xref: /openbmc/linux/net/ipv6/addrconf.c (revision d2ba09c1)
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 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181 				   bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188 				struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191 	.forwarding		= 0,
192 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
193 	.mtu6			= IPV6_MIN_MTU,
194 	.accept_ra		= 1,
195 	.accept_redirects	= 1,
196 	.autoconf		= 1,
197 	.force_mld_version	= 0,
198 	.mldv1_unsolicited_report_interval = 10 * HZ,
199 	.mldv2_unsolicited_report_interval = HZ,
200 	.dad_transmits		= 1,
201 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
202 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
203 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
205 	.use_tempaddr		= 0,
206 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
207 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
208 	.regen_max_retry	= REGEN_MAX_RETRY,
209 	.max_desync_factor	= MAX_DESYNC_FACTOR,
210 	.max_addresses		= IPV6_MAX_ADDRESSES,
211 	.accept_ra_defrtr	= 1,
212 	.accept_ra_from_local	= 0,
213 	.accept_ra_min_hop_limit= 1,
214 	.accept_ra_pinfo	= 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216 	.accept_ra_rtr_pref	= 1,
217 	.rtr_probe_interval	= 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219 	.accept_ra_rt_info_min_plen = 0,
220 	.accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223 	.proxy_ndp		= 0,
224 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
225 	.disable_ipv6		= 0,
226 	.accept_dad		= 0,
227 	.suppress_frag_ndisc	= 1,
228 	.accept_ra_mtu		= 1,
229 	.stable_secret		= {
230 		.initialized = false,
231 	},
232 	.use_oif_addrs_only	= 0,
233 	.ignore_routes_with_linkdown = 0,
234 	.keep_addr_on_down	= 0,
235 	.seg6_enabled		= 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237 	.seg6_require_hmac	= 0,
238 #endif
239 	.enhanced_dad           = 1,
240 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
241 	.disable_policy		= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.accept_ra_from_local	= 0,
267 	.accept_ra_min_hop_limit= 1,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 	else
389 		ndev->cnf.addr_gen_mode = ipv6_devconf_dflt.addr_gen_mode;
390 
391 	ndev->cnf.mtu6 = dev->mtu;
392 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
393 	if (!ndev->nd_parms) {
394 		kfree(ndev);
395 		return ERR_PTR(err);
396 	}
397 	if (ndev->cnf.forwarding)
398 		dev_disable_lro(dev);
399 	/* We refer to the device */
400 	dev_hold(dev);
401 
402 	if (snmp6_alloc_dev(ndev) < 0) {
403 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
404 			   __func__);
405 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
406 		dev_put(dev);
407 		kfree(ndev);
408 		return ERR_PTR(err);
409 	}
410 
411 	if (snmp6_register_dev(ndev) < 0) {
412 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
413 			   __func__, dev->name);
414 		goto err_release;
415 	}
416 
417 	/* One reference from device. */
418 	refcount_set(&ndev->refcnt, 1);
419 
420 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
421 		ndev->cnf.accept_dad = -1;
422 
423 #if IS_ENABLED(CONFIG_IPV6_SIT)
424 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
425 		pr_info("%s: Disabled Multicast RS\n", dev->name);
426 		ndev->cnf.rtr_solicits = 0;
427 	}
428 #endif
429 
430 	INIT_LIST_HEAD(&ndev->tempaddr_list);
431 	ndev->desync_factor = U32_MAX;
432 	if ((dev->flags&IFF_LOOPBACK) ||
433 	    dev->type == ARPHRD_TUNNEL ||
434 	    dev->type == ARPHRD_TUNNEL6 ||
435 	    dev->type == ARPHRD_SIT ||
436 	    dev->type == ARPHRD_NONE) {
437 		ndev->cnf.use_tempaddr = -1;
438 	} else
439 		ipv6_regen_rndid(ndev);
440 
441 	ndev->token = in6addr_any;
442 
443 	if (netif_running(dev) && addrconf_link_ready(dev))
444 		ndev->if_flags |= IF_READY;
445 
446 	ipv6_mc_init_dev(ndev);
447 	ndev->tstamp = jiffies;
448 	err = addrconf_sysctl_register(ndev);
449 	if (err) {
450 		ipv6_mc_destroy_dev(ndev);
451 		snmp6_unregister_dev(ndev);
452 		goto err_release;
453 	}
454 	/* protected by rtnl_lock */
455 	rcu_assign_pointer(dev->ip6_ptr, ndev);
456 
457 	/* Join interface-local all-node multicast group */
458 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
459 
460 	/* Join all-node multicast group */
461 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
462 
463 	/* Join all-router multicast group if forwarding is set */
464 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
465 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
466 
467 	return ndev;
468 
469 err_release:
470 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
471 	ndev->dead = 1;
472 	in6_dev_finish_destroy(ndev);
473 	return ERR_PTR(err);
474 }
475 
476 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
477 {
478 	struct inet6_dev *idev;
479 
480 	ASSERT_RTNL();
481 
482 	idev = __in6_dev_get(dev);
483 	if (!idev) {
484 		idev = ipv6_add_dev(dev);
485 		if (IS_ERR(idev))
486 			return NULL;
487 	}
488 
489 	if (dev->flags&IFF_UP)
490 		ipv6_mc_up(idev);
491 	return idev;
492 }
493 
494 static int inet6_netconf_msgsize_devconf(int type)
495 {
496 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
497 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
498 	bool all = false;
499 
500 	if (type == NETCONFA_ALL)
501 		all = true;
502 
503 	if (all || type == NETCONFA_FORWARDING)
504 		size += nla_total_size(4);
505 #ifdef CONFIG_IPV6_MROUTE
506 	if (all || type == NETCONFA_MC_FORWARDING)
507 		size += nla_total_size(4);
508 #endif
509 	if (all || type == NETCONFA_PROXY_NEIGH)
510 		size += nla_total_size(4);
511 
512 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
513 		size += nla_total_size(4);
514 
515 	return size;
516 }
517 
518 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
519 				      struct ipv6_devconf *devconf, u32 portid,
520 				      u32 seq, int event, unsigned int flags,
521 				      int type)
522 {
523 	struct nlmsghdr  *nlh;
524 	struct netconfmsg *ncm;
525 	bool all = false;
526 
527 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
528 			flags);
529 	if (!nlh)
530 		return -EMSGSIZE;
531 
532 	if (type == NETCONFA_ALL)
533 		all = true;
534 
535 	ncm = nlmsg_data(nlh);
536 	ncm->ncm_family = AF_INET6;
537 
538 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
539 		goto nla_put_failure;
540 
541 	if (!devconf)
542 		goto out;
543 
544 	if ((all || type == NETCONFA_FORWARDING) &&
545 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
546 		goto nla_put_failure;
547 #ifdef CONFIG_IPV6_MROUTE
548 	if ((all || type == NETCONFA_MC_FORWARDING) &&
549 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
550 			devconf->mc_forwarding) < 0)
551 		goto nla_put_failure;
552 #endif
553 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
554 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
555 		goto nla_put_failure;
556 
557 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
558 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
559 			devconf->ignore_routes_with_linkdown) < 0)
560 		goto nla_put_failure;
561 
562 out:
563 	nlmsg_end(skb, nlh);
564 	return 0;
565 
566 nla_put_failure:
567 	nlmsg_cancel(skb, nlh);
568 	return -EMSGSIZE;
569 }
570 
571 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
572 				  int ifindex, struct ipv6_devconf *devconf)
573 {
574 	struct sk_buff *skb;
575 	int err = -ENOBUFS;
576 
577 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
578 	if (!skb)
579 		goto errout;
580 
581 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
582 					 event, 0, type);
583 	if (err < 0) {
584 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
585 		WARN_ON(err == -EMSGSIZE);
586 		kfree_skb(skb);
587 		goto errout;
588 	}
589 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
590 	return;
591 errout:
592 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
593 }
594 
595 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
596 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
597 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
598 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
599 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
600 };
601 
602 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
603 				     struct nlmsghdr *nlh,
604 				     struct netlink_ext_ack *extack)
605 {
606 	struct net *net = sock_net(in_skb->sk);
607 	struct nlattr *tb[NETCONFA_MAX+1];
608 	struct inet6_dev *in6_dev = NULL;
609 	struct net_device *dev = NULL;
610 	struct netconfmsg *ncm;
611 	struct sk_buff *skb;
612 	struct ipv6_devconf *devconf;
613 	int ifindex;
614 	int err;
615 
616 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
617 			  devconf_ipv6_policy, extack);
618 	if (err < 0)
619 		return err;
620 
621 	if (!tb[NETCONFA_IFINDEX])
622 		return -EINVAL;
623 
624 	err = -EINVAL;
625 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
626 	switch (ifindex) {
627 	case NETCONFA_IFINDEX_ALL:
628 		devconf = net->ipv6.devconf_all;
629 		break;
630 	case NETCONFA_IFINDEX_DEFAULT:
631 		devconf = net->ipv6.devconf_dflt;
632 		break;
633 	default:
634 		dev = dev_get_by_index(net, ifindex);
635 		if (!dev)
636 			return -EINVAL;
637 		in6_dev = in6_dev_get(dev);
638 		if (!in6_dev)
639 			goto errout;
640 		devconf = &in6_dev->cnf;
641 		break;
642 	}
643 
644 	err = -ENOBUFS;
645 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
646 	if (!skb)
647 		goto errout;
648 
649 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
650 					 NETLINK_CB(in_skb).portid,
651 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
652 					 NETCONFA_ALL);
653 	if (err < 0) {
654 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
655 		WARN_ON(err == -EMSGSIZE);
656 		kfree_skb(skb);
657 		goto errout;
658 	}
659 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
660 errout:
661 	if (in6_dev)
662 		in6_dev_put(in6_dev);
663 	if (dev)
664 		dev_put(dev);
665 	return err;
666 }
667 
668 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
669 				      struct netlink_callback *cb)
670 {
671 	struct net *net = sock_net(skb->sk);
672 	int h, s_h;
673 	int idx, s_idx;
674 	struct net_device *dev;
675 	struct inet6_dev *idev;
676 	struct hlist_head *head;
677 
678 	s_h = cb->args[0];
679 	s_idx = idx = cb->args[1];
680 
681 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
682 		idx = 0;
683 		head = &net->dev_index_head[h];
684 		rcu_read_lock();
685 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
686 			  net->dev_base_seq;
687 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
688 			if (idx < s_idx)
689 				goto cont;
690 			idev = __in6_dev_get(dev);
691 			if (!idev)
692 				goto cont;
693 
694 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
695 						       &idev->cnf,
696 						       NETLINK_CB(cb->skb).portid,
697 						       cb->nlh->nlmsg_seq,
698 						       RTM_NEWNETCONF,
699 						       NLM_F_MULTI,
700 						       NETCONFA_ALL) < 0) {
701 				rcu_read_unlock();
702 				goto done;
703 			}
704 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
705 cont:
706 			idx++;
707 		}
708 		rcu_read_unlock();
709 	}
710 	if (h == NETDEV_HASHENTRIES) {
711 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
712 					       net->ipv6.devconf_all,
713 					       NETLINK_CB(cb->skb).portid,
714 					       cb->nlh->nlmsg_seq,
715 					       RTM_NEWNETCONF, NLM_F_MULTI,
716 					       NETCONFA_ALL) < 0)
717 			goto done;
718 		else
719 			h++;
720 	}
721 	if (h == NETDEV_HASHENTRIES + 1) {
722 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
723 					       net->ipv6.devconf_dflt,
724 					       NETLINK_CB(cb->skb).portid,
725 					       cb->nlh->nlmsg_seq,
726 					       RTM_NEWNETCONF, NLM_F_MULTI,
727 					       NETCONFA_ALL) < 0)
728 			goto done;
729 		else
730 			h++;
731 	}
732 done:
733 	cb->args[0] = h;
734 	cb->args[1] = idx;
735 
736 	return skb->len;
737 }
738 
739 #ifdef CONFIG_SYSCTL
740 static void dev_forward_change(struct inet6_dev *idev)
741 {
742 	struct net_device *dev;
743 	struct inet6_ifaddr *ifa;
744 
745 	if (!idev)
746 		return;
747 	dev = idev->dev;
748 	if (idev->cnf.forwarding)
749 		dev_disable_lro(dev);
750 	if (dev->flags & IFF_MULTICAST) {
751 		if (idev->cnf.forwarding) {
752 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
753 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
754 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
755 		} else {
756 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
757 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
758 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
759 		}
760 	}
761 
762 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
763 		if (ifa->flags&IFA_F_TENTATIVE)
764 			continue;
765 		if (idev->cnf.forwarding)
766 			addrconf_join_anycast(ifa);
767 		else
768 			addrconf_leave_anycast(ifa);
769 	}
770 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
771 				     NETCONFA_FORWARDING,
772 				     dev->ifindex, &idev->cnf);
773 }
774 
775 
776 static void addrconf_forward_change(struct net *net, __s32 newf)
777 {
778 	struct net_device *dev;
779 	struct inet6_dev *idev;
780 
781 	for_each_netdev(net, dev) {
782 		idev = __in6_dev_get(dev);
783 		if (idev) {
784 			int changed = (!idev->cnf.forwarding) ^ (!newf);
785 			idev->cnf.forwarding = newf;
786 			if (changed)
787 				dev_forward_change(idev);
788 		}
789 	}
790 }
791 
792 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
793 {
794 	struct net *net;
795 	int old;
796 
797 	if (!rtnl_trylock())
798 		return restart_syscall();
799 
800 	net = (struct net *)table->extra2;
801 	old = *p;
802 	*p = newf;
803 
804 	if (p == &net->ipv6.devconf_dflt->forwarding) {
805 		if ((!newf) ^ (!old))
806 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
807 						     NETCONFA_FORWARDING,
808 						     NETCONFA_IFINDEX_DEFAULT,
809 						     net->ipv6.devconf_dflt);
810 		rtnl_unlock();
811 		return 0;
812 	}
813 
814 	if (p == &net->ipv6.devconf_all->forwarding) {
815 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
816 
817 		net->ipv6.devconf_dflt->forwarding = newf;
818 		if ((!newf) ^ (!old_dflt))
819 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
820 						     NETCONFA_FORWARDING,
821 						     NETCONFA_IFINDEX_DEFAULT,
822 						     net->ipv6.devconf_dflt);
823 
824 		addrconf_forward_change(net, newf);
825 		if ((!newf) ^ (!old))
826 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
827 						     NETCONFA_FORWARDING,
828 						     NETCONFA_IFINDEX_ALL,
829 						     net->ipv6.devconf_all);
830 	} else if ((!newf) ^ (!old))
831 		dev_forward_change((struct inet6_dev *)table->extra1);
832 	rtnl_unlock();
833 
834 	if (newf)
835 		rt6_purge_dflt_routers(net);
836 	return 1;
837 }
838 
839 static void addrconf_linkdown_change(struct net *net, __s32 newf)
840 {
841 	struct net_device *dev;
842 	struct inet6_dev *idev;
843 
844 	for_each_netdev(net, dev) {
845 		idev = __in6_dev_get(dev);
846 		if (idev) {
847 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
848 
849 			idev->cnf.ignore_routes_with_linkdown = newf;
850 			if (changed)
851 				inet6_netconf_notify_devconf(dev_net(dev),
852 							     RTM_NEWNETCONF,
853 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
854 							     dev->ifindex,
855 							     &idev->cnf);
856 		}
857 	}
858 }
859 
860 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
861 {
862 	struct net *net;
863 	int old;
864 
865 	if (!rtnl_trylock())
866 		return restart_syscall();
867 
868 	net = (struct net *)table->extra2;
869 	old = *p;
870 	*p = newf;
871 
872 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
873 		if ((!newf) ^ (!old))
874 			inet6_netconf_notify_devconf(net,
875 						     RTM_NEWNETCONF,
876 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
877 						     NETCONFA_IFINDEX_DEFAULT,
878 						     net->ipv6.devconf_dflt);
879 		rtnl_unlock();
880 		return 0;
881 	}
882 
883 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
884 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
885 		addrconf_linkdown_change(net, newf);
886 		if ((!newf) ^ (!old))
887 			inet6_netconf_notify_devconf(net,
888 						     RTM_NEWNETCONF,
889 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
890 						     NETCONFA_IFINDEX_ALL,
891 						     net->ipv6.devconf_all);
892 	}
893 	rtnl_unlock();
894 
895 	return 1;
896 }
897 
898 #endif
899 
900 /* Nobody refers to this ifaddr, destroy it */
901 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
902 {
903 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
904 
905 #ifdef NET_REFCNT_DEBUG
906 	pr_debug("%s\n", __func__);
907 #endif
908 
909 	in6_dev_put(ifp->idev);
910 
911 	if (cancel_delayed_work(&ifp->dad_work))
912 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
913 			  ifp);
914 
915 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
916 		pr_warn("Freeing alive inet6 address %p\n", ifp);
917 		return;
918 	}
919 
920 	kfree_rcu(ifp, rcu);
921 }
922 
923 static void
924 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
925 {
926 	struct list_head *p;
927 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
928 
929 	/*
930 	 * Each device address list is sorted in order of scope -
931 	 * global before linklocal.
932 	 */
933 	list_for_each(p, &idev->addr_list) {
934 		struct inet6_ifaddr *ifa
935 			= list_entry(p, struct inet6_ifaddr, if_list);
936 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
937 			break;
938 	}
939 
940 	list_add_tail_rcu(&ifp->if_list, p);
941 }
942 
943 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
944 {
945 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
946 
947 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
948 }
949 
950 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
951 			       struct net_device *dev, unsigned int hash)
952 {
953 	struct inet6_ifaddr *ifp;
954 
955 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
956 		if (!net_eq(dev_net(ifp->idev->dev), net))
957 			continue;
958 		if (ipv6_addr_equal(&ifp->addr, addr)) {
959 			if (!dev || ifp->idev->dev == dev)
960 				return true;
961 		}
962 	}
963 	return false;
964 }
965 
966 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
967 {
968 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
969 	int err = 0;
970 
971 	spin_lock(&addrconf_hash_lock);
972 
973 	/* Ignore adding duplicate addresses on an interface */
974 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
975 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
976 		err = -EEXIST;
977 	} else {
978 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
979 	}
980 
981 	spin_unlock(&addrconf_hash_lock);
982 
983 	return err;
984 }
985 
986 /* On success it returns ifp with increased reference count */
987 
988 static struct inet6_ifaddr *
989 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
990 	      const struct in6_addr *peer_addr, int pfxlen,
991 	      int scope, u32 flags, u32 valid_lft, u32 prefered_lft,
992 	      bool can_block, struct netlink_ext_ack *extack)
993 {
994 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
995 	struct net *net = dev_net(idev->dev);
996 	struct inet6_ifaddr *ifa = NULL;
997 	struct fib6_info *f6i = NULL;
998 	int err = 0;
999 	int addr_type = ipv6_addr_type(addr);
1000 
1001 	if (addr_type == IPV6_ADDR_ANY ||
1002 	    addr_type & IPV6_ADDR_MULTICAST ||
1003 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1004 	     addr_type & IPV6_ADDR_LOOPBACK))
1005 		return ERR_PTR(-EADDRNOTAVAIL);
1006 
1007 	if (idev->dead) {
1008 		err = -ENODEV;			/*XXX*/
1009 		goto out;
1010 	}
1011 
1012 	if (idev->cnf.disable_ipv6) {
1013 		err = -EACCES;
1014 		goto out;
1015 	}
1016 
1017 	/* validator notifier needs to be blocking;
1018 	 * do not call in atomic context
1019 	 */
1020 	if (can_block) {
1021 		struct in6_validator_info i6vi = {
1022 			.i6vi_addr = *addr,
1023 			.i6vi_dev = idev,
1024 			.extack = extack,
1025 		};
1026 
1027 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1028 		err = notifier_to_errno(err);
1029 		if (err < 0)
1030 			goto out;
1031 	}
1032 
1033 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1034 	if (!ifa) {
1035 		err = -ENOBUFS;
1036 		goto out;
1037 	}
1038 
1039 	f6i = addrconf_f6i_alloc(net, idev, addr, false, gfp_flags);
1040 	if (IS_ERR(f6i)) {
1041 		err = PTR_ERR(f6i);
1042 		f6i = NULL;
1043 		goto out;
1044 	}
1045 
1046 	if (net->ipv6.devconf_all->disable_policy ||
1047 	    idev->cnf.disable_policy)
1048 		f6i->dst_nopolicy = true;
1049 
1050 	neigh_parms_data_state_setall(idev->nd_parms);
1051 
1052 	ifa->addr = *addr;
1053 	if (peer_addr)
1054 		ifa->peer_addr = *peer_addr;
1055 
1056 	spin_lock_init(&ifa->lock);
1057 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1058 	INIT_HLIST_NODE(&ifa->addr_lst);
1059 	ifa->scope = scope;
1060 	ifa->prefix_len = pfxlen;
1061 	ifa->flags = flags;
1062 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1063 	if (!(flags & IFA_F_NODAD))
1064 		ifa->flags |= IFA_F_TENTATIVE;
1065 	ifa->valid_lft = valid_lft;
1066 	ifa->prefered_lft = prefered_lft;
1067 	ifa->cstamp = ifa->tstamp = jiffies;
1068 	ifa->tokenized = false;
1069 
1070 	ifa->rt = f6i;
1071 
1072 	ifa->idev = idev;
1073 	in6_dev_hold(idev);
1074 
1075 	/* For caller */
1076 	refcount_set(&ifa->refcnt, 1);
1077 
1078 	rcu_read_lock_bh();
1079 
1080 	err = ipv6_add_addr_hash(idev->dev, ifa);
1081 	if (err < 0) {
1082 		rcu_read_unlock_bh();
1083 		goto out;
1084 	}
1085 
1086 	write_lock(&idev->lock);
1087 
1088 	/* Add to inet6_dev unicast addr list. */
1089 	ipv6_link_dev_addr(idev, ifa);
1090 
1091 	if (ifa->flags&IFA_F_TEMPORARY) {
1092 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1093 		in6_ifa_hold(ifa);
1094 	}
1095 
1096 	in6_ifa_hold(ifa);
1097 	write_unlock(&idev->lock);
1098 
1099 	rcu_read_unlock_bh();
1100 
1101 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1102 out:
1103 	if (unlikely(err < 0)) {
1104 		fib6_info_release(f6i);
1105 
1106 		if (ifa) {
1107 			if (ifa->idev)
1108 				in6_dev_put(ifa->idev);
1109 			kfree(ifa);
1110 		}
1111 		ifa = ERR_PTR(err);
1112 	}
1113 
1114 	return ifa;
1115 }
1116 
1117 enum cleanup_prefix_rt_t {
1118 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1119 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1120 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1121 };
1122 
1123 /*
1124  * Check, whether the prefix for ifp would still need a prefix route
1125  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1126  * constants.
1127  *
1128  * 1) we don't purge prefix if address was not permanent.
1129  *    prefix is managed by its own lifetime.
1130  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1131  * 3) if there are no addresses, delete prefix.
1132  * 4) if there are still other permanent address(es),
1133  *    corresponding prefix is still permanent.
1134  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1135  *    don't purge the prefix, assume user space is managing it.
1136  * 6) otherwise, update prefix lifetime to the
1137  *    longest valid lifetime among the corresponding
1138  *    addresses on the device.
1139  *    Note: subsequent RA will update lifetime.
1140  **/
1141 static enum cleanup_prefix_rt_t
1142 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1143 {
1144 	struct inet6_ifaddr *ifa;
1145 	struct inet6_dev *idev = ifp->idev;
1146 	unsigned long lifetime;
1147 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1148 
1149 	*expires = jiffies;
1150 
1151 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1152 		if (ifa == ifp)
1153 			continue;
1154 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1155 				       ifp->prefix_len))
1156 			continue;
1157 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1158 			return CLEANUP_PREFIX_RT_NOP;
1159 
1160 		action = CLEANUP_PREFIX_RT_EXPIRE;
1161 
1162 		spin_lock(&ifa->lock);
1163 
1164 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1165 		/*
1166 		 * Note: Because this address is
1167 		 * not permanent, lifetime <
1168 		 * LONG_MAX / HZ here.
