xref: /linux/net/ipv6/addrconf.c (revision 995231c820e3bd3633cb38bf4ea6f2541e1da331)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
102 #else
103 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 #define IPV6_MAX_STRLEN \
109 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
110 
111 static inline u32 cstamp_delta(unsigned long cstamp)
112 {
113 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
114 }
115 
116 static inline s32 rfc3315_s14_backoff_init(s32 irt)
117 {
118 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
119 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
120 	do_div(tmp, 1000000);
121 	return (s32)tmp;
122 }
123 
124 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
125 {
126 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
127 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
128 	do_div(tmp, 1000000);
129 	if ((s32)tmp > mrt) {
130 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
131 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
132 		do_div(tmp, 1000000);
133 	}
134 	return (s32)tmp;
135 }
136 
137 #ifdef CONFIG_SYSCTL
138 static int addrconf_sysctl_register(struct inet6_dev *idev);
139 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
140 #else
141 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
142 {
143 	return 0;
144 }
145 
146 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
147 {
148 }
149 #endif
150 
151 static void ipv6_regen_rndid(struct inet6_dev *idev);
152 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
153 
154 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
155 static int ipv6_count_addresses(const struct inet6_dev *idev);
156 static int ipv6_generate_stable_address(struct in6_addr *addr,
157 					u8 dad_count,
158 					const struct inet6_dev *idev);
159 
160 /*
161  *	Configured unicast address hash table
162  */
163 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
164 static DEFINE_SPINLOCK(addrconf_hash_lock);
165 
166 static void addrconf_verify(void);
167 static void addrconf_verify_rtnl(void);
168 static void addrconf_verify_work(struct work_struct *);
169 
170 static struct workqueue_struct *addrconf_wq;
171 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
172 
173 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
174 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
175 
176 static void addrconf_type_change(struct net_device *dev,
177 				 unsigned long event);
178 static int addrconf_ifdown(struct net_device *dev, int how);
179 
180 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
181 						  int plen,
182 						  const struct net_device *dev,
183 						  u32 flags, u32 noflags);
184 
185 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
186 static void addrconf_dad_work(struct work_struct *w);
187 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id);
188 static void addrconf_dad_run(struct inet6_dev *idev);
189 static void addrconf_rs_timer(unsigned long data);
190 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
191 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
192 
193 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
194 				struct prefix_info *pinfo);
195 
196 static struct ipv6_devconf ipv6_devconf __read_mostly = {
197 	.forwarding		= 0,
198 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
199 	.mtu6			= IPV6_MIN_MTU,
200 	.accept_ra		= 1,
201 	.accept_redirects	= 1,
202 	.autoconf		= 1,
203 	.force_mld_version	= 0,
204 	.mldv1_unsolicited_report_interval = 10 * HZ,
205 	.mldv2_unsolicited_report_interval = HZ,
206 	.dad_transmits		= 1,
207 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
208 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
209 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
210 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
211 	.use_tempaddr		= 0,
212 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
213 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
214 	.regen_max_retry	= REGEN_MAX_RETRY,
215 	.max_desync_factor	= MAX_DESYNC_FACTOR,
216 	.max_addresses		= IPV6_MAX_ADDRESSES,
217 	.accept_ra_defrtr	= 1,
218 	.accept_ra_from_local	= 0,
219 	.accept_ra_min_hop_limit= 1,
220 	.accept_ra_pinfo	= 1,
221 #ifdef CONFIG_IPV6_ROUTER_PREF
222 	.accept_ra_rtr_pref	= 1,
223 	.rtr_probe_interval	= 60 * HZ,
224 #ifdef CONFIG_IPV6_ROUTE_INFO
225 	.accept_ra_rt_info_min_plen = 0,
226 	.accept_ra_rt_info_max_plen = 0,
227 #endif
228 #endif
229 	.proxy_ndp		= 0,
230 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
231 	.disable_ipv6		= 0,
232 	.accept_dad		= 1,
233 	.suppress_frag_ndisc	= 1,
234 	.accept_ra_mtu		= 1,
235 	.stable_secret		= {
236 		.initialized = false,
237 	},
238 	.use_oif_addrs_only	= 0,
239 	.ignore_routes_with_linkdown = 0,
240 	.keep_addr_on_down	= 0,
241 	.seg6_enabled		= 0,
242 #ifdef CONFIG_IPV6_SEG6_HMAC
243 	.seg6_require_hmac	= 0,
244 #endif
245 	.enhanced_dad           = 1,
246 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
247 	.disable_policy		= 0,
248 };
249 
250 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
251 	.forwarding		= 0,
252 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
253 	.mtu6			= IPV6_MIN_MTU,
254 	.accept_ra		= 1,
255 	.accept_redirects	= 1,
256 	.autoconf		= 1,
257 	.force_mld_version	= 0,
258 	.mldv1_unsolicited_report_interval = 10 * HZ,
259 	.mldv2_unsolicited_report_interval = HZ,
260 	.dad_transmits		= 1,
261 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
262 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
263 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
264 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
265 	.use_tempaddr		= 0,
266 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
267 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
268 	.regen_max_retry	= REGEN_MAX_RETRY,
269 	.max_desync_factor	= MAX_DESYNC_FACTOR,
270 	.max_addresses		= IPV6_MAX_ADDRESSES,
271 	.accept_ra_defrtr	= 1,
272 	.accept_ra_from_local	= 0,
273 	.accept_ra_min_hop_limit= 1,
274 	.accept_ra_pinfo	= 1,
275 #ifdef CONFIG_IPV6_ROUTER_PREF
276 	.accept_ra_rtr_pref	= 1,
277 	.rtr_probe_interval	= 60 * HZ,
278 #ifdef CONFIG_IPV6_ROUTE_INFO
279 	.accept_ra_rt_info_min_plen = 0,
280 	.accept_ra_rt_info_max_plen = 0,
281 #endif
282 #endif
283 	.proxy_ndp		= 0,
284 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
285 	.disable_ipv6		= 0,
286 	.accept_dad		= 1,
287 	.suppress_frag_ndisc	= 1,
288 	.accept_ra_mtu		= 1,
289 	.stable_secret		= {
290 		.initialized = false,
291 	},
292 	.use_oif_addrs_only	= 0,
293 	.ignore_routes_with_linkdown = 0,
294 	.keep_addr_on_down	= 0,
295 	.seg6_enabled		= 0,
296 #ifdef CONFIG_IPV6_SEG6_HMAC
297 	.seg6_require_hmac	= 0,
298 #endif
299 	.enhanced_dad           = 1,
300 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
301 	.disable_policy		= 0,
302 };
303 
304 /* Check if link is ready: is it up and is a valid qdisc available */
305 static inline bool addrconf_link_ready(const struct net_device *dev)
306 {
307 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
308 }
309 
310 static void addrconf_del_rs_timer(struct inet6_dev *idev)
311 {
312 	if (del_timer(&idev->rs_timer))
313 		__in6_dev_put(idev);
314 }
315 
316 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
317 {
318 	if (cancel_delayed_work(&ifp->dad_work))
319 		__in6_ifa_put(ifp);
320 }
321 
322 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
323 				  unsigned long when)
324 {
325 	if (!timer_pending(&idev->rs_timer))
326 		in6_dev_hold(idev);
327 	mod_timer(&idev->rs_timer, jiffies + when);
328 }
329 
330 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
331 				   unsigned long delay)
332 {
333 	in6_ifa_hold(ifp);
334 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
335 		in6_ifa_put(ifp);
336 }
337 
338 static int snmp6_alloc_dev(struct inet6_dev *idev)
339 {
340 	int i;
341 
342 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
343 	if (!idev->stats.ipv6)
344 		goto err_ip;
345 
346 	for_each_possible_cpu(i) {
347 		struct ipstats_mib *addrconf_stats;
348 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
349 		u64_stats_init(&addrconf_stats->syncp);
350 	}
351 
352 
353 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
354 					GFP_KERNEL);
355 	if (!idev->stats.icmpv6dev)
356 		goto err_icmp;
357 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
358 					   GFP_KERNEL);
359 	if (!idev->stats.icmpv6msgdev)
360 		goto err_icmpmsg;
361 
362 	return 0;
363 
364 err_icmpmsg:
365 	kfree(idev->stats.icmpv6dev);
366 err_icmp:
367 	free_percpu(idev->stats.ipv6);
368 err_ip:
369 	return -ENOMEM;
370 }
371 
372 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
373 {
374 	struct inet6_dev *ndev;
375 	int err = -ENOMEM;
376 
377 	ASSERT_RTNL();
378 
379 	if (dev->mtu < IPV6_MIN_MTU)
380 		return ERR_PTR(-EINVAL);
381 
382 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
383 	if (!ndev)
384 		return ERR_PTR(err);
385 
386 	rwlock_init(&ndev->lock);
387 	ndev->dev = dev;
388 	INIT_LIST_HEAD(&ndev->addr_list);
389 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
390 		    (unsigned long)ndev);
391 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
392 
393 	if (ndev->cnf.stable_secret.initialized)
394 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
395 	else
396 		ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
397 
398 	ndev->cnf.mtu6 = dev->mtu;
399 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
400 	if (!ndev->nd_parms) {
401 		kfree(ndev);
402 		return ERR_PTR(err);
403 	}
404 	if (ndev->cnf.forwarding)
405 		dev_disable_lro(dev);
406 	/* We refer to the device */
407 	dev_hold(dev);
408 
409 	if (snmp6_alloc_dev(ndev) < 0) {
410 		ADBG(KERN_WARNING
411 			"%s: cannot allocate memory for statistics; dev=%s.\n",
412 			__func__, dev->name);
413 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
414 		dev_put(dev);
415 		kfree(ndev);
416 		return ERR_PTR(err);
417 	}
418 
419 	if (snmp6_register_dev(ndev) < 0) {
420 		ADBG(KERN_WARNING
421 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
422 			__func__, dev->name);
423 		goto err_release;
424 	}
425 
426 	/* One reference from device. */
427 	refcount_set(&ndev->refcnt, 1);
428 
429 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
430 		ndev->cnf.accept_dad = -1;
431 
432 #if IS_ENABLED(CONFIG_IPV6_SIT)
433 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
434 		pr_info("%s: Disabled Multicast RS\n", dev->name);
435 		ndev->cnf.rtr_solicits = 0;
436 	}
437 #endif
438 
439 	INIT_LIST_HEAD(&ndev->tempaddr_list);
440 	ndev->desync_factor = U32_MAX;
441 	if ((dev->flags&IFF_LOOPBACK) ||
442 	    dev->type == ARPHRD_TUNNEL ||
443 	    dev->type == ARPHRD_TUNNEL6 ||
444 	    dev->type == ARPHRD_SIT ||
445 	    dev->type == ARPHRD_NONE) {
446 		ndev->cnf.use_tempaddr = -1;
447 	} else
448 		ipv6_regen_rndid(ndev);
449 
450 	ndev->token = in6addr_any;
451 
452 	if (netif_running(dev) && addrconf_link_ready(dev))
453 		ndev->if_flags |= IF_READY;
454 
455 	ipv6_mc_init_dev(ndev);
456 	ndev->tstamp = jiffies;
457 	err = addrconf_sysctl_register(ndev);
458 	if (err) {
459 		ipv6_mc_destroy_dev(ndev);
460 		snmp6_unregister_dev(ndev);
461 		goto err_release;
462 	}
463 	/* protected by rtnl_lock */
464 	rcu_assign_pointer(dev->ip6_ptr, ndev);
465 
466 	/* Join interface-local all-node multicast group */
467 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
468 
469 	/* Join all-node multicast group */
470 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
471 
472 	/* Join all-router multicast group if forwarding is set */
473 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
474 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
475 
476 	return ndev;
477 
478 err_release:
479 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
480 	ndev->dead = 1;
481 	in6_dev_finish_destroy(ndev);
482 	return ERR_PTR(err);
483 }
484 
485 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
486 {
487 	struct inet6_dev *idev;
488 
489 	ASSERT_RTNL();
490 
491 	idev = __in6_dev_get(dev);
492 	if (!idev) {
493 		idev = ipv6_add_dev(dev);
494 		if (IS_ERR(idev))
495 			return NULL;
496 	}
497 
498 	if (dev->flags&IFF_UP)
499 		ipv6_mc_up(idev);
500 	return idev;
501 }
502 
503 static int inet6_netconf_msgsize_devconf(int type)
504 {
505 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
506 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
507 	bool all = false;
508 
509 	if (type == NETCONFA_ALL)
510 		all = true;
511 
512 	if (all || type == NETCONFA_FORWARDING)
513 		size += nla_total_size(4);
514 #ifdef CONFIG_IPV6_MROUTE
515 	if (all || type == NETCONFA_MC_FORWARDING)
516 		size += nla_total_size(4);
517 #endif
518 	if (all || type == NETCONFA_PROXY_NEIGH)
519 		size += nla_total_size(4);
520 
521 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
522 		size += nla_total_size(4);
523 
524 	return size;
525 }
526 
527 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
528 				      struct ipv6_devconf *devconf, u32 portid,
529 				      u32 seq, int event, unsigned int flags,
530 				      int type)
531 {
532 	struct nlmsghdr  *nlh;
533 	struct netconfmsg *ncm;
534 	bool all = false;
535 
536 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
537 			flags);
538 	if (!nlh)
539 		return -EMSGSIZE;
540 
541 	if (type == NETCONFA_ALL)
542 		all = true;
543 
544 	ncm = nlmsg_data(nlh);
545 	ncm->ncm_family = AF_INET6;
546 
547 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
548 		goto nla_put_failure;
549 
550 	if (!devconf)
551 		goto out;
552 
553 	if ((all || type == NETCONFA_FORWARDING) &&
554 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
555 		goto nla_put_failure;
556 #ifdef CONFIG_IPV6_MROUTE
557 	if ((all || type == NETCONFA_MC_FORWARDING) &&
558 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
559 			devconf->mc_forwarding) < 0)
560 		goto nla_put_failure;
561 #endif
562 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
563 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
564 		goto nla_put_failure;
565 
566 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
567 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
568 			devconf->ignore_routes_with_linkdown) < 0)
569 		goto nla_put_failure;
570 
571 out:
572 	nlmsg_end(skb, nlh);
573 	return 0;
574 
575 nla_put_failure:
576 	nlmsg_cancel(skb, nlh);
577 	return -EMSGSIZE;
578 }
579 
580 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
581 				  int ifindex, struct ipv6_devconf *devconf)
582 {
583 	struct sk_buff *skb;
584 	int err = -ENOBUFS;
585 
586 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
587 	if (!skb)
588 		goto errout;
589 
590 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
591 					 event, 0, type);
592 	if (err < 0) {
593 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
594 		WARN_ON(err == -EMSGSIZE);
595 		kfree_skb(skb);
596 		goto errout;
597 	}
598 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
599 	return;
600 errout:
601 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
602 }
603 
604 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
605 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
606 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
607 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
608 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
609 };
610 
611 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
612 				     struct nlmsghdr *nlh,
613 				     struct netlink_ext_ack *extack)
614 {
615 	struct net *net = sock_net(in_skb->sk);
616 	struct nlattr *tb[NETCONFA_MAX+1];
617 	struct inet6_dev *in6_dev = NULL;
618 	struct net_device *dev = NULL;
619 	struct netconfmsg *ncm;
620 	struct sk_buff *skb;
621 	struct ipv6_devconf *devconf;
622 	int ifindex;
623 	int err;
624 
625 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
626 			  devconf_ipv6_policy, extack);
627 	if (err < 0)
628 		return err;
629 
630 	if (!tb[NETCONFA_IFINDEX])
631 		return -EINVAL;
632 
633 	err = -EINVAL;
634 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
635 	switch (ifindex) {
636 	case NETCONFA_IFINDEX_ALL:
637 		devconf = net->ipv6.devconf_all;
638 		break;
639 	case NETCONFA_IFINDEX_DEFAULT:
640 		devconf = net->ipv6.devconf_dflt;
641 		break;
642 	default:
643 		dev = dev_get_by_index(net, ifindex);
644 		if (!dev)
645 			return -EINVAL;
646 		in6_dev = in6_dev_get(dev);
647 		if (!in6_dev)
648 			goto errout;
649 		devconf = &in6_dev->cnf;
650 		break;
651 	}
652 
653 	err = -ENOBUFS;
654 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
655 	if (!skb)
656 		goto errout;
657 
658 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
659 					 NETLINK_CB(in_skb).portid,
660 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
661 					 NETCONFA_ALL);
662 	if (err < 0) {
663 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
664 		WARN_ON(err == -EMSGSIZE);
665 		kfree_skb(skb);
666 		goto errout;
667 	}
668 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
669 errout:
670 	if (in6_dev)
671 		in6_dev_put(in6_dev);
672 	if (dev)
673 		dev_put(dev);
674 	return err;
675 }
676 
677 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
678 				      struct netlink_callback *cb)
679 {
680 	struct net *net = sock_net(skb->sk);
681 	int h, s_h;
682 	int idx, s_idx;
683 	struct net_device *dev;
684 	struct inet6_dev *idev;
685 	struct hlist_head *head;
686 
687 	s_h = cb->args[0];
688 	s_idx = idx = cb->args[1];
689 
690 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
691 		idx = 0;
692 		head = &net->dev_index_head[h];
693 		rcu_read_lock();
694 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
695 			  net->dev_base_seq;
696 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
697 			if (idx < s_idx)
698 				goto cont;
699 			idev = __in6_dev_get(dev);
700 			if (!idev)
701 				goto cont;
702 
703 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
704 						       &idev->cnf,
705 						       NETLINK_CB(cb->skb).portid,
706 						       cb->nlh->nlmsg_seq,
707 						       RTM_NEWNETCONF,
708 						       NLM_F_MULTI,
709 						       NETCONFA_ALL) < 0) {
710 				rcu_read_unlock();
711 				goto done;
712 			}
713 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
714 cont:
715 			idx++;
716 		}
717 		rcu_read_unlock();
718 	}
719 	if (h == NETDEV_HASHENTRIES) {
720 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
721 					       net->ipv6.devconf_all,
722 					       NETLINK_CB(cb->skb).portid,
723 					       cb->nlh->nlmsg_seq,
724 					       RTM_NEWNETCONF, NLM_F_MULTI,
725 					       NETCONFA_ALL) < 0)
726 			goto done;
727 		else
728 			h++;
729 	}
730 	if (h == NETDEV_HASHENTRIES + 1) {
731 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
732 					       net->ipv6.devconf_dflt,
733 					       NETLINK_CB(cb->skb).portid,
734 					       cb->nlh->nlmsg_seq,
735 					       RTM_NEWNETCONF, NLM_F_MULTI,
736 					       NETCONFA_ALL) < 0)
737 			goto done;
738 		else
739 			h++;
740 	}
741 done:
742 	cb->args[0] = h;
743 	cb->args[1] = idx;
744 
745 	return skb->len;
746 }
747 
748 #ifdef CONFIG_SYSCTL
749 static void dev_forward_change(struct inet6_dev *idev)
750 {
751 	struct net_device *dev;
752 	struct inet6_ifaddr *ifa;
753 
754 	if (!idev)
755 		return;
756 	dev = idev->dev;
757 	if (idev->cnf.forwarding)
758 		dev_disable_lro(dev);
759 	if (dev->flags & IFF_MULTICAST) {
760 		if (idev->cnf.forwarding) {
761 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
762 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
763 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
764 		} else {
765 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
766 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
767 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
768 		}
769 	}
770 
771 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
772 		if (ifa->flags&IFA_F_TENTATIVE)
773 			continue;
774 		if (idev->cnf.forwarding)
775 			addrconf_join_anycast(ifa);
776 		else
777 			addrconf_leave_anycast(ifa);
778 	}
779 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
780 				     NETCONFA_FORWARDING,
781 				     dev->ifindex, &idev->cnf);
782 }
783 
784 
785 static void addrconf_forward_change(struct net *net, __s32 newf)
786 {
787 	struct net_device *dev;
788 	struct inet6_dev *idev;
789 
790 	for_each_netdev(net, dev) {
791 		idev = __in6_dev_get(dev);
792 		if (idev) {
793 			int changed = (!idev->cnf.forwarding) ^ (!newf);
794 			idev->cnf.forwarding = newf;
795 			if (changed)
796 				dev_forward_change(idev);
797 		}
798 	}
799 }
800 
801 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
802 {
803 	struct net *net;
804 	int old;
805 
806 	if (!rtnl_trylock())
807 		return restart_syscall();
808 
809 	net = (struct net *)table->extra2;
810 	old = *p;
811 	*p = newf;
812 
813 	if (p == &net->ipv6.devconf_dflt->forwarding) {
814 		if ((!newf) ^ (!old))
815 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
816 						     NETCONFA_FORWARDING,
817 						     NETCONFA_IFINDEX_DEFAULT,
818 						     net->ipv6.devconf_dflt);
819 		rtnl_unlock();
820 		return 0;
821 	}
822 
823 	if (p == &net->ipv6.devconf_all->forwarding) {
824 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
825 
826 		net->ipv6.devconf_dflt->forwarding = newf;
827 		if ((!newf) ^ (!old_dflt))
828 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
829 						     NETCONFA_FORWARDING,
830 						     NETCONFA_IFINDEX_DEFAULT,
831 						     net->ipv6.devconf_dflt);
832 
833 		addrconf_forward_change(net, newf);
834 		if ((!newf) ^ (!old))
835 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
836 						     NETCONFA_FORWARDING,
837 						     NETCONFA_IFINDEX_ALL,
838 						     net->ipv6.devconf_all);
839 	} else if ((!newf) ^ (!old))
840 		dev_forward_change((struct inet6_dev *)table->extra1);
841 	rtnl_unlock();
842 
843 	if (newf)
844 		rt6_purge_dflt_routers(net);
845 	return 1;
846 }
847 
848 static void addrconf_linkdown_change(struct net *net, __s32 newf)
849 {
850 	struct net_device *dev;
851 	struct inet6_dev *idev;
852 
853 	for_each_netdev(net, dev) {
854 		idev = __in6_dev_get(dev);
855 		if (idev) {
856 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
857 
858 			idev->cnf.ignore_routes_with_linkdown = newf;
859 			if (changed)
860 				inet6_netconf_notify_devconf(dev_net(dev),
861 							     RTM_NEWNETCONF,
862 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
863 							     dev->ifindex,
864 							     &idev->cnf);
865 		}
866 	}
867 }
868 
869 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
870 {
871 	struct net *net;
872 	int old;
873 
874 	if (!rtnl_trylock())
875 		return restart_syscall();
876 
877 	net = (struct net *)table->extra2;
878 	old = *p;
879 	*p = newf;
880 
881 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
882 		if ((!newf) ^ (!old))
883 			inet6_netconf_notify_devconf(net,
884 						     RTM_NEWNETCONF,
885 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
886 						     NETCONFA_IFINDEX_DEFAULT,
887 						     net->ipv6.devconf_dflt);
888 		rtnl_unlock();
889 		return 0;
890 	}
891 
892 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
893 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
894 		addrconf_linkdown_change(net, newf);
895 		if ((!newf) ^ (!old))
896 			inet6_netconf_notify_devconf(net,
897 						     RTM_NEWNETCONF,
898 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
899 						     NETCONFA_IFINDEX_ALL,
900 						     net->ipv6.devconf_all);
901 	}
902 	rtnl_unlock();
903 
904 	return 1;
905 }
906 
907 #endif
908 
909 /* Nobody refers to this ifaddr, destroy it */
910 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
911 {
912 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
913 
914 #ifdef NET_REFCNT_DEBUG
915 	pr_debug("%s\n", __func__);
916 #endif
917 
918 	in6_dev_put(ifp->idev);
919 
920 	if (cancel_delayed_work(&ifp->dad_work))
921 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
922 			  ifp);
923 
924 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
925 		pr_warn("Freeing alive inet6 address %p\n", ifp);
926 		return;
927 	}
928 	ip6_rt_put(ifp->rt);
929 
930 	kfree_rcu(ifp, rcu);
931 }
932 
933 static void
934 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
935 {
936 	struct list_head *p;
937 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
938 
939 	/*
940 	 * Each device address list is sorted in order of scope -
941 	 * global before linklocal.
