xref: /linux/net/ipv6/addrconf.c (revision de77b966ce8adcb4c58d50e2f087320d5479812a)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(fmt, ...) printk(fmt, ##__VA_ARGS__)
102 #else
103 #define ADBG(fmt, ...) do { if (0) printk(fmt, ##__VA_ARGS__); } while (0)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 #define IPV6_MAX_STRLEN \
109 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
110 
111 static inline u32 cstamp_delta(unsigned long cstamp)
112 {
113 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
114 }
115 
116 static inline s32 rfc3315_s14_backoff_init(s32 irt)
117 {
118 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
119 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
120 	do_div(tmp, 1000000);
121 	return (s32)tmp;
122 }
123 
124 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
125 {
126 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
127 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
128 	do_div(tmp, 1000000);
129 	if ((s32)tmp > mrt) {
130 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
131 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
132 		do_div(tmp, 1000000);
133 	}
134 	return (s32)tmp;
135 }
136 
137 #ifdef CONFIG_SYSCTL
138 static int addrconf_sysctl_register(struct inet6_dev *idev);
139 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
140 #else
141 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
142 {
143 	return 0;
144 }
145 
146 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
147 {
148 }
149 #endif
150 
151 static void ipv6_regen_rndid(struct inet6_dev *idev);
152 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
153 
154 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
155 static int ipv6_count_addresses(struct inet6_dev *idev);
156 static int ipv6_generate_stable_address(struct in6_addr *addr,
157 					u8 dad_count,
158 					const struct inet6_dev *idev);
159 
160 /*
161  *	Configured unicast address hash table
162  */
163 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
164 static DEFINE_SPINLOCK(addrconf_hash_lock);
165 
166 static void addrconf_verify(void);
167 static void addrconf_verify_rtnl(void);
168 static void addrconf_verify_work(struct work_struct *);
169 
170 static struct workqueue_struct *addrconf_wq;
171 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
172 
173 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
174 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
175 
176 static void addrconf_type_change(struct net_device *dev,
177 				 unsigned long event);
178 static int addrconf_ifdown(struct net_device *dev, int how);
179 
180 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
181 						  int plen,
182 						  const struct net_device *dev,
183 						  u32 flags, u32 noflags);
184 
185 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
186 static void addrconf_dad_work(struct work_struct *w);
187 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id);
188 static void addrconf_dad_run(struct inet6_dev *idev);
189 static void addrconf_rs_timer(unsigned long data);
190 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
191 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
192 
193 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
194 				struct prefix_info *pinfo);
195 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
196 			       struct net_device *dev);
197 
198 static struct ipv6_devconf ipv6_devconf __read_mostly = {
199 	.forwarding		= 0,
200 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
201 	.mtu6			= IPV6_MIN_MTU,
202 	.accept_ra		= 1,
203 	.accept_redirects	= 1,
204 	.autoconf		= 1,
205 	.force_mld_version	= 0,
206 	.mldv1_unsolicited_report_interval = 10 * HZ,
207 	.mldv2_unsolicited_report_interval = HZ,
208 	.dad_transmits		= 1,
209 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
210 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
211 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
212 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
213 	.use_tempaddr		= 0,
214 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
215 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
216 	.regen_max_retry	= REGEN_MAX_RETRY,
217 	.max_desync_factor	= MAX_DESYNC_FACTOR,
218 	.max_addresses		= IPV6_MAX_ADDRESSES,
219 	.accept_ra_defrtr	= 1,
220 	.accept_ra_from_local	= 0,
221 	.accept_ra_min_hop_limit= 1,
222 	.accept_ra_pinfo	= 1,
223 #ifdef CONFIG_IPV6_ROUTER_PREF
224 	.accept_ra_rtr_pref	= 1,
225 	.rtr_probe_interval	= 60 * HZ,
226 #ifdef CONFIG_IPV6_ROUTE_INFO
227 	.accept_ra_rt_info_min_plen = 0,
228 	.accept_ra_rt_info_max_plen = 0,
229 #endif
230 #endif
231 	.proxy_ndp		= 0,
232 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
233 	.disable_ipv6		= 0,
234 	.accept_dad		= 1,
235 	.suppress_frag_ndisc	= 1,
236 	.accept_ra_mtu		= 1,
237 	.stable_secret		= {
238 		.initialized = false,
239 	},
240 	.use_oif_addrs_only	= 0,
241 	.ignore_routes_with_linkdown = 0,
242 	.keep_addr_on_down	= 0,
243 	.seg6_enabled		= 0,
244 #ifdef CONFIG_IPV6_SEG6_HMAC
245 	.seg6_require_hmac	= 0,
246 #endif
247 	.enhanced_dad           = 1,
248 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
249 	.disable_policy		= 0,
250 };
251 
252 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
253 	.forwarding		= 0,
254 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
255 	.mtu6			= IPV6_MIN_MTU,
256 	.accept_ra		= 1,
257 	.accept_redirects	= 1,
258 	.autoconf		= 1,
259 	.force_mld_version	= 0,
260 	.mldv1_unsolicited_report_interval = 10 * HZ,
261 	.mldv2_unsolicited_report_interval = HZ,
262 	.dad_transmits		= 1,
263 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
264 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
265 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
266 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
267 	.use_tempaddr		= 0,
268 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
269 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
270 	.regen_max_retry	= REGEN_MAX_RETRY,
271 	.max_desync_factor	= MAX_DESYNC_FACTOR,
272 	.max_addresses		= IPV6_MAX_ADDRESSES,
273 	.accept_ra_defrtr	= 1,
274 	.accept_ra_from_local	= 0,
275 	.accept_ra_min_hop_limit= 1,
276 	.accept_ra_pinfo	= 1,
277 #ifdef CONFIG_IPV6_ROUTER_PREF
278 	.accept_ra_rtr_pref	= 1,
279 	.rtr_probe_interval	= 60 * HZ,
280 #ifdef CONFIG_IPV6_ROUTE_INFO
281 	.accept_ra_rt_info_min_plen = 0,
282 	.accept_ra_rt_info_max_plen = 0,
283 #endif
284 #endif
285 	.proxy_ndp		= 0,
286 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
287 	.disable_ipv6		= 0,
288 	.accept_dad		= 1,
289 	.suppress_frag_ndisc	= 1,
290 	.accept_ra_mtu		= 1,
291 	.stable_secret		= {
292 		.initialized = false,
293 	},
294 	.use_oif_addrs_only	= 0,
295 	.ignore_routes_with_linkdown = 0,
296 	.keep_addr_on_down	= 0,
297 	.seg6_enabled		= 0,
298 #ifdef CONFIG_IPV6_SEG6_HMAC
299 	.seg6_require_hmac	= 0,
300 #endif
301 	.enhanced_dad           = 1,
302 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
303 	.disable_policy		= 0,
304 };
305 
306 /* Check if a valid qdisc is available */
307 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
308 {
309 	return !qdisc_tx_is_noop(dev);
310 }
311 
312 static void addrconf_del_rs_timer(struct inet6_dev *idev)
313 {
314 	if (del_timer(&idev->rs_timer))
315 		__in6_dev_put(idev);
316 }
317 
318 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
319 {
320 	if (cancel_delayed_work(&ifp->dad_work))
321 		__in6_ifa_put(ifp);
322 }
323 
324 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
325 				  unsigned long when)
326 {
327 	if (!timer_pending(&idev->rs_timer))
328 		in6_dev_hold(idev);
329 	mod_timer(&idev->rs_timer, jiffies + when);
330 }
331 
332 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
333 				   unsigned long delay)
334 {
335 	if (!delayed_work_pending(&ifp->dad_work))
336 		in6_ifa_hold(ifp);
337 	mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
338 }
339 
340 static int snmp6_alloc_dev(struct inet6_dev *idev)
341 {
342 	int i;
343 
344 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
345 	if (!idev->stats.ipv6)
346 		goto err_ip;
347 
348 	for_each_possible_cpu(i) {
349 		struct ipstats_mib *addrconf_stats;
350 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
351 		u64_stats_init(&addrconf_stats->syncp);
352 	}
353 
354 
355 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
356 					GFP_KERNEL);
357 	if (!idev->stats.icmpv6dev)
358 		goto err_icmp;
359 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
360 					   GFP_KERNEL);
361 	if (!idev->stats.icmpv6msgdev)
362 		goto err_icmpmsg;
363 
364 	return 0;
365 
366 err_icmpmsg:
367 	kfree(idev->stats.icmpv6dev);
368 err_icmp:
369 	free_percpu(idev->stats.ipv6);
370 err_ip:
371 	return -ENOMEM;
372 }
373 
374 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
375 {
376 	struct inet6_dev *ndev;
377 	int err = -ENOMEM;
378 
379 	ASSERT_RTNL();
380 
381 	if (dev->mtu < IPV6_MIN_MTU)
382 		return ERR_PTR(-EINVAL);
383 
384 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
385 	if (!ndev)
386 		return ERR_PTR(err);
387 
388 	rwlock_init(&ndev->lock);
389 	ndev->dev = dev;
390 	INIT_LIST_HEAD(&ndev->addr_list);
391 	setup_timer(&ndev->rs_timer, addrconf_rs_timer,
392 		    (unsigned long)ndev);
393 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
394 
395 	if (ndev->cnf.stable_secret.initialized)
396 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
397 	else
398 		ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
399 
400 	ndev->cnf.mtu6 = dev->mtu;
401 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
402 	if (!ndev->nd_parms) {
403 		kfree(ndev);
404 		return ERR_PTR(err);
405 	}
406 	if (ndev->cnf.forwarding)
407 		dev_disable_lro(dev);
408 	/* We refer to the device */
409 	dev_hold(dev);
410 
411 	if (snmp6_alloc_dev(ndev) < 0) {
412 		ADBG(KERN_WARNING
413 			"%s: cannot allocate memory for statistics; dev=%s.\n",
414 			__func__, dev->name);
415 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
416 		dev_put(dev);
417 		kfree(ndev);
418 		return ERR_PTR(err);
419 	}
420 
421 	if (snmp6_register_dev(ndev) < 0) {
422 		ADBG(KERN_WARNING
423 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
424 			__func__, dev->name);
425 		goto err_release;
426 	}
427 
428 	/* One reference from device. */
429 	in6_dev_hold(ndev);
430 
431 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
432 		ndev->cnf.accept_dad = -1;
433 
434 #if IS_ENABLED(CONFIG_IPV6_SIT)
435 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
436 		pr_info("%s: Disabled Multicast RS\n", dev->name);
437 		ndev->cnf.rtr_solicits = 0;
438 	}
439 #endif
440 
441 	INIT_LIST_HEAD(&ndev->tempaddr_list);
442 	ndev->desync_factor = U32_MAX;
443 	if ((dev->flags&IFF_LOOPBACK) ||
444 	    dev->type == ARPHRD_TUNNEL ||
445 	    dev->type == ARPHRD_TUNNEL6 ||
446 	    dev->type == ARPHRD_SIT ||
447 	    dev->type == ARPHRD_NONE) {
448 		ndev->cnf.use_tempaddr = -1;
449 	} else
450 		ipv6_regen_rndid(ndev);
451 
452 	ndev->token = in6addr_any;
453 
454 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
455 		ndev->if_flags |= IF_READY;
456 
457 	ipv6_mc_init_dev(ndev);
458 	ndev->tstamp = jiffies;
459 	err = addrconf_sysctl_register(ndev);
460 	if (err) {
461 		ipv6_mc_destroy_dev(ndev);
462 		snmp6_unregister_dev(ndev);
463 		goto err_release;
464 	}
465 	/* protected by rtnl_lock */
466 	rcu_assign_pointer(dev->ip6_ptr, ndev);
467 
468 	/* Join interface-local all-node multicast group */
469 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
470 
471 	/* Join all-node multicast group */
472 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
473 
474 	/* Join all-router multicast group if forwarding is set */
475 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
476 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
477 
478 	return ndev;
479 
480 err_release:
481 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
482 	ndev->dead = 1;
483 	in6_dev_finish_destroy(ndev);
484 	return ERR_PTR(err);
485 }
486 
487 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
488 {
489 	struct inet6_dev *idev;
490 
491 	ASSERT_RTNL();
492 
493 	idev = __in6_dev_get(dev);
494 	if (!idev) {
495 		idev = ipv6_add_dev(dev);
496 		if (IS_ERR(idev))
497 			return NULL;
498 	}
499 
500 	if (dev->flags&IFF_UP)
501 		ipv6_mc_up(idev);
502 	return idev;
503 }
504 
505 static int inet6_netconf_msgsize_devconf(int type)
506 {
507 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
508 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
509 	bool all = false;
510 
511 	if (type == NETCONFA_ALL)
512 		all = true;
513 
514 	if (all || type == NETCONFA_FORWARDING)
515 		size += nla_total_size(4);
516 #ifdef CONFIG_IPV6_MROUTE
517 	if (all || type == NETCONFA_MC_FORWARDING)
518 		size += nla_total_size(4);
519 #endif
520 	if (all || type == NETCONFA_PROXY_NEIGH)
521 		size += nla_total_size(4);
522 
523 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
524 		size += nla_total_size(4);
525 
526 	return size;
527 }
528 
529 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
530 				      struct ipv6_devconf *devconf, u32 portid,
531 				      u32 seq, int event, unsigned int flags,
532 				      int type)
533 {
534 	struct nlmsghdr  *nlh;
535 	struct netconfmsg *ncm;
536 	bool all = false;
537 
538 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
539 			flags);
540 	if (!nlh)
541 		return -EMSGSIZE;
542 
543 	if (type == NETCONFA_ALL)
544 		all = true;
545 
546 	ncm = nlmsg_data(nlh);
547 	ncm->ncm_family = AF_INET6;
548 
549 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
550 		goto nla_put_failure;
551 
552 	if (!devconf)
553 		goto out;
554 
555 	if ((all || type == NETCONFA_FORWARDING) &&
556 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
557 		goto nla_put_failure;
558 #ifdef CONFIG_IPV6_MROUTE
559 	if ((all || type == NETCONFA_MC_FORWARDING) &&
560 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
561 			devconf->mc_forwarding) < 0)
562 		goto nla_put_failure;
563 #endif
564 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
565 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
566 		goto nla_put_failure;
567 
568 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
569 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
570 			devconf->ignore_routes_with_linkdown) < 0)
571 		goto nla_put_failure;
572 
573 out:
574 	nlmsg_end(skb, nlh);
575 	return 0;
576 
577 nla_put_failure:
578 	nlmsg_cancel(skb, nlh);
579 	return -EMSGSIZE;
580 }
581 
582 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
583 				  int ifindex, struct ipv6_devconf *devconf)
584 {
585 	struct sk_buff *skb;
586 	int err = -ENOBUFS;
587 
588 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
589 	if (!skb)
590 		goto errout;
591 
592 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
593 					 event, 0, type);
594 	if (err < 0) {
595 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
596 		WARN_ON(err == -EMSGSIZE);
597 		kfree_skb(skb);
598 		goto errout;
599 	}
600 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
601 	return;
602 errout:
603 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
604 }
605 
606 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
607 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
608 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
609 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
610 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
611 };
612 
613 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
614 				     struct nlmsghdr *nlh,
615 				     struct netlink_ext_ack *extack)
616 {
617 	struct net *net = sock_net(in_skb->sk);
618 	struct nlattr *tb[NETCONFA_MAX+1];
619 	struct netconfmsg *ncm;
620 	struct sk_buff *skb;
621 	struct ipv6_devconf *devconf;
622 	struct inet6_dev *in6_dev;
623 	struct net_device *dev;
624 	int ifindex;
625 	int err;
626 
627 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
628 			  devconf_ipv6_policy, extack);
629 	if (err < 0)
630 		goto errout;
631 
632 	err = -EINVAL;
633 	if (!tb[NETCONFA_IFINDEX])
634 		goto errout;
635 
636 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
637 	switch (ifindex) {
638 	case NETCONFA_IFINDEX_ALL:
639 		devconf = net->ipv6.devconf_all;
640 		break;
641 	case NETCONFA_IFINDEX_DEFAULT:
642 		devconf = net->ipv6.devconf_dflt;
643 		break;
644 	default:
645 		dev = __dev_get_by_index(net, ifindex);
646 		if (!dev)
647 			goto errout;
648 		in6_dev = __in6_dev_get(dev);
649 		if (!in6_dev)
650 			goto errout;
651 		devconf = &in6_dev->cnf;
652 		break;
653 	}
654 
655 	err = -ENOBUFS;
656 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_ATOMIC);
657 	if (!skb)
658 		goto errout;
659 
660 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
661 					 NETLINK_CB(in_skb).portid,
662 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
663 					 NETCONFA_ALL);
664 	if (err < 0) {
665 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
666 		WARN_ON(err == -EMSGSIZE);
667 		kfree_skb(skb);
668 		goto errout;
669 	}
670 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
671 errout:
672 	return err;
673 }
674 
675 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
676 				      struct netlink_callback *cb)
677 {
678 	struct net *net = sock_net(skb->sk);
679 	int h, s_h;
680 	int idx, s_idx;
681 	struct net_device *dev;
682 	struct inet6_dev *idev;
683 	struct hlist_head *head;
684 
685 	s_h = cb->args[0];
686 	s_idx = idx = cb->args[1];
687 
688 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
689 		idx = 0;
690 		head = &net->dev_index_head[h];
691 		rcu_read_lock();
692 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
693 			  net->dev_base_seq;
694 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
695 			if (idx < s_idx)
696 				goto cont;
697 			idev = __in6_dev_get(dev);
698 			if (!idev)
699 				goto cont;
700 
701 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
702 						       &idev->cnf,
703 						       NETLINK_CB(cb->skb).portid,
704 						       cb->nlh->nlmsg_seq,
705 						       RTM_NEWNETCONF,
706 						       NLM_F_MULTI,
707 						       NETCONFA_ALL) < 0) {
708 				rcu_read_unlock();
709 				goto done;
710 			}
711 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
712 cont:
713 			idx++;
714 		}
715 		rcu_read_unlock();
716 	}
717 	if (h == NETDEV_HASHENTRIES) {
718 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
719 					       net->ipv6.devconf_all,
720 					       NETLINK_CB(cb->skb).portid,
721 					       cb->nlh->nlmsg_seq,
722 					       RTM_NEWNETCONF, NLM_F_MULTI,
723 					       NETCONFA_ALL) < 0)
724 			goto done;
725 		else
726 			h++;
727 	}
728 	if (h == NETDEV_HASHENTRIES + 1) {
729 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
730 					       net->ipv6.devconf_dflt,
731 					       NETLINK_CB(cb->skb).portid,
732 					       cb->nlh->nlmsg_seq,
733 					       RTM_NEWNETCONF, NLM_F_MULTI,
734 					       NETCONFA_ALL) < 0)
735 			goto done;
736 		else
737 			h++;
738 	}
739 done:
740 	cb->args[0] = h;
741 	cb->args[1] = idx;
742 
743 	return skb->len;
744 }
745 
746 #ifdef CONFIG_SYSCTL
747 static void dev_forward_change(struct inet6_dev *idev)
748 {
749 	struct net_device *dev;
750 	struct inet6_ifaddr *ifa;
751 
752 	if (!idev)
753 		return;
754 	dev = idev->dev;
755 	if (idev->cnf.forwarding)
756 		dev_disable_lro(dev);
757 	if (dev->flags & IFF_MULTICAST) {
758 		if (idev->cnf.forwarding) {
759 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
760 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
761 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
762 		} else {
763 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
764 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
765 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
766 		}
767 	}
768 
769 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
770 		if (ifa->flags&IFA_F_TENTATIVE)
771 			continue;
772 		if (idev->cnf.forwarding)
773 			addrconf_join_anycast(ifa);
774 		else
775 			addrconf_leave_anycast(ifa);
776 	}
777 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
778 				     NETCONFA_FORWARDING,
779 				     dev->ifindex, &idev->cnf);
780 }
781 
782 
783 static void addrconf_forward_change(struct net *net, __s32 newf)
784 {
785 	struct net_device *dev;
786 	struct inet6_dev *idev;
787 
788 	for_each_netdev(net, dev) {
789 		idev = __in6_dev_get(dev);
790 		if (idev) {
791 			int changed = (!idev->cnf.forwarding) ^ (!newf);
792 			idev->cnf.forwarding = newf;
793 			if (changed)
794 				dev_forward_change(idev);
795 		}
796 	}
797 }
798 
799 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
800 {
801 	struct net *net;
802 	int old;
803 
804 	if (!rtnl_trylock())
805 		return restart_syscall();
806 
807 	net = (struct net *)table->extra2;
808 	old = *p;
809 	*p = newf;
810 
811 	if (p == &net->ipv6.devconf_dflt->forwarding) {
812 		if ((!newf) ^ (!old))
813 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
814 						     NETCONFA_FORWARDING,
815 						     NETCONFA_IFINDEX_DEFAULT,
816 						     net->ipv6.devconf_dflt);
817 		rtnl_unlock();
818 		return 0;
819 	}
820 
821 	if (p == &net->ipv6.devconf_all->forwarding) {
822 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
823 
824 		net->ipv6.devconf_dflt->forwarding = newf;
825 		if ((!newf) ^ (!old_dflt))
826 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
827 						     NETCONFA_FORWARDING,
828 						     NETCONFA_IFINDEX_DEFAULT,
829 						     net->ipv6.devconf_dflt);
830 
831 		addrconf_forward_change(net, newf);
832 		if ((!newf) ^ (!old))
833 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
834 						     NETCONFA_FORWARDING,
835 						     NETCONFA_IFINDEX_ALL,
836 						     net->ipv6.devconf_all);
837 	} else if ((!newf) ^ (!old))
838 		dev_forward_change((struct inet6_dev *)table->extra1);
839 	rtnl_unlock();
840 
841 	if (newf)
842 		rt6_purge_dflt_routers(net);
843 	return 1;
844 }
845 
846 static void addrconf_linkdown_change(struct net *net, __s32 newf)
847 {
848 	struct net_device *dev;
849 	struct inet6_dev *idev;
850 
851 	for_each_netdev(net, dev) {
852 		idev = __in6_dev_get(dev);
853 		if (idev) {
854 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
855 
856 			idev->cnf.ignore_routes_with_linkdown = newf;
857 			if (changed)
858 				inet6_netconf_notify_devconf(dev_net(dev),
859 							     RTM_NEWNETCONF,
860 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
861 							     dev->ifindex,
862 							     &idev->cnf);
863 		}
864 	}
865 }
866 
867 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
868 {
869 	struct net *net;
870 	int old;
871 
872 	if (!rtnl_trylock())
873 		return restart_syscall();
874 
875 	net = (struct net *)table->extra2;
876 	old = *p;
877 	*p = newf;
878 
879 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
880 		if ((!newf) ^ (!old))
881 			inet6_netconf_notify_devconf(net,
882 						     RTM_NEWNETCONF,
883 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
884 						     NETCONFA_IFINDEX_DEFAULT,
885 						     net->ipv6.devconf_dflt);
886 		rtnl_unlock();
887 		return 0;
888 	}
889 
890 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
891 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
892 		addrconf_linkdown_change(net, newf);
893 		if ((!newf) ^ (!old))
894 			inet6_netconf_notify_devconf(net,
895 						     RTM_NEWNETCONF,
896 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
897 						     NETCONFA_IFINDEX_ALL,
898 						     net->ipv6.devconf_all);
899 	}
900 	rtnl_unlock();
901 
902 	return 1;
903 }
904 
905 #endif
906 
907 /* Nobody refers to this ifaddr, destroy it */
908 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
909 {
910 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
911 
912 #ifdef NET_REFCNT_DEBUG
913 	pr_debug("%s\n", __func__);
914 #endif
915 
916 	in6_dev_put(ifp->idev);
917 
918 	if (cancel_delayed_work(&ifp->dad_work))
919 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
920 			  ifp);
921 
922 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
923 		pr_warn("Freeing alive inet6 address %p\n", ifp);
924 		return;
925 	}
926 	ip6_rt_put(ifp->rt);
927 
928 	kfree_rcu(ifp, rcu);
929 }
930 
931 static void
932 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
933 {
934 	struct list_head *p;
935 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
936 
937 	/*
938 	 * Each device address list is sorted in order of scope -
939 	 * global before linklocal.
