xref: /linux/net/ipv6/addrconf.c (revision f84754dbc55e3abd8241e3038b615af65c745f47)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
139 
140 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
141 static int ipv6_count_addresses(const struct inet6_dev *idev);
142 static int ipv6_generate_stable_address(struct in6_addr *addr,
143 					u8 dad_count,
144 					const struct inet6_dev *idev);
145 
146 #define IN6_ADDR_HSIZE_SHIFT	8
147 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
148 /*
149  *	Configured unicast address hash table
150  */
151 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
152 static DEFINE_SPINLOCK(addrconf_hash_lock);
153 
154 static void addrconf_verify(void);
155 static void addrconf_verify_rtnl(void);
156 static void addrconf_verify_work(struct work_struct *);
157 
158 static struct workqueue_struct *addrconf_wq;
159 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
160 
161 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
162 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
163 
164 static void addrconf_type_change(struct net_device *dev,
165 				 unsigned long event);
166 static int addrconf_ifdown(struct net_device *dev, bool unregister);
167 
168 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
169 						  int plen,
170 						  const struct net_device *dev,
171 						  u32 flags, u32 noflags,
172 						  bool no_gw);
173 
174 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
175 static void addrconf_dad_work(struct work_struct *w);
176 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
177 				   bool send_na);
178 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
179 static void addrconf_rs_timer(struct timer_list *t);
180 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
181 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 
183 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
184 				struct prefix_info *pinfo);
185 
186 static struct ipv6_devconf ipv6_devconf __read_mostly = {
187 	.forwarding		= 0,
188 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
189 	.mtu6			= IPV6_MIN_MTU,
190 	.accept_ra		= 1,
191 	.accept_redirects	= 1,
192 	.autoconf		= 1,
193 	.force_mld_version	= 0,
194 	.mldv1_unsolicited_report_interval = 10 * HZ,
195 	.mldv2_unsolicited_report_interval = HZ,
196 	.dad_transmits		= 1,
197 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
198 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
199 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
200 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
201 	.use_tempaddr		= 0,
202 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
203 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
204 	.regen_max_retry	= REGEN_MAX_RETRY,
205 	.max_desync_factor	= MAX_DESYNC_FACTOR,
206 	.max_addresses		= IPV6_MAX_ADDRESSES,
207 	.accept_ra_defrtr	= 1,
208 	.accept_ra_from_local	= 0,
209 	.accept_ra_min_hop_limit= 1,
210 	.accept_ra_pinfo	= 1,
211 #ifdef CONFIG_IPV6_ROUTER_PREF
212 	.accept_ra_rtr_pref	= 1,
213 	.rtr_probe_interval	= 60 * HZ,
214 #ifdef CONFIG_IPV6_ROUTE_INFO
215 	.accept_ra_rt_info_min_plen = 0,
216 	.accept_ra_rt_info_max_plen = 0,
217 #endif
218 #endif
219 	.proxy_ndp		= 0,
220 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
221 	.disable_ipv6		= 0,
222 	.accept_dad		= 0,
223 	.suppress_frag_ndisc	= 1,
224 	.accept_ra_mtu		= 1,
225 	.stable_secret		= {
226 		.initialized = false,
227 	},
228 	.use_oif_addrs_only	= 0,
229 	.ignore_routes_with_linkdown = 0,
230 	.keep_addr_on_down	= 0,
231 	.seg6_enabled		= 0,
232 #ifdef CONFIG_IPV6_SEG6_HMAC
233 	.seg6_require_hmac	= 0,
234 #endif
235 	.enhanced_dad           = 1,
236 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
237 	.disable_policy		= 0,
238 	.rpl_seg_enabled	= 0,
239 };
240 
241 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
242 	.forwarding		= 0,
243 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
244 	.mtu6			= IPV6_MIN_MTU,
245 	.accept_ra		= 1,
246 	.accept_redirects	= 1,
247 	.autoconf		= 1,
248 	.force_mld_version	= 0,
249 	.mldv1_unsolicited_report_interval = 10 * HZ,
250 	.mldv2_unsolicited_report_interval = HZ,
251 	.dad_transmits		= 1,
252 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
253 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
254 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
255 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
256 	.use_tempaddr		= 0,
257 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
258 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
259 	.regen_max_retry	= REGEN_MAX_RETRY,
260 	.max_desync_factor	= MAX_DESYNC_FACTOR,
261 	.max_addresses		= IPV6_MAX_ADDRESSES,
262 	.accept_ra_defrtr	= 1,
263 	.accept_ra_from_local	= 0,
264 	.accept_ra_min_hop_limit= 1,
265 	.accept_ra_pinfo	= 1,
266 #ifdef CONFIG_IPV6_ROUTER_PREF
267 	.accept_ra_rtr_pref	= 1,
268 	.rtr_probe_interval	= 60 * HZ,
269 #ifdef CONFIG_IPV6_ROUTE_INFO
270 	.accept_ra_rt_info_min_plen = 0,
271 	.accept_ra_rt_info_max_plen = 0,
272 #endif
273 #endif
274 	.proxy_ndp		= 0,
275 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
276 	.disable_ipv6		= 0,
277 	.accept_dad		= 1,
278 	.suppress_frag_ndisc	= 1,
279 	.accept_ra_mtu		= 1,
280 	.stable_secret		= {
281 		.initialized = false,
282 	},
283 	.use_oif_addrs_only	= 0,
284 	.ignore_routes_with_linkdown = 0,
285 	.keep_addr_on_down	= 0,
286 	.seg6_enabled		= 0,
287 #ifdef CONFIG_IPV6_SEG6_HMAC
288 	.seg6_require_hmac	= 0,
289 #endif
290 	.enhanced_dad           = 1,
291 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
292 	.disable_policy		= 0,
293 	.rpl_seg_enabled	= 0,
294 };
295 
296 /* Check if link is ready: is it up and is a valid qdisc available */
297 static inline bool addrconf_link_ready(const struct net_device *dev)
298 {
299 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
300 }
301 
302 static void addrconf_del_rs_timer(struct inet6_dev *idev)
303 {
304 	if (del_timer(&idev->rs_timer))
305 		__in6_dev_put(idev);
306 }
307 
308 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
309 {
310 	if (cancel_delayed_work(&ifp->dad_work))
311 		__in6_ifa_put(ifp);
312 }
313 
314 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
315 				  unsigned long when)
316 {
317 	if (!timer_pending(&idev->rs_timer))
318 		in6_dev_hold(idev);
319 	mod_timer(&idev->rs_timer, jiffies + when);
320 }
321 
322 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
323 				   unsigned long delay)
324 {
325 	in6_ifa_hold(ifp);
326 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
327 		in6_ifa_put(ifp);
328 }
329 
330 static int snmp6_alloc_dev(struct inet6_dev *idev)
331 {
332 	int i;
333 
334 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
335 	if (!idev->stats.ipv6)
336 		goto err_ip;
337 
338 	for_each_possible_cpu(i) {
339 		struct ipstats_mib *addrconf_stats;
340 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
341 		u64_stats_init(&addrconf_stats->syncp);
342 	}
343 
344 
345 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
346 					GFP_KERNEL);
347 	if (!idev->stats.icmpv6dev)
348 		goto err_icmp;
349 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
350 					   GFP_KERNEL);
351 	if (!idev->stats.icmpv6msgdev)
352 		goto err_icmpmsg;
353 
354 	return 0;
355 
356 err_icmpmsg:
357 	kfree(idev->stats.icmpv6dev);
358 err_icmp:
359 	free_percpu(idev->stats.ipv6);
360 err_ip:
361 	return -ENOMEM;
362 }
363 
364 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
365 {
366 	struct inet6_dev *ndev;
367 	int err = -ENOMEM;
368 
369 	ASSERT_RTNL();
370 
371 	if (dev->mtu < IPV6_MIN_MTU)
372 		return ERR_PTR(-EINVAL);
373 
374 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
375 	if (!ndev)
376 		return ERR_PTR(err);
377 
378 	rwlock_init(&ndev->lock);
379 	ndev->dev = dev;
380 	INIT_LIST_HEAD(&ndev->addr_list);
381 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
382 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
383 
384 	if (ndev->cnf.stable_secret.initialized)
385 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
386 
387 	ndev->cnf.mtu6 = dev->mtu;
388 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
389 	if (!ndev->nd_parms) {
390 		kfree(ndev);
391 		return ERR_PTR(err);
392 	}
393 	if (ndev->cnf.forwarding)
394 		dev_disable_lro(dev);
395 	/* We refer to the device */
396 	dev_hold(dev);
397 
398 	if (snmp6_alloc_dev(ndev) < 0) {
399 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
400 			   __func__);
401 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
402 		dev_put(dev);
403 		kfree(ndev);
404 		return ERR_PTR(err);
405 	}
406 
407 	if (snmp6_register_dev(ndev) < 0) {
408 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
409 			   __func__, dev->name);
410 		goto err_release;
411 	}
412 
413 	/* One reference from device. */
414 	refcount_set(&ndev->refcnt, 1);
415 
416 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
417 		ndev->cnf.accept_dad = -1;
418 
419 #if IS_ENABLED(CONFIG_IPV6_SIT)
420 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
421 		pr_info("%s: Disabled Multicast RS\n", dev->name);
422 		ndev->cnf.rtr_solicits = 0;
423 	}
424 #endif
425 
426 	INIT_LIST_HEAD(&ndev->tempaddr_list);
427 	ndev->desync_factor = U32_MAX;
428 	if ((dev->flags&IFF_LOOPBACK) ||
429 	    dev->type == ARPHRD_TUNNEL ||
430 	    dev->type == ARPHRD_TUNNEL6 ||
431 	    dev->type == ARPHRD_SIT ||
432 	    dev->type == ARPHRD_NONE) {
433 		ndev->cnf.use_tempaddr = -1;
434 	}
435 
436 	ndev->token = in6addr_any;
437 
438 	if (netif_running(dev) && addrconf_link_ready(dev))
439 		ndev->if_flags |= IF_READY;
440 
441 	ipv6_mc_init_dev(ndev);
442 	ndev->tstamp = jiffies;
443 	err = addrconf_sysctl_register(ndev);
444 	if (err) {
445 		ipv6_mc_destroy_dev(ndev);
446 		snmp6_unregister_dev(ndev);
447 		goto err_release;
448 	}
449 	/* protected by rtnl_lock */
450 	rcu_assign_pointer(dev->ip6_ptr, ndev);
451 
452 	/* Join interface-local all-node multicast group */
453 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
454 
455 	/* Join all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
457 
458 	/* Join all-router multicast group if forwarding is set */
459 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
460 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
461 
462 	return ndev;
463 
464 err_release:
465 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
466 	ndev->dead = 1;
467 	in6_dev_finish_destroy(ndev);
468 	return ERR_PTR(err);
469 }
470 
471 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
472 {
473 	struct inet6_dev *idev;
474 
475 	ASSERT_RTNL();
476 
477 	idev = __in6_dev_get(dev);
478 	if (!idev) {
479 		idev = ipv6_add_dev(dev);
480 		if (IS_ERR(idev))
481 			return idev;
482 	}
483 
484 	if (dev->flags&IFF_UP)
485 		ipv6_mc_up(idev);
486 	return idev;
487 }
488 
489 static int inet6_netconf_msgsize_devconf(int type)
490 {
491 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
492 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
493 	bool all = false;
494 
495 	if (type == NETCONFA_ALL)
496 		all = true;
497 
498 	if (all || type == NETCONFA_FORWARDING)
499 		size += nla_total_size(4);
500 #ifdef CONFIG_IPV6_MROUTE
501 	if (all || type == NETCONFA_MC_FORWARDING)
502 		size += nla_total_size(4);
503 #endif
504 	if (all || type == NETCONFA_PROXY_NEIGH)
505 		size += nla_total_size(4);
506 
507 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
508 		size += nla_total_size(4);
509 
510 	return size;
511 }
512 
513 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
514 				      struct ipv6_devconf *devconf, u32 portid,
515 				      u32 seq, int event, unsigned int flags,
516 				      int type)
517 {
518 	struct nlmsghdr  *nlh;
519 	struct netconfmsg *ncm;
520 	bool all = false;
521 
522 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
523 			flags);
524 	if (!nlh)
525 		return -EMSGSIZE;
526 
527 	if (type == NETCONFA_ALL)
528 		all = true;
529 
530 	ncm = nlmsg_data(nlh);
531 	ncm->ncm_family = AF_INET6;
532 
533 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
534 		goto nla_put_failure;
535 
536 	if (!devconf)
537 		goto out;
538 
539 	if ((all || type == NETCONFA_FORWARDING) &&
540 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
541 		goto nla_put_failure;
542 #ifdef CONFIG_IPV6_MROUTE
543 	if ((all || type == NETCONFA_MC_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
545 			devconf->mc_forwarding) < 0)
546 		goto nla_put_failure;
547 #endif
548 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
549 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
550 		goto nla_put_failure;
551 
552 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
553 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
554 			devconf->ignore_routes_with_linkdown) < 0)
555 		goto nla_put_failure;
556 
557 out:
558 	nlmsg_end(skb, nlh);
559 	return 0;
560 
561 nla_put_failure:
562 	nlmsg_cancel(skb, nlh);
563 	return -EMSGSIZE;
564 }
565 
566 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
567 				  int ifindex, struct ipv6_devconf *devconf)
568 {
569 	struct sk_buff *skb;
570 	int err = -ENOBUFS;
571 
572 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
573 	if (!skb)
574 		goto errout;
575 
576 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
577 					 event, 0, type);
578 	if (err < 0) {
579 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
580 		WARN_ON(err == -EMSGSIZE);
581 		kfree_skb(skb);
582 		goto errout;
583 	}
584 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
585 	return;
586 errout:
587 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
588 }
589 
590 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
591 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
592 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
593 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
594 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
595 };
596 
597 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
598 				       const struct nlmsghdr *nlh,
599 				       struct nlattr **tb,
600 				       struct netlink_ext_ack *extack)
601 {
602 	int i, err;
603 
604 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
605 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
606 		return -EINVAL;
607 	}
608 
609 	if (!netlink_strict_get_check(skb))
610 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
611 					      tb, NETCONFA_MAX,
612 					      devconf_ipv6_policy, extack);
613 
614 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
615 					    tb, NETCONFA_MAX,
616 					    devconf_ipv6_policy, extack);
617 	if (err)
618 		return err;
619 
620 	for (i = 0; i <= NETCONFA_MAX; i++) {
621 		if (!tb[i])
622 			continue;
623 
624 		switch (i) {
625 		case NETCONFA_IFINDEX:
626 			break;
627 		default:
628 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
629 			return -EINVAL;
630 		}
631 	}
632 
633 	return 0;
634 }
635 
636 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
637 				     struct nlmsghdr *nlh,
638 				     struct netlink_ext_ack *extack)
639 {
640 	struct net *net = sock_net(in_skb->sk);
641 	struct nlattr *tb[NETCONFA_MAX+1];
642 	struct inet6_dev *in6_dev = NULL;
643 	struct net_device *dev = NULL;
644 	struct sk_buff *skb;
645 	struct ipv6_devconf *devconf;
646 	int ifindex;
647 	int err;
648 
649 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
650 	if (err < 0)
651 		return err;
652 
653 	if (!tb[NETCONFA_IFINDEX])
654 		return -EINVAL;
655 
656 	err = -EINVAL;
657 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
658 	switch (ifindex) {
659 	case NETCONFA_IFINDEX_ALL:
660 		devconf = net->ipv6.devconf_all;
661 		break;
662 	case NETCONFA_IFINDEX_DEFAULT:
663 		devconf = net->ipv6.devconf_dflt;
664 		break;
665 	default:
666 		dev = dev_get_by_index(net, ifindex);
667 		if (!dev)
668 			return -EINVAL;
669 		in6_dev = in6_dev_get(dev);
670 		if (!in6_dev)
671 			goto errout;
672 		devconf = &in6_dev->cnf;
673 		break;
674 	}
675 
676 	err = -ENOBUFS;
677 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
678 	if (!skb)
679 		goto errout;
680 
681 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
682 					 NETLINK_CB(in_skb).portid,
683 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
684 					 NETCONFA_ALL);
685 	if (err < 0) {
686 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
687 		WARN_ON(err == -EMSGSIZE);
688 		kfree_skb(skb);
689 		goto errout;
690 	}
691 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
692 errout:
693 	if (in6_dev)
694 		in6_dev_put(in6_dev);
695 	if (dev)
696 		dev_put(dev);
697 	return err;
698 }
699 
700 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
701 				      struct netlink_callback *cb)
702 {
703 	const struct nlmsghdr *nlh = cb->nlh;
704 	struct net *net = sock_net(skb->sk);
705 	int h, s_h;
706 	int idx, s_idx;
707 	struct net_device *dev;
708 	struct inet6_dev *idev;
709 	struct hlist_head *head;
710 
711 	if (cb->strict_check) {
712 		struct netlink_ext_ack *extack = cb->extack;
713 		struct netconfmsg *ncm;
714 
715 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
716 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
717 			return -EINVAL;
718 		}
719 
720 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
721 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
722 			return -EINVAL;
723 		}
724 	}
725 
726 	s_h = cb->args[0];
727 	s_idx = idx = cb->args[1];
728 
729 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
730 		idx = 0;
731 		head = &net->dev_index_head[h];
732 		rcu_read_lock();
733 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
734 			  net->dev_base_seq;
735 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
736 			if (idx < s_idx)
737 				goto cont;
738 			idev = __in6_dev_get(dev);
739 			if (!idev)
740 				goto cont;
741 
742 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
743 						       &idev->cnf,
744 						       NETLINK_CB(cb->skb).portid,
745 						       nlh->nlmsg_seq,
746 						       RTM_NEWNETCONF,
747 						       NLM_F_MULTI,
748 						       NETCONFA_ALL) < 0) {
749 				rcu_read_unlock();
750 				goto done;
751 			}
752 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
753 cont:
754 			idx++;
755 		}
756 		rcu_read_unlock();
757 	}
758 	if (h == NETDEV_HASHENTRIES) {
759 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
760 					       net->ipv6.devconf_all,
761 					       NETLINK_CB(cb->skb).portid,
762 					       nlh->nlmsg_seq,
763 					       RTM_NEWNETCONF, NLM_F_MULTI,
764 					       NETCONFA_ALL) < 0)
765 			goto done;
766 		else
767 			h++;
768 	}
769 	if (h == NETDEV_HASHENTRIES + 1) {
770 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
771 					       net->ipv6.devconf_dflt,
772 					       NETLINK_CB(cb->skb).portid,
773 					       nlh->nlmsg_seq,
774 					       RTM_NEWNETCONF, NLM_F_MULTI,
775 					       NETCONFA_ALL) < 0)
776 			goto done;
777 		else
778 			h++;
779 	}
780 done:
781 	cb->args[0] = h;
782 	cb->args[1] = idx;
783 
784 	return skb->len;
785 }
786 
787 #ifdef CONFIG_SYSCTL
788 static void dev_forward_change(struct inet6_dev *idev)
789 {
790 	struct net_device *dev;
791 	struct inet6_ifaddr *ifa;
792 
793 	if (!idev)
794 		return;
795 	dev = idev->dev;
796 	if (idev->cnf.forwarding)
797 		dev_disable_lro(dev);
798 	if (dev->flags & IFF_MULTICAST) {
799 		if (idev->cnf.forwarding) {
800 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
801 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
802 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
803 		} else {
804 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
805 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
806 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
807 		}
808 	}
809 
810 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
811 		if (ifa->flags&IFA_F_TENTATIVE)
812 			continue;
813 		if (idev->cnf.forwarding)
814 			addrconf_join_anycast(ifa);
815 		else
816 			addrconf_leave_anycast(ifa);
817 	}
818 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
819 				     NETCONFA_FORWARDING,
820 				     dev->ifindex, &idev->cnf);
821 }
822 
823 
824 static void addrconf_forward_change(struct net *net, __s32 newf)
825 {
826 	struct net_device *dev;
827 	struct inet6_dev *idev;
828 
829 	for_each_netdev(net, dev) {
830 		idev = __in6_dev_get(dev);
831 		if (idev) {
832 			int changed = (!idev->cnf.forwarding) ^ (!newf);
833 			idev->cnf.forwarding = newf;
834 			if (changed)
835 				dev_forward_change(idev);
836 		}
837 	}
838 }
839 
840 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
841 {
842 	struct net *net;
843 	int old;
844 
845 	if (!rtnl_trylock())
846 		return restart_syscall();
847 
848 	net = (struct net *)table->extra2;
849 	old = *p;
850 	*p = newf;
851 
852 	if (p == &net->ipv6.devconf_dflt->forwarding) {
853 		if ((!newf) ^ (!old))
854 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
855 						     NETCONFA_FORWARDING,
856 						     NETCONFA_IFINDEX_DEFAULT,
857 						     net->ipv6.devconf_dflt);
858 		rtnl_unlock();
859 		return 0;
860 	}
861 
862 	if (p == &net->ipv6.devconf_all->forwarding) {
863 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
864 
865 		net->ipv6.devconf_dflt->forwarding = newf;
866 		if ((!newf) ^ (!old_dflt))
867 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
868 						     NETCONFA_FORWARDING,
869 						     NETCONFA_IFINDEX_DEFAULT,
870 						     net->ipv6.devconf_dflt);
871 
872 		addrconf_forward_change(net, newf);
873 		if ((!newf) ^ (!old))
874 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
875 						     NETCONFA_FORWARDING,
876 						     NETCONFA_IFINDEX_ALL,
877 						     net->ipv6.devconf_all);
878 	} else if ((!newf) ^ (!old))
879 		dev_forward_change((struct inet6_dev *)table->extra1);
880 	rtnl_unlock();
881 
882 	if (newf)
883 		rt6_purge_dflt_routers(net);
884 	return 1;
885 }
886 
887 static void addrconf_linkdown_change(struct net *net, __s32 newf)
888 {
889 	struct net_device *dev;
890 	struct inet6_dev *idev;
891 
892 	for_each_netdev(net, dev) {
893 		idev = __in6_dev_get(dev);
894 		if (idev) {
895 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
896 
897 			idev->cnf.ignore_routes_with_linkdown = newf;
898 			if (changed)
899 				inet6_netconf_notify_devconf(dev_net(dev),
900 							     RTM_NEWNETCONF,
901 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
902 							     dev->ifindex,
903 							     &idev->cnf);
904 		}
905 	}
906 }
907 
908 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
909 {
910 	struct net *net;
911 	int old;
912 
913 	if (!rtnl_trylock())
914 		return restart_syscall();
915 
916 	net = (struct net *)table->extra2;
917 	old = *p;
918 	*p = newf;
919 
920 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
921 		if ((!newf) ^ (!old))
922 			inet6_netconf_notify_devconf(net,
923 						     RTM_NEWNETCONF,
924 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
925 						     NETCONFA_IFINDEX_DEFAULT,
926 						     net->ipv6.devconf_dflt);
927 		rtnl_unlock();
928 		return 0;
929 	}
930 
931 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
932 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
933 		addrconf_linkdown_change(net, newf);
934 		if ((!newf) ^ (!old))
935 			inet6_netconf_notify_devconf(net,
936 						     RTM_NEWNETCONF,
937 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
938 						     NETCONFA_IFINDEX_ALL,
939 						     net->ipv6.devconf_all);
940 	}
941 	rtnl_unlock();
942 
943 	return 1;
944 }
945 
946 #endif
947 
948 /* Nobody refers to this ifaddr, destroy it */
949 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
950 {
951 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
952 
953 #ifdef NET_REFCNT_DEBUG
954 	pr_debug("%s\n", __func__);
955 #endif
956 
957 	in6_dev_put(ifp->idev);
958 
959 	if (cancel_delayed_work(&ifp->dad_work))
960 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
961 			  ifp);
962 
963 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
964 		pr_warn("Freeing alive inet6 address %p\n", ifp);
965 		return;
966 	}
967 
968 	kfree_rcu(ifp, rcu);
969 }
970 
971 static void
972 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
973 {
974 	struct list_head *p;
975 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
976 
977 	/*
978 	 * Each device address list is sorted in order of scope -
979 	 * global before linklocal.
980 	 */
981 	list_for_each(p, &idev->addr_list) {
982 		struct inet6_ifaddr *ifa
983 			= list_entry(p, struct inet6_ifaddr, if_list);
984 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
985 			break;
986 	}
987 
988 	list_add_tail_rcu(&ifp->if_list, p);
989 }
990 
991 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
992 {
993 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
994 
995 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
996 }
997 
998 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
999 			       struct net_device *dev, unsigned int hash)
1000 {
1001 	struct inet6_ifaddr *ifp;
1002 
1003 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1004 		if (!net_eq(dev_net(ifp->idev->dev), net))
1005 			continue;
1006 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1007 			if (!dev || ifp->idev->dev == dev)
1008 				return true;
1009 		}
1010 	}
1011 	return false;
1012 }
1013 
1014 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1015 {
1016 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1017 	int err = 0;
1018 
1019 	spin_lock(&addrconf_hash_lock);
1020 
1021 	/* Ignore adding duplicate addresses on an interface */
1022 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1023 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1024 		err = -EEXIST;
1025 	} else {
1026 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1027 	}
1028 
1029 	spin_unlock(&addrconf_hash_lock);
1030 
1031 	return err;
1032 }
1033 
1034 /* On success it returns ifp with increased reference count */
1035 
1036 static struct inet6_ifaddr *
1037 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1038 	      bool can_block, struct netlink_ext_ack *extack)
1039 {
1040 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1041 	int addr_type = ipv6_addr_type(cfg->pfx);
1042 	struct net *net = dev_net(idev->dev);
1043 	struct inet6_ifaddr *ifa = NULL;
1044 	struct fib6_info *f6i = NULL;
1045 	int err = 0;
1046 
1047 	if (addr_type == IPV6_ADDR_ANY ||
1048 	    (addr_type & IPV6_ADDR_MULTICAST &&
1049 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1050 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1051 	     !netif_is_l3_master(idev->dev) &&
1052 	     addr_type & IPV6_ADDR_LOOPBACK))
1053 		return ERR_PTR(-EADDRNOTAVAIL);
1054 
1055 	if (idev->dead) {
1056 		err = -ENODEV;			/*XXX*/
1057 		goto out;
1058 	}
1059 
1060 	if (idev->cnf.disable_ipv6) {
1061 		err = -EACCES;
1062 		goto out;
1063 	}
1064 
1065 	/* validator notifier needs to be blocking;
1066 	 * do not call in atomic context
1067 	 */
1068 	if (can_block) {
1069 		struct in6_validator_info i6vi = {
1070 			.i6vi_addr = *cfg->pfx,
1071 			.i6vi_dev = idev,
1072 			.extack = extack,
1073 		};
1074 
1075 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1076 		err = notifier_to_errno(err);
1077 		if (err < 0)
1078 			goto out;
1079 	}
1080 
1081 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1082 	if (!ifa) {
1083 		err = -ENOBUFS;
1084 		goto out;
1085 	}
1086 
1087 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1088 	if (IS_ERR(f6i)) {
1089 		err = PTR_ERR(f6i);
1090 		f6i = NULL;
1091 		goto out;
1092 	}
1093 
1094 	if (net->ipv6.devconf_all->disable_policy ||
1095 	    idev->cnf.disable_policy)
1096 		f6i->dst_nopolicy = true;
1097 
1098 	neigh_parms_data_state_setall(idev->nd_parms);
1099 
1100 	ifa->addr = *cfg->pfx;
1101 	if (cfg->peer_pfx)
1102 		ifa->peer_addr = *cfg->peer_pfx;
1103 
1104 	spin_lock_init(&ifa->lock);
1105 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1106 	INIT_HLIST_NODE(&ifa->addr_lst);
1107 	ifa->scope = cfg->scope;
1108 	ifa->prefix_len = cfg->plen;
1109 	ifa->rt_priority = cfg->rt_priority;
1110 	ifa->flags = cfg->ifa_flags;
1111 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1112 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1113 		ifa->flags |= IFA_F_TENTATIVE;
1114 	ifa->valid_lft = cfg->valid_lft;
1115 	ifa->prefered_lft = cfg->preferred_lft;
1116 	ifa->cstamp = ifa->tstamp = jiffies;
1117 	ifa->tokenized = false;
1118 
1119 	ifa->rt = f6i;
1120 
1121 	ifa->idev = idev;
1122 	in6_dev_hold(idev);
1123 
1124 	/* For caller */
1125 	refcount_set(&ifa->refcnt, 1);
1126 
1127 	rcu_read_lock_bh();
1128 
1129 	err = ipv6_add_addr_hash(idev->dev, ifa);
1130 	if (err < 0) {
1131 		rcu_read_unlock_bh();
1132 		goto out;
1133 	}
1134 
1135 	write_lock(&idev->lock);
1136 
1137 	/* Add to inet6_dev unicast addr list. */
1138 	ipv6_link_dev_addr(idev, ifa);
1139 
1140 	if (ifa->flags&IFA_F_TEMPORARY) {
1141 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1142 		in6_ifa_hold(ifa);
1143 	}
1144 
1145 	in6_ifa_hold(ifa);
1146 	write_unlock(&idev->lock);
1147 
1148 	rcu_read_unlock_bh();
1149 
1150 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1151 out:
1152 	if (unlikely(err < 0)) {
1153 		fib6_info_release(f6i);
1154 
1155 		if (ifa) {
1156 			if (ifa->idev)
1157 				in6_dev_put(ifa->idev);
1158 			kfree(ifa);
1159 		}
1160 		ifa = ERR_PTR(err);
1161 	}
1162 
1163 	return ifa;
1164 }
1165 
1166 enum cleanup_prefix_rt_t {
1167 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1168 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1169 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1170 };
1171 
1172 /*
1173  * Check, whether the prefix for ifp would still need a prefix route
1174  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1175  * constants.
1176  *
1177  * 1) we don't purge prefix if address was not permanent.
1178  *    prefix is managed by its own lifetime.
1179  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1180  * 3) if there are no addresses, delete prefix.
1181  * 4) if there are still other permanent address(es),
1182  *    corresponding prefix is still permanent.
1183  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1184  *    don't purge the prefix, assume user space is managing it.
1185  * 6) otherwise, update prefix lifetime to the
1186  *    longest valid lifetime among the corresponding
1187  *    addresses on the device.
1188  *    Note: subsequent RA will update lifetime.
1189  **/
1190 static enum cleanup_prefix_rt_t
1191 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1192 {
1193 	struct inet6_ifaddr *ifa;
1194 	struct inet6_dev *idev = ifp->idev;
1195 	unsigned long lifetime;
1196 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1197 
1198 	*expires = jiffies;
1199 
1200 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1201 		if (ifa == ifp)
1202 			continue;
1203 		if (ifa->prefix_len != ifp->prefix_len ||
1204 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1205 				       ifp->prefix_len))
1206 			continue;
1207 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1208 			return CLEANUP_PREFIX_RT_NOP;
1209 
1210 		action = CLEANUP_PREFIX_RT_EXPIRE;
1211 
1212 		spin_lock(&ifa->lock);
1213 
1214 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1215 		/*
1216 		 * Note: Because this address is
1217 		 * not permanent, lifetime <
1218 		 * LONG_MAX / HZ here.