942 	 */
943 	list_for_each(p, &idev->addr_list) {
944 		struct inet6_ifaddr *ifa
945 			= list_entry(p, struct inet6_ifaddr, if_list);
946 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
947 			break;
948 	}
949 
950 	list_add_tail_rcu(&ifp->if_list, p);
951 }
952 
953 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
954 {
955 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
956 
957 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
958 }
959 
960 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
961 			       struct net_device *dev, unsigned int hash)
962 {
963 	struct inet6_ifaddr *ifp;
964 
965 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
966 		if (!net_eq(dev_net(ifp->idev->dev), net))
967 			continue;
968 		if (ipv6_addr_equal(&ifp->addr, addr)) {
969 			if (!dev || ifp->idev->dev == dev)
970 				return true;
971 		}
972 	}
973 	return false;
974 }
975 
976 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
977 {
978 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
979 	int err = 0;
980 
981 	spin_lock(&addrconf_hash_lock);
982 
983 	/* Ignore adding duplicate addresses on an interface */
984 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
985 		ADBG("ipv6_add_addr: already assigned\n");
986 		err = -EEXIST;
987 	} else {
988 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
989 	}
990 
991 	spin_unlock(&addrconf_hash_lock);
992 
993 	return err;
994 }
995 
996 /* On success it returns ifp with increased reference count */
997 
998 static struct inet6_ifaddr *
999 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
1000 	      const struct in6_addr *peer_addr, int pfxlen,
1001 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft,
1002 	      bool can_block, struct netlink_ext_ack *extack)
1003 {
1004 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1005 	struct net *net = dev_net(idev->dev);
1006 	struct inet6_ifaddr *ifa = NULL;
1007 	struct rt6_info *rt = NULL;
1008 	int err = 0;
1009 	int addr_type = ipv6_addr_type(addr);
1010 
1011 	if (addr_type == IPV6_ADDR_ANY ||
1012 	    addr_type & IPV6_ADDR_MULTICAST ||
1013 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1014 	     addr_type & IPV6_ADDR_LOOPBACK))
1015 		return ERR_PTR(-EADDRNOTAVAIL);
1016 
1017 	if (idev->dead) {
1018 		err = -ENODEV;			/*XXX*/
1019 		goto out;
1020 	}
1021 
1022 	if (idev->cnf.disable_ipv6) {
1023 		err = -EACCES;
1024 		goto out;
1025 	}
1026 
1027 	/* validator notifier needs to be blocking;
1028 	 * do not call in atomic context
1029 	 */
1030 	if (can_block) {
1031 		struct in6_validator_info i6vi = {
1032 			.i6vi_addr = *addr,
1033 			.i6vi_dev = idev,
1034 			.extack = extack,
1035 		};
1036 
1037 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1038 		err = notifier_to_errno(err);
1039 		if (err < 0)
1040 			goto out;
1041 	}
1042 
1043 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1044 	if (!ifa) {
1045 		ADBG("ipv6_add_addr: malloc failed\n");
1046 		err = -ENOBUFS;
1047 		goto out;
1048 	}
1049 
1050 	rt = addrconf_dst_alloc(idev, addr, false);
1051 	if (IS_ERR(rt)) {
1052 		err = PTR_ERR(rt);
1053 		rt = NULL;
1054 		goto out;
1055 	}
1056 
1057 	if (net->ipv6.devconf_all->disable_policy ||
1058 	    idev->cnf.disable_policy)
1059 		rt->dst.flags |= DST_NOPOLICY;
1060 
1061 	neigh_parms_data_state_setall(idev->nd_parms);
1062 
1063 	ifa->addr = *addr;
1064 	if (peer_addr)
1065 		ifa->peer_addr = *peer_addr;
1066 
1067 	spin_lock_init(&ifa->lock);
1068 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1069 	INIT_HLIST_NODE(&ifa->addr_lst);
1070 	ifa->scope = scope;
1071 	ifa->prefix_len = pfxlen;
1072 	ifa->flags = flags;
1073 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1074 	if (!(flags & IFA_F_NODAD))
1075 		ifa->flags |= IFA_F_TENTATIVE;
1076 	ifa->valid_lft = valid_lft;
1077 	ifa->prefered_lft = prefered_lft;
1078 	ifa->cstamp = ifa->tstamp = jiffies;
1079 	ifa->tokenized = false;
1080 
1081 	ifa->rt = rt;
1082 
1083 	ifa->idev = idev;
1084 	in6_dev_hold(idev);
1085 
1086 	/* For caller */
1087 	refcount_set(&ifa->refcnt, 1);
1088 
1089 	rcu_read_lock_bh();
1090 
1091 	err = ipv6_add_addr_hash(idev->dev, ifa);
1092 	if (err < 0) {
1093 		rcu_read_unlock_bh();
1094 		goto out;
1095 	}
1096 
1097 	write_lock(&idev->lock);
1098 
1099 	/* Add to inet6_dev unicast addr list. */
1100 	ipv6_link_dev_addr(idev, ifa);
1101 
1102 	if (ifa->flags&IFA_F_TEMPORARY) {
1103 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1104 		in6_ifa_hold(ifa);
1105 	}
1106 
1107 	in6_ifa_hold(ifa);
1108 	write_unlock(&idev->lock);
1109 
1110 	rcu_read_unlock_bh();
1111 
1112 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1113 out:
1114 	if (unlikely(err < 0)) {
1115 		if (rt)
1116 			ip6_rt_put(rt);
1117 		if (ifa) {
1118 			if (ifa->idev)
1119 				in6_dev_put(ifa->idev);
1120 			kfree(ifa);
1121 		}
1122 		ifa = ERR_PTR(err);
1123 	}
1124 
1125 	return ifa;
1126 }
1127 
1128 enum cleanup_prefix_rt_t {
1129 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1130 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1131 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1132 };
1133 
1134 /*
1135  * Check, whether the prefix for ifp would still need a prefix route
1136  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1137  * constants.
1138  *
1139  * 1) we don't purge prefix if address was not permanent.
1140  *    prefix is managed by its own lifetime.
1141  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1142  * 3) if there are no addresses, delete prefix.
1143  * 4) if there are still other permanent address(es),
1144  *    corresponding prefix is still permanent.
1145  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1146  *    don't purge the prefix, assume user space is managing it.
1147  * 6) otherwise, update prefix lifetime to the
1148  *    longest valid lifetime among the corresponding
1149  *    addresses on the device.
1150  *    Note: subsequent RA will update lifetime.
1151  **/
1152 static enum cleanup_prefix_rt_t
1153 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1154 {
1155 	struct inet6_ifaddr *ifa;
1156 	struct inet6_dev *idev = ifp->idev;
1157 	unsigned long lifetime;
1158 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1159 
1160 	*expires = jiffies;
1161 
1162 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1163 		if (ifa == ifp)
1164 			continue;
1165 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1166 				       ifp->prefix_len))
1167 			continue;
1168 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1169 			return CLEANUP_PREFIX_RT_NOP;
1170 
1171 		action = CLEANUP_PREFIX_RT_EXPIRE;
1172 
1173 		spin_lock(&ifa->lock);
1174 
1175 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1176 		/*
1177 		 * Note: Because this address is
1178 		 * not permanent, lifetime <
1179 		 * LONG_MAX / HZ here.
1180 		 */
1181 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1182 			*expires = ifa->tstamp + lifetime * HZ;
1183 		spin_unlock(&ifa->lock);
1184 	}
1185 
1186 	return action;
1187 }
1188 
1189 static void
1190 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1191 {
1192 	struct rt6_info *rt;
1193 
1194 	rt = addrconf_get_prefix_route(&ifp->addr,
1195 				       ifp->prefix_len,
1196 				       ifp->idev->dev,
1197 				       0, RTF_GATEWAY | RTF_DEFAULT);
1198 	if (rt) {
1199 		if (del_rt)
1200 			ip6_del_rt(rt);
1201 		else {
1202 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1203 				rt6_set_expires(rt, expires);
1204 			ip6_rt_put(rt);
1205 		}
1206 	}
1207 }
1208 
1209 
1210 /* This function wants to get referenced ifp and releases it before return */
1211 
1212 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1213 {
1214 	int state;
1215 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1216 	unsigned long expires;
1217 
1218 	ASSERT_RTNL();
1219 
1220 	spin_lock_bh(&ifp->lock);
1221 	state = ifp->state;
1222 	ifp->state = INET6_IFADDR_STATE_DEAD;
1223 	spin_unlock_bh(&ifp->lock);
1224 
1225 	if (state == INET6_IFADDR_STATE_DEAD)
1226 		goto out;
1227 
1228 	spin_lock_bh(&addrconf_hash_lock);
1229 	hlist_del_init_rcu(&ifp->addr_lst);
1230 	spin_unlock_bh(&addrconf_hash_lock);
1231 
1232 	write_lock_bh(&ifp->idev->lock);
1233 
1234 	if (ifp->flags&IFA_F_TEMPORARY) {
1235 		list_del(&ifp->tmp_list);
1236 		if (ifp->ifpub) {
1237 			in6_ifa_put(ifp->ifpub);
1238 			ifp->ifpub = NULL;
1239 		}
1240 		__in6_ifa_put(ifp);
1241 	}
1242 
1243 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1244 		action = check_cleanup_prefix_route(ifp, &expires);
1245 
1246 	list_del_rcu(&ifp->if_list);
1247 	__in6_ifa_put(ifp);
1248 
1249 	write_unlock_bh(&ifp->idev->lock);
1250 
1251 	addrconf_del_dad_work(ifp);
1252 
1253 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1254 
1255 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1256 
1257 	if (action != CLEANUP_PREFIX_RT_NOP) {
1258 		cleanup_prefix_route(ifp, expires,
1259 			action == CLEANUP_PREFIX_RT_DEL);
1260 	}
1261 
1262 	/* clean up prefsrc entries */
1263 	rt6_remove_prefsrc(ifp);
1264 out:
1265 	in6_ifa_put(ifp);
1266 }
1267 
1268 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1269 {
1270 	struct inet6_dev *idev = ifp->idev;
1271 	struct in6_addr addr, *tmpaddr;
1272 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1273 	unsigned long regen_advance;
1274 	int tmp_plen;
1275 	int ret = 0;
1276 	u32 addr_flags;
1277 	unsigned long now = jiffies;
1278 	long max_desync_factor;
1279 	s32 cnf_temp_preferred_lft;
1280 
1281 	write_lock_bh(&idev->lock);
1282 	if (ift) {
1283 		spin_lock_bh(&ift->lock);
1284 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1285 		spin_unlock_bh(&ift->lock);
1286 		tmpaddr = &addr;
1287 	} else {
1288 		tmpaddr = NULL;
1289 	}
1290 retry:
1291 	in6_dev_hold(idev);
1292 	if (idev->cnf.use_tempaddr <= 0) {
1293 		write_unlock_bh(&idev->lock);
1294 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1295 		in6_dev_put(idev);
1296 		ret = -1;
1297 		goto out;
1298 	}
1299 	spin_lock_bh(&ifp->lock);
1300 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1301 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1302 		spin_unlock_bh(&ifp->lock);
1303 		write_unlock_bh(&idev->lock);
1304 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1305 			__func__);
1306 		in6_dev_put(idev);
1307 		ret = -1;
1308 		goto out;
1309 	}
1310 	in6_ifa_hold(ifp);
1311 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1312 	ipv6_try_regen_rndid(idev, tmpaddr);
1313 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1314 	age = (now - ifp->tstamp) / HZ;
1315 
1316 	regen_advance = idev->cnf.regen_max_retry *
1317 			idev->cnf.dad_transmits *
1318 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1319 
1320 	/* recalculate max_desync_factor each time and update
1321 	 * idev->desync_factor if it's larger
1322 	 */
1323 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1324 	max_desync_factor = min_t(__u32,
1325 				  idev->cnf.max_desync_factor,
1326 				  cnf_temp_preferred_lft - regen_advance);
1327 
1328 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1329 		if (max_desync_factor > 0) {
1330 			get_random_bytes(&idev->desync_factor,
1331 					 sizeof(idev->desync_factor));
1332 			idev->desync_factor %= max_desync_factor;
1333 		} else {
1334 			idev->desync_factor = 0;
1335 		}
1336 	}
1337 
1338 	tmp_valid_lft = min_t(__u32,
1339 			      ifp->valid_lft,
1340 			      idev->cnf.temp_valid_lft + age);
1341 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1342 			    idev->desync_factor;
1343 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1344 	tmp_plen = ifp->prefix_len;
1345 	tmp_tstamp = ifp->tstamp;
1346 	spin_unlock_bh(&ifp->lock);
1347 
1348 	write_unlock_bh(&idev->lock);
1349 
1350 	/* A temporary address is created only if this calculated Preferred
1351 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1352 	 * an implementation must not create a temporary address with a zero
1353 	 * Preferred Lifetime.
1354 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1355 	 * temporary addresses being generated.
1356 	 */
1357 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1358 	if (tmp_prefered_lft <= regen_advance + age) {
1359 		in6_ifa_put(ifp);
1360 		in6_dev_put(idev);
1361 		ret = -1;
1362 		goto out;
1363 	}
1364 
1365 	addr_flags = IFA_F_TEMPORARY;
1366 	/* set in addrconf_prefix_rcv() */
1367 	if (ifp->flags & IFA_F_OPTIMISTIC)
1368 		addr_flags |= IFA_F_OPTIMISTIC;
1369 
1370 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1371 			    ipv6_addr_scope(&addr), addr_flags,
1372 			    tmp_valid_lft, tmp_prefered_lft, true, NULL);
1373 	if (IS_ERR(ift)) {
1374 		in6_ifa_put(ifp);
1375 		in6_dev_put(idev);
1376 		pr_info("%s: retry temporary address regeneration\n", __func__);
1377 		tmpaddr = &addr;
1378 		write_lock_bh(&idev->lock);
1379 		goto retry;
1380 	}
1381 
1382 	spin_lock_bh(&ift->lock);
1383 	ift->ifpub = ifp;
1384 	ift->cstamp = now;
1385 	ift->tstamp = tmp_tstamp;
1386 	spin_unlock_bh(&ift->lock);
1387 
1388 	addrconf_dad_start(ift);
1389 	in6_ifa_put(ift);
1390 	in6_dev_put(idev);
1391 out:
1392 	return ret;
1393 }
1394 
1395 /*
1396  *	Choose an appropriate source address (RFC3484)
1397  */
1398 enum {
1399 	IPV6_SADDR_RULE_INIT = 0,
1400 	IPV6_SADDR_RULE_LOCAL,
1401 	IPV6_SADDR_RULE_SCOPE,
1402 	IPV6_SADDR_RULE_PREFERRED,
1403 #ifdef CONFIG_IPV6_MIP6
1404 	IPV6_SADDR_RULE_HOA,
1405 #endif
1406 	IPV6_SADDR_RULE_OIF,
1407 	IPV6_SADDR_RULE_LABEL,
1408 	IPV6_SADDR_RULE_PRIVACY,
1409 	IPV6_SADDR_RULE_ORCHID,
1410 	IPV6_SADDR_RULE_PREFIX,
1411 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1412 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1413 #endif
1414 	IPV6_SADDR_RULE_MAX
1415 };
1416 
1417 struct ipv6_saddr_score {
1418 	int			rule;
1419 	int			addr_type;
1420 	struct inet6_ifaddr	*ifa;
1421 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1422 	int			scopedist;
1423 	int			matchlen;
1424 };
1425 
1426 struct ipv6_saddr_dst {
1427 	const struct in6_addr *addr;
1428 	int ifindex;
1429 	int scope;
1430 	int label;
1431 	unsigned int prefs;
1432 };
1433 
1434 static inline int ipv6_saddr_preferred(int type)
1435 {
1436 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1437 		return 1;
1438 	return 0;
1439 }
1440 
1441 static bool ipv6_use_optimistic_addr(struct net *net,
1442 				     struct inet6_dev *idev)
1443 {
1444 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1445 	if (!idev)
1446 		return false;
1447 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1448 		return false;
1449 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1450 		return false;
1451 
1452 	return true;
1453 #else
1454 	return false;
1455 #endif
1456 }
1457 
1458 static int ipv6_get_saddr_eval(struct net *net,
1459 			       struct ipv6_saddr_score *score,
1460 			       struct ipv6_saddr_dst *dst,
1461 			       int i)
1462 {
1463 	int ret;
1464 
1465 	if (i <= score->rule) {
1466 		switch (i) {
1467 		case IPV6_SADDR_RULE_SCOPE:
1468 			ret = score->scopedist;
1469 			break;
1470 		case IPV6_SADDR_RULE_PREFIX:
1471 			ret = score->matchlen;
1472 			break;
1473 		default:
1474 			ret = !!test_bit(i, score->scorebits);
1475 		}
1476 		goto out;
1477 	}
1478 
1479 	switch (i) {
1480 	case IPV6_SADDR_RULE_INIT:
1481 		/* Rule 0: remember if hiscore is not ready yet */
1482 		ret = !!score->ifa;
1483 		break;
1484 	case IPV6_SADDR_RULE_LOCAL:
1485 		/* Rule 1: Prefer same address */
1486 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1487 		break;
1488 	case IPV6_SADDR_RULE_SCOPE:
1489 		/* Rule 2: Prefer appropriate scope
1490 		 *
1491 		 *      ret
1492 		 *       ^
1493 		 *    -1 |  d 15
1494 		 *    ---+--+-+---> scope
1495 		 *       |
1496 		 *       |             d is scope of the destination.
1497 		 *  B-d  |  \
1498 		 *       |   \      <- smaller scope is better if
1499 		 *  B-15 |    \        if scope is enough for destination.
1500 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1501 		 * d-C-1 | /
1502 		 *       |/         <- greater is better
1503 		 *   -C  /             if scope is not enough for destination.
1504 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1505 		 *
1506 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1507 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1508 		 * Assume B = 0 and we get C > 29.
1509 		 */
1510 		ret = __ipv6_addr_src_scope(score->addr_type);
1511 		if (ret >= dst->scope)
1512 			ret = -ret;
1513 		else
1514 			ret -= 128;	/* 30 is enough */
1515 		score->scopedist = ret;
1516 		break;
1517 	case IPV6_SADDR_RULE_PREFERRED:
1518 	    {
1519 		/* Rule 3: Avoid deprecated and optimistic addresses */
1520 		u8 avoid = IFA_F_DEPRECATED;
1521 
1522 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1523 			avoid |= IFA_F_OPTIMISTIC;
1524 		ret = ipv6_saddr_preferred(score->addr_type) ||
1525 		      !(score->ifa->flags & avoid);
1526 		break;
1527 	    }
1528 #ifdef CONFIG_IPV6_MIP6
1529 	case IPV6_SADDR_RULE_HOA:
1530 	    {
1531 		/* Rule 4: Prefer home address */
1532 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1533 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1534 		break;
1535 	    }
1536 #endif
1537 	case IPV6_SADDR_RULE_OIF:
1538 		/* Rule 5: Prefer outgoing interface */
1539 		ret = (!dst->ifindex ||
1540 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1541 		break;
1542 	case IPV6_SADDR_RULE_LABEL:
1543 		/* Rule 6: Prefer matching label */
1544 		ret = ipv6_addr_label(net,
1545 				      &score->ifa->addr, score->addr_type,
1546 				      score->ifa->idev->dev->ifindex) == dst->label;
1547 		break;
1548 	case IPV6_SADDR_RULE_PRIVACY:
1549 	    {
1550 		/* Rule 7: Prefer public address
1551 		 * Note: prefer temporary address if use_tempaddr >= 2
1552 		 */
1553 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1554 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1555 				score->ifa->idev->cnf.use_tempaddr >= 2;
1556 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1557 		break;
1558 	    }
1559 	case IPV6_SADDR_RULE_ORCHID:
1560 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1561 		 *	    non-ORCHID vs non-ORCHID
1562 		 */
1563 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1564 			ipv6_addr_orchid(dst->addr));
1565 		break;
1566 	case IPV6_SADDR_RULE_PREFIX:
1567 		/* Rule 8: Use longest matching prefix */
1568 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1569 		if (ret > score->ifa->prefix_len)
1570 			ret = score->ifa->prefix_len;
1571 		score->matchlen = ret;
1572 		break;
1573 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1574 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1575 		/* Optimistic addresses still have lower precedence than other
1576 		 * preferred addresses.
1577 		 */
1578 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1579 		break;
1580 #endif
1581 	default:
1582 		ret = 0;
1583 	}
1584 
1585 	if (ret)
1586 		__set_bit(i, score->scorebits);
1587 	score->rule = i;
1588 out:
1589 	return ret;
1590 }
1591 
1592 static int __ipv6_dev_get_saddr(struct net *net,
1593 				struct ipv6_saddr_dst *dst,
1594 				struct inet6_dev *idev,
1595 				struct ipv6_saddr_score *scores,
1596 				int hiscore_idx)
1597 {
1598 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1599 
1600 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1601 		int i;
1602 
1603 		/*
1604 		 * - Tentative Address (RFC2462 section 5.4)
1605 		 *  - A tentative address is not considered
1606 		 *    "assigned to an interface" in the traditional
1607 		 *    sense, unless it is also flagged as optimistic.
1608 		 * - Candidate Source Address (section 4)
1609 		 *  - In any case, anycast addresses, multicast
1610 		 *    addresses, and the unspecified address MUST
1611 		 *    NOT be included in a candidate set.
1612 		 */
1613 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1614 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1615 			continue;
1616 
1617 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1618 
1619 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1620 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1621 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1622 					    idev->dev->name);
1623 			continue;
1624 		}
1625 
1626 		score->rule = -1;
1627 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1628 
1629 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1630 			int minihiscore, miniscore;
1631 
1632 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1633 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1634 
1635 			if (minihiscore > miniscore) {
1636 				if (i == IPV6_SADDR_RULE_SCOPE &&
1637 				    score->scopedist > 0) {
1638 					/*
1639 					 * special case:
1640 					 * each remaining entry
1641 					 * has too small (not enough)
1642 					 * scope, because ifa entries
1643 					 * are sorted by their scope
1644 					 * values.
1645 					 */
1646 					goto out;
1647 				}
1648 				break;
1649 			} else if (minihiscore < miniscore) {
1650 				swap(hiscore, score);
1651 				hiscore_idx = 1 - hiscore_idx;
1652 
1653 				/* restore our iterator */
1654 				score->ifa = hiscore->ifa;
1655 
1656 				break;
1657 			}
1658 		}
1659 	}
1660 out:
1661 	return hiscore_idx;
1662 }
1663 
1664 static int ipv6_get_saddr_master(struct net *net,
1665 				 const struct net_device *dst_dev,
1666 				 const struct net_device *master,
1667 				 struct ipv6_saddr_dst *dst,
1668 				 struct ipv6_saddr_score *scores,
1669 				 int hiscore_idx)
1670 {
1671 	struct inet6_dev *idev;
1672 
1673 	idev = __in6_dev_get(dst_dev);
1674 	if (idev)
1675 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1676 						   scores, hiscore_idx);
1677 
1678 	idev = __in6_dev_get(master);
1679 	if (idev)
1680 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1681 						   scores, hiscore_idx);
1682 
1683 	return hiscore_idx;
1684 }
1685 
1686 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1687 		       const struct in6_addr *daddr, unsigned int prefs,
1688 		       struct in6_addr *saddr)
1689 {
1690 	struct ipv6_saddr_score scores[2], *hiscore;
1691 	struct ipv6_saddr_dst dst;
1692 	struct inet6_dev *idev;
1693 	struct net_device *dev;
1694 	int dst_type;
1695 	bool use_oif_addr = false;
1696 	int hiscore_idx = 0;
1697 	int ret = 0;
1698 
1699 	dst_type = __ipv6_addr_type(daddr);
1700 	dst.addr = daddr;
1701 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1702 	dst.scope = __ipv6_addr_src_scope(dst_type);
1703 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1704 	dst.prefs = prefs;
1705 
1706 	scores[hiscore_idx].rule = -1;
1707 	scores[hiscore_idx].ifa = NULL;
1708 
1709 	rcu_read_lock();
1710 
1711 	/* Candidate Source Address (section 4)
1712 	 *  - multicast and link-local destination address,
1713 	 *    the set of candidate source address MUST only
1714 	 *    include addresses assigned to interfaces
1715 	 *    belonging to the same link as the outgoing
1716 	 *    interface.
1717 	 * (- For site-local destination addresses, the
1718 	 *    set of candidate source addresses MUST only
1719 	 *    include addresses assigned to interfaces
1720 	 *    belonging to the same site as the outgoing
1721 	 *    interface.)