940 	 */
941 	list_for_each(p, &idev->addr_list) {
942 		struct inet6_ifaddr *ifa
943 			= list_entry(p, struct inet6_ifaddr, if_list);
944 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
945 			break;
946 	}
947 
948 	list_add_tail(&ifp->if_list, p);
949 }
950 
951 static u32 inet6_addr_hash(const struct in6_addr *addr)
952 {
953 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
954 }
955 
956 /* On success it returns ifp with increased reference count */
957 
958 static struct inet6_ifaddr *
959 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
960 	      const struct in6_addr *peer_addr, int pfxlen,
961 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft)
962 {
963 	struct net *net = dev_net(idev->dev);
964 	struct inet6_ifaddr *ifa = NULL;
965 	struct rt6_info *rt;
966 	struct in6_validator_info i6vi;
967 	unsigned int hash;
968 	int err = 0;
969 	int addr_type = ipv6_addr_type(addr);
970 
971 	if (addr_type == IPV6_ADDR_ANY ||
972 	    addr_type & IPV6_ADDR_MULTICAST ||
973 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
974 	     addr_type & IPV6_ADDR_LOOPBACK))
975 		return ERR_PTR(-EADDRNOTAVAIL);
976 
977 	rcu_read_lock_bh();
978 
979 	in6_dev_hold(idev);
980 
981 	if (idev->dead) {
982 		err = -ENODEV;			/*XXX*/
983 		goto out2;
984 	}
985 
986 	if (idev->cnf.disable_ipv6) {
987 		err = -EACCES;
988 		goto out2;
989 	}
990 
991 	i6vi.i6vi_addr = *addr;
992 	i6vi.i6vi_dev = idev;
993 	rcu_read_unlock_bh();
994 
995 	err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
996 
997 	rcu_read_lock_bh();
998 	err = notifier_to_errno(err);
999 	if (err)
1000 		goto out2;
1001 
1002 	spin_lock(&addrconf_hash_lock);
1003 
1004 	/* Ignore adding duplicate addresses on an interface */
1005 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
1006 		ADBG("ipv6_add_addr: already assigned\n");
1007 		err = -EEXIST;
1008 		goto out;
1009 	}
1010 
1011 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
1012 
1013 	if (!ifa) {
1014 		ADBG("ipv6_add_addr: malloc failed\n");
1015 		err = -ENOBUFS;
1016 		goto out;
1017 	}
1018 
1019 	rt = addrconf_dst_alloc(idev, addr, false);
1020 	if (IS_ERR(rt)) {
1021 		err = PTR_ERR(rt);
1022 		goto out;
1023 	}
1024 
1025 	if (net->ipv6.devconf_all->disable_policy ||
1026 	    idev->cnf.disable_policy)
1027 		rt->dst.flags |= DST_NOPOLICY;
1028 
1029 	neigh_parms_data_state_setall(idev->nd_parms);
1030 
1031 	ifa->addr = *addr;
1032 	if (peer_addr)
1033 		ifa->peer_addr = *peer_addr;
1034 
1035 	spin_lock_init(&ifa->lock);
1036 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1037 	INIT_HLIST_NODE(&ifa->addr_lst);
1038 	ifa->scope = scope;
1039 	ifa->prefix_len = pfxlen;
1040 	ifa->flags = flags;
1041 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1042 	if (!(flags & IFA_F_NODAD))
1043 		ifa->flags |= IFA_F_TENTATIVE;
1044 	ifa->valid_lft = valid_lft;
1045 	ifa->prefered_lft = prefered_lft;
1046 	ifa->cstamp = ifa->tstamp = jiffies;
1047 	ifa->tokenized = false;
1048 
1049 	ifa->rt = rt;
1050 
1051 	ifa->idev = idev;
1052 	/* For caller */
1053 	in6_ifa_hold(ifa);
1054 
1055 	/* Add to big hash table */
1056 	hash = inet6_addr_hash(addr);
1057 
1058 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1059 	spin_unlock(&addrconf_hash_lock);
1060 
1061 	write_lock(&idev->lock);
1062 	/* Add to inet6_dev unicast addr list. */
1063 	ipv6_link_dev_addr(idev, ifa);
1064 
1065 	if (ifa->flags&IFA_F_TEMPORARY) {
1066 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1067 		in6_ifa_hold(ifa);
1068 	}
1069 
1070 	in6_ifa_hold(ifa);
1071 	write_unlock(&idev->lock);
1072 out2:
1073 	rcu_read_unlock_bh();
1074 
1075 	if (likely(err == 0))
1076 		inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1077 	else {
1078 		kfree(ifa);
1079 		in6_dev_put(idev);
1080 		ifa = ERR_PTR(err);
1081 	}
1082 
1083 	return ifa;
1084 out:
1085 	spin_unlock(&addrconf_hash_lock);
1086 	goto out2;
1087 }
1088 
1089 enum cleanup_prefix_rt_t {
1090 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1091 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1092 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1093 };
1094 
1095 /*
1096  * Check, whether the prefix for ifp would still need a prefix route
1097  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1098  * constants.
1099  *
1100  * 1) we don't purge prefix if address was not permanent.
1101  *    prefix is managed by its own lifetime.
1102  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1103  * 3) if there are no addresses, delete prefix.
1104  * 4) if there are still other permanent address(es),
1105  *    corresponding prefix is still permanent.
1106  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1107  *    don't purge the prefix, assume user space is managing it.
1108  * 6) otherwise, update prefix lifetime to the
1109  *    longest valid lifetime among the corresponding
1110  *    addresses on the device.
1111  *    Note: subsequent RA will update lifetime.
1112  **/
1113 static enum cleanup_prefix_rt_t
1114 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1115 {
1116 	struct inet6_ifaddr *ifa;
1117 	struct inet6_dev *idev = ifp->idev;
1118 	unsigned long lifetime;
1119 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1120 
1121 	*expires = jiffies;
1122 
1123 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1124 		if (ifa == ifp)
1125 			continue;
1126 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1127 				       ifp->prefix_len))
1128 			continue;
1129 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1130 			return CLEANUP_PREFIX_RT_NOP;
1131 
1132 		action = CLEANUP_PREFIX_RT_EXPIRE;
1133 
1134 		spin_lock(&ifa->lock);
1135 
1136 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1137 		/*
1138 		 * Note: Because this address is
1139 		 * not permanent, lifetime <
1140 		 * LONG_MAX / HZ here.
1141 		 */
1142 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1143 			*expires = ifa->tstamp + lifetime * HZ;
1144 		spin_unlock(&ifa->lock);
1145 	}
1146 
1147 	return action;
1148 }
1149 
1150 static void
1151 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1152 {
1153 	struct rt6_info *rt;
1154 
1155 	rt = addrconf_get_prefix_route(&ifp->addr,
1156 				       ifp->prefix_len,
1157 				       ifp->idev->dev,
1158 				       0, RTF_GATEWAY | RTF_DEFAULT);
1159 	if (rt) {
1160 		if (del_rt)
1161 			ip6_del_rt(rt);
1162 		else {
1163 			if (!(rt->rt6i_flags & RTF_EXPIRES))
1164 				rt6_set_expires(rt, expires);
1165 			ip6_rt_put(rt);
1166 		}
1167 	}
1168 }
1169 
1170 
1171 /* This function wants to get referenced ifp and releases it before return */
1172 
1173 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1174 {
1175 	int state;
1176 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1177 	unsigned long expires;
1178 
1179 	ASSERT_RTNL();
1180 
1181 	spin_lock_bh(&ifp->lock);
1182 	state = ifp->state;
1183 	ifp->state = INET6_IFADDR_STATE_DEAD;
1184 	spin_unlock_bh(&ifp->lock);
1185 
1186 	if (state == INET6_IFADDR_STATE_DEAD)
1187 		goto out;
1188 
1189 	spin_lock_bh(&addrconf_hash_lock);
1190 	hlist_del_init_rcu(&ifp->addr_lst);
1191 	spin_unlock_bh(&addrconf_hash_lock);
1192 
1193 	write_lock_bh(&ifp->idev->lock);
1194 
1195 	if (ifp->flags&IFA_F_TEMPORARY) {
1196 		list_del(&ifp->tmp_list);
1197 		if (ifp->ifpub) {
1198 			in6_ifa_put(ifp->ifpub);
1199 			ifp->ifpub = NULL;
1200 		}
1201 		__in6_ifa_put(ifp);
1202 	}
1203 
1204 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1205 		action = check_cleanup_prefix_route(ifp, &expires);
1206 
1207 	list_del_init(&ifp->if_list);
1208 	__in6_ifa_put(ifp);
1209 
1210 	write_unlock_bh(&ifp->idev->lock);
1211 
1212 	addrconf_del_dad_work(ifp);
1213 
1214 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1215 
1216 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1217 
1218 	if (action != CLEANUP_PREFIX_RT_NOP) {
1219 		cleanup_prefix_route(ifp, expires,
1220 			action == CLEANUP_PREFIX_RT_DEL);
1221 	}
1222 
1223 	/* clean up prefsrc entries */
1224 	rt6_remove_prefsrc(ifp);
1225 out:
1226 	in6_ifa_put(ifp);
1227 }
1228 
1229 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
1230 {
1231 	struct inet6_dev *idev = ifp->idev;
1232 	struct in6_addr addr, *tmpaddr;
1233 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1234 	unsigned long regen_advance;
1235 	int tmp_plen;
1236 	int ret = 0;
1237 	u32 addr_flags;
1238 	unsigned long now = jiffies;
1239 	long max_desync_factor;
1240 	s32 cnf_temp_preferred_lft;
1241 
1242 	write_lock_bh(&idev->lock);
1243 	if (ift) {
1244 		spin_lock_bh(&ift->lock);
1245 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1246 		spin_unlock_bh(&ift->lock);
1247 		tmpaddr = &addr;
1248 	} else {
1249 		tmpaddr = NULL;
1250 	}
1251 retry:
1252 	in6_dev_hold(idev);
1253 	if (idev->cnf.use_tempaddr <= 0) {
1254 		write_unlock_bh(&idev->lock);
1255 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1256 		in6_dev_put(idev);
1257 		ret = -1;
1258 		goto out;
1259 	}
1260 	spin_lock_bh(&ifp->lock);
1261 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1262 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1263 		spin_unlock_bh(&ifp->lock);
1264 		write_unlock_bh(&idev->lock);
1265 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1266 			__func__);
1267 		in6_dev_put(idev);
1268 		ret = -1;
1269 		goto out;
1270 	}
1271 	in6_ifa_hold(ifp);
1272 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1273 	ipv6_try_regen_rndid(idev, tmpaddr);
1274 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1275 	age = (now - ifp->tstamp) / HZ;
1276 
1277 	regen_advance = idev->cnf.regen_max_retry *
1278 			idev->cnf.dad_transmits *
1279 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1280 
1281 	/* recalculate max_desync_factor each time and update
1282 	 * idev->desync_factor if it's larger
1283 	 */
1284 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1285 	max_desync_factor = min_t(__u32,
1286 				  idev->cnf.max_desync_factor,
1287 				  cnf_temp_preferred_lft - regen_advance);
1288 
1289 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1290 		if (max_desync_factor > 0) {
1291 			get_random_bytes(&idev->desync_factor,
1292 					 sizeof(idev->desync_factor));
1293 			idev->desync_factor %= max_desync_factor;
1294 		} else {
1295 			idev->desync_factor = 0;
1296 		}
1297 	}
1298 
1299 	tmp_valid_lft = min_t(__u32,
1300 			      ifp->valid_lft,
1301 			      idev->cnf.temp_valid_lft + age);
1302 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1303 			    idev->desync_factor;
1304 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1305 	tmp_plen = ifp->prefix_len;
1306 	tmp_tstamp = ifp->tstamp;
1307 	spin_unlock_bh(&ifp->lock);
1308 
1309 	write_unlock_bh(&idev->lock);
1310 
1311 	/* A temporary address is created only if this calculated Preferred
1312 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1313 	 * an implementation must not create a temporary address with a zero
1314 	 * Preferred Lifetime.
1315 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1316 	 * temporary addresses being generated.
1317 	 */
1318 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1319 	if (tmp_prefered_lft <= regen_advance + age) {
1320 		in6_ifa_put(ifp);
1321 		in6_dev_put(idev);
1322 		ret = -1;
1323 		goto out;
1324 	}
1325 
1326 	addr_flags = IFA_F_TEMPORARY;
1327 	/* set in addrconf_prefix_rcv() */
1328 	if (ifp->flags & IFA_F_OPTIMISTIC)
1329 		addr_flags |= IFA_F_OPTIMISTIC;
1330 
1331 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1332 			    ipv6_addr_scope(&addr), addr_flags,
1333 			    tmp_valid_lft, tmp_prefered_lft);
1334 	if (IS_ERR(ift)) {
1335 		in6_ifa_put(ifp);
1336 		in6_dev_put(idev);
1337 		pr_info("%s: retry temporary address regeneration\n", __func__);
1338 		tmpaddr = &addr;
1339 		write_lock_bh(&idev->lock);
1340 		goto retry;
1341 	}
1342 
1343 	spin_lock_bh(&ift->lock);
1344 	ift->ifpub = ifp;
1345 	ift->cstamp = now;
1346 	ift->tstamp = tmp_tstamp;
1347 	spin_unlock_bh(&ift->lock);
1348 
1349 	addrconf_dad_start(ift);
1350 	in6_ifa_put(ift);
1351 	in6_dev_put(idev);
1352 out:
1353 	return ret;
1354 }
1355 
1356 /*
1357  *	Choose an appropriate source address (RFC3484)
1358  */
1359 enum {
1360 	IPV6_SADDR_RULE_INIT = 0,
1361 	IPV6_SADDR_RULE_LOCAL,
1362 	IPV6_SADDR_RULE_SCOPE,
1363 	IPV6_SADDR_RULE_PREFERRED,
1364 #ifdef CONFIG_IPV6_MIP6
1365 	IPV6_SADDR_RULE_HOA,
1366 #endif
1367 	IPV6_SADDR_RULE_OIF,
1368 	IPV6_SADDR_RULE_LABEL,
1369 	IPV6_SADDR_RULE_PRIVACY,
1370 	IPV6_SADDR_RULE_ORCHID,
1371 	IPV6_SADDR_RULE_PREFIX,
1372 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1373 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1374 #endif
1375 	IPV6_SADDR_RULE_MAX
1376 };
1377 
1378 struct ipv6_saddr_score {
1379 	int			rule;
1380 	int			addr_type;
1381 	struct inet6_ifaddr	*ifa;
1382 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1383 	int			scopedist;
1384 	int			matchlen;
1385 };
1386 
1387 struct ipv6_saddr_dst {
1388 	const struct in6_addr *addr;
1389 	int ifindex;
1390 	int scope;
1391 	int label;
1392 	unsigned int prefs;
1393 };
1394 
1395 static inline int ipv6_saddr_preferred(int type)
1396 {
1397 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1398 		return 1;
1399 	return 0;
1400 }
1401 
1402 static inline bool ipv6_use_optimistic_addr(struct inet6_dev *idev)
1403 {
1404 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1405 	return idev && idev->cnf.optimistic_dad && idev->cnf.use_optimistic;
1406 #else
1407 	return false;
1408 #endif
1409 }
1410 
1411 static int ipv6_get_saddr_eval(struct net *net,
1412 			       struct ipv6_saddr_score *score,
1413 			       struct ipv6_saddr_dst *dst,
1414 			       int i)
1415 {
1416 	int ret;
1417 
1418 	if (i <= score->rule) {
1419 		switch (i) {
1420 		case IPV6_SADDR_RULE_SCOPE:
1421 			ret = score->scopedist;
1422 			break;
1423 		case IPV6_SADDR_RULE_PREFIX:
1424 			ret = score->matchlen;
1425 			break;
1426 		default:
1427 			ret = !!test_bit(i, score->scorebits);
1428 		}
1429 		goto out;
1430 	}
1431 
1432 	switch (i) {
1433 	case IPV6_SADDR_RULE_INIT:
1434 		/* Rule 0: remember if hiscore is not ready yet */
1435 		ret = !!score->ifa;
1436 		break;
1437 	case IPV6_SADDR_RULE_LOCAL:
1438 		/* Rule 1: Prefer same address */
1439 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1440 		break;
1441 	case IPV6_SADDR_RULE_SCOPE:
1442 		/* Rule 2: Prefer appropriate scope
1443 		 *
1444 		 *      ret
1445 		 *       ^
1446 		 *    -1 |  d 15
1447 		 *    ---+--+-+---> scope
1448 		 *       |
1449 		 *       |             d is scope of the destination.
1450 		 *  B-d  |  \
1451 		 *       |   \      <- smaller scope is better if
1452 		 *  B-15 |    \        if scope is enough for destination.
1453 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1454 		 * d-C-1 | /
1455 		 *       |/         <- greater is better
1456 		 *   -C  /             if scope is not enough for destination.
1457 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1458 		 *
1459 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1460 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1461 		 * Assume B = 0 and we get C > 29.
1462 		 */
1463 		ret = __ipv6_addr_src_scope(score->addr_type);
1464 		if (ret >= dst->scope)
1465 			ret = -ret;
1466 		else
1467 			ret -= 128;	/* 30 is enough */
1468 		score->scopedist = ret;
1469 		break;
1470 	case IPV6_SADDR_RULE_PREFERRED:
1471 	    {
1472 		/* Rule 3: Avoid deprecated and optimistic addresses */
1473 		u8 avoid = IFA_F_DEPRECATED;
1474 
1475 		if (!ipv6_use_optimistic_addr(score->ifa->idev))
1476 			avoid |= IFA_F_OPTIMISTIC;
1477 		ret = ipv6_saddr_preferred(score->addr_type) ||
1478 		      !(score->ifa->flags & avoid);
1479 		break;
1480 	    }
1481 #ifdef CONFIG_IPV6_MIP6
1482 	case IPV6_SADDR_RULE_HOA:
1483 	    {
1484 		/* Rule 4: Prefer home address */
1485 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1486 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1487 		break;
1488 	    }
1489 #endif
1490 	case IPV6_SADDR_RULE_OIF:
1491 		/* Rule 5: Prefer outgoing interface */
1492 		ret = (!dst->ifindex ||
1493 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1494 		break;
1495 	case IPV6_SADDR_RULE_LABEL:
1496 		/* Rule 6: Prefer matching label */
1497 		ret = ipv6_addr_label(net,
1498 				      &score->ifa->addr, score->addr_type,
1499 				      score->ifa->idev->dev->ifindex) == dst->label;
1500 		break;
1501 	case IPV6_SADDR_RULE_PRIVACY:
1502 	    {
1503 		/* Rule 7: Prefer public address
1504 		 * Note: prefer temporary address if use_tempaddr >= 2
1505 		 */
1506 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1507 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1508 				score->ifa->idev->cnf.use_tempaddr >= 2;
1509 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1510 		break;
1511 	    }
1512 	case IPV6_SADDR_RULE_ORCHID:
1513 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1514 		 *	    non-ORCHID vs non-ORCHID
1515 		 */
1516 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1517 			ipv6_addr_orchid(dst->addr));
1518 		break;
1519 	case IPV6_SADDR_RULE_PREFIX:
1520 		/* Rule 8: Use longest matching prefix */
1521 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1522 		if (ret > score->ifa->prefix_len)
1523 			ret = score->ifa->prefix_len;
1524 		score->matchlen = ret;
1525 		break;
1526 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1527 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1528 		/* Optimistic addresses still have lower precedence than other
1529 		 * preferred addresses.
1530 		 */
1531 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1532 		break;
1533 #endif
1534 	default:
1535 		ret = 0;
1536 	}
1537 
1538 	if (ret)
1539 		__set_bit(i, score->scorebits);
1540 	score->rule = i;
1541 out:
1542 	return ret;
1543 }
1544 
1545 static int __ipv6_dev_get_saddr(struct net *net,
1546 				struct ipv6_saddr_dst *dst,
1547 				struct inet6_dev *idev,
1548 				struct ipv6_saddr_score *scores,
1549 				int hiscore_idx)
1550 {
1551 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1552 
1553 	read_lock_bh(&idev->lock);
1554 	list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1555 		int i;
1556 
1557 		/*
1558 		 * - Tentative Address (RFC2462 section 5.4)
1559 		 *  - A tentative address is not considered
1560 		 *    "assigned to an interface" in the traditional
1561 		 *    sense, unless it is also flagged as optimistic.
1562 		 * - Candidate Source Address (section 4)
1563 		 *  - In any case, anycast addresses, multicast
1564 		 *    addresses, and the unspecified address MUST
1565 		 *    NOT be included in a candidate set.
1566 		 */
1567 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1568 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1569 			continue;
1570 
1571 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1572 
1573 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1574 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1575 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1576 					    idev->dev->name);
1577 			continue;
1578 		}
1579 
1580 		score->rule = -1;
1581 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1582 
1583 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1584 			int minihiscore, miniscore;
1585 
1586 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1587 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1588 
1589 			if (minihiscore > miniscore) {
1590 				if (i == IPV6_SADDR_RULE_SCOPE &&
1591 				    score->scopedist > 0) {
1592 					/*
1593 					 * special case:
1594 					 * each remaining entry
1595 					 * has too small (not enough)
1596 					 * scope, because ifa entries
1597 					 * are sorted by their scope
1598 					 * values.
1599 					 */
1600 					goto out;
1601 				}
1602 				break;
1603 			} else if (minihiscore < miniscore) {
1604 				if (hiscore->ifa)
1605 					in6_ifa_put(hiscore->ifa);
1606 
1607 				in6_ifa_hold(score->ifa);
1608 
1609 				swap(hiscore, score);
1610 				hiscore_idx = 1 - hiscore_idx;
1611 
1612 				/* restore our iterator */
1613 				score->ifa = hiscore->ifa;
1614 
1615 				break;
1616 			}
1617 		}
1618 	}
1619 out:
1620 	read_unlock_bh(&idev->lock);
1621 	return hiscore_idx;
1622 }
1623 
1624 static int ipv6_get_saddr_master(struct net *net,
1625 				 const struct net_device *dst_dev,
1626 				 const struct net_device *master,
1627 				 struct ipv6_saddr_dst *dst,
1628 				 struct ipv6_saddr_score *scores,
1629 				 int hiscore_idx)
1630 {
1631 	struct inet6_dev *idev;
1632 
1633 	idev = __in6_dev_get(dst_dev);
1634 	if (idev)
1635 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1636 						   scores, hiscore_idx);
1637 
1638 	idev = __in6_dev_get(master);
1639 	if (idev)
1640 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1641 						   scores, hiscore_idx);
1642 
1643 	return hiscore_idx;
1644 }
1645 
1646 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1647 		       const struct in6_addr *daddr, unsigned int prefs,
1648 		       struct in6_addr *saddr)
1649 {
1650 	struct ipv6_saddr_score scores[2], *hiscore;
1651 	struct ipv6_saddr_dst dst;
1652 	struct inet6_dev *idev;
1653 	struct net_device *dev;
1654 	int dst_type;
1655 	bool use_oif_addr = false;
1656 	int hiscore_idx = 0;
1657 
1658 	dst_type = __ipv6_addr_type(daddr);
1659 	dst.addr = daddr;
1660 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1661 	dst.scope = __ipv6_addr_src_scope(dst_type);
1662 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1663 	dst.prefs = prefs;
1664 
1665 	scores[hiscore_idx].rule = -1;
1666 	scores[hiscore_idx].ifa = NULL;
1667 
1668 	rcu_read_lock();
1669 
1670 	/* Candidate Source Address (section 4)
1671 	 *  - multicast and link-local destination address,
1672 	 *    the set of candidate source address MUST only
1673 	 *    include addresses assigned to interfaces
1674 	 *    belonging to the same link as the outgoing
1675 	 *    interface.
1676 	 * (- For site-local destination addresses, the
1677 	 *    set of candidate source addresses MUST only
1678 	 *    include addresses assigned to interfaces
1679 	 *    belonging to the same site as the outgoing
1680 	 *    interface.)
1681 	 *  - "It is RECOMMENDED that the candidate source addresses
1682 	 *    be the set of unicast addresses assigned to the
1683 	 *    interface that will be used to send to the destination
1684 	 *    (the 'outgoing' interface)." (RFC 6724)
1685 	 */
1686 	if (dst_dev) {
1687 		idev = __in6_dev_get(dst_dev);
1688 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1689 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1690 		    (idev && idev->cnf.use_oif_addrs_only)) {
1691 			use_oif_addr = true;
1692 		}
1693 	}
1694 
1695 	if (use_oif_addr) {
1696 		if (idev)
1697 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1698 	} else {
1699 		const struct net_device *master;
1700 		int master_idx = 0;
1701 
1702 		/* if dst_dev exists and is enslaved to an L3 device, then
1703 		 * prefer addresses from dst_dev and then the master over
1704 		 * any other enslaved devices in the L3 domain.
