           = 0644,
6348 		.proc_handler   = addrconf_sysctl_disable_policy,
6349 	},
6350 	{
6351 		/* sentinel */
6352 	}
6353 };
6354 
6355 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6356 		struct inet6_dev *idev, struct ipv6_devconf *p)
6357 {
6358 	int i, ifindex;
6359 	struct ctl_table *table;
6360 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6361 
6362 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6363 	if (!table)
6364 		goto out;
6365 
6366 	for (i = 0; table[i].data; i++) {
6367 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6368 		/* If one of these is already set, then it is not safe to
6369 		 * overwrite either of them: this makes proc_dointvec_minmax
6370 		 * usable.
6371 		 */
6372 		if (!table[i].extra1 && !table[i].extra2) {
6373 			table[i].extra1 = idev; /* embedded; no ref */
6374 			table[i].extra2 = net;
6375 		}
6376 	}
6377 
6378 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6379 
6380 	p->sysctl_header = register_net_sysctl(net, path, table);
6381 	if (!p->sysctl_header)
6382 		goto free;
6383 
6384 	if (!strcmp(dev_name, "all"))
6385 		ifindex = NETCONFA_IFINDEX_ALL;
6386 	else if (!strcmp(dev_name, "default"))
6387 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6388 	else
6389 		ifindex = idev->dev->ifindex;
6390 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6391 				     ifindex, p);
6392 	return 0;
6393 
6394 free:
6395 	kfree(table);
6396 out:
6397 	return -ENOBUFS;
6398 }
6399 
6400 static void __addrconf_sysctl_unregister(struct net *net,
6401 					 struct ipv6_devconf *p, int ifindex)
6402 {
6403 	struct ctl_table *table;
6404 
6405 	if (!p->sysctl_header)
6406 		return;
6407 
6408 	table = p->sysctl_header->ctl_table_arg;
6409 	unregister_net_sysctl_table(p->sysctl_header);
6410 	p->sysctl_header = NULL;
6411 	kfree(table);
6412 
6413 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6414 }
6415 
6416 static int addrconf_sysctl_register(struct inet6_dev *idev)
6417 {
6418 	int err;
6419 
6420 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6421 		return -EINVAL;
6422 
6423 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6424 				    &ndisc_ifinfo_sysctl_change);
6425 	if (err)
6426 		return err;
6427 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6428 					 idev, &idev->cnf);
6429 	if (err)
6430 		neigh_sysctl_unregister(idev->nd_parms);
6431 
6432 	return err;
6433 }
6434 
6435 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6436 {
6437 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6438 				     idev->dev->ifindex);
6439 	neigh_sysctl_unregister(idev->nd_parms);
6440 }
6441 
6442 
6443 #endif
6444 
6445 static int __net_init addrconf_init_net(struct net *net)
6446 {
6447 	int err = -ENOMEM;
6448 	struct ipv6_devconf *all, *dflt;
6449 
6450 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6451 	if (!all)
6452 		goto err_alloc_all;
6453 
6454 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6455 	if (!dflt)
6456 		goto err_alloc_dflt;
6457 
6458 	/* these will be inherited by all namespaces */
6459 	dflt->autoconf = ipv6_defaults.autoconf;
6460 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6461 
6462 	dflt->stable_secret.initialized = false;
6463 	all->stable_secret.initialized = false;
6464 
6465 	net->ipv6.devconf_all = all;
6466 	net->ipv6.devconf_dflt = dflt;
6467 
6468 #ifdef CONFIG_SYSCTL
6469 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6470 	if (err < 0)
6471 		goto err_reg_all;
6472 
6473 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6474 	if (err < 0)
6475 		goto err_reg_dflt;
6476 #endif
6477 	return 0;
6478 
6479 #ifdef CONFIG_SYSCTL
6480 err_reg_dflt:
6481 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6482 err_reg_all:
6483 	kfree(dflt);
6484 #endif
6485 err_alloc_dflt:
6486 	kfree(all);
6487 err_alloc_all:
6488 	return err;
6489 }
6490 
6491 static void __net_exit addrconf_exit_net(struct net *net)
6492 {
6493 #ifdef CONFIG_SYSCTL
6494 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6495 				     NETCONFA_IFINDEX_DEFAULT);
6496 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6497 				     NETCONFA_IFINDEX_ALL);
6498 #endif
6499 	kfree(net->ipv6.devconf_dflt);
6500 	kfree(net->ipv6.devconf_all);
6501 }
6502 
6503 static struct pernet_operations addrconf_ops = {
6504 	.init = addrconf_init_net,
6505 	.exit = addrconf_exit_net,
6506 };
6507 
6508 static struct rtnl_af_ops inet6_ops __read_mostly = {
6509 	.family		  = AF_INET6,
6510 	.fill_link_af	  = inet6_fill_link_af,
6511 	.get_link_af_size = inet6_get_link_af_size,
6512 	.validate_link_af = inet6_validate_link_af,
6513 	.set_link_af	  = inet6_set_link_af,
6514 };
6515 
6516 /*
6517  *	Init / cleanup code
6518  */
6519 
6520 int __init addrconf_init(void)
6521 {
6522 	struct inet6_dev *idev;
6523 	int i, err;
6524 
6525 	err = ipv6_addr_label_init();
6526 	if (err < 0) {
6527 		pr_crit("%s: cannot initialize default policy table: %d\n",
6528 			__func__, err);
6529 		goto out;
6530 	}
6531 
6532 	err = register_pernet_subsys(&addrconf_ops);
6533 	if (err < 0)
6534 		goto out_addrlabel;
6535 
6536 	addrconf_wq = create_workqueue("ipv6_addrconf");
6537 	if (!addrconf_wq) {
6538 		err = -ENOMEM;
6539 		goto out_nowq;
6540 	}
6541 
6542 	/* The addrconf netdev notifier requires that loopback_dev
6543 	 * has it's ipv6 private information allocated and setup
6544 	 * before it can bring up and give link-local addresses
6545 	 * to other devices which are up.