1722 	 *  - "It is RECOMMENDED that the candidate source addresses
1723 	 *    be the set of unicast addresses assigned to the
1724 	 *    interface that will be used to send to the destination
1725 	 *    (the 'outgoing' interface)." (RFC 6724)
1726 	 */
1727 	if (dst_dev) {
1728 		idev = __in6_dev_get(dst_dev);
1729 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1730 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1731 		    (idev && idev->cnf.use_oif_addrs_only)) {
1732 			use_oif_addr = true;
1733 		}
1734 	}
1735 
1736 	if (use_oif_addr) {
1737 		if (idev)
1738 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1739 	} else {
1740 		const struct net_device *master;
1741 		int master_idx = 0;
1742 
1743 		/* if dst_dev exists and is enslaved to an L3 device, then
1744 		 * prefer addresses from dst_dev and then the master over
1745 		 * any other enslaved devices in the L3 domain.
1746 		 */
1747 		master = l3mdev_master_dev_rcu(dst_dev);
1748 		if (master) {
1749 			master_idx = master->ifindex;
1750 
1751 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1752 							    master, &dst,
1753 							    scores, hiscore_idx);
1754 
1755 			if (scores[hiscore_idx].ifa)
1756 				goto out;
1757 		}
1758 
1759 		for_each_netdev_rcu(net, dev) {
1760 			/* only consider addresses on devices in the
1761 			 * same L3 domain
1762 			 */
1763 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1764 				continue;
1765 			idev = __in6_dev_get(dev);
1766 			if (!idev)
1767 				continue;
1768 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1769 		}
1770 	}
1771 
1772 out:
1773 	hiscore = &scores[hiscore_idx];
1774 	if (!hiscore->ifa)
1775 		ret = -EADDRNOTAVAIL;
1776 	else
1777 		*saddr = hiscore->ifa->addr;
1778 
1779 	rcu_read_unlock();
1780 	return ret;
1781 }
1782 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1783 
1784 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1785 		      u32 banned_flags)
1786 {
1787 	struct inet6_ifaddr *ifp;
1788 	int err = -EADDRNOTAVAIL;
1789 
1790 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1791 		if (ifp->scope > IFA_LINK)
1792 			break;
1793 		if (ifp->scope == IFA_LINK &&
1794 		    !(ifp->flags & banned_flags)) {
1795 			*addr = ifp->addr;
1796 			err = 0;
1797 			break;
1798 		}
1799 	}
1800 	return err;
1801 }
1802 
1803 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1804 		    u32 banned_flags)
1805 {
1806 	struct inet6_dev *idev;
1807 	int err = -EADDRNOTAVAIL;
1808 
1809 	rcu_read_lock();
1810 	idev = __in6_dev_get(dev);
1811 	if (idev) {
1812 		read_lock_bh(&idev->lock);
1813 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1814 		read_unlock_bh(&idev->lock);
1815 	}
1816 	rcu_read_unlock();
1817 	return err;
1818 }
1819 
1820 static int ipv6_count_addresses(const struct inet6_dev *idev)
1821 {
1822 	const struct inet6_ifaddr *ifp;
1823 	int cnt = 0;
1824 
1825 	rcu_read_lock();
1826 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1827 		cnt++;
1828 	rcu_read_unlock();
1829 	return cnt;
1830 }
1831 
1832 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1833 		  const struct net_device *dev, int strict)
1834 {
1835 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1836 }
1837 EXPORT_SYMBOL(ipv6_chk_addr);
1838 
1839 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1840 			    const struct net_device *dev, int strict,
1841 			    u32 banned_flags)
1842 {
1843 	unsigned int hash = inet6_addr_hash(net, addr);
1844 	struct inet6_ifaddr *ifp;
1845 	u32 ifp_flags;
1846 
1847 	rcu_read_lock();
1848 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1849 		if (!net_eq(dev_net(ifp->idev->dev), net))
1850 			continue;
1851 		/* Decouple optimistic from tentative for evaluation here.
1852 		 * Ban optimistic addresses explicitly, when required.
1853 		 */
1854 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1855 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1856 			    : ifp->flags;
1857 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1858 		    !(ifp_flags&banned_flags) &&
1859 		    (!dev || ifp->idev->dev == dev ||
1860 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1861 			rcu_read_unlock();
1862 			return 1;
1863 		}
1864 	}
1865 
1866 	rcu_read_unlock();
1867 	return 0;
1868 }
1869 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1870 
1871 
1872 /* Compares an address/prefix_len with addresses on device @dev.
1873  * If one is found it returns true.
1874  */
1875 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1876 	const unsigned int prefix_len, struct net_device *dev)
1877 {
1878 	const struct inet6_ifaddr *ifa;
1879 	const struct inet6_dev *idev;
1880 	bool ret = false;
1881 
1882 	rcu_read_lock();
1883 	idev = __in6_dev_get(dev);
1884 	if (idev) {
1885 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1886 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1887 			if (ret)
1888 				break;
1889 		}
1890 	}
1891 	rcu_read_unlock();
1892 
1893 	return ret;
1894 }
1895 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1896 
1897 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1898 {
1899 	const struct inet6_ifaddr *ifa;
1900 	const struct inet6_dev *idev;
1901 	int	onlink;
1902 
1903 	onlink = 0;
1904 	rcu_read_lock();
1905 	idev = __in6_dev_get(dev);
1906 	if (idev) {
1907 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1908 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1909 						   ifa->prefix_len);
1910 			if (onlink)
1911 				break;
1912 		}
1913 	}
1914 	rcu_read_unlock();
1915 	return onlink;
1916 }
1917 EXPORT_SYMBOL(ipv6_chk_prefix);
1918 
1919 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1920 				     struct net_device *dev, int strict)
1921 {
1922 	unsigned int hash = inet6_addr_hash(net, addr);
1923 	struct inet6_ifaddr *ifp, *result = NULL;
1924 
1925 	rcu_read_lock();
1926 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1927 		if (!net_eq(dev_net(ifp->idev->dev), net))
1928 			continue;
1929 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1930 			if (!dev || ifp->idev->dev == dev ||
1931 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1932 				result = ifp;
1933 				in6_ifa_hold(ifp);
1934 				break;
1935 			}
1936 		}
1937 	}
1938 	rcu_read_unlock();
1939 
1940 	return result;
1941 }
1942 
1943 /* Gets referenced address, destroys ifaddr */
1944 
1945 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1946 {
1947 	if (dad_failed)
1948 		ifp->flags |= IFA_F_DADFAILED;
1949 
1950 	if (ifp->flags&IFA_F_TEMPORARY) {
1951 		struct inet6_ifaddr *ifpub;
1952 		spin_lock_bh(&ifp->lock);
1953 		ifpub = ifp->ifpub;
1954 		if (ifpub) {
1955 			in6_ifa_hold(ifpub);
1956 			spin_unlock_bh(&ifp->lock);
1957 			ipv6_create_tempaddr(ifpub, ifp);
1958 			in6_ifa_put(ifpub);
1959 		} else {
1960 			spin_unlock_bh(&ifp->lock);
1961 		}
1962 		ipv6_del_addr(ifp);
1963 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1964 		spin_lock_bh(&ifp->lock);
1965 		addrconf_del_dad_work(ifp);
1966 		ifp->flags |= IFA_F_TENTATIVE;
1967 		spin_unlock_bh(&ifp->lock);
1968 		if (dad_failed)
1969 			ipv6_ifa_notify(0, ifp);
1970 		in6_ifa_put(ifp);
1971 	} else {
1972 		ipv6_del_addr(ifp);
1973 	}
1974 }
1975 
1976 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1977 {
1978 	int err = -ENOENT;
1979 
1980 	spin_lock_bh(&ifp->lock);
1981 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1982 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1983 		err = 0;
1984 	}
1985 	spin_unlock_bh(&ifp->lock);
1986 
1987 	return err;
1988 }
1989 
1990 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1991 {
1992 	struct inet6_dev *idev = ifp->idev;
1993 	struct net *net = dev_net(ifp->idev->dev);
1994 
1995 	if (addrconf_dad_end(ifp)) {
1996 		in6_ifa_put(ifp);
1997 		return;
1998 	}
1999 
2000 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
2001 			     ifp->idev->dev->name, &ifp->addr);
2002 
2003 	spin_lock_bh(&ifp->lock);
2004 
2005 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2006 		int scope = ifp->scope;
2007 		u32 flags = ifp->flags;
2008 		struct in6_addr new_addr;
2009 		struct inet6_ifaddr *ifp2;
2010 		u32 valid_lft, preferred_lft;
2011 		int pfxlen = ifp->prefix_len;
2012 		int retries = ifp->stable_privacy_retry + 1;
2013 
2014 		if (retries > net->ipv6.sysctl.idgen_retries) {
2015 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2016 					     ifp->idev->dev->name);
2017 			goto errdad;
2018 		}
2019 
2020 		new_addr = ifp->addr;
2021 		if (ipv6_generate_stable_address(&new_addr, retries,
2022 						 idev))
2023 			goto errdad;
2024 
2025 		valid_lft = ifp->valid_lft;
2026 		preferred_lft = ifp->prefered_lft;
2027 
2028 		spin_unlock_bh(&ifp->lock);
2029 
2030 		if (idev->cnf.max_addresses &&
2031 		    ipv6_count_addresses(idev) >=
2032 		    idev->cnf.max_addresses)
2033 			goto lock_errdad;
2034 
2035 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2036 				     ifp->idev->dev->name);
2037 
2038 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2039 				     scope, flags, valid_lft,
2040 				     preferred_lft, false, NULL);
2041 		if (IS_ERR(ifp2))
2042 			goto lock_errdad;
2043 
2044 		spin_lock_bh(&ifp2->lock);
2045 		ifp2->stable_privacy_retry = retries;
2046 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2047 		spin_unlock_bh(&ifp2->lock);
2048 
2049 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2050 		in6_ifa_put(ifp2);
2051 lock_errdad:
2052 		spin_lock_bh(&ifp->lock);
2053 	}
2054 
2055 errdad:
2056 	/* transition from _POSTDAD to _ERRDAD */
2057 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2058 	spin_unlock_bh(&ifp->lock);
2059 
2060 	addrconf_mod_dad_work(ifp, 0);
2061 	in6_ifa_put(ifp);
2062 }
2063 
2064 /* Join to solicited addr multicast group.
2065  * caller must hold RTNL */
2066 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2067 {
2068 	struct in6_addr maddr;
2069 
2070 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2071 		return;
2072 
2073 	addrconf_addr_solict_mult(addr, &maddr);
2074 	ipv6_dev_mc_inc(dev, &maddr);
2075 }
2076 
2077 /* caller must hold RTNL */
2078 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2079 {
2080 	struct in6_addr maddr;
2081 
2082 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2083 		return;
2084 
2085 	addrconf_addr_solict_mult(addr, &maddr);
2086 	__ipv6_dev_mc_dec(idev, &maddr);
2087 }
2088 
2089 /* caller must hold RTNL */
2090 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2091 {
2092 	struct in6_addr addr;
2093 
2094 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2095 		return;
2096 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2097 	if (ipv6_addr_any(&addr))
2098 		return;
2099 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2100 }
2101 
2102 /* caller must hold RTNL */
2103 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2104 {
2105 	struct in6_addr addr;
2106 
2107 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2108 		return;
2109 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2110 	if (ipv6_addr_any(&addr))
2111 		return;
2112 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2113 }
2114 
2115 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2116 {
2117 	switch (dev->addr_len) {
2118 	case ETH_ALEN:
2119 		memcpy(eui, dev->dev_addr, 3);
2120 		eui[3] = 0xFF;
2121 		eui[4] = 0xFE;
2122 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2123 		break;
2124 	case EUI64_ADDR_LEN:
2125 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2126 		eui[0] ^= 2;
2127 		break;
2128 	default:
2129 		return -1;
2130 	}
2131 
2132 	return 0;
2133 }
2134 
2135 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2136 {
2137 	union fwnet_hwaddr *ha;
2138 
2139 	if (dev->addr_len != FWNET_ALEN)
2140 		return -1;
2141 
2142 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2143 
2144 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2145 	eui[0] ^= 2;
2146 	return 0;
2147 }
2148 
2149 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2150 {
2151 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2152 	if (dev->addr_len != ARCNET_ALEN)
2153 		return -1;
2154 	memset(eui, 0, 7);
2155 	eui[7] = *(u8 *)dev->dev_addr;
2156 	return 0;
2157 }
2158 
2159 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2160 {
2161 	if (dev->addr_len != INFINIBAND_ALEN)
2162 		return -1;
2163 	memcpy(eui, dev->dev_addr + 12, 8);
2164 	eui[0] |= 2;
2165 	return 0;
2166 }
2167 
2168 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2169 {
2170 	if (addr == 0)
2171 		return -1;
2172 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2173 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2174 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2175 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2176 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2177 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2178 	eui[1] = 0;
2179 	eui[2] = 0x5E;
2180 	eui[3] = 0xFE;
2181 	memcpy(eui + 4, &addr, 4);
2182 	return 0;
2183 }
2184 
2185 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2186 {
2187 	if (dev->priv_flags & IFF_ISATAP)
2188 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2189 	return -1;
2190 }
2191 
2192 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2193 {
2194 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2195 }
2196 
2197 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2198 {
2199 	memcpy(eui, dev->perm_addr, 3);
2200 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2201 	eui[3] = 0xFF;
2202 	eui[4] = 0xFE;
2203 	eui[0] ^= 2;
2204 	return 0;
2205 }
2206 
2207 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2208 {
2209 	switch (dev->type) {
2210 	case ARPHRD_ETHER:
2211 	case ARPHRD_FDDI:
2212 		return addrconf_ifid_eui48(eui, dev);
2213 	case ARPHRD_ARCNET:
2214 		return addrconf_ifid_arcnet(eui, dev);
2215 	case ARPHRD_INFINIBAND:
2216 		return addrconf_ifid_infiniband(eui, dev);
2217 	case ARPHRD_SIT:
2218 		return addrconf_ifid_sit(eui, dev);
2219 	case ARPHRD_IPGRE:
2220 	case ARPHRD_TUNNEL:
2221 		return addrconf_ifid_gre(eui, dev);
2222 	case ARPHRD_6LOWPAN:
2223 		return addrconf_ifid_6lowpan(eui, dev);
2224 	case ARPHRD_IEEE1394:
2225 		return addrconf_ifid_ieee1394(eui, dev);
2226 	case ARPHRD_TUNNEL6:
2227 	case ARPHRD_IP6GRE:
2228 		return addrconf_ifid_ip6tnl(eui, dev);
2229 	}
2230 	return -1;
2231 }
2232 
2233 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2234 {
2235 	int err = -1;
2236 	struct inet6_ifaddr *ifp;
2237 
2238 	read_lock_bh(&idev->lock);
2239 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2240 		if (ifp->scope > IFA_LINK)
2241 			break;
2242 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2243 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2244 			err = 0;
2245 			break;
2246 		}
2247 	}
2248 	read_unlock_bh(&idev->lock);
2249 	return err;
2250 }
2251 
2252 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2253 static void ipv6_regen_rndid(struct inet6_dev *idev)
2254 {
2255 regen:
2256 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2257 	idev->rndid[0] &= ~0x02;
2258 
2259 	/*
2260 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2261 	 * check if generated address is not inappropriate
2262 	 *
2263 	 *  - Reserved subnet anycast (RFC 2526)
2264 	 *	11111101 11....11 1xxxxxxx
2265 	 *  - ISATAP (RFC4214) 6.1
2266 	 *	00-00-5E-FE-xx-xx-xx-xx
2267 	 *  - value 0
2268 	 *  - XXX: already assigned to an address on the device
2269 	 */
2270 	if (idev->rndid[0] == 0xfd &&
2271 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2272 	    (idev->rndid[7]&0x80))
2273 		goto regen;
2274 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2275 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2276 			goto regen;
2277 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2278 			goto regen;
2279 	}
2280 }
2281 
2282 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2283 {
2284 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2285 		ipv6_regen_rndid(idev);
2286 }
2287 
2288 /*
2289  *	Add prefix route.
2290  */
2291 
2292 static void
2293 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2294 		      unsigned long expires, u32 flags)
2295 {
2296 	struct fib6_config cfg = {
2297 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2298 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2299 		.fc_ifindex = dev->ifindex,
2300 		.fc_expires = expires,
2301 		.fc_dst_len = plen,
2302 		.fc_flags = RTF_UP | flags,
2303 		.fc_nlinfo.nl_net = dev_net(dev),
2304 		.fc_protocol = RTPROT_KERNEL,
2305 	};
2306 
2307 	cfg.fc_dst = *pfx;
2308 
2309 	/* Prevent useless cloning on PtP SIT.
2310 	   This thing is done here expecting that the whole
2311 	   class of non-broadcast devices need not cloning.
2312 	 */
2313 #if IS_ENABLED(CONFIG_IPV6_SIT)
2314 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2315 		cfg.fc_flags |= RTF_NONEXTHOP;
2316 #endif
2317 
2318 	ip6_route_add(&cfg, NULL);
2319 }
2320 
2321 
2322 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2323 						  int plen,
2324 						  const struct net_device *dev,
2325 						  u32 flags, u32 noflags)
2326 {
2327 	struct fib6_node *fn;
2328 	struct rt6_info *rt = NULL;
2329 	struct fib6_table *table;
2330 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2331 
2332 	table = fib6_get_table(dev_net(dev), tb_id);
2333 	if (!table)
2334 		return NULL;
2335 
2336 	rcu_read_lock();
2337 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2338 	if (!fn)
2339 		goto out;
2340 
2341 	for_each_fib6_node_rt_rcu(fn) {
2342 		if (rt->dst.dev->ifindex != dev->ifindex)
2343 			continue;
2344 		if ((rt->rt6i_flags & flags) != flags)
2345 			continue;
2346 		if ((rt->rt6i_flags & noflags) != 0)
2347 			continue;
2348 		if (!dst_hold_safe(&rt->dst))
2349 			rt = NULL;
2350 		break;
2351 	}
2352 out:
2353 	rcu_read_unlock();
2354 	return rt;
2355 }
2356 
2357 
2358 /* Create "default" multicast route to the interface */
2359 
2360 static void addrconf_add_mroute(struct net_device *dev)
2361 {
2362 	struct fib6_config cfg = {
2363 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2364 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2365 		.fc_ifindex = dev->ifindex,
2366 		.fc_dst_len = 8,
2367 		.fc_flags = RTF_UP,
2368 		.fc_nlinfo.nl_net = dev_net(dev),
2369 	};
2370 
2371 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2372 
2373 	ip6_route_add(&cfg, NULL);
2374 }
2375 
2376 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2377 {
2378 	struct inet6_dev *idev;
2379 
2380 	ASSERT_RTNL();
2381 
2382 	idev = ipv6_find_idev(dev);
2383 	if (!idev)
2384 		return ERR_PTR(-ENOBUFS);
2385 
2386 	if (idev->cnf.disable_ipv6)
2387 		return ERR_PTR(-EACCES);
2388 
2389 	/* Add default multicast route */
2390 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2391 		addrconf_add_mroute(dev);
2392 
2393 	return idev;
2394 }
2395 
2396 static void manage_tempaddrs(struct inet6_dev *idev,
2397 			     struct inet6_ifaddr *ifp,
2398 			     __u32 valid_lft, __u32 prefered_lft,
2399 			     bool create, unsigned long now)
2400 {
2401 	u32 flags;
2402 	struct inet6_ifaddr *ift;
2403 
2404 	read_lock_bh(&idev->lock);
2405 	/* update all temporary addresses in the list */
2406 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2407 		int age, max_valid, max_prefered;
2408 
2409 		if (ifp != ift->ifpub)
2410 			continue;
2411 
2412 		/* RFC 4941 section 3.3:
2413 		 * If a received option will extend the lifetime of a public
2414 		 * address, the lifetimes of temporary addresses should
2415 		 * be extended, subject to the overall constraint that no
2416 		 * temporary addresses should ever remain "valid" or "preferred"
2417 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2418 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2419 		 */
2420 		age = (now - ift->cstamp) / HZ;
2421 		max_valid = idev->cnf.temp_valid_lft - age;
2422 		if (max_valid < 0)
2423 			max_valid = 0;
2424 
2425 		max_prefered = idev->cnf.temp_prefered_lft -
2426 			       idev->desync_factor - age;
2427 		if (max_prefered < 0)
2428 			max_prefered = 0;
2429 
2430 		if (valid_lft > max_valid)
2431 			valid_lft = max_valid;
2432 
2433 		if (prefered_lft > max_prefered)
2434 			prefered_lft = max_prefered;
2435 
2436 		spin_lock(&ift->lock);
2437 		flags = ift->flags;
2438 		ift->valid_lft = valid_lft;
2439 		ift->prefered_lft = prefered_lft;
2440 		ift->tstamp = now;
2441 		if (prefered_lft > 0)
2442 			ift->flags &= ~IFA_F_DEPRECATED;
2443 
2444 		spin_unlock(&ift->lock);
2445 		if (!(flags&IFA_F_TENTATIVE))
2446 			ipv6_ifa_notify(0, ift);
2447 	}
2448 
2449 	if ((create || list_empty(&idev->tempaddr_list)) &&
2450 	    idev->cnf.use_tempaddr > 0) {
2451 		/* When a new public address is created as described
2452 		 * in [ADDRCONF], also create a new temporary address.
2453 		 * Also create a temporary address if it's enabled but
2454 		 * no temporary address currently exists.
2455 		 */
2456 		read_unlock_bh(&idev->lock);
2457 		ipv6_create_tempaddr(ifp, NULL);
2458 	} else {
2459 		read_unlock_bh(&idev->lock);
2460 	}
2461 }
2462 
2463 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2464 {
2465 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2466 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2467 }
2468 
2469 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2470 				 const struct prefix_info *pinfo,
2471 				 struct inet6_dev *in6_dev,
2472 				 const struct in6_addr *addr, int addr_type,
2473 				 u32 addr_flags, bool sllao, bool tokenized,
2474 				 __u32 valid_lft, u32 prefered_lft)
2475 {
2476 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2477 	int create = 0, update_lft = 0;
2478 
2479 	if (!ifp && valid_lft) {
2480 		int max_addresses = in6_dev->cnf.max_addresses;
2481 
2482 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2483 		if ((net->ipv6.devconf_all->optimistic_dad ||
2484 		     in6_dev->cnf.optimistic_dad) &&
2485 		    !net->ipv6.devconf_all->forwarding && sllao)
2486 			addr_flags |= IFA_F_OPTIMISTIC;
2487 #endif
2488 
2489 		/* Do not allow to create too much of autoconfigured
2490 		 * addresses; this would be too easy way to crash kernel.
2491 		 */
2492 		if (!max_addresses ||
2493 		    ipv6_count_addresses(in6_dev) < max_addresses)
2494 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2495 					    pinfo->prefix_len,
2496 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2497 					    addr_flags, valid_lft,
2498 					    prefered_lft, false, NULL);
2499 
2500 		if (IS_ERR_OR_NULL(ifp))
2501 			return -1;
2502 
2503 		update_lft = 0;
2504 		create = 1;
2505 		spin_lock_bh(&ifp->lock);
2506 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2507 		ifp->cstamp = jiffies;
2508 		ifp->tokenized = tokenized;
2509 		spin_unlock_bh(&ifp->lock);
2510 		addrconf_dad_start(ifp);
2511 	}
2512 
2513 	if (ifp) {
2514 		u32 flags;
2515 		unsigned long now;
2516 		u32 stored_lft;
2517 
2518 		/* update lifetime (RFC2462 5.5.3 e) */
2519 		spin_lock_bh(&ifp->lock);
2520 		now = jiffies;
2521 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2522 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2523 		else
2524 			stored_lft = 0;
2525 		if (!update_lft && !create && stored_lft) {
2526 			const u32 minimum_lft = min_t(u32,
2527 				stored_lft, MIN_VALID_LIFETIME);
2528 			valid_lft = max(valid_lft, minimum_lft);
2529 
2530 			/* RFC4862 Section 5.5.3e:
2531 			 * "Note that the preferred lifetime of the
2532 			 *  corresponding address is always reset to
2533 			 *  the Preferred Lifetime in the received
2534 			 *  Prefix Information option, regardless of
2535 			 *  whether the valid lifetime is also reset or
2536 			 *  ignored."