1705 		 */
1706 		master = l3mdev_master_dev_rcu(dst_dev);
1707 		if (master) {
1708 			master_idx = master->ifindex;
1709 
1710 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1711 							    master, &dst,
1712 							    scores, hiscore_idx);
1713 
1714 			if (scores[hiscore_idx].ifa)
1715 				goto out;
1716 		}
1717 
1718 		for_each_netdev_rcu(net, dev) {
1719 			/* only consider addresses on devices in the
1720 			 * same L3 domain
1721 			 */
1722 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1723 				continue;
1724 			idev = __in6_dev_get(dev);
1725 			if (!idev)
1726 				continue;
1727 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1728 		}
1729 	}
1730 
1731 out:
1732 	rcu_read_unlock();
1733 
1734 	hiscore = &scores[hiscore_idx];
1735 	if (!hiscore->ifa)
1736 		return -EADDRNOTAVAIL;
1737 
1738 	*saddr = hiscore->ifa->addr;
1739 	in6_ifa_put(hiscore->ifa);
1740 	return 0;
1741 }
1742 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1743 
1744 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1745 		      u32 banned_flags)
1746 {
1747 	struct inet6_ifaddr *ifp;
1748 	int err = -EADDRNOTAVAIL;
1749 
1750 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1751 		if (ifp->scope > IFA_LINK)
1752 			break;
1753 		if (ifp->scope == IFA_LINK &&
1754 		    !(ifp->flags & banned_flags)) {
1755 			*addr = ifp->addr;
1756 			err = 0;
1757 			break;
1758 		}
1759 	}
1760 	return err;
1761 }
1762 
1763 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1764 		    u32 banned_flags)
1765 {
1766 	struct inet6_dev *idev;
1767 	int err = -EADDRNOTAVAIL;
1768 
1769 	rcu_read_lock();
1770 	idev = __in6_dev_get(dev);
1771 	if (idev) {
1772 		read_lock_bh(&idev->lock);
1773 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1774 		read_unlock_bh(&idev->lock);
1775 	}
1776 	rcu_read_unlock();
1777 	return err;
1778 }
1779 
1780 static int ipv6_count_addresses(struct inet6_dev *idev)
1781 {
1782 	int cnt = 0;
1783 	struct inet6_ifaddr *ifp;
1784 
1785 	read_lock_bh(&idev->lock);
1786 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1787 		cnt++;
1788 	read_unlock_bh(&idev->lock);
1789 	return cnt;
1790 }
1791 
1792 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1793 		  const struct net_device *dev, int strict)
1794 {
1795 	return ipv6_chk_addr_and_flags(net, addr, dev, strict, IFA_F_TENTATIVE);
1796 }
1797 EXPORT_SYMBOL(ipv6_chk_addr);
1798 
1799 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1800 			    const struct net_device *dev, int strict,
1801 			    u32 banned_flags)
1802 {
1803 	struct inet6_ifaddr *ifp;
1804 	unsigned int hash = inet6_addr_hash(addr);
1805 	u32 ifp_flags;
1806 
1807 	rcu_read_lock_bh();
1808 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1809 		if (!net_eq(dev_net(ifp->idev->dev), net))
1810 			continue;
1811 		/* Decouple optimistic from tentative for evaluation here.
1812 		 * Ban optimistic addresses explicitly, when required.
1813 		 */
1814 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1815 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1816 			    : ifp->flags;
1817 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1818 		    !(ifp_flags&banned_flags) &&
1819 		    (!dev || ifp->idev->dev == dev ||
1820 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1821 			rcu_read_unlock_bh();
1822 			return 1;
1823 		}
1824 	}
1825 
1826 	rcu_read_unlock_bh();
1827 	return 0;
1828 }
1829 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1830 
1831 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1832 			       struct net_device *dev)
1833 {
1834 	unsigned int hash = inet6_addr_hash(addr);
1835 	struct inet6_ifaddr *ifp;
1836 
1837 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1838 		if (!net_eq(dev_net(ifp->idev->dev), net))
1839 			continue;
1840 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1841 			if (!dev || ifp->idev->dev == dev)
1842 				return true;
1843 		}
1844 	}
1845 	return false;
1846 }
1847 
1848 /* Compares an address/prefix_len with addresses on device @dev.
1849  * If one is found it returns true.
1850  */
1851 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1852 	const unsigned int prefix_len, struct net_device *dev)
1853 {
1854 	struct inet6_dev *idev;
1855 	struct inet6_ifaddr *ifa;
1856 	bool ret = false;
1857 
1858 	rcu_read_lock();
1859 	idev = __in6_dev_get(dev);
1860 	if (idev) {
1861 		read_lock_bh(&idev->lock);
1862 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1863 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1864 			if (ret)
1865 				break;
1866 		}
1867 		read_unlock_bh(&idev->lock);
1868 	}
1869 	rcu_read_unlock();
1870 
1871 	return ret;
1872 }
1873 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1874 
1875 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1876 {
1877 	struct inet6_dev *idev;
1878 	struct inet6_ifaddr *ifa;
1879 	int	onlink;
1880 
1881 	onlink = 0;
1882 	rcu_read_lock();
1883 	idev = __in6_dev_get(dev);
1884 	if (idev) {
1885 		read_lock_bh(&idev->lock);
1886 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1887 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1888 						   ifa->prefix_len);
1889 			if (onlink)
1890 				break;
1891 		}
1892 		read_unlock_bh(&idev->lock);
1893 	}
1894 	rcu_read_unlock();
1895 	return onlink;
1896 }
1897 EXPORT_SYMBOL(ipv6_chk_prefix);
1898 
1899 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1900 				     struct net_device *dev, int strict)
1901 {
1902 	struct inet6_ifaddr *ifp, *result = NULL;
1903 	unsigned int hash = inet6_addr_hash(addr);
1904 
1905 	rcu_read_lock_bh();
1906 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
1907 		if (!net_eq(dev_net(ifp->idev->dev), net))
1908 			continue;
1909 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1910 			if (!dev || ifp->idev->dev == dev ||
1911 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1912 				result = ifp;
1913 				in6_ifa_hold(ifp);
1914 				break;
1915 			}
1916 		}
1917 	}
1918 	rcu_read_unlock_bh();
1919 
1920 	return result;
1921 }
1922 
1923 /* Gets referenced address, destroys ifaddr */
1924 
1925 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1926 {
1927 	if (dad_failed)
1928 		ifp->flags |= IFA_F_DADFAILED;
1929 
1930 	if (ifp->flags&IFA_F_PERMANENT) {
1931 		spin_lock_bh(&ifp->lock);
1932 		addrconf_del_dad_work(ifp);
1933 		ifp->flags |= IFA_F_TENTATIVE;
1934 		spin_unlock_bh(&ifp->lock);
1935 		if (dad_failed)
1936 			ipv6_ifa_notify(0, ifp);
1937 		in6_ifa_put(ifp);
1938 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1939 		struct inet6_ifaddr *ifpub;
1940 		spin_lock_bh(&ifp->lock);
1941 		ifpub = ifp->ifpub;
1942 		if (ifpub) {
1943 			in6_ifa_hold(ifpub);
1944 			spin_unlock_bh(&ifp->lock);
1945 			ipv6_create_tempaddr(ifpub, ifp);
1946 			in6_ifa_put(ifpub);
1947 		} else {
1948 			spin_unlock_bh(&ifp->lock);
1949 		}
1950 		ipv6_del_addr(ifp);
1951 	} else {
1952 		ipv6_del_addr(ifp);
1953 	}
1954 }
1955 
1956 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1957 {
1958 	int err = -ENOENT;
1959 
1960 	spin_lock_bh(&ifp->lock);
1961 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1962 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1963 		err = 0;
1964 	}
1965 	spin_unlock_bh(&ifp->lock);
1966 
1967 	return err;
1968 }
1969 
1970 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1971 {
1972 	struct inet6_dev *idev = ifp->idev;
1973 	struct net *net = dev_net(ifp->idev->dev);
1974 
1975 	if (addrconf_dad_end(ifp)) {
1976 		in6_ifa_put(ifp);
1977 		return;
1978 	}
1979 
1980 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1981 			     ifp->idev->dev->name, &ifp->addr);
1982 
1983 	spin_lock_bh(&ifp->lock);
1984 
1985 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
1986 		int scope = ifp->scope;
1987 		u32 flags = ifp->flags;
1988 		struct in6_addr new_addr;
1989 		struct inet6_ifaddr *ifp2;
1990 		u32 valid_lft, preferred_lft;
1991 		int pfxlen = ifp->prefix_len;
1992 		int retries = ifp->stable_privacy_retry + 1;
1993 
1994 		if (retries > net->ipv6.sysctl.idgen_retries) {
1995 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
1996 					     ifp->idev->dev->name);
1997 			goto errdad;
1998 		}
1999 
2000 		new_addr = ifp->addr;
2001 		if (ipv6_generate_stable_address(&new_addr, retries,
2002 						 idev))
2003 			goto errdad;
2004 
2005 		valid_lft = ifp->valid_lft;
2006 		preferred_lft = ifp->prefered_lft;
2007 
2008 		spin_unlock_bh(&ifp->lock);
2009 
2010 		if (idev->cnf.max_addresses &&
2011 		    ipv6_count_addresses(idev) >=
2012 		    idev->cnf.max_addresses)
2013 			goto lock_errdad;
2014 
2015 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2016 				     ifp->idev->dev->name);
2017 
2018 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2019 				     scope, flags, valid_lft,
2020 				     preferred_lft);
2021 		if (IS_ERR(ifp2))
2022 			goto lock_errdad;
2023 
2024 		spin_lock_bh(&ifp2->lock);
2025 		ifp2->stable_privacy_retry = retries;
2026 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2027 		spin_unlock_bh(&ifp2->lock);
2028 
2029 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2030 		in6_ifa_put(ifp2);
2031 lock_errdad:
2032 		spin_lock_bh(&ifp->lock);
2033 	}
2034 
2035 errdad:
2036 	/* transition from _POSTDAD to _ERRDAD */
2037 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2038 	spin_unlock_bh(&ifp->lock);
2039 
2040 	addrconf_mod_dad_work(ifp, 0);
2041 	in6_ifa_put(ifp);
2042 }
2043 
2044 /* Join to solicited addr multicast group.
2045  * caller must hold RTNL */
2046 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2047 {
2048 	struct in6_addr maddr;
2049 
2050 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2051 		return;
2052 
2053 	addrconf_addr_solict_mult(addr, &maddr);
2054 	ipv6_dev_mc_inc(dev, &maddr);
2055 }
2056 
2057 /* caller must hold RTNL */
2058 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2059 {
2060 	struct in6_addr maddr;
2061 
2062 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2063 		return;
2064 
2065 	addrconf_addr_solict_mult(addr, &maddr);
2066 	__ipv6_dev_mc_dec(idev, &maddr);
2067 }
2068 
2069 /* caller must hold RTNL */
2070 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2071 {
2072 	struct in6_addr addr;
2073 
2074 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2075 		return;
2076 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2077 	if (ipv6_addr_any(&addr))
2078 		return;
2079 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2080 }
2081 
2082 /* caller must hold RTNL */
2083 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2084 {
2085 	struct in6_addr addr;
2086 
2087 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2088 		return;
2089 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2090 	if (ipv6_addr_any(&addr))
2091 		return;
2092 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2093 }
2094 
2095 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2096 {
2097 	switch (dev->addr_len) {
2098 	case ETH_ALEN:
2099 		memcpy(eui, dev->dev_addr, 3);
2100 		eui[3] = 0xFF;
2101 		eui[4] = 0xFE;
2102 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2103 		break;
2104 	case EUI64_ADDR_LEN:
2105 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2106 		eui[0] ^= 2;
2107 		break;
2108 	default:
2109 		return -1;
2110 	}
2111 
2112 	return 0;
2113 }
2114 
2115 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2116 {
2117 	union fwnet_hwaddr *ha;
2118 
2119 	if (dev->addr_len != FWNET_ALEN)
2120 		return -1;
2121 
2122 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2123 
2124 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2125 	eui[0] ^= 2;
2126 	return 0;
2127 }
2128 
2129 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2130 {
2131 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2132 	if (dev->addr_len != ARCNET_ALEN)
2133 		return -1;
2134 	memset(eui, 0, 7);
2135 	eui[7] = *(u8 *)dev->dev_addr;
2136 	return 0;
2137 }
2138 
2139 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2140 {
2141 	if (dev->addr_len != INFINIBAND_ALEN)
2142 		return -1;
2143 	memcpy(eui, dev->dev_addr + 12, 8);
2144 	eui[0] |= 2;
2145 	return 0;
2146 }
2147 
2148 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2149 {
2150 	if (addr == 0)
2151 		return -1;
2152 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2153 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2154 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2155 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2156 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2157 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2158 	eui[1] = 0;
2159 	eui[2] = 0x5E;
2160 	eui[3] = 0xFE;
2161 	memcpy(eui + 4, &addr, 4);
2162 	return 0;
2163 }
2164 
2165 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2166 {
2167 	if (dev->priv_flags & IFF_ISATAP)
2168 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2169 	return -1;
2170 }
2171 
2172 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2173 {
2174 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2175 }
2176 
2177 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2178 {
2179 	memcpy(eui, dev->perm_addr, 3);
2180 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2181 	eui[3] = 0xFF;
2182 	eui[4] = 0xFE;
2183 	eui[0] ^= 2;
2184 	return 0;
2185 }
2186 
2187 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2188 {
2189 	switch (dev->type) {
2190 	case ARPHRD_ETHER:
2191 	case ARPHRD_FDDI:
2192 		return addrconf_ifid_eui48(eui, dev);
2193 	case ARPHRD_ARCNET:
2194 		return addrconf_ifid_arcnet(eui, dev);
2195 	case ARPHRD_INFINIBAND:
2196 		return addrconf_ifid_infiniband(eui, dev);
2197 	case ARPHRD_SIT:
2198 		return addrconf_ifid_sit(eui, dev);
2199 	case ARPHRD_IPGRE:
2200 	case ARPHRD_TUNNEL:
2201 		return addrconf_ifid_gre(eui, dev);
2202 	case ARPHRD_6LOWPAN:
2203 		return addrconf_ifid_6lowpan(eui, dev);
2204 	case ARPHRD_IEEE1394:
2205 		return addrconf_ifid_ieee1394(eui, dev);
2206 	case ARPHRD_TUNNEL6:
2207 	case ARPHRD_IP6GRE:
2208 		return addrconf_ifid_ip6tnl(eui, dev);
2209 	}
2210 	return -1;
2211 }
2212 
2213 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2214 {
2215 	int err = -1;
2216 	struct inet6_ifaddr *ifp;
2217 
2218 	read_lock_bh(&idev->lock);
2219 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2220 		if (ifp->scope > IFA_LINK)
2221 			break;
2222 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2223 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2224 			err = 0;
2225 			break;
2226 		}
2227 	}
2228 	read_unlock_bh(&idev->lock);
2229 	return err;
2230 }
2231 
2232 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2233 static void ipv6_regen_rndid(struct inet6_dev *idev)
2234 {
2235 regen:
2236 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2237 	idev->rndid[0] &= ~0x02;
2238 
2239 	/*
2240 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2241 	 * check if generated address is not inappropriate
2242 	 *
2243 	 *  - Reserved subnet anycast (RFC 2526)
2244 	 *	11111101 11....11 1xxxxxxx
2245 	 *  - ISATAP (RFC4214) 6.1
2246 	 *	00-00-5E-FE-xx-xx-xx-xx
2247 	 *  - value 0
2248 	 *  - XXX: already assigned to an address on the device
2249 	 */
2250 	if (idev->rndid[0] == 0xfd &&
2251 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2252 	    (idev->rndid[7]&0x80))
2253 		goto regen;
2254 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2255 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2256 			goto regen;
2257 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2258 			goto regen;
2259 	}
2260 }
2261 
2262 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2263 {
2264 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2265 		ipv6_regen_rndid(idev);
2266 }
2267 
2268 /*
2269  *	Add prefix route.
2270  */
2271 
2272 static void
2273 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2274 		      unsigned long expires, u32 flags)
2275 {
2276 	struct fib6_config cfg = {
2277 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2278 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2279 		.fc_ifindex = dev->ifindex,
2280 		.fc_expires = expires,
2281 		.fc_dst_len = plen,
2282 		.fc_flags = RTF_UP | flags,
2283 		.fc_nlinfo.nl_net = dev_net(dev),
2284 		.fc_protocol = RTPROT_KERNEL,
2285 	};
2286 
2287 	cfg.fc_dst = *pfx;
2288 
2289 	/* Prevent useless cloning on PtP SIT.
2290 	   This thing is done here expecting that the whole
2291 	   class of non-broadcast devices need not cloning.
2292 	 */
2293 #if IS_ENABLED(CONFIG_IPV6_SIT)
2294 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2295 		cfg.fc_flags |= RTF_NONEXTHOP;
2296 #endif
2297 
2298 	ip6_route_add(&cfg, NULL);
2299 }
2300 
2301 
2302 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2303 						  int plen,
2304 						  const struct net_device *dev,
2305 						  u32 flags, u32 noflags)
2306 {
2307 	struct fib6_node *fn;
2308 	struct rt6_info *rt = NULL;
2309 	struct fib6_table *table;
2310 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2311 
2312 	table = fib6_get_table(dev_net(dev), tb_id);
2313 	if (!table)
2314 		return NULL;
2315 
2316 	read_lock_bh(&table->tb6_lock);
2317 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
2318 	if (!fn)
2319 		goto out;
2320 
2321 	noflags |= RTF_CACHE;
2322 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2323 		if (rt->dst.dev->ifindex != dev->ifindex)
2324 			continue;
2325 		if ((rt->rt6i_flags & flags) != flags)
2326 			continue;
2327 		if ((rt->rt6i_flags & noflags) != 0)
2328 			continue;
2329 		dst_hold(&rt->dst);
2330 		break;
2331 	}
2332 out:
2333 	read_unlock_bh(&table->tb6_lock);
2334 	return rt;
2335 }
2336 
2337 
2338 /* Create "default" multicast route to the interface */
2339 
2340 static void addrconf_add_mroute(struct net_device *dev)
2341 {
2342 	struct fib6_config cfg = {
2343 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2344 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2345 		.fc_ifindex = dev->ifindex,
2346 		.fc_dst_len = 8,
2347 		.fc_flags = RTF_UP,
2348 		.fc_nlinfo.nl_net = dev_net(dev),
2349 	};
2350 
2351 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2352 
2353 	ip6_route_add(&cfg, NULL);
2354 }
2355 
2356 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2357 {
2358 	struct inet6_dev *idev;
2359 
2360 	ASSERT_RTNL();
2361 
2362 	idev = ipv6_find_idev(dev);
2363 	if (!idev)
2364 		return ERR_PTR(-ENOBUFS);
2365 
2366 	if (idev->cnf.disable_ipv6)
2367 		return ERR_PTR(-EACCES);
2368 
2369 	/* Add default multicast route */
2370 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2371 		addrconf_add_mroute(dev);
2372 
2373 	return idev;
2374 }
2375 
2376 static void manage_tempaddrs(struct inet6_dev *idev,
2377 			     struct inet6_ifaddr *ifp,
2378 			     __u32 valid_lft, __u32 prefered_lft,
2379 			     bool create, unsigned long now)
2380 {
2381 	u32 flags;
2382 	struct inet6_ifaddr *ift;
2383 
2384 	read_lock_bh(&idev->lock);
2385 	/* update all temporary addresses in the list */
2386 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2387 		int age, max_valid, max_prefered;
2388 
2389 		if (ifp != ift->ifpub)
2390 			continue;
2391 
2392 		/* RFC 4941 section 3.3:
2393 		 * If a received option will extend the lifetime of a public
2394 		 * address, the lifetimes of temporary addresses should
2395 		 * be extended, subject to the overall constraint that no
2396 		 * temporary addresses should ever remain "valid" or "preferred"
2397 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2398 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2399 		 */
2400 		age = (now - ift->cstamp) / HZ;
2401 		max_valid = idev->cnf.temp_valid_lft - age;
2402 		if (max_valid < 0)
2403 			max_valid = 0;
2404 
2405 		max_prefered = idev->cnf.temp_prefered_lft -
2406 			       idev->desync_factor - age;
2407 		if (max_prefered < 0)
2408 			max_prefered = 0;
2409 
2410 		if (valid_lft > max_valid)
2411 			valid_lft = max_valid;
2412 
2413 		if (prefered_lft > max_prefered)
2414 			prefered_lft = max_prefered;
2415 
2416 		spin_lock(&ift->lock);
2417 		flags = ift->flags;
2418 		ift->valid_lft = valid_lft;
2419 		ift->prefered_lft = prefered_lft;
2420 		ift->tstamp = now;
2421 		if (prefered_lft > 0)
2422 			ift->flags &= ~IFA_F_DEPRECATED;
2423 
2424 		spin_unlock(&ift->lock);
2425 		if (!(flags&IFA_F_TENTATIVE))
2426 			ipv6_ifa_notify(0, ift);
2427 	}
2428 
2429 	if ((create || list_empty(&idev->tempaddr_list)) &&
2430 	    idev->cnf.use_tempaddr > 0) {
2431 		/* When a new public address is created as described
2432 		 * in [ADDRCONF], also create a new temporary address.
2433 		 * Also create a temporary address if it's enabled but
2434 		 * no temporary address currently exists.
2435 		 */
2436 		read_unlock_bh(&idev->lock);
2437 		ipv6_create_tempaddr(ifp, NULL);
2438 	} else {
2439 		read_unlock_bh(&idev->lock);
2440 	}
2441 }
2442 
2443 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2444 {
2445 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2446 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2447 }
2448 
2449 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2450 				 const struct prefix_info *pinfo,
2451 				 struct inet6_dev *in6_dev,
2452 				 const struct in6_addr *addr, int addr_type,
2453 				 u32 addr_flags, bool sllao, bool tokenized,
2454 				 __u32 valid_lft, u32 prefered_lft)
2455 {
2456 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2457 	int create = 0, update_lft = 0;
2458 
2459 	if (!ifp && valid_lft) {
2460 		int max_addresses = in6_dev->cnf.max_addresses;
2461 
2462 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2463 		if (in6_dev->cnf.optimistic_dad &&
2464 		    !net->ipv6.devconf_all->forwarding && sllao)
2465 			addr_flags |= IFA_F_OPTIMISTIC;
2466 #endif
2467 
2468 		/* Do not allow to create too much of autoconfigured
2469 		 * addresses; this would be too easy way to crash kernel.
2470 		 */
2471 		if (!max_addresses ||
2472 		    ipv6_count_addresses(in6_dev) < max_addresses)
2473 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2474 					    pinfo->prefix_len,
2475 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2476 					    addr_flags, valid_lft,
2477 					    prefered_lft);
2478 
2479 		if (IS_ERR_OR_NULL(ifp))
2480 			return -1;
2481 
2482 		update_lft = 0;
2483 		create = 1;
2484 		spin_lock_bh(&ifp->lock);
2485 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2486 		ifp->cstamp = jiffies;
2487 		ifp->tokenized = tokenized;
2488 		spin_unlock_bh(&ifp->lock);
2489 		addrconf_dad_start(ifp);
2490 	}
2491 
2492 	if (ifp) {
2493 		u32 flags;
2494 		unsigned long now;
2495 		u32 stored_lft;
2496 
2497 		/* update lifetime (RFC2462 5.5.3 e) */
2498 		spin_lock_bh(&ifp->lock);
2499 		now = jiffies;
2500 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2501 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2502 		else
2503 			stored_lft = 0;
2504 		if (!update_lft && !create && stored_lft) {
2505 			const u32 minimum_lft = min_t(u32,
2506 				stored_lft, MIN_VALID_LIFETIME);
2507 			valid_lft = max(valid_lft, minimum_lft);
2508 
2509 			/* RFC4862 Section 5.5.3e:
2510 			 * "Note that the preferred lifetime of the
2511 			 *  corresponding address is always reset to
2512 			 *  the Preferred Lifetime in the received
2513 			 *  Prefix Information option, regardless of
2514 			 *  whether the valid lifetime is also reset or
2515 			 *  ignored."
2516 			 *
2517 			 * So we should always update prefered_lft here.