1169 		 */
1170 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1171 			*expires = ifa->tstamp + lifetime * HZ;
1172 		spin_unlock(&ifa->lock);
1173 	}
1174 
1175 	return action;
1176 }
1177 
1178 static void
1179 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1180 {
1181 	struct fib6_info *f6i;
1182 
1183 	f6i = addrconf_get_prefix_route(&ifp->addr,
1184 				       ifp->prefix_len,
1185 				       ifp->idev->dev,
1186 				       0, RTF_GATEWAY | RTF_DEFAULT);
1187 	if (f6i) {
1188 		if (del_rt)
1189 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1190 		else {
1191 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1192 				fib6_set_expires(f6i, expires);
1193 			fib6_info_release(f6i);
1194 		}
1195 	}
1196 }
1197 
1198 
1199 /* This function wants to get referenced ifp and releases it before return */
1200 
1201 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1202 {
1203 	int state;
1204 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1205 	unsigned long expires;
1206 
1207 	ASSERT_RTNL();
1208 
1209 	spin_lock_bh(&ifp->lock);
1210 	state = ifp->state;
1211 	ifp->state = INET6_IFADDR_STATE_DEAD;
1212 	spin_unlock_bh(&ifp->lock);
1213 
1214 	if (state == INET6_IFADDR_STATE_DEAD)
1215 		goto out;
1216 
1217 	spin_lock_bh(&addrconf_hash_lock);
1218 	hlist_del_init_rcu(&ifp->addr_lst);
1219 	spin_unlock_bh(&addrconf_hash_lock);
1220 
1221 	write_lock_bh(&ifp->idev->lock);
1222 
1223 	if (ifp->flags&IFA_F_TEMPORARY) {
1224 		list_del(&ifp->tmp_list);
1225 		if (ifp->ifpub) {
1226 			in6_ifa_put(ifp->ifpub);
1227 			ifp->ifpub = NULL;
1228 		}
1229 		__in6_ifa_put(ifp);
1230 	}
1231 
1232 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1233 		action = check_cleanup_prefix_route(ifp, &expires);
1234 
1235 	list_del_rcu(&ifp->if_list);
1236 	__in6_ifa_put(ifp);
1237 
1238 	write_unlock_bh(&ifp->idev->lock);
1239 
1240 	addrconf_del_dad_work(ifp);
1241 
1242 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1243 
1244 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1245 
1246 	if (action != CLEANUP_PREFIX_RT_NOP) {
1247 		cleanup_prefix_route(ifp, expires,
1248 			action == CLEANUP_PREFIX_RT_DEL);
1249 	}
1250 
1251 	/* clean up prefsrc entries */
1252 	rt6_remove_prefsrc(ifp);
1253 out:
1254 	in6_ifa_put(ifp);
1255 }
1256 
1257 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1258 				struct inet6_ifaddr *ift,
1259 				bool block)
1260 {
1261 	struct inet6_dev *idev = ifp->idev;
1262 	struct in6_addr addr, *tmpaddr;
1263 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
1264 	unsigned long regen_advance;
1265 	int tmp_plen;
1266 	int ret = 0;
1267 	u32 addr_flags;
1268 	unsigned long now = jiffies;
1269 	long max_desync_factor;
1270 	s32 cnf_temp_preferred_lft;
1271 
1272 	write_lock_bh(&idev->lock);
1273 	if (ift) {
1274 		spin_lock_bh(&ift->lock);
1275 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1276 		spin_unlock_bh(&ift->lock);
1277 		tmpaddr = &addr;
1278 	} else {
1279 		tmpaddr = NULL;
1280 	}
1281 retry:
1282 	in6_dev_hold(idev);
1283 	if (idev->cnf.use_tempaddr <= 0) {
1284 		write_unlock_bh(&idev->lock);
1285 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1286 		in6_dev_put(idev);
1287 		ret = -1;
1288 		goto out;
1289 	}
1290 	spin_lock_bh(&ifp->lock);
1291 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1292 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1293 		spin_unlock_bh(&ifp->lock);
1294 		write_unlock_bh(&idev->lock);
1295 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1296 			__func__);
1297 		in6_dev_put(idev);
1298 		ret = -1;
1299 		goto out;
1300 	}
1301 	in6_ifa_hold(ifp);
1302 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1303 	ipv6_try_regen_rndid(idev, tmpaddr);
1304 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1305 	age = (now - ifp->tstamp) / HZ;
1306 
1307 	regen_advance = idev->cnf.regen_max_retry *
1308 			idev->cnf.dad_transmits *
1309 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1310 
1311 	/* recalculate max_desync_factor each time and update
1312 	 * idev->desync_factor if it's larger
1313 	 */
1314 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1315 	max_desync_factor = min_t(__u32,
1316 				  idev->cnf.max_desync_factor,
1317 				  cnf_temp_preferred_lft - regen_advance);
1318 
1319 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1320 		if (max_desync_factor > 0) {
1321 			get_random_bytes(&idev->desync_factor,
1322 					 sizeof(idev->desync_factor));
1323 			idev->desync_factor %= max_desync_factor;
1324 		} else {
1325 			idev->desync_factor = 0;
1326 		}
1327 	}
1328 
1329 	tmp_valid_lft = min_t(__u32,
1330 			      ifp->valid_lft,
1331 			      idev->cnf.temp_valid_lft + age);
1332 	tmp_prefered_lft = cnf_temp_preferred_lft + age -
1333 			    idev->desync_factor;
1334 	tmp_prefered_lft = min_t(__u32, ifp->prefered_lft, tmp_prefered_lft);
1335 	tmp_plen = ifp->prefix_len;
1336 	tmp_tstamp = ifp->tstamp;
1337 	spin_unlock_bh(&ifp->lock);
1338 
1339 	write_unlock_bh(&idev->lock);
1340 
1341 	/* A temporary address is created only if this calculated Preferred
1342 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1343 	 * an implementation must not create a temporary address with a zero
1344 	 * Preferred Lifetime.
1345 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1346 	 * temporary addresses being generated.
1347 	 */
1348 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1349 	if (tmp_prefered_lft <= regen_advance + age) {
1350 		in6_ifa_put(ifp);
1351 		in6_dev_put(idev);
1352 		ret = -1;
1353 		goto out;
1354 	}
1355 
1356 	addr_flags = IFA_F_TEMPORARY;
1357 	/* set in addrconf_prefix_rcv() */
1358 	if (ifp->flags & IFA_F_OPTIMISTIC)
1359 		addr_flags |= IFA_F_OPTIMISTIC;
1360 
1361 	ift = ipv6_add_addr(idev, &addr, NULL, tmp_plen,
1362 			    ipv6_addr_scope(&addr), addr_flags,
1363 			    tmp_valid_lft, tmp_prefered_lft, block, NULL);
1364 	if (IS_ERR(ift)) {
1365 		in6_ifa_put(ifp);
1366 		in6_dev_put(idev);
1367 		pr_info("%s: retry temporary address regeneration\n", __func__);
1368 		tmpaddr = &addr;
1369 		write_lock_bh(&idev->lock);
1370 		goto retry;
1371 	}
1372 
1373 	spin_lock_bh(&ift->lock);
1374 	ift->ifpub = ifp;
1375 	ift->cstamp = now;
1376 	ift->tstamp = tmp_tstamp;
1377 	spin_unlock_bh(&ift->lock);
1378 
1379 	addrconf_dad_start(ift);
1380 	in6_ifa_put(ift);
1381 	in6_dev_put(idev);
1382 out:
1383 	return ret;
1384 }
1385 
1386 /*
1387  *	Choose an appropriate source address (RFC3484)
1388  */
1389 enum {
1390 	IPV6_SADDR_RULE_INIT = 0,
1391 	IPV6_SADDR_RULE_LOCAL,
1392 	IPV6_SADDR_RULE_SCOPE,
1393 	IPV6_SADDR_RULE_PREFERRED,
1394 #ifdef CONFIG_IPV6_MIP6
1395 	IPV6_SADDR_RULE_HOA,
1396 #endif
1397 	IPV6_SADDR_RULE_OIF,
1398 	IPV6_SADDR_RULE_LABEL,
1399 	IPV6_SADDR_RULE_PRIVACY,
1400 	IPV6_SADDR_RULE_ORCHID,
1401 	IPV6_SADDR_RULE_PREFIX,
1402 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1403 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1404 #endif
1405 	IPV6_SADDR_RULE_MAX
1406 };
1407 
1408 struct ipv6_saddr_score {
1409 	int			rule;
1410 	int			addr_type;
1411 	struct inet6_ifaddr	*ifa;
1412 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1413 	int			scopedist;
1414 	int			matchlen;
1415 };
1416 
1417 struct ipv6_saddr_dst {
1418 	const struct in6_addr *addr;
1419 	int ifindex;
1420 	int scope;
1421 	int label;
1422 	unsigned int prefs;
1423 };
1424 
1425 static inline int ipv6_saddr_preferred(int type)
1426 {
1427 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1428 		return 1;
1429 	return 0;
1430 }
1431 
1432 static bool ipv6_use_optimistic_addr(struct net *net,
1433 				     struct inet6_dev *idev)
1434 {
1435 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1436 	if (!idev)
1437 		return false;
1438 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1439 		return false;
1440 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1441 		return false;
1442 
1443 	return true;
1444 #else
1445 	return false;
1446 #endif
1447 }
1448 
1449 static bool ipv6_allow_optimistic_dad(struct net *net,
1450 				      struct inet6_dev *idev)
1451 {
1452 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1453 	if (!idev)
1454 		return false;
1455 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1456 		return false;
1457 
1458 	return true;
1459 #else
1460 	return false;
1461 #endif
1462 }
1463 
1464 static int ipv6_get_saddr_eval(struct net *net,
1465 			       struct ipv6_saddr_score *score,
1466 			       struct ipv6_saddr_dst *dst,
1467 			       int i)
1468 {
1469 	int ret;
1470 
1471 	if (i <= score->rule) {
1472 		switch (i) {
1473 		case IPV6_SADDR_RULE_SCOPE:
1474 			ret = score->scopedist;
1475 			break;
1476 		case IPV6_SADDR_RULE_PREFIX:
1477 			ret = score->matchlen;
1478 			break;
1479 		default:
1480 			ret = !!test_bit(i, score->scorebits);
1481 		}
1482 		goto out;
1483 	}
1484 
1485 	switch (i) {
1486 	case IPV6_SADDR_RULE_INIT:
1487 		/* Rule 0: remember if hiscore is not ready yet */
1488 		ret = !!score->ifa;
1489 		break;
1490 	case IPV6_SADDR_RULE_LOCAL:
1491 		/* Rule 1: Prefer same address */
1492 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1493 		break;
1494 	case IPV6_SADDR_RULE_SCOPE:
1495 		/* Rule 2: Prefer appropriate scope
1496 		 *
1497 		 *      ret
1498 		 *       ^
1499 		 *    -1 |  d 15
1500 		 *    ---+--+-+---> scope
1501 		 *       |
1502 		 *       |             d is scope of the destination.
1503 		 *  B-d  |  \
1504 		 *       |   \      <- smaller scope is better if
1505 		 *  B-15 |    \        if scope is enough for destination.
1506 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1507 		 * d-C-1 | /
1508 		 *       |/         <- greater is better
1509 		 *   -C  /             if scope is not enough for destination.
1510 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1511 		 *
1512 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1513 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1514 		 * Assume B = 0 and we get C > 29.
1515 		 */
1516 		ret = __ipv6_addr_src_scope(score->addr_type);
1517 		if (ret >= dst->scope)
1518 			ret = -ret;
1519 		else
1520 			ret -= 128;	/* 30 is enough */
1521 		score->scopedist = ret;
1522 		break;
1523 	case IPV6_SADDR_RULE_PREFERRED:
1524 	    {
1525 		/* Rule 3: Avoid deprecated and optimistic addresses */
1526 		u8 avoid = IFA_F_DEPRECATED;
1527 
1528 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1529 			avoid |= IFA_F_OPTIMISTIC;
1530 		ret = ipv6_saddr_preferred(score->addr_type) ||
1531 		      !(score->ifa->flags & avoid);
1532 		break;
1533 	    }
1534 #ifdef CONFIG_IPV6_MIP6
1535 	case IPV6_SADDR_RULE_HOA:
1536 	    {
1537 		/* Rule 4: Prefer home address */
1538 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1539 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1540 		break;
1541 	    }
1542 #endif
1543 	case IPV6_SADDR_RULE_OIF:
1544 		/* Rule 5: Prefer outgoing interface */
1545 		ret = (!dst->ifindex ||
1546 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1547 		break;
1548 	case IPV6_SADDR_RULE_LABEL:
1549 		/* Rule 6: Prefer matching label */
1550 		ret = ipv6_addr_label(net,
1551 				      &score->ifa->addr, score->addr_type,
1552 				      score->ifa->idev->dev->ifindex) == dst->label;
1553 		break;
1554 	case IPV6_SADDR_RULE_PRIVACY:
1555 	    {
1556 		/* Rule 7: Prefer public address
1557 		 * Note: prefer temporary address if use_tempaddr >= 2
1558 		 */
1559 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1560 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1561 				score->ifa->idev->cnf.use_tempaddr >= 2;
1562 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1563 		break;
1564 	    }
1565 	case IPV6_SADDR_RULE_ORCHID:
1566 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1567 		 *	    non-ORCHID vs non-ORCHID
1568 		 */
1569 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1570 			ipv6_addr_orchid(dst->addr));
1571 		break;
1572 	case IPV6_SADDR_RULE_PREFIX:
1573 		/* Rule 8: Use longest matching prefix */
1574 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1575 		if (ret > score->ifa->prefix_len)
1576 			ret = score->ifa->prefix_len;
1577 		score->matchlen = ret;
1578 		break;
1579 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1580 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1581 		/* Optimistic addresses still have lower precedence than other
1582 		 * preferred addresses.
1583 		 */
1584 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1585 		break;
1586 #endif
1587 	default:
1588 		ret = 0;
1589 	}
1590 
1591 	if (ret)
1592 		__set_bit(i, score->scorebits);
1593 	score->rule = i;
1594 out:
1595 	return ret;
1596 }
1597 
1598 static int __ipv6_dev_get_saddr(struct net *net,
1599 				struct ipv6_saddr_dst *dst,
1600 				struct inet6_dev *idev,
1601 				struct ipv6_saddr_score *scores,
1602 				int hiscore_idx)
1603 {
1604 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1605 
1606 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1607 		int i;
1608 
1609 		/*
1610 		 * - Tentative Address (RFC2462 section 5.4)
1611 		 *  - A tentative address is not considered
1612 		 *    "assigned to an interface" in the traditional
1613 		 *    sense, unless it is also flagged as optimistic.
1614 		 * - Candidate Source Address (section 4)
1615 		 *  - In any case, anycast addresses, multicast
1616 		 *    addresses, and the unspecified address MUST
1617 		 *    NOT be included in a candidate set.
1618 		 */
1619 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1620 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1621 			continue;
1622 
1623 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1624 
1625 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1626 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1627 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1628 					    idev->dev->name);
1629 			continue;
1630 		}
1631 
1632 		score->rule = -1;
1633 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1634 
1635 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1636 			int minihiscore, miniscore;
1637 
1638 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1639 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1640 
1641 			if (minihiscore > miniscore) {
1642 				if (i == IPV6_SADDR_RULE_SCOPE &&
1643 				    score->scopedist > 0) {
1644 					/*
1645 					 * special case:
1646 					 * each remaining entry
1647 					 * has too small (not enough)
1648 					 * scope, because ifa entries
1649 					 * are sorted by their scope
1650 					 * values.
1651 					 */
1652 					goto out;
1653 				}
1654 				break;
1655 			} else if (minihiscore < miniscore) {
1656 				swap(hiscore, score);
1657 				hiscore_idx = 1 - hiscore_idx;
1658 
1659 				/* restore our iterator */
1660 				score->ifa = hiscore->ifa;
1661 
1662 				break;
1663 			}
1664 		}
1665 	}
1666 out:
1667 	return hiscore_idx;
1668 }
1669 
1670 static int ipv6_get_saddr_master(struct net *net,
1671 				 const struct net_device *dst_dev,
1672 				 const struct net_device *master,
1673 				 struct ipv6_saddr_dst *dst,
1674 				 struct ipv6_saddr_score *scores,
1675 				 int hiscore_idx)
1676 {
1677 	struct inet6_dev *idev;
1678 
1679 	idev = __in6_dev_get(dst_dev);
1680 	if (idev)
1681 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1682 						   scores, hiscore_idx);
1683 
1684 	idev = __in6_dev_get(master);
1685 	if (idev)
1686 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1687 						   scores, hiscore_idx);
1688 
1689 	return hiscore_idx;
1690 }
1691 
1692 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1693 		       const struct in6_addr *daddr, unsigned int prefs,
1694 		       struct in6_addr *saddr)
1695 {
1696 	struct ipv6_saddr_score scores[2], *hiscore;
1697 	struct ipv6_saddr_dst dst;
1698 	struct inet6_dev *idev;
1699 	struct net_device *dev;
1700 	int dst_type;
1701 	bool use_oif_addr = false;
1702 	int hiscore_idx = 0;
1703 	int ret = 0;
1704 
1705 	dst_type = __ipv6_addr_type(daddr);
1706 	dst.addr = daddr;
1707 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1708 	dst.scope = __ipv6_addr_src_scope(dst_type);
1709 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1710 	dst.prefs = prefs;
1711 
1712 	scores[hiscore_idx].rule = -1;
1713 	scores[hiscore_idx].ifa = NULL;
1714 
1715 	rcu_read_lock();
1716 
1717 	/* Candidate Source Address (section 4)
1718 	 *  - multicast and link-local destination address,
1719 	 *    the set of candidate source address MUST only
1720 	 *    include addresses assigned to interfaces
1721 	 *    belonging to the same link as the outgoing
1722 	 *    interface.
1723 	 * (- For site-local destination addresses, the
1724 	 *    set of candidate source addresses MUST only
1725 	 *    include addresses assigned to interfaces
1726 	 *    belonging to the same site as the outgoing
1727 	 *    interface.)
1728 	 *  - "It is RECOMMENDED that the candidate source addresses
1729 	 *    be the set of unicast addresses assigned to the
1730 	 *    interface that will be used to send to the destination
1731 	 *    (the 'outgoing' interface)." (RFC 6724)
1732 	 */
1733 	if (dst_dev) {
1734 		idev = __in6_dev_get(dst_dev);
1735 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1736 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1737 		    (idev && idev->cnf.use_oif_addrs_only)) {
1738 			use_oif_addr = true;
1739 		}
1740 	}
1741 
1742 	if (use_oif_addr) {
1743 		if (idev)
1744 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1745 	} else {
1746 		const struct net_device *master;
1747 		int master_idx = 0;
1748 
1749 		/* if dst_dev exists and is enslaved to an L3 device, then
1750 		 * prefer addresses from dst_dev and then the master over
1751 		 * any other enslaved devices in the L3 domain.
1752 		 */
1753 		master = l3mdev_master_dev_rcu(dst_dev);
1754 		if (master) {
1755 			master_idx = master->ifindex;
1756 
1757 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1758 							    master, &dst,
1759 							    scores, hiscore_idx);
1760 
1761 			if (scores[hiscore_idx].ifa)
1762 				goto out;
1763 		}
1764 
1765 		for_each_netdev_rcu(net, dev) {
1766 			/* only consider addresses on devices in the
1767 			 * same L3 domain
1768 			 */
1769 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1770 				continue;
1771 			idev = __in6_dev_get(dev);
1772 			if (!idev)
1773 				continue;
1774 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1775 		}
1776 	}
1777 
1778 out:
1779 	hiscore = &scores[hiscore_idx];
1780 	if (!hiscore->ifa)
1781 		ret = -EADDRNOTAVAIL;
1782 	else
1783 		*saddr = hiscore->ifa->addr;
1784 
1785 	rcu_read_unlock();
1786 	return ret;
1787 }
1788 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1789 
1790 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1791 		      u32 banned_flags)
1792 {
1793 	struct inet6_ifaddr *ifp;
1794 	int err = -EADDRNOTAVAIL;
1795 
1796 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1797 		if (ifp->scope > IFA_LINK)
1798 			break;
1799 		if (ifp->scope == IFA_LINK &&
1800 		    !(ifp->flags & banned_flags)) {
1801 			*addr = ifp->addr;
1802 			err = 0;
1803 			break;
1804 		}
1805 	}
1806 	return err;
1807 }
1808 
1809 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1810 		    u32 banned_flags)
1811 {
1812 	struct inet6_dev *idev;
1813 	int err = -EADDRNOTAVAIL;
1814 
1815 	rcu_read_lock();
1816 	idev = __in6_dev_get(dev);
1817 	if (idev) {
1818 		read_lock_bh(&idev->lock);
1819 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1820 		read_unlock_bh(&idev->lock);
1821 	}
1822 	rcu_read_unlock();
1823 	return err;
1824 }
1825 
1826 static int ipv6_count_addresses(const struct inet6_dev *idev)
1827 {
1828 	const struct inet6_ifaddr *ifp;
1829 	int cnt = 0;
1830 
1831 	rcu_read_lock();
1832 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1833 		cnt++;
1834 	rcu_read_unlock();
1835 	return cnt;
1836 }
1837 
1838 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1839 		  const struct net_device *dev, int strict)
1840 {
1841 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1842 				       strict, IFA_F_TENTATIVE);
1843 }
1844 EXPORT_SYMBOL(ipv6_chk_addr);
1845 
1846 /* device argument is used to find the L3 domain of interest. If
1847  * skip_dev_check is set, then the ifp device is not checked against
1848  * the passed in dev argument. So the 2 cases for addresses checks are:
1849  *   1. does the address exist in the L3 domain that dev is part of
1850  *      (skip_dev_check = true), or
1851  *
1852  *   2. does the address exist on the specific device
1853  *      (skip_dev_check = false)
1854  */
1855 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1856 			    const struct net_device *dev, bool skip_dev_check,
1857 			    int strict, u32 banned_flags)
1858 {
1859 	unsigned int hash = inet6_addr_hash(net, addr);
1860 	const struct net_device *l3mdev;
1861 	struct inet6_ifaddr *ifp;
1862 	u32 ifp_flags;
1863 
1864 	rcu_read_lock();
1865 
1866 	l3mdev = l3mdev_master_dev_rcu(dev);
1867 	if (skip_dev_check)
1868 		dev = NULL;
1869 
1870 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1871 		if (!net_eq(dev_net(ifp->idev->dev), net))
1872 			continue;
1873 
1874 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1875 			continue;
1876 
1877 		/* Decouple optimistic from tentative for evaluation here.
1878 		 * Ban optimistic addresses explicitly, when required.
1879 		 */
1880 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1881 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1882 			    : ifp->flags;
1883 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1884 		    !(ifp_flags&banned_flags) &&
1885 		    (!dev || ifp->idev->dev == dev ||
1886 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1887 			rcu_read_unlock();
1888 			return 1;
1889 		}
1890 	}
1891 
1892 	rcu_read_unlock();
1893 	return 0;
1894 }
1895 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1896 
1897 
1898 /* Compares an address/prefix_len with addresses on device @dev.
1899  * If one is found it returns true.