2537 			 *
2538 			 * So we should always update prefered_lft here.
2539 			 */
2540 			update_lft = 1;
2541 		}
2542 
2543 		if (update_lft) {
2544 			ifp->valid_lft = valid_lft;
2545 			ifp->prefered_lft = prefered_lft;
2546 			ifp->tstamp = now;
2547 			flags = ifp->flags;
2548 			ifp->flags &= ~IFA_F_DEPRECATED;
2549 			spin_unlock_bh(&ifp->lock);
2550 
2551 			if (!(flags&IFA_F_TENTATIVE))
2552 				ipv6_ifa_notify(0, ifp);
2553 		} else
2554 			spin_unlock_bh(&ifp->lock);
2555 
2556 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2557 				 create, now);
2558 
2559 		in6_ifa_put(ifp);
2560 		addrconf_verify();
2561 	}
2562 
2563 	return 0;
2564 }
2565 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2566 
2567 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2568 {
2569 	struct prefix_info *pinfo;
2570 	__u32 valid_lft;
2571 	__u32 prefered_lft;
2572 	int addr_type, err;
2573 	u32 addr_flags = 0;
2574 	struct inet6_dev *in6_dev;
2575 	struct net *net = dev_net(dev);
2576 
2577 	pinfo = (struct prefix_info *) opt;
2578 
2579 	if (len < sizeof(struct prefix_info)) {
2580 		ADBG("addrconf: prefix option too short\n");
2581 		return;
2582 	}
2583 
2584 	/*
2585 	 *	Validation checks ([ADDRCONF], page 19)
2586 	 */
2587 
2588 	addr_type = ipv6_addr_type(&pinfo->prefix);
2589 
2590 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2591 		return;
2592 
2593 	valid_lft = ntohl(pinfo->valid);
2594 	prefered_lft = ntohl(pinfo->prefered);
2595 
2596 	if (prefered_lft > valid_lft) {
2597 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2598 		return;
2599 	}
2600 
2601 	in6_dev = in6_dev_get(dev);
2602 
2603 	if (!in6_dev) {
2604 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2605 				    dev->name);
2606 		return;
2607 	}
2608 
2609 	/*
2610 	 *	Two things going on here:
2611 	 *	1) Add routes for on-link prefixes
2612 	 *	2) Configure prefixes with the auto flag set
2613 	 */
2614 
2615 	if (pinfo->onlink) {
2616 		struct rt6_info *rt;
2617 		unsigned long rt_expires;
2618 
2619 		/* Avoid arithmetic overflow. Really, we could
2620 		 * save rt_expires in seconds, likely valid_lft,
2621 		 * but it would require division in fib gc, that it
2622 		 * not good.
2623 		 */
2624 		if (HZ > USER_HZ)
2625 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2626 		else
2627 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2628 
2629 		if (addrconf_finite_timeout(rt_expires))
2630 			rt_expires *= HZ;
2631 
2632 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2633 					       pinfo->prefix_len,
2634 					       dev,
2635 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2636 					       RTF_GATEWAY | RTF_DEFAULT);
2637 
2638 		if (rt) {
2639 			/* Autoconf prefix route */
2640 			if (valid_lft == 0) {
2641 				ip6_del_rt(rt);
2642 				rt = NULL;
2643 			} else if (addrconf_finite_timeout(rt_expires)) {
2644 				/* not infinity */
2645 				rt6_set_expires(rt, jiffies + rt_expires);
2646 			} else {
2647 				rt6_clean_expires(rt);
2648 			}
2649 		} else if (valid_lft) {
2650 			clock_t expires = 0;
2651 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2652 			if (addrconf_finite_timeout(rt_expires)) {
2653 				/* not infinity */
2654 				flags |= RTF_EXPIRES;
2655 				expires = jiffies_to_clock_t(rt_expires);
2656 			}
2657 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2658 					      dev, expires, flags);
2659 		}
2660 		ip6_rt_put(rt);
2661 	}
2662 
2663 	/* Try to figure out our local address for this prefix */
2664 
2665 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2666 		struct in6_addr addr;
2667 		bool tokenized = false, dev_addr_generated = false;
2668 
2669 		if (pinfo->prefix_len == 64) {
2670 			memcpy(&addr, &pinfo->prefix, 8);
2671 
2672 			if (!ipv6_addr_any(&in6_dev->token)) {
2673 				read_lock_bh(&in6_dev->lock);
2674 				memcpy(addr.s6_addr + 8,
2675 				       in6_dev->token.s6_addr + 8, 8);
2676 				read_unlock_bh(&in6_dev->lock);
2677 				tokenized = true;
2678 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2679 				   !ipv6_generate_stable_address(&addr, 0,
2680 								 in6_dev)) {
2681 				addr_flags |= IFA_F_STABLE_PRIVACY;
2682 				goto ok;
2683 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2684 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2685 				goto put;
2686 			} else {
2687 				dev_addr_generated = true;
2688 			}
2689 			goto ok;
2690 		}
2691 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2692 				    pinfo->prefix_len);
2693 		goto put;
2694 
2695 ok:
2696 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2697 						   &addr, addr_type,
2698 						   addr_flags, sllao,
2699 						   tokenized, valid_lft,
2700 						   prefered_lft);
2701 		if (err)
2702 			goto put;
2703 
2704 		/* Ignore error case here because previous prefix add addr was
2705 		 * successful which will be notified.
2706 		 */
2707 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2708 					      addr_type, addr_flags, sllao,
2709 					      tokenized, valid_lft,
2710 					      prefered_lft,
2711 					      dev_addr_generated);
2712 	}
2713 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2714 put:
2715 	in6_dev_put(in6_dev);
2716 }
2717 
2718 /*
2719  *	Set destination address.
2720  *	Special case for SIT interfaces where we create a new "virtual"
2721  *	device.
2722  */
2723 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2724 {
2725 	struct in6_ifreq ireq;
2726 	struct net_device *dev;
2727 	int err = -EINVAL;
2728 
2729 	rtnl_lock();
2730 
2731 	err = -EFAULT;
2732 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2733 		goto err_exit;
2734 
2735 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2736 
2737 	err = -ENODEV;
2738 	if (!dev)
2739 		goto err_exit;
2740 
2741 #if IS_ENABLED(CONFIG_IPV6_SIT)
2742 	if (dev->type == ARPHRD_SIT) {
2743 		const struct net_device_ops *ops = dev->netdev_ops;
2744 		struct ifreq ifr;
2745 		struct ip_tunnel_parm p;
2746 
2747 		err = -EADDRNOTAVAIL;
2748 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2749 			goto err_exit;
2750 
2751 		memset(&p, 0, sizeof(p));
2752 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2753 		p.iph.saddr = 0;
2754 		p.iph.version = 4;
2755 		p.iph.ihl = 5;
2756 		p.iph.protocol = IPPROTO_IPV6;
2757 		p.iph.ttl = 64;
2758 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2759 
2760 		if (ops->ndo_do_ioctl) {
2761 			mm_segment_t oldfs = get_fs();
2762 
2763 			set_fs(KERNEL_DS);
2764 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2765 			set_fs(oldfs);
2766 		} else
2767 			err = -EOPNOTSUPP;
2768 
2769 		if (err == 0) {
2770 			err = -ENOBUFS;
2771 			dev = __dev_get_by_name(net, p.name);
2772 			if (!dev)
2773 				goto err_exit;
2774 			err = dev_open(dev);
2775 		}
2776 	}
2777 #endif
2778 
2779 err_exit:
2780 	rtnl_unlock();
2781 	return err;
2782 }
2783 
2784 static int ipv6_mc_config(struct sock *sk, bool join,
2785 			  const struct in6_addr *addr, int ifindex)
2786 {
2787 	int ret;
2788 
2789 	ASSERT_RTNL();
2790 
2791 	lock_sock(sk);
2792 	if (join)
2793 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2794 	else
2795 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2796 	release_sock(sk);
2797 
2798 	return ret;
2799 }
2800 
2801 /*
2802  *	Manual configuration of address on an interface
2803  */
2804 static int inet6_addr_add(struct net *net, int ifindex,
2805 			  const struct in6_addr *pfx,
2806 			  const struct in6_addr *peer_pfx,
2807 			  unsigned int plen, __u32 ifa_flags,
2808 			  __u32 prefered_lft, __u32 valid_lft,
2809 			  struct netlink_ext_ack *extack)
2810 {
2811 	struct inet6_ifaddr *ifp;
2812 	struct inet6_dev *idev;
2813 	struct net_device *dev;
2814 	unsigned long timeout;
2815 	clock_t expires;
2816 	int scope;
2817 	u32 flags;
2818 
2819 	ASSERT_RTNL();
2820 
2821 	if (plen > 128)
2822 		return -EINVAL;
2823 
2824 	/* check the lifetime */
2825 	if (!valid_lft || prefered_lft > valid_lft)
2826 		return -EINVAL;
2827 
2828 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2829 		return -EINVAL;
2830 
2831 	dev = __dev_get_by_index(net, ifindex);
2832 	if (!dev)
2833 		return -ENODEV;
2834 
2835 	idev = addrconf_add_dev(dev);
2836 	if (IS_ERR(idev))
2837 		return PTR_ERR(idev);
2838 
2839 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2840 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2841 					 true, pfx, ifindex);
2842 
2843 		if (ret < 0)
2844 			return ret;
2845 	}
2846 
2847 	scope = ipv6_addr_scope(pfx);
2848 
2849 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2850 	if (addrconf_finite_timeout(timeout)) {
2851 		expires = jiffies_to_clock_t(timeout * HZ);
2852 		valid_lft = timeout;
2853 		flags = RTF_EXPIRES;
2854 	} else {
2855 		expires = 0;
2856 		flags = 0;
2857 		ifa_flags |= IFA_F_PERMANENT;
2858 	}
2859 
2860 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2861 	if (addrconf_finite_timeout(timeout)) {
2862 		if (timeout == 0)
2863 			ifa_flags |= IFA_F_DEPRECATED;
2864 		prefered_lft = timeout;
2865 	}
2866 
2867 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2868 			    valid_lft, prefered_lft, true, extack);
2869 
2870 	if (!IS_ERR(ifp)) {
2871 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2872 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2873 					      expires, flags);
2874 		}
2875 
2876 		/*
2877 		 * Note that section 3.1 of RFC 4429 indicates
2878 		 * that the Optimistic flag should not be set for
2879 		 * manually configured addresses
2880 		 */
2881 		addrconf_dad_start(ifp);
2882 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2883 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2884 					 true, jiffies);
2885 		in6_ifa_put(ifp);
2886 		addrconf_verify_rtnl();
2887 		return 0;
2888 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2889 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2890 			       false, pfx, ifindex);
2891 	}
2892 
2893 	return PTR_ERR(ifp);
2894 }
2895 
2896 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2897 			  const struct in6_addr *pfx, unsigned int plen)
2898 {
2899 	struct inet6_ifaddr *ifp;
2900 	struct inet6_dev *idev;
2901 	struct net_device *dev;
2902 
2903 	if (plen > 128)
2904 		return -EINVAL;
2905 
2906 	dev = __dev_get_by_index(net, ifindex);
2907 	if (!dev)
2908 		return -ENODEV;
2909 
2910 	idev = __in6_dev_get(dev);
2911 	if (!idev)
2912 		return -ENXIO;
2913 
2914 	read_lock_bh(&idev->lock);
2915 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2916 		if (ifp->prefix_len == plen &&
2917 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2918 			in6_ifa_hold(ifp);
2919 			read_unlock_bh(&idev->lock);
2920 
2921 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2922 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2923 				manage_tempaddrs(idev, ifp, 0, 0, false,
2924 						 jiffies);
2925 			ipv6_del_addr(ifp);
2926 			addrconf_verify_rtnl();
2927 			if (ipv6_addr_is_multicast(pfx)) {
2928 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2929 					       false, pfx, dev->ifindex);
2930 			}
2931 			return 0;
2932 		}
2933 	}
2934 	read_unlock_bh(&idev->lock);
2935 	return -EADDRNOTAVAIL;
2936 }
2937 
2938 
2939 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2940 {
2941 	struct in6_ifreq ireq;
2942 	int err;
2943 
2944 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2945 		return -EPERM;
2946 
2947 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2948 		return -EFAULT;
2949 
2950 	rtnl_lock();
2951 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2952 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2953 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, NULL);
2954 	rtnl_unlock();
2955 	return err;
2956 }
2957 
2958 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2959 {
2960 	struct in6_ifreq ireq;
2961 	int err;
2962 
2963 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2964 		return -EPERM;
2965 
2966 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2967 		return -EFAULT;
2968 
2969 	rtnl_lock();
2970 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2971 			     ireq.ifr6_prefixlen);
2972 	rtnl_unlock();
2973 	return err;
2974 }
2975 
2976 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2977 		     int plen, int scope)
2978 {
2979 	struct inet6_ifaddr *ifp;
2980 
2981 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2982 			    scope, IFA_F_PERMANENT,
2983 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME,
2984 			    true, NULL);
2985 	if (!IS_ERR(ifp)) {
2986 		spin_lock_bh(&ifp->lock);
2987 		ifp->flags &= ~IFA_F_TENTATIVE;
2988 		spin_unlock_bh(&ifp->lock);
2989 		rt_genid_bump_ipv6(dev_net(idev->dev));
2990 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2991 		in6_ifa_put(ifp);
2992 	}
2993 }
2994 
2995 #if IS_ENABLED(CONFIG_IPV6_SIT)
2996 static void sit_add_v4_addrs(struct inet6_dev *idev)
2997 {
2998 	struct in6_addr addr;
2999 	struct net_device *dev;
3000 	struct net *net = dev_net(idev->dev);
3001 	int scope, plen;
3002 	u32 pflags = 0;
3003 
3004 	ASSERT_RTNL();
3005 
3006 	memset(&addr, 0, sizeof(struct in6_addr));
3007 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3008 
3009 	if (idev->dev->flags&IFF_POINTOPOINT) {
3010 		addr.s6_addr32[0] = htonl(0xfe800000);
3011 		scope = IFA_LINK;
3012 		plen = 64;
3013 	} else {
3014 		scope = IPV6_ADDR_COMPATv4;
3015 		plen = 96;
3016 		pflags |= RTF_NONEXTHOP;
3017 	}
3018 
3019 	if (addr.s6_addr32[3]) {
3020 		add_addr(idev, &addr, plen, scope);
3021 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
3022 		return;
3023 	}
3024 
3025 	for_each_netdev(net, dev) {
3026 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3027 		if (in_dev && (dev->flags & IFF_UP)) {
3028 			struct in_ifaddr *ifa;
3029 
3030 			int flag = scope;
3031 
3032 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3033 
3034 				addr.s6_addr32[3] = ifa->ifa_local;
3035 
3036 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3037 					continue;
3038 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3039 					if (idev->dev->flags&IFF_POINTOPOINT)
3040 						continue;
3041 					flag |= IFA_HOST;
3042 				}
3043 
3044 				add_addr(idev, &addr, plen, flag);
3045 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3046 						      pflags);
3047 			}
3048 		}
3049 	}
3050 }
3051 #endif
3052 
3053 static void init_loopback(struct net_device *dev)
3054 {
3055 	struct inet6_dev  *idev;
3056 
3057 	/* ::1 */
3058 
3059 	ASSERT_RTNL();
3060 
3061 	idev = ipv6_find_idev(dev);
3062 	if (!idev) {
3063 		pr_debug("%s: add_dev failed\n", __func__);
3064 		return;
3065 	}
3066 
3067 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3068 }
3069 
3070 void addrconf_add_linklocal(struct inet6_dev *idev,
3071 			    const struct in6_addr *addr, u32 flags)
3072 {
3073 	struct inet6_ifaddr *ifp;
3074 	u32 addr_flags = flags | IFA_F_PERMANENT;
3075 
3076 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3077 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3078 	     idev->cnf.optimistic_dad) &&
3079 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3080 		addr_flags |= IFA_F_OPTIMISTIC;
3081 #endif
3082 
3083 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3084 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, true, NULL);
3085 	if (!IS_ERR(ifp)) {
3086 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3087 		addrconf_dad_start(ifp);
3088 		in6_ifa_put(ifp);
3089 	}
3090 }
3091 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3092 
3093 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3094 {
3095 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3096 		return true;
3097 
3098 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3099 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3100 		return true;
3101 
3102 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3103 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3104 		return true;
3105 
3106 	return false;
3107 }
3108 
3109 static int ipv6_generate_stable_address(struct in6_addr *address,
3110 					u8 dad_count,
3111 					const struct inet6_dev *idev)
3112 {
3113 	static DEFINE_SPINLOCK(lock);
3114 	static __u32 digest[SHA_DIGEST_WORDS];
3115 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3116 
3117 	static union {
3118 		char __data[SHA_MESSAGE_BYTES];
3119 		struct {
3120 			struct in6_addr secret;
3121 			__be32 prefix[2];
3122 			unsigned char hwaddr[MAX_ADDR_LEN];
3123 			u8 dad_count;
3124 		} __packed;
3125 	} data;
3126 
3127 	struct in6_addr secret;
3128 	struct in6_addr temp;
3129 	struct net *net = dev_net(idev->dev);
3130 
3131 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3132 
3133 	if (idev->cnf.stable_secret.initialized)
3134 		secret = idev->cnf.stable_secret.secret;
3135 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3136 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3137 	else
3138 		return -1;
3139 
3140 retry:
3141 	spin_lock_bh(&lock);
3142 
3143 	sha_init(digest);
3144 	memset(&data, 0, sizeof(data));
3145 	memset(workspace, 0, sizeof(workspace));
3146 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3147 	data.prefix[0] = address->s6_addr32[0];
3148 	data.prefix[1] = address->s6_addr32[1];
3149 	data.secret = secret;
3150 	data.dad_count = dad_count;
3151 
3152 	sha_transform(digest, data.__data, workspace);
3153 
3154 	temp = *address;
3155 	temp.s6_addr32[2] = (__force __be32)digest[0];
3156 	temp.s6_addr32[3] = (__force __be32)digest[1];
3157 
3158 	spin_unlock_bh(&lock);
3159 
3160 	if (ipv6_reserved_interfaceid(temp)) {
3161 		dad_count++;
3162 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3163 			return -1;
3164 		goto retry;
3165 	}
3166 
3167 	*address = temp;
3168 	return 0;
3169 }
3170 
3171 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3172 {
3173 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3174 
3175 	if (s->initialized)
3176 		return;
3177 	s = &idev->cnf.stable_secret;
3178 	get_random_bytes(&s->secret, sizeof(s->secret));
3179 	s->initialized = true;
3180 }
3181 
3182 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3183 {
3184 	struct in6_addr addr;
3185 
3186 	/* no link local addresses on L3 master devices */
3187 	if (netif_is_l3_master(idev->dev))
3188 		return;
3189 
3190 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3191 
3192 	switch (idev->cnf.addr_gen_mode) {
3193 	case IN6_ADDR_GEN_MODE_RANDOM:
3194 		ipv6_gen_mode_random_init(idev);
3195 		/* fallthrough */
3196 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3197 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3198 			addrconf_add_linklocal(idev, &addr,
3199 					       IFA_F_STABLE_PRIVACY);
3200 		else if (prefix_route)
3201 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3202 		break;
3203 	case IN6_ADDR_GEN_MODE_EUI64:
3204 		/* addrconf_add_linklocal also adds a prefix_route and we
3205 		 * only need to care about prefix routes if ipv6_generate_eui64
3206 		 * couldn't generate one.
3207 		 */
3208 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3209 			addrconf_add_linklocal(idev, &addr, 0);
3210 		else if (prefix_route)
3211 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3212 		break;
3213 	case IN6_ADDR_GEN_MODE_NONE:
3214 	default:
3215 		/* will not add any link local address */
3216 		break;
3217 	}
3218 }
3219 
3220 static void addrconf_dev_config(struct net_device *dev)
3221 {
3222 	struct inet6_dev *idev;
3223 
3224 	ASSERT_RTNL();
3225 
3226 	if ((dev->type != ARPHRD_ETHER) &&
3227 	    (dev->type != ARPHRD_FDDI) &&
3228 	    (dev->type != ARPHRD_ARCNET) &&
3229 	    (dev->type != ARPHRD_INFINIBAND) &&
3230 	    (dev->type != ARPHRD_IEEE1394) &&
3231 	    (dev->type != ARPHRD_TUNNEL6) &&
3232 	    (dev->type != ARPHRD_6LOWPAN) &&
3233 	    (dev->type != ARPHRD_IP6GRE) &&
3234 	    (dev->type != ARPHRD_IPGRE) &&
3235 	    (dev->type != ARPHRD_TUNNEL) &&
3236 	    (dev->type != ARPHRD_NONE)) {
3237 		/* Alas, we support only Ethernet autoconfiguration. */
3238 		return;
3239 	}
3240 
3241 	idev = addrconf_add_dev(dev);
3242 	if (IS_ERR(idev))
3243 		return;
3244 
3245 	/* this device type has no EUI support */
3246 	if (dev->type == ARPHRD_NONE &&
3247 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3248 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3249 
3250 	addrconf_addr_gen(idev, false);
3251 }
3252 
3253 #if IS_ENABLED(CONFIG_IPV6_SIT)
3254 static void addrconf_sit_config(struct net_device *dev)
3255 {
3256 	struct inet6_dev *idev;
3257 
3258 	ASSERT_RTNL();
3259 
3260 	/*
3261 	 * Configure the tunnel with one of our IPv4
3262 	 * addresses... we should configure all of
3263 	 * our v4 addrs in the tunnel
3264 	 */
3265 
3266 	idev = ipv6_find_idev(dev);
3267 	if (!idev) {
3268 		pr_debug("%s: add_dev failed\n", __func__);
3269 		return;
3270 	}
3271 
3272 	if (dev->priv_flags & IFF_ISATAP) {
3273 		addrconf_addr_gen(idev, false);
3274 		return;
3275 	}
3276 
3277 	sit_add_v4_addrs(idev);
3278 
3279 	if (dev->flags&IFF_POINTOPOINT)
3280 		addrconf_add_mroute(dev);
3281 }
3282 #endif
3283 
3284 #if IS_ENABLED(CONFIG_NET_IPGRE)
3285 static void addrconf_gre_config(struct net_device *dev)
3286 {
3287 	struct inet6_dev *idev;
3288 
3289 	ASSERT_RTNL();
3290 
3291 	idev = ipv6_find_idev(dev);
3292 	if (!idev) {
3293 		pr_debug("%s: add_dev failed\n", __func__);
3294 		return;
3295 	}
3296 
3297 	addrconf_addr_gen(idev, true);
3298 	if (dev->flags & IFF_POINTOPOINT)
3299 		addrconf_add_mroute(dev);
3300 }
3301 #endif
3302 
3303 static int fixup_permanent_addr(struct inet6_dev *idev,
3304 				struct inet6_ifaddr *ifp)
3305 {
3306 	/* !rt6i_node means the host route was removed from the
3307 	 * FIB, for example, if 'lo' device is taken down. In that
3308 	 * case regenerate the host route.