1219 		 */
1220 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1221 			*expires = ifa->tstamp + lifetime * HZ;
1222 		spin_unlock(&ifa->lock);
1223 	}
1224 
1225 	return action;
1226 }
1227 
1228 static void
1229 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1230 		     bool del_rt, bool del_peer)
1231 {
1232 	struct fib6_info *f6i;
1233 
1234 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1235 					ifp->prefix_len,
1236 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1237 	if (f6i) {
1238 		if (del_rt)
1239 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1240 		else {
1241 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1242 				fib6_set_expires(f6i, expires);
1243 			fib6_info_release(f6i);
1244 		}
1245 	}
1246 }
1247 
1248 
1249 /* This function wants to get referenced ifp and releases it before return */
1250 
1251 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1252 {
1253 	int state;
1254 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1255 	unsigned long expires;
1256 
1257 	ASSERT_RTNL();
1258 
1259 	spin_lock_bh(&ifp->lock);
1260 	state = ifp->state;
1261 	ifp->state = INET6_IFADDR_STATE_DEAD;
1262 	spin_unlock_bh(&ifp->lock);
1263 
1264 	if (state == INET6_IFADDR_STATE_DEAD)
1265 		goto out;
1266 
1267 	spin_lock_bh(&addrconf_hash_lock);
1268 	hlist_del_init_rcu(&ifp->addr_lst);
1269 	spin_unlock_bh(&addrconf_hash_lock);
1270 
1271 	write_lock_bh(&ifp->idev->lock);
1272 
1273 	if (ifp->flags&IFA_F_TEMPORARY) {
1274 		list_del(&ifp->tmp_list);
1275 		if (ifp->ifpub) {
1276 			in6_ifa_put(ifp->ifpub);
1277 			ifp->ifpub = NULL;
1278 		}
1279 		__in6_ifa_put(ifp);
1280 	}
1281 
1282 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1283 		action = check_cleanup_prefix_route(ifp, &expires);
1284 
1285 	list_del_rcu(&ifp->if_list);
1286 	__in6_ifa_put(ifp);
1287 
1288 	write_unlock_bh(&ifp->idev->lock);
1289 
1290 	addrconf_del_dad_work(ifp);
1291 
1292 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1293 
1294 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1295 
1296 	if (action != CLEANUP_PREFIX_RT_NOP) {
1297 		cleanup_prefix_route(ifp, expires,
1298 			action == CLEANUP_PREFIX_RT_DEL, false);
1299 	}
1300 
1301 	/* clean up prefsrc entries */
1302 	rt6_remove_prefsrc(ifp);
1303 out:
1304 	in6_ifa_put(ifp);
1305 }
1306 
1307 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1308 {
1309 	struct inet6_dev *idev = ifp->idev;
1310 	unsigned long tmp_tstamp, age;
1311 	unsigned long regen_advance;
1312 	unsigned long now = jiffies;
1313 	s32 cnf_temp_preferred_lft;
1314 	struct inet6_ifaddr *ift;
1315 	struct ifa6_config cfg;
1316 	long max_desync_factor;
1317 	struct in6_addr addr;
1318 	int ret = 0;
1319 
1320 	write_lock_bh(&idev->lock);
1321 
1322 retry:
1323 	in6_dev_hold(idev);
1324 	if (idev->cnf.use_tempaddr <= 0) {
1325 		write_unlock_bh(&idev->lock);
1326 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1327 		in6_dev_put(idev);
1328 		ret = -1;
1329 		goto out;
1330 	}
1331 	spin_lock_bh(&ifp->lock);
1332 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1333 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1334 		spin_unlock_bh(&ifp->lock);
1335 		write_unlock_bh(&idev->lock);
1336 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1337 			__func__);
1338 		in6_dev_put(idev);
1339 		ret = -1;
1340 		goto out;
1341 	}
1342 	in6_ifa_hold(ifp);
1343 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1344 	ipv6_gen_rnd_iid(&addr);
1345 
1346 	age = (now - ifp->tstamp) / HZ;
1347 
1348 	regen_advance = idev->cnf.regen_max_retry *
1349 			idev->cnf.dad_transmits *
1350 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1351 
1352 	/* recalculate max_desync_factor each time and update
1353 	 * idev->desync_factor if it's larger
1354 	 */
1355 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1356 	max_desync_factor = min_t(__u32,
1357 				  idev->cnf.max_desync_factor,
1358 				  cnf_temp_preferred_lft - regen_advance);
1359 
1360 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1361 		if (max_desync_factor > 0) {
1362 			get_random_bytes(&idev->desync_factor,
1363 					 sizeof(idev->desync_factor));
1364 			idev->desync_factor %= max_desync_factor;
1365 		} else {
1366 			idev->desync_factor = 0;
1367 		}
1368 	}
1369 
1370 	memset(&cfg, 0, sizeof(cfg));
1371 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1372 			      idev->cnf.temp_valid_lft + age);
1373 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1374 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1375 
1376 	cfg.plen = ifp->prefix_len;
1377 	tmp_tstamp = ifp->tstamp;
1378 	spin_unlock_bh(&ifp->lock);
1379 
1380 	write_unlock_bh(&idev->lock);
1381 
1382 	/* A temporary address is created only if this calculated Preferred
1383 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1384 	 * an implementation must not create a temporary address with a zero
1385 	 * Preferred Lifetime.
1386 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1387 	 * temporary addresses being generated.
1388 	 */
1389 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1390 	if (cfg.preferred_lft <= regen_advance + age) {
1391 		in6_ifa_put(ifp);
1392 		in6_dev_put(idev);
1393 		ret = -1;
1394 		goto out;
1395 	}
1396 
1397 	cfg.ifa_flags = IFA_F_TEMPORARY;
1398 	/* set in addrconf_prefix_rcv() */
1399 	if (ifp->flags & IFA_F_OPTIMISTIC)
1400 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1401 
1402 	cfg.pfx = &addr;
1403 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1404 
1405 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1406 	if (IS_ERR(ift)) {
1407 		in6_ifa_put(ifp);
1408 		in6_dev_put(idev);
1409 		pr_info("%s: retry temporary address regeneration\n", __func__);
1410 		write_lock_bh(&idev->lock);
1411 		goto retry;
1412 	}
1413 
1414 	spin_lock_bh(&ift->lock);
1415 	ift->ifpub = ifp;
1416 	ift->cstamp = now;
1417 	ift->tstamp = tmp_tstamp;
1418 	spin_unlock_bh(&ift->lock);
1419 
1420 	addrconf_dad_start(ift);
1421 	in6_ifa_put(ift);
1422 	in6_dev_put(idev);
1423 out:
1424 	return ret;
1425 }
1426 
1427 /*
1428  *	Choose an appropriate source address (RFC3484)
1429  */
1430 enum {
1431 	IPV6_SADDR_RULE_INIT = 0,
1432 	IPV6_SADDR_RULE_LOCAL,
1433 	IPV6_SADDR_RULE_SCOPE,
1434 	IPV6_SADDR_RULE_PREFERRED,
1435 #ifdef CONFIG_IPV6_MIP6
1436 	IPV6_SADDR_RULE_HOA,
1437 #endif
1438 	IPV6_SADDR_RULE_OIF,
1439 	IPV6_SADDR_RULE_LABEL,
1440 	IPV6_SADDR_RULE_PRIVACY,
1441 	IPV6_SADDR_RULE_ORCHID,
1442 	IPV6_SADDR_RULE_PREFIX,
1443 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1444 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1445 #endif
1446 	IPV6_SADDR_RULE_MAX
1447 };
1448 
1449 struct ipv6_saddr_score {
1450 	int			rule;
1451 	int			addr_type;
1452 	struct inet6_ifaddr	*ifa;
1453 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1454 	int			scopedist;
1455 	int			matchlen;
1456 };
1457 
1458 struct ipv6_saddr_dst {
1459 	const struct in6_addr *addr;
1460 	int ifindex;
1461 	int scope;
1462 	int label;
1463 	unsigned int prefs;
1464 };
1465 
1466 static inline int ipv6_saddr_preferred(int type)
1467 {
1468 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1469 		return 1;
1470 	return 0;
1471 }
1472 
1473 static bool ipv6_use_optimistic_addr(struct net *net,
1474 				     struct inet6_dev *idev)
1475 {
1476 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1477 	if (!idev)
1478 		return false;
1479 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1480 		return false;
1481 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1482 		return false;
1483 
1484 	return true;
1485 #else
1486 	return false;
1487 #endif
1488 }
1489 
1490 static bool ipv6_allow_optimistic_dad(struct net *net,
1491 				      struct inet6_dev *idev)
1492 {
1493 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1494 	if (!idev)
1495 		return false;
1496 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1497 		return false;
1498 
1499 	return true;
1500 #else
1501 	return false;
1502 #endif
1503 }
1504 
1505 static int ipv6_get_saddr_eval(struct net *net,
1506 			       struct ipv6_saddr_score *score,
1507 			       struct ipv6_saddr_dst *dst,
1508 			       int i)
1509 {
1510 	int ret;
1511 
1512 	if (i <= score->rule) {
1513 		switch (i) {
1514 		case IPV6_SADDR_RULE_SCOPE:
1515 			ret = score->scopedist;
1516 			break;
1517 		case IPV6_SADDR_RULE_PREFIX:
1518 			ret = score->matchlen;
1519 			break;
1520 		default:
1521 			ret = !!test_bit(i, score->scorebits);
1522 		}
1523 		goto out;
1524 	}
1525 
1526 	switch (i) {
1527 	case IPV6_SADDR_RULE_INIT:
1528 		/* Rule 0: remember if hiscore is not ready yet */
1529 		ret = !!score->ifa;
1530 		break;
1531 	case IPV6_SADDR_RULE_LOCAL:
1532 		/* Rule 1: Prefer same address */
1533 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1534 		break;
1535 	case IPV6_SADDR_RULE_SCOPE:
1536 		/* Rule 2: Prefer appropriate scope
1537 		 *
1538 		 *      ret
1539 		 *       ^
1540 		 *    -1 |  d 15
1541 		 *    ---+--+-+---> scope
1542 		 *       |
1543 		 *       |             d is scope of the destination.
1544 		 *  B-d  |  \
1545 		 *       |   \      <- smaller scope is better if
1546 		 *  B-15 |    \        if scope is enough for destination.
1547 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1548 		 * d-C-1 | /
1549 		 *       |/         <- greater is better
1550 		 *   -C  /             if scope is not enough for destination.
1551 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1552 		 *
1553 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1554 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1555 		 * Assume B = 0 and we get C > 29.
1556 		 */
1557 		ret = __ipv6_addr_src_scope(score->addr_type);
1558 		if (ret >= dst->scope)
1559 			ret = -ret;
1560 		else
1561 			ret -= 128;	/* 30 is enough */
1562 		score->scopedist = ret;
1563 		break;
1564 	case IPV6_SADDR_RULE_PREFERRED:
1565 	    {
1566 		/* Rule 3: Avoid deprecated and optimistic addresses */
1567 		u8 avoid = IFA_F_DEPRECATED;
1568 
1569 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1570 			avoid |= IFA_F_OPTIMISTIC;
1571 		ret = ipv6_saddr_preferred(score->addr_type) ||
1572 		      !(score->ifa->flags & avoid);
1573 		break;
1574 	    }
1575 #ifdef CONFIG_IPV6_MIP6
1576 	case IPV6_SADDR_RULE_HOA:
1577 	    {
1578 		/* Rule 4: Prefer home address */
1579 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1580 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1581 		break;
1582 	    }
1583 #endif
1584 	case IPV6_SADDR_RULE_OIF:
1585 		/* Rule 5: Prefer outgoing interface */
1586 		ret = (!dst->ifindex ||
1587 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1588 		break;
1589 	case IPV6_SADDR_RULE_LABEL:
1590 		/* Rule 6: Prefer matching label */
1591 		ret = ipv6_addr_label(net,
1592 				      &score->ifa->addr, score->addr_type,
1593 				      score->ifa->idev->dev->ifindex) == dst->label;
1594 		break;
1595 	case IPV6_SADDR_RULE_PRIVACY:
1596 	    {
1597 		/* Rule 7: Prefer public address
1598 		 * Note: prefer temporary address if use_tempaddr >= 2
1599 		 */
1600 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1601 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1602 				score->ifa->idev->cnf.use_tempaddr >= 2;
1603 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1604 		break;
1605 	    }
1606 	case IPV6_SADDR_RULE_ORCHID:
1607 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1608 		 *	    non-ORCHID vs non-ORCHID
1609 		 */
1610 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1611 			ipv6_addr_orchid(dst->addr));
1612 		break;
1613 	case IPV6_SADDR_RULE_PREFIX:
1614 		/* Rule 8: Use longest matching prefix */
1615 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1616 		if (ret > score->ifa->prefix_len)
1617 			ret = score->ifa->prefix_len;
1618 		score->matchlen = ret;
1619 		break;
1620 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1621 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1622 		/* Optimistic addresses still have lower precedence than other
1623 		 * preferred addresses.
1624 		 */
1625 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1626 		break;
1627 #endif
1628 	default:
1629 		ret = 0;
1630 	}
1631 
1632 	if (ret)
1633 		__set_bit(i, score->scorebits);
1634 	score->rule = i;
1635 out:
1636 	return ret;
1637 }
1638 
1639 static int __ipv6_dev_get_saddr(struct net *net,
1640 				struct ipv6_saddr_dst *dst,
1641 				struct inet6_dev *idev,
1642 				struct ipv6_saddr_score *scores,
1643 				int hiscore_idx)
1644 {
1645 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1646 
1647 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1648 		int i;
1649 
1650 		/*
1651 		 * - Tentative Address (RFC2462 section 5.4)
1652 		 *  - A tentative address is not considered
1653 		 *    "assigned to an interface" in the traditional
1654 		 *    sense, unless it is also flagged as optimistic.
1655 		 * - Candidate Source Address (section 4)
1656 		 *  - In any case, anycast addresses, multicast
1657 		 *    addresses, and the unspecified address MUST
1658 		 *    NOT be included in a candidate set.
1659 		 */
1660 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1661 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1662 			continue;
1663 
1664 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1665 
1666 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1667 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1668 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1669 					    idev->dev->name);
1670 			continue;
1671 		}
1672 
1673 		score->rule = -1;
1674 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1675 
1676 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1677 			int minihiscore, miniscore;
1678 
1679 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1680 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1681 
1682 			if (minihiscore > miniscore) {
1683 				if (i == IPV6_SADDR_RULE_SCOPE &&
1684 				    score->scopedist > 0) {
1685 					/*
1686 					 * special case:
1687 					 * each remaining entry
1688 					 * has too small (not enough)
1689 					 * scope, because ifa entries
1690 					 * are sorted by their scope
1691 					 * values.
1692 					 */
1693 					goto out;
1694 				}
1695 				break;
1696 			} else if (minihiscore < miniscore) {
1697 				swap(hiscore, score);
1698 				hiscore_idx = 1 - hiscore_idx;
1699 
1700 				/* restore our iterator */
1701 				score->ifa = hiscore->ifa;
1702 
1703 				break;
1704 			}
1705 		}
1706 	}
1707 out:
1708 	return hiscore_idx;
1709 }
1710 
1711 static int ipv6_get_saddr_master(struct net *net,
1712 				 const struct net_device *dst_dev,
1713 				 const struct net_device *master,
1714 				 struct ipv6_saddr_dst *dst,
1715 				 struct ipv6_saddr_score *scores,
1716 				 int hiscore_idx)
1717 {
1718 	struct inet6_dev *idev;
1719 
1720 	idev = __in6_dev_get(dst_dev);
1721 	if (idev)
1722 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1723 						   scores, hiscore_idx);
1724 
1725 	idev = __in6_dev_get(master);
1726 	if (idev)
1727 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1728 						   scores, hiscore_idx);
1729 
1730 	return hiscore_idx;
1731 }
1732 
1733 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1734 		       const struct in6_addr *daddr, unsigned int prefs,
1735 		       struct in6_addr *saddr)
1736 {
1737 	struct ipv6_saddr_score scores[2], *hiscore;
1738 	struct ipv6_saddr_dst dst;
1739 	struct inet6_dev *idev;
1740 	struct net_device *dev;
1741 	int dst_type;
1742 	bool use_oif_addr = false;
1743 	int hiscore_idx = 0;
1744 	int ret = 0;
1745 
1746 	dst_type = __ipv6_addr_type(daddr);
1747 	dst.addr = daddr;
1748 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1749 	dst.scope = __ipv6_addr_src_scope(dst_type);
1750 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1751 	dst.prefs = prefs;
1752 
1753 	scores[hiscore_idx].rule = -1;
1754 	scores[hiscore_idx].ifa = NULL;
1755 
1756 	rcu_read_lock();
1757 
1758 	/* Candidate Source Address (section 4)
1759 	 *  - multicast and link-local destination address,
1760 	 *    the set of candidate source address MUST only
1761 	 *    include addresses assigned to interfaces
1762 	 *    belonging to the same link as the outgoing
1763 	 *    interface.