2518 			 */
2519 			update_lft = 1;
2520 		}
2521 
2522 		if (update_lft) {
2523 			ifp->valid_lft = valid_lft;
2524 			ifp->prefered_lft = prefered_lft;
2525 			ifp->tstamp = now;
2526 			flags = ifp->flags;
2527 			ifp->flags &= ~IFA_F_DEPRECATED;
2528 			spin_unlock_bh(&ifp->lock);
2529 
2530 			if (!(flags&IFA_F_TENTATIVE))
2531 				ipv6_ifa_notify(0, ifp);
2532 		} else
2533 			spin_unlock_bh(&ifp->lock);
2534 
2535 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2536 				 create, now);
2537 
2538 		in6_ifa_put(ifp);
2539 		addrconf_verify();
2540 	}
2541 
2542 	return 0;
2543 }
2544 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2545 
2546 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2547 {
2548 	struct prefix_info *pinfo;
2549 	__u32 valid_lft;
2550 	__u32 prefered_lft;
2551 	int addr_type, err;
2552 	u32 addr_flags = 0;
2553 	struct inet6_dev *in6_dev;
2554 	struct net *net = dev_net(dev);
2555 
2556 	pinfo = (struct prefix_info *) opt;
2557 
2558 	if (len < sizeof(struct prefix_info)) {
2559 		ADBG("addrconf: prefix option too short\n");
2560 		return;
2561 	}
2562 
2563 	/*
2564 	 *	Validation checks ([ADDRCONF], page 19)
2565 	 */
2566 
2567 	addr_type = ipv6_addr_type(&pinfo->prefix);
2568 
2569 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2570 		return;
2571 
2572 	valid_lft = ntohl(pinfo->valid);
2573 	prefered_lft = ntohl(pinfo->prefered);
2574 
2575 	if (prefered_lft > valid_lft) {
2576 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2577 		return;
2578 	}
2579 
2580 	in6_dev = in6_dev_get(dev);
2581 
2582 	if (!in6_dev) {
2583 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2584 				    dev->name);
2585 		return;
2586 	}
2587 
2588 	/*
2589 	 *	Two things going on here:
2590 	 *	1) Add routes for on-link prefixes
2591 	 *	2) Configure prefixes with the auto flag set
2592 	 */
2593 
2594 	if (pinfo->onlink) {
2595 		struct rt6_info *rt;
2596 		unsigned long rt_expires;
2597 
2598 		/* Avoid arithmetic overflow. Really, we could
2599 		 * save rt_expires in seconds, likely valid_lft,
2600 		 * but it would require division in fib gc, that it
2601 		 * not good.
2602 		 */
2603 		if (HZ > USER_HZ)
2604 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2605 		else
2606 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2607 
2608 		if (addrconf_finite_timeout(rt_expires))
2609 			rt_expires *= HZ;
2610 
2611 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2612 					       pinfo->prefix_len,
2613 					       dev,
2614 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2615 					       RTF_GATEWAY | RTF_DEFAULT);
2616 
2617 		if (rt) {
2618 			/* Autoconf prefix route */
2619 			if (valid_lft == 0) {
2620 				ip6_del_rt(rt);
2621 				rt = NULL;
2622 			} else if (addrconf_finite_timeout(rt_expires)) {
2623 				/* not infinity */
2624 				rt6_set_expires(rt, jiffies + rt_expires);
2625 			} else {
2626 				rt6_clean_expires(rt);
2627 			}
2628 		} else if (valid_lft) {
2629 			clock_t expires = 0;
2630 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2631 			if (addrconf_finite_timeout(rt_expires)) {
2632 				/* not infinity */
2633 				flags |= RTF_EXPIRES;
2634 				expires = jiffies_to_clock_t(rt_expires);
2635 			}
2636 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2637 					      dev, expires, flags);
2638 		}
2639 		ip6_rt_put(rt);
2640 	}
2641 
2642 	/* Try to figure out our local address for this prefix */
2643 
2644 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2645 		struct in6_addr addr;
2646 		bool tokenized = false, dev_addr_generated = false;
2647 
2648 		if (pinfo->prefix_len == 64) {
2649 			memcpy(&addr, &pinfo->prefix, 8);
2650 
2651 			if (!ipv6_addr_any(&in6_dev->token)) {
2652 				read_lock_bh(&in6_dev->lock);
2653 				memcpy(addr.s6_addr + 8,
2654 				       in6_dev->token.s6_addr + 8, 8);
2655 				read_unlock_bh(&in6_dev->lock);
2656 				tokenized = true;
2657 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2658 				   !ipv6_generate_stable_address(&addr, 0,
2659 								 in6_dev)) {
2660 				addr_flags |= IFA_F_STABLE_PRIVACY;
2661 				goto ok;
2662 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2663 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2664 				goto put;
2665 			} else {
2666 				dev_addr_generated = true;
2667 			}
2668 			goto ok;
2669 		}
2670 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2671 				    pinfo->prefix_len);
2672 		goto put;
2673 
2674 ok:
2675 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2676 						   &addr, addr_type,
2677 						   addr_flags, sllao,
2678 						   tokenized, valid_lft,
2679 						   prefered_lft);
2680 		if (err)
2681 			goto put;
2682 
2683 		/* Ignore error case here because previous prefix add addr was
2684 		 * successful which will be notified.
2685 		 */
2686 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2687 					      addr_type, addr_flags, sllao,
2688 					      tokenized, valid_lft,
2689 					      prefered_lft,
2690 					      dev_addr_generated);
2691 	}
2692 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2693 put:
2694 	in6_dev_put(in6_dev);
2695 }
2696 
2697 /*
2698  *	Set destination address.
2699  *	Special case for SIT interfaces where we create a new "virtual"
2700  *	device.
2701  */
2702 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2703 {
2704 	struct in6_ifreq ireq;
2705 	struct net_device *dev;
2706 	int err = -EINVAL;
2707 
2708 	rtnl_lock();
2709 
2710 	err = -EFAULT;
2711 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2712 		goto err_exit;
2713 
2714 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2715 
2716 	err = -ENODEV;
2717 	if (!dev)
2718 		goto err_exit;
2719 
2720 #if IS_ENABLED(CONFIG_IPV6_SIT)
2721 	if (dev->type == ARPHRD_SIT) {
2722 		const struct net_device_ops *ops = dev->netdev_ops;
2723 		struct ifreq ifr;
2724 		struct ip_tunnel_parm p;
2725 
2726 		err = -EADDRNOTAVAIL;
2727 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2728 			goto err_exit;
2729 
2730 		memset(&p, 0, sizeof(p));
2731 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2732 		p.iph.saddr = 0;
2733 		p.iph.version = 4;
2734 		p.iph.ihl = 5;
2735 		p.iph.protocol = IPPROTO_IPV6;
2736 		p.iph.ttl = 64;
2737 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2738 
2739 		if (ops->ndo_do_ioctl) {
2740 			mm_segment_t oldfs = get_fs();
2741 
2742 			set_fs(KERNEL_DS);
2743 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2744 			set_fs(oldfs);
2745 		} else
2746 			err = -EOPNOTSUPP;
2747 
2748 		if (err == 0) {
2749 			err = -ENOBUFS;
2750 			dev = __dev_get_by_name(net, p.name);
2751 			if (!dev)
2752 				goto err_exit;
2753 			err = dev_open(dev);
2754 		}
2755 	}
2756 #endif
2757 
2758 err_exit:
2759 	rtnl_unlock();
2760 	return err;
2761 }
2762 
2763 static int ipv6_mc_config(struct sock *sk, bool join,
2764 			  const struct in6_addr *addr, int ifindex)
2765 {
2766 	int ret;
2767 
2768 	ASSERT_RTNL();
2769 
2770 	lock_sock(sk);
2771 	if (join)
2772 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2773 	else
2774 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2775 	release_sock(sk);
2776 
2777 	return ret;
2778 }
2779 
2780 /*
2781  *	Manual configuration of address on an interface
2782  */
2783 static int inet6_addr_add(struct net *net, int ifindex,
2784 			  const struct in6_addr *pfx,
2785 			  const struct in6_addr *peer_pfx,
2786 			  unsigned int plen, __u32 ifa_flags,
2787 			  __u32 prefered_lft, __u32 valid_lft)
2788 {
2789 	struct inet6_ifaddr *ifp;
2790 	struct inet6_dev *idev;
2791 	struct net_device *dev;
2792 	unsigned long timeout;
2793 	clock_t expires;
2794 	int scope;
2795 	u32 flags;
2796 
2797 	ASSERT_RTNL();
2798 
2799 	if (plen > 128)
2800 		return -EINVAL;
2801 
2802 	/* check the lifetime */
2803 	if (!valid_lft || prefered_lft > valid_lft)
2804 		return -EINVAL;
2805 
2806 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2807 		return -EINVAL;
2808 
2809 	dev = __dev_get_by_index(net, ifindex);
2810 	if (!dev)
2811 		return -ENODEV;
2812 
2813 	idev = addrconf_add_dev(dev);
2814 	if (IS_ERR(idev))
2815 		return PTR_ERR(idev);
2816 
2817 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2818 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2819 					 true, pfx, ifindex);
2820 
2821 		if (ret < 0)
2822 			return ret;
2823 	}
2824 
2825 	scope = ipv6_addr_scope(pfx);
2826 
2827 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2828 	if (addrconf_finite_timeout(timeout)) {
2829 		expires = jiffies_to_clock_t(timeout * HZ);
2830 		valid_lft = timeout;
2831 		flags = RTF_EXPIRES;
2832 	} else {
2833 		expires = 0;
2834 		flags = 0;
2835 		ifa_flags |= IFA_F_PERMANENT;
2836 	}
2837 
2838 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2839 	if (addrconf_finite_timeout(timeout)) {
2840 		if (timeout == 0)
2841 			ifa_flags |= IFA_F_DEPRECATED;
2842 		prefered_lft = timeout;
2843 	}
2844 
2845 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2846 			    valid_lft, prefered_lft);
2847 
2848 	if (!IS_ERR(ifp)) {
2849 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2850 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2851 					      expires, flags);
2852 		}
2853 
2854 		/*
2855 		 * Note that section 3.1 of RFC 4429 indicates
2856 		 * that the Optimistic flag should not be set for
2857 		 * manually configured addresses
2858 		 */
2859 		addrconf_dad_start(ifp);
2860 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2861 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2862 					 true, jiffies);
2863 		in6_ifa_put(ifp);
2864 		addrconf_verify_rtnl();
2865 		return 0;
2866 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2867 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2868 			       false, pfx, ifindex);
2869 	}
2870 
2871 	return PTR_ERR(ifp);
2872 }
2873 
2874 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2875 			  const struct in6_addr *pfx, unsigned int plen)
2876 {
2877 	struct inet6_ifaddr *ifp;
2878 	struct inet6_dev *idev;
2879 	struct net_device *dev;
2880 
2881 	if (plen > 128)
2882 		return -EINVAL;
2883 
2884 	dev = __dev_get_by_index(net, ifindex);
2885 	if (!dev)
2886 		return -ENODEV;
2887 
2888 	idev = __in6_dev_get(dev);
2889 	if (!idev)
2890 		return -ENXIO;
2891 
2892 	read_lock_bh(&idev->lock);
2893 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2894 		if (ifp->prefix_len == plen &&
2895 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2896 			in6_ifa_hold(ifp);
2897 			read_unlock_bh(&idev->lock);
2898 
2899 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2900 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2901 				manage_tempaddrs(idev, ifp, 0, 0, false,
2902 						 jiffies);
2903 			ipv6_del_addr(ifp);
2904 			addrconf_verify_rtnl();
2905 			if (ipv6_addr_is_multicast(pfx)) {
2906 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2907 					       false, pfx, dev->ifindex);
2908 			}
2909 			return 0;
2910 		}
2911 	}
2912 	read_unlock_bh(&idev->lock);
2913 	return -EADDRNOTAVAIL;
2914 }
2915 
2916 
2917 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2918 {
2919 	struct in6_ifreq ireq;
2920 	int err;
2921 
2922 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2923 		return -EPERM;
2924 
2925 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2926 		return -EFAULT;
2927 
2928 	rtnl_lock();
2929 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2930 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2931 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2932 	rtnl_unlock();
2933 	return err;
2934 }
2935 
2936 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2937 {
2938 	struct in6_ifreq ireq;
2939 	int err;
2940 
2941 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2942 		return -EPERM;
2943 
2944 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2945 		return -EFAULT;
2946 
2947 	rtnl_lock();
2948 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
2949 			     ireq.ifr6_prefixlen);
2950 	rtnl_unlock();
2951 	return err;
2952 }
2953 
2954 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2955 		     int plen, int scope)
2956 {
2957 	struct inet6_ifaddr *ifp;
2958 
2959 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
2960 			    scope, IFA_F_PERMANENT,
2961 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2962 	if (!IS_ERR(ifp)) {
2963 		spin_lock_bh(&ifp->lock);
2964 		ifp->flags &= ~IFA_F_TENTATIVE;
2965 		spin_unlock_bh(&ifp->lock);
2966 		rt_genid_bump_ipv6(dev_net(idev->dev));
2967 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2968 		in6_ifa_put(ifp);
2969 	}
2970 }
2971 
2972 #if IS_ENABLED(CONFIG_IPV6_SIT)
2973 static void sit_add_v4_addrs(struct inet6_dev *idev)
2974 {
2975 	struct in6_addr addr;
2976 	struct net_device *dev;
2977 	struct net *net = dev_net(idev->dev);
2978 	int scope, plen;
2979 	u32 pflags = 0;
2980 
2981 	ASSERT_RTNL();
2982 
2983 	memset(&addr, 0, sizeof(struct in6_addr));
2984 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2985 
2986 	if (idev->dev->flags&IFF_POINTOPOINT) {
2987 		addr.s6_addr32[0] = htonl(0xfe800000);
2988 		scope = IFA_LINK;
2989 		plen = 64;
2990 	} else {
2991 		scope = IPV6_ADDR_COMPATv4;
2992 		plen = 96;
2993 		pflags |= RTF_NONEXTHOP;
2994 	}
2995 
2996 	if (addr.s6_addr32[3]) {
2997 		add_addr(idev, &addr, plen, scope);
2998 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags);
2999 		return;
3000 	}
3001 
3002 	for_each_netdev(net, dev) {
3003 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3004 		if (in_dev && (dev->flags & IFF_UP)) {
3005 			struct in_ifaddr *ifa;
3006 
3007 			int flag = scope;
3008 
3009 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3010 
3011 				addr.s6_addr32[3] = ifa->ifa_local;
3012 
3013 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3014 					continue;
3015 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3016 					if (idev->dev->flags&IFF_POINTOPOINT)
3017 						continue;
3018 					flag |= IFA_HOST;
3019 				}
3020 
3021 				add_addr(idev, &addr, plen, flag);
3022 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3023 						      pflags);
3024 			}
3025 		}
3026 	}
3027 }
3028 #endif
3029 
3030 static void init_loopback(struct net_device *dev)
3031 {
3032 	struct inet6_dev  *idev;
3033 	struct net_device *sp_dev;
3034 	struct inet6_ifaddr *sp_ifa;
3035 	struct rt6_info *sp_rt;
3036 
3037 	/* ::1 */
3038 
3039 	ASSERT_RTNL();
3040 
3041 	idev = ipv6_find_idev(dev);
3042 	if (!idev) {
3043 		pr_debug("%s: add_dev failed\n", __func__);
3044 		return;
3045 	}
3046 
3047 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3048 
3049 	/* Add routes to other interface's IPv6 addresses */
3050 	for_each_netdev(dev_net(dev), sp_dev) {
3051 		if (!strcmp(sp_dev->name, dev->name))
3052 			continue;
3053 
3054 		idev = __in6_dev_get(sp_dev);
3055 		if (!idev)
3056 			continue;
3057 
3058 		read_lock_bh(&idev->lock);
3059 		list_for_each_entry(sp_ifa, &idev->addr_list, if_list) {
3060 
3061 			if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
3062 				continue;
3063 
3064 			if (sp_ifa->rt) {
3065 				/* This dst has been added to garbage list when
3066 				 * lo device down, release this obsolete dst and
3067 				 * reallocate a new router for ifa.
3068 				 */
3069 				if (!atomic_read(&sp_ifa->rt->rt6i_ref)) {
3070 					ip6_rt_put(sp_ifa->rt);
3071 					sp_ifa->rt = NULL;
3072 				} else {
3073 					continue;
3074 				}
3075 			}
3076 
3077 			sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, false);
3078 
3079 			/* Failure cases are ignored */
3080 			if (!IS_ERR(sp_rt)) {
3081 				sp_ifa->rt = sp_rt;
3082 				ip6_ins_rt(sp_rt);
3083 			}
3084 		}
3085 		read_unlock_bh(&idev->lock);
3086 	}
3087 }
3088 
3089 void addrconf_add_linklocal(struct inet6_dev *idev,
3090 			    const struct in6_addr *addr, u32 flags)
3091 {
3092 	struct inet6_ifaddr *ifp;
3093 	u32 addr_flags = flags | IFA_F_PERMANENT;
3094 
3095 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3096 	if (idev->cnf.optimistic_dad &&
3097 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3098 		addr_flags |= IFA_F_OPTIMISTIC;
3099 #endif
3100 
3101 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3102 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
3103 	if (!IS_ERR(ifp)) {
3104 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
3105 		addrconf_dad_start(ifp);
3106 		in6_ifa_put(ifp);
3107 	}
3108 }
3109 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3110 
3111 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3112 {
3113 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3114 		return true;
3115 
3116 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3117 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3118 		return true;
3119 
3120 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3121 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3122 		return true;
3123 
3124 	return false;
3125 }
3126 
3127 static int ipv6_generate_stable_address(struct in6_addr *address,
3128 					u8 dad_count,
3129 					const struct inet6_dev *idev)
3130 {
3131 	static DEFINE_SPINLOCK(lock);
3132 	static __u32 digest[SHA_DIGEST_WORDS];
3133 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3134 
3135 	static union {
3136 		char __data[SHA_MESSAGE_BYTES];
3137 		struct {
3138 			struct in6_addr secret;
3139 			__be32 prefix[2];
3140 			unsigned char hwaddr[MAX_ADDR_LEN];
3141 			u8 dad_count;
3142 		} __packed;
3143 	} data;
3144 
3145 	struct in6_addr secret;
3146 	struct in6_addr temp;
3147 	struct net *net = dev_net(idev->dev);
3148 
3149 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3150 
3151 	if (idev->cnf.stable_secret.initialized)
3152 		secret = idev->cnf.stable_secret.secret;
3153 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3154 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3155 	else
3156 		return -1;
3157 
3158 retry:
3159 	spin_lock_bh(&lock);
3160 
3161 	sha_init(digest);
3162 	memset(&data, 0, sizeof(data));
3163 	memset(workspace, 0, sizeof(workspace));
3164 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3165 	data.prefix[0] = address->s6_addr32[0];
3166 	data.prefix[1] = address->s6_addr32[1];
3167 	data.secret = secret;
3168 	data.dad_count = dad_count;
3169 
3170 	sha_transform(digest, data.__data, workspace);
3171 
3172 	temp = *address;
3173 	temp.s6_addr32[2] = (__force __be32)digest[0];
3174 	temp.s6_addr32[3] = (__force __be32)digest[1];
3175 
3176 	spin_unlock_bh(&lock);
3177 
3178 	if (ipv6_reserved_interfaceid(temp)) {
3179 		dad_count++;
3180 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3181 			return -1;
3182 		goto retry;
3183 	}
3184 
3185 	*address = temp;
3186 	return 0;
3187 }
3188 
3189 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3190 {
3191 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3192 
3193 	if (s->initialized)
3194 		return;
3195 	s = &idev->cnf.stable_secret;
3196 	get_random_bytes(&s->secret, sizeof(s->secret));
3197 	s->initialized = true;
3198 }
3199 
3200 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3201 {
3202 	struct in6_addr addr;
3203 
3204 	/* no link local addresses on L3 master devices */
3205 	if (netif_is_l3_master(idev->dev))
3206 		return;
3207 
3208 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3209 
3210 	switch (idev->cnf.addr_gen_mode) {
3211 	case IN6_ADDR_GEN_MODE_RANDOM:
3212 		ipv6_gen_mode_random_init(idev);
3213 		/* fallthrough */
3214 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3215 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3216 			addrconf_add_linklocal(idev, &addr,
3217 					       IFA_F_STABLE_PRIVACY);
3218 		else if (prefix_route)
3219 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3220 		break;
3221 	case IN6_ADDR_GEN_MODE_EUI64:
3222 		/* addrconf_add_linklocal also adds a prefix_route and we
3223 		 * only need to care about prefix routes if ipv6_generate_eui64
3224 		 * couldn't generate one.
3225 		 */
3226 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3227 			addrconf_add_linklocal(idev, &addr, 0);
3228 		else if (prefix_route)
3229 			addrconf_prefix_route(&addr, 64, idev->dev, 0, 0);
3230 		break;
3231 	case IN6_ADDR_GEN_MODE_NONE:
3232 	default:
3233 		/* will not add any link local address */
3234 		break;
3235 	}
3236 }
3237 
3238 static void addrconf_dev_config(struct net_device *dev)
3239 {
3240 	struct inet6_dev *idev;
3241 
3242 	ASSERT_RTNL();
3243 
3244 	if ((dev->type != ARPHRD_ETHER) &&
3245 	    (dev->type != ARPHRD_FDDI) &&
3246 	    (dev->type != ARPHRD_ARCNET) &&
3247 	    (dev->type != ARPHRD_INFINIBAND) &&
3248 	    (dev->type != ARPHRD_IEEE1394) &&
3249 	    (dev->type != ARPHRD_TUNNEL6) &&
3250 	    (dev->type != ARPHRD_6LOWPAN) &&
3251 	    (dev->type != ARPHRD_IP6GRE) &&
3252 	    (dev->type != ARPHRD_IPGRE) &&
3253 	    (dev->type != ARPHRD_TUNNEL) &&
3254 	    (dev->type != ARPHRD_NONE)) {
3255 		/* Alas, we support only Ethernet autoconfiguration. */
3256 		return;
3257 	}
3258 
3259 	idev = addrconf_add_dev(dev);
3260 	if (IS_ERR(idev))
3261 		return;
3262 
3263 	/* this device type has no EUI support */
3264 	if (dev->type == ARPHRD_NONE &&
3265 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3266 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3267 
3268 	addrconf_addr_gen(idev, false);
3269 }
3270 
3271 #if IS_ENABLED(CONFIG_IPV6_SIT)
3272 static void addrconf_sit_config(struct net_device *dev)
3273 {
3274 	struct inet6_dev *idev;
3275 
3276 	ASSERT_RTNL();
3277 
3278 	/*
3279 	 * Configure the tunnel with one of our IPv4
3280 	 * addresses... we should configure all of
3281 	 * our v4 addrs in the tunnel
3282 	 */
3283 
3284 	idev = ipv6_find_idev(dev);
3285 	if (!idev) {
3286 		pr_debug("%s: add_dev failed\n", __func__);
3287 		return;
3288 	}
3289 
3290 	if (dev->priv_flags & IFF_ISATAP) {
3291 		addrconf_addr_gen(idev, false);
3292 		return;
3293 	}
3294 
3295 	sit_add_v4_addrs(idev);
3296 
3297 	if (dev->flags&IFF_POINTOPOINT)
3298 		addrconf_add_mroute(dev);
3299 }
3300 #endif
3301 
3302 #if IS_ENABLED(CONFIG_NET_IPGRE)
3303 static void addrconf_gre_config(struct net_device *dev)
3304 {
3305 	struct inet6_dev *idev;
3306 
3307 	ASSERT_RTNL();
3308 
3309 	idev = ipv6_find_idev(dev);
3310 	if (!idev) {
3311 		pr_debug("%s: add_dev failed\n", __func__);
3312 		return;
3313 	}
3314 
3315 	addrconf_addr_gen(idev, true);
3316 	if (dev->flags & IFF_POINTOPOINT)
3317 		addrconf_add_mroute(dev);
3318 }
3319 #endif
3320 
3321 static int fixup_permanent_addr(struct inet6_dev *idev,
3322 				struct inet6_ifaddr *ifp)
3323 {
3324 	/* rt6i_ref == 0 means the host route was removed from the
3325 	 * FIB, for example, if 'lo' device is taken down. In that
3326 	 * case regenerate the host route.