3309 	 */
3310 	if (!ifp->rt || !ifp->rt->rt6i_node) {
3311 		struct rt6_info *rt, *prev;
3312 
3313 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3314 		if (IS_ERR(rt))
3315 			return PTR_ERR(rt);
3316 
3317 		/* ifp->rt can be accessed outside of rtnl */
3318 		spin_lock(&ifp->lock);
3319 		prev = ifp->rt;
3320 		ifp->rt = rt;
3321 		spin_unlock(&ifp->lock);
3322 
3323 		ip6_rt_put(prev);
3324 	}
3325 
3326 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3327 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3328 				      idev->dev, 0, 0);
3329 	}
3330 
3331 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3332 		addrconf_dad_start(ifp);
3333 
3334 	return 0;
3335 }
3336 
3337 static void addrconf_permanent_addr(struct net_device *dev)
3338 {
3339 	struct inet6_ifaddr *ifp, *tmp;
3340 	struct inet6_dev *idev;
3341 
3342 	idev = __in6_dev_get(dev);
3343 	if (!idev)
3344 		return;
3345 
3346 	write_lock_bh(&idev->lock);
3347 
3348 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3349 		if ((ifp->flags & IFA_F_PERMANENT) &&
3350 		    fixup_permanent_addr(idev, ifp) < 0) {
3351 			write_unlock_bh(&idev->lock);
3352 			ipv6_del_addr(ifp);
3353 			write_lock_bh(&idev->lock);
3354 
3355 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3356 					     idev->dev->name, &ifp->addr);
3357 		}
3358 	}
3359 
3360 	write_unlock_bh(&idev->lock);
3361 }
3362 
3363 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3364 			   void *ptr)
3365 {
3366 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3367 	struct netdev_notifier_changeupper_info *info;
3368 	struct inet6_dev *idev = __in6_dev_get(dev);
3369 	struct net *net = dev_net(dev);
3370 	int run_pending = 0;
3371 	int err;
3372 
3373 	switch (event) {
3374 	case NETDEV_REGISTER:
3375 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3376 			idev = ipv6_add_dev(dev);
3377 			if (IS_ERR(idev))
3378 				return notifier_from_errno(PTR_ERR(idev));
3379 		}
3380 		break;
3381 
3382 	case NETDEV_CHANGEMTU:
3383 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3384 		if (dev->mtu < IPV6_MIN_MTU) {
3385 			addrconf_ifdown(dev, dev != net->loopback_dev);
3386 			break;
3387 		}
3388 
3389 		if (idev) {
3390 			rt6_mtu_change(dev, dev->mtu);
3391 			idev->cnf.mtu6 = dev->mtu;
3392 			break;
3393 		}
3394 
3395 		/* allocate new idev */
3396 		idev = ipv6_add_dev(dev);
3397 		if (IS_ERR(idev))
3398 			break;
3399 
3400 		/* device is still not ready */
3401 		if (!(idev->if_flags & IF_READY))
3402 			break;
3403 
3404 		run_pending = 1;
3405 
3406 		/* fall through */
3407 
3408 	case NETDEV_UP:
3409 	case NETDEV_CHANGE:
3410 		if (dev->flags & IFF_SLAVE)
3411 			break;
3412 
3413 		if (idev && idev->cnf.disable_ipv6)
3414 			break;
3415 
3416 		if (event == NETDEV_UP) {
3417 			/* restore routes for permanent addresses */
3418 			addrconf_permanent_addr(dev);
3419 
3420 			if (!addrconf_link_ready(dev)) {
3421 				/* device is not ready yet. */
3422 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3423 					dev->name);
3424 				break;
3425 			}
3426 
3427 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3428 				idev = ipv6_add_dev(dev);
3429 
3430 			if (!IS_ERR_OR_NULL(idev)) {
3431 				idev->if_flags |= IF_READY;
3432 				run_pending = 1;
3433 			}
3434 		} else if (event == NETDEV_CHANGE) {
3435 			if (!addrconf_link_ready(dev)) {
3436 				/* device is still not ready. */
3437 				break;
3438 			}
3439 
3440 			if (idev) {
3441 				if (idev->if_flags & IF_READY) {
3442 					/* device is already configured -
3443 					 * but resend MLD reports, we might
3444 					 * have roamed and need to update
3445 					 * multicast snooping switches
3446 					 */
3447 					ipv6_mc_up(idev);
3448 					break;
3449 				}
3450 				idev->if_flags |= IF_READY;
3451 			}
3452 
3453 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3454 				dev->name);
3455 
3456 			run_pending = 1;
3457 		}
3458 
3459 		switch (dev->type) {
3460 #if IS_ENABLED(CONFIG_IPV6_SIT)
3461 		case ARPHRD_SIT:
3462 			addrconf_sit_config(dev);
3463 			break;
3464 #endif
3465 #if IS_ENABLED(CONFIG_NET_IPGRE)
3466 		case ARPHRD_IPGRE:
3467 			addrconf_gre_config(dev);
3468 			break;
3469 #endif
3470 		case ARPHRD_LOOPBACK:
3471 			init_loopback(dev);
3472 			break;
3473 
3474 		default:
3475 			addrconf_dev_config(dev);
3476 			break;
3477 		}
3478 
3479 		if (!IS_ERR_OR_NULL(idev)) {
3480 			if (run_pending)
3481 				addrconf_dad_run(idev);
3482 
3483 			/*
3484 			 * If the MTU changed during the interface down,
3485 			 * when the interface up, the changed MTU must be
3486 			 * reflected in the idev as well as routers.
3487 			 */
3488 			if (idev->cnf.mtu6 != dev->mtu &&
3489 			    dev->mtu >= IPV6_MIN_MTU) {
3490 				rt6_mtu_change(dev, dev->mtu);
3491 				idev->cnf.mtu6 = dev->mtu;
3492 			}
3493 			idev->tstamp = jiffies;
3494 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3495 
3496 			/*
3497 			 * If the changed mtu during down is lower than
3498 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3499 			 */
3500 			if (dev->mtu < IPV6_MIN_MTU)
3501 				addrconf_ifdown(dev, dev != net->loopback_dev);
3502 		}
3503 		break;
3504 
3505 	case NETDEV_DOWN:
3506 	case NETDEV_UNREGISTER:
3507 		/*
3508 		 *	Remove all addresses from this interface.
3509 		 */
3510 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3511 		break;
3512 
3513 	case NETDEV_CHANGENAME:
3514 		if (idev) {
3515 			snmp6_unregister_dev(idev);
3516 			addrconf_sysctl_unregister(idev);
3517 			err = addrconf_sysctl_register(idev);
3518 			if (err)
3519 				return notifier_from_errno(err);
3520 			err = snmp6_register_dev(idev);
3521 			if (err) {
3522 				addrconf_sysctl_unregister(idev);
3523 				return notifier_from_errno(err);
3524 			}
3525 		}
3526 		break;
3527 
3528 	case NETDEV_PRE_TYPE_CHANGE:
3529 	case NETDEV_POST_TYPE_CHANGE:
3530 		if (idev)
3531 			addrconf_type_change(dev, event);
3532 		break;
3533 
3534 	case NETDEV_CHANGEUPPER:
3535 		info = ptr;
3536 
3537 		/* flush all routes if dev is linked to or unlinked from
3538 		 * an L3 master device (e.g., VRF)
3539 		 */
3540 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3541 			addrconf_ifdown(dev, 0);
3542 	}
3543 
3544 	return NOTIFY_OK;
3545 }
3546 
3547 /*
3548  *	addrconf module should be notified of a device going up
3549  */
3550 static struct notifier_block ipv6_dev_notf = {
3551 	.notifier_call = addrconf_notify,
3552 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3553 };
3554 
3555 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3556 {
3557 	struct inet6_dev *idev;
3558 	ASSERT_RTNL();
3559 
3560 	idev = __in6_dev_get(dev);
3561 
3562 	if (event == NETDEV_POST_TYPE_CHANGE)
3563 		ipv6_mc_remap(idev);
3564 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3565 		ipv6_mc_unmap(idev);
3566 }
3567 
3568 static bool addr_is_local(const struct in6_addr *addr)
3569 {
3570 	return ipv6_addr_type(addr) &
3571 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3572 }
3573 
3574 static int addrconf_ifdown(struct net_device *dev, int how)
3575 {
3576 	struct net *net = dev_net(dev);
3577 	struct inet6_dev *idev;
3578 	struct inet6_ifaddr *ifa, *tmp;
3579 	int _keep_addr;
3580 	bool keep_addr;
3581 	int state, i;
3582 
3583 	ASSERT_RTNL();
3584 
3585 	rt6_ifdown(net, dev);
3586 	neigh_ifdown(&nd_tbl, dev);
3587 
3588 	idev = __in6_dev_get(dev);
3589 	if (!idev)
3590 		return -ENODEV;
3591 
3592 	/*
3593 	 * Step 1: remove reference to ipv6 device from parent device.
3594 	 *	   Do not dev_put!
3595 	 */
3596 	if (how) {
3597 		idev->dead = 1;
3598 
3599 		/* protected by rtnl_lock */
3600 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3601 
3602 		/* Step 1.5: remove snmp6 entry */
3603 		snmp6_unregister_dev(idev);
3604 
3605 	}
3606 
3607 	/* aggregate the system setting and interface setting */
3608 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3609 	if (!_keep_addr)
3610 		_keep_addr = idev->cnf.keep_addr_on_down;
3611 
3612 	/* combine the user config with event to determine if permanent
3613 	 * addresses are to be removed from address hash table
3614 	 */
3615 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3616 
3617 	/* Step 2: clear hash table */
3618 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3619 		struct hlist_head *h = &inet6_addr_lst[i];
3620 
3621 		spin_lock_bh(&addrconf_hash_lock);
3622 restart:
3623 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3624 			if (ifa->idev == idev) {
3625 				addrconf_del_dad_work(ifa);
3626 				/* combined flag + permanent flag decide if
3627 				 * address is retained on a down event
3628 				 */
3629 				if (!keep_addr ||
3630 				    !(ifa->flags & IFA_F_PERMANENT) ||
3631 				    addr_is_local(&ifa->addr)) {
3632 					hlist_del_init_rcu(&ifa->addr_lst);
3633 					goto restart;
3634 				}
3635 			}
3636 		}
3637 		spin_unlock_bh(&addrconf_hash_lock);
3638 	}
3639 
3640 	write_lock_bh(&idev->lock);
3641 
3642 	addrconf_del_rs_timer(idev);
3643 
3644 	/* Step 2: clear flags for stateless addrconf */
3645 	if (!how)
3646 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3647 
3648 	/* Step 3: clear tempaddr list */
3649 	while (!list_empty(&idev->tempaddr_list)) {
3650 		ifa = list_first_entry(&idev->tempaddr_list,
3651 				       struct inet6_ifaddr, tmp_list);
3652 		list_del(&ifa->tmp_list);
3653 		write_unlock_bh(&idev->lock);
3654 		spin_lock_bh(&ifa->lock);
3655 
3656 		if (ifa->ifpub) {
3657 			in6_ifa_put(ifa->ifpub);
3658 			ifa->ifpub = NULL;
3659 		}
3660 		spin_unlock_bh(&ifa->lock);
3661 		in6_ifa_put(ifa);
3662 		write_lock_bh(&idev->lock);
3663 	}
3664 
3665 	/* re-combine the user config with event to determine if permanent
3666 	 * addresses are to be removed from the interface list
3667 	 */
3668 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3669 
3670 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3671 		struct rt6_info *rt = NULL;
3672 		bool keep;
3673 
3674 		addrconf_del_dad_work(ifa);
3675 
3676 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3677 			!addr_is_local(&ifa->addr);
3678 
3679 		write_unlock_bh(&idev->lock);
3680 		spin_lock_bh(&ifa->lock);
3681 
3682 		if (keep) {
3683 			/* set state to skip the notifier below */
3684 			state = INET6_IFADDR_STATE_DEAD;
3685 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3686 			if (!(ifa->flags & IFA_F_NODAD))
3687 				ifa->flags |= IFA_F_TENTATIVE;
3688 
3689 			rt = ifa->rt;
3690 			ifa->rt = NULL;
3691 		} else {
3692 			state = ifa->state;
3693 			ifa->state = INET6_IFADDR_STATE_DEAD;
3694 		}
3695 
3696 		spin_unlock_bh(&ifa->lock);
3697 
3698 		if (rt)
3699 			ip6_del_rt(rt);
3700 
3701 		if (state != INET6_IFADDR_STATE_DEAD) {
3702 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3703 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3704 		} else {
3705 			if (idev->cnf.forwarding)
3706 				addrconf_leave_anycast(ifa);
3707 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3708 		}
3709 
3710 		write_lock_bh(&idev->lock);
3711 		if (!keep) {
3712 			list_del_rcu(&ifa->if_list);
3713 			in6_ifa_put(ifa);
3714 		}
3715 	}
3716 
3717 	write_unlock_bh(&idev->lock);
3718 
3719 	/* Step 5: Discard anycast and multicast list */
3720 	if (how) {
3721 		ipv6_ac_destroy_dev(idev);
3722 		ipv6_mc_destroy_dev(idev);
3723 	} else {
3724 		ipv6_mc_down(idev);
3725 	}
3726 
3727 	idev->tstamp = jiffies;
3728 
3729 	/* Last: Shot the device (if unregistered) */
3730 	if (how) {
3731 		addrconf_sysctl_unregister(idev);
3732 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3733 		neigh_ifdown(&nd_tbl, dev);
3734 		in6_dev_put(idev);
3735 	}
3736 	return 0;
3737 }
3738 
3739 static void addrconf_rs_timer(unsigned long data)
3740 {
3741 	struct inet6_dev *idev = (struct inet6_dev *)data;
3742 	struct net_device *dev = idev->dev;
3743 	struct in6_addr lladdr;
3744 
3745 	write_lock(&idev->lock);
3746 	if (idev->dead || !(idev->if_flags & IF_READY))
3747 		goto out;
3748 
3749 	if (!ipv6_accept_ra(idev))
3750 		goto out;
3751 
3752 	/* Announcement received after solicitation was sent */
3753 	if (idev->if_flags & IF_RA_RCVD)
3754 		goto out;
3755 
3756 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3757 		write_unlock(&idev->lock);
3758 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3759 			ndisc_send_rs(dev, &lladdr,
3760 				      &in6addr_linklocal_allrouters);
3761 		else
3762 			goto put;
3763 
3764 		write_lock(&idev->lock);
3765 		idev->rs_interval = rfc3315_s14_backoff_update(
3766 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3767 		/* The wait after the last probe can be shorter */
3768 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3769 					     idev->cnf.rtr_solicits) ?
3770 				      idev->cnf.rtr_solicit_delay :
3771 				      idev->rs_interval);
3772 	} else {
3773 		/*
3774 		 * Note: we do not support deprecated "all on-link"
3775 		 * assumption any longer.
3776 		 */
3777 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3778 	}
3779 
3780 out:
3781 	write_unlock(&idev->lock);
3782 put:
3783 	in6_dev_put(idev);
3784 }
3785 
3786 /*
3787  *	Duplicate Address Detection
3788  */
3789 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3790 {
3791 	unsigned long rand_num;
3792 	struct inet6_dev *idev = ifp->idev;
3793 	u64 nonce;
3794 
3795 	if (ifp->flags & IFA_F_OPTIMISTIC)
3796 		rand_num = 0;
3797 	else
3798 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3799 
3800 	nonce = 0;
3801 	if (idev->cnf.enhanced_dad ||
3802 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3803 		do
3804 			get_random_bytes(&nonce, 6);
3805 		while (nonce == 0);
3806 	}
3807 	ifp->dad_nonce = nonce;
3808 	ifp->dad_probes = idev->cnf.dad_transmits;
3809 	addrconf_mod_dad_work(ifp, rand_num);
3810 }
3811 
3812 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3813 {
3814 	struct inet6_dev *idev = ifp->idev;
3815 	struct net_device *dev = idev->dev;
3816 	bool bump_id, notify = false;
3817 
3818 	addrconf_join_solict(dev, &ifp->addr);
3819 
3820 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3821 
3822 	read_lock_bh(&idev->lock);
3823 	spin_lock(&ifp->lock);
3824 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3825 		goto out;
3826 
3827 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3828 	    (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 &&
3829 	     idev->cnf.accept_dad < 1) ||
3830 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3831 	    ifp->flags & IFA_F_NODAD) {
3832 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3833 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3834 		spin_unlock(&ifp->lock);
3835 		read_unlock_bh(&idev->lock);
3836 
3837 		addrconf_dad_completed(ifp, bump_id);
3838 		return;
3839 	}
3840 
3841 	if (!(idev->if_flags & IF_READY)) {
3842 		spin_unlock(&ifp->lock);
3843 		read_unlock_bh(&idev->lock);
3844 		/*
3845 		 * If the device is not ready:
3846 		 * - keep it tentative if it is a permanent address.
3847 		 * - otherwise, kill it.
3848 		 */
3849 		in6_ifa_hold(ifp);
3850 		addrconf_dad_stop(ifp, 0);
3851 		return;
3852 	}
3853 
3854 	/*
3855 	 * Optimistic nodes can start receiving
3856 	 * Frames right away
3857 	 */
3858 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3859 		ip6_ins_rt(ifp->rt);
3860 		if (ipv6_use_optimistic_addr(dev_net(dev), idev)) {
3861 			/* Because optimistic nodes can use this address,
3862 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3863 			 */
3864 			notify = true;
3865 		}
3866 	}
3867 
3868 	addrconf_dad_kick(ifp);
3869 out:
3870 	spin_unlock(&ifp->lock);
3871 	read_unlock_bh(&idev->lock);
3872 	if (notify)
3873 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3874 }
3875 
3876 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3877 {
3878 	bool begin_dad = false;
3879 
3880 	spin_lock_bh(&ifp->lock);
3881 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3882 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3883 		begin_dad = true;
3884 	}
3885 	spin_unlock_bh(&ifp->lock);
3886 
3887 	if (begin_dad)
3888 		addrconf_mod_dad_work(ifp, 0);
3889 }
3890 
3891 static void addrconf_dad_work(struct work_struct *w)
3892 {
3893 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3894 						struct inet6_ifaddr,
3895 						dad_work);
3896 	struct inet6_dev *idev = ifp->idev;
3897 	bool bump_id, disable_ipv6 = false;
3898 	struct in6_addr mcaddr;
3899 
3900 	enum {
3901 		DAD_PROCESS,
3902 		DAD_BEGIN,
3903 		DAD_ABORT,
3904 	} action = DAD_PROCESS;
3905 
3906 	rtnl_lock();
3907 
3908 	spin_lock_bh(&ifp->lock);
3909 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3910 		action = DAD_BEGIN;
3911 		ifp->state = INET6_IFADDR_STATE_DAD;
3912 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3913 		action = DAD_ABORT;
3914 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3915 
3916 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3917 		     idev->cnf.accept_dad > 1) &&
3918 		    !idev->cnf.disable_ipv6 &&
3919 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3920 			struct in6_addr addr;
3921 
3922 			addr.s6_addr32[0] = htonl(0xfe800000);
3923 			addr.s6_addr32[1] = 0;
3924 
3925 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3926 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3927 				/* DAD failed for link-local based on MAC */
3928 				idev->cnf.disable_ipv6 = 1;
3929 
3930 				pr_info("%s: IPv6 being disabled!\n",
3931 					ifp->idev->dev->name);
3932 				disable_ipv6 = true;
3933 			}
3934 		}
3935 	}
3936 	spin_unlock_bh(&ifp->lock);
3937 
3938 	if (action == DAD_BEGIN) {
3939 		addrconf_dad_begin(ifp);
3940 		goto out;
3941 	} else if (action == DAD_ABORT) {
3942 		in6_ifa_hold(ifp);
3943 		addrconf_dad_stop(ifp, 1);
3944 		if (disable_ipv6)
3945 			addrconf_ifdown(idev->dev, 0);
3946 		goto out;
3947 	}
3948 
3949 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3950 		goto out;
3951 
3952 	write_lock_bh(&idev->lock);
3953 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3954 		write_unlock_bh(&idev->lock);
3955 		goto out;
3956 	}
3957 
3958 	spin_lock(&ifp->lock);
3959 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3960 		spin_unlock(&ifp->lock);
3961 		write_unlock_bh(&idev->lock);
3962 		goto out;
3963 	}
3964 
3965 	if (ifp->dad_probes == 0) {
3966 		/*
3967 		 * DAD was successful
3968 		 */
3969 
3970 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3971 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3972 		spin_unlock(&ifp->lock);
3973 		write_unlock_bh(&idev->lock);
3974 
3975 		addrconf_dad_completed(ifp, bump_id);
3976 
3977 		goto out;
3978 	}
3979 
3980 	ifp->dad_probes--;
3981 	addrconf_mod_dad_work(ifp,
3982 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
3983 	spin_unlock(&ifp->lock);
3984 	write_unlock_bh(&idev->lock);
3985 
3986 	/* send a neighbour solicitation for our addr */
3987 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3988 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
3989 		      ifp->dad_nonce);
3990 out:
3991 	in6_ifa_put(ifp);
3992 	rtnl_unlock();
3993 }
3994 
3995 /* ifp->idev must be at least read locked */
3996 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
3997 {
3998 	struct inet6_ifaddr *ifpiter;
3999 	struct inet6_dev *idev = ifp->idev;
4000 
4001 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4002 		if (ifpiter->scope > IFA_LINK)
4003 			break;
4004 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4005 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4006 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4007 		    IFA_F_PERMANENT)
4008 			return false;
4009 	}
4010 	return true;
4011 }
4012 
4013 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
4014 {
4015 	struct net_device *dev = ifp->idev->dev;
4016 	struct in6_addr lladdr;
4017 	bool send_rs, send_mld;
4018 
4019 	addrconf_del_dad_work(ifp);
4020 
4021 	/*
4022 	 *	Configure the address for reception. Now it is valid.
4023 	 */
4024 
4025 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4026 
4027 	/* If added prefix is link local and we are prepared to process
4028 	   router advertisements, start sending router solicitations.
4029 	 */
4030 
4031 	read_lock_bh(&ifp->idev->lock);
4032 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4033 	send_rs = send_mld &&
4034 		  ipv6_accept_ra(ifp->idev) &&
4035 		  ifp->idev->cnf.rtr_solicits != 0 &&
4036 		  (dev->flags&IFF_LOOPBACK) == 0;
4037 	read_unlock_bh(&ifp->idev->lock);
4038 
4039 	/* While dad is in progress mld report's source address is in6_addrany.
4040 	 * Resend with proper ll now.
4041 	 */
4042 	if (send_mld)
4043 		ipv6_mc_dad_complete(ifp->idev);
4044 
4045 	if (send_rs) {
4046 		/*
4047 		 *	If a host as already performed a random delay
4048 		 *	[...] as part of DAD [...] there is no need
4049 		 *	to delay again before sending the first RS
4050 		 */
4051 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4052 			return;
4053 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4054 
4055 		write_lock_bh(&ifp->idev->lock);
4056 		spin_lock(&ifp->lock);
4057 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4058 			ifp->idev->cnf.rtr_solicit_interval);
4059 		ifp->idev->rs_probes = 1;
4060 		ifp->idev->if_flags |= IF_RS_SENT;
4061 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4062 		spin_unlock(&ifp->lock);
4063 		write_unlock_bh(&ifp->idev->lock);
4064 	}
4065 
4066 	if (bump_id)
4067 		rt_genid_bump_ipv6(dev_net(dev));
4068 
4069 	/* Make sure that a new temporary address will be created
4070 	 * before this temporary address becomes deprecated.