1764 	 * (- For site-local destination addresses, the
1765 	 *    set of candidate source addresses MUST only
1766 	 *    include addresses assigned to interfaces
1767 	 *    belonging to the same site as the outgoing
1768 	 *    interface.)
1769 	 *  - "It is RECOMMENDED that the candidate source addresses
1770 	 *    be the set of unicast addresses assigned to the
1771 	 *    interface that will be used to send to the destination
1772 	 *    (the 'outgoing' interface)." (RFC 6724)
1773 	 */
1774 	if (dst_dev) {
1775 		idev = __in6_dev_get(dst_dev);
1776 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1777 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1778 		    (idev && idev->cnf.use_oif_addrs_only)) {
1779 			use_oif_addr = true;
1780 		}
1781 	}
1782 
1783 	if (use_oif_addr) {
1784 		if (idev)
1785 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1786 	} else {
1787 		const struct net_device *master;
1788 		int master_idx = 0;
1789 
1790 		/* if dst_dev exists and is enslaved to an L3 device, then
1791 		 * prefer addresses from dst_dev and then the master over
1792 		 * any other enslaved devices in the L3 domain.
1793 		 */
1794 		master = l3mdev_master_dev_rcu(dst_dev);
1795 		if (master) {
1796 			master_idx = master->ifindex;
1797 
1798 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1799 							    master, &dst,
1800 							    scores, hiscore_idx);
1801 
1802 			if (scores[hiscore_idx].ifa)
1803 				goto out;
1804 		}
1805 
1806 		for_each_netdev_rcu(net, dev) {
1807 			/* only consider addresses on devices in the
1808 			 * same L3 domain
1809 			 */
1810 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1811 				continue;
1812 			idev = __in6_dev_get(dev);
1813 			if (!idev)
1814 				continue;
1815 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1816 		}
1817 	}
1818 
1819 out:
1820 	hiscore = &scores[hiscore_idx];
1821 	if (!hiscore->ifa)
1822 		ret = -EADDRNOTAVAIL;
1823 	else
1824 		*saddr = hiscore->ifa->addr;
1825 
1826 	rcu_read_unlock();
1827 	return ret;
1828 }
1829 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1830 
1831 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1832 		      u32 banned_flags)
1833 {
1834 	struct inet6_ifaddr *ifp;
1835 	int err = -EADDRNOTAVAIL;
1836 
1837 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1838 		if (ifp->scope > IFA_LINK)
1839 			break;
1840 		if (ifp->scope == IFA_LINK &&
1841 		    !(ifp->flags & banned_flags)) {
1842 			*addr = ifp->addr;
1843 			err = 0;
1844 			break;
1845 		}
1846 	}
1847 	return err;
1848 }
1849 
1850 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1851 		    u32 banned_flags)
1852 {
1853 	struct inet6_dev *idev;
1854 	int err = -EADDRNOTAVAIL;
1855 
1856 	rcu_read_lock();
1857 	idev = __in6_dev_get(dev);
1858 	if (idev) {
1859 		read_lock_bh(&idev->lock);
1860 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1861 		read_unlock_bh(&idev->lock);
1862 	}
1863 	rcu_read_unlock();
1864 	return err;
1865 }
1866 
1867 static int ipv6_count_addresses(const struct inet6_dev *idev)
1868 {
1869 	const struct inet6_ifaddr *ifp;
1870 	int cnt = 0;
1871 
1872 	rcu_read_lock();
1873 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1874 		cnt++;
1875 	rcu_read_unlock();
1876 	return cnt;
1877 }
1878 
1879 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1880 		  const struct net_device *dev, int strict)
1881 {
1882 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1883 				       strict, IFA_F_TENTATIVE);
1884 }
1885 EXPORT_SYMBOL(ipv6_chk_addr);
1886 
1887 /* device argument is used to find the L3 domain of interest. If
1888  * skip_dev_check is set, then the ifp device is not checked against
1889  * the passed in dev argument. So the 2 cases for addresses checks are:
1890  *   1. does the address exist in the L3 domain that dev is part of
1891  *      (skip_dev_check = true), or
1892  *
1893  *   2. does the address exist on the specific device
1894  *      (skip_dev_check = false)
1895  */
1896 static struct net_device *
1897 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1898 			  const struct net_device *dev, bool skip_dev_check,
1899 			  int strict, u32 banned_flags)
1900 {
1901 	unsigned int hash = inet6_addr_hash(net, addr);
1902 	struct net_device *l3mdev, *ndev;
1903 	struct inet6_ifaddr *ifp;
1904 	u32 ifp_flags;
1905 
1906 	rcu_read_lock();
1907 
1908 	l3mdev = l3mdev_master_dev_rcu(dev);
1909 	if (skip_dev_check)
1910 		dev = NULL;
1911 
1912 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1913 		ndev = ifp->idev->dev;
1914 		if (!net_eq(dev_net(ndev), net))
1915 			continue;
1916 
1917 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1918 			continue;
1919 
1920 		/* Decouple optimistic from tentative for evaluation here.
1921 		 * Ban optimistic addresses explicitly, when required.
1922 		 */
1923 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1924 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1925 			    : ifp->flags;
1926 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1927 		    !(ifp_flags&banned_flags) &&
1928 		    (!dev || ndev == dev ||
1929 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1930 			rcu_read_unlock();
1931 			return ndev;
1932 		}
1933 	}
1934 
1935 	rcu_read_unlock();
1936 	return NULL;
1937 }
1938 
1939 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1940 			    const struct net_device *dev, bool skip_dev_check,
1941 			    int strict, u32 banned_flags)
1942 {
1943 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1944 					 strict, banned_flags) ? 1 : 0;
1945 }
1946 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1947 
1948 
1949 /* Compares an address/prefix_len with addresses on device @dev.
1950  * If one is found it returns true.
1951  */
1952 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1953 	const unsigned int prefix_len, struct net_device *dev)
1954 {
1955 	const struct inet6_ifaddr *ifa;
1956 	const struct inet6_dev *idev;
1957 	bool ret = false;
1958 
1959 	rcu_read_lock();
1960 	idev = __in6_dev_get(dev);
1961 	if (idev) {
1962 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1963 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1964 			if (ret)
1965 				break;
1966 		}
1967 	}
1968 	rcu_read_unlock();
1969 
1970 	return ret;
1971 }
1972 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1973 
1974 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1975 {
1976 	const struct inet6_ifaddr *ifa;
1977 	const struct inet6_dev *idev;
1978 	int	onlink;
1979 
1980 	onlink = 0;
1981 	rcu_read_lock();
1982 	idev = __in6_dev_get(dev);
1983 	if (idev) {
1984 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1985 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1986 						   ifa->prefix_len);
1987 			if (onlink)
1988 				break;
1989 		}
1990 	}
1991 	rcu_read_unlock();
1992 	return onlink;
1993 }
1994 EXPORT_SYMBOL(ipv6_chk_prefix);
1995 
1996 /**
1997  * ipv6_dev_find - find the first device with a given source address.
1998  * @net: the net namespace
1999  * @addr: the source address
2000  * @dev: used to find the L3 domain of interest
2001  *
2002  * The caller should be protected by RCU, or RTNL.
2003  */
2004 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2005 				 struct net_device *dev)
2006 {
2007 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2008 					 IFA_F_TENTATIVE);
2009 }
2010 EXPORT_SYMBOL(ipv6_dev_find);
2011 
2012 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2013 				     struct net_device *dev, int strict)
2014 {
2015 	unsigned int hash = inet6_addr_hash(net, addr);
2016 	struct inet6_ifaddr *ifp, *result = NULL;
2017 
2018 	rcu_read_lock();
2019 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2020 		if (!net_eq(dev_net(ifp->idev->dev), net))
2021 			continue;
2022 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2023 			if (!dev || ifp->idev->dev == dev ||
2024 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2025 				result = ifp;
2026 				in6_ifa_hold(ifp);
2027 				break;
2028 			}
2029 		}
2030 	}
2031 	rcu_read_unlock();
2032 
2033 	return result;
2034 }
2035 
2036 /* Gets referenced address, destroys ifaddr */
2037 
2038 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2039 {
2040 	if (dad_failed)
2041 		ifp->flags |= IFA_F_DADFAILED;
2042 
2043 	if (ifp->flags&IFA_F_TEMPORARY) {
2044 		struct inet6_ifaddr *ifpub;
2045 		spin_lock_bh(&ifp->lock);
2046 		ifpub = ifp->ifpub;
2047 		if (ifpub) {
2048 			in6_ifa_hold(ifpub);
2049 			spin_unlock_bh(&ifp->lock);
2050 			ipv6_create_tempaddr(ifpub, true);
2051 			in6_ifa_put(ifpub);
2052 		} else {
2053 			spin_unlock_bh(&ifp->lock);
2054 		}
2055 		ipv6_del_addr(ifp);
2056 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2057 		spin_lock_bh(&ifp->lock);
2058 		addrconf_del_dad_work(ifp);
2059 		ifp->flags |= IFA_F_TENTATIVE;
2060 		if (dad_failed)
2061 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2062 		spin_unlock_bh(&ifp->lock);
2063 		if (dad_failed)
2064 			ipv6_ifa_notify(0, ifp);
2065 		in6_ifa_put(ifp);
2066 	} else {
2067 		ipv6_del_addr(ifp);
2068 	}
2069 }
2070 
2071 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2072 {
2073 	int err = -ENOENT;
2074 
2075 	spin_lock_bh(&ifp->lock);
2076 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2077 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2078 		err = 0;
2079 	}
2080 	spin_unlock_bh(&ifp->lock);
2081 
2082 	return err;
2083 }
2084 
2085 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2086 {
2087 	struct inet6_dev *idev = ifp->idev;
2088 	struct net *net = dev_net(ifp->idev->dev);
2089 
2090 	if (addrconf_dad_end(ifp)) {
2091 		in6_ifa_put(ifp);
2092 		return;
2093 	}
2094 
2095 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2096 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2097 
2098 	spin_lock_bh(&ifp->lock);
2099 
2100 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2101 		struct in6_addr new_addr;
2102 		struct inet6_ifaddr *ifp2;
2103 		int retries = ifp->stable_privacy_retry + 1;
2104 		struct ifa6_config cfg = {
2105 			.pfx = &new_addr,
2106 			.plen = ifp->prefix_len,
2107 			.ifa_flags = ifp->flags,
2108 			.valid_lft = ifp->valid_lft,
2109 			.preferred_lft = ifp->prefered_lft,
2110 			.scope = ifp->scope,
2111 		};
2112 
2113 		if (retries > net->ipv6.sysctl.idgen_retries) {
2114 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2115 					     ifp->idev->dev->name);
2116 			goto errdad;
2117 		}
2118 
2119 		new_addr = ifp->addr;
2120 		if (ipv6_generate_stable_address(&new_addr, retries,
2121 						 idev))
2122 			goto errdad;
2123 
2124 		spin_unlock_bh(&ifp->lock);
2125 
2126 		if (idev->cnf.max_addresses &&
2127 		    ipv6_count_addresses(idev) >=
2128 		    idev->cnf.max_addresses)
2129 			goto lock_errdad;
2130 
2131 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2132 				     ifp->idev->dev->name);
2133 
2134 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2135 		if (IS_ERR(ifp2))
2136 			goto lock_errdad;
2137 
2138 		spin_lock_bh(&ifp2->lock);
2139 		ifp2->stable_privacy_retry = retries;
2140 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2141 		spin_unlock_bh(&ifp2->lock);
2142 
2143 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2144 		in6_ifa_put(ifp2);
2145 lock_errdad:
2146 		spin_lock_bh(&ifp->lock);
2147 	}
2148 
2149 errdad:
2150 	/* transition from _POSTDAD to _ERRDAD */
2151 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2152 	spin_unlock_bh(&ifp->lock);
2153 
2154 	addrconf_mod_dad_work(ifp, 0);
2155 	in6_ifa_put(ifp);
2156 }
2157 
2158 /* Join to solicited addr multicast group.
2159  * caller must hold RTNL */
2160 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2161 {
2162 	struct in6_addr maddr;
2163 
2164 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2165 		return;
2166 
2167 	addrconf_addr_solict_mult(addr, &maddr);
2168 	ipv6_dev_mc_inc(dev, &maddr);
2169 }
2170 
2171 /* caller must hold RTNL */
2172 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2173 {
2174 	struct in6_addr maddr;
2175 
2176 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2177 		return;
2178 
2179 	addrconf_addr_solict_mult(addr, &maddr);
2180 	__ipv6_dev_mc_dec(idev, &maddr);
2181 }
2182 
2183 /* caller must hold RTNL */
2184 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2185 {
2186 	struct in6_addr addr;
2187 
2188 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2189 		return;
2190 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2191 	if (ipv6_addr_any(&addr))
2192 		return;
2193 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2194 }
2195 
2196 /* caller must hold RTNL */
2197 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2198 {
2199 	struct in6_addr addr;
2200 
2201 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2202 		return;
2203 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2204 	if (ipv6_addr_any(&addr))
2205 		return;
2206 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2207 }
2208 
2209 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2210 {
2211 	switch (dev->addr_len) {
2212 	case ETH_ALEN:
2213 		memcpy(eui, dev->dev_addr, 3);
2214 		eui[3] = 0xFF;
2215 		eui[4] = 0xFE;
2216 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2217 		break;
2218 	case EUI64_ADDR_LEN:
2219 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2220 		eui[0] ^= 2;
2221 		break;
2222 	default:
2223 		return -1;
2224 	}
2225 
2226 	return 0;
2227 }
2228 
2229 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2230 {
2231 	union fwnet_hwaddr *ha;
2232 
2233 	if (dev->addr_len != FWNET_ALEN)
2234 		return -1;
2235 
2236 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2237 
2238 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2239 	eui[0] ^= 2;
2240 	return 0;
2241 }
2242 
2243 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2244 {
2245 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2246 	if (dev->addr_len != ARCNET_ALEN)
2247 		return -1;
2248 	memset(eui, 0, 7);
2249 	eui[7] = *(u8 *)dev->dev_addr;
2250 	return 0;
2251 }
2252 
2253 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2254 {
2255 	if (dev->addr_len != INFINIBAND_ALEN)
2256 		return -1;
2257 	memcpy(eui, dev->dev_addr + 12, 8);
2258 	eui[0] |= 2;
2259 	return 0;
2260 }
2261 
2262 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2263 {
2264 	if (addr == 0)
2265 		return -1;
2266 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2267 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2268 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2269 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2270 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2271 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2272 	eui[1] = 0;
2273 	eui[2] = 0x5E;
2274 	eui[3] = 0xFE;
2275 	memcpy(eui + 4, &addr, 4);
2276 	return 0;
2277 }
2278 
2279 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2280 {
2281 	if (dev->priv_flags & IFF_ISATAP)
2282 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2283 	return -1;
2284 }
2285 
2286 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2287 {
2288 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2289 }
2290 
2291 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2292 {
2293 	memcpy(eui, dev->perm_addr, 3);
2294 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2295 	eui[3] = 0xFF;
2296 	eui[4] = 0xFE;
2297 	eui[0] ^= 2;
2298 	return 0;
2299 }
2300 
2301 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2302 {
2303 	switch (dev->type) {
2304 	case ARPHRD_ETHER:
2305 	case ARPHRD_FDDI:
2306 		return addrconf_ifid_eui48(eui, dev);
2307 	case ARPHRD_ARCNET:
2308 		return addrconf_ifid_arcnet(eui, dev);
2309 	case ARPHRD_INFINIBAND:
2310 		return addrconf_ifid_infiniband(eui, dev);
2311 	case ARPHRD_SIT:
2312 		return addrconf_ifid_sit(eui, dev);
2313 	case ARPHRD_IPGRE:
2314 	case ARPHRD_TUNNEL:
2315 		return addrconf_ifid_gre(eui, dev);
2316 	case ARPHRD_6LOWPAN:
2317 		return addrconf_ifid_6lowpan(eui, dev);
2318 	case ARPHRD_IEEE1394:
2319 		return addrconf_ifid_ieee1394(eui, dev);
2320 	case ARPHRD_TUNNEL6:
2321 	case ARPHRD_IP6GRE:
2322 	case ARPHRD_RAWIP:
2323 		return addrconf_ifid_ip6tnl(eui, dev);
2324 	}
2325 	return -1;
2326 }
2327 
2328 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2329 {
2330 	int err = -1;
2331 	struct inet6_ifaddr *ifp;
2332 
2333 	read_lock_bh(&idev->lock);
2334 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2335 		if (ifp->scope > IFA_LINK)
2336 			break;
2337 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2338 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2339 			err = 0;
2340 			break;
2341 		}
2342 	}
2343 	read_unlock_bh(&idev->lock);
2344 	return err;
2345 }
2346 
2347 /* Generation of a randomized Interface Identifier
2348  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2349  */
2350 
2351 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2352 {
2353 regen:
2354 	get_random_bytes(&addr->s6_addr[8], 8);
2355 
2356 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2357 	 * check if generated address is not inappropriate:
2358 	 *
2359 	 * - Reserved IPv6 Interface Identifers
2360 	 * - XXX: already assigned to an address on the device
2361 	 */
2362 
2363 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2364 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2365 		goto regen;
2366 
2367 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2368 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2369 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2370 	 */
2371 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2372 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2373 		goto regen;
2374 
2375 	/* Reserved subnet anycast addresses */
2376 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2377 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2378 		goto regen;
2379 }
2380 
2381 /*
2382  *	Add prefix route.