1900  */
1901 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1902 	const unsigned int prefix_len, struct net_device *dev)
1903 {
1904 	const struct inet6_ifaddr *ifa;
1905 	const struct inet6_dev *idev;
1906 	bool ret = false;
1907 
1908 	rcu_read_lock();
1909 	idev = __in6_dev_get(dev);
1910 	if (idev) {
1911 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1912 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1913 			if (ret)
1914 				break;
1915 		}
1916 	}
1917 	rcu_read_unlock();
1918 
1919 	return ret;
1920 }
1921 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1922 
1923 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1924 {
1925 	const struct inet6_ifaddr *ifa;
1926 	const struct inet6_dev *idev;
1927 	int	onlink;
1928 
1929 	onlink = 0;
1930 	rcu_read_lock();
1931 	idev = __in6_dev_get(dev);
1932 	if (idev) {
1933 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1934 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1935 						   ifa->prefix_len);
1936 			if (onlink)
1937 				break;
1938 		}
1939 	}
1940 	rcu_read_unlock();
1941 	return onlink;
1942 }
1943 EXPORT_SYMBOL(ipv6_chk_prefix);
1944 
1945 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1946 				     struct net_device *dev, int strict)
1947 {
1948 	unsigned int hash = inet6_addr_hash(net, addr);
1949 	struct inet6_ifaddr *ifp, *result = NULL;
1950 
1951 	rcu_read_lock();
1952 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1953 		if (!net_eq(dev_net(ifp->idev->dev), net))
1954 			continue;
1955 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1956 			if (!dev || ifp->idev->dev == dev ||
1957 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1958 				result = ifp;
1959 				in6_ifa_hold(ifp);
1960 				break;
1961 			}
1962 		}
1963 	}
1964 	rcu_read_unlock();
1965 
1966 	return result;
1967 }
1968 
1969 /* Gets referenced address, destroys ifaddr */
1970 
1971 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1972 {
1973 	if (dad_failed)
1974 		ifp->flags |= IFA_F_DADFAILED;
1975 
1976 	if (ifp->flags&IFA_F_TEMPORARY) {
1977 		struct inet6_ifaddr *ifpub;
1978 		spin_lock_bh(&ifp->lock);
1979 		ifpub = ifp->ifpub;
1980 		if (ifpub) {
1981 			in6_ifa_hold(ifpub);
1982 			spin_unlock_bh(&ifp->lock);
1983 			ipv6_create_tempaddr(ifpub, ifp, true);
1984 			in6_ifa_put(ifpub);
1985 		} else {
1986 			spin_unlock_bh(&ifp->lock);
1987 		}
1988 		ipv6_del_addr(ifp);
1989 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1990 		spin_lock_bh(&ifp->lock);
1991 		addrconf_del_dad_work(ifp);
1992 		ifp->flags |= IFA_F_TENTATIVE;
1993 		if (dad_failed)
1994 			ifp->flags &= ~IFA_F_OPTIMISTIC;
1995 		spin_unlock_bh(&ifp->lock);
1996 		if (dad_failed)
1997 			ipv6_ifa_notify(0, ifp);
1998 		in6_ifa_put(ifp);
1999 	} else {
2000 		ipv6_del_addr(ifp);
2001 	}
2002 }
2003 
2004 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2005 {
2006 	int err = -ENOENT;
2007 
2008 	spin_lock_bh(&ifp->lock);
2009 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2010 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2011 		err = 0;
2012 	}
2013 	spin_unlock_bh(&ifp->lock);
2014 
2015 	return err;
2016 }
2017 
2018 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2019 {
2020 	struct inet6_dev *idev = ifp->idev;
2021 	struct net *net = dev_net(ifp->idev->dev);
2022 
2023 	if (addrconf_dad_end(ifp)) {
2024 		in6_ifa_put(ifp);
2025 		return;
2026 	}
2027 
2028 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2029 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2030 
2031 	spin_lock_bh(&ifp->lock);
2032 
2033 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2034 		int scope = ifp->scope;
2035 		u32 flags = ifp->flags;
2036 		struct in6_addr new_addr;
2037 		struct inet6_ifaddr *ifp2;
2038 		u32 valid_lft, preferred_lft;
2039 		int pfxlen = ifp->prefix_len;
2040 		int retries = ifp->stable_privacy_retry + 1;
2041 
2042 		if (retries > net->ipv6.sysctl.idgen_retries) {
2043 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2044 					     ifp->idev->dev->name);
2045 			goto errdad;
2046 		}
2047 
2048 		new_addr = ifp->addr;
2049 		if (ipv6_generate_stable_address(&new_addr, retries,
2050 						 idev))
2051 			goto errdad;
2052 
2053 		valid_lft = ifp->valid_lft;
2054 		preferred_lft = ifp->prefered_lft;
2055 
2056 		spin_unlock_bh(&ifp->lock);
2057 
2058 		if (idev->cnf.max_addresses &&
2059 		    ipv6_count_addresses(idev) >=
2060 		    idev->cnf.max_addresses)
2061 			goto lock_errdad;
2062 
2063 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2064 				     ifp->idev->dev->name);
2065 
2066 		ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen,
2067 				     scope, flags, valid_lft,
2068 				     preferred_lft, false, NULL);
2069 		if (IS_ERR(ifp2))
2070 			goto lock_errdad;
2071 
2072 		spin_lock_bh(&ifp2->lock);
2073 		ifp2->stable_privacy_retry = retries;
2074 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2075 		spin_unlock_bh(&ifp2->lock);
2076 
2077 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2078 		in6_ifa_put(ifp2);
2079 lock_errdad:
2080 		spin_lock_bh(&ifp->lock);
2081 	}
2082 
2083 errdad:
2084 	/* transition from _POSTDAD to _ERRDAD */
2085 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2086 	spin_unlock_bh(&ifp->lock);
2087 
2088 	addrconf_mod_dad_work(ifp, 0);
2089 	in6_ifa_put(ifp);
2090 }
2091 
2092 /* Join to solicited addr multicast group.
2093  * caller must hold RTNL */
2094 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2095 {
2096 	struct in6_addr maddr;
2097 
2098 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2099 		return;
2100 
2101 	addrconf_addr_solict_mult(addr, &maddr);
2102 	ipv6_dev_mc_inc(dev, &maddr);
2103 }
2104 
2105 /* caller must hold RTNL */
2106 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2107 {
2108 	struct in6_addr maddr;
2109 
2110 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2111 		return;
2112 
2113 	addrconf_addr_solict_mult(addr, &maddr);
2114 	__ipv6_dev_mc_dec(idev, &maddr);
2115 }
2116 
2117 /* caller must hold RTNL */
2118 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2119 {
2120 	struct in6_addr addr;
2121 
2122 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2123 		return;
2124 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2125 	if (ipv6_addr_any(&addr))
2126 		return;
2127 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2128 }
2129 
2130 /* caller must hold RTNL */
2131 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2132 {
2133 	struct in6_addr addr;
2134 
2135 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2136 		return;
2137 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2138 	if (ipv6_addr_any(&addr))
2139 		return;
2140 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2141 }
2142 
2143 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2144 {
2145 	switch (dev->addr_len) {
2146 	case ETH_ALEN:
2147 		memcpy(eui, dev->dev_addr, 3);
2148 		eui[3] = 0xFF;
2149 		eui[4] = 0xFE;
2150 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2151 		break;
2152 	case EUI64_ADDR_LEN:
2153 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2154 		eui[0] ^= 2;
2155 		break;
2156 	default:
2157 		return -1;
2158 	}
2159 
2160 	return 0;
2161 }
2162 
2163 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2164 {
2165 	union fwnet_hwaddr *ha;
2166 
2167 	if (dev->addr_len != FWNET_ALEN)
2168 		return -1;
2169 
2170 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2171 
2172 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2173 	eui[0] ^= 2;
2174 	return 0;
2175 }
2176 
2177 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2178 {
2179 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2180 	if (dev->addr_len != ARCNET_ALEN)
2181 		return -1;
2182 	memset(eui, 0, 7);
2183 	eui[7] = *(u8 *)dev->dev_addr;
2184 	return 0;
2185 }
2186 
2187 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2188 {
2189 	if (dev->addr_len != INFINIBAND_ALEN)
2190 		return -1;
2191 	memcpy(eui, dev->dev_addr + 12, 8);
2192 	eui[0] |= 2;
2193 	return 0;
2194 }
2195 
2196 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2197 {
2198 	if (addr == 0)
2199 		return -1;
2200 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2201 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2202 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2203 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2204 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2205 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2206 	eui[1] = 0;
2207 	eui[2] = 0x5E;
2208 	eui[3] = 0xFE;
2209 	memcpy(eui + 4, &addr, 4);
2210 	return 0;
2211 }
2212 
2213 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2214 {
2215 	if (dev->priv_flags & IFF_ISATAP)
2216 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2217 	return -1;
2218 }
2219 
2220 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2221 {
2222 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2223 }
2224 
2225 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2226 {
2227 	memcpy(eui, dev->perm_addr, 3);
2228 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2229 	eui[3] = 0xFF;
2230 	eui[4] = 0xFE;
2231 	eui[0] ^= 2;
2232 	return 0;
2233 }
2234 
2235 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2236 {
2237 	switch (dev->type) {
2238 	case ARPHRD_ETHER:
2239 	case ARPHRD_FDDI:
2240 		return addrconf_ifid_eui48(eui, dev);
2241 	case ARPHRD_ARCNET:
2242 		return addrconf_ifid_arcnet(eui, dev);
2243 	case ARPHRD_INFINIBAND:
2244 		return addrconf_ifid_infiniband(eui, dev);
2245 	case ARPHRD_SIT:
2246 		return addrconf_ifid_sit(eui, dev);
2247 	case ARPHRD_IPGRE:
2248 	case ARPHRD_TUNNEL:
2249 		return addrconf_ifid_gre(eui, dev);
2250 	case ARPHRD_6LOWPAN:
2251 		return addrconf_ifid_6lowpan(eui, dev);
2252 	case ARPHRD_IEEE1394:
2253 		return addrconf_ifid_ieee1394(eui, dev);
2254 	case ARPHRD_TUNNEL6:
2255 	case ARPHRD_IP6GRE:
2256 		return addrconf_ifid_ip6tnl(eui, dev);
2257 	}
2258 	return -1;
2259 }
2260 
2261 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2262 {
2263 	int err = -1;
2264 	struct inet6_ifaddr *ifp;
2265 
2266 	read_lock_bh(&idev->lock);
2267 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2268 		if (ifp->scope > IFA_LINK)
2269 			break;
2270 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2271 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2272 			err = 0;
2273 			break;
2274 		}
2275 	}
2276 	read_unlock_bh(&idev->lock);
2277 	return err;
2278 }
2279 
2280 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2281 static void ipv6_regen_rndid(struct inet6_dev *idev)
2282 {
2283 regen:
2284 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2285 	idev->rndid[0] &= ~0x02;
2286 
2287 	/*
2288 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2289 	 * check if generated address is not inappropriate
2290 	 *
2291 	 *  - Reserved subnet anycast (RFC 2526)
2292 	 *	11111101 11....11 1xxxxxxx
2293 	 *  - ISATAP (RFC4214) 6.1
2294 	 *	00-00-5E-FE-xx-xx-xx-xx
2295 	 *  - value 0
2296 	 *  - XXX: already assigned to an address on the device
2297 	 */
2298 	if (idev->rndid[0] == 0xfd &&
2299 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2300 	    (idev->rndid[7]&0x80))
2301 		goto regen;
2302 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2303 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2304 			goto regen;
2305 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2306 			goto regen;
2307 	}
2308 }
2309 
2310 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2311 {
2312 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2313 		ipv6_regen_rndid(idev);
2314 }
2315 
2316 /*
2317  *	Add prefix route.
2318  */
2319 
2320 static void
2321 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
2322 		      unsigned long expires, u32 flags, gfp_t gfp_flags)
2323 {
2324 	struct fib6_config cfg = {
2325 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2326 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2327 		.fc_ifindex = dev->ifindex,
2328 		.fc_expires = expires,
2329 		.fc_dst_len = plen,
2330 		.fc_flags = RTF_UP | flags,
2331 		.fc_nlinfo.nl_net = dev_net(dev),
2332 		.fc_protocol = RTPROT_KERNEL,
2333 		.fc_type = RTN_UNICAST,
2334 	};
2335 
2336 	cfg.fc_dst = *pfx;
2337 
2338 	/* Prevent useless cloning on PtP SIT.
2339 	   This thing is done here expecting that the whole
2340 	   class of non-broadcast devices need not cloning.
2341 	 */
2342 #if IS_ENABLED(CONFIG_IPV6_SIT)
2343 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2344 		cfg.fc_flags |= RTF_NONEXTHOP;
2345 #endif
2346 
2347 	ip6_route_add(&cfg, gfp_flags, NULL);
2348 }
2349 
2350 
2351 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2352 						  int plen,
2353 						  const struct net_device *dev,
2354 						  u32 flags, u32 noflags)
2355 {
2356 	struct fib6_node *fn;
2357 	struct fib6_info *rt = NULL;
2358 	struct fib6_table *table;
2359 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2360 
2361 	table = fib6_get_table(dev_net(dev), tb_id);
2362 	if (!table)
2363 		return NULL;
2364 
2365 	rcu_read_lock();
2366 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2367 	if (!fn)
2368 		goto out;
2369 
2370 	for_each_fib6_node_rt_rcu(fn) {
2371 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
2372 			continue;
2373 		if ((rt->fib6_flags & flags) != flags)
2374 			continue;
2375 		if ((rt->fib6_flags & noflags) != 0)
2376 			continue;
2377 		fib6_info_hold(rt);
2378 		break;
2379 	}
2380 out:
2381 	rcu_read_unlock();
2382 	return rt;
2383 }
2384 
2385 
2386 /* Create "default" multicast route to the interface */
2387 
2388 static void addrconf_add_mroute(struct net_device *dev)
2389 {
2390 	struct fib6_config cfg = {
2391 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2392 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2393 		.fc_ifindex = dev->ifindex,
2394 		.fc_dst_len = 8,
2395 		.fc_flags = RTF_UP,
2396 		.fc_type = RTN_UNICAST,
2397 		.fc_nlinfo.nl_net = dev_net(dev),
2398 	};
2399 
2400 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2401 
2402 	ip6_route_add(&cfg, GFP_ATOMIC, NULL);
2403 }
2404 
2405 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2406 {
2407 	struct inet6_dev *idev;
2408 
2409 	ASSERT_RTNL();
2410 
2411 	idev = ipv6_find_idev(dev);
2412 	if (!idev)
2413 		return ERR_PTR(-ENOBUFS);
2414 
2415 	if (idev->cnf.disable_ipv6)
2416 		return ERR_PTR(-EACCES);
2417 
2418 	/* Add default multicast route */
2419 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2420 		addrconf_add_mroute(dev);
2421 
2422 	return idev;
2423 }
2424 
2425 static void manage_tempaddrs(struct inet6_dev *idev,
2426 			     struct inet6_ifaddr *ifp,
2427 			     __u32 valid_lft, __u32 prefered_lft,
2428 			     bool create, unsigned long now)
2429 {
2430 	u32 flags;
2431 	struct inet6_ifaddr *ift;
2432 
2433 	read_lock_bh(&idev->lock);
2434 	/* update all temporary addresses in the list */
2435 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2436 		int age, max_valid, max_prefered;
2437 
2438 		if (ifp != ift->ifpub)
2439 			continue;
2440 
2441 		/* RFC 4941 section 3.3:
2442 		 * If a received option will extend the lifetime of a public
2443 		 * address, the lifetimes of temporary addresses should
2444 		 * be extended, subject to the overall constraint that no
2445 		 * temporary addresses should ever remain "valid" or "preferred"
2446 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2447 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2448 		 */
2449 		age = (now - ift->cstamp) / HZ;
2450 		max_valid = idev->cnf.temp_valid_lft - age;
2451 		if (max_valid < 0)
2452 			max_valid = 0;
2453 
2454 		max_prefered = idev->cnf.temp_prefered_lft -
2455 			       idev->desync_factor - age;
2456 		if (max_prefered < 0)
2457 			max_prefered = 0;
2458 
2459 		if (valid_lft > max_valid)
2460 			valid_lft = max_valid;
2461 
2462 		if (prefered_lft > max_prefered)
2463 			prefered_lft = max_prefered;
2464 
2465 		spin_lock(&ift->lock);
2466 		flags = ift->flags;
2467 		ift->valid_lft = valid_lft;
2468 		ift->prefered_lft = prefered_lft;
2469 		ift->tstamp = now;
2470 		if (prefered_lft > 0)
2471 			ift->flags &= ~IFA_F_DEPRECATED;
2472 
2473 		spin_unlock(&ift->lock);
2474 		if (!(flags&IFA_F_TENTATIVE))
2475 			ipv6_ifa_notify(0, ift);
2476 	}
2477 
2478 	if ((create || list_empty(&idev->tempaddr_list)) &&
2479 	    idev->cnf.use_tempaddr > 0) {
2480 		/* When a new public address is created as described
2481 		 * in [ADDRCONF], also create a new temporary address.
2482 		 * Also create a temporary address if it's enabled but
2483 		 * no temporary address currently exists.
2484 		 */
2485 		read_unlock_bh(&idev->lock);
2486 		ipv6_create_tempaddr(ifp, NULL, false);
2487 	} else {
2488 		read_unlock_bh(&idev->lock);
2489 	}
2490 }
2491 
2492 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2493 {
2494 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2495 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2496 }
2497 
2498 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2499 				 const struct prefix_info *pinfo,
2500 				 struct inet6_dev *in6_dev,
2501 				 const struct in6_addr *addr, int addr_type,
2502 				 u32 addr_flags, bool sllao, bool tokenized,
2503 				 __u32 valid_lft, u32 prefered_lft)
2504 {
2505 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2506 	int create = 0, update_lft = 0;
2507 
2508 	if (!ifp && valid_lft) {
2509 		int max_addresses = in6_dev->cnf.max_addresses;
2510 
2511 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2512 		if ((net->ipv6.devconf_all->optimistic_dad ||
2513 		     in6_dev->cnf.optimistic_dad) &&
2514 		    !net->ipv6.devconf_all->forwarding && sllao)
2515 			addr_flags |= IFA_F_OPTIMISTIC;
2516 #endif
2517 
2518 		/* Do not allow to create too much of autoconfigured
2519 		 * addresses; this would be too easy way to crash kernel.
2520 		 */
2521 		if (!max_addresses ||
2522 		    ipv6_count_addresses(in6_dev) < max_addresses)
2523 			ifp = ipv6_add_addr(in6_dev, addr, NULL,
2524 					    pinfo->prefix_len,
2525 					    addr_type&IPV6_ADDR_SCOPE_MASK,
2526 					    addr_flags, valid_lft,
2527 					    prefered_lft, false, NULL);
2528 
2529 		if (IS_ERR_OR_NULL(ifp))
2530 			return -1;
2531 
2532 		create = 1;
2533 		spin_lock_bh(&ifp->lock);
2534 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2535 		ifp->cstamp = jiffies;
2536 		ifp->tokenized = tokenized;
2537 		spin_unlock_bh(&ifp->lock);
2538 		addrconf_dad_start(ifp);
2539 	}
2540 
2541 	if (ifp) {
2542 		u32 flags;
2543 		unsigned long now;
2544 		u32 stored_lft;
2545 
2546 		/* update lifetime (RFC2462 5.5.3 e) */
2547 		spin_lock_bh(&ifp->lock);
2548 		now = jiffies;
2549 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2550 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2551 		else
2552 			stored_lft = 0;
2553 		if (!create && stored_lft) {
2554 			const u32 minimum_lft = min_t(u32,
2555 				stored_lft, MIN_VALID_LIFETIME);
2556 			valid_lft = max(valid_lft, minimum_lft);
2557 
2558 			/* RFC4862 Section 5.5.3e:
2559 			 * "Note that the preferred lifetime of the
2560 			 *  corresponding address is always reset to
2561 			 *  the Preferred Lifetime in the received
2562 			 *  Prefix Information option, regardless of
2563 			 *  whether the valid lifetime is also reset or
2564 			 *  ignored."
2565 			 *
2566 			 * So we should always update prefered_lft here.
2567 			 */
2568 			update_lft = 1;
2569 		}
2570 
2571 		if (update_lft) {
2572 			ifp->valid_lft = valid_lft;
2573 			ifp->prefered_lft = prefered_lft;
2574 			ifp->tstamp = now;
2575 			flags = ifp->flags;
2576 			ifp->flags &= ~IFA_F_DEPRECATED;
2577 			spin_unlock_bh(&ifp->lock);
2578 
2579 			if (!(flags&IFA_F_TENTATIVE))
2580 				ipv6_ifa_notify(0, ifp);
2581 		} else
2582 			spin_unlock_bh(&ifp->lock);
2583 
2584 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2585 				 create, now);
2586 
2587 		in6_ifa_put(ifp);
2588 		addrconf_verify();
2589 	}
2590 
2591 	return 0;
2592 }
2593 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2594 
2595 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2596 {
2597 	struct prefix_info *pinfo;
2598 	__u32 valid_lft;
2599 	__u32 prefered_lft;
2600 	int addr_type, err;
2601 	u32 addr_flags = 0;
2602 	struct inet6_dev *in6_dev;
2603 	struct net *net = dev_net(dev);
2604 
2605 	pinfo = (struct prefix_info *) opt;
2606 
2607 	if (len < sizeof(struct prefix_info)) {
2608 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2609 		return;
2610 	}
2611 
2612 	/*
2613 	 *	Validation checks ([ADDRCONF], page 19)
2614 	 */
2615 
2616 	addr_type = ipv6_addr_type(&pinfo->prefix);
2617 
2618 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2619 		return;
2620 
2621 	valid_lft = ntohl(pinfo->valid);
2622 	prefered_lft = ntohl(pinfo->prefered);
2623 
2624 	if (prefered_lft > valid_lft) {
2625 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2626 		return;
2627 	}
2628 
2629 	in6_dev = in6_dev_get(dev);
2630 
2631 	if (!in6_dev) {
2632 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2633 				    dev->name);
2634 		return;
2635 	}
2636 
2637 	/*
2638 	 *	Two things going on here:
2639 	 *	1) Add routes for on-link prefixes
2640 	 *	2) Configure prefixes with the auto flag set
2641 	 */
2642 
2643 	if (pinfo->onlink) {
2644 		struct fib6_info *rt;
2645 		unsigned long rt_expires;
2646 
2647 		/* Avoid arithmetic overflow. Really, we could
2648 		 * save rt_expires in seconds, likely valid_lft,
2649 		 * but it would require division in fib gc, that it
2650 		 * not good.
2651 		 */
2652 		if (HZ > USER_HZ)
2653 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2654 		else
2655 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2656 
2657 		if (addrconf_finite_timeout(rt_expires))
2658 			rt_expires *= HZ;
2659 
2660 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2661 					       pinfo->prefix_len,
2662 					       dev,
2663 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2664 					       RTF_GATEWAY | RTF_DEFAULT);
2665 
2666 		if (rt) {
2667 			/* Autoconf prefix route */
2668 			if (valid_lft == 0) {
2669 				ip6_del_rt(net, rt);
2670 				rt = NULL;
2671 			} else if (addrconf_finite_timeout(rt_expires)) {
2672 				/* not infinity */
2673 				fib6_set_expires(rt, jiffies + rt_expires);
2674 			} else {
2675 				fib6_clean_expires(rt);
2676 			}
2677 		} else if (valid_lft) {
2678 			clock_t expires = 0;
2679 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2680 			if (addrconf_finite_timeout(rt_expires)) {
2681 				/* not infinity */
2682 				flags |= RTF_EXPIRES;
2683 				expires = jiffies_to_clock_t(rt_expires);
2684 			}
2685 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2686 					      dev, expires, flags, GFP_ATOMIC);
2687 		}
2688 		fib6_info_release(rt);
2689 	}
2690 
2691 	/* Try to figure out our local address for this prefix */
2692 
2693 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2694 		struct in6_addr addr;
2695 		bool tokenized = false, dev_addr_generated = false;
2696 
2697 		if (pinfo->prefix_len == 64) {
2698 			memcpy(&addr, &pinfo->prefix, 8);
2699 
2700 			if (!ipv6_addr_any(&in6_dev->token)) {
2701 				read_lock_bh(&in6_dev->lock);
2702 				memcpy(addr.s6_addr + 8,
2703 				       in6_dev->token.s6_addr + 8, 8);
2704 				read_unlock_bh(&in6_dev->lock);
2705 				tokenized = true;
2706 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2707 				   !ipv6_generate_stable_address(&addr, 0,
2708 								 in6_dev)) {
2709 				addr_flags |= IFA_F_STABLE_PRIVACY;
2710 				goto ok;
2711 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2712 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2713 				goto put;
2714 			} else {
2715 				dev_addr_generated = true;
2716 			}
2717 			goto ok;
2718 		}
2719 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2720 				    pinfo->prefix_len);
2721 		goto put;
2722 
2723 ok:
2724 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2725 						   &addr, addr_type,
2726 						   addr_flags, sllao,
2727 						   tokenized, valid_lft,
2728 						   prefered_lft);
2729 		if (err)
2730 			goto put;
2731 
2732 		/* Ignore error case here because previous prefix add addr was
2733 		 * successful which will be notified.