4071 	 */
4072 	if (ifp->flags & IFA_F_TEMPORARY)
4073 		addrconf_verify_rtnl();
4074 }
4075 
4076 static void addrconf_dad_run(struct inet6_dev *idev)
4077 {
4078 	struct inet6_ifaddr *ifp;
4079 
4080 	read_lock_bh(&idev->lock);
4081 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4082 		spin_lock(&ifp->lock);
4083 		if (ifp->flags & IFA_F_TENTATIVE &&
4084 		    ifp->state == INET6_IFADDR_STATE_DAD)
4085 			addrconf_dad_kick(ifp);
4086 		spin_unlock(&ifp->lock);
4087 	}
4088 	read_unlock_bh(&idev->lock);
4089 }
4090 
4091 #ifdef CONFIG_PROC_FS
4092 struct if6_iter_state {
4093 	struct seq_net_private p;
4094 	int bucket;
4095 	int offset;
4096 };
4097 
4098 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4099 {
4100 	struct if6_iter_state *state = seq->private;
4101 	struct net *net = seq_file_net(seq);
4102 	struct inet6_ifaddr *ifa = NULL;
4103 	int p = 0;
4104 
4105 	/* initial bucket if pos is 0 */
4106 	if (pos == 0) {
4107 		state->bucket = 0;
4108 		state->offset = 0;
4109 	}
4110 
4111 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4112 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4113 					 addr_lst) {
4114 			if (!net_eq(dev_net(ifa->idev->dev), net))
4115 				continue;
4116 			/* sync with offset */
4117 			if (p < state->offset) {
4118 				p++;
4119 				continue;
4120 			}
4121 			state->offset++;
4122 			return ifa;
4123 		}
4124 
4125 		/* prepare for next bucket */
4126 		state->offset = 0;
4127 		p = 0;
4128 	}
4129 	return NULL;
4130 }
4131 
4132 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4133 					 struct inet6_ifaddr *ifa)
4134 {
4135 	struct if6_iter_state *state = seq->private;
4136 	struct net *net = seq_file_net(seq);
4137 
4138 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4139 		if (!net_eq(dev_net(ifa->idev->dev), net))
4140 			continue;
4141 		state->offset++;
4142 		return ifa;
4143 	}
4144 
4145 	while (++state->bucket < IN6_ADDR_HSIZE) {
4146 		state->offset = 0;
4147 		hlist_for_each_entry_rcu(ifa,
4148 				     &inet6_addr_lst[state->bucket], addr_lst) {
4149 			if (!net_eq(dev_net(ifa->idev->dev), net))
4150 				continue;
4151 			state->offset++;
4152 			return ifa;
4153 		}
4154 	}
4155 
4156 	return NULL;
4157 }
4158 
4159 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4160 	__acquires(rcu)
4161 {
4162 	rcu_read_lock();
4163 	return if6_get_first(seq, *pos);
4164 }
4165 
4166 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4167 {
4168 	struct inet6_ifaddr *ifa;
4169 
4170 	ifa = if6_get_next(seq, v);
4171 	++*pos;
4172 	return ifa;
4173 }
4174 
4175 static void if6_seq_stop(struct seq_file *seq, void *v)
4176 	__releases(rcu)
4177 {
4178 	rcu_read_unlock();
4179 }
4180 
4181 static int if6_seq_show(struct seq_file *seq, void *v)
4182 {
4183 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4184 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4185 		   &ifp->addr,
4186 		   ifp->idev->dev->ifindex,
4187 		   ifp->prefix_len,
4188 		   ifp->scope,
4189 		   (u8) ifp->flags,
4190 		   ifp->idev->dev->name);
4191 	return 0;
4192 }
4193 
4194 static const struct seq_operations if6_seq_ops = {
4195 	.start	= if6_seq_start,
4196 	.next	= if6_seq_next,
4197 	.show	= if6_seq_show,
4198 	.stop	= if6_seq_stop,
4199 };
4200 
4201 static int if6_seq_open(struct inode *inode, struct file *file)
4202 {
4203 	return seq_open_net(inode, file, &if6_seq_ops,
4204 			    sizeof(struct if6_iter_state));
4205 }
4206 
4207 static const struct file_operations if6_fops = {
4208 	.owner		= THIS_MODULE,
4209 	.open		= if6_seq_open,
4210 	.read		= seq_read,
4211 	.llseek		= seq_lseek,
4212 	.release	= seq_release_net,
4213 };
4214 
4215 static int __net_init if6_proc_net_init(struct net *net)
4216 {
4217 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4218 		return -ENOMEM;
4219 	return 0;
4220 }
4221 
4222 static void __net_exit if6_proc_net_exit(struct net *net)
4223 {
4224 	remove_proc_entry("if_inet6", net->proc_net);
4225 }
4226 
4227 static struct pernet_operations if6_proc_net_ops = {
4228 	.init = if6_proc_net_init,
4229 	.exit = if6_proc_net_exit,
4230 };
4231 
4232 int __init if6_proc_init(void)
4233 {
4234 	return register_pernet_subsys(&if6_proc_net_ops);
4235 }
4236 
4237 void if6_proc_exit(void)
4238 {
4239 	unregister_pernet_subsys(&if6_proc_net_ops);
4240 }
4241 #endif	/* CONFIG_PROC_FS */
4242 
4243 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4244 /* Check if address is a home address configured on any interface. */
4245 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4246 {
4247 	unsigned int hash = inet6_addr_hash(net, addr);
4248 	struct inet6_ifaddr *ifp = NULL;
4249 	int ret = 0;
4250 
4251 	rcu_read_lock();
4252 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4253 		if (!net_eq(dev_net(ifp->idev->dev), net))
4254 			continue;
4255 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4256 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4257 			ret = 1;
4258 			break;
4259 		}
4260 	}
4261 	rcu_read_unlock();
4262 	return ret;
4263 }
4264 #endif
4265 
4266 /*
4267  *	Periodic address status verification
4268  */
4269 
4270 static void addrconf_verify_rtnl(void)
4271 {
4272 	unsigned long now, next, next_sec, next_sched;
4273 	struct inet6_ifaddr *ifp;
4274 	int i;
4275 
4276 	ASSERT_RTNL();
4277 
4278 	rcu_read_lock_bh();
4279 	now = jiffies;
4280 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4281 
4282 	cancel_delayed_work(&addr_chk_work);
4283 
4284 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4285 restart:
4286 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4287 			unsigned long age;
4288 
4289 			/* When setting preferred_lft to a value not zero or
4290 			 * infinity, while valid_lft is infinity
4291 			 * IFA_F_PERMANENT has a non-infinity life time.
4292 			 */
4293 			if ((ifp->flags & IFA_F_PERMANENT) &&
4294 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4295 				continue;
4296 
4297 			spin_lock(&ifp->lock);
4298 			/* We try to batch several events at once. */
4299 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4300 
4301 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4302 			    age >= ifp->valid_lft) {
4303 				spin_unlock(&ifp->lock);
4304 				in6_ifa_hold(ifp);
4305 				ipv6_del_addr(ifp);
4306 				goto restart;
4307 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4308 				spin_unlock(&ifp->lock);
4309 				continue;
4310 			} else if (age >= ifp->prefered_lft) {
4311 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4312 				int deprecate = 0;
4313 
4314 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4315 					deprecate = 1;
4316 					ifp->flags |= IFA_F_DEPRECATED;
4317 				}
4318 
4319 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4320 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4321 					next = ifp->tstamp + ifp->valid_lft * HZ;
4322 
4323 				spin_unlock(&ifp->lock);
4324 
4325 				if (deprecate) {
4326 					in6_ifa_hold(ifp);
4327 
4328 					ipv6_ifa_notify(0, ifp);
4329 					in6_ifa_put(ifp);
4330 					goto restart;
4331 				}
4332 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4333 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4334 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4335 					ifp->idev->cnf.dad_transmits *
4336 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4337 
4338 				if (age >= ifp->prefered_lft - regen_advance) {
4339 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4340 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4341 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4342 					if (!ifp->regen_count && ifpub) {
4343 						ifp->regen_count++;
4344 						in6_ifa_hold(ifp);
4345 						in6_ifa_hold(ifpub);
4346 						spin_unlock(&ifp->lock);
4347 
4348 						spin_lock(&ifpub->lock);
4349 						ifpub->regen_count = 0;
4350 						spin_unlock(&ifpub->lock);
4351 						ipv6_create_tempaddr(ifpub, ifp);
4352 						in6_ifa_put(ifpub);
4353 						in6_ifa_put(ifp);
4354 						goto restart;
4355 					}
4356 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4357 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4358 				spin_unlock(&ifp->lock);
4359 			} else {
4360 				/* ifp->prefered_lft <= ifp->valid_lft */
4361 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4362 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4363 				spin_unlock(&ifp->lock);
4364 			}
4365 		}
4366 	}
4367 
4368 	next_sec = round_jiffies_up(next);
4369 	next_sched = next;
4370 
4371 	/* If rounded timeout is accurate enough, accept it. */
4372 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4373 		next_sched = next_sec;
4374 
4375 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4376 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4377 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4378 
4379 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4380 	      now, next, next_sec, next_sched);
4381 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4382 	rcu_read_unlock_bh();
4383 }
4384 
4385 static void addrconf_verify_work(struct work_struct *w)
4386 {
4387 	rtnl_lock();
4388 	addrconf_verify_rtnl();
4389 	rtnl_unlock();
4390 }
4391 
4392 static void addrconf_verify(void)
4393 {
4394 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4395 }
4396 
4397 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4398 				     struct in6_addr **peer_pfx)
4399 {
4400 	struct in6_addr *pfx = NULL;
4401 
4402 	*peer_pfx = NULL;
4403 
4404 	if (addr)
4405 		pfx = nla_data(addr);
4406 
4407 	if (local) {
4408 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4409 			*peer_pfx = pfx;
4410 		pfx = nla_data(local);
4411 	}
4412 
4413 	return pfx;
4414 }
4415 
4416 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4417 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4418 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4419 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4420 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4421 };
4422 
4423 static int
4424 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4425 		  struct netlink_ext_ack *extack)
4426 {
4427 	struct net *net = sock_net(skb->sk);
4428 	struct ifaddrmsg *ifm;
4429 	struct nlattr *tb[IFA_MAX+1];
4430 	struct in6_addr *pfx, *peer_pfx;
4431 	u32 ifa_flags;
4432 	int err;
4433 
4434 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4435 			  extack);
4436 	if (err < 0)
4437 		return err;
4438 
4439 	ifm = nlmsg_data(nlh);
4440 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4441 	if (!pfx)
4442 		return -EINVAL;
4443 
4444 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4445 
4446 	/* We ignore other flags so far. */
4447 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4448 
4449 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4450 			      ifm->ifa_prefixlen);
4451 }
4452 
4453 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4454 			     u32 prefered_lft, u32 valid_lft)
4455 {
4456 	u32 flags;
4457 	clock_t expires;
4458 	unsigned long timeout;
4459 	bool was_managetempaddr;
4460 	bool had_prefixroute;
4461 
4462 	ASSERT_RTNL();
4463 
4464 	if (!valid_lft || (prefered_lft > valid_lft))
4465 		return -EINVAL;
4466 
4467 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4468 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4469 		return -EINVAL;
4470 
4471 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4472 	if (addrconf_finite_timeout(timeout)) {
4473 		expires = jiffies_to_clock_t(timeout * HZ);
4474 		valid_lft = timeout;
4475 		flags = RTF_EXPIRES;
4476 	} else {
4477 		expires = 0;
4478 		flags = 0;
4479 		ifa_flags |= IFA_F_PERMANENT;
4480 	}
4481 
4482 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4483 	if (addrconf_finite_timeout(timeout)) {
4484 		if (timeout == 0)
4485 			ifa_flags |= IFA_F_DEPRECATED;
4486 		prefered_lft = timeout;
4487 	}
4488 
4489 	spin_lock_bh(&ifp->lock);
4490 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4491 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4492 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4493 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4494 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4495 			IFA_F_NOPREFIXROUTE);
4496 	ifp->flags |= ifa_flags;
4497 	ifp->tstamp = jiffies;
4498 	ifp->valid_lft = valid_lft;
4499 	ifp->prefered_lft = prefered_lft;
4500 
4501 	spin_unlock_bh(&ifp->lock);
4502 	if (!(ifp->flags&IFA_F_TENTATIVE))
4503 		ipv6_ifa_notify(0, ifp);
4504 
4505 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4506 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4507 				      expires, flags);
4508 	} else if (had_prefixroute) {
4509 		enum cleanup_prefix_rt_t action;
4510 		unsigned long rt_expires;
4511 
4512 		write_lock_bh(&ifp->idev->lock);
4513 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4514 		write_unlock_bh(&ifp->idev->lock);
4515 
4516 		if (action != CLEANUP_PREFIX_RT_NOP) {
4517 			cleanup_prefix_route(ifp, rt_expires,
4518 				action == CLEANUP_PREFIX_RT_DEL);
4519 		}
4520 	}
4521 
4522 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4523 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4524 			valid_lft = prefered_lft = 0;
4525 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4526 				 !was_managetempaddr, jiffies);
4527 	}
4528 
4529 	addrconf_verify_rtnl();
4530 
4531 	return 0;
4532 }
4533 
4534 static int
4535 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4536 		  struct netlink_ext_ack *extack)
4537 {
4538 	struct net *net = sock_net(skb->sk);
4539 	struct ifaddrmsg *ifm;
4540 	struct nlattr *tb[IFA_MAX+1];
4541 	struct in6_addr *pfx, *peer_pfx;
4542 	struct inet6_ifaddr *ifa;
4543 	struct net_device *dev;
4544 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4545 	u32 ifa_flags;
4546 	int err;
4547 
4548 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4549 			  extack);
4550 	if (err < 0)
4551 		return err;
4552 
4553 	ifm = nlmsg_data(nlh);
4554 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4555 	if (!pfx)
4556 		return -EINVAL;
4557 
4558 	if (tb[IFA_CACHEINFO]) {
4559 		struct ifa_cacheinfo *ci;
4560 
4561 		ci = nla_data(tb[IFA_CACHEINFO]);
4562 		valid_lft = ci->ifa_valid;
4563 		preferred_lft = ci->ifa_prefered;
4564 	} else {
4565 		preferred_lft = INFINITY_LIFE_TIME;
4566 		valid_lft = INFINITY_LIFE_TIME;
4567 	}
4568 
4569 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4570 	if (!dev)
4571 		return -ENODEV;
4572 
4573 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4574 
4575 	/* We ignore other flags so far. */
4576 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4577 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4578 
4579 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4580 	if (!ifa) {
4581 		/*
4582 		 * It would be best to check for !NLM_F_CREATE here but
4583 		 * userspace already relies on not having to provide this.
4584 		 */
4585 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4586 				      ifm->ifa_prefixlen, ifa_flags,
4587 				      preferred_lft, valid_lft, extack);
4588 	}
4589 
4590 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4591 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4592 		err = -EEXIST;
4593 	else
4594 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4595 
4596 	in6_ifa_put(ifa);
4597 
4598 	return err;
4599 }
4600 
4601 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4602 			  u8 scope, int ifindex)
4603 {
4604 	struct ifaddrmsg *ifm;
4605 
4606 	ifm = nlmsg_data(nlh);
4607 	ifm->ifa_family = AF_INET6;
4608 	ifm->ifa_prefixlen = prefixlen;
4609 	ifm->ifa_flags = flags;
4610 	ifm->ifa_scope = scope;
4611 	ifm->ifa_index = ifindex;
4612 }
4613 
4614 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4615 			 unsigned long tstamp, u32 preferred, u32 valid)
4616 {
4617 	struct ifa_cacheinfo ci;
4618 
4619 	ci.cstamp = cstamp_delta(cstamp);
4620 	ci.tstamp = cstamp_delta(tstamp);
4621 	ci.ifa_prefered = preferred;
4622 	ci.ifa_valid = valid;
4623 
4624 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4625 }
4626 
4627 static inline int rt_scope(int ifa_scope)
4628 {
4629 	if (ifa_scope & IFA_HOST)
4630 		return RT_SCOPE_HOST;
4631 	else if (ifa_scope & IFA_LINK)
4632 		return RT_SCOPE_LINK;
4633 	else if (ifa_scope & IFA_SITE)
4634 		return RT_SCOPE_SITE;
4635 	else
4636 		return RT_SCOPE_UNIVERSE;
4637 }
4638 
4639 static inline int inet6_ifaddr_msgsize(void)
4640 {
4641 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4642 	       + nla_total_size(16) /* IFA_LOCAL */
4643 	       + nla_total_size(16) /* IFA_ADDRESS */
4644 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4645 	       + nla_total_size(4)  /* IFA_FLAGS */;
4646 }
4647 
4648 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4649 			     u32 portid, u32 seq, int event, unsigned int flags)
4650 {
4651 	struct nlmsghdr  *nlh;
4652 	u32 preferred, valid;
4653 
4654 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4655 	if (!nlh)
4656 		return -EMSGSIZE;
4657 
4658 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4659 		      ifa->idev->dev->ifindex);
4660 
4661 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4662 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4663 		preferred = ifa->prefered_lft;
4664 		valid = ifa->valid_lft;
4665 		if (preferred != INFINITY_LIFE_TIME) {
4666 			long tval = (jiffies - ifa->tstamp)/HZ;
4667 			if (preferred > tval)
4668 				preferred -= tval;
4669 			else
4670 				preferred = 0;
4671 			if (valid != INFINITY_LIFE_TIME) {
4672 				if (valid > tval)
4673 					valid -= tval;
4674 				else
4675 					valid = 0;
4676 			}
4677 		}
4678 	} else {
4679 		preferred = INFINITY_LIFE_TIME;
4680 		valid = INFINITY_LIFE_TIME;
4681 	}
4682 
4683 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4684 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4685 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4686 			goto error;
4687 	} else
4688 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4689 			goto error;
4690 
4691 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4692 		goto error;
4693 
4694 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4695 		goto error;
4696 
4697 	nlmsg_end(skb, nlh);
4698 	return 0;
4699 
4700 error:
4701 	nlmsg_cancel(skb, nlh);
4702 	return -EMSGSIZE;
4703 }
4704 
4705 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4706 				u32 portid, u32 seq, int event, u16 flags)
4707 {
4708 	struct nlmsghdr  *nlh;
4709 	u8 scope = RT_SCOPE_UNIVERSE;
4710 	int ifindex = ifmca->idev->dev->ifindex;
4711 
4712 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4713 		scope = RT_SCOPE_SITE;
4714 
4715 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4716 	if (!nlh)
4717 		return -EMSGSIZE;
4718 
4719 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4720 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4721 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4722 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4723 		nlmsg_cancel(skb, nlh);
4724 		return -EMSGSIZE;
4725 	}
4726 
4727 	nlmsg_end(skb, nlh);
4728 	return 0;
4729 }
4730 
4731 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4732 				u32 portid, u32 seq, int event, unsigned int flags)
4733 {
4734 	struct nlmsghdr  *nlh;
4735 	u8 scope = RT_SCOPE_UNIVERSE;
4736 	int ifindex = ifaca->aca_idev->dev->ifindex;
4737 
4738 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4739 		scope = RT_SCOPE_SITE;
4740 
4741 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4742 	if (!nlh)
4743 		return -EMSGSIZE;
4744 
4745 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4746 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4747 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4748 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4749 		nlmsg_cancel(skb, nlh);
4750 		return -EMSGSIZE;
4751 	}
4752 
4753 	nlmsg_end(skb, nlh);
4754 	return 0;
4755 }
4756 
4757 enum addr_type_t {
4758 	UNICAST_ADDR,
4759 	MULTICAST_ADDR,
4760 	ANYCAST_ADDR,
4761 };
4762 
4763 /* called with rcu_read_lock() */
4764 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4765 			  struct netlink_callback *cb, enum addr_type_t type,
4766 			  int s_ip_idx, int *p_ip_idx)
4767 {
4768 	struct ifmcaddr6 *ifmca;
4769 	struct ifacaddr6 *ifaca;
4770 	int err = 1;
4771 	int ip_idx = *p_ip_idx;
4772 
4773 	read_lock_bh(&idev->lock);
4774 	switch (type) {
4775 	case UNICAST_ADDR: {
4776 		struct inet6_ifaddr *ifa;
4777 
4778 		/* unicast address incl. temp addr */
4779 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4780 			if (++ip_idx < s_ip_idx)
4781 				continue;
4782 			err = inet6_fill_ifaddr(skb, ifa,
4783 						NETLINK_CB(cb->skb).portid,
4784 						cb->nlh->nlmsg_seq,
4785 						RTM_NEWADDR,
4786 						NLM_F_MULTI);
4787 			if (err < 0)
4788 				break;
4789 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4790 		}
4791 		break;
4792 	}
4793 	case MULTICAST_ADDR:
4794 		/* multicast address */
4795 		for (ifmca = idev->mc_list; ifmca;
4796 		     ifmca = ifmca->next, ip_idx++) {
4797 			if (ip_idx < s_ip_idx)
4798 				continue;
4799 			err = inet6_fill_ifmcaddr(skb, ifmca,
4800 						  NETLINK_CB(cb->skb).portid,
4801 						  cb->nlh->nlmsg_seq,
4802 						  RTM_GETMULTICAST,
4803 						  NLM_F_MULTI);
4804 			if (err < 0)
4805 				break;
4806 		}
4807 		break;
4808 	case ANYCAST_ADDR:
4809 		/* anycast address */
4810 		for (ifaca = idev->ac_list; ifaca;
4811 		     ifaca = ifaca->aca_next, ip_idx++) {
4812 			if (ip_idx < s_ip_idx)
4813 				continue;
4814 			err = inet6_fill_ifacaddr(skb, ifaca,
4815 						  NETLINK_CB(cb->skb).portid,
4816 						  cb->nlh->nlmsg_seq,
4817 						  RTM_GETANYCAST,
4818 						  NLM_F_MULTI);
4819 			if (err < 0)
4820 				break;
4821 		}
4822 		break;
4823 	default:
4824 		break;
4825 	}
4826 	read_unlock_bh(&idev->lock);
4827 	*p_ip_idx = ip_idx;
4828 	return err;
4829 }
4830 
4831 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4832 			   enum addr_type_t type)
4833 {
4834 	struct net *net = sock_net(skb->sk);
4835 	int h, s_h;
4836 	int idx, ip_idx;
4837 	int s_idx, s_ip_idx;
4838 	struct net_device *dev;
4839 	struct inet6_dev *idev;
4840 	struct hlist_head *head;
4841 
4842 	s_h = cb->args[0];
4843 	s_idx = idx = cb->args[1];
4844 	s_ip_idx = ip_idx = cb->args[2];
4845 
4846 	rcu_read_lock();
4847 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4848 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4849 		idx = 0;
4850 		head = &net->dev_index_head[h];
4851 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4852 			if (idx < s_idx)
4853 				goto cont;
4854 			if (h > s_h || idx > s_idx)
4855 				s_ip_idx = 0;
4856 			ip_idx = 0;
4857 			idev = __in6_dev_get(dev);
4858 			if (!idev)
4859 				goto cont;
4860 
4861 			if (in6_dump_addrs(idev, skb, cb, type,
4862 					   s_ip_idx, &ip_idx) < 0)
4863 				goto done;
4864 cont:
4865 			idx++;
4866 		}
4867 	}
4868 done:
4869 	rcu_read_unlock();
4870 	cb->args[0] = h;
4871 	cb->args[1] = idx;
4872 	cb->args[2] = ip_idx;
4873 
4874 	return skb->len;
4875 }
4876 
4877 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4878 {
4879 	enum addr_type_t type = UNICAST_ADDR;
4880 
4881 	return inet6_dump_addr(skb, cb, type);
4882 }
4883 
4884 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4885 {
4886 	enum addr_type_t type = MULTICAST_ADDR;
4887 
4888 	return inet6_dump_addr(skb, cb, type);
4889 }
4890 
4891 
4892 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4893 {
4894 	enum addr_type_t type = ANYCAST_ADDR;
4895 
4896 	return inet6_dump_addr(skb, cb, type);
4897 }
4898 
4899 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4900 			     struct netlink_ext_ack *extack)
4901 {
4902 	struct net *net = sock_net(in_skb->sk);
4903 	struct ifaddrmsg *ifm;
4904 	struct nlattr *tb[IFA_MAX+1];
4905 	struct in6_addr *addr = NULL, *peer;
4906 	struct net_device *dev = NULL;
4907 	struct inet6_ifaddr *ifa;
4908 	struct sk_buff *skb;
4909 	int err;
4910 
4911 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4912 			  extack);
4913 	if (err < 0)
4914 		return err;
4915 
4916 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4917 	if (!addr)
4918 		return -EINVAL;
4919 
4920 	ifm = nlmsg_data(nlh);
4921 	if (ifm->ifa_index)
4922 		dev = dev_get_by_index(net, ifm->ifa_index);
4923 
4924 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4925 	if (!ifa) {
4926 		err = -EADDRNOTAVAIL;
4927 		goto errout;
4928 	}
4929 
4930 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4931 	if (!skb) {
4932 		err = -ENOBUFS;
4933 		goto errout_ifa;
4934 	}
4935 
4936 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4937 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4938 	if (err < 0) {
4939 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4940 		WARN_ON(err == -EMSGSIZE);
4941 		kfree_skb(skb);
4942 		goto errout_ifa;
4943 	}
4944 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4945 errout_ifa:
4946 	in6_ifa_put(ifa);
4947 errout:
4948 	if (dev)
4949 		dev_put(dev);
4950 	return err;
4951 }
4952 
4953 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4954 {
4955 	struct sk_buff *skb;
4956 	struct net *net = dev_net(ifa->idev->dev);
4957 	int err = -ENOBUFS;
4958 
4959 	/* Don't send DELADDR notification for TENTATIVE address,
4960 	 * since NEWADDR notification is sent only after removing
4961 	 * TENTATIVE flag, if DAD has not failed.