2383  */
2384 
2385 static void
2386 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2387 		      struct net_device *dev, unsigned long expires,
2388 		      u32 flags, gfp_t gfp_flags)
2389 {
2390 	struct fib6_config cfg = {
2391 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2392 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2393 		.fc_ifindex = dev->ifindex,
2394 		.fc_expires = expires,
2395 		.fc_dst_len = plen,
2396 		.fc_flags = RTF_UP | flags,
2397 		.fc_nlinfo.nl_net = dev_net(dev),
2398 		.fc_protocol = RTPROT_KERNEL,
2399 		.fc_type = RTN_UNICAST,
2400 	};
2401 
2402 	cfg.fc_dst = *pfx;
2403 
2404 	/* Prevent useless cloning on PtP SIT.
2405 	   This thing is done here expecting that the whole
2406 	   class of non-broadcast devices need not cloning.
2407 	 */
2408 #if IS_ENABLED(CONFIG_IPV6_SIT)
2409 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2410 		cfg.fc_flags |= RTF_NONEXTHOP;
2411 #endif
2412 
2413 	ip6_route_add(&cfg, gfp_flags, NULL);
2414 }
2415 
2416 
2417 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2418 						  int plen,
2419 						  const struct net_device *dev,
2420 						  u32 flags, u32 noflags,
2421 						  bool no_gw)
2422 {
2423 	struct fib6_node *fn;
2424 	struct fib6_info *rt = NULL;
2425 	struct fib6_table *table;
2426 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2427 
2428 	table = fib6_get_table(dev_net(dev), tb_id);
2429 	if (!table)
2430 		return NULL;
2431 
2432 	rcu_read_lock();
2433 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2434 	if (!fn)
2435 		goto out;
2436 
2437 	for_each_fib6_node_rt_rcu(fn) {
2438 		/* prefix routes only use builtin fib6_nh */
2439 		if (rt->nh)
2440 			continue;
2441 
2442 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2443 			continue;
2444 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2445 			continue;
2446 		if ((rt->fib6_flags & flags) != flags)
2447 			continue;
2448 		if ((rt->fib6_flags & noflags) != 0)
2449 			continue;
2450 		if (!fib6_info_hold_safe(rt))
2451 			continue;
2452 		break;
2453 	}
2454 out:
2455 	rcu_read_unlock();
2456 	return rt;
2457 }
2458 
2459 
2460 /* Create "default" multicast route to the interface */
2461 
2462 static void addrconf_add_mroute(struct net_device *dev)
2463 {
2464 	struct fib6_config cfg = {
2465 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2466 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2467 		.fc_ifindex = dev->ifindex,
2468 		.fc_dst_len = 8,
2469 		.fc_flags = RTF_UP,
2470 		.fc_type = RTN_UNICAST,
2471 		.fc_nlinfo.nl_net = dev_net(dev),
2472 	};
2473 
2474 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2475 
2476 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2477 }
2478 
2479 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2480 {
2481 	struct inet6_dev *idev;
2482 
2483 	ASSERT_RTNL();
2484 
2485 	idev = ipv6_find_idev(dev);
2486 	if (IS_ERR(idev))
2487 		return idev;
2488 
2489 	if (idev->cnf.disable_ipv6)
2490 		return ERR_PTR(-EACCES);
2491 
2492 	/* Add default multicast route */
2493 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2494 		addrconf_add_mroute(dev);
2495 
2496 	return idev;
2497 }
2498 
2499 static void manage_tempaddrs(struct inet6_dev *idev,
2500 			     struct inet6_ifaddr *ifp,
2501 			     __u32 valid_lft, __u32 prefered_lft,
2502 			     bool create, unsigned long now)
2503 {
2504 	u32 flags;
2505 	struct inet6_ifaddr *ift;
2506 
2507 	read_lock_bh(&idev->lock);
2508 	/* update all temporary addresses in the list */
2509 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2510 		int age, max_valid, max_prefered;
2511 
2512 		if (ifp != ift->ifpub)
2513 			continue;
2514 
2515 		/* RFC 4941 section 3.3:
2516 		 * If a received option will extend the lifetime of a public
2517 		 * address, the lifetimes of temporary addresses should
2518 		 * be extended, subject to the overall constraint that no
2519 		 * temporary addresses should ever remain "valid" or "preferred"
2520 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2521 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2522 		 */
2523 		age = (now - ift->cstamp) / HZ;
2524 		max_valid = idev->cnf.temp_valid_lft - age;
2525 		if (max_valid < 0)
2526 			max_valid = 0;
2527 
2528 		max_prefered = idev->cnf.temp_prefered_lft -
2529 			       idev->desync_factor - age;
2530 		if (max_prefered < 0)
2531 			max_prefered = 0;
2532 
2533 		if (valid_lft > max_valid)
2534 			valid_lft = max_valid;
2535 
2536 		if (prefered_lft > max_prefered)
2537 			prefered_lft = max_prefered;
2538 
2539 		spin_lock(&ift->lock);
2540 		flags = ift->flags;
2541 		ift->valid_lft = valid_lft;
2542 		ift->prefered_lft = prefered_lft;
2543 		ift->tstamp = now;
2544 		if (prefered_lft > 0)
2545 			ift->flags &= ~IFA_F_DEPRECATED;
2546 
2547 		spin_unlock(&ift->lock);
2548 		if (!(flags&IFA_F_TENTATIVE))
2549 			ipv6_ifa_notify(0, ift);
2550 	}
2551 
2552 	if ((create || list_empty(&idev->tempaddr_list)) &&
2553 	    idev->cnf.use_tempaddr > 0) {
2554 		/* When a new public address is created as described
2555 		 * in [ADDRCONF], also create a new temporary address.
2556 		 * Also create a temporary address if it's enabled but
2557 		 * no temporary address currently exists.
2558 		 */
2559 		read_unlock_bh(&idev->lock);
2560 		ipv6_create_tempaddr(ifp, false);
2561 	} else {
2562 		read_unlock_bh(&idev->lock);
2563 	}
2564 }
2565 
2566 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2567 {
2568 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2569 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2570 }
2571 
2572 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2573 				 const struct prefix_info *pinfo,
2574 				 struct inet6_dev *in6_dev,
2575 				 const struct in6_addr *addr, int addr_type,
2576 				 u32 addr_flags, bool sllao, bool tokenized,
2577 				 __u32 valid_lft, u32 prefered_lft)
2578 {
2579 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2580 	int create = 0;
2581 
2582 	if (!ifp && valid_lft) {
2583 		int max_addresses = in6_dev->cnf.max_addresses;
2584 		struct ifa6_config cfg = {
2585 			.pfx = addr,
2586 			.plen = pinfo->prefix_len,
2587 			.ifa_flags = addr_flags,
2588 			.valid_lft = valid_lft,
2589 			.preferred_lft = prefered_lft,
2590 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2591 		};
2592 
2593 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2594 		if ((net->ipv6.devconf_all->optimistic_dad ||
2595 		     in6_dev->cnf.optimistic_dad) &&
2596 		    !net->ipv6.devconf_all->forwarding && sllao)
2597 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2598 #endif
2599 
2600 		/* Do not allow to create too much of autoconfigured
2601 		 * addresses; this would be too easy way to crash kernel.
2602 		 */
2603 		if (!max_addresses ||
2604 		    ipv6_count_addresses(in6_dev) < max_addresses)
2605 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2606 
2607 		if (IS_ERR_OR_NULL(ifp))
2608 			return -1;
2609 
2610 		create = 1;
2611 		spin_lock_bh(&ifp->lock);
2612 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2613 		ifp->cstamp = jiffies;
2614 		ifp->tokenized = tokenized;
2615 		spin_unlock_bh(&ifp->lock);
2616 		addrconf_dad_start(ifp);
2617 	}
2618 
2619 	if (ifp) {
2620 		u32 flags;
2621 		unsigned long now;
2622 		u32 stored_lft;
2623 
2624 		/* Update lifetime (RFC4862 5.5.3 e)
2625 		 * We deviate from RFC4862 by honoring all Valid Lifetimes to
2626 		 * improve the reaction of SLAAC to renumbering events
2627 		 * (draft-gont-6man-slaac-renum-06, Section 4.2)
2628 		 */
2629 		spin_lock_bh(&ifp->lock);
2630 		now = jiffies;
2631 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2632 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2633 		else
2634 			stored_lft = 0;
2635 
2636 		if (!create && stored_lft) {
2637 			ifp->valid_lft = valid_lft;
2638 			ifp->prefered_lft = prefered_lft;
2639 			ifp->tstamp = now;
2640 			flags = ifp->flags;
2641 			ifp->flags &= ~IFA_F_DEPRECATED;
2642 			spin_unlock_bh(&ifp->lock);
2643 
2644 			if (!(flags&IFA_F_TENTATIVE))
2645 				ipv6_ifa_notify(0, ifp);
2646 		} else
2647 			spin_unlock_bh(&ifp->lock);
2648 
2649 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2650 				 create, now);
2651 
2652 		in6_ifa_put(ifp);
2653 		addrconf_verify();
2654 	}
2655 
2656 	return 0;
2657 }
2658 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2659 
2660 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2661 {
2662 	struct prefix_info *pinfo;
2663 	__u32 valid_lft;
2664 	__u32 prefered_lft;
2665 	int addr_type, err;
2666 	u32 addr_flags = 0;
2667 	struct inet6_dev *in6_dev;
2668 	struct net *net = dev_net(dev);
2669 
2670 	pinfo = (struct prefix_info *) opt;
2671 
2672 	if (len < sizeof(struct prefix_info)) {
2673 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2674 		return;
2675 	}
2676 
2677 	/*
2678 	 *	Validation checks ([ADDRCONF], page 19)
2679 	 */
2680 
2681 	addr_type = ipv6_addr_type(&pinfo->prefix);
2682 
2683 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2684 		return;
2685 
2686 	valid_lft = ntohl(pinfo->valid);
2687 	prefered_lft = ntohl(pinfo->prefered);
2688 
2689 	if (prefered_lft > valid_lft) {
2690 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2691 		return;
2692 	}
2693 
2694 	in6_dev = in6_dev_get(dev);
2695 
2696 	if (!in6_dev) {
2697 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2698 				    dev->name);
2699 		return;
2700 	}
2701 
2702 	/*
2703 	 *	Two things going on here:
2704 	 *	1) Add routes for on-link prefixes
2705 	 *	2) Configure prefixes with the auto flag set
2706 	 */
2707 
2708 	if (pinfo->onlink) {
2709 		struct fib6_info *rt;
2710 		unsigned long rt_expires;
2711 
2712 		/* Avoid arithmetic overflow. Really, we could
2713 		 * save rt_expires in seconds, likely valid_lft,
2714 		 * but it would require division in fib gc, that it
2715 		 * not good.
2716 		 */
2717 		if (HZ > USER_HZ)
2718 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2719 		else
2720 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2721 
2722 		if (addrconf_finite_timeout(rt_expires))
2723 			rt_expires *= HZ;
2724 
2725 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2726 					       pinfo->prefix_len,
2727 					       dev,
2728 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2729 					       RTF_DEFAULT, true);
2730 
2731 		if (rt) {
2732 			/* Autoconf prefix route */
2733 			if (valid_lft == 0) {
2734 				ip6_del_rt(net, rt, false);
2735 				rt = NULL;
2736 			} else if (addrconf_finite_timeout(rt_expires)) {
2737 				/* not infinity */
2738 				fib6_set_expires(rt, jiffies + rt_expires);
2739 			} else {
2740 				fib6_clean_expires(rt);
2741 			}
2742 		} else if (valid_lft) {
2743 			clock_t expires = 0;
2744 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2745 			if (addrconf_finite_timeout(rt_expires)) {
2746 				/* not infinity */
2747 				flags |= RTF_EXPIRES;
2748 				expires = jiffies_to_clock_t(rt_expires);
2749 			}
2750 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2751 					      0, dev, expires, flags,
2752 					      GFP_ATOMIC);
2753 		}
2754 		fib6_info_release(rt);
2755 	}
2756 
2757 	/* Try to figure out our local address for this prefix */
2758 
2759 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2760 		struct in6_addr addr;
2761 		bool tokenized = false, dev_addr_generated = false;
2762 
2763 		if (pinfo->prefix_len == 64) {
2764 			memcpy(&addr, &pinfo->prefix, 8);
2765 
2766 			if (!ipv6_addr_any(&in6_dev->token)) {
2767 				read_lock_bh(&in6_dev->lock);
2768 				memcpy(addr.s6_addr + 8,
2769 				       in6_dev->token.s6_addr + 8, 8);
2770 				read_unlock_bh(&in6_dev->lock);
2771 				tokenized = true;
2772 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2773 				   !ipv6_generate_stable_address(&addr, 0,
2774 								 in6_dev)) {
2775 				addr_flags |= IFA_F_STABLE_PRIVACY;
2776 				goto ok;
2777 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2778 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2779 				goto put;
2780 			} else {
2781 				dev_addr_generated = true;
2782 			}
2783 			goto ok;
2784 		}
2785 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2786 				    pinfo->prefix_len);
2787 		goto put;
2788 
2789 ok:
2790 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2791 						   &addr, addr_type,
2792 						   addr_flags, sllao,
2793 						   tokenized, valid_lft,
2794 						   prefered_lft);
2795 		if (err)
2796 			goto put;
2797 
2798 		/* Ignore error case here because previous prefix add addr was
2799 		 * successful which will be notified.