2734 		 */
2735 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2736 					      addr_type, addr_flags, sllao,
2737 					      tokenized, valid_lft,
2738 					      prefered_lft,
2739 					      dev_addr_generated);
2740 	}
2741 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2742 put:
2743 	in6_dev_put(in6_dev);
2744 }
2745 
2746 /*
2747  *	Set destination address.
2748  *	Special case for SIT interfaces where we create a new "virtual"
2749  *	device.
2750  */
2751 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2752 {
2753 	struct in6_ifreq ireq;
2754 	struct net_device *dev;
2755 	int err = -EINVAL;
2756 
2757 	rtnl_lock();
2758 
2759 	err = -EFAULT;
2760 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2761 		goto err_exit;
2762 
2763 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2764 
2765 	err = -ENODEV;
2766 	if (!dev)
2767 		goto err_exit;
2768 
2769 #if IS_ENABLED(CONFIG_IPV6_SIT)
2770 	if (dev->type == ARPHRD_SIT) {
2771 		const struct net_device_ops *ops = dev->netdev_ops;
2772 		struct ifreq ifr;
2773 		struct ip_tunnel_parm p;
2774 
2775 		err = -EADDRNOTAVAIL;
2776 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2777 			goto err_exit;
2778 
2779 		memset(&p, 0, sizeof(p));
2780 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2781 		p.iph.saddr = 0;
2782 		p.iph.version = 4;
2783 		p.iph.ihl = 5;
2784 		p.iph.protocol = IPPROTO_IPV6;
2785 		p.iph.ttl = 64;
2786 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2787 
2788 		if (ops->ndo_do_ioctl) {
2789 			mm_segment_t oldfs = get_fs();
2790 
2791 			set_fs(KERNEL_DS);
2792 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2793 			set_fs(oldfs);
2794 		} else
2795 			err = -EOPNOTSUPP;
2796 
2797 		if (err == 0) {
2798 			err = -ENOBUFS;
2799 			dev = __dev_get_by_name(net, p.name);
2800 			if (!dev)
2801 				goto err_exit;
2802 			err = dev_open(dev);
2803 		}
2804 	}
2805 #endif
2806 
2807 err_exit:
2808 	rtnl_unlock();
2809 	return err;
2810 }
2811 
2812 static int ipv6_mc_config(struct sock *sk, bool join,
2813 			  const struct in6_addr *addr, int ifindex)
2814 {
2815 	int ret;
2816 
2817 	ASSERT_RTNL();
2818 
2819 	lock_sock(sk);
2820 	if (join)
2821 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2822 	else
2823 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2824 	release_sock(sk);
2825 
2826 	return ret;
2827 }
2828 
2829 /*
2830  *	Manual configuration of address on an interface
2831  */
2832 static int inet6_addr_add(struct net *net, int ifindex,
2833 			  const struct in6_addr *pfx,
2834 			  const struct in6_addr *peer_pfx,
2835 			  unsigned int plen, __u32 ifa_flags,
2836 			  __u32 prefered_lft, __u32 valid_lft,
2837 			  struct netlink_ext_ack *extack)
2838 {
2839 	struct inet6_ifaddr *ifp;
2840 	struct inet6_dev *idev;
2841 	struct net_device *dev;
2842 	unsigned long timeout;
2843 	clock_t expires;
2844 	int scope;
2845 	u32 flags;
2846 
2847 	ASSERT_RTNL();
2848 
2849 	if (plen > 128)
2850 		return -EINVAL;
2851 
2852 	/* check the lifetime */
2853 	if (!valid_lft || prefered_lft > valid_lft)
2854 		return -EINVAL;
2855 
2856 	if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
2857 		return -EINVAL;
2858 
2859 	dev = __dev_get_by_index(net, ifindex);
2860 	if (!dev)
2861 		return -ENODEV;
2862 
2863 	idev = addrconf_add_dev(dev);
2864 	if (IS_ERR(idev))
2865 		return PTR_ERR(idev);
2866 
2867 	if (ifa_flags & IFA_F_MCAUTOJOIN) {
2868 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2869 					 true, pfx, ifindex);
2870 
2871 		if (ret < 0)
2872 			return ret;
2873 	}
2874 
2875 	scope = ipv6_addr_scope(pfx);
2876 
2877 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2878 	if (addrconf_finite_timeout(timeout)) {
2879 		expires = jiffies_to_clock_t(timeout * HZ);
2880 		valid_lft = timeout;
2881 		flags = RTF_EXPIRES;
2882 	} else {
2883 		expires = 0;
2884 		flags = 0;
2885 		ifa_flags |= IFA_F_PERMANENT;
2886 	}
2887 
2888 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2889 	if (addrconf_finite_timeout(timeout)) {
2890 		if (timeout == 0)
2891 			ifa_flags |= IFA_F_DEPRECATED;
2892 		prefered_lft = timeout;
2893 	}
2894 
2895 	ifp = ipv6_add_addr(idev, pfx, peer_pfx, plen, scope, ifa_flags,
2896 			    valid_lft, prefered_lft, true, extack);
2897 
2898 	if (!IS_ERR(ifp)) {
2899 		if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
2900 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2901 					      expires, flags, GFP_KERNEL);
2902 		}
2903 
2904 		/* Send a netlink notification if DAD is enabled and
2905 		 * optimistic flag is not set
2906 		 */
2907 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2908 			ipv6_ifa_notify(0, ifp);
2909 		/*
2910 		 * Note that section 3.1 of RFC 4429 indicates
2911 		 * that the Optimistic flag should not be set for
2912 		 * manually configured addresses
2913 		 */
2914 		addrconf_dad_start(ifp);
2915 		if (ifa_flags & IFA_F_MANAGETEMPADDR)
2916 			manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
2917 					 true, jiffies);
2918 		in6_ifa_put(ifp);
2919 		addrconf_verify_rtnl();
2920 		return 0;
2921 	} else if (ifa_flags & IFA_F_MCAUTOJOIN) {
2922 		ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2923 			       false, pfx, ifindex);
2924 	}
2925 
2926 	return PTR_ERR(ifp);
2927 }
2928 
2929 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2930 			  const struct in6_addr *pfx, unsigned int plen)
2931 {
2932 	struct inet6_ifaddr *ifp;
2933 	struct inet6_dev *idev;
2934 	struct net_device *dev;
2935 
2936 	if (plen > 128)
2937 		return -EINVAL;
2938 
2939 	dev = __dev_get_by_index(net, ifindex);
2940 	if (!dev)
2941 		return -ENODEV;
2942 
2943 	idev = __in6_dev_get(dev);
2944 	if (!idev)
2945 		return -ENXIO;
2946 
2947 	read_lock_bh(&idev->lock);
2948 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2949 		if (ifp->prefix_len == plen &&
2950 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2951 			in6_ifa_hold(ifp);
2952 			read_unlock_bh(&idev->lock);
2953 
2954 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2955 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2956 				manage_tempaddrs(idev, ifp, 0, 0, false,
2957 						 jiffies);
2958 			ipv6_del_addr(ifp);
2959 			addrconf_verify_rtnl();
2960 			if (ipv6_addr_is_multicast(pfx)) {
2961 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2962 					       false, pfx, dev->ifindex);
2963 			}
2964 			return 0;
2965 		}
2966 	}
2967 	read_unlock_bh(&idev->lock);
2968 	return -EADDRNOTAVAIL;
2969 }
2970 
2971 
2972 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2973 {
2974 	struct in6_ifreq ireq;
2975 	int err;
2976 
2977 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2978 		return -EPERM;
2979 
2980 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2981 		return -EFAULT;
2982 
2983 	rtnl_lock();
2984 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,
2985 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2986 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, NULL);
2987 	rtnl_unlock();
2988 	return err;
2989 }
2990 
2991 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2992 {
2993 	struct in6_ifreq ireq;
2994 	int err;
2995 
2996 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2997 		return -EPERM;
2998 
2999 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3000 		return -EFAULT;
3001 
3002 	rtnl_lock();
3003 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3004 			     ireq.ifr6_prefixlen);
3005 	rtnl_unlock();
3006 	return err;
3007 }
3008 
3009 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3010 		     int plen, int scope)
3011 {
3012 	struct inet6_ifaddr *ifp;
3013 
3014 	ifp = ipv6_add_addr(idev, addr, NULL, plen,
3015 			    scope, IFA_F_PERMANENT,
3016 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME,
3017 			    true, NULL);
3018 	if (!IS_ERR(ifp)) {
3019 		spin_lock_bh(&ifp->lock);
3020 		ifp->flags &= ~IFA_F_TENTATIVE;
3021 		spin_unlock_bh(&ifp->lock);
3022 		rt_genid_bump_ipv6(dev_net(idev->dev));
3023 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3024 		in6_ifa_put(ifp);
3025 	}
3026 }
3027 
3028 #if IS_ENABLED(CONFIG_IPV6_SIT)
3029 static void sit_add_v4_addrs(struct inet6_dev *idev)
3030 {
3031 	struct in6_addr addr;
3032 	struct net_device *dev;
3033 	struct net *net = dev_net(idev->dev);
3034 	int scope, plen;
3035 	u32 pflags = 0;
3036 
3037 	ASSERT_RTNL();
3038 
3039 	memset(&addr, 0, sizeof(struct in6_addr));
3040 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3041 
3042 	if (idev->dev->flags&IFF_POINTOPOINT) {
3043 		addr.s6_addr32[0] = htonl(0xfe800000);
3044 		scope = IFA_LINK;
3045 		plen = 64;
3046 	} else {
3047 		scope = IPV6_ADDR_COMPATv4;
3048 		plen = 96;
3049 		pflags |= RTF_NONEXTHOP;
3050 	}
3051 
3052 	if (addr.s6_addr32[3]) {
3053 		add_addr(idev, &addr, plen, scope);
3054 		addrconf_prefix_route(&addr, plen, idev->dev, 0, pflags,
3055 				      GFP_ATOMIC);
3056 		return;
3057 	}
3058 
3059 	for_each_netdev(net, dev) {
3060 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3061 		if (in_dev && (dev->flags & IFF_UP)) {
3062 			struct in_ifaddr *ifa;
3063 
3064 			int flag = scope;
3065 
3066 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3067 
3068 				addr.s6_addr32[3] = ifa->ifa_local;
3069 
3070 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3071 					continue;
3072 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3073 					if (idev->dev->flags&IFF_POINTOPOINT)
3074 						continue;
3075 					flag |= IFA_HOST;
3076 				}
3077 
3078 				add_addr(idev, &addr, plen, flag);
3079 				addrconf_prefix_route(&addr, plen, idev->dev, 0,
3080 						      pflags, GFP_ATOMIC);
3081 			}
3082 		}
3083 	}
3084 }
3085 #endif
3086 
3087 static void init_loopback(struct net_device *dev)
3088 {
3089 	struct inet6_dev  *idev;
3090 
3091 	/* ::1 */
3092 
3093 	ASSERT_RTNL();
3094 
3095 	idev = ipv6_find_idev(dev);
3096 	if (!idev) {
3097 		pr_debug("%s: add_dev failed\n", __func__);
3098 		return;
3099 	}
3100 
3101 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3102 }
3103 
3104 void addrconf_add_linklocal(struct inet6_dev *idev,
3105 			    const struct in6_addr *addr, u32 flags)
3106 {
3107 	struct inet6_ifaddr *ifp;
3108 	u32 addr_flags = flags | IFA_F_PERMANENT;
3109 
3110 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3111 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3112 	     idev->cnf.optimistic_dad) &&
3113 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3114 		addr_flags |= IFA_F_OPTIMISTIC;
3115 #endif
3116 
3117 	ifp = ipv6_add_addr(idev, addr, NULL, 64, IFA_LINK, addr_flags,
3118 			    INFINITY_LIFE_TIME, INFINITY_LIFE_TIME, true, NULL);
3119 	if (!IS_ERR(ifp)) {
3120 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev,
3121 				      0, 0, GFP_ATOMIC);
3122 		addrconf_dad_start(ifp);
3123 		in6_ifa_put(ifp);
3124 	}
3125 }
3126 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3127 
3128 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3129 {
3130 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3131 		return true;
3132 
3133 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3134 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3135 		return true;
3136 
3137 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3138 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3139 		return true;
3140 
3141 	return false;
3142 }
3143 
3144 static int ipv6_generate_stable_address(struct in6_addr *address,
3145 					u8 dad_count,
3146 					const struct inet6_dev *idev)
3147 {
3148 	static DEFINE_SPINLOCK(lock);
3149 	static __u32 digest[SHA_DIGEST_WORDS];
3150 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3151 
3152 	static union {
3153 		char __data[SHA_MESSAGE_BYTES];
3154 		struct {
3155 			struct in6_addr secret;
3156 			__be32 prefix[2];
3157 			unsigned char hwaddr[MAX_ADDR_LEN];
3158 			u8 dad_count;
3159 		} __packed;
3160 	} data;
3161 
3162 	struct in6_addr secret;
3163 	struct in6_addr temp;
3164 	struct net *net = dev_net(idev->dev);
3165 
3166 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3167 
3168 	if (idev->cnf.stable_secret.initialized)
3169 		secret = idev->cnf.stable_secret.secret;
3170 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3171 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3172 	else
3173 		return -1;
3174 
3175 retry:
3176 	spin_lock_bh(&lock);
3177 
3178 	sha_init(digest);
3179 	memset(&data, 0, sizeof(data));
3180 	memset(workspace, 0, sizeof(workspace));
3181 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3182 	data.prefix[0] = address->s6_addr32[0];
3183 	data.prefix[1] = address->s6_addr32[1];
3184 	data.secret = secret;
3185 	data.dad_count = dad_count;
3186 
3187 	sha_transform(digest, data.__data, workspace);
3188 
3189 	temp = *address;
3190 	temp.s6_addr32[2] = (__force __be32)digest[0];
3191 	temp.s6_addr32[3] = (__force __be32)digest[1];
3192 
3193 	spin_unlock_bh(&lock);
3194 
3195 	if (ipv6_reserved_interfaceid(temp)) {
3196 		dad_count++;
3197 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3198 			return -1;
3199 		goto retry;
3200 	}
3201 
3202 	*address = temp;
3203 	return 0;
3204 }
3205 
3206 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3207 {
3208 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3209 
3210 	if (s->initialized)
3211 		return;
3212 	s = &idev->cnf.stable_secret;
3213 	get_random_bytes(&s->secret, sizeof(s->secret));
3214 	s->initialized = true;
3215 }
3216 
3217 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3218 {
3219 	struct in6_addr addr;
3220 
3221 	/* no link local addresses on L3 master devices */
3222 	if (netif_is_l3_master(idev->dev))
3223 		return;
3224 
3225 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3226 
3227 	switch (idev->cnf.addr_gen_mode) {
3228 	case IN6_ADDR_GEN_MODE_RANDOM:
3229 		ipv6_gen_mode_random_init(idev);
3230 		/* fallthrough */
3231 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3232 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3233 			addrconf_add_linklocal(idev, &addr,
3234 					       IFA_F_STABLE_PRIVACY);
3235 		else if (prefix_route)
3236 			addrconf_prefix_route(&addr, 64, idev->dev,
3237 					      0, 0, GFP_KERNEL);
3238 		break;
3239 	case IN6_ADDR_GEN_MODE_EUI64:
3240 		/* addrconf_add_linklocal also adds a prefix_route and we
3241 		 * only need to care about prefix routes if ipv6_generate_eui64
3242 		 * couldn't generate one.
3243 		 */
3244 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3245 			addrconf_add_linklocal(idev, &addr, 0);
3246 		else if (prefix_route)
3247 			addrconf_prefix_route(&addr, 64, idev->dev,
3248 					      0, 0, GFP_KERNEL);
3249 		break;
3250 	case IN6_ADDR_GEN_MODE_NONE:
3251 	default:
3252 		/* will not add any link local address */
3253 		break;
3254 	}
3255 }
3256 
3257 static void addrconf_dev_config(struct net_device *dev)
3258 {
3259 	struct inet6_dev *idev;
3260 
3261 	ASSERT_RTNL();
3262 
3263 	if ((dev->type != ARPHRD_ETHER) &&
3264 	    (dev->type != ARPHRD_FDDI) &&
3265 	    (dev->type != ARPHRD_ARCNET) &&
3266 	    (dev->type != ARPHRD_INFINIBAND) &&
3267 	    (dev->type != ARPHRD_IEEE1394) &&
3268 	    (dev->type != ARPHRD_TUNNEL6) &&
3269 	    (dev->type != ARPHRD_6LOWPAN) &&
3270 	    (dev->type != ARPHRD_IP6GRE) &&
3271 	    (dev->type != ARPHRD_IPGRE) &&
3272 	    (dev->type != ARPHRD_TUNNEL) &&
3273 	    (dev->type != ARPHRD_NONE)) {
3274 		/* Alas, we support only Ethernet autoconfiguration. */
3275 		return;
3276 	}
3277 
3278 	idev = addrconf_add_dev(dev);
3279 	if (IS_ERR(idev))
3280 		return;
3281 
3282 	/* this device type has no EUI support */
3283 	if (dev->type == ARPHRD_NONE &&
3284 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3285 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3286 
3287 	addrconf_addr_gen(idev, false);
3288 }
3289 
3290 #if IS_ENABLED(CONFIG_IPV6_SIT)
3291 static void addrconf_sit_config(struct net_device *dev)
3292 {
3293 	struct inet6_dev *idev;
3294 
3295 	ASSERT_RTNL();
3296 
3297 	/*
3298 	 * Configure the tunnel with one of our IPv4
3299 	 * addresses... we should configure all of
3300 	 * our v4 addrs in the tunnel
3301 	 */
3302 
3303 	idev = ipv6_find_idev(dev);
3304 	if (!idev) {
3305 		pr_debug("%s: add_dev failed\n", __func__);
3306 		return;
3307 	}
3308 
3309 	if (dev->priv_flags & IFF_ISATAP) {
3310 		addrconf_addr_gen(idev, false);
3311 		return;
3312 	}
3313 
3314 	sit_add_v4_addrs(idev);
3315 
3316 	if (dev->flags&IFF_POINTOPOINT)
3317 		addrconf_add_mroute(dev);
3318 }
3319 #endif
3320 
3321 #if IS_ENABLED(CONFIG_NET_IPGRE)
3322 static void addrconf_gre_config(struct net_device *dev)
3323 {
3324 	struct inet6_dev *idev;
3325 
3326 	ASSERT_RTNL();
3327 
3328 	idev = ipv6_find_idev(dev);
3329 	if (!idev) {
3330 		pr_debug("%s: add_dev failed\n", __func__);
3331 		return;
3332 	}
3333 
3334 	addrconf_addr_gen(idev, true);
3335 	if (dev->flags & IFF_POINTOPOINT)
3336 		addrconf_add_mroute(dev);
3337 }
3338 #endif
3339 
3340 static int fixup_permanent_addr(struct net *net,
3341 				struct inet6_dev *idev,
3342 				struct inet6_ifaddr *ifp)
3343 {
3344 	/* !fib6_node means the host route was removed from the
3345 	 * FIB, for example, if 'lo' device is taken down. In that
3346 	 * case regenerate the host route.
3347 	 */
3348 	if (!ifp->rt || !ifp->rt->fib6_node) {
3349 		struct fib6_info *f6i, *prev;
3350 
3351 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3352 					 GFP_ATOMIC);
3353 		if (IS_ERR(f6i))
3354 			return PTR_ERR(f6i);
3355 
3356 		/* ifp->rt can be accessed outside of rtnl */
3357 		spin_lock(&ifp->lock);
3358 		prev = ifp->rt;
3359 		ifp->rt = f6i;
3360 		spin_unlock(&ifp->lock);
3361 
3362 		fib6_info_release(prev);
3363 	}
3364 
3365 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3366 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3367 				      idev->dev, 0, 0, GFP_ATOMIC);
3368 	}
3369 
3370 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3371 		addrconf_dad_start(ifp);
3372 
3373 	return 0;
3374 }
3375 
3376 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3377 {
3378 	struct inet6_ifaddr *ifp, *tmp;
3379 	struct inet6_dev *idev;
3380 
3381 	idev = __in6_dev_get(dev);
3382 	if (!idev)
3383 		return;
3384 
3385 	write_lock_bh(&idev->lock);
3386 
3387 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3388 		if ((ifp->flags & IFA_F_PERMANENT) &&
3389 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3390 			write_unlock_bh(&idev->lock);
3391 			in6_ifa_hold(ifp);
3392 			ipv6_del_addr(ifp);
3393 			write_lock_bh(&idev->lock);
3394 
3395 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3396 					     idev->dev->name, &ifp->addr);
3397 		}
3398 	}
3399 
3400 	write_unlock_bh(&idev->lock);
3401 }
3402 
3403 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3404 			   void *ptr)
3405 {
3406 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3407 	struct netdev_notifier_changeupper_info *info;
3408 	struct inet6_dev *idev = __in6_dev_get(dev);
3409 	struct net *net = dev_net(dev);
3410 	int run_pending = 0;
3411 	int err;
3412 
3413 	switch (event) {
3414 	case NETDEV_REGISTER:
3415 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3416 			idev = ipv6_add_dev(dev);
3417 			if (IS_ERR(idev))
3418 				return notifier_from_errno(PTR_ERR(idev));
3419 		}
3420 		break;
3421 
3422 	case NETDEV_CHANGEMTU:
3423 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3424 		if (dev->mtu < IPV6_MIN_MTU) {
3425 			addrconf_ifdown(dev, dev != net->loopback_dev);
3426 			break;
3427 		}
3428 
3429 		if (idev) {
3430 			rt6_mtu_change(dev, dev->mtu);
3431 			idev->cnf.mtu6 = dev->mtu;
3432 			break;
3433 		}
3434 
3435 		/* allocate new idev */
3436 		idev = ipv6_add_dev(dev);
3437 		if (IS_ERR(idev))
3438 			break;
3439 
3440 		/* device is still not ready */
3441 		if (!(idev->if_flags & IF_READY))
3442 			break;
3443 
3444 		run_pending = 1;
3445 
3446 		/* fall through */
3447 
3448 	case NETDEV_UP:
3449 	case NETDEV_CHANGE:
3450 		if (dev->flags & IFF_SLAVE)
3451 			break;
3452 
3453 		if (idev && idev->cnf.disable_ipv6)
3454 			break;
3455 
3456 		if (event == NETDEV_UP) {
3457 			/* restore routes for permanent addresses */
3458 			addrconf_permanent_addr(net, dev);
3459 
3460 			if (!addrconf_link_ready(dev)) {
3461 				/* device is not ready yet. */
3462 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3463 					dev->name);
3464 				break;
3465 			}
3466 
3467 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3468 				idev = ipv6_add_dev(dev);
3469 
3470 			if (!IS_ERR_OR_NULL(idev)) {
3471 				idev->if_flags |= IF_READY;
3472 				run_pending = 1;
3473 			}
3474 		} else if (event == NETDEV_CHANGE) {
3475 			if (!addrconf_link_ready(dev)) {
3476 				/* device is still not ready. */
3477 				rt6_sync_down_dev(dev, event);
3478 				break;
3479 			}
3480 
3481 			if (idev) {
3482 				if (idev->if_flags & IF_READY) {
3483 					/* device is already configured -
3484 					 * but resend MLD reports, we might
3485 					 * have roamed and need to update
3486 					 * multicast snooping switches
3487 					 */
3488 					ipv6_mc_up(idev);
3489 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3490 					break;
3491 				}
3492 				idev->if_flags |= IF_READY;
3493 			}
3494 
3495 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3496 				dev->name);
3497 
3498 			run_pending = 1;
3499 		}
3500 
3501 		switch (dev->type) {
3502 #if IS_ENABLED(CONFIG_IPV6_SIT)
3503 		case ARPHRD_SIT:
3504 			addrconf_sit_config(dev);
3505 			break;
3506 #endif
3507 #if IS_ENABLED(CONFIG_NET_IPGRE)
3508 		case ARPHRD_IPGRE:
3509 			addrconf_gre_config(dev);
3510 			break;
3511 #endif
3512 		case ARPHRD_LOOPBACK:
3513 			init_loopback(dev);
3514 			break;
3515 
3516 		default:
3517 			addrconf_dev_config(dev);
3518 			break;
3519 		}
3520 
3521 		if (!IS_ERR_OR_NULL(idev)) {
3522 			if (run_pending)
3523 				addrconf_dad_run(idev);
3524 
3525 			/* Device has an address by now */
3526 			rt6_sync_up(dev, RTNH_F_DEAD);
3527 
3528 			/*
3529 			 * If the MTU changed during the interface down,
3530 			 * when the interface up, the changed MTU must be
3531 			 * reflected in the idev as well as routers.