3327 	 */
3328 	if (!ifp->rt || !atomic_read(&ifp->rt->rt6i_ref)) {
3329 		struct rt6_info *rt, *prev;
3330 
3331 		rt = addrconf_dst_alloc(idev, &ifp->addr, false);
3332 		if (unlikely(IS_ERR(rt)))
3333 			return PTR_ERR(rt);
3334 
3335 		/* ifp->rt can be accessed outside of rtnl */
3336 		spin_lock(&ifp->lock);
3337 		prev = ifp->rt;
3338 		ifp->rt = rt;
3339 		spin_unlock(&ifp->lock);
3340 
3341 		ip6_rt_put(prev);
3342 	}
3343 
3344 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3345 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3346 				      idev->dev, 0, 0);
3347 	}
3348 
3349 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3350 		addrconf_dad_start(ifp);
3351 
3352 	return 0;
3353 }
3354 
3355 static void addrconf_permanent_addr(struct net_device *dev)
3356 {
3357 	struct inet6_ifaddr *ifp, *tmp;
3358 	struct inet6_dev *idev;
3359 
3360 	idev = __in6_dev_get(dev);
3361 	if (!idev)
3362 		return;
3363 
3364 	write_lock_bh(&idev->lock);
3365 
3366 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3367 		if ((ifp->flags & IFA_F_PERMANENT) &&
3368 		    fixup_permanent_addr(idev, ifp) < 0) {
3369 			write_unlock_bh(&idev->lock);
3370 			ipv6_del_addr(ifp);
3371 			write_lock_bh(&idev->lock);
3372 
3373 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3374 					     idev->dev->name, &ifp->addr);
3375 		}
3376 	}
3377 
3378 	write_unlock_bh(&idev->lock);
3379 }
3380 
3381 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3382 			   void *ptr)
3383 {
3384 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3385 	struct netdev_notifier_changeupper_info *info;
3386 	struct inet6_dev *idev = __in6_dev_get(dev);
3387 	int run_pending = 0;
3388 	int err;
3389 
3390 	switch (event) {
3391 	case NETDEV_REGISTER:
3392 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3393 			idev = ipv6_add_dev(dev);
3394 			if (IS_ERR(idev))
3395 				return notifier_from_errno(PTR_ERR(idev));
3396 		}
3397 		break;
3398 
3399 	case NETDEV_CHANGEMTU:
3400 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3401 		if (dev->mtu < IPV6_MIN_MTU) {
3402 			addrconf_ifdown(dev, 1);
3403 			break;
3404 		}
3405 
3406 		if (idev) {
3407 			rt6_mtu_change(dev, dev->mtu);
3408 			idev->cnf.mtu6 = dev->mtu;
3409 			break;
3410 		}
3411 
3412 		/* allocate new idev */
3413 		idev = ipv6_add_dev(dev);
3414 		if (IS_ERR(idev))
3415 			break;
3416 
3417 		/* device is still not ready */
3418 		if (!(idev->if_flags & IF_READY))
3419 			break;
3420 
3421 		run_pending = 1;
3422 
3423 		/* fall through */
3424 
3425 	case NETDEV_UP:
3426 	case NETDEV_CHANGE:
3427 		if (dev->flags & IFF_SLAVE)
3428 			break;
3429 
3430 		if (idev && idev->cnf.disable_ipv6)
3431 			break;
3432 
3433 		if (event == NETDEV_UP) {
3434 			/* restore routes for permanent addresses */
3435 			addrconf_permanent_addr(dev);
3436 
3437 			if (!addrconf_qdisc_ok(dev)) {
3438 				/* device is not ready yet. */
3439 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3440 					dev->name);
3441 				break;
3442 			}
3443 
3444 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3445 				idev = ipv6_add_dev(dev);
3446 
3447 			if (!IS_ERR_OR_NULL(idev)) {
3448 				idev->if_flags |= IF_READY;
3449 				run_pending = 1;
3450 			}
3451 		} else if (event == NETDEV_CHANGE) {
3452 			if (!addrconf_qdisc_ok(dev)) {
3453 				/* device is still not ready. */
3454 				break;
3455 			}
3456 
3457 			if (idev) {
3458 				if (idev->if_flags & IF_READY) {
3459 					/* device is already configured -
3460 					 * but resend MLD reports, we might
3461 					 * have roamed and need to update
3462 					 * multicast snooping switches
3463 					 */
3464 					ipv6_mc_up(idev);
3465 					break;
3466 				}
3467 				idev->if_flags |= IF_READY;
3468 			}
3469 
3470 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3471 				dev->name);
3472 
3473 			run_pending = 1;
3474 		}
3475 
3476 		switch (dev->type) {
3477 #if IS_ENABLED(CONFIG_IPV6_SIT)
3478 		case ARPHRD_SIT:
3479 			addrconf_sit_config(dev);
3480 			break;
3481 #endif
3482 #if IS_ENABLED(CONFIG_NET_IPGRE)
3483 		case ARPHRD_IPGRE:
3484 			addrconf_gre_config(dev);
3485 			break;
3486 #endif
3487 		case ARPHRD_LOOPBACK:
3488 			init_loopback(dev);
3489 			break;
3490 
3491 		default:
3492 			addrconf_dev_config(dev);
3493 			break;
3494 		}
3495 
3496 		if (!IS_ERR_OR_NULL(idev)) {
3497 			if (run_pending)
3498 				addrconf_dad_run(idev);
3499 
3500 			/*
3501 			 * If the MTU changed during the interface down,
3502 			 * when the interface up, the changed MTU must be
3503 			 * reflected in the idev as well as routers.
3504 			 */
3505 			if (idev->cnf.mtu6 != dev->mtu &&
3506 			    dev->mtu >= IPV6_MIN_MTU) {
3507 				rt6_mtu_change(dev, dev->mtu);
3508 				idev->cnf.mtu6 = dev->mtu;
3509 			}
3510 			idev->tstamp = jiffies;
3511 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3512 
3513 			/*
3514 			 * If the changed mtu during down is lower than
3515 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3516 			 */
3517 			if (dev->mtu < IPV6_MIN_MTU)
3518 				addrconf_ifdown(dev, 1);
3519 		}
3520 		break;
3521 
3522 	case NETDEV_DOWN:
3523 	case NETDEV_UNREGISTER:
3524 		/*
3525 		 *	Remove all addresses from this interface.
3526 		 */
3527 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3528 		break;
3529 
3530 	case NETDEV_CHANGENAME:
3531 		if (idev) {
3532 			snmp6_unregister_dev(idev);
3533 			addrconf_sysctl_unregister(idev);
3534 			err = addrconf_sysctl_register(idev);
3535 			if (err)
3536 				return notifier_from_errno(err);
3537 			err = snmp6_register_dev(idev);
3538 			if (err) {
3539 				addrconf_sysctl_unregister(idev);
3540 				return notifier_from_errno(err);
3541 			}
3542 		}
3543 		break;
3544 
3545 	case NETDEV_PRE_TYPE_CHANGE:
3546 	case NETDEV_POST_TYPE_CHANGE:
3547 		if (idev)
3548 			addrconf_type_change(dev, event);
3549 		break;
3550 
3551 	case NETDEV_CHANGEUPPER:
3552 		info = ptr;
3553 
3554 		/* flush all routes if dev is linked to or unlinked from
3555 		 * an L3 master device (e.g., VRF)
3556 		 */
3557 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3558 			addrconf_ifdown(dev, 0);
3559 	}
3560 
3561 	return NOTIFY_OK;
3562 }
3563 
3564 /*
3565  *	addrconf module should be notified of a device going up
3566  */
3567 static struct notifier_block ipv6_dev_notf = {
3568 	.notifier_call = addrconf_notify,
3569 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3570 };
3571 
3572 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3573 {
3574 	struct inet6_dev *idev;
3575 	ASSERT_RTNL();
3576 
3577 	idev = __in6_dev_get(dev);
3578 
3579 	if (event == NETDEV_POST_TYPE_CHANGE)
3580 		ipv6_mc_remap(idev);
3581 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3582 		ipv6_mc_unmap(idev);
3583 }
3584 
3585 static bool addr_is_local(const struct in6_addr *addr)
3586 {
3587 	return ipv6_addr_type(addr) &
3588 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3589 }
3590 
3591 static int addrconf_ifdown(struct net_device *dev, int how)
3592 {
3593 	struct net *net = dev_net(dev);
3594 	struct inet6_dev *idev;
3595 	struct inet6_ifaddr *ifa, *tmp;
3596 	struct list_head del_list;
3597 	int _keep_addr;
3598 	bool keep_addr;
3599 	int state, i;
3600 
3601 	ASSERT_RTNL();
3602 
3603 	rt6_ifdown(net, dev);
3604 	neigh_ifdown(&nd_tbl, dev);
3605 
3606 	idev = __in6_dev_get(dev);
3607 	if (!idev)
3608 		return -ENODEV;
3609 
3610 	/*
3611 	 * Step 1: remove reference to ipv6 device from parent device.
3612 	 *	   Do not dev_put!
3613 	 */
3614 	if (how) {
3615 		idev->dead = 1;
3616 
3617 		/* protected by rtnl_lock */
3618 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3619 
3620 		/* Step 1.5: remove snmp6 entry */
3621 		snmp6_unregister_dev(idev);
3622 
3623 	}
3624 
3625 	/* aggregate the system setting and interface setting */
3626 	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3627 	if (!_keep_addr)
3628 		_keep_addr = idev->cnf.keep_addr_on_down;
3629 
3630 	/* combine the user config with event to determine if permanent
3631 	 * addresses are to be removed from address hash table
3632 	 */
3633 	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
3634 
3635 	/* Step 2: clear hash table */
3636 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3637 		struct hlist_head *h = &inet6_addr_lst[i];
3638 
3639 		spin_lock_bh(&addrconf_hash_lock);
3640 restart:
3641 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3642 			if (ifa->idev == idev) {
3643 				addrconf_del_dad_work(ifa);
3644 				/* combined flag + permanent flag decide if
3645 				 * address is retained on a down event
3646 				 */
3647 				if (!keep_addr ||
3648 				    !(ifa->flags & IFA_F_PERMANENT) ||
3649 				    addr_is_local(&ifa->addr)) {
3650 					hlist_del_init_rcu(&ifa->addr_lst);
3651 					goto restart;
3652 				}
3653 			}
3654 		}
3655 		spin_unlock_bh(&addrconf_hash_lock);
3656 	}
3657 
3658 	write_lock_bh(&idev->lock);
3659 
3660 	addrconf_del_rs_timer(idev);
3661 
3662 	/* Step 2: clear flags for stateless addrconf */
3663 	if (!how)
3664 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3665 
3666 	/* Step 3: clear tempaddr list */
3667 	while (!list_empty(&idev->tempaddr_list)) {
3668 		ifa = list_first_entry(&idev->tempaddr_list,
3669 				       struct inet6_ifaddr, tmp_list);
3670 		list_del(&ifa->tmp_list);
3671 		write_unlock_bh(&idev->lock);
3672 		spin_lock_bh(&ifa->lock);
3673 
3674 		if (ifa->ifpub) {
3675 			in6_ifa_put(ifa->ifpub);
3676 			ifa->ifpub = NULL;
3677 		}
3678 		spin_unlock_bh(&ifa->lock);
3679 		in6_ifa_put(ifa);
3680 		write_lock_bh(&idev->lock);
3681 	}
3682 
3683 	/* re-combine the user config with event to determine if permanent
3684 	 * addresses are to be removed from the interface list
3685 	 */
3686 	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
3687 
3688 	INIT_LIST_HEAD(&del_list);
3689 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3690 		struct rt6_info *rt = NULL;
3691 		bool keep;
3692 
3693 		addrconf_del_dad_work(ifa);
3694 
3695 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3696 			!addr_is_local(&ifa->addr);
3697 		if (!keep)
3698 			list_move(&ifa->if_list, &del_list);
3699 
3700 		write_unlock_bh(&idev->lock);
3701 		spin_lock_bh(&ifa->lock);
3702 
3703 		if (keep) {
3704 			/* set state to skip the notifier below */
3705 			state = INET6_IFADDR_STATE_DEAD;
3706 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3707 			if (!(ifa->flags & IFA_F_NODAD))
3708 				ifa->flags |= IFA_F_TENTATIVE;
3709 
3710 			rt = ifa->rt;
3711 			ifa->rt = NULL;
3712 		} else {
3713 			state = ifa->state;
3714 			ifa->state = INET6_IFADDR_STATE_DEAD;
3715 		}
3716 
3717 		spin_unlock_bh(&ifa->lock);
3718 
3719 		if (rt)
3720 			ip6_del_rt(rt);
3721 
3722 		if (state != INET6_IFADDR_STATE_DEAD) {
3723 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3724 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3725 		} else {
3726 			if (idev->cnf.forwarding)
3727 				addrconf_leave_anycast(ifa);
3728 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3729 		}
3730 
3731 		write_lock_bh(&idev->lock);
3732 	}
3733 
3734 	write_unlock_bh(&idev->lock);
3735 
3736 	/* now clean up addresses to be removed */
3737 	while (!list_empty(&del_list)) {
3738 		ifa = list_first_entry(&del_list,
3739 				       struct inet6_ifaddr, if_list);
3740 		list_del(&ifa->if_list);
3741 
3742 		in6_ifa_put(ifa);
3743 	}
3744 
3745 	/* Step 5: Discard anycast and multicast list */
3746 	if (how) {
3747 		ipv6_ac_destroy_dev(idev);
3748 		ipv6_mc_destroy_dev(idev);
3749 	} else {
3750 		ipv6_mc_down(idev);
3751 	}
3752 
3753 	idev->tstamp = jiffies;
3754 
3755 	/* Last: Shot the device (if unregistered) */
3756 	if (how) {
3757 		addrconf_sysctl_unregister(idev);
3758 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3759 		neigh_ifdown(&nd_tbl, dev);
3760 		in6_dev_put(idev);
3761 	}
3762 	return 0;
3763 }
3764 
3765 static void addrconf_rs_timer(unsigned long data)
3766 {
3767 	struct inet6_dev *idev = (struct inet6_dev *)data;
3768 	struct net_device *dev = idev->dev;
3769 	struct in6_addr lladdr;
3770 
3771 	write_lock(&idev->lock);
3772 	if (idev->dead || !(idev->if_flags & IF_READY))
3773 		goto out;
3774 
3775 	if (!ipv6_accept_ra(idev))
3776 		goto out;
3777 
3778 	/* Announcement received after solicitation was sent */
3779 	if (idev->if_flags & IF_RA_RCVD)
3780 		goto out;
3781 
3782 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3783 		write_unlock(&idev->lock);
3784 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3785 			ndisc_send_rs(dev, &lladdr,
3786 				      &in6addr_linklocal_allrouters);
3787 		else
3788 			goto put;
3789 
3790 		write_lock(&idev->lock);
3791 		idev->rs_interval = rfc3315_s14_backoff_update(
3792 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3793 		/* The wait after the last probe can be shorter */
3794 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3795 					     idev->cnf.rtr_solicits) ?
3796 				      idev->cnf.rtr_solicit_delay :
3797 				      idev->rs_interval);
3798 	} else {
3799 		/*
3800 		 * Note: we do not support deprecated "all on-link"
3801 		 * assumption any longer.
3802 		 */
3803 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3804 	}
3805 
3806 out:
3807 	write_unlock(&idev->lock);
3808 put:
3809 	in6_dev_put(idev);
3810 }
3811 
3812 /*
3813  *	Duplicate Address Detection
3814  */
3815 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3816 {
3817 	unsigned long rand_num;
3818 	struct inet6_dev *idev = ifp->idev;
3819 	u64 nonce;
3820 
3821 	if (ifp->flags & IFA_F_OPTIMISTIC)
3822 		rand_num = 0;
3823 	else
3824 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3825 
3826 	nonce = 0;
3827 	if (idev->cnf.enhanced_dad ||
3828 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3829 		do
3830 			get_random_bytes(&nonce, 6);
3831 		while (nonce == 0);
3832 	}
3833 	ifp->dad_nonce = nonce;
3834 	ifp->dad_probes = idev->cnf.dad_transmits;
3835 	addrconf_mod_dad_work(ifp, rand_num);
3836 }
3837 
3838 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3839 {
3840 	struct inet6_dev *idev = ifp->idev;
3841 	struct net_device *dev = idev->dev;
3842 	bool bump_id, notify = false;
3843 
3844 	addrconf_join_solict(dev, &ifp->addr);
3845 
3846 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3847 
3848 	read_lock_bh(&idev->lock);
3849 	spin_lock(&ifp->lock);
3850 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3851 		goto out;
3852 
3853 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3854 	    idev->cnf.accept_dad < 1 ||
3855 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3856 	    ifp->flags & IFA_F_NODAD) {
3857 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3858 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3859 		spin_unlock(&ifp->lock);
3860 		read_unlock_bh(&idev->lock);
3861 
3862 		addrconf_dad_completed(ifp, bump_id);
3863 		return;
3864 	}
3865 
3866 	if (!(idev->if_flags & IF_READY)) {
3867 		spin_unlock(&ifp->lock);
3868 		read_unlock_bh(&idev->lock);
3869 		/*
3870 		 * If the device is not ready:
3871 		 * - keep it tentative if it is a permanent address.
3872 		 * - otherwise, kill it.
3873 		 */
3874 		in6_ifa_hold(ifp);
3875 		addrconf_dad_stop(ifp, 0);
3876 		return;
3877 	}
3878 
3879 	/*
3880 	 * Optimistic nodes can start receiving
3881 	 * Frames right away
3882 	 */
3883 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3884 		ip6_ins_rt(ifp->rt);
3885 		if (ipv6_use_optimistic_addr(idev)) {
3886 			/* Because optimistic nodes can use this address,
3887 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3888 			 */
3889 			notify = true;
3890 		}
3891 	}
3892 
3893 	addrconf_dad_kick(ifp);
3894 out:
3895 	spin_unlock(&ifp->lock);
3896 	read_unlock_bh(&idev->lock);
3897 	if (notify)
3898 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3899 }
3900 
3901 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3902 {
3903 	bool begin_dad = false;
3904 
3905 	spin_lock_bh(&ifp->lock);
3906 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3907 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3908 		begin_dad = true;
3909 	}
3910 	spin_unlock_bh(&ifp->lock);
3911 
3912 	if (begin_dad)
3913 		addrconf_mod_dad_work(ifp, 0);
3914 }
3915 
3916 static void addrconf_dad_work(struct work_struct *w)
3917 {
3918 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3919 						struct inet6_ifaddr,
3920 						dad_work);
3921 	struct inet6_dev *idev = ifp->idev;
3922 	bool bump_id, disable_ipv6 = false;
3923 	struct in6_addr mcaddr;
3924 
3925 	enum {
3926 		DAD_PROCESS,
3927 		DAD_BEGIN,
3928 		DAD_ABORT,
3929 	} action = DAD_PROCESS;
3930 
3931 	rtnl_lock();
3932 
3933 	spin_lock_bh(&ifp->lock);
3934 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3935 		action = DAD_BEGIN;
3936 		ifp->state = INET6_IFADDR_STATE_DAD;
3937 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3938 		action = DAD_ABORT;
3939 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3940 
3941 		if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6 &&
3942 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3943 			struct in6_addr addr;
3944 
3945 			addr.s6_addr32[0] = htonl(0xfe800000);
3946 			addr.s6_addr32[1] = 0;
3947 
3948 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3949 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3950 				/* DAD failed for link-local based on MAC */
3951 				idev->cnf.disable_ipv6 = 1;
3952 
3953 				pr_info("%s: IPv6 being disabled!\n",
3954 					ifp->idev->dev->name);
3955 				disable_ipv6 = true;
3956 			}
3957 		}
3958 	}
3959 	spin_unlock_bh(&ifp->lock);
3960 
3961 	if (action == DAD_BEGIN) {
3962 		addrconf_dad_begin(ifp);
3963 		goto out;
3964 	} else if (action == DAD_ABORT) {
3965 		in6_ifa_hold(ifp);
3966 		addrconf_dad_stop(ifp, 1);
3967 		if (disable_ipv6)
3968 			addrconf_ifdown(idev->dev, 0);
3969 		goto out;
3970 	}
3971 
3972 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3973 		goto out;
3974 
3975 	write_lock_bh(&idev->lock);
3976 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3977 		write_unlock_bh(&idev->lock);
3978 		goto out;
3979 	}
3980 
3981 	spin_lock(&ifp->lock);
3982 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3983 		spin_unlock(&ifp->lock);
3984 		write_unlock_bh(&idev->lock);
3985 		goto out;
3986 	}
3987 
3988 	if (ifp->dad_probes == 0) {
3989 		/*
3990 		 * DAD was successful
3991 		 */
3992 
3993 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3994 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3995 		spin_unlock(&ifp->lock);
3996 		write_unlock_bh(&idev->lock);
3997 
3998 		addrconf_dad_completed(ifp, bump_id);
3999 
4000 		goto out;
4001 	}
4002 
4003 	ifp->dad_probes--;
4004 	addrconf_mod_dad_work(ifp,
4005 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4006 	spin_unlock(&ifp->lock);
4007 	write_unlock_bh(&idev->lock);
4008 
4009 	/* send a neighbour solicitation for our addr */
4010 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4011 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4012 		      ifp->dad_nonce);
4013 out:
4014 	in6_ifa_put(ifp);
4015 	rtnl_unlock();
4016 }
4017 
4018 /* ifp->idev must be at least read locked */
4019 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4020 {
4021 	struct inet6_ifaddr *ifpiter;
4022 	struct inet6_dev *idev = ifp->idev;
4023 
4024 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4025 		if (ifpiter->scope > IFA_LINK)
4026 			break;
4027 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4028 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4029 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4030 		    IFA_F_PERMANENT)
4031 			return false;
4032 	}
4033 	return true;
4034 }
4035 
4036 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id)
4037 {
4038 	struct net_device *dev = ifp->idev->dev;
4039 	struct in6_addr lladdr;
4040 	bool send_rs, send_mld;
4041 
4042 	addrconf_del_dad_work(ifp);
4043 
4044 	/*
4045 	 *	Configure the address for reception. Now it is valid.
4046 	 */
4047 
4048 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4049 
4050 	/* If added prefix is link local and we are prepared to process
4051 	   router advertisements, start sending router solicitations.
4052 	 */
4053 
4054 	read_lock_bh(&ifp->idev->lock);
4055 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4056 	send_rs = send_mld &&
4057 		  ipv6_accept_ra(ifp->idev) &&
4058 		  ifp->idev->cnf.rtr_solicits != 0 &&
4059 		  (dev->flags&IFF_LOOPBACK) == 0;
4060 	read_unlock_bh(&ifp->idev->lock);
4061 
4062 	/* While dad is in progress mld report's source address is in6_addrany.
4063 	 * Resend with proper ll now.
4064 	 */
4065 	if (send_mld)
4066 		ipv6_mc_dad_complete(ifp->idev);
4067 
4068 	if (send_rs) {
4069 		/*
4070 		 *	If a host as already performed a random delay
4071 		 *	[...] as part of DAD [...] there is no need
4072 		 *	to delay again before sending the first RS
4073 		 */
4074 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4075 			return;
4076 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4077 
4078 		write_lock_bh(&ifp->idev->lock);
4079 		spin_lock(&ifp->lock);
4080 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4081 			ifp->idev->cnf.rtr_solicit_interval);
4082 		ifp->idev->rs_probes = 1;
4083 		ifp->idev->if_flags |= IF_RS_SENT;
4084 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4085 		spin_unlock(&ifp->lock);
4086 		write_unlock_bh(&ifp->idev->lock);
4087 	}
4088 
4089 	if (bump_id)
4090 		rt_genid_bump_ipv6(dev_net(dev));
4091 
4092 	/* Make sure that a new temporary address will be created
4093 	 * before this temporary address becomes deprecated.