2800 		 */
2801 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2802 					      addr_type, addr_flags, sllao,
2803 					      tokenized, valid_lft,
2804 					      prefered_lft,
2805 					      dev_addr_generated);
2806 	}
2807 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2808 put:
2809 	in6_dev_put(in6_dev);
2810 }
2811 
2812 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2813 		struct in6_ifreq *ireq)
2814 {
2815 	struct ip_tunnel_parm p = { };
2816 	int err;
2817 
2818 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2819 		return -EADDRNOTAVAIL;
2820 
2821 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2822 	p.iph.version = 4;
2823 	p.iph.ihl = 5;
2824 	p.iph.protocol = IPPROTO_IPV6;
2825 	p.iph.ttl = 64;
2826 
2827 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2828 		return -EOPNOTSUPP;
2829 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2830 	if (err)
2831 		return err;
2832 
2833 	dev = __dev_get_by_name(net, p.name);
2834 	if (!dev)
2835 		return -ENOBUFS;
2836 	return dev_open(dev, NULL);
2837 }
2838 
2839 /*
2840  *	Set destination address.
2841  *	Special case for SIT interfaces where we create a new "virtual"
2842  *	device.
2843  */
2844 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2845 {
2846 	struct net_device *dev;
2847 	struct in6_ifreq ireq;
2848 	int err = -ENODEV;
2849 
2850 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2851 		return -ENODEV;
2852 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2853 		return -EFAULT;
2854 
2855 	rtnl_lock();
2856 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2857 	if (dev && dev->type == ARPHRD_SIT)
2858 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2859 	rtnl_unlock();
2860 	return err;
2861 }
2862 
2863 static int ipv6_mc_config(struct sock *sk, bool join,
2864 			  const struct in6_addr *addr, int ifindex)
2865 {
2866 	int ret;
2867 
2868 	ASSERT_RTNL();
2869 
2870 	lock_sock(sk);
2871 	if (join)
2872 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2873 	else
2874 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2875 	release_sock(sk);
2876 
2877 	return ret;
2878 }
2879 
2880 /*
2881  *	Manual configuration of address on an interface
2882  */
2883 static int inet6_addr_add(struct net *net, int ifindex,
2884 			  struct ifa6_config *cfg,
2885 			  struct netlink_ext_ack *extack)
2886 {
2887 	struct inet6_ifaddr *ifp;
2888 	struct inet6_dev *idev;
2889 	struct net_device *dev;
2890 	unsigned long timeout;
2891 	clock_t expires;
2892 	u32 flags;
2893 
2894 	ASSERT_RTNL();
2895 
2896 	if (cfg->plen > 128)
2897 		return -EINVAL;
2898 
2899 	/* check the lifetime */
2900 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2901 		return -EINVAL;
2902 
2903 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2904 		return -EINVAL;
2905 
2906 	dev = __dev_get_by_index(net, ifindex);
2907 	if (!dev)
2908 		return -ENODEV;
2909 
2910 	idev = addrconf_add_dev(dev);
2911 	if (IS_ERR(idev))
2912 		return PTR_ERR(idev);
2913 
2914 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2915 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2916 					 true, cfg->pfx, ifindex);
2917 
2918 		if (ret < 0)
2919 			return ret;
2920 	}
2921 
2922 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2923 
2924 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2925 	if (addrconf_finite_timeout(timeout)) {
2926 		expires = jiffies_to_clock_t(timeout * HZ);
2927 		cfg->valid_lft = timeout;
2928 		flags = RTF_EXPIRES;
2929 	} else {
2930 		expires = 0;
2931 		flags = 0;
2932 		cfg->ifa_flags |= IFA_F_PERMANENT;
2933 	}
2934 
2935 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2936 	if (addrconf_finite_timeout(timeout)) {
2937 		if (timeout == 0)
2938 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2939 		cfg->preferred_lft = timeout;
2940 	}
2941 
2942 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2943 	if (!IS_ERR(ifp)) {
2944 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2945 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2946 					      ifp->rt_priority, dev, expires,
2947 					      flags, GFP_KERNEL);
2948 		}
2949 
2950 		/* Send a netlink notification if DAD is enabled and
2951 		 * optimistic flag is not set
2952 		 */
2953 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2954 			ipv6_ifa_notify(0, ifp);
2955 		/*
2956 		 * Note that section 3.1 of RFC 4429 indicates
2957 		 * that the Optimistic flag should not be set for
2958 		 * manually configured addresses
2959 		 */
2960 		addrconf_dad_start(ifp);
2961 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2962 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2963 					 cfg->preferred_lft, true, jiffies);
2964 		in6_ifa_put(ifp);
2965 		addrconf_verify_rtnl();
2966 		return 0;
2967 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2968 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2969 			       cfg->pfx, ifindex);
2970 	}
2971 
2972 	return PTR_ERR(ifp);
2973 }
2974 
2975 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2976 			  const struct in6_addr *pfx, unsigned int plen)
2977 {
2978 	struct inet6_ifaddr *ifp;
2979 	struct inet6_dev *idev;
2980 	struct net_device *dev;
2981 
2982 	if (plen > 128)
2983 		return -EINVAL;
2984 
2985 	dev = __dev_get_by_index(net, ifindex);
2986 	if (!dev)
2987 		return -ENODEV;
2988 
2989 	idev = __in6_dev_get(dev);
2990 	if (!idev)
2991 		return -ENXIO;
2992 
2993 	read_lock_bh(&idev->lock);
2994 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2995 		if (ifp->prefix_len == plen &&
2996 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2997 			in6_ifa_hold(ifp);
2998 			read_unlock_bh(&idev->lock);
2999 
3000 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3001 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3002 				manage_tempaddrs(idev, ifp, 0, 0, false,
3003 						 jiffies);
3004 			ipv6_del_addr(ifp);
3005 			addrconf_verify_rtnl();
3006 			if (ipv6_addr_is_multicast(pfx)) {
3007 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3008 					       false, pfx, dev->ifindex);
3009 			}
3010 			return 0;
3011 		}
3012 	}
3013 	read_unlock_bh(&idev->lock);
3014 	return -EADDRNOTAVAIL;
3015 }
3016 
3017 
3018 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3019 {
3020 	struct ifa6_config cfg = {
3021 		.ifa_flags = IFA_F_PERMANENT,
3022 		.preferred_lft = INFINITY_LIFE_TIME,
3023 		.valid_lft = INFINITY_LIFE_TIME,
3024 	};
3025 	struct in6_ifreq ireq;
3026 	int err;
3027 
3028 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3029 		return -EPERM;
3030 
3031 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3032 		return -EFAULT;
3033 
3034 	cfg.pfx = &ireq.ifr6_addr;
3035 	cfg.plen = ireq.ifr6_prefixlen;
3036 
3037 	rtnl_lock();
3038 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3039 	rtnl_unlock();
3040 	return err;
3041 }
3042 
3043 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3044 {
3045 	struct in6_ifreq ireq;
3046 	int err;
3047 
3048 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3049 		return -EPERM;
3050 
3051 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3052 		return -EFAULT;
3053 
3054 	rtnl_lock();
3055 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3056 			     ireq.ifr6_prefixlen);
3057 	rtnl_unlock();
3058 	return err;
3059 }
3060 
3061 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3062 		     int plen, int scope)
3063 {
3064 	struct inet6_ifaddr *ifp;
3065 	struct ifa6_config cfg = {
3066 		.pfx = addr,
3067 		.plen = plen,
3068 		.ifa_flags = IFA_F_PERMANENT,
3069 		.valid_lft = INFINITY_LIFE_TIME,
3070 		.preferred_lft = INFINITY_LIFE_TIME,
3071 		.scope = scope
3072 	};
3073 
3074 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3075 	if (!IS_ERR(ifp)) {
3076 		spin_lock_bh(&ifp->lock);
3077 		ifp->flags &= ~IFA_F_TENTATIVE;
3078 		spin_unlock_bh(&ifp->lock);
3079 		rt_genid_bump_ipv6(dev_net(idev->dev));
3080 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3081 		in6_ifa_put(ifp);
3082 	}
3083 }
3084 
3085 #if IS_ENABLED(CONFIG_IPV6_SIT)
3086 static void sit_add_v4_addrs(struct inet6_dev *idev)
3087 {
3088 	struct in6_addr addr;
3089 	struct net_device *dev;
3090 	struct net *net = dev_net(idev->dev);
3091 	int scope, plen;
3092 	u32 pflags = 0;
3093 
3094 	ASSERT_RTNL();
3095 
3096 	memset(&addr, 0, sizeof(struct in6_addr));
3097 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3098 
3099 	if (idev->dev->flags&IFF_POINTOPOINT) {
3100 		addr.s6_addr32[0] = htonl(0xfe800000);
3101 		scope = IFA_LINK;
3102 		plen = 64;
3103 	} else {
3104 		scope = IPV6_ADDR_COMPATv4;
3105 		plen = 96;
3106 		pflags |= RTF_NONEXTHOP;
3107 	}
3108 
3109 	if (addr.s6_addr32[3]) {
3110 		add_addr(idev, &addr, plen, scope);
3111 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3112 				      GFP_KERNEL);
3113 		return;
3114 	}
3115 
3116 	for_each_netdev(net, dev) {
3117 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3118 		if (in_dev && (dev->flags & IFF_UP)) {
3119 			struct in_ifaddr *ifa;
3120 			int flag = scope;
3121 
3122 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3123 				addr.s6_addr32[3] = ifa->ifa_local;
3124 
3125 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3126 					continue;
3127 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3128 					if (idev->dev->flags&IFF_POINTOPOINT)
3129 						continue;
3130 					flag |= IFA_HOST;
3131 				}
3132 
3133 				add_addr(idev, &addr, plen, flag);
3134 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3135 						      0, pflags, GFP_KERNEL);
3136 			}
3137 		}
3138 	}
3139 }
3140 #endif
3141 
3142 static void init_loopback(struct net_device *dev)
3143 {
3144 	struct inet6_dev  *idev;
3145 
3146 	/* ::1 */
3147 
3148 	ASSERT_RTNL();
3149 
3150 	idev = ipv6_find_idev(dev);
3151 	if (IS_ERR(idev)) {
3152 		pr_debug("%s: add_dev failed\n", __func__);
3153 		return;
3154 	}
3155 
3156 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3157 }
3158 
3159 void addrconf_add_linklocal(struct inet6_dev *idev,
3160 			    const struct in6_addr *addr, u32 flags)
3161 {
3162 	struct ifa6_config cfg = {
3163 		.pfx = addr,
3164 		.plen = 64,
3165 		.ifa_flags = flags | IFA_F_PERMANENT,
3166 		.valid_lft = INFINITY_LIFE_TIME,
3167 		.preferred_lft = INFINITY_LIFE_TIME,
3168 		.scope = IFA_LINK
3169 	};
3170 	struct inet6_ifaddr *ifp;
3171 
3172 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3173 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3174 	     idev->cnf.optimistic_dad) &&
3175 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3176 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3177 #endif
3178 
3179 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3180 	if (!IS_ERR(ifp)) {
3181 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3182 				      0, 0, GFP_ATOMIC);
3183 		addrconf_dad_start(ifp);
3184 		in6_ifa_put(ifp);
3185 	}
3186 }
3187 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3188 
3189 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3190 {
3191 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3192 		return true;
3193 
3194 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3195 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3196 		return true;
3197 
3198 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3199 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3200 		return true;
3201 
3202 	return false;
3203 }
3204 
3205 static int ipv6_generate_stable_address(struct in6_addr *address,
3206 					u8 dad_count,
3207 					const struct inet6_dev *idev)
3208 {
3209 	static DEFINE_SPINLOCK(lock);
3210 	static __u32 digest[SHA1_DIGEST_WORDS];
3211 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3212 
3213 	static union {
3214 		char __data[SHA1_BLOCK_SIZE];
3215 		struct {
3216 			struct in6_addr secret;
3217 			__be32 prefix[2];
3218 			unsigned char hwaddr[MAX_ADDR_LEN];
3219 			u8 dad_count;
3220 		} __packed;
3221 	} data;
3222 
3223 	struct in6_addr secret;
3224 	struct in6_addr temp;
3225 	struct net *net = dev_net(idev->dev);
3226 
3227 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3228 
3229 	if (idev->cnf.stable_secret.initialized)
3230 		secret = idev->cnf.stable_secret.secret;
3231 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3232 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3233 	else
3234 		return -1;
3235 
3236 retry:
3237 	spin_lock_bh(&lock);
3238 
3239 	sha1_init(digest);
3240 	memset(&data, 0, sizeof(data));
3241 	memset(workspace, 0, sizeof(workspace));
3242 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3243 	data.prefix[0] = address->s6_addr32[0];
3244 	data.prefix[1] = address->s6_addr32[1];
3245 	data.secret = secret;
3246 	data.dad_count = dad_count;
3247 
3248 	sha1_transform(digest, data.__data, workspace);
3249 
3250 	temp = *address;
3251 	temp.s6_addr32[2] = (__force __be32)digest[0];
3252 	temp.s6_addr32[3] = (__force __be32)digest[1];
3253 
3254 	spin_unlock_bh(&lock);
3255 
3256 	if (ipv6_reserved_interfaceid(temp)) {
3257 		dad_count++;
3258 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3259 			return -1;
3260 		goto retry;
3261 	}
3262 
3263 	*address = temp;
3264 	return 0;
3265 }
3266 
3267 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3268 {
3269 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3270 
3271 	if (s->initialized)
3272 		return;
3273 	s = &idev->cnf.stable_secret;
3274 	get_random_bytes(&s->secret, sizeof(s->secret));
3275 	s->initialized = true;
3276 }
3277 
3278 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3279 {
3280 	struct in6_addr addr;
3281 
3282 	/* no link local addresses on L3 master devices */
3283 	if (netif_is_l3_master(idev->dev))
3284 		return;
3285 
3286 	/* no link local addresses on devices flagged as slaves */
3287 	if (idev->dev->flags & IFF_SLAVE)
3288 		return;
3289 
3290 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3291 
3292 	switch (idev->cnf.addr_gen_mode) {
3293 	case IN6_ADDR_GEN_MODE_RANDOM:
3294 		ipv6_gen_mode_random_init(idev);
3295 		fallthrough;
3296 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3297 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3298 			addrconf_add_linklocal(idev, &addr,
3299 					       IFA_F_STABLE_PRIVACY);
3300 		else if (prefix_route)
3301 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3302 					      0, 0, GFP_KERNEL);
3303 		break;
3304 	case IN6_ADDR_GEN_MODE_EUI64:
3305 		/* addrconf_add_linklocal also adds a prefix_route and we
3306 		 * only need to care about prefix routes if ipv6_generate_eui64
3307 		 * couldn't generate one.