3532 			 */
3533 			if (idev->cnf.mtu6 != dev->mtu &&
3534 			    dev->mtu >= IPV6_MIN_MTU) {
3535 				rt6_mtu_change(dev, dev->mtu);
3536 				idev->cnf.mtu6 = dev->mtu;
3537 			}
3538 			idev->tstamp = jiffies;
3539 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3540 
3541 			/*
3542 			 * If the changed mtu during down is lower than
3543 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3544 			 */
3545 			if (dev->mtu < IPV6_MIN_MTU)
3546 				addrconf_ifdown(dev, dev != net->loopback_dev);
3547 		}
3548 		break;
3549 
3550 	case NETDEV_DOWN:
3551 	case NETDEV_UNREGISTER:
3552 		/*
3553 		 *	Remove all addresses from this interface.
3554 		 */
3555 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3556 		break;
3557 
3558 	case NETDEV_CHANGENAME:
3559 		if (idev) {
3560 			snmp6_unregister_dev(idev);
3561 			addrconf_sysctl_unregister(idev);
3562 			err = addrconf_sysctl_register(idev);
3563 			if (err)
3564 				return notifier_from_errno(err);
3565 			err = snmp6_register_dev(idev);
3566 			if (err) {
3567 				addrconf_sysctl_unregister(idev);
3568 				return notifier_from_errno(err);
3569 			}
3570 		}
3571 		break;
3572 
3573 	case NETDEV_PRE_TYPE_CHANGE:
3574 	case NETDEV_POST_TYPE_CHANGE:
3575 		if (idev)
3576 			addrconf_type_change(dev, event);
3577 		break;
3578 
3579 	case NETDEV_CHANGEUPPER:
3580 		info = ptr;
3581 
3582 		/* flush all routes if dev is linked to or unlinked from
3583 		 * an L3 master device (e.g., VRF)
3584 		 */
3585 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3586 			addrconf_ifdown(dev, 0);
3587 	}
3588 
3589 	return NOTIFY_OK;
3590 }
3591 
3592 /*
3593  *	addrconf module should be notified of a device going up
3594  */
3595 static struct notifier_block ipv6_dev_notf = {
3596 	.notifier_call = addrconf_notify,
3597 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3598 };
3599 
3600 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3601 {
3602 	struct inet6_dev *idev;
3603 	ASSERT_RTNL();
3604 
3605 	idev = __in6_dev_get(dev);
3606 
3607 	if (event == NETDEV_POST_TYPE_CHANGE)
3608 		ipv6_mc_remap(idev);
3609 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3610 		ipv6_mc_unmap(idev);
3611 }
3612 
3613 static bool addr_is_local(const struct in6_addr *addr)
3614 {
3615 	return ipv6_addr_type(addr) &
3616 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3617 }
3618 
3619 static int addrconf_ifdown(struct net_device *dev, int how)
3620 {
3621 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3622 	struct net *net = dev_net(dev);
3623 	struct inet6_dev *idev;
3624 	struct inet6_ifaddr *ifa, *tmp;
3625 	bool keep_addr = false;
3626 	int state, i;
3627 
3628 	ASSERT_RTNL();
3629 
3630 	rt6_disable_ip(dev, event);
3631 
3632 	idev = __in6_dev_get(dev);
3633 	if (!idev)
3634 		return -ENODEV;
3635 
3636 	/*
3637 	 * Step 1: remove reference to ipv6 device from parent device.
3638 	 *	   Do not dev_put!
3639 	 */
3640 	if (how) {
3641 		idev->dead = 1;
3642 
3643 		/* protected by rtnl_lock */
3644 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3645 
3646 		/* Step 1.5: remove snmp6 entry */
3647 		snmp6_unregister_dev(idev);
3648 
3649 	}
3650 
3651 	/* combine the user config with event to determine if permanent
3652 	 * addresses are to be removed from address hash table
3653 	 */
3654 	if (!how && !idev->cnf.disable_ipv6) {
3655 		/* aggregate the system setting and interface setting */
3656 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3657 
3658 		if (!_keep_addr)
3659 			_keep_addr = idev->cnf.keep_addr_on_down;
3660 
3661 		keep_addr = (_keep_addr > 0);
3662 	}
3663 
3664 	/* Step 2: clear hash table */
3665 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3666 		struct hlist_head *h = &inet6_addr_lst[i];
3667 
3668 		spin_lock_bh(&addrconf_hash_lock);
3669 restart:
3670 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3671 			if (ifa->idev == idev) {
3672 				addrconf_del_dad_work(ifa);
3673 				/* combined flag + permanent flag decide if
3674 				 * address is retained on a down event
3675 				 */
3676 				if (!keep_addr ||
3677 				    !(ifa->flags & IFA_F_PERMANENT) ||
3678 				    addr_is_local(&ifa->addr)) {
3679 					hlist_del_init_rcu(&ifa->addr_lst);
3680 					goto restart;
3681 				}
3682 			}
3683 		}
3684 		spin_unlock_bh(&addrconf_hash_lock);
3685 	}
3686 
3687 	write_lock_bh(&idev->lock);
3688 
3689 	addrconf_del_rs_timer(idev);
3690 
3691 	/* Step 2: clear flags for stateless addrconf */
3692 	if (!how)
3693 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3694 
3695 	/* Step 3: clear tempaddr list */
3696 	while (!list_empty(&idev->tempaddr_list)) {
3697 		ifa = list_first_entry(&idev->tempaddr_list,
3698 				       struct inet6_ifaddr, tmp_list);
3699 		list_del(&ifa->tmp_list);
3700 		write_unlock_bh(&idev->lock);
3701 		spin_lock_bh(&ifa->lock);
3702 
3703 		if (ifa->ifpub) {
3704 			in6_ifa_put(ifa->ifpub);
3705 			ifa->ifpub = NULL;
3706 		}
3707 		spin_unlock_bh(&ifa->lock);
3708 		in6_ifa_put(ifa);
3709 		write_lock_bh(&idev->lock);
3710 	}
3711 
3712 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3713 		struct fib6_info *rt = NULL;
3714 		bool keep;
3715 
3716 		addrconf_del_dad_work(ifa);
3717 
3718 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3719 			!addr_is_local(&ifa->addr);
3720 
3721 		write_unlock_bh(&idev->lock);
3722 		spin_lock_bh(&ifa->lock);
3723 
3724 		if (keep) {
3725 			/* set state to skip the notifier below */
3726 			state = INET6_IFADDR_STATE_DEAD;
3727 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3728 			if (!(ifa->flags & IFA_F_NODAD))
3729 				ifa->flags |= IFA_F_TENTATIVE;
3730 
3731 			rt = ifa->rt;
3732 			ifa->rt = NULL;
3733 		} else {
3734 			state = ifa->state;
3735 			ifa->state = INET6_IFADDR_STATE_DEAD;
3736 		}
3737 
3738 		spin_unlock_bh(&ifa->lock);
3739 
3740 		if (rt)
3741 			ip6_del_rt(net, rt);
3742 
3743 		if (state != INET6_IFADDR_STATE_DEAD) {
3744 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3745 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3746 		} else {
3747 			if (idev->cnf.forwarding)
3748 				addrconf_leave_anycast(ifa);
3749 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3750 		}
3751 
3752 		write_lock_bh(&idev->lock);
3753 		if (!keep) {
3754 			list_del_rcu(&ifa->if_list);
3755 			in6_ifa_put(ifa);
3756 		}
3757 	}
3758 
3759 	write_unlock_bh(&idev->lock);
3760 
3761 	/* Step 5: Discard anycast and multicast list */
3762 	if (how) {
3763 		ipv6_ac_destroy_dev(idev);
3764 		ipv6_mc_destroy_dev(idev);
3765 	} else {
3766 		ipv6_mc_down(idev);
3767 	}
3768 
3769 	idev->tstamp = jiffies;
3770 
3771 	/* Last: Shot the device (if unregistered) */
3772 	if (how) {
3773 		addrconf_sysctl_unregister(idev);
3774 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3775 		neigh_ifdown(&nd_tbl, dev);
3776 		in6_dev_put(idev);
3777 	}
3778 	return 0;
3779 }
3780 
3781 static void addrconf_rs_timer(struct timer_list *t)
3782 {
3783 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3784 	struct net_device *dev = idev->dev;
3785 	struct in6_addr lladdr;
3786 
3787 	write_lock(&idev->lock);
3788 	if (idev->dead || !(idev->if_flags & IF_READY))
3789 		goto out;
3790 
3791 	if (!ipv6_accept_ra(idev))
3792 		goto out;
3793 
3794 	/* Announcement received after solicitation was sent */
3795 	if (idev->if_flags & IF_RA_RCVD)
3796 		goto out;
3797 
3798 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3799 		write_unlock(&idev->lock);
3800 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3801 			ndisc_send_rs(dev, &lladdr,
3802 				      &in6addr_linklocal_allrouters);
3803 		else
3804 			goto put;
3805 
3806 		write_lock(&idev->lock);
3807 		idev->rs_interval = rfc3315_s14_backoff_update(
3808 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3809 		/* The wait after the last probe can be shorter */
3810 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3811 					     idev->cnf.rtr_solicits) ?
3812 				      idev->cnf.rtr_solicit_delay :
3813 				      idev->rs_interval);
3814 	} else {
3815 		/*
3816 		 * Note: we do not support deprecated "all on-link"
3817 		 * assumption any longer.
3818 		 */
3819 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3820 	}
3821 
3822 out:
3823 	write_unlock(&idev->lock);
3824 put:
3825 	in6_dev_put(idev);
3826 }
3827 
3828 /*
3829  *	Duplicate Address Detection
3830  */
3831 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3832 {
3833 	unsigned long rand_num;
3834 	struct inet6_dev *idev = ifp->idev;
3835 	u64 nonce;
3836 
3837 	if (ifp->flags & IFA_F_OPTIMISTIC)
3838 		rand_num = 0;
3839 	else
3840 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3841 
3842 	nonce = 0;
3843 	if (idev->cnf.enhanced_dad ||
3844 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3845 		do
3846 			get_random_bytes(&nonce, 6);
3847 		while (nonce == 0);
3848 	}
3849 	ifp->dad_nonce = nonce;
3850 	ifp->dad_probes = idev->cnf.dad_transmits;
3851 	addrconf_mod_dad_work(ifp, rand_num);
3852 }
3853 
3854 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3855 {
3856 	struct inet6_dev *idev = ifp->idev;
3857 	struct net_device *dev = idev->dev;
3858 	bool bump_id, notify = false;
3859 	struct net *net;
3860 
3861 	addrconf_join_solict(dev, &ifp->addr);
3862 
3863 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3864 
3865 	read_lock_bh(&idev->lock);
3866 	spin_lock(&ifp->lock);
3867 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3868 		goto out;
3869 
3870 	net = dev_net(dev);
3871 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3872 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3873 	     idev->cnf.accept_dad < 1) ||
3874 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3875 	    ifp->flags & IFA_F_NODAD) {
3876 		bool send_na = false;
3877 
3878 		if (ifp->flags & IFA_F_TENTATIVE &&
3879 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3880 			send_na = true;
3881 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3882 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3883 		spin_unlock(&ifp->lock);
3884 		read_unlock_bh(&idev->lock);
3885 
3886 		addrconf_dad_completed(ifp, bump_id, send_na);
3887 		return;
3888 	}
3889 
3890 	if (!(idev->if_flags & IF_READY)) {
3891 		spin_unlock(&ifp->lock);
3892 		read_unlock_bh(&idev->lock);
3893 		/*
3894 		 * If the device is not ready:
3895 		 * - keep it tentative if it is a permanent address.
3896 		 * - otherwise, kill it.
3897 		 */
3898 		in6_ifa_hold(ifp);
3899 		addrconf_dad_stop(ifp, 0);
3900 		return;
3901 	}
3902 
3903 	/*
3904 	 * Optimistic nodes can start receiving
3905 	 * Frames right away
3906 	 */
3907 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3908 		ip6_ins_rt(net, ifp->rt);
3909 		if (ipv6_use_optimistic_addr(net, idev)) {
3910 			/* Because optimistic nodes can use this address,
3911 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3912 			 */
3913 			notify = true;
3914 		}
3915 	}
3916 
3917 	addrconf_dad_kick(ifp);
3918 out:
3919 	spin_unlock(&ifp->lock);
3920 	read_unlock_bh(&idev->lock);
3921 	if (notify)
3922 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3923 }
3924 
3925 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3926 {
3927 	bool begin_dad = false;
3928 
3929 	spin_lock_bh(&ifp->lock);
3930 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3931 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3932 		begin_dad = true;
3933 	}
3934 	spin_unlock_bh(&ifp->lock);
3935 
3936 	if (begin_dad)
3937 		addrconf_mod_dad_work(ifp, 0);
3938 }
3939 
3940 static void addrconf_dad_work(struct work_struct *w)
3941 {
3942 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3943 						struct inet6_ifaddr,
3944 						dad_work);
3945 	struct inet6_dev *idev = ifp->idev;
3946 	bool bump_id, disable_ipv6 = false;
3947 	struct in6_addr mcaddr;
3948 
3949 	enum {
3950 		DAD_PROCESS,
3951 		DAD_BEGIN,
3952 		DAD_ABORT,
3953 	} action = DAD_PROCESS;
3954 
3955 	rtnl_lock();
3956 
3957 	spin_lock_bh(&ifp->lock);
3958 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3959 		action = DAD_BEGIN;
3960 		ifp->state = INET6_IFADDR_STATE_DAD;
3961 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3962 		action = DAD_ABORT;
3963 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3964 
3965 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3966 		     idev->cnf.accept_dad > 1) &&
3967 		    !idev->cnf.disable_ipv6 &&
3968 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3969 			struct in6_addr addr;
3970 
3971 			addr.s6_addr32[0] = htonl(0xfe800000);
3972 			addr.s6_addr32[1] = 0;
3973 
3974 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3975 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3976 				/* DAD failed for link-local based on MAC */
3977 				idev->cnf.disable_ipv6 = 1;
3978 
3979 				pr_info("%s: IPv6 being disabled!\n",
3980 					ifp->idev->dev->name);
3981 				disable_ipv6 = true;
3982 			}
3983 		}
3984 	}
3985 	spin_unlock_bh(&ifp->lock);
3986 
3987 	if (action == DAD_BEGIN) {
3988 		addrconf_dad_begin(ifp);
3989 		goto out;
3990 	} else if (action == DAD_ABORT) {
3991 		in6_ifa_hold(ifp);
3992 		addrconf_dad_stop(ifp, 1);
3993 		if (disable_ipv6)
3994 			addrconf_ifdown(idev->dev, 0);
3995 		goto out;
3996 	}
3997 
3998 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
3999 		goto out;
4000 
4001 	write_lock_bh(&idev->lock);
4002 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4003 		write_unlock_bh(&idev->lock);
4004 		goto out;
4005 	}
4006 
4007 	spin_lock(&ifp->lock);
4008 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4009 		spin_unlock(&ifp->lock);
4010 		write_unlock_bh(&idev->lock);
4011 		goto out;
4012 	}
4013 
4014 	if (ifp->dad_probes == 0) {
4015 		bool send_na = false;
4016 
4017 		/*
4018 		 * DAD was successful
4019 		 */
4020 
4021 		if (ifp->flags & IFA_F_TENTATIVE &&
4022 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4023 			send_na = true;
4024 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4025 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4026 		spin_unlock(&ifp->lock);
4027 		write_unlock_bh(&idev->lock);
4028 
4029 		addrconf_dad_completed(ifp, bump_id, send_na);
4030 
4031 		goto out;
4032 	}
4033 
4034 	ifp->dad_probes--;
4035 	addrconf_mod_dad_work(ifp,
4036 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4037 	spin_unlock(&ifp->lock);
4038 	write_unlock_bh(&idev->lock);
4039 
4040 	/* send a neighbour solicitation for our addr */
4041 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4042 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4043 		      ifp->dad_nonce);
4044 out:
4045 	in6_ifa_put(ifp);
4046 	rtnl_unlock();
4047 }
4048 
4049 /* ifp->idev must be at least read locked */
4050 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4051 {
4052 	struct inet6_ifaddr *ifpiter;
4053 	struct inet6_dev *idev = ifp->idev;
4054 
4055 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4056 		if (ifpiter->scope > IFA_LINK)
4057 			break;
4058 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4059 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4060 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4061 		    IFA_F_PERMANENT)
4062 			return false;
4063 	}
4064 	return true;
4065 }
4066 
4067 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4068 				   bool send_na)
4069 {
4070 	struct net_device *dev = ifp->idev->dev;
4071 	struct in6_addr lladdr;
4072 	bool send_rs, send_mld;
4073 
4074 	addrconf_del_dad_work(ifp);
4075 
4076 	/*
4077 	 *	Configure the address for reception. Now it is valid.
4078 	 */
4079 
4080 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4081 
4082 	/* If added prefix is link local and we are prepared to process
4083 	   router advertisements, start sending router solicitations.
4084 	 */
4085 
4086 	read_lock_bh(&ifp->idev->lock);
4087 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4088 	send_rs = send_mld &&
4089 		  ipv6_accept_ra(ifp->idev) &&
4090 		  ifp->idev->cnf.rtr_solicits != 0 &&
4091 		  (dev->flags&IFF_LOOPBACK) == 0;
4092 	read_unlock_bh(&ifp->idev->lock);
4093 
4094 	/* While dad is in progress mld report's source address is in6_addrany.
4095 	 * Resend with proper ll now.
4096 	 */
4097 	if (send_mld)
4098 		ipv6_mc_dad_complete(ifp->idev);
4099 
4100 	/* send unsolicited NA if enabled */
4101 	if (send_na &&
4102 	    (ifp->idev->cnf.ndisc_notify ||
4103 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4104 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4105 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4106 			      /*solicited=*/ false, /*override=*/ true,
4107 			      /*inc_opt=*/ true);
4108 	}
4109 
4110 	if (send_rs) {
4111 		/*
4112 		 *	If a host as already performed a random delay
4113 		 *	[...] as part of DAD [...] there is no need
4114 		 *	to delay again before sending the first RS
4115 		 */
4116 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4117 			return;
4118 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4119 
4120 		write_lock_bh(&ifp->idev->lock);
4121 		spin_lock(&ifp->lock);
4122 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4123 			ifp->idev->cnf.rtr_solicit_interval);
4124 		ifp->idev->rs_probes = 1;
4125 		ifp->idev->if_flags |= IF_RS_SENT;
4126 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4127 		spin_unlock(&ifp->lock);
4128 		write_unlock_bh(&ifp->idev->lock);
4129 	}
4130 
4131 	if (bump_id)
4132 		rt_genid_bump_ipv6(dev_net(dev));
4133 
4134 	/* Make sure that a new temporary address will be created
4135 	 * before this temporary address becomes deprecated.
4136 	 */
4137 	if (ifp->flags & IFA_F_TEMPORARY)
4138 		addrconf_verify_rtnl();
4139 }
4140 
4141 static void addrconf_dad_run(struct inet6_dev *idev)
4142 {
4143 	struct inet6_ifaddr *ifp;
4144 
4145 	read_lock_bh(&idev->lock);
4146 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4147 		spin_lock(&ifp->lock);
4148 		if (ifp->flags & IFA_F_TENTATIVE &&
4149 		    ifp->state == INET6_IFADDR_STATE_DAD)
4150 			addrconf_dad_kick(ifp);
4151 		spin_unlock(&ifp->lock);
4152 	}
4153 	read_unlock_bh(&idev->lock);
4154 }
4155 
4156 #ifdef CONFIG_PROC_FS
4157 struct if6_iter_state {
4158 	struct seq_net_private p;
4159 	int bucket;
4160 	int offset;
4161 };
4162 
4163 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4164 {
4165 	struct if6_iter_state *state = seq->private;
4166 	struct net *net = seq_file_net(seq);
4167 	struct inet6_ifaddr *ifa = NULL;
4168 	int p = 0;
4169 
4170 	/* initial bucket if pos is 0 */
4171 	if (pos == 0) {
4172 		state->bucket = 0;
4173 		state->offset = 0;
4174 	}
4175 
4176 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4177 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4178 					 addr_lst) {
4179 			if (!net_eq(dev_net(ifa->idev->dev), net))
4180 				continue;
4181 			/* sync with offset */
4182 			if (p < state->offset) {
4183 				p++;
4184 				continue;
4185 			}
4186 			state->offset++;
4187 			return ifa;
4188 		}
4189 
4190 		/* prepare for next bucket */
4191 		state->offset = 0;
4192 		p = 0;
4193 	}
4194 	return NULL;
4195 }
4196 
4197 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4198 					 struct inet6_ifaddr *ifa)
4199 {
4200 	struct if6_iter_state *state = seq->private;
4201 	struct net *net = seq_file_net(seq);
4202 
4203 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4204 		if (!net_eq(dev_net(ifa->idev->dev), net))
4205 			continue;
4206 		state->offset++;
4207 		return ifa;
4208 	}
4209 
4210 	while (++state->bucket < IN6_ADDR_HSIZE) {
4211 		state->offset = 0;
4212 		hlist_for_each_entry_rcu(ifa,
4213 				     &inet6_addr_lst[state->bucket], addr_lst) {
4214 			if (!net_eq(dev_net(ifa->idev->dev), net))
4215 				continue;
4216 			state->offset++;
4217 			return ifa;
4218 		}
4219 	}
4220 
4221 	return NULL;
4222 }
4223 
4224 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4225 	__acquires(rcu)
4226 {
4227 	rcu_read_lock();
4228 	return if6_get_first(seq, *pos);
4229 }
4230 
4231 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4232 {
4233 	struct inet6_ifaddr *ifa;
4234 
4235 	ifa = if6_get_next(seq, v);
4236 	++*pos;
4237 	return ifa;
4238 }
4239 
4240 static void if6_seq_stop(struct seq_file *seq, void *v)
4241 	__releases(rcu)
4242 {
4243 	rcu_read_unlock();
4244 }
4245 
4246 static int if6_seq_show(struct seq_file *seq, void *v)
4247 {
4248 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4249 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4250 		   &ifp->addr,
4251 		   ifp->idev->dev->ifindex,
4252 		   ifp->prefix_len,
4253 		   ifp->scope,
4254 		   (u8) ifp->flags,
4255 		   ifp->idev->dev->name);
4256 	return 0;
4257 }
4258 
4259 static const struct seq_operations if6_seq_ops = {
4260 	.start	= if6_seq_start,
4261 	.next	= if6_seq_next,
4262 	.show	= if6_seq_show,
4263 	.stop	= if6_seq_stop,
4264 };
4265 
4266 static int if6_seq_open(struct inode *inode, struct file *file)
4267 {
4268 	return seq_open_net(inode, file, &if6_seq_ops,
4269 			    sizeof(struct if6_iter_state));
4270 }
4271 
4272 static const struct file_operations if6_fops = {
4273 	.open		= if6_seq_open,
4274 	.read		= seq_read,
4275 	.llseek		= seq_lseek,
4276 	.release	= seq_release_net,
4277 };
4278 
4279 static int __net_init if6_proc_net_init(struct net *net)
4280 {
4281 	if (!proc_create("if_inet6", 0444, net->proc_net, &if6_fops))
4282 		return -ENOMEM;
4283 	return 0;
4284 }
4285 
4286 static void __net_exit if6_proc_net_exit(struct net *net)
4287 {
4288 	remove_proc_entry("if_inet6", net->proc_net);
4289 }
4290 
4291 static struct pernet_operations if6_proc_net_ops = {
4292 	.init = if6_proc_net_init,
4293 	.exit = if6_proc_net_exit,
4294 };
4295 
4296 int __init if6_proc_init(void)
4297 {
4298 	return register_pernet_subsys(&if6_proc_net_ops);
4299 }
4300 
4301 void if6_proc_exit(void)
4302 {
4303 	unregister_pernet_subsys(&if6_proc_net_ops);
4304 }
4305 #endif	/* CONFIG_PROC_FS */
4306 
4307 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4308 /* Check if address is a home address configured on any interface. */
4309 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4310 {
4311 	unsigned int hash = inet6_addr_hash(net, addr);
4312 	struct inet6_ifaddr *ifp = NULL;
4313 	int ret = 0;
4314 
4315 	rcu_read_lock();
4316 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4317 		if (!net_eq(dev_net(ifp->idev->dev), net))
4318 			continue;
4319 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4320 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4321 			ret = 1;
4322 			break;
4323 		}
4324 	}
4325 	rcu_read_unlock();
4326 	return ret;
4327 }
4328 #endif
4329 
4330 /*
4331  *	Periodic address status verification
4332  */
4333 
4334 static void addrconf_verify_rtnl(void)
4335 {
4336 	unsigned long now, next, next_sec, next_sched;
4337 	struct inet6_ifaddr *ifp;
4338 	int i;
4339 
4340 	ASSERT_RTNL();
4341 
4342 	rcu_read_lock_bh();
4343 	now = jiffies;
4344 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4345 
4346 	cancel_delayed_work(&addr_chk_work);
4347 
4348 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4349 restart:
4350 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4351 			unsigned long age;
4352 
4353 			/* When setting preferred_lft to a value not zero or
4354 			 * infinity, while valid_lft is infinity
4355 			 * IFA_F_PERMANENT has a non-infinity life time.