4094 	 */
4095 	if (ifp->flags & IFA_F_TEMPORARY)
4096 		addrconf_verify_rtnl();
4097 }
4098 
4099 static void addrconf_dad_run(struct inet6_dev *idev)
4100 {
4101 	struct inet6_ifaddr *ifp;
4102 
4103 	read_lock_bh(&idev->lock);
4104 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4105 		spin_lock(&ifp->lock);
4106 		if (ifp->flags & IFA_F_TENTATIVE &&
4107 		    ifp->state == INET6_IFADDR_STATE_DAD)
4108 			addrconf_dad_kick(ifp);
4109 		spin_unlock(&ifp->lock);
4110 	}
4111 	read_unlock_bh(&idev->lock);
4112 }
4113 
4114 #ifdef CONFIG_PROC_FS
4115 struct if6_iter_state {
4116 	struct seq_net_private p;
4117 	int bucket;
4118 	int offset;
4119 };
4120 
4121 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4122 {
4123 	struct inet6_ifaddr *ifa = NULL;
4124 	struct if6_iter_state *state = seq->private;
4125 	struct net *net = seq_file_net(seq);
4126 	int p = 0;
4127 
4128 	/* initial bucket if pos is 0 */
4129 	if (pos == 0) {
4130 		state->bucket = 0;
4131 		state->offset = 0;
4132 	}
4133 
4134 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4135 		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
4136 					 addr_lst) {
4137 			if (!net_eq(dev_net(ifa->idev->dev), net))
4138 				continue;
4139 			/* sync with offset */
4140 			if (p < state->offset) {
4141 				p++;
4142 				continue;
4143 			}
4144 			state->offset++;
4145 			return ifa;
4146 		}
4147 
4148 		/* prepare for next bucket */
4149 		state->offset = 0;
4150 		p = 0;
4151 	}
4152 	return NULL;
4153 }
4154 
4155 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4156 					 struct inet6_ifaddr *ifa)
4157 {
4158 	struct if6_iter_state *state = seq->private;
4159 	struct net *net = seq_file_net(seq);
4160 
4161 	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
4162 		if (!net_eq(dev_net(ifa->idev->dev), net))
4163 			continue;
4164 		state->offset++;
4165 		return ifa;
4166 	}
4167 
4168 	while (++state->bucket < IN6_ADDR_HSIZE) {
4169 		state->offset = 0;
4170 		hlist_for_each_entry_rcu_bh(ifa,
4171 				     &inet6_addr_lst[state->bucket], addr_lst) {
4172 			if (!net_eq(dev_net(ifa->idev->dev), net))
4173 				continue;
4174 			state->offset++;
4175 			return ifa;
4176 		}
4177 	}
4178 
4179 	return NULL;
4180 }
4181 
4182 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4183 	__acquires(rcu_bh)
4184 {
4185 	rcu_read_lock_bh();
4186 	return if6_get_first(seq, *pos);
4187 }
4188 
4189 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4190 {
4191 	struct inet6_ifaddr *ifa;
4192 
4193 	ifa = if6_get_next(seq, v);
4194 	++*pos;
4195 	return ifa;
4196 }
4197 
4198 static void if6_seq_stop(struct seq_file *seq, void *v)
4199 	__releases(rcu_bh)
4200 {
4201 	rcu_read_unlock_bh();
4202 }
4203 
4204 static int if6_seq_show(struct seq_file *seq, void *v)
4205 {
4206 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4207 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4208 		   &ifp->addr,
4209 		   ifp->idev->dev->ifindex,
4210 		   ifp->prefix_len,
4211 		   ifp->scope,
4212 		   (u8) ifp->flags,
4213 		   ifp->idev->dev->name);
4214 	return 0;
4215 }
4216 
4217 static const struct seq_operations if6_seq_ops = {
4218 	.start	= if6_seq_start,
4219 	.next	= if6_seq_next,
4220 	.show	= if6_seq_show,
4221 	.stop	= if6_seq_stop,
4222 };
4223 
4224 static int if6_seq_open(struct inode *inode, struct file *file)
4225 {
4226 	return seq_open_net(inode, file, &if6_seq_ops,
4227 			    sizeof(struct if6_iter_state));
4228 }
4229 
4230 static const struct file_operations if6_fops = {
4231 	.owner		= THIS_MODULE,
4232 	.open		= if6_seq_open,
4233 	.read		= seq_read,
4234 	.llseek		= seq_lseek,
4235 	.release	= seq_release_net,
4236 };
4237 
4238 static int __net_init if6_proc_net_init(struct net *net)
4239 {
4240 	if (!proc_create("if_inet6", S_IRUGO, net->proc_net, &if6_fops))
4241 		return -ENOMEM;
4242 	return 0;
4243 }
4244 
4245 static void __net_exit if6_proc_net_exit(struct net *net)
4246 {
4247 	remove_proc_entry("if_inet6", net->proc_net);
4248 }
4249 
4250 static struct pernet_operations if6_proc_net_ops = {
4251 	.init = if6_proc_net_init,
4252 	.exit = if6_proc_net_exit,
4253 };
4254 
4255 int __init if6_proc_init(void)
4256 {
4257 	return register_pernet_subsys(&if6_proc_net_ops);
4258 }
4259 
4260 void if6_proc_exit(void)
4261 {
4262 	unregister_pernet_subsys(&if6_proc_net_ops);
4263 }
4264 #endif	/* CONFIG_PROC_FS */
4265 
4266 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4267 /* Check if address is a home address configured on any interface. */
4268 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4269 {
4270 	int ret = 0;
4271 	struct inet6_ifaddr *ifp = NULL;
4272 	unsigned int hash = inet6_addr_hash(addr);
4273 
4274 	rcu_read_lock_bh();
4275 	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
4276 		if (!net_eq(dev_net(ifp->idev->dev), net))
4277 			continue;
4278 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4279 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4280 			ret = 1;
4281 			break;
4282 		}
4283 	}
4284 	rcu_read_unlock_bh();
4285 	return ret;
4286 }
4287 #endif
4288 
4289 /*
4290  *	Periodic address status verification
4291  */
4292 
4293 static void addrconf_verify_rtnl(void)
4294 {
4295 	unsigned long now, next, next_sec, next_sched;
4296 	struct inet6_ifaddr *ifp;
4297 	int i;
4298 
4299 	ASSERT_RTNL();
4300 
4301 	rcu_read_lock_bh();
4302 	now = jiffies;
4303 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4304 
4305 	cancel_delayed_work(&addr_chk_work);
4306 
4307 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4308 restart:
4309 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4310 			unsigned long age;
4311 
4312 			/* When setting preferred_lft to a value not zero or
4313 			 * infinity, while valid_lft is infinity
4314 			 * IFA_F_PERMANENT has a non-infinity life time.
4315 			 */
4316 			if ((ifp->flags & IFA_F_PERMANENT) &&
4317 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4318 				continue;
4319 
4320 			spin_lock(&ifp->lock);
4321 			/* We try to batch several events at once. */
4322 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4323 
4324 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4325 			    age >= ifp->valid_lft) {
4326 				spin_unlock(&ifp->lock);
4327 				in6_ifa_hold(ifp);
4328 				ipv6_del_addr(ifp);
4329 				goto restart;
4330 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4331 				spin_unlock(&ifp->lock);
4332 				continue;
4333 			} else if (age >= ifp->prefered_lft) {
4334 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4335 				int deprecate = 0;
4336 
4337 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4338 					deprecate = 1;
4339 					ifp->flags |= IFA_F_DEPRECATED;
4340 				}
4341 
4342 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4343 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4344 					next = ifp->tstamp + ifp->valid_lft * HZ;
4345 
4346 				spin_unlock(&ifp->lock);
4347 
4348 				if (deprecate) {
4349 					in6_ifa_hold(ifp);
4350 
4351 					ipv6_ifa_notify(0, ifp);
4352 					in6_ifa_put(ifp);
4353 					goto restart;
4354 				}
4355 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4356 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4357 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4358 					ifp->idev->cnf.dad_transmits *
4359 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4360 
4361 				if (age >= ifp->prefered_lft - regen_advance) {
4362 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4363 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4364 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4365 					if (!ifp->regen_count && ifpub) {
4366 						ifp->regen_count++;
4367 						in6_ifa_hold(ifp);
4368 						in6_ifa_hold(ifpub);
4369 						spin_unlock(&ifp->lock);
4370 
4371 						spin_lock(&ifpub->lock);
4372 						ifpub->regen_count = 0;
4373 						spin_unlock(&ifpub->lock);
4374 						ipv6_create_tempaddr(ifpub, ifp);
4375 						in6_ifa_put(ifpub);
4376 						in6_ifa_put(ifp);
4377 						goto restart;
4378 					}
4379 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4380 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4381 				spin_unlock(&ifp->lock);
4382 			} else {
4383 				/* ifp->prefered_lft <= ifp->valid_lft */
4384 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4385 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4386 				spin_unlock(&ifp->lock);
4387 			}
4388 		}
4389 	}
4390 
4391 	next_sec = round_jiffies_up(next);
4392 	next_sched = next;
4393 
4394 	/* If rounded timeout is accurate enough, accept it. */
4395 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4396 		next_sched = next_sec;
4397 
4398 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4399 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4400 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4401 
4402 	ADBG(KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4403 	      now, next, next_sec, next_sched);
4404 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4405 	rcu_read_unlock_bh();
4406 }
4407 
4408 static void addrconf_verify_work(struct work_struct *w)
4409 {
4410 	rtnl_lock();
4411 	addrconf_verify_rtnl();
4412 	rtnl_unlock();
4413 }
4414 
4415 static void addrconf_verify(void)
4416 {
4417 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4418 }
4419 
4420 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4421 				     struct in6_addr **peer_pfx)
4422 {
4423 	struct in6_addr *pfx = NULL;
4424 
4425 	*peer_pfx = NULL;
4426 
4427 	if (addr)
4428 		pfx = nla_data(addr);
4429 
4430 	if (local) {
4431 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4432 			*peer_pfx = pfx;
4433 		pfx = nla_data(local);
4434 	}
4435 
4436 	return pfx;
4437 }
4438 
4439 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4440 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4441 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4442 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4443 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4444 };
4445 
4446 static int
4447 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4448 		  struct netlink_ext_ack *extack)
4449 {
4450 	struct net *net = sock_net(skb->sk);
4451 	struct ifaddrmsg *ifm;
4452 	struct nlattr *tb[IFA_MAX+1];
4453 	struct in6_addr *pfx, *peer_pfx;
4454 	u32 ifa_flags;
4455 	int err;
4456 
4457 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4458 			  extack);
4459 	if (err < 0)
4460 		return err;
4461 
4462 	ifm = nlmsg_data(nlh);
4463 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4464 	if (!pfx)
4465 		return -EINVAL;
4466 
4467 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4468 
4469 	/* We ignore other flags so far. */
4470 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4471 
4472 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4473 			      ifm->ifa_prefixlen);
4474 }
4475 
4476 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4477 			     u32 prefered_lft, u32 valid_lft)
4478 {
4479 	u32 flags;
4480 	clock_t expires;
4481 	unsigned long timeout;
4482 	bool was_managetempaddr;
4483 	bool had_prefixroute;
4484 
4485 	ASSERT_RTNL();
4486 
4487 	if (!valid_lft || (prefered_lft > valid_lft))
4488 		return -EINVAL;
4489 
4490 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4491 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4492 		return -EINVAL;
4493 
4494 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4495 	if (addrconf_finite_timeout(timeout)) {
4496 		expires = jiffies_to_clock_t(timeout * HZ);
4497 		valid_lft = timeout;
4498 		flags = RTF_EXPIRES;
4499 	} else {
4500 		expires = 0;
4501 		flags = 0;
4502 		ifa_flags |= IFA_F_PERMANENT;
4503 	}
4504 
4505 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4506 	if (addrconf_finite_timeout(timeout)) {
4507 		if (timeout == 0)
4508 			ifa_flags |= IFA_F_DEPRECATED;
4509 		prefered_lft = timeout;
4510 	}
4511 
4512 	spin_lock_bh(&ifp->lock);
4513 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4514 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4515 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4516 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4517 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4518 			IFA_F_NOPREFIXROUTE);
4519 	ifp->flags |= ifa_flags;
4520 	ifp->tstamp = jiffies;
4521 	ifp->valid_lft = valid_lft;
4522 	ifp->prefered_lft = prefered_lft;
4523 
4524 	spin_unlock_bh(&ifp->lock);
4525 	if (!(ifp->flags&IFA_F_TENTATIVE))
4526 		ipv6_ifa_notify(0, ifp);
4527 
4528 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4529 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
4530 				      expires, flags);
4531 	} else if (had_prefixroute) {
4532 		enum cleanup_prefix_rt_t action;
4533 		unsigned long rt_expires;
4534 
4535 		write_lock_bh(&ifp->idev->lock);
4536 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4537 		write_unlock_bh(&ifp->idev->lock);
4538 
4539 		if (action != CLEANUP_PREFIX_RT_NOP) {
4540 			cleanup_prefix_route(ifp, rt_expires,
4541 				action == CLEANUP_PREFIX_RT_DEL);
4542 		}
4543 	}
4544 
4545 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4546 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4547 			valid_lft = prefered_lft = 0;
4548 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4549 				 !was_managetempaddr, jiffies);
4550 	}
4551 
4552 	addrconf_verify_rtnl();
4553 
4554 	return 0;
4555 }
4556 
4557 static int
4558 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4559 		  struct netlink_ext_ack *extack)
4560 {
4561 	struct net *net = sock_net(skb->sk);
4562 	struct ifaddrmsg *ifm;
4563 	struct nlattr *tb[IFA_MAX+1];
4564 	struct in6_addr *pfx, *peer_pfx;
4565 	struct inet6_ifaddr *ifa;
4566 	struct net_device *dev;
4567 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4568 	u32 ifa_flags;
4569 	int err;
4570 
4571 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4572 			  extack);
4573 	if (err < 0)
4574 		return err;
4575 
4576 	ifm = nlmsg_data(nlh);
4577 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4578 	if (!pfx)
4579 		return -EINVAL;
4580 
4581 	if (tb[IFA_CACHEINFO]) {
4582 		struct ifa_cacheinfo *ci;
4583 
4584 		ci = nla_data(tb[IFA_CACHEINFO]);
4585 		valid_lft = ci->ifa_valid;
4586 		preferred_lft = ci->ifa_prefered;
4587 	} else {
4588 		preferred_lft = INFINITY_LIFE_TIME;
4589 		valid_lft = INFINITY_LIFE_TIME;
4590 	}
4591 
4592 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4593 	if (!dev)
4594 		return -ENODEV;
4595 
4596 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4597 
4598 	/* We ignore other flags so far. */
4599 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4600 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN;
4601 
4602 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4603 	if (!ifa) {
4604 		/*
4605 		 * It would be best to check for !NLM_F_CREATE here but
4606 		 * userspace already relies on not having to provide this.
4607 		 */
4608 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4609 				      ifm->ifa_prefixlen, ifa_flags,
4610 				      preferred_lft, valid_lft);
4611 	}
4612 
4613 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4614 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4615 		err = -EEXIST;
4616 	else
4617 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4618 
4619 	in6_ifa_put(ifa);
4620 
4621 	return err;
4622 }
4623 
4624 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4625 			  u8 scope, int ifindex)
4626 {
4627 	struct ifaddrmsg *ifm;
4628 
4629 	ifm = nlmsg_data(nlh);
4630 	ifm->ifa_family = AF_INET6;
4631 	ifm->ifa_prefixlen = prefixlen;
4632 	ifm->ifa_flags = flags;
4633 	ifm->ifa_scope = scope;
4634 	ifm->ifa_index = ifindex;
4635 }
4636 
4637 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4638 			 unsigned long tstamp, u32 preferred, u32 valid)
4639 {
4640 	struct ifa_cacheinfo ci;
4641 
4642 	ci.cstamp = cstamp_delta(cstamp);
4643 	ci.tstamp = cstamp_delta(tstamp);
4644 	ci.ifa_prefered = preferred;
4645 	ci.ifa_valid = valid;
4646 
4647 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4648 }
4649 
4650 static inline int rt_scope(int ifa_scope)
4651 {
4652 	if (ifa_scope & IFA_HOST)
4653 		return RT_SCOPE_HOST;
4654 	else if (ifa_scope & IFA_LINK)
4655 		return RT_SCOPE_LINK;
4656 	else if (ifa_scope & IFA_SITE)
4657 		return RT_SCOPE_SITE;
4658 	else
4659 		return RT_SCOPE_UNIVERSE;
4660 }
4661 
4662 static inline int inet6_ifaddr_msgsize(void)
4663 {
4664 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4665 	       + nla_total_size(16) /* IFA_LOCAL */
4666 	       + nla_total_size(16) /* IFA_ADDRESS */
4667 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4668 	       + nla_total_size(4)  /* IFA_FLAGS */;
4669 }
4670 
4671 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4672 			     u32 portid, u32 seq, int event, unsigned int flags)
4673 {
4674 	struct nlmsghdr  *nlh;
4675 	u32 preferred, valid;
4676 
4677 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4678 	if (!nlh)
4679 		return -EMSGSIZE;
4680 
4681 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4682 		      ifa->idev->dev->ifindex);
4683 
4684 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4685 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4686 		preferred = ifa->prefered_lft;
4687 		valid = ifa->valid_lft;
4688 		if (preferred != INFINITY_LIFE_TIME) {
4689 			long tval = (jiffies - ifa->tstamp)/HZ;
4690 			if (preferred > tval)
4691 				preferred -= tval;
4692 			else
4693 				preferred = 0;
4694 			if (valid != INFINITY_LIFE_TIME) {
4695 				if (valid > tval)
4696 					valid -= tval;
4697 				else
4698 					valid = 0;
4699 			}
4700 		}
4701 	} else {
4702 		preferred = INFINITY_LIFE_TIME;
4703 		valid = INFINITY_LIFE_TIME;
4704 	}
4705 
4706 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4707 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4708 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4709 			goto error;
4710 	} else
4711 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4712 			goto error;
4713 
4714 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4715 		goto error;
4716 
4717 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4718 		goto error;
4719 
4720 	nlmsg_end(skb, nlh);
4721 	return 0;
4722 
4723 error:
4724 	nlmsg_cancel(skb, nlh);
4725 	return -EMSGSIZE;
4726 }
4727 
4728 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4729 				u32 portid, u32 seq, int event, u16 flags)
4730 {
4731 	struct nlmsghdr  *nlh;
4732 	u8 scope = RT_SCOPE_UNIVERSE;
4733 	int ifindex = ifmca->idev->dev->ifindex;
4734 
4735 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4736 		scope = RT_SCOPE_SITE;
4737 
4738 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4739 	if (!nlh)
4740 		return -EMSGSIZE;
4741 
4742 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4743 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4744 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4745 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4746 		nlmsg_cancel(skb, nlh);
4747 		return -EMSGSIZE;
4748 	}
4749 
4750 	nlmsg_end(skb, nlh);
4751 	return 0;
4752 }
4753 
4754 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4755 				u32 portid, u32 seq, int event, unsigned int flags)
4756 {
4757 	struct nlmsghdr  *nlh;
4758 	u8 scope = RT_SCOPE_UNIVERSE;
4759 	int ifindex = ifaca->aca_idev->dev->ifindex;
4760 
4761 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4762 		scope = RT_SCOPE_SITE;
4763 
4764 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4765 	if (!nlh)
4766 		return -EMSGSIZE;
4767 
4768 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4769 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4770 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4771 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4772 		nlmsg_cancel(skb, nlh);
4773 		return -EMSGSIZE;
4774 	}
4775 
4776 	nlmsg_end(skb, nlh);
4777 	return 0;
4778 }
4779 
4780 enum addr_type_t {
4781 	UNICAST_ADDR,
4782 	MULTICAST_ADDR,
4783 	ANYCAST_ADDR,
4784 };
4785 
4786 /* called with rcu_read_lock() */
4787 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4788 			  struct netlink_callback *cb, enum addr_type_t type,
4789 			  int s_ip_idx, int *p_ip_idx)
4790 {
4791 	struct ifmcaddr6 *ifmca;
4792 	struct ifacaddr6 *ifaca;
4793 	int err = 1;
4794 	int ip_idx = *p_ip_idx;
4795 
4796 	read_lock_bh(&idev->lock);
4797 	switch (type) {
4798 	case UNICAST_ADDR: {
4799 		struct inet6_ifaddr *ifa;
4800 
4801 		/* unicast address incl. temp addr */
4802 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4803 			if (++ip_idx < s_ip_idx)
4804 				continue;
4805 			err = inet6_fill_ifaddr(skb, ifa,
4806 						NETLINK_CB(cb->skb).portid,
4807 						cb->nlh->nlmsg_seq,
4808 						RTM_NEWADDR,
4809 						NLM_F_MULTI);
4810 			if (err < 0)
4811 				break;
4812 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4813 		}
4814 		break;
4815 	}
4816 	case MULTICAST_ADDR:
4817 		/* multicast address */
4818 		for (ifmca = idev->mc_list; ifmca;
4819 		     ifmca = ifmca->next, ip_idx++) {
4820 			if (ip_idx < s_ip_idx)
4821 				continue;
4822 			err = inet6_fill_ifmcaddr(skb, ifmca,
4823 						  NETLINK_CB(cb->skb).portid,
4824 						  cb->nlh->nlmsg_seq,
4825 						  RTM_GETMULTICAST,
4826 						  NLM_F_MULTI);
4827 			if (err < 0)
4828 				break;
4829 		}
4830 		break;
4831 	case ANYCAST_ADDR:
4832 		/* anycast address */
4833 		for (ifaca = idev->ac_list; ifaca;
4834 		     ifaca = ifaca->aca_next, ip_idx++) {
4835 			if (ip_idx < s_ip_idx)
4836 				continue;
4837 			err = inet6_fill_ifacaddr(skb, ifaca,
4838 						  NETLINK_CB(cb->skb).portid,
4839 						  cb->nlh->nlmsg_seq,
4840 						  RTM_GETANYCAST,
4841 						  NLM_F_MULTI);
4842 			if (err < 0)
4843 				break;
4844 		}
4845 		break;
4846 	default:
4847 		break;
4848 	}
4849 	read_unlock_bh(&idev->lock);
4850 	*p_ip_idx = ip_idx;
4851 	return err;
4852 }
4853 
4854 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4855 			   enum addr_type_t type)
4856 {
4857 	struct net *net = sock_net(skb->sk);
4858 	int h, s_h;
4859 	int idx, ip_idx;
4860 	int s_idx, s_ip_idx;
4861 	struct net_device *dev;
4862 	struct inet6_dev *idev;
4863 	struct hlist_head *head;
4864 
4865 	s_h = cb->args[0];
4866 	s_idx = idx = cb->args[1];
4867 	s_ip_idx = ip_idx = cb->args[2];
4868 
4869 	rcu_read_lock();
4870 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4871 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4872 		idx = 0;
4873 		head = &net->dev_index_head[h];
4874 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4875 			if (idx < s_idx)
4876 				goto cont;
4877 			if (h > s_h || idx > s_idx)
4878 				s_ip_idx = 0;
4879 			ip_idx = 0;
4880 			idev = __in6_dev_get(dev);
4881 			if (!idev)
4882 				goto cont;
4883 
4884 			if (in6_dump_addrs(idev, skb, cb, type,
4885 					   s_ip_idx, &ip_idx) < 0)
4886 				goto done;
4887 cont:
4888 			idx++;
4889 		}
4890 	}
4891 done:
4892 	rcu_read_unlock();
4893 	cb->args[0] = h;
4894 	cb->args[1] = idx;
4895 	cb->args[2] = ip_idx;
4896 
4897 	return skb->len;
4898 }
4899 
4900 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4901 {
4902 	enum addr_type_t type = UNICAST_ADDR;
4903 
4904 	return inet6_dump_addr(skb, cb, type);
4905 }
4906 
4907 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4908 {
4909 	enum addr_type_t type = MULTICAST_ADDR;
4910 
4911 	return inet6_dump_addr(skb, cb, type);
4912 }
4913 
4914 
4915 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4916 {
4917 	enum addr_type_t type = ANYCAST_ADDR;
4918 
4919 	return inet6_dump_addr(skb, cb, type);
4920 }
4921 
4922 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4923 			     struct netlink_ext_ack *extack)
4924 {
4925 	struct net *net = sock_net(in_skb->sk);
4926 	struct ifaddrmsg *ifm;
4927 	struct nlattr *tb[IFA_MAX+1];
4928 	struct in6_addr *addr = NULL, *peer;
4929 	struct net_device *dev = NULL;
4930 	struct inet6_ifaddr *ifa;
4931 	struct sk_buff *skb;
4932 	int err;
4933 
4934 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4935 			  extack);
4936 	if (err < 0)
4937 		goto errout;
4938 
4939 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
4940 	if (!addr) {
4941 		err = -EINVAL;
4942 		goto errout;
4943 	}
4944 
4945 	ifm = nlmsg_data(nlh);
4946 	if (ifm->ifa_index)
4947 		dev = __dev_get_by_index(net, ifm->ifa_index);
4948 
4949 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
4950 	if (!ifa) {
4951 		err = -EADDRNOTAVAIL;
4952 		goto errout;
4953 	}
4954 
4955 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
4956 	if (!skb) {
4957 		err = -ENOBUFS;
4958 		goto errout_ifa;
4959 	}
4960 
4961 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
4962 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
4963 	if (err < 0) {
4964 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4965 		WARN_ON(err == -EMSGSIZE);
4966 		kfree_skb(skb);
4967 		goto errout_ifa;
4968 	}
4969 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
4970 errout_ifa:
4971 	in6_ifa_put(ifa);
4972 errout:
4973 	return err;
4974 }
4975 
4976 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
4977 {
4978 	struct sk_buff *skb;
4979 	struct net *net = dev_net(ifa->idev->dev);
4980 	int err = -ENOBUFS;
4981 
4982 	/* Don't send DELADDR notification for TENTATIVE address,
4983 	 * since NEWADDR notification is sent only after removing
4984 	 * TENTATIVE flag.