3308 		 */
3309 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3310 			addrconf_add_linklocal(idev, &addr, 0);
3311 		else if (prefix_route)
3312 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3313 					      0, 0, GFP_KERNEL);
3314 		break;
3315 	case IN6_ADDR_GEN_MODE_NONE:
3316 	default:
3317 		/* will not add any link local address */
3318 		break;
3319 	}
3320 }
3321 
3322 static void addrconf_dev_config(struct net_device *dev)
3323 {
3324 	struct inet6_dev *idev;
3325 
3326 	ASSERT_RTNL();
3327 
3328 	if ((dev->type != ARPHRD_ETHER) &&
3329 	    (dev->type != ARPHRD_FDDI) &&
3330 	    (dev->type != ARPHRD_ARCNET) &&
3331 	    (dev->type != ARPHRD_INFINIBAND) &&
3332 	    (dev->type != ARPHRD_IEEE1394) &&
3333 	    (dev->type != ARPHRD_TUNNEL6) &&
3334 	    (dev->type != ARPHRD_6LOWPAN) &&
3335 	    (dev->type != ARPHRD_IP6GRE) &&
3336 	    (dev->type != ARPHRD_IPGRE) &&
3337 	    (dev->type != ARPHRD_TUNNEL) &&
3338 	    (dev->type != ARPHRD_NONE) &&
3339 	    (dev->type != ARPHRD_RAWIP)) {
3340 		/* Alas, we support only Ethernet autoconfiguration. */
3341 		idev = __in6_dev_get(dev);
3342 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3343 		    dev->flags & IFF_MULTICAST)
3344 			ipv6_mc_up(idev);
3345 		return;
3346 	}
3347 
3348 	idev = addrconf_add_dev(dev);
3349 	if (IS_ERR(idev))
3350 		return;
3351 
3352 	/* this device type has no EUI support */
3353 	if (dev->type == ARPHRD_NONE &&
3354 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3355 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3356 
3357 	addrconf_addr_gen(idev, false);
3358 }
3359 
3360 #if IS_ENABLED(CONFIG_IPV6_SIT)
3361 static void addrconf_sit_config(struct net_device *dev)
3362 {
3363 	struct inet6_dev *idev;
3364 
3365 	ASSERT_RTNL();
3366 
3367 	/*
3368 	 * Configure the tunnel with one of our IPv4
3369 	 * addresses... we should configure all of
3370 	 * our v4 addrs in the tunnel
3371 	 */
3372 
3373 	idev = ipv6_find_idev(dev);
3374 	if (IS_ERR(idev)) {
3375 		pr_debug("%s: add_dev failed\n", __func__);
3376 		return;
3377 	}
3378 
3379 	if (dev->priv_flags & IFF_ISATAP) {
3380 		addrconf_addr_gen(idev, false);
3381 		return;
3382 	}
3383 
3384 	sit_add_v4_addrs(idev);
3385 
3386 	if (dev->flags&IFF_POINTOPOINT)
3387 		addrconf_add_mroute(dev);
3388 }
3389 #endif
3390 
3391 #if IS_ENABLED(CONFIG_NET_IPGRE)
3392 static void addrconf_gre_config(struct net_device *dev)
3393 {
3394 	struct inet6_dev *idev;
3395 
3396 	ASSERT_RTNL();
3397 
3398 	idev = ipv6_find_idev(dev);
3399 	if (IS_ERR(idev)) {
3400 		pr_debug("%s: add_dev failed\n", __func__);
3401 		return;
3402 	}
3403 
3404 	addrconf_addr_gen(idev, true);
3405 	if (dev->flags & IFF_POINTOPOINT)
3406 		addrconf_add_mroute(dev);
3407 }
3408 #endif
3409 
3410 static int fixup_permanent_addr(struct net *net,
3411 				struct inet6_dev *idev,
3412 				struct inet6_ifaddr *ifp)
3413 {
3414 	/* !fib6_node means the host route was removed from the
3415 	 * FIB, for example, if 'lo' device is taken down. In that
3416 	 * case regenerate the host route.
3417 	 */
3418 	if (!ifp->rt || !ifp->rt->fib6_node) {
3419 		struct fib6_info *f6i, *prev;
3420 
3421 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3422 					 GFP_ATOMIC);
3423 		if (IS_ERR(f6i))
3424 			return PTR_ERR(f6i);
3425 
3426 		/* ifp->rt can be accessed outside of rtnl */
3427 		spin_lock(&ifp->lock);
3428 		prev = ifp->rt;
3429 		ifp->rt = f6i;
3430 		spin_unlock(&ifp->lock);
3431 
3432 		fib6_info_release(prev);
3433 	}
3434 
3435 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3436 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3437 				      ifp->rt_priority, idev->dev, 0, 0,
3438 				      GFP_ATOMIC);
3439 	}
3440 
3441 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3442 		addrconf_dad_start(ifp);
3443 
3444 	return 0;
3445 }
3446 
3447 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3448 {
3449 	struct inet6_ifaddr *ifp, *tmp;
3450 	struct inet6_dev *idev;
3451 
3452 	idev = __in6_dev_get(dev);
3453 	if (!idev)
3454 		return;
3455 
3456 	write_lock_bh(&idev->lock);
3457 
3458 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3459 		if ((ifp->flags & IFA_F_PERMANENT) &&
3460 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3461 			write_unlock_bh(&idev->lock);
3462 			in6_ifa_hold(ifp);
3463 			ipv6_del_addr(ifp);
3464 			write_lock_bh(&idev->lock);
3465 
3466 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3467 					     idev->dev->name, &ifp->addr);
3468 		}
3469 	}
3470 
3471 	write_unlock_bh(&idev->lock);
3472 }
3473 
3474 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3475 			   void *ptr)
3476 {
3477 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3478 	struct netdev_notifier_change_info *change_info;
3479 	struct netdev_notifier_changeupper_info *info;
3480 	struct inet6_dev *idev = __in6_dev_get(dev);
3481 	struct net *net = dev_net(dev);
3482 	int run_pending = 0;
3483 	int err;
3484 
3485 	switch (event) {
3486 	case NETDEV_REGISTER:
3487 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3488 			idev = ipv6_add_dev(dev);
3489 			if (IS_ERR(idev))
3490 				return notifier_from_errno(PTR_ERR(idev));
3491 		}
3492 		break;
3493 
3494 	case NETDEV_CHANGEMTU:
3495 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3496 		if (dev->mtu < IPV6_MIN_MTU) {
3497 			addrconf_ifdown(dev, dev != net->loopback_dev);
3498 			break;
3499 		}
3500 
3501 		if (idev) {
3502 			rt6_mtu_change(dev, dev->mtu);
3503 			idev->cnf.mtu6 = dev->mtu;
3504 			break;
3505 		}
3506 
3507 		/* allocate new idev */
3508 		idev = ipv6_add_dev(dev);
3509 		if (IS_ERR(idev))
3510 			break;
3511 
3512 		/* device is still not ready */
3513 		if (!(idev->if_flags & IF_READY))
3514 			break;
3515 
3516 		run_pending = 1;
3517 		fallthrough;
3518 	case NETDEV_UP:
3519 	case NETDEV_CHANGE:
3520 		if (dev->flags & IFF_SLAVE)
3521 			break;
3522 
3523 		if (idev && idev->cnf.disable_ipv6)
3524 			break;
3525 
3526 		if (event == NETDEV_UP) {
3527 			/* restore routes for permanent addresses */
3528 			addrconf_permanent_addr(net, dev);
3529 
3530 			if (!addrconf_link_ready(dev)) {
3531 				/* device is not ready yet. */
3532 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3533 					 dev->name);
3534 				break;
3535 			}
3536 
3537 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3538 				idev = ipv6_add_dev(dev);
3539 
3540 			if (!IS_ERR_OR_NULL(idev)) {
3541 				idev->if_flags |= IF_READY;
3542 				run_pending = 1;
3543 			}
3544 		} else if (event == NETDEV_CHANGE) {
3545 			if (!addrconf_link_ready(dev)) {
3546 				/* device is still not ready. */
3547 				rt6_sync_down_dev(dev, event);
3548 				break;
3549 			}
3550 
3551 			if (!IS_ERR_OR_NULL(idev)) {
3552 				if (idev->if_flags & IF_READY) {
3553 					/* device is already configured -
3554 					 * but resend MLD reports, we might
3555 					 * have roamed and need to update
3556 					 * multicast snooping switches
3557 					 */
3558 					ipv6_mc_up(idev);
3559 					change_info = ptr;
3560 					if (change_info->flags_changed & IFF_NOARP)
3561 						addrconf_dad_run(idev, true);
3562 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3563 					break;
3564 				}
3565 				idev->if_flags |= IF_READY;
3566 			}
3567 
3568 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3569 				dev->name);
3570 
3571 			run_pending = 1;
3572 		}
3573 
3574 		switch (dev->type) {
3575 #if IS_ENABLED(CONFIG_IPV6_SIT)
3576 		case ARPHRD_SIT:
3577 			addrconf_sit_config(dev);
3578 			break;
3579 #endif
3580 #if IS_ENABLED(CONFIG_NET_IPGRE)
3581 		case ARPHRD_IPGRE:
3582 			addrconf_gre_config(dev);
3583 			break;
3584 #endif
3585 		case ARPHRD_LOOPBACK:
3586 			init_loopback(dev);
3587 			break;
3588 
3589 		default:
3590 			addrconf_dev_config(dev);
3591 			break;
3592 		}
3593 
3594 		if (!IS_ERR_OR_NULL(idev)) {
3595 			if (run_pending)
3596 				addrconf_dad_run(idev, false);
3597 
3598 			/* Device has an address by now */
3599 			rt6_sync_up(dev, RTNH_F_DEAD);
3600 
3601 			/*
3602 			 * If the MTU changed during the interface down,
3603 			 * when the interface up, the changed MTU must be
3604 			 * reflected in the idev as well as routers.
3605 			 */
3606 			if (idev->cnf.mtu6 != dev->mtu &&
3607 			    dev->mtu >= IPV6_MIN_MTU) {
3608 				rt6_mtu_change(dev, dev->mtu);
3609 				idev->cnf.mtu6 = dev->mtu;
3610 			}
3611 			idev->tstamp = jiffies;
3612 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3613 
3614 			/*
3615 			 * If the changed mtu during down is lower than
3616 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3617 			 */
3618 			if (dev->mtu < IPV6_MIN_MTU)
3619 				addrconf_ifdown(dev, dev != net->loopback_dev);
3620 		}
3621 		break;
3622 
3623 	case NETDEV_DOWN:
3624 	case NETDEV_UNREGISTER:
3625 		/*
3626 		 *	Remove all addresses from this interface.
3627 		 */
3628 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3629 		break;
3630 
3631 	case NETDEV_CHANGENAME:
3632 		if (idev) {
3633 			snmp6_unregister_dev(idev);
3634 			addrconf_sysctl_unregister(idev);
3635 			err = addrconf_sysctl_register(idev);
3636 			if (err)
3637 				return notifier_from_errno(err);
3638 			err = snmp6_register_dev(idev);
3639 			if (err) {
3640 				addrconf_sysctl_unregister(idev);
3641 				return notifier_from_errno(err);
3642 			}
3643 		}
3644 		break;
3645 
3646 	case NETDEV_PRE_TYPE_CHANGE:
3647 	case NETDEV_POST_TYPE_CHANGE:
3648 		if (idev)
3649 			addrconf_type_change(dev, event);
3650 		break;
3651 
3652 	case NETDEV_CHANGEUPPER:
3653 		info = ptr;
3654 
3655 		/* flush all routes if dev is linked to or unlinked from
3656 		 * an L3 master device (e.g., VRF)
3657 		 */
3658 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3659 			addrconf_ifdown(dev, false);
3660 	}
3661 
3662 	return NOTIFY_OK;
3663 }
3664 
3665 /*
3666  *	addrconf module should be notified of a device going up
3667  */
3668 static struct notifier_block ipv6_dev_notf = {
3669 	.notifier_call = addrconf_notify,
3670 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3671 };
3672 
3673 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3674 {
3675 	struct inet6_dev *idev;
3676 	ASSERT_RTNL();
3677 
3678 	idev = __in6_dev_get(dev);
3679 
3680 	if (event == NETDEV_POST_TYPE_CHANGE)
3681 		ipv6_mc_remap(idev);
3682 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3683 		ipv6_mc_unmap(idev);
3684 }
3685 
3686 static bool addr_is_local(const struct in6_addr *addr)
3687 {
3688 	return ipv6_addr_type(addr) &
3689 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3690 }
3691 
3692 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3693 {
3694 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3695 	struct net *net = dev_net(dev);
3696 	struct inet6_dev *idev;
3697 	struct inet6_ifaddr *ifa, *tmp;
3698 	bool keep_addr = false;
3699 	int state, i;
3700 
3701 	ASSERT_RTNL();
3702 
3703 	rt6_disable_ip(dev, event);
3704 
3705 	idev = __in6_dev_get(dev);
3706 	if (!idev)
3707 		return -ENODEV;
3708 
3709 	/*
3710 	 * Step 1: remove reference to ipv6 device from parent device.
3711 	 *	   Do not dev_put!
3712 	 */
3713 	if (unregister) {
3714 		idev->dead = 1;
3715 
3716 		/* protected by rtnl_lock */
3717 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3718 
3719 		/* Step 1.5: remove snmp6 entry */
3720 		snmp6_unregister_dev(idev);
3721 
3722 	}
3723 
3724 	/* combine the user config with event to determine if permanent
3725 	 * addresses are to be removed from address hash table
3726 	 */
3727 	if (!unregister && !idev->cnf.disable_ipv6) {
3728 		/* aggregate the system setting and interface setting */
3729 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3730 
3731 		if (!_keep_addr)
3732 			_keep_addr = idev->cnf.keep_addr_on_down;
3733 
3734 		keep_addr = (_keep_addr > 0);
3735 	}
3736 
3737 	/* Step 2: clear hash table */
3738 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3739 		struct hlist_head *h = &inet6_addr_lst[i];
3740 
3741 		spin_lock_bh(&addrconf_hash_lock);
3742 restart:
3743 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3744 			if (ifa->idev == idev) {
3745 				addrconf_del_dad_work(ifa);
3746 				/* combined flag + permanent flag decide if
3747 				 * address is retained on a down event
3748 				 */
3749 				if (!keep_addr ||
3750 				    !(ifa->flags & IFA_F_PERMANENT) ||
3751 				    addr_is_local(&ifa->addr)) {
3752 					hlist_del_init_rcu(&ifa->addr_lst);
3753 					goto restart;
3754 				}
3755 			}
3756 		}
3757 		spin_unlock_bh(&addrconf_hash_lock);
3758 	}
3759 
3760 	write_lock_bh(&idev->lock);
3761 
3762 	addrconf_del_rs_timer(idev);
3763 
3764 	/* Step 2: clear flags for stateless addrconf */
3765 	if (!unregister)
3766 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3767 
3768 	/* Step 3: clear tempaddr list */
3769 	while (!list_empty(&idev->tempaddr_list)) {
3770 		ifa = list_first_entry(&idev->tempaddr_list,
3771 				       struct inet6_ifaddr, tmp_list);
3772 		list_del(&ifa->tmp_list);
3773 		write_unlock_bh(&idev->lock);
3774 		spin_lock_bh(&ifa->lock);
3775 
3776 		if (ifa->ifpub) {
3777 			in6_ifa_put(ifa->ifpub);
3778 			ifa->ifpub = NULL;
3779 		}
3780 		spin_unlock_bh(&ifa->lock);
3781 		in6_ifa_put(ifa);
3782 		write_lock_bh(&idev->lock);
3783 	}
3784 
3785 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3786 		struct fib6_info *rt = NULL;
3787 		bool keep;
3788 
3789 		addrconf_del_dad_work(ifa);
3790 
3791 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3792 			!addr_is_local(&ifa->addr);
3793 
3794 		write_unlock_bh(&idev->lock);
3795 		spin_lock_bh(&ifa->lock);
3796 
3797 		if (keep) {
3798 			/* set state to skip the notifier below */
3799 			state = INET6_IFADDR_STATE_DEAD;
3800 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3801 			if (!(ifa->flags & IFA_F_NODAD))
3802 				ifa->flags |= IFA_F_TENTATIVE;
3803 
3804 			rt = ifa->rt;
3805 			ifa->rt = NULL;
3806 		} else {
3807 			state = ifa->state;
3808 			ifa->state = INET6_IFADDR_STATE_DEAD;
3809 		}
3810 
3811 		spin_unlock_bh(&ifa->lock);
3812 
3813 		if (rt)
3814 			ip6_del_rt(net, rt, false);
3815 
3816 		if (state != INET6_IFADDR_STATE_DEAD) {
3817 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3818 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3819 		} else {
3820 			if (idev->cnf.forwarding)
3821 				addrconf_leave_anycast(ifa);
3822 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3823 		}
3824 
3825 		write_lock_bh(&idev->lock);
3826 		if (!keep) {
3827 			list_del_rcu(&ifa->if_list);
3828 			in6_ifa_put(ifa);
3829 		}
3830 	}
3831 
3832 	write_unlock_bh(&idev->lock);
3833 
3834 	/* Step 5: Discard anycast and multicast list */
3835 	if (unregister) {
3836 		ipv6_ac_destroy_dev(idev);
3837 		ipv6_mc_destroy_dev(idev);
3838 	} else {
3839 		ipv6_mc_down(idev);
3840 	}
3841 
3842 	idev->tstamp = jiffies;
3843 
3844 	/* Last: Shot the device (if unregistered) */
3845 	if (unregister) {
3846 		addrconf_sysctl_unregister(idev);
3847 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3848 		neigh_ifdown(&nd_tbl, dev);
3849 		in6_dev_put(idev);
3850 	}
3851 	return 0;
3852 }
3853 
3854 static void addrconf_rs_timer(struct timer_list *t)
3855 {
3856 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3857 	struct net_device *dev = idev->dev;
3858 	struct in6_addr lladdr;
3859 
3860 	write_lock(&idev->lock);
3861 	if (idev->dead || !(idev->if_flags & IF_READY))
3862 		goto out;
3863 
3864 	if (!ipv6_accept_ra(idev))
3865 		goto out;
3866 
3867 	/* Announcement received after solicitation was sent */
3868 	if (idev->if_flags & IF_RA_RCVD)
3869 		goto out;
3870 
3871 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3872 		write_unlock(&idev->lock);
3873 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3874 			ndisc_send_rs(dev, &lladdr,
3875 				      &in6addr_linklocal_allrouters);
3876 		else
3877 			goto put;
3878 
3879 		write_lock(&idev->lock);
3880 		idev->rs_interval = rfc3315_s14_backoff_update(
3881 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3882 		/* The wait after the last probe can be shorter */
3883 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3884 					     idev->cnf.rtr_solicits) ?