4356 			 */
4357 			if ((ifp->flags & IFA_F_PERMANENT) &&
4358 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4359 				continue;
4360 
4361 			spin_lock(&ifp->lock);
4362 			/* We try to batch several events at once. */
4363 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4364 
4365 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4366 			    age >= ifp->valid_lft) {
4367 				spin_unlock(&ifp->lock);
4368 				in6_ifa_hold(ifp);
4369 				ipv6_del_addr(ifp);
4370 				goto restart;
4371 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4372 				spin_unlock(&ifp->lock);
4373 				continue;
4374 			} else if (age >= ifp->prefered_lft) {
4375 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4376 				int deprecate = 0;
4377 
4378 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4379 					deprecate = 1;
4380 					ifp->flags |= IFA_F_DEPRECATED;
4381 				}
4382 
4383 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4384 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4385 					next = ifp->tstamp + ifp->valid_lft * HZ;
4386 
4387 				spin_unlock(&ifp->lock);
4388 
4389 				if (deprecate) {
4390 					in6_ifa_hold(ifp);
4391 
4392 					ipv6_ifa_notify(0, ifp);
4393 					in6_ifa_put(ifp);
4394 					goto restart;
4395 				}
4396 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4397 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4398 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4399 					ifp->idev->cnf.dad_transmits *
4400 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4401 
4402 				if (age >= ifp->prefered_lft - regen_advance) {
4403 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4404 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4405 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4406 					if (!ifp->regen_count && ifpub) {
4407 						ifp->regen_count++;
4408 						in6_ifa_hold(ifp);
4409 						in6_ifa_hold(ifpub);
4410 						spin_unlock(&ifp->lock);
4411 
4412 						spin_lock(&ifpub->lock);
4413 						ifpub->regen_count = 0;
4414 						spin_unlock(&ifpub->lock);
4415 						rcu_read_unlock_bh();
4416 						ipv6_create_tempaddr(ifpub, ifp, true);
4417 						in6_ifa_put(ifpub);
4418 						in6_ifa_put(ifp);
4419 						rcu_read_lock_bh();
4420 						goto restart;
4421 					}
4422 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4423 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4424 				spin_unlock(&ifp->lock);
4425 			} else {
4426 				/* ifp->prefered_lft <= ifp->valid_lft */
4427 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4428 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4429 				spin_unlock(&ifp->lock);
4430 			}
4431 		}
4432 	}
4433 
4434 	next_sec = round_jiffies_up(next);
4435 	next_sched = next;
4436 
4437 	/* If rounded timeout is accurate enough, accept it. */
4438 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4439 		next_sched = next_sec;
4440 
4441 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4442 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4443 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4444 
4445 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4446 		 now, next, next_sec, next_sched);
4447 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4448 	rcu_read_unlock_bh();
4449 }
4450 
4451 static void addrconf_verify_work(struct work_struct *w)
4452 {
4453 	rtnl_lock();
4454 	addrconf_verify_rtnl();
4455 	rtnl_unlock();
4456 }
4457 
4458 static void addrconf_verify(void)
4459 {
4460 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4461 }
4462 
4463 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4464 				     struct in6_addr **peer_pfx)
4465 {
4466 	struct in6_addr *pfx = NULL;
4467 
4468 	*peer_pfx = NULL;
4469 
4470 	if (addr)
4471 		pfx = nla_data(addr);
4472 
4473 	if (local) {
4474 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4475 			*peer_pfx = pfx;
4476 		pfx = nla_data(local);
4477 	}
4478 
4479 	return pfx;
4480 }
4481 
4482 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4483 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4484 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4485 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4486 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4487 };
4488 
4489 static int
4490 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4491 		  struct netlink_ext_ack *extack)
4492 {
4493 	struct net *net = sock_net(skb->sk);
4494 	struct ifaddrmsg *ifm;
4495 	struct nlattr *tb[IFA_MAX+1];
4496 	struct in6_addr *pfx, *peer_pfx;
4497 	u32 ifa_flags;
4498 	int err;
4499 
4500 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4501 			  extack);
4502 	if (err < 0)
4503 		return err;
4504 
4505 	ifm = nlmsg_data(nlh);
4506 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4507 	if (!pfx)
4508 		return -EINVAL;
4509 
4510 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4511 
4512 	/* We ignore other flags so far. */
4513 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4514 
4515 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4516 			      ifm->ifa_prefixlen);
4517 }
4518 
4519 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u32 ifa_flags,
4520 			     u32 prefered_lft, u32 valid_lft)
4521 {
4522 	u32 flags;
4523 	clock_t expires;
4524 	unsigned long timeout;
4525 	bool was_managetempaddr;
4526 	bool had_prefixroute;
4527 
4528 	ASSERT_RTNL();
4529 
4530 	if (!valid_lft || (prefered_lft > valid_lft))
4531 		return -EINVAL;
4532 
4533 	if (ifa_flags & IFA_F_MANAGETEMPADDR &&
4534 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4535 		return -EINVAL;
4536 
4537 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4538 		ifa_flags &= ~IFA_F_OPTIMISTIC;
4539 
4540 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
4541 	if (addrconf_finite_timeout(timeout)) {
4542 		expires = jiffies_to_clock_t(timeout * HZ);
4543 		valid_lft = timeout;
4544 		flags = RTF_EXPIRES;
4545 	} else {
4546 		expires = 0;
4547 		flags = 0;
4548 		ifa_flags |= IFA_F_PERMANENT;
4549 	}
4550 
4551 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
4552 	if (addrconf_finite_timeout(timeout)) {
4553 		if (timeout == 0)
4554 			ifa_flags |= IFA_F_DEPRECATED;
4555 		prefered_lft = timeout;
4556 	}
4557 
4558 	spin_lock_bh(&ifp->lock);
4559 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4560 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4561 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4562 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4563 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4564 			IFA_F_NOPREFIXROUTE);
4565 	ifp->flags |= ifa_flags;
4566 	ifp->tstamp = jiffies;
4567 	ifp->valid_lft = valid_lft;
4568 	ifp->prefered_lft = prefered_lft;
4569 
4570 	spin_unlock_bh(&ifp->lock);
4571 	if (!(ifp->flags&IFA_F_TENTATIVE))
4572 		ipv6_ifa_notify(0, ifp);
4573 
4574 	if (!(ifa_flags & IFA_F_NOPREFIXROUTE)) {
4575 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4576 				      ifp->idev->dev, expires, flags,
4577 				      GFP_KERNEL);
4578 	} else if (had_prefixroute) {
4579 		enum cleanup_prefix_rt_t action;
4580 		unsigned long rt_expires;
4581 
4582 		write_lock_bh(&ifp->idev->lock);
4583 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4584 		write_unlock_bh(&ifp->idev->lock);
4585 
4586 		if (action != CLEANUP_PREFIX_RT_NOP) {
4587 			cleanup_prefix_route(ifp, rt_expires,
4588 				action == CLEANUP_PREFIX_RT_DEL);
4589 		}
4590 	}
4591 
4592 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4593 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4594 			valid_lft = prefered_lft = 0;
4595 		manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
4596 				 !was_managetempaddr, jiffies);
4597 	}
4598 
4599 	addrconf_verify_rtnl();
4600 
4601 	return 0;
4602 }
4603 
4604 static int
4605 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4606 		  struct netlink_ext_ack *extack)
4607 {
4608 	struct net *net = sock_net(skb->sk);
4609 	struct ifaddrmsg *ifm;
4610 	struct nlattr *tb[IFA_MAX+1];
4611 	struct in6_addr *pfx, *peer_pfx;
4612 	struct inet6_ifaddr *ifa;
4613 	struct net_device *dev;
4614 	struct inet6_dev *idev;
4615 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
4616 	u32 ifa_flags;
4617 	int err;
4618 
4619 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4620 			  extack);
4621 	if (err < 0)
4622 		return err;
4623 
4624 	ifm = nlmsg_data(nlh);
4625 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4626 	if (!pfx)
4627 		return -EINVAL;
4628 
4629 	if (tb[IFA_CACHEINFO]) {
4630 		struct ifa_cacheinfo *ci;
4631 
4632 		ci = nla_data(tb[IFA_CACHEINFO]);
4633 		valid_lft = ci->ifa_valid;
4634 		preferred_lft = ci->ifa_prefered;
4635 	} else {
4636 		preferred_lft = INFINITY_LIFE_TIME;
4637 		valid_lft = INFINITY_LIFE_TIME;
4638 	}
4639 
4640 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4641 	if (!dev)
4642 		return -ENODEV;
4643 
4644 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4645 
4646 	/* We ignore other flags so far. */
4647 	ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4648 		     IFA_F_NOPREFIXROUTE | IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4649 
4650 	idev = ipv6_find_idev(dev);
4651 	if (IS_ERR(idev))
4652 		return PTR_ERR(idev);
4653 
4654 	if (!ipv6_allow_optimistic_dad(net, idev))
4655 		ifa_flags &= ~IFA_F_OPTIMISTIC;
4656 
4657 	if (ifa_flags & IFA_F_NODAD && ifa_flags & IFA_F_OPTIMISTIC) {
4658 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4659 		return -EINVAL;
4660 	}
4661 
4662 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
4663 	if (!ifa) {
4664 		/*
4665 		 * It would be best to check for !NLM_F_CREATE here but
4666 		 * userspace already relies on not having to provide this.
4667 		 */
4668 		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,
4669 				      ifm->ifa_prefixlen, ifa_flags,
4670 				      preferred_lft, valid_lft, extack);
4671 	}
4672 
4673 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4674 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4675 		err = -EEXIST;
4676 	else
4677 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
4678 
4679 	in6_ifa_put(ifa);
4680 
4681 	return err;
4682 }
4683 
4684 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4685 			  u8 scope, int ifindex)
4686 {
4687 	struct ifaddrmsg *ifm;
4688 
4689 	ifm = nlmsg_data(nlh);
4690 	ifm->ifa_family = AF_INET6;
4691 	ifm->ifa_prefixlen = prefixlen;
4692 	ifm->ifa_flags = flags;
4693 	ifm->ifa_scope = scope;
4694 	ifm->ifa_index = ifindex;
4695 }
4696 
4697 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4698 			 unsigned long tstamp, u32 preferred, u32 valid)
4699 {
4700 	struct ifa_cacheinfo ci;
4701 
4702 	ci.cstamp = cstamp_delta(cstamp);
4703 	ci.tstamp = cstamp_delta(tstamp);
4704 	ci.ifa_prefered = preferred;
4705 	ci.ifa_valid = valid;
4706 
4707 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4708 }
4709 
4710 static inline int rt_scope(int ifa_scope)
4711 {
4712 	if (ifa_scope & IFA_HOST)
4713 		return RT_SCOPE_HOST;
4714 	else if (ifa_scope & IFA_LINK)
4715 		return RT_SCOPE_LINK;
4716 	else if (ifa_scope & IFA_SITE)
4717 		return RT_SCOPE_SITE;
4718 	else
4719 		return RT_SCOPE_UNIVERSE;
4720 }
4721 
4722 static inline int inet6_ifaddr_msgsize(void)
4723 {
4724 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4725 	       + nla_total_size(16) /* IFA_LOCAL */
4726 	       + nla_total_size(16) /* IFA_ADDRESS */
4727 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4728 	       + nla_total_size(4)  /* IFA_FLAGS */;
4729 }
4730 
4731 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4732 			     u32 portid, u32 seq, int event, unsigned int flags)
4733 {
4734 	struct nlmsghdr  *nlh;
4735 	u32 preferred, valid;
4736 
4737 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4738 	if (!nlh)
4739 		return -EMSGSIZE;
4740 
4741 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4742 		      ifa->idev->dev->ifindex);
4743 
4744 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4745 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4746 		preferred = ifa->prefered_lft;
4747 		valid = ifa->valid_lft;
4748 		if (preferred != INFINITY_LIFE_TIME) {
4749 			long tval = (jiffies - ifa->tstamp)/HZ;
4750 			if (preferred > tval)
4751 				preferred -= tval;
4752 			else
4753 				preferred = 0;
4754 			if (valid != INFINITY_LIFE_TIME) {
4755 				if (valid > tval)
4756 					valid -= tval;
4757 				else
4758 					valid = 0;
4759 			}
4760 		}
4761 	} else {
4762 		preferred = INFINITY_LIFE_TIME;
4763 		valid = INFINITY_LIFE_TIME;
4764 	}
4765 
4766 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4767 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4768 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4769 			goto error;
4770 	} else
4771 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4772 			goto error;
4773 
4774 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4775 		goto error;
4776 
4777 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4778 		goto error;
4779 
4780 	nlmsg_end(skb, nlh);
4781 	return 0;
4782 
4783 error:
4784 	nlmsg_cancel(skb, nlh);
4785 	return -EMSGSIZE;
4786 }
4787 
4788 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4789 				u32 portid, u32 seq, int event, u16 flags)
4790 {
4791 	struct nlmsghdr  *nlh;
4792 	u8 scope = RT_SCOPE_UNIVERSE;
4793 	int ifindex = ifmca->idev->dev->ifindex;
4794 
4795 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4796 		scope = RT_SCOPE_SITE;
4797 
4798 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4799 	if (!nlh)
4800 		return -EMSGSIZE;
4801 
4802 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4803 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4804 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4805 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4806 		nlmsg_cancel(skb, nlh);
4807 		return -EMSGSIZE;
4808 	}
4809 
4810 	nlmsg_end(skb, nlh);
4811 	return 0;
4812 }
4813 
4814 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4815 				u32 portid, u32 seq, int event, unsigned int flags)
4816 {
4817 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4818 	int ifindex = dev ? dev->ifindex : 1;
4819 	struct nlmsghdr  *nlh;
4820 	u8 scope = RT_SCOPE_UNIVERSE;
4821 
4822 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4823 		scope = RT_SCOPE_SITE;
4824 
4825 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
4826 	if (!nlh)
4827 		return -EMSGSIZE;
4828 
4829 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4830 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4831 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4832 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4833 		nlmsg_cancel(skb, nlh);
4834 		return -EMSGSIZE;
4835 	}
4836 
4837 	nlmsg_end(skb, nlh);
4838 	return 0;
4839 }
4840 
4841 enum addr_type_t {
4842 	UNICAST_ADDR,
4843 	MULTICAST_ADDR,
4844 	ANYCAST_ADDR,
4845 };
4846 
4847 /* called with rcu_read_lock() */
4848 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4849 			  struct netlink_callback *cb, enum addr_type_t type,
4850 			  int s_ip_idx, int *p_ip_idx)
4851 {
4852 	struct ifmcaddr6 *ifmca;
4853 	struct ifacaddr6 *ifaca;
4854 	int err = 1;
4855 	int ip_idx = *p_ip_idx;
4856 
4857 	read_lock_bh(&idev->lock);
4858 	switch (type) {
4859 	case UNICAST_ADDR: {
4860 		struct inet6_ifaddr *ifa;
4861 
4862 		/* unicast address incl. temp addr */
4863 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4864 			if (++ip_idx < s_ip_idx)
4865 				continue;
4866 			err = inet6_fill_ifaddr(skb, ifa,
4867 						NETLINK_CB(cb->skb).portid,
4868 						cb->nlh->nlmsg_seq,
4869 						RTM_NEWADDR,
4870 						NLM_F_MULTI);
4871 			if (err < 0)
4872 				break;
4873 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4874 		}
4875 		break;
4876 	}
4877 	case MULTICAST_ADDR:
4878 		/* multicast address */
4879 		for (ifmca = idev->mc_list; ifmca;
4880 		     ifmca = ifmca->next, ip_idx++) {
4881 			if (ip_idx < s_ip_idx)
4882 				continue;
4883 			err = inet6_fill_ifmcaddr(skb, ifmca,
4884 						  NETLINK_CB(cb->skb).portid,
4885 						  cb->nlh->nlmsg_seq,
4886 						  RTM_GETMULTICAST,
4887 						  NLM_F_MULTI);
4888 			if (err < 0)
4889 				break;
4890 		}
4891 		break;
4892 	case ANYCAST_ADDR:
4893 		/* anycast address */
4894 		for (ifaca = idev->ac_list; ifaca;
4895 		     ifaca = ifaca->aca_next, ip_idx++) {
4896 			if (ip_idx < s_ip_idx)
4897 				continue;
4898 			err = inet6_fill_ifacaddr(skb, ifaca,
4899 						  NETLINK_CB(cb->skb).portid,
4900 						  cb->nlh->nlmsg_seq,
4901 						  RTM_GETANYCAST,
4902 						  NLM_F_MULTI);
4903 			if (err < 0)
4904 				break;
4905 		}
4906 		break;
4907 	default:
4908 		break;
4909 	}
4910 	read_unlock_bh(&idev->lock);
4911 	*p_ip_idx = ip_idx;
4912 	return err;
4913 }
4914 
4915 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
4916 			   enum addr_type_t type)
4917 {
4918 	struct net *net = sock_net(skb->sk);
4919 	int h, s_h;
4920 	int idx, ip_idx;
4921 	int s_idx, s_ip_idx;
4922 	struct net_device *dev;
4923 	struct inet6_dev *idev;
4924 	struct hlist_head *head;
4925 
4926 	s_h = cb->args[0];
4927 	s_idx = idx = cb->args[1];
4928 	s_ip_idx = ip_idx = cb->args[2];
4929 
4930 	rcu_read_lock();
4931 	cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^ net->dev_base_seq;
4932 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4933 		idx = 0;
4934 		head = &net->dev_index_head[h];
4935 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
4936 			if (idx < s_idx)
4937 				goto cont;
4938 			if (h > s_h || idx > s_idx)
4939 				s_ip_idx = 0;
4940 			ip_idx = 0;
4941 			idev = __in6_dev_get(dev);
4942 			if (!idev)
4943 				goto cont;
4944 
4945 			if (in6_dump_addrs(idev, skb, cb, type,
4946 					   s_ip_idx, &ip_idx) < 0)
4947 				goto done;
4948 cont:
4949 			idx++;
4950 		}
4951 	}
4952 done:
4953 	rcu_read_unlock();
4954 	cb->args[0] = h;
4955 	cb->args[1] = idx;
4956 	cb->args[2] = ip_idx;
4957 
4958 	return skb->len;
4959 }
4960 
4961 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
4962 {
4963 	enum addr_type_t type = UNICAST_ADDR;
4964 
4965 	return inet6_dump_addr(skb, cb, type);
4966 }
4967 
4968 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
4969 {
4970 	enum addr_type_t type = MULTICAST_ADDR;
4971 
4972 	return inet6_dump_addr(skb, cb, type);
4973 }
4974 
4975 
4976 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
4977 {
4978 	enum addr_type_t type = ANYCAST_ADDR;
4979 
4980 	return inet6_dump_addr(skb, cb, type);
4981 }
4982 
4983 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
4984 			     struct netlink_ext_ack *extack)
4985 {
4986 	struct net *net = sock_net(in_skb->sk);
4987 	struct ifaddrmsg *ifm;
4988 	struct nlattr *tb[IFA_MAX+1];
4989 	struct in6_addr *addr = NULL, *peer;
4990 	struct net_device *dev = NULL;
4991 	struct inet6_ifaddr *ifa;
4992 	struct sk_buff *skb;
4993 	int err;
4994 
4995 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4996 			  extack);
4997 	if (err < 0)
4998 		return err;
4999 
5000 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5001 	if (!addr)
5002 		return -EINVAL;
5003 
5004 	ifm = nlmsg_data(nlh);
5005 	if (ifm->ifa_index)
5006 		dev = dev_get_by_index(net, ifm->ifa_index);
5007 
5008 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
5009 	if (!ifa) {
5010 		err = -EADDRNOTAVAIL;
5011 		goto errout;
5012 	}
5013 
5014 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5015 	if (!skb) {
5016 		err = -ENOBUFS;
5017 		goto errout_ifa;
5018 	}
5019 
5020 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
5021 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
5022 	if (err < 0) {
5023 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5024 		WARN_ON(err == -EMSGSIZE);
5025 		kfree_skb(skb);
5026 		goto errout_ifa;
5027 	}
5028 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
5029 errout_ifa:
5030 	in6_ifa_put(ifa);
5031 errout:
5032 	if (dev)
5033 		dev_put(dev);
5034 	return err;
5035 }
5036 
5037 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5038 {
5039 	struct sk_buff *skb;
5040 	struct net *net = dev_net(ifa->idev->dev);
5041 	int err = -ENOBUFS;
5042 
5043 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5044 	if (!skb)
5045 		goto errout;
5046 
5047 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
5048 	if (err < 0) {
5049 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5050 		WARN_ON(err == -EMSGSIZE);
5051 		kfree_skb(skb);
5052 		goto errout;
5053 	}
5054 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5055 	return;
5056 errout:
5057 	if (err < 0)
5058 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5059 }
5060 
5061 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5062 				__s32 *array, int bytes)
5063 {
5064 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5065 
5066 	memset(array, 0, bytes);
5067 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5068 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5069 	array[DEVCONF_MTU6] = cnf->mtu6;
5070 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5071 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5072 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5073 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5074 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5075 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5076 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5077 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5078 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5079 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5080 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5081 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5082 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5083 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5084 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5085 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5086 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5087 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5088 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5089 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5090 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5091 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5092 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5093 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5094 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5095 #ifdef CONFIG_IPV6_ROUTER_PREF
5096 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5097 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5098 		jiffies_to_msecs(cnf->rtr_probe_interval);
5099 #ifdef CONFIG_IPV6_ROUTE_INFO
5100 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5101 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5102 #endif
5103 #endif
5104 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5105 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5106 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5107 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5108 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5109 #endif
5110 #ifdef CONFIG_IPV6_MROUTE
5111 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5112 #endif
5113 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5114 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5115 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5116 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5117 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5118 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5119 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5120 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5121 	/* we omit DEVCONF_STABLE_SECRET for now */
5122 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5123 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5124 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5125 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5126 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5127 #ifdef CONFIG_IPV6_SEG6_HMAC
5128 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5129 #endif
5130 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5131 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5132 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5133 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5134 }
5135 
5136 static inline size_t inet6_ifla6_size(void)
5137 {
5138 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5139 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5140 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5141 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5142 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5143 	     + nla_total_size(sizeof(struct in6_addr)); /* IFLA_INET6_TOKEN */
5144 }
5145 
5146 static inline size_t inet6_if_nlmsg_size(void)
5147 {
5148 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5149 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5150 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5151 	       + nla_total_size(4) /* IFLA_MTU */
5152 	       + nla_total_size(4) /* IFLA_LINK */
5153 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5154 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5155 }
5156 
5157 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5158 					int bytes)
5159 {
5160 	int i;
5161 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5162 	BUG_ON(pad < 0);
5163 
5164 	/* Use put_unaligned() because stats may not be aligned for u64. */
5165 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5166 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5167 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5168 
5169 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5170 }
5171 
5172 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5173 					int bytes, size_t syncpoff)
5174 {
5175 	int i, c;
5176 	u64 buff[IPSTATS_MIB_MAX];
5177 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5178 
5179 	BUG_ON(pad < 0);
5180 
5181 	memset(buff, 0, sizeof(buff));
5182 	buff[0] = IPSTATS_MIB_MAX;
5183 
5184 	for_each_possible_cpu(c) {
5185 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5186 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5187 	}
5188 
5189 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5190 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5191 }
5192 
5193 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5194 			     int bytes)
5195 {
5196 	switch (attrtype) {
5197 	case IFLA_INET6_STATS:
5198 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5199 				     offsetof(struct ipstats_mib, syncp));
5200 		break;
5201 	case IFLA_INET6_ICMP6STATS:
5202 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5203 		break;
5204 	}
5205 }
5206 
5207 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5208 				  u32 ext_filter_mask)
5209 {
5210 	struct nlattr *nla;
5211 	struct ifla_cacheinfo ci;
5212 
5213 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5214 		goto nla_put_failure;
5215 	ci.max_reasm_len = IPV6_MAXPLEN;
5216 	ci.tstamp = cstamp_delta(idev->tstamp);
5217 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5218 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5219 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5220 		goto nla_put_failure;
5221 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5222 	if (!nla)
5223 		goto nla_put_failure;
5224 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5225 
5226 	/* XXX - MC not implemented */
5227 
5228 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5229 		return 0;
5230 
5231 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5232 	if (!nla)
5233 		goto nla_put_failure;
5234 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5235 
5236 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5237 	if (!nla)
5238 		goto nla_put_failure;
5239 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5240 
5241 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5242 	if (!nla)
5243 		goto nla_put_failure;
5244 
5245 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5246 		goto nla_put_failure;
5247 
5248 	read_lock_bh(&idev->lock);
5249 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5250 	read_unlock_bh(&idev->lock);
5251 
5252 	return 0;
5253 
5254 nla_put_failure:
5255 	return -EMSGSIZE;
5256 }
5257 
5258 static size_t inet6_get_link_af_size(const struct net_device *dev,
5259 				     u32 ext_filter_mask)
5260 {
5261 	if (!__in6_dev_get(dev))
5262 		return 0;
5263 
5264 	return inet6_ifla6_size();
5265 }
5266 
5267 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5268 			      u32 ext_filter_mask)
5269 {
5270 	struct inet6_dev *idev = __in6_dev_get(dev);
5271 
5272 	if (!idev)
5273 		return -ENODATA;
5274 
5275 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5276 		return -EMSGSIZE;
5277 
5278 	return 0;
5279 }
5280 
5281 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5282 {
5283 	struct inet6_ifaddr *ifp;
5284 	struct net_device *dev = idev->dev;
5285 	bool clear_token, update_rs = false;
5286 	struct in6_addr ll_addr;
5287 
5288 	ASSERT_RTNL();
5289 
5290 	if (!token)
5291 		return -EINVAL;
5292 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5293 		return -EINVAL;
5294 	if (!ipv6_accept_ra(idev))
5295 		return -EINVAL;
5296 	if (idev->cnf.rtr_solicits == 0)
5297 		return -EINVAL;
5298 
5299 	write_lock_bh(&idev->lock);
5300 
5301 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5302 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5303 
5304 	write_unlock_bh(&idev->lock);
5305 
5306 	clear_token = ipv6_addr_any(token);
5307 	if (clear_token)
5308 		goto update_lft;
5309 
5310 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5311 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5312 			     IFA_F_OPTIMISTIC)) {
5313 		/* If we're not ready, then normal ifup will take care
5314 		 * of this. Otherwise, we need to request our rs here.