4962 	 */
4963 	if (ifa->flags & IFA_F_TENTATIVE && !(ifa->flags & IFA_F_DADFAILED) &&
4964 	    event == RTM_DELADDR)
4965 		return;
4966 
4967 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4968 	if (!skb)
4969 		goto errout;
4970 
4971 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4972 	if (err < 0) {
4973 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4974 		WARN_ON(err == -EMSGSIZE);
4975 		kfree_skb(skb);
4976 		goto errout;
4977 	}
4978 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
4979 	return;
4980 errout:
4981 	if (err < 0)
4982 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
4983 }
4984 
4985 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
4986 				__s32 *array, int bytes)
4987 {
4988 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4989 
4990 	memset(array, 0, bytes);
4991 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4992 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4993 	array[DEVCONF_MTU6] = cnf->mtu6;
4994 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4995 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4996 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4997 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4998 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4999 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5000 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5001 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5002 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5003 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5004 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5005 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5006 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5007 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5008 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5009 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5010 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5011 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5012 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5013 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5014 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5015 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5016 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5017 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5018 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5019 #ifdef CONFIG_IPV6_ROUTER_PREF
5020 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5021 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5022 		jiffies_to_msecs(cnf->rtr_probe_interval);
5023 #ifdef CONFIG_IPV6_ROUTE_INFO
5024 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5025 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5026 #endif
5027 #endif
5028 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5029 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5030 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5031 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5032 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5033 #endif
5034 #ifdef CONFIG_IPV6_MROUTE
5035 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5036 #endif
5037 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5038 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5039 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5040 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5041 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5042 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5043 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5044 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5045 	/* we omit DEVCONF_STABLE_SECRET for now */
5046 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5047 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5048 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5049 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5050 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5051 #ifdef CONFIG_IPV6_SEG6_HMAC
5052 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5053 #endif
5054 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5055 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5056 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5057 }
5058 
5059 static inline size_t inet6_ifla6_size(void)
5060 {
5061 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5062 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5063 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5064 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5065 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5066 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5067 }
5068 
5069 static inline size_t inet6_if_nlmsg_size(void)
5070 {
5071 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5072 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5073 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5074 	       + nla_total_size(4) /* IFLA_MTU */
5075 	       + nla_total_size(4) /* IFLA_LINK */
5076 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5077 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5078 }
5079 
5080 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5081 					int bytes)
5082 {
5083 	int i;
5084 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5085 	BUG_ON(pad < 0);
5086 
5087 	/* Use put_unaligned() because stats may not be aligned for u64. */
5088 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5089 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5090 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5091 
5092 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5093 }
5094 
5095 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5096 					int bytes, size_t syncpoff)
5097 {
5098 	int i, c;
5099 	u64 buff[IPSTATS_MIB_MAX];
5100 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5101 
5102 	BUG_ON(pad < 0);
5103 
5104 	memset(buff, 0, sizeof(buff));
5105 	buff[0] = IPSTATS_MIB_MAX;
5106 
5107 	for_each_possible_cpu(c) {
5108 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5109 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5110 	}
5111 
5112 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5113 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5114 }
5115 
5116 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5117 			     int bytes)
5118 {
5119 	switch (attrtype) {
5120 	case IFLA_INET6_STATS:
5121 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5122 				     offsetof(struct ipstats_mib, syncp));
5123 		break;
5124 	case IFLA_INET6_ICMP6STATS:
5125 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5126 		break;
5127 	}
5128 }
5129 
5130 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5131 				  u32 ext_filter_mask)
5132 {
5133 	struct nlattr *nla;
5134 	struct ifla_cacheinfo ci;
5135 
5136 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5137 		goto nla_put_failure;
5138 	ci.max_reasm_len = IPV6_MAXPLEN;
5139 	ci.tstamp = cstamp_delta(idev->tstamp);
5140 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5141 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5142 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5143 		goto nla_put_failure;
5144 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5145 	if (!nla)
5146 		goto nla_put_failure;
5147 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5148 
5149 	/* XXX - MC not implemented */
5150 
5151 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5152 		return 0;
5153 
5154 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5155 	if (!nla)
5156 		goto nla_put_failure;
5157 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5158 
5159 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5160 	if (!nla)
5161 		goto nla_put_failure;
5162 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5163 
5164 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5165 	if (!nla)
5166 		goto nla_put_failure;
5167 
5168 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5169 		goto nla_put_failure;
5170 
5171 	read_lock_bh(&idev->lock);
5172 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5173 	read_unlock_bh(&idev->lock);
5174 
5175 	return 0;
5176 
5177 nla_put_failure:
5178 	return -EMSGSIZE;
5179 }
5180 
5181 static size_t inet6_get_link_af_size(const struct net_device *dev,
5182 				     u32 ext_filter_mask)
5183 {
5184 	if (!__in6_dev_get(dev))
5185 		return 0;
5186 
5187 	return inet6_ifla6_size();
5188 }
5189 
5190 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5191 			      u32 ext_filter_mask)
5192 {
5193 	struct inet6_dev *idev = __in6_dev_get(dev);
5194 
5195 	if (!idev)
5196 		return -ENODATA;
5197 
5198 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5199 		return -EMSGSIZE;
5200 
5201 	return 0;
5202 }
5203 
5204 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5205 {
5206 	struct inet6_ifaddr *ifp;
5207 	struct net_device *dev = idev->dev;
5208 	bool clear_token, update_rs = false;
5209 	struct in6_addr ll_addr;
5210 
5211 	ASSERT_RTNL();
5212 
5213 	if (!token)
5214 		return -EINVAL;
5215 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5216 		return -EINVAL;
5217 	if (!ipv6_accept_ra(idev))
5218 		return -EINVAL;
5219 	if (idev->cnf.rtr_solicits == 0)
5220 		return -EINVAL;
5221 
5222 	write_lock_bh(&idev->lock);
5223 
5224 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5225 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5226 
5227 	write_unlock_bh(&idev->lock);
5228 
5229 	clear_token = ipv6_addr_any(token);
5230 	if (clear_token)
5231 		goto update_lft;
5232 
5233 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5234 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5235 			     IFA_F_OPTIMISTIC)) {
5236 		/* If we're not ready, then normal ifup will take care
5237 		 * of this. Otherwise, we need to request our rs here.
5238 		 */
5239 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5240 		update_rs = true;
5241 	}
5242 
5243 update_lft:
5244 	write_lock_bh(&idev->lock);
5245 
5246 	if (update_rs) {
5247 		idev->if_flags |= IF_RS_SENT;
5248 		idev->rs_interval = rfc3315_s14_backoff_init(
5249 			idev->cnf.rtr_solicit_interval);
5250 		idev->rs_probes = 1;
5251 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5252 	}
5253 
5254 	/* Well, that's kinda nasty ... */
5255 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5256 		spin_lock(&ifp->lock);
5257 		if (ifp->tokenized) {
5258 			ifp->valid_lft = 0;
5259 			ifp->prefered_lft = 0;
5260 		}
5261 		spin_unlock(&ifp->lock);
5262 	}
5263 
5264 	write_unlock_bh(&idev->lock);
5265 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5266 	addrconf_verify_rtnl();
5267 	return 0;
5268 }
5269 
5270 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5271 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5272 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5273 };
5274 
5275 static int inet6_validate_link_af(const struct net_device *dev,
5276 				  const struct nlattr *nla)
5277 {
5278 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5279 
5280 	if (dev && !__in6_dev_get(dev))
5281 		return -EAFNOSUPPORT;
5282 
5283 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5284 				NULL);
5285 }
5286 
5287 static int check_addr_gen_mode(int mode)
5288 {
5289 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5290 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5291 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5292 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5293 		return -EINVAL;
5294 	return 1;
5295 }
5296 
5297 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5298 				int mode)
5299 {
5300 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5301 	    !idev->cnf.stable_secret.initialized &&
5302 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5303 		return -EINVAL;
5304 	return 1;
5305 }
5306 
5307 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5308 {
5309 	int err = -EINVAL;
5310 	struct inet6_dev *idev = __in6_dev_get(dev);
5311 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5312 
5313 	if (!idev)
5314 		return -EAFNOSUPPORT;
5315 
5316 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5317 		BUG();
5318 
5319 	if (tb[IFLA_INET6_TOKEN]) {
5320 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5321 		if (err)
5322 			return err;
5323 	}
5324 
5325 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5326 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5327 
5328 		if (check_addr_gen_mode(mode) < 0 ||
5329 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5330 			return -EINVAL;
5331 
5332 		idev->cnf.addr_gen_mode = mode;
5333 		err = 0;
5334 	}
5335 
5336 	return err;
5337 }
5338 
5339 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5340 			     u32 portid, u32 seq, int event, unsigned int flags)
5341 {
5342 	struct net_device *dev = idev->dev;
5343 	struct ifinfomsg *hdr;
5344 	struct nlmsghdr *nlh;
5345 	void *protoinfo;
5346 
5347 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5348 	if (!nlh)
5349 		return -EMSGSIZE;
5350 
5351 	hdr = nlmsg_data(nlh);
5352 	hdr->ifi_family = AF_INET6;
5353 	hdr->__ifi_pad = 0;
5354 	hdr->ifi_type = dev->type;
5355 	hdr->ifi_index = dev->ifindex;
5356 	hdr->ifi_flags = dev_get_flags(dev);
5357 	hdr->ifi_change = 0;
5358 
5359 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5360 	    (dev->addr_len &&
5361 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5362 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5363 	    (dev->ifindex != dev_get_iflink(dev) &&
5364 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5365 	    nla_put_u8(skb, IFLA_OPERSTATE,
5366 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5367 		goto nla_put_failure;
5368 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5369 	if (!protoinfo)
5370 		goto nla_put_failure;
5371 
5372 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5373 		goto nla_put_failure;
5374 
5375 	nla_nest_end(skb, protoinfo);
5376 	nlmsg_end(skb, nlh);
5377 	return 0;
5378 
5379 nla_put_failure:
5380 	nlmsg_cancel(skb, nlh);
5381 	return -EMSGSIZE;
5382 }
5383 
5384 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5385 {
5386 	struct net *net = sock_net(skb->sk);
5387 	int h, s_h;
5388 	int idx = 0, s_idx;
5389 	struct net_device *dev;
5390 	struct inet6_dev *idev;
5391 	struct hlist_head *head;
5392 
5393 	s_h = cb->args[0];
5394 	s_idx = cb->args[1];
5395 
5396 	rcu_read_lock();
5397 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5398 		idx = 0;
5399 		head = &net->dev_index_head[h];
5400 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5401 			if (idx < s_idx)
5402 				goto cont;
5403 			idev = __in6_dev_get(dev);
5404 			if (!idev)
5405 				goto cont;
5406 			if (inet6_fill_ifinfo(skb, idev,
5407 					      NETLINK_CB(cb->skb).portid,
5408 					      cb->nlh->nlmsg_seq,
5409 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5410 				goto out;
5411 cont:
5412 			idx++;
5413 		}
5414 	}
5415 out:
5416 	rcu_read_unlock();
5417 	cb->args[1] = idx;
5418 	cb->args[0] = h;
5419 
5420 	return skb->len;
5421 }
5422 
5423 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5424 {
5425 	struct sk_buff *skb;
5426 	struct net *net = dev_net(idev->dev);
5427 	int err = -ENOBUFS;
5428 
5429 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5430 	if (!skb)
5431 		goto errout;
5432 
5433 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5434 	if (err < 0) {
5435 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5436 		WARN_ON(err == -EMSGSIZE);
5437 		kfree_skb(skb);
5438 		goto errout;
5439 	}
5440 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5441 	return;
5442 errout:
5443 	if (err < 0)
5444 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5445 }
5446 
5447 static inline size_t inet6_prefix_nlmsg_size(void)
5448 {
5449 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5450 	       + nla_total_size(sizeof(struct in6_addr))
5451 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5452 }
5453 
5454 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5455 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5456 			     int event, unsigned int flags)
5457 {
5458 	struct prefixmsg *pmsg;
5459 	struct nlmsghdr *nlh;
5460 	struct prefix_cacheinfo	ci;
5461 
5462 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5463 	if (!nlh)
5464 		return -EMSGSIZE;
5465 
5466 	pmsg = nlmsg_data(nlh);
5467 	pmsg->prefix_family = AF_INET6;
5468 	pmsg->prefix_pad1 = 0;
5469 	pmsg->prefix_pad2 = 0;
5470 	pmsg->prefix_ifindex = idev->dev->ifindex;
5471 	pmsg->prefix_len = pinfo->prefix_len;
5472 	pmsg->prefix_type = pinfo->type;
5473 	pmsg->prefix_pad3 = 0;
5474 	pmsg->prefix_flags = 0;
5475 	if (pinfo->onlink)
5476 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5477 	if (pinfo->autoconf)
5478 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5479 
5480 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5481 		goto nla_put_failure;
5482 	ci.preferred_time = ntohl(pinfo->prefered);
5483 	ci.valid_time = ntohl(pinfo->valid);
5484 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5485 		goto nla_put_failure;
5486 	nlmsg_end(skb, nlh);
5487 	return 0;
5488 
5489 nla_put_failure:
5490 	nlmsg_cancel(skb, nlh);
5491 	return -EMSGSIZE;
5492 }
5493 
5494 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5495 			 struct prefix_info *pinfo)
5496 {
5497 	struct sk_buff *skb;
5498 	struct net *net = dev_net(idev->dev);
5499 	int err = -ENOBUFS;
5500 
5501 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5502 	if (!skb)
5503 		goto errout;
5504 
5505 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5506 	if (err < 0) {
5507 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5508 		WARN_ON(err == -EMSGSIZE);
5509 		kfree_skb(skb);
5510 		goto errout;
5511 	}
5512 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5513 	return;
5514 errout:
5515 	if (err < 0)
5516 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5517 }
5518 
5519 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5520 {
5521 	struct net *net = dev_net(ifp->idev->dev);
5522 
5523 	if (event)
5524 		ASSERT_RTNL();
5525 
5526 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5527 
5528 	switch (event) {
5529 	case RTM_NEWADDR:
5530 		/*
5531 		 * If the address was optimistic
5532 		 * we inserted the route at the start of
5533 		 * our DAD process, so we don't need
5534 		 * to do it again
5535 		 */
5536 		if (!rcu_access_pointer(ifp->rt->rt6i_node))
5537 			ip6_ins_rt(ifp->rt);
5538 		if (ifp->idev->cnf.forwarding)
5539 			addrconf_join_anycast(ifp);
5540 		if (!ipv6_addr_any(&ifp->peer_addr))
5541 			addrconf_prefix_route(&ifp->peer_addr, 128,
5542 					      ifp->idev->dev, 0, 0);
5543 		break;
5544 	case RTM_DELADDR:
5545 		if (ifp->idev->cnf.forwarding)
5546 			addrconf_leave_anycast(ifp);
5547 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5548 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5549 			struct rt6_info *rt;
5550 
5551 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5552 						       ifp->idev->dev, 0, 0);
5553 			if (rt)
5554 				ip6_del_rt(rt);
5555 		}
5556 		if (ifp->rt) {
5557 			if (dst_hold_safe(&ifp->rt->dst))
5558 				ip6_del_rt(ifp->rt);
5559 		}
5560 		rt_genid_bump_ipv6(net);
5561 		break;
5562 	}
5563 	atomic_inc(&net->ipv6.dev_addr_genid);
5564 }
5565 
5566 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5567 {
5568 	rcu_read_lock_bh();
5569 	if (likely(ifp->idev->dead == 0))
5570 		__ipv6_ifa_notify(event, ifp);
5571 	rcu_read_unlock_bh();
5572 }
5573 
5574 #ifdef CONFIG_SYSCTL
5575 
5576 static
5577 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5578 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5579 {
5580 	int *valp = ctl->data;
5581 	int val = *valp;
5582 	loff_t pos = *ppos;
5583 	struct ctl_table lctl;
5584 	int ret;
5585 
5586 	/*
5587 	 * ctl->data points to idev->cnf.forwarding, we should
5588 	 * not modify it until we get the rtnl lock.
5589 	 */
5590 	lctl = *ctl;
5591 	lctl.data = &val;
5592 
5593 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5594 
5595 	if (write)
5596 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5597 	if (ret)
5598 		*ppos = pos;
5599 	return ret;
5600 }
5601 
5602 static
5603 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5604 			void __user *buffer, size_t *lenp, loff_t *ppos)
5605 {
5606 	struct inet6_dev *idev = ctl->extra1;
5607 	int min_mtu = IPV6_MIN_MTU;
5608 	struct ctl_table lctl;
5609 
5610 	lctl = *ctl;
5611 	lctl.extra1 = &min_mtu;
5612 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5613 
5614 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5615 }
5616 
5617 static void dev_disable_change(struct inet6_dev *idev)
5618 {
5619 	struct netdev_notifier_info info;
5620 
5621 	if (!idev || !idev->dev)
5622 		return;
5623 
5624 	netdev_notifier_info_init(&info, idev->dev);
5625 	if (idev->cnf.disable_ipv6)
5626 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5627 	else
5628 		addrconf_notify(NULL, NETDEV_UP, &info);
5629 }
5630 
5631 static void addrconf_disable_change(struct net *net, __s32 newf)
5632 {
5633 	struct net_device *dev;
5634 	struct inet6_dev *idev;
5635 
5636 	for_each_netdev(net, dev) {
5637 		idev = __in6_dev_get(dev);
5638 		if (idev) {
5639 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5640 			idev->cnf.disable_ipv6 = newf;
5641 			if (changed)
5642 				dev_disable_change(idev);
5643 		}
5644 	}
5645 }
5646 
5647 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5648 {
5649 	struct net *net;
5650 	int old;
5651 
5652 	if (!rtnl_trylock())
5653 		return restart_syscall();
5654 
5655 	net = (struct net *)table->extra2;
5656 	old = *p;
5657 	*p = newf;
5658 
5659 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5660 		rtnl_unlock();
5661 		return 0;
5662 	}
5663 
5664 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5665 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5666 		addrconf_disable_change(net, newf);
5667 	} else if ((!newf) ^ (!old))
5668 		dev_disable_change((struct inet6_dev *)table->extra1);
5669 
5670 	rtnl_unlock();
5671 	return 0;
5672 }
5673 
5674 static
5675 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5676 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5677 {
5678 	int *valp = ctl->data;
5679 	int val = *valp;
5680 	loff_t pos = *ppos;
5681 	struct ctl_table lctl;
5682 	int ret;
5683 
5684 	/*
5685 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5686 	 * not modify it until we get the rtnl lock.
5687 	 */
5688 	lctl = *ctl;
5689 	lctl.data = &val;
5690 
5691 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5692 
5693 	if (write)
5694 		ret = addrconf_disable_ipv6(ctl, valp, val);
5695 	if (ret)
5696 		*ppos = pos;
5697 	return ret;
5698 }
5699 
5700 static
5701 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5702 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5703 {
5704 	int *valp = ctl->data;
5705 	int ret;
5706 	int old, new;
5707 
5708 	old = *valp;
5709 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5710 	new = *valp;
5711 
5712 	if (write && old != new) {
5713 		struct net *net = ctl->extra2;
5714 
5715 		if (!rtnl_trylock())
5716 			return restart_syscall();
5717 
5718 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5719 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5720 						     NETCONFA_PROXY_NEIGH,
5721 						     NETCONFA_IFINDEX_DEFAULT,
5722 						     net->ipv6.devconf_dflt);
5723 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5724 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5725 						     NETCONFA_PROXY_NEIGH,
5726 						     NETCONFA_IFINDEX_ALL,
5727 						     net->ipv6.devconf_all);
5728 		else {
5729 			struct inet6_dev *idev = ctl->extra1;
5730 
5731 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5732 						     NETCONFA_PROXY_NEIGH,
5733 						     idev->dev->ifindex,
5734 						     &idev->cnf);
5735 		}
5736 		rtnl_unlock();
5737 	}
5738 
5739 	return ret;
5740 }
5741 
5742 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5743 					 void __user *buffer, size_t *lenp,
5744 					 loff_t *ppos)
5745 {
5746 	int ret = 0;
5747 	int new_val;
5748 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5749 	struct net *net = (struct net *)ctl->extra2;
5750 
5751 	if (!rtnl_trylock())
5752 		return restart_syscall();
5753 
5754 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5755 
5756 	if (write) {
5757 		new_val = *((int *)ctl->data);
5758 
5759 		if (check_addr_gen_mode(new_val) < 0) {
5760 			ret = -EINVAL;
5761 			goto out;
5762 		}
5763 
5764 		/* request for default */
5765 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5766 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5767 
5768 		/* request for individual net device */
5769 		} else {
5770 			if (!idev)
5771 				goto out;
5772 
5773 			if (check_stable_privacy(idev, net, new_val) < 0) {
5774 				ret = -EINVAL;
5775 				goto out;
5776 			}
5777 
5778 			if (idev->cnf.addr_gen_mode != new_val) {
5779 				idev->cnf.addr_gen_mode = new_val;
5780 				addrconf_dev_config(idev->dev);
5781 			}
5782 		}
5783 	}
5784 
5785 out:
5786 	rtnl_unlock();
5787 
5788 	return ret;
5789 }
5790 
5791 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5792 					 void __user *buffer, size_t *lenp,
5793 					 loff_t *ppos)
5794 {
5795 	int err;
5796 	struct in6_addr addr;
5797 	char str[IPV6_MAX_STRLEN];
5798 	struct ctl_table lctl = *ctl;
5799 	struct net *net = ctl->extra2;
5800 	struct ipv6_stable_secret *secret = ctl->data;
5801 
5802 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5803 		return -EIO;
5804 
5805 	lctl.maxlen = IPV6_MAX_STRLEN;
5806 	lctl.data = str;
5807 
5808 	if (!rtnl_trylock())
5809 		return restart_syscall();
5810 
5811 	if (!write && !secret->initialized) {
5812 		err = -EIO;
5813 		goto out;
5814 	}
5815 
5816 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5817 	if (err >= sizeof(str)) {
5818 		err = -EIO;
5819 		goto out;
5820 	}
5821 
5822 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5823 	if (err || !write)
5824 		goto out;
5825 
5826 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5827 		err = -EIO;
5828 		goto out;
5829 	}
5830 
5831 	secret->initialized = true;
5832 	secret->secret = addr;
5833 
5834 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5835 		struct net_device *dev;
5836 
5837 		for_each_netdev(net, dev) {
5838 			struct inet6_dev *idev = __in6_dev_get(dev);
5839 
5840 			if (idev) {
5841 				idev->cnf.addr_gen_mode =
5842 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5843 			}
5844 		}
5845 	} else {
5846 		struct inet6_dev *idev = ctl->extra1;
5847 
5848 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5849 	}
5850 
5851 out:
5852 	rtnl_unlock();
5853 
5854 	return err;
5855 }
5856 
5857 static
5858 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5859 						int write,
5860 						void __user *buffer,
5861 						size_t *lenp,
5862 						loff_t *ppos)
5863 {
5864 	int *valp = ctl->data;
5865 	int val = *valp;
5866 	loff_t pos = *ppos;
5867 	struct ctl_table lctl;
5868 	int ret;
5869 
5870 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5871 	 * we should not modify it until we get the rtnl lock.