4985 	 */
4986 	if (ifa->flags & IFA_F_TENTATIVE && event == RTM_DELADDR)
4987 		return;
4988 
4989 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
4990 	if (!skb)
4991 		goto errout;
4992 
4993 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
4994 	if (err < 0) {
4995 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
4996 		WARN_ON(err == -EMSGSIZE);
4997 		kfree_skb(skb);
4998 		goto errout;
4999 	}
5000 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5001 	return;
5002 errout:
5003 	if (err < 0)
5004 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5005 }
5006 
5007 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5008 				__s32 *array, int bytes)
5009 {
5010 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5011 
5012 	memset(array, 0, bytes);
5013 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5014 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5015 	array[DEVCONF_MTU6] = cnf->mtu6;
5016 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5017 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5018 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5019 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5020 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5021 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5022 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5023 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5024 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5025 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5026 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5027 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5028 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5029 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5030 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5031 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5032 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5033 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5034 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5035 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5036 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5037 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5038 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5039 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5040 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5041 #ifdef CONFIG_IPV6_ROUTER_PREF
5042 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5043 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5044 		jiffies_to_msecs(cnf->rtr_probe_interval);
5045 #ifdef CONFIG_IPV6_ROUTE_INFO
5046 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5047 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5048 #endif
5049 #endif
5050 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5051 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5052 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5053 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5054 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5055 #endif
5056 #ifdef CONFIG_IPV6_MROUTE
5057 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5058 #endif
5059 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5060 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5061 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5062 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5063 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5064 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5065 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5066 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5067 	/* we omit DEVCONF_STABLE_SECRET for now */
5068 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5069 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5070 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5071 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5072 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5073 #ifdef CONFIG_IPV6_SEG6_HMAC
5074 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5075 #endif
5076 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5077 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5078 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5079 }
5080 
5081 static inline size_t inet6_ifla6_size(void)
5082 {
5083 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5084 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5085 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5086 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5087 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5088 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5089 }
5090 
5091 static inline size_t inet6_if_nlmsg_size(void)
5092 {
5093 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5094 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5095 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5096 	       + nla_total_size(4) /* IFLA_MTU */
5097 	       + nla_total_size(4) /* IFLA_LINK */
5098 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5099 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5100 }
5101 
5102 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5103 					int bytes)
5104 {
5105 	int i;
5106 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5107 	BUG_ON(pad < 0);
5108 
5109 	/* Use put_unaligned() because stats may not be aligned for u64. */
5110 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5111 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5112 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5113 
5114 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5115 }
5116 
5117 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5118 					int bytes, size_t syncpoff)
5119 {
5120 	int i, c;
5121 	u64 buff[IPSTATS_MIB_MAX];
5122 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5123 
5124 	BUG_ON(pad < 0);
5125 
5126 	memset(buff, 0, sizeof(buff));
5127 	buff[0] = IPSTATS_MIB_MAX;
5128 
5129 	for_each_possible_cpu(c) {
5130 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5131 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5132 	}
5133 
5134 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5135 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5136 }
5137 
5138 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5139 			     int bytes)
5140 {
5141 	switch (attrtype) {
5142 	case IFLA_INET6_STATS:
5143 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5144 				     offsetof(struct ipstats_mib, syncp));
5145 		break;
5146 	case IFLA_INET6_ICMP6STATS:
5147 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5148 		break;
5149 	}
5150 }
5151 
5152 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5153 				  u32 ext_filter_mask)
5154 {
5155 	struct nlattr *nla;
5156 	struct ifla_cacheinfo ci;
5157 
5158 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5159 		goto nla_put_failure;
5160 	ci.max_reasm_len = IPV6_MAXPLEN;
5161 	ci.tstamp = cstamp_delta(idev->tstamp);
5162 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5163 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5164 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5165 		goto nla_put_failure;
5166 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5167 	if (!nla)
5168 		goto nla_put_failure;
5169 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5170 
5171 	/* XXX - MC not implemented */
5172 
5173 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5174 		return 0;
5175 
5176 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5177 	if (!nla)
5178 		goto nla_put_failure;
5179 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5180 
5181 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5182 	if (!nla)
5183 		goto nla_put_failure;
5184 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5185 
5186 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5187 	if (!nla)
5188 		goto nla_put_failure;
5189 
5190 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5191 		goto nla_put_failure;
5192 
5193 	read_lock_bh(&idev->lock);
5194 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5195 	read_unlock_bh(&idev->lock);
5196 
5197 	return 0;
5198 
5199 nla_put_failure:
5200 	return -EMSGSIZE;
5201 }
5202 
5203 static size_t inet6_get_link_af_size(const struct net_device *dev,
5204 				     u32 ext_filter_mask)
5205 {
5206 	if (!__in6_dev_get(dev))
5207 		return 0;
5208 
5209 	return inet6_ifla6_size();
5210 }
5211 
5212 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5213 			      u32 ext_filter_mask)
5214 {
5215 	struct inet6_dev *idev = __in6_dev_get(dev);
5216 
5217 	if (!idev)
5218 		return -ENODATA;
5219 
5220 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5221 		return -EMSGSIZE;
5222 
5223 	return 0;
5224 }
5225 
5226 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5227 {
5228 	struct inet6_ifaddr *ifp;
5229 	struct net_device *dev = idev->dev;
5230 	bool clear_token, update_rs = false;
5231 	struct in6_addr ll_addr;
5232 
5233 	ASSERT_RTNL();
5234 
5235 	if (!token)
5236 		return -EINVAL;
5237 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5238 		return -EINVAL;
5239 	if (!ipv6_accept_ra(idev))
5240 		return -EINVAL;
5241 	if (idev->cnf.rtr_solicits == 0)
5242 		return -EINVAL;
5243 
5244 	write_lock_bh(&idev->lock);
5245 
5246 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5247 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5248 
5249 	write_unlock_bh(&idev->lock);
5250 
5251 	clear_token = ipv6_addr_any(token);
5252 	if (clear_token)
5253 		goto update_lft;
5254 
5255 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5256 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5257 			     IFA_F_OPTIMISTIC)) {
5258 		/* If we're not ready, then normal ifup will take care
5259 		 * of this. Otherwise, we need to request our rs here.
5260 		 */
5261 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5262 		update_rs = true;
5263 	}
5264 
5265 update_lft:
5266 	write_lock_bh(&idev->lock);
5267 
5268 	if (update_rs) {
5269 		idev->if_flags |= IF_RS_SENT;
5270 		idev->rs_interval = rfc3315_s14_backoff_init(
5271 			idev->cnf.rtr_solicit_interval);
5272 		idev->rs_probes = 1;
5273 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5274 	}
5275 
5276 	/* Well, that's kinda nasty ... */
5277 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5278 		spin_lock(&ifp->lock);
5279 		if (ifp->tokenized) {
5280 			ifp->valid_lft = 0;
5281 			ifp->prefered_lft = 0;
5282 		}
5283 		spin_unlock(&ifp->lock);
5284 	}
5285 
5286 	write_unlock_bh(&idev->lock);
5287 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5288 	addrconf_verify_rtnl();
5289 	return 0;
5290 }
5291 
5292 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5293 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5294 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5295 };
5296 
5297 static int inet6_validate_link_af(const struct net_device *dev,
5298 				  const struct nlattr *nla)
5299 {
5300 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5301 
5302 	if (dev && !__in6_dev_get(dev))
5303 		return -EAFNOSUPPORT;
5304 
5305 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5306 				NULL);
5307 }
5308 
5309 static int check_addr_gen_mode(int mode)
5310 {
5311 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5312 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5313 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5314 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5315 		return -EINVAL;
5316 	return 1;
5317 }
5318 
5319 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5320 				int mode)
5321 {
5322 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5323 	    !idev->cnf.stable_secret.initialized &&
5324 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5325 		return -EINVAL;
5326 	return 1;
5327 }
5328 
5329 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5330 {
5331 	int err = -EINVAL;
5332 	struct inet6_dev *idev = __in6_dev_get(dev);
5333 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5334 
5335 	if (!idev)
5336 		return -EAFNOSUPPORT;
5337 
5338 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5339 		BUG();
5340 
5341 	if (tb[IFLA_INET6_TOKEN]) {
5342 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5343 		if (err)
5344 			return err;
5345 	}
5346 
5347 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5348 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5349 
5350 		if (check_addr_gen_mode(mode) < 0 ||
5351 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5352 			return -EINVAL;
5353 
5354 		idev->cnf.addr_gen_mode = mode;
5355 		err = 0;
5356 	}
5357 
5358 	return err;
5359 }
5360 
5361 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5362 			     u32 portid, u32 seq, int event, unsigned int flags)
5363 {
5364 	struct net_device *dev = idev->dev;
5365 	struct ifinfomsg *hdr;
5366 	struct nlmsghdr *nlh;
5367 	void *protoinfo;
5368 
5369 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5370 	if (!nlh)
5371 		return -EMSGSIZE;
5372 
5373 	hdr = nlmsg_data(nlh);
5374 	hdr->ifi_family = AF_INET6;
5375 	hdr->__ifi_pad = 0;
5376 	hdr->ifi_type = dev->type;
5377 	hdr->ifi_index = dev->ifindex;
5378 	hdr->ifi_flags = dev_get_flags(dev);
5379 	hdr->ifi_change = 0;
5380 
5381 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5382 	    (dev->addr_len &&
5383 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5384 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5385 	    (dev->ifindex != dev_get_iflink(dev) &&
5386 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5387 	    nla_put_u8(skb, IFLA_OPERSTATE,
5388 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5389 		goto nla_put_failure;
5390 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5391 	if (!protoinfo)
5392 		goto nla_put_failure;
5393 
5394 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5395 		goto nla_put_failure;
5396 
5397 	nla_nest_end(skb, protoinfo);
5398 	nlmsg_end(skb, nlh);
5399 	return 0;
5400 
5401 nla_put_failure:
5402 	nlmsg_cancel(skb, nlh);
5403 	return -EMSGSIZE;
5404 }
5405 
5406 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5407 {
5408 	struct net *net = sock_net(skb->sk);
5409 	int h, s_h;
5410 	int idx = 0, s_idx;
5411 	struct net_device *dev;
5412 	struct inet6_dev *idev;
5413 	struct hlist_head *head;
5414 
5415 	s_h = cb->args[0];
5416 	s_idx = cb->args[1];
5417 
5418 	rcu_read_lock();
5419 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5420 		idx = 0;
5421 		head = &net->dev_index_head[h];
5422 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5423 			if (idx < s_idx)
5424 				goto cont;
5425 			idev = __in6_dev_get(dev);
5426 			if (!idev)
5427 				goto cont;
5428 			if (inet6_fill_ifinfo(skb, idev,
5429 					      NETLINK_CB(cb->skb).portid,
5430 					      cb->nlh->nlmsg_seq,
5431 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5432 				goto out;
5433 cont:
5434 			idx++;
5435 		}
5436 	}
5437 out:
5438 	rcu_read_unlock();
5439 	cb->args[1] = idx;
5440 	cb->args[0] = h;
5441 
5442 	return skb->len;
5443 }
5444 
5445 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5446 {
5447 	struct sk_buff *skb;
5448 	struct net *net = dev_net(idev->dev);
5449 	int err = -ENOBUFS;
5450 
5451 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5452 	if (!skb)
5453 		goto errout;
5454 
5455 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5456 	if (err < 0) {
5457 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5458 		WARN_ON(err == -EMSGSIZE);
5459 		kfree_skb(skb);
5460 		goto errout;
5461 	}
5462 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5463 	return;
5464 errout:
5465 	if (err < 0)
5466 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5467 }
5468 
5469 static inline size_t inet6_prefix_nlmsg_size(void)
5470 {
5471 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5472 	       + nla_total_size(sizeof(struct in6_addr))
5473 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5474 }
5475 
5476 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5477 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5478 			     int event, unsigned int flags)
5479 {
5480 	struct prefixmsg *pmsg;
5481 	struct nlmsghdr *nlh;
5482 	struct prefix_cacheinfo	ci;
5483 
5484 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5485 	if (!nlh)
5486 		return -EMSGSIZE;
5487 
5488 	pmsg = nlmsg_data(nlh);
5489 	pmsg->prefix_family = AF_INET6;
5490 	pmsg->prefix_pad1 = 0;
5491 	pmsg->prefix_pad2 = 0;
5492 	pmsg->prefix_ifindex = idev->dev->ifindex;
5493 	pmsg->prefix_len = pinfo->prefix_len;
5494 	pmsg->prefix_type = pinfo->type;
5495 	pmsg->prefix_pad3 = 0;
5496 	pmsg->prefix_flags = 0;
5497 	if (pinfo->onlink)
5498 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5499 	if (pinfo->autoconf)
5500 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5501 
5502 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5503 		goto nla_put_failure;
5504 	ci.preferred_time = ntohl(pinfo->prefered);
5505 	ci.valid_time = ntohl(pinfo->valid);
5506 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5507 		goto nla_put_failure;
5508 	nlmsg_end(skb, nlh);
5509 	return 0;
5510 
5511 nla_put_failure:
5512 	nlmsg_cancel(skb, nlh);
5513 	return -EMSGSIZE;
5514 }
5515 
5516 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5517 			 struct prefix_info *pinfo)
5518 {
5519 	struct sk_buff *skb;
5520 	struct net *net = dev_net(idev->dev);
5521 	int err = -ENOBUFS;
5522 
5523 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5524 	if (!skb)
5525 		goto errout;
5526 
5527 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5528 	if (err < 0) {
5529 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5530 		WARN_ON(err == -EMSGSIZE);
5531 		kfree_skb(skb);
5532 		goto errout;
5533 	}
5534 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5535 	return;
5536 errout:
5537 	if (err < 0)
5538 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5539 }
5540 
5541 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5542 {
5543 	struct net *net = dev_net(ifp->idev->dev);
5544 
5545 	if (event)
5546 		ASSERT_RTNL();
5547 
5548 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5549 
5550 	switch (event) {
5551 	case RTM_NEWADDR:
5552 		/*
5553 		 * If the address was optimistic
5554 		 * we inserted the route at the start of
5555 		 * our DAD process, so we don't need
5556 		 * to do it again
5557 		 */
5558 		if (!(ifp->rt->rt6i_node))
5559 			ip6_ins_rt(ifp->rt);
5560 		if (ifp->idev->cnf.forwarding)
5561 			addrconf_join_anycast(ifp);
5562 		if (!ipv6_addr_any(&ifp->peer_addr))
5563 			addrconf_prefix_route(&ifp->peer_addr, 128,
5564 					      ifp->idev->dev, 0, 0);
5565 		break;
5566 	case RTM_DELADDR:
5567 		if (ifp->idev->cnf.forwarding)
5568 			addrconf_leave_anycast(ifp);
5569 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5570 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5571 			struct rt6_info *rt;
5572 
5573 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5574 						       ifp->idev->dev, 0, 0);
5575 			if (rt)
5576 				ip6_del_rt(rt);
5577 		}
5578 		if (ifp->rt) {
5579 			if (dst_hold_safe(&ifp->rt->dst))
5580 				ip6_del_rt(ifp->rt);
5581 		}
5582 		rt_genid_bump_ipv6(net);
5583 		break;
5584 	}
5585 	atomic_inc(&net->ipv6.dev_addr_genid);
5586 }
5587 
5588 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5589 {
5590 	rcu_read_lock_bh();
5591 	if (likely(ifp->idev->dead == 0))
5592 		__ipv6_ifa_notify(event, ifp);
5593 	rcu_read_unlock_bh();
5594 }
5595 
5596 #ifdef CONFIG_SYSCTL
5597 
5598 static
5599 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5600 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5601 {
5602 	int *valp = ctl->data;
5603 	int val = *valp;
5604 	loff_t pos = *ppos;
5605 	struct ctl_table lctl;
5606 	int ret;
5607 
5608 	/*
5609 	 * ctl->data points to idev->cnf.forwarding, we should
5610 	 * not modify it until we get the rtnl lock.
5611 	 */
5612 	lctl = *ctl;
5613 	lctl.data = &val;
5614 
5615 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5616 
5617 	if (write)
5618 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5619 	if (ret)
5620 		*ppos = pos;
5621 	return ret;
5622 }
5623 
5624 static
5625 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5626 			void __user *buffer, size_t *lenp, loff_t *ppos)
5627 {
5628 	struct inet6_dev *idev = ctl->extra1;
5629 	int min_mtu = IPV6_MIN_MTU;
5630 	struct ctl_table lctl;
5631 
5632 	lctl = *ctl;
5633 	lctl.extra1 = &min_mtu;
5634 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5635 
5636 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5637 }
5638 
5639 static void dev_disable_change(struct inet6_dev *idev)
5640 {
5641 	struct netdev_notifier_info info;
5642 
5643 	if (!idev || !idev->dev)
5644 		return;
5645 
5646 	netdev_notifier_info_init(&info, idev->dev);
5647 	if (idev->cnf.disable_ipv6)
5648 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5649 	else
5650 		addrconf_notify(NULL, NETDEV_UP, &info);
5651 }
5652 
5653 static void addrconf_disable_change(struct net *net, __s32 newf)
5654 {
5655 	struct net_device *dev;
5656 	struct inet6_dev *idev;
5657 
5658 	for_each_netdev(net, dev) {
5659 		idev = __in6_dev_get(dev);
5660 		if (idev) {
5661 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5662 			idev->cnf.disable_ipv6 = newf;
5663 			if (changed)
5664 				dev_disable_change(idev);
5665 		}
5666 	}
5667 }
5668 
5669 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5670 {
5671 	struct net *net;
5672 	int old;
5673 
5674 	if (!rtnl_trylock())
5675 		return restart_syscall();
5676 
5677 	net = (struct net *)table->extra2;
5678 	old = *p;
5679 	*p = newf;
5680 
5681 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5682 		rtnl_unlock();
5683 		return 0;
5684 	}
5685 
5686 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5687 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5688 		addrconf_disable_change(net, newf);
5689 	} else if ((!newf) ^ (!old))
5690 		dev_disable_change((struct inet6_dev *)table->extra1);
5691 
5692 	rtnl_unlock();
5693 	return 0;
5694 }
5695 
5696 static
5697 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5698 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5699 {
5700 	int *valp = ctl->data;
5701 	int val = *valp;
5702 	loff_t pos = *ppos;
5703 	struct ctl_table lctl;
5704 	int ret;
5705 
5706 	/*
5707 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5708 	 * not modify it until we get the rtnl lock.
5709 	 */
5710 	lctl = *ctl;
5711 	lctl.data = &val;
5712 
5713 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5714 
5715 	if (write)
5716 		ret = addrconf_disable_ipv6(ctl, valp, val);
5717 	if (ret)
5718 		*ppos = pos;
5719 	return ret;
5720 }
5721 
5722 static
5723 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5724 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5725 {
5726 	int *valp = ctl->data;
5727 	int ret;
5728 	int old, new;
5729 
5730 	old = *valp;
5731 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5732 	new = *valp;
5733 
5734 	if (write && old != new) {
5735 		struct net *net = ctl->extra2;
5736 
5737 		if (!rtnl_trylock())
5738 			return restart_syscall();
5739 
5740 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5741 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5742 						     NETCONFA_PROXY_NEIGH,
5743 						     NETCONFA_IFINDEX_DEFAULT,
5744 						     net->ipv6.devconf_dflt);
5745 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5746 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5747 						     NETCONFA_PROXY_NEIGH,
5748 						     NETCONFA_IFINDEX_ALL,
5749 						     net->ipv6.devconf_all);
5750 		else {
5751 			struct inet6_dev *idev = ctl->extra1;
5752 
5753 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5754 						     NETCONFA_PROXY_NEIGH,
5755 						     idev->dev->ifindex,
5756 						     &idev->cnf);
5757 		}
5758 		rtnl_unlock();
5759 	}
5760 
5761 	return ret;
5762 }
5763 
5764 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5765 					 void __user *buffer, size_t *lenp,
5766 					 loff_t *ppos)
5767 {
5768 	int ret = 0;
5769 	int new_val;
5770 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5771 	struct net *net = (struct net *)ctl->extra2;
5772 
5773 	if (!rtnl_trylock())
5774 		return restart_syscall();
5775 
5776 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5777 
5778 	if (write) {
5779 		new_val = *((int *)ctl->data);
5780 
5781 		if (check_addr_gen_mode(new_val) < 0) {
5782 			ret = -EINVAL;
5783 			goto out;
5784 		}
5785 
5786 		/* request for default */
5787 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5788 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5789 
5790 		/* request for individual net device */
5791 		} else {
5792 			if (!idev)
5793 				goto out;
5794 
5795 			if (check_stable_privacy(idev, net, new_val) < 0) {
5796 				ret = -EINVAL;
5797 				goto out;
5798 			}
5799 
5800 			if (idev->cnf.addr_gen_mode != new_val) {
5801 				idev->cnf.addr_gen_mode = new_val;
5802 				addrconf_dev_config(idev->dev);
5803 			}
5804 		}
5805 	}
5806 
5807 out:
5808 	rtnl_unlock();
5809 
5810 	return ret;
5811 }
5812 
5813 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5814 					 void __user *buffer, size_t *lenp,
5815 					 loff_t *ppos)
5816 {
5817 	int err;
5818 	struct in6_addr addr;
5819 	char str[IPV6_MAX_STRLEN];
5820 	struct ctl_table lctl = *ctl;
5821 	struct net *net = ctl->extra2;
5822 	struct ipv6_stable_secret *secret = ctl->data;
5823 
5824 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5825 		return -EIO;
5826 
5827 	lctl.maxlen = IPV6_MAX_STRLEN;
5828 	lctl.data = str;
5829 
5830 	if (!rtnl_trylock())
5831 		return restart_syscall();
5832 
5833 	if (!write && !secret->initialized) {
5834 		err = -EIO;
5835 		goto out;
5836 	}
5837 
5838 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5839 	if (err >= sizeof(str)) {
5840 		err = -EIO;
5841 		goto out;
5842 	}
5843 
5844 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5845 	if (err || !write)
5846 		goto out;
5847 
5848 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5849 		err = -EIO;
5850 		goto out;
5851 	}
5852 
5853 	secret->initialized = true;
5854 	secret->secret = addr;
5855 
5856 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5857 		struct net_device *dev;
5858 
5859 		for_each_netdev(net, dev) {
5860 			struct inet6_dev *idev = __in6_dev_get(dev);
5861 
5862 			if (idev) {
5863 				idev->cnf.addr_gen_mode =
5864 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5865 			}
5866 		}
5867 	} else {
5868 		struct inet6_dev *idev = ctl->extra1;
5869 
5870 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5871 	}
5872 
5873 out:
5874 	rtnl_unlock();
5875 
5876 	return err;
5877 }
5878 
5879 static
5880 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5881 						int write,
5882 						void __user *buffer,
5883 						size_t *lenp,
5884 						loff_t *ppos)
5885 {
5886 	int *valp = ctl->data;
5887 	int val = *valp;
5888 	loff_t pos = *ppos;
5889 	struct ctl_table lctl;
5890 	int ret;
5891 
5892 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5893 	 * we should not modify it until we get the rtnl lock.