5315 		 */
5316 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5317 		update_rs = true;
5318 	}
5319 
5320 update_lft:
5321 	write_lock_bh(&idev->lock);
5322 
5323 	if (update_rs) {
5324 		idev->if_flags |= IF_RS_SENT;
5325 		idev->rs_interval = rfc3315_s14_backoff_init(
5326 			idev->cnf.rtr_solicit_interval);
5327 		idev->rs_probes = 1;
5328 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5329 	}
5330 
5331 	/* Well, that's kinda nasty ... */
5332 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5333 		spin_lock(&ifp->lock);
5334 		if (ifp->tokenized) {
5335 			ifp->valid_lft = 0;
5336 			ifp->prefered_lft = 0;
5337 		}
5338 		spin_unlock(&ifp->lock);
5339 	}
5340 
5341 	write_unlock_bh(&idev->lock);
5342 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5343 	addrconf_verify_rtnl();
5344 	return 0;
5345 }
5346 
5347 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5348 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5349 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5350 };
5351 
5352 static int inet6_validate_link_af(const struct net_device *dev,
5353 				  const struct nlattr *nla)
5354 {
5355 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5356 
5357 	if (dev && !__in6_dev_get(dev))
5358 		return -EAFNOSUPPORT;
5359 
5360 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5361 				NULL);
5362 }
5363 
5364 static int check_addr_gen_mode(int mode)
5365 {
5366 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5367 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5368 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5369 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5370 		return -EINVAL;
5371 	return 1;
5372 }
5373 
5374 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5375 				int mode)
5376 {
5377 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5378 	    !idev->cnf.stable_secret.initialized &&
5379 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5380 		return -EINVAL;
5381 	return 1;
5382 }
5383 
5384 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5385 {
5386 	int err = -EINVAL;
5387 	struct inet6_dev *idev = __in6_dev_get(dev);
5388 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5389 
5390 	if (!idev)
5391 		return -EAFNOSUPPORT;
5392 
5393 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5394 		BUG();
5395 
5396 	if (tb[IFLA_INET6_TOKEN]) {
5397 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5398 		if (err)
5399 			return err;
5400 	}
5401 
5402 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5403 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5404 
5405 		if (check_addr_gen_mode(mode) < 0 ||
5406 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5407 			return -EINVAL;
5408 
5409 		idev->cnf.addr_gen_mode = mode;
5410 		err = 0;
5411 	}
5412 
5413 	return err;
5414 }
5415 
5416 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5417 			     u32 portid, u32 seq, int event, unsigned int flags)
5418 {
5419 	struct net_device *dev = idev->dev;
5420 	struct ifinfomsg *hdr;
5421 	struct nlmsghdr *nlh;
5422 	void *protoinfo;
5423 
5424 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5425 	if (!nlh)
5426 		return -EMSGSIZE;
5427 
5428 	hdr = nlmsg_data(nlh);
5429 	hdr->ifi_family = AF_INET6;
5430 	hdr->__ifi_pad = 0;
5431 	hdr->ifi_type = dev->type;
5432 	hdr->ifi_index = dev->ifindex;
5433 	hdr->ifi_flags = dev_get_flags(dev);
5434 	hdr->ifi_change = 0;
5435 
5436 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5437 	    (dev->addr_len &&
5438 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5439 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5440 	    (dev->ifindex != dev_get_iflink(dev) &&
5441 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5442 	    nla_put_u8(skb, IFLA_OPERSTATE,
5443 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5444 		goto nla_put_failure;
5445 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5446 	if (!protoinfo)
5447 		goto nla_put_failure;
5448 
5449 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5450 		goto nla_put_failure;
5451 
5452 	nla_nest_end(skb, protoinfo);
5453 	nlmsg_end(skb, nlh);
5454 	return 0;
5455 
5456 nla_put_failure:
5457 	nlmsg_cancel(skb, nlh);
5458 	return -EMSGSIZE;
5459 }
5460 
5461 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5462 {
5463 	struct net *net = sock_net(skb->sk);
5464 	int h, s_h;
5465 	int idx = 0, s_idx;
5466 	struct net_device *dev;
5467 	struct inet6_dev *idev;
5468 	struct hlist_head *head;
5469 
5470 	s_h = cb->args[0];
5471 	s_idx = cb->args[1];
5472 
5473 	rcu_read_lock();
5474 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5475 		idx = 0;
5476 		head = &net->dev_index_head[h];
5477 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5478 			if (idx < s_idx)
5479 				goto cont;
5480 			idev = __in6_dev_get(dev);
5481 			if (!idev)
5482 				goto cont;
5483 			if (inet6_fill_ifinfo(skb, idev,
5484 					      NETLINK_CB(cb->skb).portid,
5485 					      cb->nlh->nlmsg_seq,
5486 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5487 				goto out;
5488 cont:
5489 			idx++;
5490 		}
5491 	}
5492 out:
5493 	rcu_read_unlock();
5494 	cb->args[1] = idx;
5495 	cb->args[0] = h;
5496 
5497 	return skb->len;
5498 }
5499 
5500 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5501 {
5502 	struct sk_buff *skb;
5503 	struct net *net = dev_net(idev->dev);
5504 	int err = -ENOBUFS;
5505 
5506 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5507 	if (!skb)
5508 		goto errout;
5509 
5510 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5511 	if (err < 0) {
5512 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5513 		WARN_ON(err == -EMSGSIZE);
5514 		kfree_skb(skb);
5515 		goto errout;
5516 	}
5517 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5518 	return;
5519 errout:
5520 	if (err < 0)
5521 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5522 }
5523 
5524 static inline size_t inet6_prefix_nlmsg_size(void)
5525 {
5526 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5527 	       + nla_total_size(sizeof(struct in6_addr))
5528 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5529 }
5530 
5531 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5532 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5533 			     int event, unsigned int flags)
5534 {
5535 	struct prefixmsg *pmsg;
5536 	struct nlmsghdr *nlh;
5537 	struct prefix_cacheinfo	ci;
5538 
5539 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5540 	if (!nlh)
5541 		return -EMSGSIZE;
5542 
5543 	pmsg = nlmsg_data(nlh);
5544 	pmsg->prefix_family = AF_INET6;
5545 	pmsg->prefix_pad1 = 0;
5546 	pmsg->prefix_pad2 = 0;
5547 	pmsg->prefix_ifindex = idev->dev->ifindex;
5548 	pmsg->prefix_len = pinfo->prefix_len;
5549 	pmsg->prefix_type = pinfo->type;
5550 	pmsg->prefix_pad3 = 0;
5551 	pmsg->prefix_flags = 0;
5552 	if (pinfo->onlink)
5553 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5554 	if (pinfo->autoconf)
5555 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5556 
5557 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5558 		goto nla_put_failure;
5559 	ci.preferred_time = ntohl(pinfo->prefered);
5560 	ci.valid_time = ntohl(pinfo->valid);
5561 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5562 		goto nla_put_failure;
5563 	nlmsg_end(skb, nlh);
5564 	return 0;
5565 
5566 nla_put_failure:
5567 	nlmsg_cancel(skb, nlh);
5568 	return -EMSGSIZE;
5569 }
5570 
5571 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5572 			 struct prefix_info *pinfo)
5573 {
5574 	struct sk_buff *skb;
5575 	struct net *net = dev_net(idev->dev);
5576 	int err = -ENOBUFS;
5577 
5578 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5579 	if (!skb)
5580 		goto errout;
5581 
5582 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5583 	if (err < 0) {
5584 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5585 		WARN_ON(err == -EMSGSIZE);
5586 		kfree_skb(skb);
5587 		goto errout;
5588 	}
5589 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5590 	return;
5591 errout:
5592 	if (err < 0)
5593 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5594 }
5595 
5596 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5597 {
5598 	struct net *net = dev_net(ifp->idev->dev);
5599 
5600 	if (event)
5601 		ASSERT_RTNL();
5602 
5603 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5604 
5605 	switch (event) {
5606 	case RTM_NEWADDR:
5607 		/*
5608 		 * If the address was optimistic
5609 		 * we inserted the route at the start of
5610 		 * our DAD process, so we don't need
5611 		 * to do it again
5612 		 */
5613 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5614 			ip6_ins_rt(net, ifp->rt);
5615 		if (ifp->idev->cnf.forwarding)
5616 			addrconf_join_anycast(ifp);
5617 		if (!ipv6_addr_any(&ifp->peer_addr))
5618 			addrconf_prefix_route(&ifp->peer_addr, 128,
5619 					      ifp->idev->dev, 0, 0,
5620 					      GFP_ATOMIC);
5621 		break;
5622 	case RTM_DELADDR:
5623 		if (ifp->idev->cnf.forwarding)
5624 			addrconf_leave_anycast(ifp);
5625 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5626 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5627 			struct fib6_info *rt;
5628 
5629 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5630 						       ifp->idev->dev, 0, 0);
5631 			if (rt)
5632 				ip6_del_rt(net, rt);
5633 		}
5634 		if (ifp->rt) {
5635 			ip6_del_rt(net, ifp->rt);
5636 			ifp->rt = NULL;
5637 		}
5638 		rt_genid_bump_ipv6(net);
5639 		break;
5640 	}
5641 	atomic_inc(&net->ipv6.dev_addr_genid);
5642 }
5643 
5644 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5645 {
5646 	rcu_read_lock_bh();
5647 	if (likely(ifp->idev->dead == 0))
5648 		__ipv6_ifa_notify(event, ifp);
5649 	rcu_read_unlock_bh();
5650 }
5651 
5652 #ifdef CONFIG_SYSCTL
5653 
5654 static
5655 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5656 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5657 {
5658 	int *valp = ctl->data;
5659 	int val = *valp;
5660 	loff_t pos = *ppos;
5661 	struct ctl_table lctl;
5662 	int ret;
5663 
5664 	/*
5665 	 * ctl->data points to idev->cnf.forwarding, we should
5666 	 * not modify it until we get the rtnl lock.
5667 	 */
5668 	lctl = *ctl;
5669 	lctl.data = &val;
5670 
5671 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5672 
5673 	if (write)
5674 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5675 	if (ret)
5676 		*ppos = pos;
5677 	return ret;
5678 }
5679 
5680 static
5681 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5682 			void __user *buffer, size_t *lenp, loff_t *ppos)
5683 {
5684 	struct inet6_dev *idev = ctl->extra1;
5685 	int min_mtu = IPV6_MIN_MTU;
5686 	struct ctl_table lctl;
5687 
5688 	lctl = *ctl;
5689 	lctl.extra1 = &min_mtu;
5690 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5691 
5692 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5693 }
5694 
5695 static void dev_disable_change(struct inet6_dev *idev)
5696 {
5697 	struct netdev_notifier_info info;
5698 
5699 	if (!idev || !idev->dev)
5700 		return;
5701 
5702 	netdev_notifier_info_init(&info, idev->dev);
5703 	if (idev->cnf.disable_ipv6)
5704 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5705 	else
5706 		addrconf_notify(NULL, NETDEV_UP, &info);
5707 }
5708 
5709 static void addrconf_disable_change(struct net *net, __s32 newf)
5710 {
5711 	struct net_device *dev;
5712 	struct inet6_dev *idev;
5713 
5714 	for_each_netdev(net, dev) {
5715 		idev = __in6_dev_get(dev);
5716 		if (idev) {
5717 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5718 			idev->cnf.disable_ipv6 = newf;
5719 			if (changed)
5720 				dev_disable_change(idev);
5721 		}
5722 	}
5723 }
5724 
5725 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5726 {
5727 	struct net *net;
5728 	int old;
5729 
5730 	if (!rtnl_trylock())
5731 		return restart_syscall();
5732 
5733 	net = (struct net *)table->extra2;
5734 	old = *p;
5735 	*p = newf;
5736 
5737 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5738 		rtnl_unlock();
5739 		return 0;
5740 	}
5741 
5742 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5743 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5744 		addrconf_disable_change(net, newf);
5745 	} else if ((!newf) ^ (!old))
5746 		dev_disable_change((struct inet6_dev *)table->extra1);
5747 
5748 	rtnl_unlock();
5749 	return 0;
5750 }
5751 
5752 static
5753 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5754 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5755 {
5756 	int *valp = ctl->data;
5757 	int val = *valp;
5758 	loff_t pos = *ppos;
5759 	struct ctl_table lctl;
5760 	int ret;
5761 
5762 	/*
5763 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5764 	 * not modify it until we get the rtnl lock.
5765 	 */
5766 	lctl = *ctl;
5767 	lctl.data = &val;
5768 
5769 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5770 
5771 	if (write)
5772 		ret = addrconf_disable_ipv6(ctl, valp, val);
5773 	if (ret)
5774 		*ppos = pos;
5775 	return ret;
5776 }
5777 
5778 static
5779 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5780 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5781 {
5782 	int *valp = ctl->data;
5783 	int ret;
5784 	int old, new;
5785 
5786 	old = *valp;
5787 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5788 	new = *valp;
5789 
5790 	if (write && old != new) {
5791 		struct net *net = ctl->extra2;
5792 
5793 		if (!rtnl_trylock())
5794 			return restart_syscall();
5795 
5796 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5797 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5798 						     NETCONFA_PROXY_NEIGH,
5799 						     NETCONFA_IFINDEX_DEFAULT,
5800 						     net->ipv6.devconf_dflt);
5801 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5802 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5803 						     NETCONFA_PROXY_NEIGH,
5804 						     NETCONFA_IFINDEX_ALL,
5805 						     net->ipv6.devconf_all);
5806 		else {
5807 			struct inet6_dev *idev = ctl->extra1;
5808 
5809 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5810 						     NETCONFA_PROXY_NEIGH,
5811 						     idev->dev->ifindex,
5812 						     &idev->cnf);
5813 		}
5814 		rtnl_unlock();
5815 	}
5816 
5817 	return ret;
5818 }
5819 
5820 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5821 					 void __user *buffer, size_t *lenp,
5822 					 loff_t *ppos)
5823 {
5824 	int ret = 0;
5825 	int new_val;
5826 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5827 	struct net *net = (struct net *)ctl->extra2;
5828 
5829 	if (!rtnl_trylock())
5830 		return restart_syscall();
5831 
5832 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5833 
5834 	if (write) {
5835 		new_val = *((int *)ctl->data);
5836 
5837 		if (check_addr_gen_mode(new_val) < 0) {
5838 			ret = -EINVAL;
5839 			goto out;
5840 		}
5841 
5842 		/* request for default */
5843 		if (&net->ipv6.devconf_dflt->addr_gen_mode == ctl->data) {
5844 			ipv6_devconf_dflt.addr_gen_mode = new_val;
5845 
5846 		/* request for individual net device */
5847 		} else {
5848 			if (!idev)
5849 				goto out;
5850 
5851 			if (check_stable_privacy(idev, net, new_val) < 0) {
5852 				ret = -EINVAL;
5853 				goto out;
5854 			}
5855 
5856 			if (idev->cnf.addr_gen_mode != new_val) {
5857 				idev->cnf.addr_gen_mode = new_val;
5858 				addrconf_dev_config(idev->dev);
5859 			}
5860 		}
5861 	}
5862 
5863 out:
5864 	rtnl_unlock();
5865 
5866 	return ret;
5867 }
5868 
5869 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
5870 					 void __user *buffer, size_t *lenp,
5871 					 loff_t *ppos)
5872 {
5873 	int err;
5874 	struct in6_addr addr;
5875 	char str[IPV6_MAX_STRLEN];
5876 	struct ctl_table lctl = *ctl;
5877 	struct net *net = ctl->extra2;
5878 	struct ipv6_stable_secret *secret = ctl->data;
5879 
5880 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
5881 		return -EIO;
5882 
5883 	lctl.maxlen = IPV6_MAX_STRLEN;
5884 	lctl.data = str;
5885 
5886 	if (!rtnl_trylock())
5887 		return restart_syscall();
5888 
5889 	if (!write && !secret->initialized) {
5890 		err = -EIO;
5891 		goto out;
5892 	}
5893 
5894 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
5895 	if (err >= sizeof(str)) {
5896 		err = -EIO;
5897 		goto out;
5898 	}
5899 
5900 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
5901 	if (err || !write)
5902 		goto out;
5903 
5904 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
5905 		err = -EIO;
5906 		goto out;
5907 	}
5908 
5909 	secret->initialized = true;
5910 	secret->secret = addr;
5911 
5912 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
5913 		struct net_device *dev;
5914 
5915 		for_each_netdev(net, dev) {
5916 			struct inet6_dev *idev = __in6_dev_get(dev);
5917 
5918 			if (idev) {
5919 				idev->cnf.addr_gen_mode =
5920 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5921 			}
5922 		}
5923 	} else {
5924 		struct inet6_dev *idev = ctl->extra1;
5925 
5926 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
5927 	}
5928 
5929 out:
5930 	rtnl_unlock();
5931 
5932 	return err;
5933 }
5934 
5935 static
5936 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
5937 						int write,
5938 						void __user *buffer,
5939 						size_t *lenp,
5940 						loff_t *ppos)
5941 {
5942 	int *valp = ctl->data;
5943 	int val = *valp;
5944 	loff_t pos = *ppos;
5945 	struct ctl_table lctl;
5946 	int ret;
5947 
5948 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
5949 	 * we should not modify it until we get the rtnl lock.