5872 	 */
5873 	lctl = *ctl;
5874 	lctl.data = &val;
5875 
5876 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5877 
5878 	if (write)
5879 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5880 	if (ret)
5881 		*ppos = pos;
5882 	return ret;
5883 }
5884 
5885 static
5886 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5887 {
5888 	if (rt) {
5889 		if (action)
5890 			rt->dst.flags |= DST_NOPOLICY;
5891 		else
5892 			rt->dst.flags &= ~DST_NOPOLICY;
5893 	}
5894 }
5895 
5896 static
5897 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5898 {
5899 	struct inet6_ifaddr *ifa;
5900 
5901 	read_lock_bh(&idev->lock);
5902 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5903 		spin_lock(&ifa->lock);
5904 		if (ifa->rt) {
5905 			struct rt6_info *rt = ifa->rt;
5906 			int cpu;
5907 
5908 			rcu_read_lock();
5909 			addrconf_set_nopolicy(ifa->rt, val);
5910 			if (rt->rt6i_pcpu) {
5911 				for_each_possible_cpu(cpu) {
5912 					struct rt6_info **rtp;
5913 
5914 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5915 					addrconf_set_nopolicy(*rtp, val);
5916 				}
5917 			}
5918 			rcu_read_unlock();
5919 		}
5920 		spin_unlock(&ifa->lock);
5921 	}
5922 	read_unlock_bh(&idev->lock);
5923 }
5924 
5925 static
5926 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
5927 {
5928 	struct inet6_dev *idev;
5929 	struct net *net;
5930 
5931 	if (!rtnl_trylock())
5932 		return restart_syscall();
5933 
5934 	*valp = val;
5935 
5936 	net = (struct net *)ctl->extra2;
5937 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
5938 		rtnl_unlock();
5939 		return 0;
5940 	}
5941 
5942 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
5943 		struct net_device *dev;
5944 
5945 		for_each_netdev(net, dev) {
5946 			idev = __in6_dev_get(dev);
5947 			if (idev)
5948 				addrconf_disable_policy_idev(idev, val);
5949 		}
5950 	} else {
5951 		idev = (struct inet6_dev *)ctl->extra1;
5952 		addrconf_disable_policy_idev(idev, val);
5953 	}
5954 
5955 	rtnl_unlock();
5956 	return 0;
5957 }
5958 
5959 static
5960 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
5961 				   void __user *buffer, size_t *lenp,
5962 				   loff_t *ppos)
5963 {
5964 	int *valp = ctl->data;
5965 	int val = *valp;
5966 	loff_t pos = *ppos;
5967 	struct ctl_table lctl;
5968 	int ret;
5969 
5970 	lctl = *ctl;
5971 	lctl.data = &val;
5972 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5973 
5974 	if (write && (*valp != val))
5975 		ret = addrconf_disable_policy(ctl, valp, val);
5976 
5977 	if (ret)
5978 		*ppos = pos;
5979 
5980 	return ret;
5981 }
5982 
5983 static int minus_one = -1;
5984 static const int one = 1;
5985 static const int two_five_five = 255;
5986 
5987 static const struct ctl_table addrconf_sysctl[] = {
5988 	{
5989 		.procname	= "forwarding",
5990 		.data		= &ipv6_devconf.forwarding,
5991 		.maxlen		= sizeof(int),
5992 		.mode		= 0644,
5993 		.proc_handler	= addrconf_sysctl_forward,
5994 	},
5995 	{
5996 		.procname	= "hop_limit",
5997 		.data		= &ipv6_devconf.hop_limit,
5998 		.maxlen		= sizeof(int),
5999 		.mode		= 0644,
6000 		.proc_handler	= proc_dointvec_minmax,
6001 		.extra1		= (void *)&one,
6002 		.extra2		= (void *)&two_five_five,
6003 	},
6004 	{
6005 		.procname	= "mtu",
6006 		.data		= &ipv6_devconf.mtu6,
6007 		.maxlen		= sizeof(int),
6008 		.mode		= 0644,
6009 		.proc_handler	= addrconf_sysctl_mtu,
6010 	},
6011 	{
6012 		.procname	= "accept_ra",
6013 		.data		= &ipv6_devconf.accept_ra,
6014 		.maxlen		= sizeof(int),
6015 		.mode		= 0644,
6016 		.proc_handler	= proc_dointvec,
6017 	},
6018 	{
6019 		.procname	= "accept_redirects",
6020 		.data		= &ipv6_devconf.accept_redirects,
6021 		.maxlen		= sizeof(int),
6022 		.mode		= 0644,
6023 		.proc_handler	= proc_dointvec,
6024 	},
6025 	{
6026 		.procname	= "autoconf",
6027 		.data		= &ipv6_devconf.autoconf,
6028 		.maxlen		= sizeof(int),
6029 		.mode		= 0644,
6030 		.proc_handler	= proc_dointvec,
6031 	},
6032 	{
6033 		.procname	= "dad_transmits",
6034 		.data		= &ipv6_devconf.dad_transmits,
6035 		.maxlen		= sizeof(int),
6036 		.mode		= 0644,
6037 		.proc_handler	= proc_dointvec,
6038 	},
6039 	{
6040 		.procname	= "router_solicitations",
6041 		.data		= &ipv6_devconf.rtr_solicits,
6042 		.maxlen		= sizeof(int),
6043 		.mode		= 0644,
6044 		.proc_handler	= proc_dointvec_minmax,
6045 		.extra1		= &minus_one,
6046 	},
6047 	{
6048 		.procname	= "router_solicitation_interval",
6049 		.data		= &ipv6_devconf.rtr_solicit_interval,
6050 		.maxlen		= sizeof(int),
6051 		.mode		= 0644,
6052 		.proc_handler	= proc_dointvec_jiffies,
6053 	},
6054 	{
6055 		.procname	= "router_solicitation_max_interval",
6056 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6057 		.maxlen		= sizeof(int),
6058 		.mode		= 0644,
6059 		.proc_handler	= proc_dointvec_jiffies,
6060 	},
6061 	{
6062 		.procname	= "router_solicitation_delay",
6063 		.data		= &ipv6_devconf.rtr_solicit_delay,
6064 		.maxlen		= sizeof(int),
6065 		.mode		= 0644,
6066 		.proc_handler	= proc_dointvec_jiffies,
6067 	},
6068 	{
6069 		.procname	= "force_mld_version",
6070 		.data		= &ipv6_devconf.force_mld_version,
6071 		.maxlen		= sizeof(int),
6072 		.mode		= 0644,
6073 		.proc_handler	= proc_dointvec,
6074 	},
6075 	{
6076 		.procname	= "mldv1_unsolicited_report_interval",
6077 		.data		=
6078 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6079 		.maxlen		= sizeof(int),
6080 		.mode		= 0644,
6081 		.proc_handler	= proc_dointvec_ms_jiffies,
6082 	},
6083 	{
6084 		.procname	= "mldv2_unsolicited_report_interval",
6085 		.data		=
6086 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6087 		.maxlen		= sizeof(int),
6088 		.mode		= 0644,
6089 		.proc_handler	= proc_dointvec_ms_jiffies,
6090 	},
6091 	{
6092 		.procname	= "use_tempaddr",
6093 		.data		= &ipv6_devconf.use_tempaddr,
6094 		.maxlen		= sizeof(int),
6095 		.mode		= 0644,
6096 		.proc_handler	= proc_dointvec,
6097 	},
6098 	{
6099 		.procname	= "temp_valid_lft",
6100 		.data		= &ipv6_devconf.temp_valid_lft,
6101 		.maxlen		= sizeof(int),
6102 		.mode		= 0644,
6103 		.proc_handler	= proc_dointvec,
6104 	},
6105 	{
6106 		.procname	= "temp_prefered_lft",
6107 		.data		= &ipv6_devconf.temp_prefered_lft,
6108 		.maxlen		= sizeof(int),
6109 		.mode		= 0644,
6110 		.proc_handler	= proc_dointvec,
6111 	},
6112 	{
6113 		.procname	= "regen_max_retry",
6114 		.data		= &ipv6_devconf.regen_max_retry,
6115 		.maxlen		= sizeof(int),
6116 		.mode		= 0644,
6117 		.proc_handler	= proc_dointvec,
6118 	},
6119 	{
6120 		.procname	= "max_desync_factor",
6121 		.data		= &ipv6_devconf.max_desync_factor,
6122 		.maxlen		= sizeof(int),
6123 		.mode		= 0644,
6124 		.proc_handler	= proc_dointvec,
6125 	},
6126 	{
6127 		.procname	= "max_addresses",
6128 		.data		= &ipv6_devconf.max_addresses,
6129 		.maxlen		= sizeof(int),
6130 		.mode		= 0644,
6131 		.proc_handler	= proc_dointvec,
6132 	},
6133 	{
6134 		.procname	= "accept_ra_defrtr",
6135 		.data		= &ipv6_devconf.accept_ra_defrtr,
6136 		.maxlen		= sizeof(int),
6137 		.mode		= 0644,
6138 		.proc_handler	= proc_dointvec,
6139 	},
6140 	{
6141 		.procname	= "accept_ra_min_hop_limit",
6142 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6143 		.maxlen		= sizeof(int),
6144 		.mode		= 0644,
6145 		.proc_handler	= proc_dointvec,
6146 	},
6147 	{
6148 		.procname	= "accept_ra_pinfo",
6149 		.data		= &ipv6_devconf.accept_ra_pinfo,
6150 		.maxlen		= sizeof(int),
6151 		.mode		= 0644,
6152 		.proc_handler	= proc_dointvec,
6153 	},
6154 #ifdef CONFIG_IPV6_ROUTER_PREF
6155 	{
6156 		.procname	= "accept_ra_rtr_pref",
6157 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6158 		.maxlen		= sizeof(int),
6159 		.mode		= 0644,
6160 		.proc_handler	= proc_dointvec,
6161 	},
6162 	{
6163 		.procname	= "router_probe_interval",
6164 		.data		= &ipv6_devconf.rtr_probe_interval,
6165 		.maxlen		= sizeof(int),
6166 		.mode		= 0644,
6167 		.proc_handler	= proc_dointvec_jiffies,
6168 	},
6169 #ifdef CONFIG_IPV6_ROUTE_INFO
6170 	{
6171 		.procname	= "accept_ra_rt_info_min_plen",
6172 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6173 		.maxlen		= sizeof(int),
6174 		.mode		= 0644,
6175 		.proc_handler	= proc_dointvec,
6176 	},
6177 	{
6178 		.procname	= "accept_ra_rt_info_max_plen",
6179 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6180 		.maxlen		= sizeof(int),
6181 		.mode		= 0644,
6182 		.proc_handler	= proc_dointvec,
6183 	},
6184 #endif
6185 #endif
6186 	{
6187 		.procname	= "proxy_ndp",
6188 		.data		= &ipv6_devconf.proxy_ndp,
6189 		.maxlen		= sizeof(int),
6190 		.mode		= 0644,
6191 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6192 	},
6193 	{
6194 		.procname	= "accept_source_route",
6195 		.data		= &ipv6_devconf.accept_source_route,
6196 		.maxlen		= sizeof(int),
6197 		.mode		= 0644,
6198 		.proc_handler	= proc_dointvec,
6199 	},
6200 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6201 	{
6202 		.procname	= "optimistic_dad",
6203 		.data		= &ipv6_devconf.optimistic_dad,
6204 		.maxlen		= sizeof(int),
6205 		.mode		= 0644,
6206 		.proc_handler   = proc_dointvec,
6207 	},
6208 	{
6209 		.procname	= "use_optimistic",
6210 		.data		= &ipv6_devconf.use_optimistic,
6211 		.maxlen		= sizeof(int),
6212 		.mode		= 0644,
6213 		.proc_handler	= proc_dointvec,
6214 	},
6215 #endif
6216 #ifdef CONFIG_IPV6_MROUTE
6217 	{
6218 		.procname	= "mc_forwarding",
6219 		.data		= &ipv6_devconf.mc_forwarding,
6220 		.maxlen		= sizeof(int),
6221 		.mode		= 0444,
6222 		.proc_handler	= proc_dointvec,
6223 	},
6224 #endif
6225 	{
6226 		.procname	= "disable_ipv6",
6227 		.data		= &ipv6_devconf.disable_ipv6,
6228 		.maxlen		= sizeof(int),
6229 		.mode		= 0644,
6230 		.proc_handler	= addrconf_sysctl_disable,
6231 	},
6232 	{
6233 		.procname	= "accept_dad",
6234 		.data		= &ipv6_devconf.accept_dad,
6235 		.maxlen		= sizeof(int),
6236 		.mode		= 0644,
6237 		.proc_handler	= proc_dointvec,
6238 	},
6239 	{
6240 		.procname	= "force_tllao",
6241 		.data		= &ipv6_devconf.force_tllao,
6242 		.maxlen		= sizeof(int),
6243 		.mode		= 0644,
6244 		.proc_handler	= proc_dointvec
6245 	},
6246 	{
6247 		.procname	= "ndisc_notify",
6248 		.data		= &ipv6_devconf.ndisc_notify,
6249 		.maxlen		= sizeof(int),
6250 		.mode		= 0644,
6251 		.proc_handler	= proc_dointvec
6252 	},
6253 	{
6254 		.procname	= "suppress_frag_ndisc",
6255 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6256 		.maxlen		= sizeof(int),
6257 		.mode		= 0644,
6258 		.proc_handler	= proc_dointvec
6259 	},
6260 	{
6261 		.procname	= "accept_ra_from_local",
6262 		.data		= &ipv6_devconf.accept_ra_from_local,
6263 		.maxlen		= sizeof(int),
6264 		.mode		= 0644,
6265 		.proc_handler	= proc_dointvec,
6266 	},
6267 	{
6268 		.procname	= "accept_ra_mtu",
6269 		.data		= &ipv6_devconf.accept_ra_mtu,
6270 		.maxlen		= sizeof(int),
6271 		.mode		= 0644,
6272 		.proc_handler	= proc_dointvec,
6273 	},
6274 	{
6275 		.procname	= "stable_secret",
6276 		.data		= &ipv6_devconf.stable_secret,
6277 		.maxlen		= IPV6_MAX_STRLEN,
6278 		.mode		= 0600,
6279 		.proc_handler	= addrconf_sysctl_stable_secret,
6280 	},
6281 	{
6282 		.procname	= "use_oif_addrs_only",
6283 		.data		= &ipv6_devconf.use_oif_addrs_only,
6284 		.maxlen		= sizeof(int),
6285 		.mode		= 0644,
6286 		.proc_handler	= proc_dointvec,
6287 	},
6288 	{
6289 		.procname	= "ignore_routes_with_linkdown",
6290 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6291 		.maxlen		= sizeof(int),
6292 		.mode		= 0644,
6293 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6294 	},
6295 	{
6296 		.procname	= "drop_unicast_in_l2_multicast",
6297 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6298 		.maxlen		= sizeof(int),
6299 		.mode		= 0644,
6300 		.proc_handler	= proc_dointvec,
6301 	},
6302 	{
6303 		.procname	= "drop_unsolicited_na",
6304 		.data		= &ipv6_devconf.drop_unsolicited_na,
6305 		.maxlen		= sizeof(int),
6306 		.mode		= 0644,
6307 		.proc_handler	= proc_dointvec,
6308 	},
6309 	{
6310 		.procname	= "keep_addr_on_down",
6311 		.data		= &ipv6_devconf.keep_addr_on_down,
6312 		.maxlen		= sizeof(int),
6313 		.mode		= 0644,
6314 		.proc_handler	= proc_dointvec,
6315 
6316 	},
6317 	{
6318 		.procname	= "seg6_enabled",
6319 		.data		= &ipv6_devconf.seg6_enabled,
6320 		.maxlen		= sizeof(int),
6321 		.mode		= 0644,
6322 		.proc_handler	= proc_dointvec,
6323 	},
6324 #ifdef CONFIG_IPV6_SEG6_HMAC
6325 	{
6326 		.procname	= "seg6_require_hmac",
6327 		.data		= &ipv6_devconf.seg6_require_hmac,
6328 		.maxlen		= sizeof(int),
6329 		.mode		= 0644,
6330 		.proc_handler	= proc_dointvec,
6331 	},
6332 #endif
6333 	{
6334 		.procname       = "enhanced_dad",
6335 		.data           = &ipv6_devconf.enhanced_dad,
6336 		.maxlen         = sizeof(int),
6337 		.mode           = 0644,
6338 		.proc_handler   = proc_dointvec,
6339 	},
6340 	{
6341 		.procname		= "addr_gen_mode",
6342 		.data			= &ipv6_devconf.addr_gen_mode,
6343 		.maxlen			= sizeof(int),
6344 		.mode			= 0644,
6345 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6346 	},
6347 	{
6348 		.procname       = "disable_policy",
6349 		.data           = &ipv6_devconf.disable_policy,
6350 		.maxlen         = sizeof(int),
6351 		.mode           = 0644,
6352 		.proc_handler   = addrconf_sysctl_disable_policy,
6353 	},
6354 	{
6355 		/* sentinel */
6356 	}
6357 };
6358 
6359 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6360 		struct inet6_dev *idev, struct ipv6_devconf *p)
6361 {
6362 	int i, ifindex;
6363 	struct ctl_table *table;
6364 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6365 
6366 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6367 	if (!table)
6368 		goto out;
6369 
6370 	for (i = 0; table[i].data; i++) {
6371 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6372 		/* If one of these is already set, then it is not safe to
6373 		 * overwrite either of them: this makes proc_dointvec_minmax
6374 		 * usable.
6375 		 */
6376 		if (!table[i].extra1 && !table[i].extra2) {
6377 			table[i].extra1 = idev; /* embedded; no ref */
6378 			table[i].extra2 = net;
6379 		}
6380 	}
6381 
6382 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6383 
6384 	p->sysctl_header = register_net_sysctl(net, path, table);
6385 	if (!p->sysctl_header)
6386 		goto free;
6387 
6388 	if (!strcmp(dev_name, "all"))
6389 		ifindex = NETCONFA_IFINDEX_ALL;
6390 	else if (!strcmp(dev_name, "default"))
6391 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6392 	else
6393 		ifindex = idev->dev->ifindex;
6394 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6395 				     ifindex, p);
6396 	return 0;
6397 
6398 free:
6399 	kfree(table);
6400 out:
6401 	return -ENOBUFS;
6402 }
6403 
6404 static void __addrconf_sysctl_unregister(struct net *net,
6405 					 struct ipv6_devconf *p, int ifindex)
6406 {
6407 	struct ctl_table *table;
6408 
6409 	if (!p->sysctl_header)
6410 		return;
6411 
6412 	table = p->sysctl_header->ctl_table_arg;
6413 	unregister_net_sysctl_table(p->sysctl_header);
6414 	p->sysctl_header = NULL;
6415 	kfree(table);
6416 
6417 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6418 }
6419 
6420 static int addrconf_sysctl_register(struct inet6_dev *idev)
6421 {
6422 	int err;
6423 
6424 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6425 		return -EINVAL;
6426 
6427 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6428 				    &ndisc_ifinfo_sysctl_change);
6429 	if (err)
6430 		return err;
6431 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6432 					 idev, &idev->cnf);
6433 	if (err)
6434 		neigh_sysctl_unregister(idev->nd_parms);
6435 
6436 	return err;
6437 }
6438 
6439 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6440 {
6441 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6442 				     idev->dev->ifindex);
6443 	neigh_sysctl_unregister(idev->nd_parms);
6444 }
6445 
6446 
6447 #endif
6448 
6449 static int __net_init addrconf_init_net(struct net *net)
6450 {
6451 	int err = -ENOMEM;
6452 	struct ipv6_devconf *all, *dflt;
6453 
6454 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6455 	if (!all)
6456 		goto err_alloc_all;
6457 
6458 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6459 	if (!dflt)
6460 		goto err_alloc_dflt;
6461 
6462 	/* these will be inherited by all namespaces */
6463 	dflt->autoconf = ipv6_defaults.autoconf;
6464 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6465 
6466 	dflt->stable_secret.initialized = false;
6467 	all->stable_secret.initialized = false;
6468 
6469 	net->ipv6.devconf_all = all;
6470 	net->ipv6.devconf_dflt = dflt;
6471 
6472 #ifdef CONFIG_SYSCTL
6473 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6474 	if (err < 0)
6475 		goto err_reg_all;
6476 
6477 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6478 	if (err < 0)
6479 		goto err_reg_dflt;
6480 #endif
6481 	return 0;
6482 
6483 #ifdef CONFIG_SYSCTL
6484 err_reg_dflt:
6485 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6486 err_reg_all:
6487 	kfree(dflt);
6488 #endif
6489 err_alloc_dflt:
6490 	kfree(all);
6491 err_alloc_all:
6492 	return err;
6493 }
6494 
6495 static void __net_exit addrconf_exit_net(struct net *net)
6496 {
6497 #ifdef CONFIG_SYSCTL
6498 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6499 				     NETCONFA_IFINDEX_DEFAULT);
6500 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6501 				     NETCONFA_IFINDEX_ALL);
6502 #endif
6503 	kfree(net->ipv6.devconf_dflt);
6504 	kfree(net->ipv6.devconf_all);
6505 }
6506 
6507 static struct pernet_operations addrconf_ops = {
6508 	.init = addrconf_init_net,
6509 	.exit = addrconf_exit_net,
6510 };
6511 
6512 static struct rtnl_af_ops inet6_ops __read_mostly = {
6513 	.family		  = AF_INET6,
6514 	.fill_link_af	  = inet6_fill_link_af,
6515 	.get_link_af_size = inet6_get_link_af_size,
6516 	.validate_link_af = inet6_validate_link_af,
6517 	.set_link_af	  = inet6_set_link_af,
6518 };
6519 
6520 /*
6521  *	Init / cleanup code
6522  */
6523 
6524 int __init addrconf_init(void)
6525 {
6526 	struct inet6_dev *idev;
6527 	int i, err;
6528 
6529 	err = ipv6_addr_label_init();
6530 	if (err < 0) {
6531 		pr_crit("%s: cannot initialize default policy table: %d\n",
6532 			__func__, err);
6533 		goto out;
6534 	}
6535 
6536 	err = register_pernet_subsys(&addrconf_ops);
6537 	if (err < 0)
6538 		goto out_addrlabel;
6539 
6540 	addrconf_wq = create_workqueue("ipv6_addrconf");
6541 	if (!addrconf_wq) {
6542 		err = -ENOMEM;
6543 		goto out_nowq;
6544 	}
6545 
6546 	/* The addrconf netdev notifier requires that loopback_dev
6547 	 * has it's ipv6 private information allocated and setup
6548 	 * before it can bring up and give link-local addresses
6549 	 * to other devices which are up.
6550 	 *
6551 	 * Unfortunately, loopback_dev is not necessarily the first
6552 	 * entry in the global dev_base list of net devices.  In fact,
6553 	 * it is likely to be the very last entry on that list.
6554 	 * So this causes the notifier registry below to try and
6555 	 * give link-local addresses to all devices besides loopback_dev
6556 	 * first, then loopback_dev, which cases all the non-loopback_dev
6557 	 * devices to fail to get a link-local address.
6558 	 *
6559 	 * So, as a temporary fix, allocate the ipv6 structure for
6560 	 * loopback_dev first by hand.
6561 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6562 	 * device and it being up should be removed.
6563 	 */
6564 	rtnl_lock();
6565 	idev = ipv6_add_dev(init_net.loopback_dev);
6566 	rtnl_unlock();
6567 	if (IS_ERR(idev)) {
6568 		err = PTR_ERR(idev);
6569 		goto errlo;
6570 	}
6571 
6572 	ip6_route_init_special_entries();
6573 
6574 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6575 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6576 
6577 	register_netdevice_notifier(&ipv6_dev_notf);
6578 
6579 	addrconf_verify();
6580 
6581 	rtnl_af_register(&inet6_ops);
6582 
6583 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6584 			      0);
6585 	if (err < 0)
6586 		goto errout;
6587 
6588 	/* Only the first call to __rtnl_register can fail */
6589 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, 0);
6590 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, 0);
6591 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6592 			inet6_dump_ifaddr, RTNL_FLAG_DOIT_UNLOCKED);
6593 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6594 			inet6_dump_ifmcaddr, 0);
6595 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6596 			inet6_dump_ifacaddr, 0);
6597 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6598 			inet6_netconf_dump_devconf, RTNL_FLAG_DOIT_UNLOCKED);
6599 
6600 	ipv6_addr_label_rtnl_register();
6601 
6602 	return 0;
6603 errout:
6604 	rtnl_af_unregister(&inet6_ops);
6605 	unregister_netdevice_notifier(&ipv6_dev_notf);
6606 errlo:
6607 	destroy_workqueue(addrconf_wq);
6608 out_nowq:
6609 	unregister_pernet_subsys(&addrconf_ops);
6610 out_addrlabel:
6611 	ipv6_addr_label_cleanup();
6612 out:
6613 	return err;
6614 }
6615 
6616 void addrconf_cleanup(void)
6617 {
6618 	struct net_device *dev;
6619 	int i;
6620 
6621 	unregister_netdevice_notifier(&ipv6_dev_notf);
6622 	unregister_pernet_subsys(&addrconf_ops);
6623 	ipv6_addr_label_cleanup();
6624 
6625 	rtnl_af_unregister(&inet6_ops);
6626 
6627 	rtnl_lock();
6628 
6629 	/* clean dev list */
6630 	for_each_netdev(&init_net, dev) {
6631 		if (__in6_dev_get(dev) == NULL)
6632 			continue;
6633 		addrconf_ifdown(dev, 1);
6634 	}
6635 	addrconf_ifdown(init_net.loopback_dev, 2);
6636 
6637 	/*
6638 	 *	Check hash table.
6639 	 */
6640 	spin_lock_bh(&addrconf_hash_lock);
6641 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6642 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6643 	spin_unlock_bh(&addrconf_hash_lock);
6644 	cancel_delayed_work(&addr_chk_work);
6645 	rtnl_unlock();
6646 
6647 	destroy_workqueue(addrconf_wq);
6648 }
6649