5894 	 */
5895 	lctl = *ctl;
5896 	lctl.data = &val;
5897 
5898 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5899 
5900 	if (write)
5901 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5902 	if (ret)
5903 		*ppos = pos;
5904 	return ret;
5905 }
5906 
5907 static
5908 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5909 {
5910 	if (rt) {
5911 		if (action)
5912 			rt->dst.flags |= DST_NOPOLICY;
5913 		else
5914 			rt->dst.flags &= ~DST_NOPOLICY;
5915 	}
5916 }
5917 
5918 static
5919 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5920 {
5921 	struct inet6_ifaddr *ifa;
5922 
5923 	read_lock_bh(&idev->lock);
5924 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5925 		spin_lock(&ifa->lock);
5926 		if (ifa->rt) {
5927 			struct rt6_info *rt = ifa->rt;
5928 			struct fib6_table *table = rt->rt6i_table;
5929 			int cpu;
5930 
5931 			read_lock(&table->tb6_lock);
5932 			addrconf_set_nopolicy(ifa->rt, val);
5933 			if (rt->rt6i_pcpu) {
5934 				for_each_possible_cpu(cpu) {
5935 					struct rt6_info **rtp;
5936 
5937 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5938 					addrconf_set_nopolicy(*rtp, val);
5939 				}
5940 			}
5941 			read_unlock(&table->tb6_lock);
5942 		}
5943 		spin_unlock(&ifa->lock);
5944 	}
5945 	read_unlock_bh(&idev->lock);
5946 }
5947 
5948 static
5949 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
5950 {
5951 	struct inet6_dev *idev;
5952 	struct net *net;
5953 
5954 	if (!rtnl_trylock())
5955 		return restart_syscall();
5956 
5957 	*valp = val;
5958 
5959 	net = (struct net *)ctl->extra2;
5960 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
5961 		rtnl_unlock();
5962 		return 0;
5963 	}
5964 
5965 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
5966 		struct net_device *dev;
5967 
5968 		for_each_netdev(net, dev) {
5969 			idev = __in6_dev_get(dev);
5970 			if (idev)
5971 				addrconf_disable_policy_idev(idev, val);
5972 		}
5973 	} else {
5974 		idev = (struct inet6_dev *)ctl->extra1;
5975 		addrconf_disable_policy_idev(idev, val);
5976 	}
5977 
5978 	rtnl_unlock();
5979 	return 0;
5980 }
5981 
5982 static
5983 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
5984 				   void __user *buffer, size_t *lenp,
5985 				   loff_t *ppos)
5986 {
5987 	int *valp = ctl->data;
5988 	int val = *valp;
5989 	loff_t pos = *ppos;
5990 	struct ctl_table lctl;
5991 	int ret;
5992 
5993 	lctl = *ctl;
5994 	lctl.data = &val;
5995 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5996 
5997 	if (write && (*valp != val))
5998 		ret = addrconf_disable_policy(ctl, valp, val);
5999 
6000 	if (ret)
6001 		*ppos = pos;
6002 
6003 	return ret;
6004 }
6005 
6006 static int minus_one = -1;
6007 static const int one = 1;
6008 static const int two_five_five = 255;
6009 
6010 static const struct ctl_table addrconf_sysctl[] = {
6011 	{
6012 		.procname	= "forwarding",
6013 		.data		= &ipv6_devconf.forwarding,
6014 		.maxlen		= sizeof(int),
6015 		.mode		= 0644,
6016 		.proc_handler	= addrconf_sysctl_forward,
6017 	},
6018 	{
6019 		.procname	= "hop_limit",
6020 		.data		= &ipv6_devconf.hop_limit,
6021 		.maxlen		= sizeof(int),
6022 		.mode		= 0644,
6023 		.proc_handler	= proc_dointvec_minmax,
6024 		.extra1		= (void *)&one,
6025 		.extra2		= (void *)&two_five_five,
6026 	},
6027 	{
6028 		.procname	= "mtu",
6029 		.data		= &ipv6_devconf.mtu6,
6030 		.maxlen		= sizeof(int),
6031 		.mode		= 0644,
6032 		.proc_handler	= addrconf_sysctl_mtu,
6033 	},
6034 	{
6035 		.procname	= "accept_ra",
6036 		.data		= &ipv6_devconf.accept_ra,
6037 		.maxlen		= sizeof(int),
6038 		.mode		= 0644,
6039 		.proc_handler	= proc_dointvec,
6040 	},
6041 	{
6042 		.procname	= "accept_redirects",
6043 		.data		= &ipv6_devconf.accept_redirects,
6044 		.maxlen		= sizeof(int),
6045 		.mode		= 0644,
6046 		.proc_handler	= proc_dointvec,
6047 	},
6048 	{
6049 		.procname	= "autoconf",
6050 		.data		= &ipv6_devconf.autoconf,
6051 		.maxlen		= sizeof(int),
6052 		.mode		= 0644,
6053 		.proc_handler	= proc_dointvec,
6054 	},
6055 	{
6056 		.procname	= "dad_transmits",
6057 		.data		= &ipv6_devconf.dad_transmits,
6058 		.maxlen		= sizeof(int),
6059 		.mode		= 0644,
6060 		.proc_handler	= proc_dointvec,
6061 	},
6062 	{
6063 		.procname	= "router_solicitations",
6064 		.data		= &ipv6_devconf.rtr_solicits,
6065 		.maxlen		= sizeof(int),
6066 		.mode		= 0644,
6067 		.proc_handler	= proc_dointvec_minmax,
6068 		.extra1		= &minus_one,
6069 	},
6070 	{
6071 		.procname	= "router_solicitation_interval",
6072 		.data		= &ipv6_devconf.rtr_solicit_interval,
6073 		.maxlen		= sizeof(int),
6074 		.mode		= 0644,
6075 		.proc_handler	= proc_dointvec_jiffies,
6076 	},
6077 	{
6078 		.procname	= "router_solicitation_max_interval",
6079 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6080 		.maxlen		= sizeof(int),
6081 		.mode		= 0644,
6082 		.proc_handler	= proc_dointvec_jiffies,
6083 	},
6084 	{
6085 		.procname	= "router_solicitation_delay",
6086 		.data		= &ipv6_devconf.rtr_solicit_delay,
6087 		.maxlen		= sizeof(int),
6088 		.mode		= 0644,
6089 		.proc_handler	= proc_dointvec_jiffies,
6090 	},
6091 	{
6092 		.procname	= "force_mld_version",
6093 		.data		= &ipv6_devconf.force_mld_version,
6094 		.maxlen		= sizeof(int),
6095 		.mode		= 0644,
6096 		.proc_handler	= proc_dointvec,
6097 	},
6098 	{
6099 		.procname	= "mldv1_unsolicited_report_interval",
6100 		.data		=
6101 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6102 		.maxlen		= sizeof(int),
6103 		.mode		= 0644,
6104 		.proc_handler	= proc_dointvec_ms_jiffies,
6105 	},
6106 	{
6107 		.procname	= "mldv2_unsolicited_report_interval",
6108 		.data		=
6109 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6110 		.maxlen		= sizeof(int),
6111 		.mode		= 0644,
6112 		.proc_handler	= proc_dointvec_ms_jiffies,
6113 	},
6114 	{
6115 		.procname	= "use_tempaddr",
6116 		.data		= &ipv6_devconf.use_tempaddr,
6117 		.maxlen		= sizeof(int),
6118 		.mode		= 0644,
6119 		.proc_handler	= proc_dointvec,
6120 	},
6121 	{
6122 		.procname	= "temp_valid_lft",
6123 		.data		= &ipv6_devconf.temp_valid_lft,
6124 		.maxlen		= sizeof(int),
6125 		.mode		= 0644,
6126 		.proc_handler	= proc_dointvec,
6127 	},
6128 	{
6129 		.procname	= "temp_prefered_lft",
6130 		.data		= &ipv6_devconf.temp_prefered_lft,
6131 		.maxlen		= sizeof(int),
6132 		.mode		= 0644,
6133 		.proc_handler	= proc_dointvec,
6134 	},
6135 	{
6136 		.procname	= "regen_max_retry",
6137 		.data		= &ipv6_devconf.regen_max_retry,
6138 		.maxlen		= sizeof(int),
6139 		.mode		= 0644,
6140 		.proc_handler	= proc_dointvec,
6141 	},
6142 	{
6143 		.procname	= "max_desync_factor",
6144 		.data		= &ipv6_devconf.max_desync_factor,
6145 		.maxlen		= sizeof(int),
6146 		.mode		= 0644,
6147 		.proc_handler	= proc_dointvec,
6148 	},
6149 	{
6150 		.procname	= "max_addresses",
6151 		.data		= &ipv6_devconf.max_addresses,
6152 		.maxlen		= sizeof(int),
6153 		.mode		= 0644,
6154 		.proc_handler	= proc_dointvec,
6155 	},
6156 	{
6157 		.procname	= "accept_ra_defrtr",
6158 		.data		= &ipv6_devconf.accept_ra_defrtr,
6159 		.maxlen		= sizeof(int),
6160 		.mode		= 0644,
6161 		.proc_handler	= proc_dointvec,
6162 	},
6163 	{
6164 		.procname	= "accept_ra_min_hop_limit",
6165 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6166 		.maxlen		= sizeof(int),
6167 		.mode		= 0644,
6168 		.proc_handler	= proc_dointvec,
6169 	},
6170 	{
6171 		.procname	= "accept_ra_pinfo",
6172 		.data		= &ipv6_devconf.accept_ra_pinfo,
6173 		.maxlen		= sizeof(int),
6174 		.mode		= 0644,
6175 		.proc_handler	= proc_dointvec,
6176 	},
6177 #ifdef CONFIG_IPV6_ROUTER_PREF
6178 	{
6179 		.procname	= "accept_ra_rtr_pref",
6180 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6181 		.maxlen		= sizeof(int),
6182 		.mode		= 0644,
6183 		.proc_handler	= proc_dointvec,
6184 	},
6185 	{
6186 		.procname	= "router_probe_interval",
6187 		.data		= &ipv6_devconf.rtr_probe_interval,
6188 		.maxlen		= sizeof(int),
6189 		.mode		= 0644,
6190 		.proc_handler	= proc_dointvec_jiffies,
6191 	},
6192 #ifdef CONFIG_IPV6_ROUTE_INFO
6193 	{
6194 		.procname	= "accept_ra_rt_info_min_plen",
6195 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6196 		.maxlen		= sizeof(int),
6197 		.mode		= 0644,
6198 		.proc_handler	= proc_dointvec,
6199 	},
6200 	{
6201 		.procname	= "accept_ra_rt_info_max_plen",
6202 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6203 		.maxlen		= sizeof(int),
6204 		.mode		= 0644,
6205 		.proc_handler	= proc_dointvec,
6206 	},
6207 #endif
6208 #endif
6209 	{
6210 		.procname	= "proxy_ndp",
6211 		.data		= &ipv6_devconf.proxy_ndp,
6212 		.maxlen		= sizeof(int),
6213 		.mode		= 0644,
6214 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6215 	},
6216 	{
6217 		.procname	= "accept_source_route",
6218 		.data		= &ipv6_devconf.accept_source_route,
6219 		.maxlen		= sizeof(int),
6220 		.mode		= 0644,
6221 		.proc_handler	= proc_dointvec,
6222 	},
6223 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6224 	{
6225 		.procname	= "optimistic_dad",
6226 		.data		= &ipv6_devconf.optimistic_dad,
6227 		.maxlen		= sizeof(int),
6228 		.mode		= 0644,
6229 		.proc_handler   = proc_dointvec,
6230 	},
6231 	{
6232 		.procname	= "use_optimistic",
6233 		.data		= &ipv6_devconf.use_optimistic,
6234 		.maxlen		= sizeof(int),
6235 		.mode		= 0644,
6236 		.proc_handler	= proc_dointvec,
6237 	},
6238 #endif
6239 #ifdef CONFIG_IPV6_MROUTE
6240 	{
6241 		.procname	= "mc_forwarding",
6242 		.data		= &ipv6_devconf.mc_forwarding,
6243 		.maxlen		= sizeof(int),
6244 		.mode		= 0444,
6245 		.proc_handler	= proc_dointvec,
6246 	},
6247 #endif
6248 	{
6249 		.procname	= "disable_ipv6",
6250 		.data		= &ipv6_devconf.disable_ipv6,
6251 		.maxlen		= sizeof(int),
6252 		.mode		= 0644,
6253 		.proc_handler	= addrconf_sysctl_disable,
6254 	},
6255 	{
6256 		.procname	= "accept_dad",
6257 		.data		= &ipv6_devconf.accept_dad,
6258 		.maxlen		= sizeof(int),
6259 		.mode		= 0644,
6260 		.proc_handler	= proc_dointvec,
6261 	},
6262 	{
6263 		.procname	= "force_tllao",
6264 		.data		= &ipv6_devconf.force_tllao,
6265 		.maxlen		= sizeof(int),
6266 		.mode		= 0644,
6267 		.proc_handler	= proc_dointvec
6268 	},
6269 	{
6270 		.procname	= "ndisc_notify",
6271 		.data		= &ipv6_devconf.ndisc_notify,
6272 		.maxlen		= sizeof(int),
6273 		.mode		= 0644,
6274 		.proc_handler	= proc_dointvec
6275 	},
6276 	{
6277 		.procname	= "suppress_frag_ndisc",
6278 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6279 		.maxlen		= sizeof(int),
6280 		.mode		= 0644,
6281 		.proc_handler	= proc_dointvec
6282 	},
6283 	{
6284 		.procname	= "accept_ra_from_local",
6285 		.data		= &ipv6_devconf.accept_ra_from_local,
6286 		.maxlen		= sizeof(int),
6287 		.mode		= 0644,
6288 		.proc_handler	= proc_dointvec,
6289 	},
6290 	{
6291 		.procname	= "accept_ra_mtu",
6292 		.data		= &ipv6_devconf.accept_ra_mtu,
6293 		.maxlen		= sizeof(int),
6294 		.mode		= 0644,
6295 		.proc_handler	= proc_dointvec,
6296 	},
6297 	{
6298 		.procname	= "stable_secret",
6299 		.data		= &ipv6_devconf.stable_secret,
6300 		.maxlen		= IPV6_MAX_STRLEN,
6301 		.mode		= 0600,
6302 		.proc_handler	= addrconf_sysctl_stable_secret,
6303 	},
6304 	{
6305 		.procname	= "use_oif_addrs_only",
6306 		.data		= &ipv6_devconf.use_oif_addrs_only,
6307 		.maxlen		= sizeof(int),
6308 		.mode		= 0644,
6309 		.proc_handler	= proc_dointvec,
6310 	},
6311 	{
6312 		.procname	= "ignore_routes_with_linkdown",
6313 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6314 		.maxlen		= sizeof(int),
6315 		.mode		= 0644,
6316 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6317 	},
6318 	{
6319 		.procname	= "drop_unicast_in_l2_multicast",
6320 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6321 		.maxlen		= sizeof(int),
6322 		.mode		= 0644,
6323 		.proc_handler	= proc_dointvec,
6324 	},
6325 	{
6326 		.procname	= "drop_unsolicited_na",
6327 		.data		= &ipv6_devconf.drop_unsolicited_na,
6328 		.maxlen		= sizeof(int),
6329 		.mode		= 0644,
6330 		.proc_handler	= proc_dointvec,
6331 	},
6332 	{
6333 		.procname	= "keep_addr_on_down",
6334 		.data		= &ipv6_devconf.keep_addr_on_down,
6335 		.maxlen		= sizeof(int),
6336 		.mode		= 0644,
6337 		.proc_handler	= proc_dointvec,
6338 
6339 	},
6340 	{
6341 		.procname	= "seg6_enabled",
6342 		.data		= &ipv6_devconf.seg6_enabled,
6343 		.maxlen		= sizeof(int),
6344 		.mode		= 0644,
6345 		.proc_handler	= proc_dointvec,
6346 	},
6347 #ifdef CONFIG_IPV6_SEG6_HMAC
6348 	{
6349 		.procname	= "seg6_require_hmac",
6350 		.data		= &ipv6_devconf.seg6_require_hmac,
6351 		.maxlen		= sizeof(int),
6352 		.mode		= 0644,
6353 		.proc_handler	= proc_dointvec,
6354 	},
6355 #endif
6356 	{
6357 		.procname       = "enhanced_dad",
6358 		.data           = &ipv6_devconf.enhanced_dad,
6359 		.maxlen         = sizeof(int),
6360 		.mode           = 0644,
6361 		.proc_handler   = proc_dointvec,
6362 	},
6363 	{
6364 		.procname		= "addr_gen_mode",
6365 		.data			= &ipv6_devconf.addr_gen_mode,
6366 		.maxlen			= sizeof(int),
6367 		.mode			= 0644,
6368 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6369 	},
6370 	{
6371 		.procname       = "disable_policy",
6372 		.data           = &ipv6_devconf.disable_policy,
6373 		.maxlen         = sizeof(int),
6374 		.mode           = 0644,
6375 		.proc_handler   = addrconf_sysctl_disable_policy,
6376 	},
6377 	{
6378 		/* sentinel */
6379 	}
6380 };
6381 
6382 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6383 		struct inet6_dev *idev, struct ipv6_devconf *p)
6384 {
6385 	int i, ifindex;
6386 	struct ctl_table *table;
6387 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6388 
6389 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6390 	if (!table)
6391 		goto out;
6392 
6393 	for (i = 0; table[i].data; i++) {
6394 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6395 		/* If one of these is already set, then it is not safe to
6396 		 * overwrite either of them: this makes proc_dointvec_minmax
6397 		 * usable.
6398 		 */
6399 		if (!table[i].extra1 && !table[i].extra2) {
6400 			table[i].extra1 = idev; /* embedded; no ref */
6401 			table[i].extra2 = net;
6402 		}
6403 	}
6404 
6405 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6406 
6407 	p->sysctl_header = register_net_sysctl(net, path, table);
6408 	if (!p->sysctl_header)
6409 		goto free;
6410 
6411 	if (!strcmp(dev_name, "all"))
6412 		ifindex = NETCONFA_IFINDEX_ALL;
6413 	else if (!strcmp(dev_name, "default"))
6414 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6415 	else
6416 		ifindex = idev->dev->ifindex;
6417 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6418 				     ifindex, p);
6419 	return 0;
6420 
6421 free:
6422 	kfree(table);
6423 out:
6424 	return -ENOBUFS;
6425 }
6426 
6427 static void __addrconf_sysctl_unregister(struct net *net,
6428 					 struct ipv6_devconf *p, int ifindex)
6429 {
6430 	struct ctl_table *table;
6431 
6432 	if (!p->sysctl_header)
6433 		return;
6434 
6435 	table = p->sysctl_header->ctl_table_arg;
6436 	unregister_net_sysctl_table(p->sysctl_header);
6437 	p->sysctl_header = NULL;
6438 	kfree(table);
6439 
6440 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6441 }
6442 
6443 static int addrconf_sysctl_register(struct inet6_dev *idev)
6444 {
6445 	int err;
6446 
6447 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6448 		return -EINVAL;
6449 
6450 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6451 				    &ndisc_ifinfo_sysctl_change);
6452 	if (err)
6453 		return err;
6454 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6455 					 idev, &idev->cnf);
6456 	if (err)
6457 		neigh_sysctl_unregister(idev->nd_parms);
6458 
6459 	return err;
6460 }
6461 
6462 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6463 {
6464 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6465 				     idev->dev->ifindex);
6466 	neigh_sysctl_unregister(idev->nd_parms);
6467 }
6468 
6469 
6470 #endif
6471 
6472 static int __net_init addrconf_init_net(struct net *net)
6473 {
6474 	int err = -ENOMEM;
6475 	struct ipv6_devconf *all, *dflt;
6476 
6477 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6478 	if (!all)
6479 		goto err_alloc_all;
6480 
6481 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6482 	if (!dflt)
6483 		goto err_alloc_dflt;
6484 
6485 	/* these will be inherited by all namespaces */
6486 	dflt->autoconf = ipv6_defaults.autoconf;
6487 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6488 
6489 	dflt->stable_secret.initialized = false;
6490 	all->stable_secret.initialized = false;
6491 
6492 	net->ipv6.devconf_all = all;
6493 	net->ipv6.devconf_dflt = dflt;
6494 
6495 #ifdef CONFIG_SYSCTL
6496 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6497 	if (err < 0)
6498 		goto err_reg_all;
6499 
6500 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6501 	if (err < 0)
6502 		goto err_reg_dflt;
6503 #endif
6504 	return 0;
6505 
6506 #ifdef CONFIG_SYSCTL
6507 err_reg_dflt:
6508 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6509 err_reg_all:
6510 	kfree(dflt);
6511 #endif
6512 err_alloc_dflt:
6513 	kfree(all);
6514 err_alloc_all:
6515 	return err;
6516 }
6517 
6518 static void __net_exit addrconf_exit_net(struct net *net)
6519 {
6520 #ifdef CONFIG_SYSCTL
6521 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6522 				     NETCONFA_IFINDEX_DEFAULT);
6523 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6524 				     NETCONFA_IFINDEX_ALL);
6525 #endif
6526 	kfree(net->ipv6.devconf_dflt);
6527 	kfree(net->ipv6.devconf_all);
6528 }
6529 
6530 static struct pernet_operations addrconf_ops = {
6531 	.init = addrconf_init_net,
6532 	.exit = addrconf_exit_net,
6533 };
6534 
6535 static struct rtnl_af_ops inet6_ops __read_mostly = {
6536 	.family		  = AF_INET6,
6537 	.fill_link_af	  = inet6_fill_link_af,
6538 	.get_link_af_size = inet6_get_link_af_size,
6539 	.validate_link_af = inet6_validate_link_af,
6540 	.set_link_af	  = inet6_set_link_af,
6541 };
6542 
6543 /*
6544  *	Init / cleanup code
6545  */
6546 
6547 int __init addrconf_init(void)
6548 {
6549 	struct inet6_dev *idev;
6550 	int i, err;
6551 
6552 	err = ipv6_addr_label_init();
6553 	if (err < 0) {
6554 		pr_crit("%s: cannot initialize default policy table: %d\n",
6555 			__func__, err);
6556 		goto out;
6557 	}
6558 
6559 	err = register_pernet_subsys(&addrconf_ops);
6560 	if (err < 0)
6561 		goto out_addrlabel;
6562 
6563 	addrconf_wq = create_workqueue("ipv6_addrconf");
6564 	if (!addrconf_wq) {
6565 		err = -ENOMEM;
6566 		goto out_nowq;
6567 	}
6568 
6569 	/* The addrconf netdev notifier requires that loopback_dev
6570 	 * has it's ipv6 private information allocated and setup
6571 	 * before it can bring up and give link-local addresses
6572 	 * to other devices which are up.
6573 	 *
6574 	 * Unfortunately, loopback_dev is not necessarily the first
6575 	 * entry in the global dev_base list of net devices.  In fact,
6576 	 * it is likely to be the very last entry on that list.
6577 	 * So this causes the notifier registry below to try and
6578 	 * give link-local addresses to all devices besides loopback_dev
6579 	 * first, then loopback_dev, which cases all the non-loopback_dev
6580 	 * devices to fail to get a link-local address.
6581 	 *
6582 	 * So, as a temporary fix, allocate the ipv6 structure for
6583 	 * loopback_dev first by hand.
6584 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6585 	 * device and it being up should be removed.
6586 	 */
6587 	rtnl_lock();
6588 	idev = ipv6_add_dev(init_net.loopback_dev);
6589 	rtnl_unlock();
6590 	if (IS_ERR(idev)) {
6591 		err = PTR_ERR(idev);
6592 		goto errlo;
6593 	}
6594 
6595 	ip6_route_init_special_entries();
6596 
6597 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6598 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6599 
6600 	register_netdevice_notifier(&ipv6_dev_notf);
6601 
6602 	addrconf_verify();
6603 
6604 	rtnl_af_register(&inet6_ops);
6605 
6606 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
6607 			      NULL);
6608 	if (err < 0)
6609 		goto errout;
6610 
6611 	/* Only the first call to __rtnl_register can fail */
6612 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
6613 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
6614 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
6615 			inet6_dump_ifaddr, NULL);
6616 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
6617 			inet6_dump_ifmcaddr, NULL);
6618 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
6619 			inet6_dump_ifacaddr, NULL);
6620 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
6621 			inet6_netconf_dump_devconf, NULL);
6622 
6623 	ipv6_addr_label_rtnl_register();
6624 
6625 	return 0;
6626 errout:
6627 	rtnl_af_unregister(&inet6_ops);
6628 	unregister_netdevice_notifier(&ipv6_dev_notf);
6629 errlo:
6630 	destroy_workqueue(addrconf_wq);
6631 out_nowq:
6632 	unregister_pernet_subsys(&addrconf_ops);
6633 out_addrlabel:
6634 	ipv6_addr_label_cleanup();
6635 out:
6636 	return err;
6637 }
6638 
6639 void addrconf_cleanup(void)
6640 {
6641 	struct net_device *dev;
6642 	int i;
6643 
6644 	unregister_netdevice_notifier(&ipv6_dev_notf);
6645 	unregister_pernet_subsys(&addrconf_ops);
6646 	ipv6_addr_label_cleanup();
6647 
6648 	rtnl_lock();
6649 
6650 	__rtnl_af_unregister(&inet6_ops);
6651 
6652 	/* clean dev list */
6653 	for_each_netdev(&init_net, dev) {
6654 		if (__in6_dev_get(dev) == NULL)
6655 			continue;
6656 		addrconf_ifdown(dev, 1);
6657 	}
6658 	addrconf_ifdown(init_net.loopback_dev, 2);
6659 
6660 	/*
6661 	 *	Check hash table.
6662 	 */
6663 	spin_lock_bh(&addrconf_hash_lock);
6664 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6665 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6666 	spin_unlock_bh(&addrconf_hash_lock);
6667 	cancel_delayed_work(&addr_chk_work);
6668 	rtnl_unlock();
6669 
6670 	destroy_workqueue(addrconf_wq);
6671 }
6672