6546 	 *
6547 	 * Unfortunately, loopback_dev is not necessarily the first
6548 	 * entry in the global dev_base list of net devices.  In fact,
6549 	 * it is likely to be the very last entry on that list.
6550 	 * So this causes the notifier registry below to try and
6551 	 * give link-local addresses to all devices besides loopback_dev
6552 	 * first, then loopback_dev, which cases all the non-loopback_dev
6553 	 * devices to fail to get a link-local address.
6554 	 *
6555 	 * So, as a temporary fix, allocate the ipv6 structure for
6556 	 * loopback_dev first by hand.
6557 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6558 	 * device and it being up should be removed.
6559 	 */
6560 	rtnl_lock();
6561 	idev = ipv6_add_dev(init_net.loopback_dev);
6562 	rtnl_unlock();
6563 	if (IS_ERR(idev)) {
6564 		err = PTR_ERR(idev);
6565 		goto errlo;
6566 	}
6567 
6568 	ip6_route_init_special_entries();
6569 
6570 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6571 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6572 
6573 	register_netdevice_notifier(&ipv6_dev_notf);
6574 
6575 	addrconf_verify();
6576 
6577 	rtnl_af_register(&inet6_ops);
6578 
6579 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6580 			      0);
6581 	if (err < 0)
6582 		goto errout;
6583 
6584 	/* Only the first call to __rtnl_register can fail */
6585 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, 0);
6586 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, 0);
6587 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6588 			inet6_dump_ifaddr, 0);
6589 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6590 			inet6_dump_ifmcaddr, 0);
6591 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6592 			inet6_dump_ifacaddr, 0);
6593 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6594 			inet6_netconf_dump_devconf, 0);
6595 
6596 	ipv6_addr_label_rtnl_register();
6597 
6598 	return 0;
6599 errout:
6600 	rtnl_af_unregister(&inet6_ops);
6601 	unregister_netdevice_notifier(&ipv6_dev_notf);
6602 errlo:
6603 	destroy_workqueue(addrconf_wq);
6604 out_nowq:
6605 	unregister_pernet_subsys(&addrconf_ops);
6606 out_addrlabel:
6607 	ipv6_addr_label_cleanup();
6608 out:
6609 	return err;
6610 }
6611 
6612 void addrconf_cleanup(void)
6613 {
6614 	struct net_device *dev;
6615 	int i;
6616 
6617 	unregister_netdevice_notifier(&ipv6_dev_notf);
6618 	unregister_pernet_subsys(&addrconf_ops);
6619 	ipv6_addr_label_cleanup();
6620 
6621 	rtnl_lock();
6622 
6623 	__rtnl_af_unregister(&inet6_ops);
6624 
6625 	/* clean dev list */
6626 	for_each_netdev(&init_net, dev) {
6627 		if (__in6_dev_get(dev) == NULL)
6628 			continue;
6629 		addrconf_ifdown(dev, 1);
6630 	}
6631 	addrconf_ifdown(init_net.loopback_dev, 2);
6632 
6633 	/*
6634 	 *	Check hash table.
6635 	 */
6636 	spin_lock_bh(&addrconf_hash_lock);
6637 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6638 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6639 	spin_unlock_bh(&addrconf_hash_lock);
6640 	cancel_delayed_work(&addr_chk_work);
6641 	rtnl_unlock();
6642 
6643 	destroy_workqueue(addrconf_wq);
6644 }
6645