5950 	 */
5951 	lctl = *ctl;
5952 	lctl.data = &val;
5953 
5954 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5955 
5956 	if (write)
5957 		ret = addrconf_fixup_linkdown(ctl, valp, val);
5958 	if (ret)
5959 		*ppos = pos;
5960 	return ret;
5961 }
5962 
5963 static
5964 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
5965 {
5966 	if (rt) {
5967 		if (action)
5968 			rt->dst.flags |= DST_NOPOLICY;
5969 		else
5970 			rt->dst.flags &= ~DST_NOPOLICY;
5971 	}
5972 }
5973 
5974 static
5975 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
5976 {
5977 	struct inet6_ifaddr *ifa;
5978 
5979 	read_lock_bh(&idev->lock);
5980 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
5981 		spin_lock(&ifa->lock);
5982 		if (ifa->rt) {
5983 			struct fib6_info *rt = ifa->rt;
5984 			int cpu;
5985 
5986 			rcu_read_lock();
5987 			ifa->rt->dst_nopolicy = val ? true : false;
5988 			if (rt->rt6i_pcpu) {
5989 				for_each_possible_cpu(cpu) {
5990 					struct rt6_info **rtp;
5991 
5992 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
5993 					addrconf_set_nopolicy(*rtp, val);
5994 				}
5995 			}
5996 			rcu_read_unlock();
5997 		}
5998 		spin_unlock(&ifa->lock);
5999 	}
6000 	read_unlock_bh(&idev->lock);
6001 }
6002 
6003 static
6004 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6005 {
6006 	struct inet6_dev *idev;
6007 	struct net *net;
6008 
6009 	if (!rtnl_trylock())
6010 		return restart_syscall();
6011 
6012 	*valp = val;
6013 
6014 	net = (struct net *)ctl->extra2;
6015 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6016 		rtnl_unlock();
6017 		return 0;
6018 	}
6019 
6020 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6021 		struct net_device *dev;
6022 
6023 		for_each_netdev(net, dev) {
6024 			idev = __in6_dev_get(dev);
6025 			if (idev)
6026 				addrconf_disable_policy_idev(idev, val);
6027 		}
6028 	} else {
6029 		idev = (struct inet6_dev *)ctl->extra1;
6030 		addrconf_disable_policy_idev(idev, val);
6031 	}
6032 
6033 	rtnl_unlock();
6034 	return 0;
6035 }
6036 
6037 static
6038 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6039 				   void __user *buffer, size_t *lenp,
6040 				   loff_t *ppos)
6041 {
6042 	int *valp = ctl->data;
6043 	int val = *valp;
6044 	loff_t pos = *ppos;
6045 	struct ctl_table lctl;
6046 	int ret;
6047 
6048 	lctl = *ctl;
6049 	lctl.data = &val;
6050 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6051 
6052 	if (write && (*valp != val))
6053 		ret = addrconf_disable_policy(ctl, valp, val);
6054 
6055 	if (ret)
6056 		*ppos = pos;
6057 
6058 	return ret;
6059 }
6060 
6061 static int minus_one = -1;
6062 static const int zero = 0;
6063 static const int one = 1;
6064 static const int two_five_five = 255;
6065 
6066 static const struct ctl_table addrconf_sysctl[] = {
6067 	{
6068 		.procname	= "forwarding",
6069 		.data		= &ipv6_devconf.forwarding,
6070 		.maxlen		= sizeof(int),
6071 		.mode		= 0644,
6072 		.proc_handler	= addrconf_sysctl_forward,
6073 	},
6074 	{
6075 		.procname	= "hop_limit",
6076 		.data		= &ipv6_devconf.hop_limit,
6077 		.maxlen		= sizeof(int),
6078 		.mode		= 0644,
6079 		.proc_handler	= proc_dointvec_minmax,
6080 		.extra1		= (void *)&one,
6081 		.extra2		= (void *)&two_five_five,
6082 	},
6083 	{
6084 		.procname	= "mtu",
6085 		.data		= &ipv6_devconf.mtu6,
6086 		.maxlen		= sizeof(int),
6087 		.mode		= 0644,
6088 		.proc_handler	= addrconf_sysctl_mtu,
6089 	},
6090 	{
6091 		.procname	= "accept_ra",
6092 		.data		= &ipv6_devconf.accept_ra,
6093 		.maxlen		= sizeof(int),
6094 		.mode		= 0644,
6095 		.proc_handler	= proc_dointvec,
6096 	},
6097 	{
6098 		.procname	= "accept_redirects",
6099 		.data		= &ipv6_devconf.accept_redirects,
6100 		.maxlen		= sizeof(int),
6101 		.mode		= 0644,
6102 		.proc_handler	= proc_dointvec,
6103 	},
6104 	{
6105 		.procname	= "autoconf",
6106 		.data		= &ipv6_devconf.autoconf,
6107 		.maxlen		= sizeof(int),
6108 		.mode		= 0644,
6109 		.proc_handler	= proc_dointvec,
6110 	},
6111 	{
6112 		.procname	= "dad_transmits",
6113 		.data		= &ipv6_devconf.dad_transmits,
6114 		.maxlen		= sizeof(int),
6115 		.mode		= 0644,
6116 		.proc_handler	= proc_dointvec,
6117 	},
6118 	{
6119 		.procname	= "router_solicitations",
6120 		.data		= &ipv6_devconf.rtr_solicits,
6121 		.maxlen		= sizeof(int),
6122 		.mode		= 0644,
6123 		.proc_handler	= proc_dointvec_minmax,
6124 		.extra1		= &minus_one,
6125 	},
6126 	{
6127 		.procname	= "router_solicitation_interval",
6128 		.data		= &ipv6_devconf.rtr_solicit_interval,
6129 		.maxlen		= sizeof(int),
6130 		.mode		= 0644,
6131 		.proc_handler	= proc_dointvec_jiffies,
6132 	},
6133 	{
6134 		.procname	= "router_solicitation_max_interval",
6135 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6136 		.maxlen		= sizeof(int),
6137 		.mode		= 0644,
6138 		.proc_handler	= proc_dointvec_jiffies,
6139 	},
6140 	{
6141 		.procname	= "router_solicitation_delay",
6142 		.data		= &ipv6_devconf.rtr_solicit_delay,
6143 		.maxlen		= sizeof(int),
6144 		.mode		= 0644,
6145 		.proc_handler	= proc_dointvec_jiffies,
6146 	},
6147 	{
6148 		.procname	= "force_mld_version",
6149 		.data		= &ipv6_devconf.force_mld_version,
6150 		.maxlen		= sizeof(int),
6151 		.mode		= 0644,
6152 		.proc_handler	= proc_dointvec,
6153 	},
6154 	{
6155 		.procname	= "mldv1_unsolicited_report_interval",
6156 		.data		=
6157 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6158 		.maxlen		= sizeof(int),
6159 		.mode		= 0644,
6160 		.proc_handler	= proc_dointvec_ms_jiffies,
6161 	},
6162 	{
6163 		.procname	= "mldv2_unsolicited_report_interval",
6164 		.data		=
6165 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6166 		.maxlen		= sizeof(int),
6167 		.mode		= 0644,
6168 		.proc_handler	= proc_dointvec_ms_jiffies,
6169 	},
6170 	{
6171 		.procname	= "use_tempaddr",
6172 		.data		= &ipv6_devconf.use_tempaddr,
6173 		.maxlen		= sizeof(int),
6174 		.mode		= 0644,
6175 		.proc_handler	= proc_dointvec,
6176 	},
6177 	{
6178 		.procname	= "temp_valid_lft",
6179 		.data		= &ipv6_devconf.temp_valid_lft,
6180 		.maxlen		= sizeof(int),
6181 		.mode		= 0644,
6182 		.proc_handler	= proc_dointvec,
6183 	},
6184 	{
6185 		.procname	= "temp_prefered_lft",
6186 		.data		= &ipv6_devconf.temp_prefered_lft,
6187 		.maxlen		= sizeof(int),
6188 		.mode		= 0644,
6189 		.proc_handler	= proc_dointvec,
6190 	},
6191 	{
6192 		.procname	= "regen_max_retry",
6193 		.data		= &ipv6_devconf.regen_max_retry,
6194 		.maxlen		= sizeof(int),
6195 		.mode		= 0644,
6196 		.proc_handler	= proc_dointvec,
6197 	},
6198 	{
6199 		.procname	= "max_desync_factor",
6200 		.data		= &ipv6_devconf.max_desync_factor,
6201 		.maxlen		= sizeof(int),
6202 		.mode		= 0644,
6203 		.proc_handler	= proc_dointvec,
6204 	},
6205 	{
6206 		.procname	= "max_addresses",
6207 		.data		= &ipv6_devconf.max_addresses,
6208 		.maxlen		= sizeof(int),
6209 		.mode		= 0644,
6210 		.proc_handler	= proc_dointvec,
6211 	},
6212 	{
6213 		.procname	= "accept_ra_defrtr",
6214 		.data		= &ipv6_devconf.accept_ra_defrtr,
6215 		.maxlen		= sizeof(int),
6216 		.mode		= 0644,
6217 		.proc_handler	= proc_dointvec,
6218 	},
6219 	{
6220 		.procname	= "accept_ra_min_hop_limit",
6221 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6222 		.maxlen		= sizeof(int),
6223 		.mode		= 0644,
6224 		.proc_handler	= proc_dointvec,
6225 	},
6226 	{
6227 		.procname	= "accept_ra_pinfo",
6228 		.data		= &ipv6_devconf.accept_ra_pinfo,
6229 		.maxlen		= sizeof(int),
6230 		.mode		= 0644,
6231 		.proc_handler	= proc_dointvec,
6232 	},
6233 #ifdef CONFIG_IPV6_ROUTER_PREF
6234 	{
6235 		.procname	= "accept_ra_rtr_pref",
6236 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6237 		.maxlen		= sizeof(int),
6238 		.mode		= 0644,
6239 		.proc_handler	= proc_dointvec,
6240 	},
6241 	{
6242 		.procname	= "router_probe_interval",
6243 		.data		= &ipv6_devconf.rtr_probe_interval,
6244 		.maxlen		= sizeof(int),
6245 		.mode		= 0644,
6246 		.proc_handler	= proc_dointvec_jiffies,
6247 	},
6248 #ifdef CONFIG_IPV6_ROUTE_INFO
6249 	{
6250 		.procname	= "accept_ra_rt_info_min_plen",
6251 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6252 		.maxlen		= sizeof(int),
6253 		.mode		= 0644,
6254 		.proc_handler	= proc_dointvec,
6255 	},
6256 	{
6257 		.procname	= "accept_ra_rt_info_max_plen",
6258 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6259 		.maxlen		= sizeof(int),
6260 		.mode		= 0644,
6261 		.proc_handler	= proc_dointvec,
6262 	},
6263 #endif
6264 #endif
6265 	{
6266 		.procname	= "proxy_ndp",
6267 		.data		= &ipv6_devconf.proxy_ndp,
6268 		.maxlen		= sizeof(int),
6269 		.mode		= 0644,
6270 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6271 	},
6272 	{
6273 		.procname	= "accept_source_route",
6274 		.data		= &ipv6_devconf.accept_source_route,
6275 		.maxlen		= sizeof(int),
6276 		.mode		= 0644,
6277 		.proc_handler	= proc_dointvec,
6278 	},
6279 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6280 	{
6281 		.procname	= "optimistic_dad",
6282 		.data		= &ipv6_devconf.optimistic_dad,
6283 		.maxlen		= sizeof(int),
6284 		.mode		= 0644,
6285 		.proc_handler   = proc_dointvec,
6286 	},
6287 	{
6288 		.procname	= "use_optimistic",
6289 		.data		= &ipv6_devconf.use_optimistic,
6290 		.maxlen		= sizeof(int),
6291 		.mode		= 0644,
6292 		.proc_handler	= proc_dointvec,
6293 	},
6294 #endif
6295 #ifdef CONFIG_IPV6_MROUTE
6296 	{
6297 		.procname	= "mc_forwarding",
6298 		.data		= &ipv6_devconf.mc_forwarding,
6299 		.maxlen		= sizeof(int),
6300 		.mode		= 0444,
6301 		.proc_handler	= proc_dointvec,
6302 	},
6303 #endif
6304 	{
6305 		.procname	= "disable_ipv6",
6306 		.data		= &ipv6_devconf.disable_ipv6,
6307 		.maxlen		= sizeof(int),
6308 		.mode		= 0644,
6309 		.proc_handler	= addrconf_sysctl_disable,
6310 	},
6311 	{
6312 		.procname	= "accept_dad",
6313 		.data		= &ipv6_devconf.accept_dad,
6314 		.maxlen		= sizeof(int),
6315 		.mode		= 0644,
6316 		.proc_handler	= proc_dointvec,
6317 	},
6318 	{
6319 		.procname	= "force_tllao",
6320 		.data		= &ipv6_devconf.force_tllao,
6321 		.maxlen		= sizeof(int),
6322 		.mode		= 0644,
6323 		.proc_handler	= proc_dointvec
6324 	},
6325 	{
6326 		.procname	= "ndisc_notify",
6327 		.data		= &ipv6_devconf.ndisc_notify,
6328 		.maxlen		= sizeof(int),
6329 		.mode		= 0644,
6330 		.proc_handler	= proc_dointvec
6331 	},
6332 	{
6333 		.procname	= "suppress_frag_ndisc",
6334 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6335 		.maxlen		= sizeof(int),
6336 		.mode		= 0644,
6337 		.proc_handler	= proc_dointvec
6338 	},
6339 	{
6340 		.procname	= "accept_ra_from_local",
6341 		.data		= &ipv6_devconf.accept_ra_from_local,
6342 		.maxlen		= sizeof(int),
6343 		.mode		= 0644,
6344 		.proc_handler	= proc_dointvec,
6345 	},
6346 	{
6347 		.procname	= "accept_ra_mtu",
6348 		.data		= &ipv6_devconf.accept_ra_mtu,
6349 		.maxlen		= sizeof(int),
6350 		.mode		= 0644,
6351 		.proc_handler	= proc_dointvec,
6352 	},
6353 	{
6354 		.procname	= "stable_secret",
6355 		.data		= &ipv6_devconf.stable_secret,
6356 		.maxlen		= IPV6_MAX_STRLEN,
6357 		.mode		= 0600,
6358 		.proc_handler	= addrconf_sysctl_stable_secret,
6359 	},
6360 	{
6361 		.procname	= "use_oif_addrs_only",
6362 		.data		= &ipv6_devconf.use_oif_addrs_only,
6363 		.maxlen		= sizeof(int),
6364 		.mode		= 0644,
6365 		.proc_handler	= proc_dointvec,
6366 	},
6367 	{
6368 		.procname	= "ignore_routes_with_linkdown",
6369 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6370 		.maxlen		= sizeof(int),
6371 		.mode		= 0644,
6372 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6373 	},
6374 	{
6375 		.procname	= "drop_unicast_in_l2_multicast",
6376 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6377 		.maxlen		= sizeof(int),
6378 		.mode		= 0644,
6379 		.proc_handler	= proc_dointvec,
6380 	},
6381 	{
6382 		.procname	= "drop_unsolicited_na",
6383 		.data		= &ipv6_devconf.drop_unsolicited_na,
6384 		.maxlen		= sizeof(int),
6385 		.mode		= 0644,
6386 		.proc_handler	= proc_dointvec,
6387 	},
6388 	{
6389 		.procname	= "keep_addr_on_down",
6390 		.data		= &ipv6_devconf.keep_addr_on_down,
6391 		.maxlen		= sizeof(int),
6392 		.mode		= 0644,
6393 		.proc_handler	= proc_dointvec,
6394 
6395 	},
6396 	{
6397 		.procname	= "seg6_enabled",
6398 		.data		= &ipv6_devconf.seg6_enabled,
6399 		.maxlen		= sizeof(int),
6400 		.mode		= 0644,
6401 		.proc_handler	= proc_dointvec,
6402 	},
6403 #ifdef CONFIG_IPV6_SEG6_HMAC
6404 	{
6405 		.procname	= "seg6_require_hmac",
6406 		.data		= &ipv6_devconf.seg6_require_hmac,
6407 		.maxlen		= sizeof(int),
6408 		.mode		= 0644,
6409 		.proc_handler	= proc_dointvec,
6410 	},
6411 #endif
6412 	{
6413 		.procname       = "enhanced_dad",
6414 		.data           = &ipv6_devconf.enhanced_dad,
6415 		.maxlen         = sizeof(int),
6416 		.mode           = 0644,
6417 		.proc_handler   = proc_dointvec,
6418 	},
6419 	{
6420 		.procname		= "addr_gen_mode",
6421 		.data			= &ipv6_devconf.addr_gen_mode,
6422 		.maxlen			= sizeof(int),
6423 		.mode			= 0644,
6424 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6425 	},
6426 	{
6427 		.procname       = "disable_policy",
6428 		.data           = &ipv6_devconf.disable_policy,
6429 		.maxlen         = sizeof(int),
6430 		.mode           = 0644,
6431 		.proc_handler   = addrconf_sysctl_disable_policy,
6432 	},
6433 	{
6434 		.procname	= "ndisc_tclass",
6435 		.data		= &ipv6_devconf.ndisc_tclass,
6436 		.maxlen		= sizeof(int),
6437 		.mode		= 0644,
6438 		.proc_handler	= proc_dointvec_minmax,
6439 		.extra1		= (void *)&zero,
6440 		.extra2		= (void *)&two_five_five,
6441 	},
6442 	{
6443 		/* sentinel */
6444 	}
6445 };
6446 
6447 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6448 		struct inet6_dev *idev, struct ipv6_devconf *p)
6449 {
6450 	int i, ifindex;
6451 	struct ctl_table *table;
6452 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6453 
6454 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6455 	if (!table)
6456 		goto out;
6457 
6458 	for (i = 0; table[i].data; i++) {
6459 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6460 		/* If one of these is already set, then it is not safe to
6461 		 * overwrite either of them: this makes proc_dointvec_minmax
6462 		 * usable.
6463 		 */
6464 		if (!table[i].extra1 && !table[i].extra2) {
6465 			table[i].extra1 = idev; /* embedded; no ref */
6466 			table[i].extra2 = net;
6467 		}
6468 	}
6469 
6470 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6471 
6472 	p->sysctl_header = register_net_sysctl(net, path, table);
6473 	if (!p->sysctl_header)
6474 		goto free;
6475 
6476 	if (!strcmp(dev_name, "all"))
6477 		ifindex = NETCONFA_IFINDEX_ALL;
6478 	else if (!strcmp(dev_name, "default"))
6479 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6480 	else
6481 		ifindex = idev->dev->ifindex;
6482 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6483 				     ifindex, p);
6484 	return 0;
6485 
6486 free:
6487 	kfree(table);
6488 out:
6489 	return -ENOBUFS;
6490 }
6491 
6492 static void __addrconf_sysctl_unregister(struct net *net,
6493 					 struct ipv6_devconf *p, int ifindex)
6494 {
6495 	struct ctl_table *table;
6496 
6497 	if (!p->sysctl_header)
6498 		return;
6499 
6500 	table = p->sysctl_header->ctl_table_arg;
6501 	unregister_net_sysctl_table(p->sysctl_header);
6502 	p->sysctl_header = NULL;
6503 	kfree(table);
6504 
6505 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6506 }
6507 
6508 static int addrconf_sysctl_register(struct inet6_dev *idev)
6509 {
6510 	int err;
6511 
6512 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6513 		return -EINVAL;
6514 
6515 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6516 				    &ndisc_ifinfo_sysctl_change);
6517 	if (err)
6518 		return err;
6519 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6520 					 idev, &idev->cnf);
6521 	if (err)
6522 		neigh_sysctl_unregister(idev->nd_parms);
6523 
6524 	return err;
6525 }
6526 
6527 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6528 {
6529 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6530 				     idev->dev->ifindex);
6531 	neigh_sysctl_unregister(idev->nd_parms);
6532 }
6533 
6534 
6535 #endif
6536 
6537 static int __net_init addrconf_init_net(struct net *net)
6538 {
6539 	int err = -ENOMEM;
6540 	struct ipv6_devconf *all, *dflt;
6541 
6542 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6543 	if (!all)
6544 		goto err_alloc_all;
6545 
6546 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6547 	if (!dflt)
6548 		goto err_alloc_dflt;
6549 
6550 	/* these will be inherited by all namespaces */
6551 	dflt->autoconf = ipv6_defaults.autoconf;
6552 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6553 
6554 	dflt->stable_secret.initialized = false;
6555 	all->stable_secret.initialized = false;
6556 
6557 	net->ipv6.devconf_all = all;
6558 	net->ipv6.devconf_dflt = dflt;
6559 
6560 #ifdef CONFIG_SYSCTL
6561 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6562 	if (err < 0)
6563 		goto err_reg_all;
6564 
6565 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6566 	if (err < 0)
6567 		goto err_reg_dflt;
6568 #endif
6569 	return 0;
6570 
6571 #ifdef CONFIG_SYSCTL
6572 err_reg_dflt:
6573 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6574 err_reg_all:
6575 	kfree(dflt);
6576 #endif
6577 err_alloc_dflt:
6578 	kfree(all);
6579 err_alloc_all:
6580 	return err;
6581 }
6582 
6583 static void __net_exit addrconf_exit_net(struct net *net)
6584 {
6585 #ifdef CONFIG_SYSCTL
6586 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6587 				     NETCONFA_IFINDEX_DEFAULT);
6588 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6589 				     NETCONFA_IFINDEX_ALL);
6590 #endif
6591 	kfree(net->ipv6.devconf_dflt);
6592 	kfree(net->ipv6.devconf_all);
6593 }
6594 
6595 static struct pernet_operations addrconf_ops = {
6596 	.init = addrconf_init_net,
6597 	.exit = addrconf_exit_net,
6598 };
6599 
6600 static struct rtnl_af_ops inet6_ops __read_mostly = {
6601 	.family		  = AF_INET6,
6602 	.fill_link_af	  = inet6_fill_link_af,
6603 	.get_link_af_size = inet6_get_link_af_size,
6604 	.validate_link_af = inet6_validate_link_af,
6605 	.set_link_af	  = inet6_set_link_af,
6606 };
6607 
6608 /*
6609  *	Init / cleanup code
6610  */
6611 
6612 int __init addrconf_init(void)
6613 {
6614 	struct inet6_dev *idev;
6615 	int i, err;
6616 
6617 	err = ipv6_addr_label_init();
6618 	if (err < 0) {
6619 		pr_crit("%s: cannot initialize default policy table: %d\n",
6620 			__func__, err);
6621 		goto out;
6622 	}
6623 
6624 	err = register_pernet_subsys(&addrconf_ops);
6625 	if (err < 0)
6626 		goto out_addrlabel;
6627 
6628 	addrconf_wq = create_workqueue("ipv6_addrconf");
6629 	if (!addrconf_wq) {
6630 		err = -ENOMEM;
6631 		goto out_nowq;
6632 	}
6633 
6634 	/* The addrconf netdev notifier requires that loopback_dev
6635 	 * has it's ipv6 private information allocated and setup
6636 	 * before it can bring up and give link-local addresses
6637 	 * to other devices which are up.
6638 	 *
6639 	 * Unfortunately, loopback_dev is not necessarily the first
6640 	 * entry in the global dev_base list of net devices.  In fact,
6641 	 * it is likely to be the very last entry on that list.
6642 	 * So this causes the notifier registry below to try and
6643 	 * give link-local addresses to all devices besides loopback_dev
6644 	 * first, then loopback_dev, which cases all the non-loopback_dev
6645 	 * devices to fail to get a link-local address.
6646 	 *
6647 	 * So, as a temporary fix, allocate the ipv6 structure for
6648 	 * loopback_dev first by hand.
6649 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6650 	 * device and it being up should be removed.
6651 	 */
6652 	rtnl_lock();
6653 	idev = ipv6_add_dev(init_net.loopback_dev);
6654 	rtnl_unlock();
6655 	if (IS_ERR(idev)) {
6656 		err = PTR_ERR(idev);
6657 		goto errlo;
6658 	}
6659 
6660 	ip6_route_init_special_entries();
6661 
6662 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6663 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6664 
6665 	register_netdevice_notifier(&ipv6_dev_notf);
6666 
6667 	addrconf_verify();
6668 
6669 	rtnl_af_register(&inet6_ops);
6670 
6671 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
6672 				   NULL, inet6_dump_ifinfo, 0);
6673 	if (err < 0)
6674 		goto errout;
6675 
6676 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
6677 				   inet6_rtm_newaddr, NULL, 0);
6678 	if (err < 0)
6679 		goto errout;
6680 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
6681 				   inet6_rtm_deladdr, NULL, 0);
6682 	if (err < 0)
6683 		goto errout;
6684 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
6685 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
6686 				   RTNL_FLAG_DOIT_UNLOCKED);
6687 	if (err < 0)
6688 		goto errout;
6689 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
6690 				   NULL, inet6_dump_ifmcaddr, 0);
6691 	if (err < 0)
6692 		goto errout;
6693 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
6694 				   NULL, inet6_dump_ifacaddr, 0);
6695 	if (err < 0)
6696 		goto errout;
6697 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
6698 				   inet6_netconf_get_devconf,
6699 				   inet6_netconf_dump_devconf,
6700 				   RTNL_FLAG_DOIT_UNLOCKED);
6701 	if (err < 0)
6702 		goto errout;
6703 	err = ipv6_addr_label_rtnl_register();
6704 	if (err < 0)
6705 		goto errout;
6706 
6707 	return 0;
6708 errout:
6709 	rtnl_unregister_all(PF_INET6);
6710 	rtnl_af_unregister(&inet6_ops);
6711 	unregister_netdevice_notifier(&ipv6_dev_notf);
6712 errlo:
6713 	destroy_workqueue(addrconf_wq);
6714 out_nowq:
6715 	unregister_pernet_subsys(&addrconf_ops);
6716 out_addrlabel:
6717 	ipv6_addr_label_cleanup();
6718 out:
6719 	return err;
6720 }
6721 
6722 void addrconf_cleanup(void)
6723 {
6724 	struct net_device *dev;
6725 	int i;
6726 
6727 	unregister_netdevice_notifier(&ipv6_dev_notf);
6728 	unregister_pernet_subsys(&addrconf_ops);
6729 	ipv6_addr_label_cleanup();
6730 
6731 	rtnl_af_unregister(&inet6_ops);
6732 
6733 	rtnl_lock();
6734 
6735 	/* clean dev list */
6736 	for_each_netdev(&init_net, dev) {
6737 		if (__in6_dev_get(dev) == NULL)
6738 			continue;
6739 		addrconf_ifdown(dev, 1);
6740 	}
6741 	addrconf_ifdown(init_net.loopback_dev, 2);
6742 
6743 	/*
6744 	 *	Check hash table.
6745 	 */
6746 	spin_lock_bh(&addrconf_hash_lock);
6747 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6748 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6749 	spin_unlock_bh(&addrconf_hash_lock);
6750 	cancel_delayed_work(&addr_chk_work);
6751 	rtnl_unlock();
6752 
6753 	destroy_workqueue(addrconf_wq);
6754 }
6755