3885 				      idev->cnf.rtr_solicit_delay :
3886 				      idev->rs_interval);
3887 	} else {
3888 		/*
3889 		 * Note: we do not support deprecated "all on-link"
3890 		 * assumption any longer.
3891 		 */
3892 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3893 	}
3894 
3895 out:
3896 	write_unlock(&idev->lock);
3897 put:
3898 	in6_dev_put(idev);
3899 }
3900 
3901 /*
3902  *	Duplicate Address Detection
3903  */
3904 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3905 {
3906 	unsigned long rand_num;
3907 	struct inet6_dev *idev = ifp->idev;
3908 	u64 nonce;
3909 
3910 	if (ifp->flags & IFA_F_OPTIMISTIC)
3911 		rand_num = 0;
3912 	else
3913 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3914 
3915 	nonce = 0;
3916 	if (idev->cnf.enhanced_dad ||
3917 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3918 		do
3919 			get_random_bytes(&nonce, 6);
3920 		while (nonce == 0);
3921 	}
3922 	ifp->dad_nonce = nonce;
3923 	ifp->dad_probes = idev->cnf.dad_transmits;
3924 	addrconf_mod_dad_work(ifp, rand_num);
3925 }
3926 
3927 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3928 {
3929 	struct inet6_dev *idev = ifp->idev;
3930 	struct net_device *dev = idev->dev;
3931 	bool bump_id, notify = false;
3932 	struct net *net;
3933 
3934 	addrconf_join_solict(dev, &ifp->addr);
3935 
3936 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3937 
3938 	read_lock_bh(&idev->lock);
3939 	spin_lock(&ifp->lock);
3940 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3941 		goto out;
3942 
3943 	net = dev_net(dev);
3944 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3945 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3946 	     idev->cnf.accept_dad < 1) ||
3947 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3948 	    ifp->flags & IFA_F_NODAD) {
3949 		bool send_na = false;
3950 
3951 		if (ifp->flags & IFA_F_TENTATIVE &&
3952 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3953 			send_na = true;
3954 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3955 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3956 		spin_unlock(&ifp->lock);
3957 		read_unlock_bh(&idev->lock);
3958 
3959 		addrconf_dad_completed(ifp, bump_id, send_na);
3960 		return;
3961 	}
3962 
3963 	if (!(idev->if_flags & IF_READY)) {
3964 		spin_unlock(&ifp->lock);
3965 		read_unlock_bh(&idev->lock);
3966 		/*
3967 		 * If the device is not ready:
3968 		 * - keep it tentative if it is a permanent address.
3969 		 * - otherwise, kill it.
3970 		 */
3971 		in6_ifa_hold(ifp);
3972 		addrconf_dad_stop(ifp, 0);
3973 		return;
3974 	}
3975 
3976 	/*
3977 	 * Optimistic nodes can start receiving
3978 	 * Frames right away
3979 	 */
3980 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3981 		ip6_ins_rt(net, ifp->rt);
3982 		if (ipv6_use_optimistic_addr(net, idev)) {
3983 			/* Because optimistic nodes can use this address,
3984 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3985 			 */
3986 			notify = true;
3987 		}
3988 	}
3989 
3990 	addrconf_dad_kick(ifp);
3991 out:
3992 	spin_unlock(&ifp->lock);
3993 	read_unlock_bh(&idev->lock);
3994 	if (notify)
3995 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3996 }
3997 
3998 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3999 {
4000 	bool begin_dad = false;
4001 
4002 	spin_lock_bh(&ifp->lock);
4003 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4004 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4005 		begin_dad = true;
4006 	}
4007 	spin_unlock_bh(&ifp->lock);
4008 
4009 	if (begin_dad)
4010 		addrconf_mod_dad_work(ifp, 0);
4011 }
4012 
4013 static void addrconf_dad_work(struct work_struct *w)
4014 {
4015 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4016 						struct inet6_ifaddr,
4017 						dad_work);
4018 	struct inet6_dev *idev = ifp->idev;
4019 	bool bump_id, disable_ipv6 = false;
4020 	struct in6_addr mcaddr;
4021 
4022 	enum {
4023 		DAD_PROCESS,
4024 		DAD_BEGIN,
4025 		DAD_ABORT,
4026 	} action = DAD_PROCESS;
4027 
4028 	rtnl_lock();
4029 
4030 	spin_lock_bh(&ifp->lock);
4031 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4032 		action = DAD_BEGIN;
4033 		ifp->state = INET6_IFADDR_STATE_DAD;
4034 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4035 		action = DAD_ABORT;
4036 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4037 
4038 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4039 		     idev->cnf.accept_dad > 1) &&
4040 		    !idev->cnf.disable_ipv6 &&
4041 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4042 			struct in6_addr addr;
4043 
4044 			addr.s6_addr32[0] = htonl(0xfe800000);
4045 			addr.s6_addr32[1] = 0;
4046 
4047 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4048 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4049 				/* DAD failed for link-local based on MAC */
4050 				idev->cnf.disable_ipv6 = 1;
4051 
4052 				pr_info("%s: IPv6 being disabled!\n",
4053 					ifp->idev->dev->name);
4054 				disable_ipv6 = true;
4055 			}
4056 		}
4057 	}
4058 	spin_unlock_bh(&ifp->lock);
4059 
4060 	if (action == DAD_BEGIN) {
4061 		addrconf_dad_begin(ifp);
4062 		goto out;
4063 	} else if (action == DAD_ABORT) {
4064 		in6_ifa_hold(ifp);
4065 		addrconf_dad_stop(ifp, 1);
4066 		if (disable_ipv6)
4067 			addrconf_ifdown(idev->dev, false);
4068 		goto out;
4069 	}
4070 
4071 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4072 		goto out;
4073 
4074 	write_lock_bh(&idev->lock);
4075 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4076 		write_unlock_bh(&idev->lock);
4077 		goto out;
4078 	}
4079 
4080 	spin_lock(&ifp->lock);
4081 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4082 		spin_unlock(&ifp->lock);
4083 		write_unlock_bh(&idev->lock);
4084 		goto out;
4085 	}
4086 
4087 	if (ifp->dad_probes == 0) {
4088 		bool send_na = false;
4089 
4090 		/*
4091 		 * DAD was successful
4092 		 */
4093 
4094 		if (ifp->flags & IFA_F_TENTATIVE &&
4095 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4096 			send_na = true;
4097 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4098 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4099 		spin_unlock(&ifp->lock);
4100 		write_unlock_bh(&idev->lock);
4101 
4102 		addrconf_dad_completed(ifp, bump_id, send_na);
4103 
4104 		goto out;
4105 	}
4106 
4107 	ifp->dad_probes--;
4108 	addrconf_mod_dad_work(ifp,
4109 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4110 				  HZ/100));
4111 	spin_unlock(&ifp->lock);
4112 	write_unlock_bh(&idev->lock);
4113 
4114 	/* send a neighbour solicitation for our addr */
4115 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4116 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4117 		      ifp->dad_nonce);
4118 out:
4119 	in6_ifa_put(ifp);
4120 	rtnl_unlock();
4121 }
4122 
4123 /* ifp->idev must be at least read locked */
4124 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4125 {
4126 	struct inet6_ifaddr *ifpiter;
4127 	struct inet6_dev *idev = ifp->idev;
4128 
4129 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4130 		if (ifpiter->scope > IFA_LINK)
4131 			break;
4132 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4133 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4134 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4135 		    IFA_F_PERMANENT)
4136 			return false;
4137 	}
4138 	return true;
4139 }
4140 
4141 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4142 				   bool send_na)
4143 {
4144 	struct net_device *dev = ifp->idev->dev;
4145 	struct in6_addr lladdr;
4146 	bool send_rs, send_mld;
4147 
4148 	addrconf_del_dad_work(ifp);
4149 
4150 	/*
4151 	 *	Configure the address for reception. Now it is valid.
4152 	 */
4153 
4154 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4155 
4156 	/* If added prefix is link local and we are prepared to process
4157 	   router advertisements, start sending router solicitations.
4158 	 */
4159 
4160 	read_lock_bh(&ifp->idev->lock);
4161 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4162 	send_rs = send_mld &&
4163 		  ipv6_accept_ra(ifp->idev) &&
4164 		  ifp->idev->cnf.rtr_solicits != 0 &&
4165 		  (dev->flags&IFF_LOOPBACK) == 0;
4166 	read_unlock_bh(&ifp->idev->lock);
4167 
4168 	/* While dad is in progress mld report's source address is in6_addrany.
4169 	 * Resend with proper ll now.
4170 	 */
4171 	if (send_mld)
4172 		ipv6_mc_dad_complete(ifp->idev);
4173 
4174 	/* send unsolicited NA if enabled */
4175 	if (send_na &&
4176 	    (ifp->idev->cnf.ndisc_notify ||
4177 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4178 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4179 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4180 			      /*solicited=*/ false, /*override=*/ true,
4181 			      /*inc_opt=*/ true);
4182 	}
4183 
4184 	if (send_rs) {
4185 		/*
4186 		 *	If a host as already performed a random delay
4187 		 *	[...] as part of DAD [...] there is no need
4188 		 *	to delay again before sending the first RS
4189 		 */
4190 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4191 			return;
4192 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4193 
4194 		write_lock_bh(&ifp->idev->lock);
4195 		spin_lock(&ifp->lock);
4196 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4197 			ifp->idev->cnf.rtr_solicit_interval);
4198 		ifp->idev->rs_probes = 1;
4199 		ifp->idev->if_flags |= IF_RS_SENT;
4200 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4201 		spin_unlock(&ifp->lock);
4202 		write_unlock_bh(&ifp->idev->lock);
4203 	}
4204 
4205 	if (bump_id)
4206 		rt_genid_bump_ipv6(dev_net(dev));
4207 
4208 	/* Make sure that a new temporary address will be created
4209 	 * before this temporary address becomes deprecated.
4210 	 */
4211 	if (ifp->flags & IFA_F_TEMPORARY)
4212 		addrconf_verify_rtnl();
4213 }
4214 
4215 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4216 {
4217 	struct inet6_ifaddr *ifp;
4218 
4219 	read_lock_bh(&idev->lock);
4220 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4221 		spin_lock(&ifp->lock);
4222 		if ((ifp->flags & IFA_F_TENTATIVE &&
4223 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4224 			if (restart)
4225 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4226 			addrconf_dad_kick(ifp);
4227 		}
4228 		spin_unlock(&ifp->lock);
4229 	}
4230 	read_unlock_bh(&idev->lock);
4231 }
4232 
4233 #ifdef CONFIG_PROC_FS
4234 struct if6_iter_state {
4235 	struct seq_net_private p;
4236 	int bucket;
4237 	int offset;
4238 };
4239 
4240 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4241 {
4242 	struct if6_iter_state *state = seq->private;
4243 	struct net *net = seq_file_net(seq);
4244 	struct inet6_ifaddr *ifa = NULL;
4245 	int p = 0;
4246 
4247 	/* initial bucket if pos is 0 */
4248 	if (pos == 0) {
4249 		state->bucket = 0;
4250 		state->offset = 0;
4251 	}
4252 
4253 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4254 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4255 					 addr_lst) {
4256 			if (!net_eq(dev_net(ifa->idev->dev), net))
4257 				continue;
4258 			/* sync with offset */
4259 			if (p < state->offset) {
4260 				p++;
4261 				continue;
4262 			}
4263 			return ifa;
4264 		}
4265 
4266 		/* prepare for next bucket */
4267 		state->offset = 0;
4268 		p = 0;
4269 	}
4270 	return NULL;
4271 }
4272 
4273 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4274 					 struct inet6_ifaddr *ifa)
4275 {
4276 	struct if6_iter_state *state = seq->private;
4277 	struct net *net = seq_file_net(seq);
4278 
4279 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4280 		if (!net_eq(dev_net(ifa->idev->dev), net))
4281 			continue;
4282 		state->offset++;
4283 		return ifa;
4284 	}
4285 
4286 	state->offset = 0;
4287 	while (++state->bucket < IN6_ADDR_HSIZE) {
4288 		hlist_for_each_entry_rcu(ifa,
4289 				     &inet6_addr_lst[state->bucket], addr_lst) {
4290 			if (!net_eq(dev_net(ifa->idev->dev), net))
4291 				continue;
4292 			return ifa;
4293 		}
4294 	}
4295 
4296 	return NULL;
4297 }
4298 
4299 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4300 	__acquires(rcu)
4301 {
4302 	rcu_read_lock();
4303 	return if6_get_first(seq, *pos);
4304 }
4305 
4306 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4307 {
4308 	struct inet6_ifaddr *ifa;
4309 
4310 	ifa = if6_get_next(seq, v);
4311 	++*pos;
4312 	return ifa;
4313 }
4314 
4315 static void if6_seq_stop(struct seq_file *seq, void *v)
4316 	__releases(rcu)
4317 {
4318 	rcu_read_unlock();
4319 }
4320 
4321 static int if6_seq_show(struct seq_file *seq, void *v)
4322 {
4323 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4324 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4325 		   &ifp->addr,
4326 		   ifp->idev->dev->ifindex,
4327 		   ifp->prefix_len,
4328 		   ifp->scope,
4329 		   (u8) ifp->flags,
4330 		   ifp->idev->dev->name);
4331 	return 0;
4332 }
4333 
4334 static const struct seq_operations if6_seq_ops = {
4335 	.start	= if6_seq_start,
4336 	.next	= if6_seq_next,
4337 	.show	= if6_seq_show,
4338 	.stop	= if6_seq_stop,
4339 };
4340 
4341 static int __net_init if6_proc_net_init(struct net *net)
4342 {
4343 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4344 			sizeof(struct if6_iter_state)))
4345 		return -ENOMEM;
4346 	return 0;
4347 }
4348 
4349 static void __net_exit if6_proc_net_exit(struct net *net)
4350 {
4351 	remove_proc_entry("if_inet6", net->proc_net);
4352 }
4353 
4354 static struct pernet_operations if6_proc_net_ops = {
4355 	.init = if6_proc_net_init,
4356 	.exit = if6_proc_net_exit,
4357 };
4358 
4359 int __init if6_proc_init(void)
4360 {
4361 	return register_pernet_subsys(&if6_proc_net_ops);
4362 }
4363 
4364 void if6_proc_exit(void)
4365 {
4366 	unregister_pernet_subsys(&if6_proc_net_ops);
4367 }
4368 #endif	/* CONFIG_PROC_FS */
4369 
4370 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4371 /* Check if address is a home address configured on any interface. */
4372 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4373 {
4374 	unsigned int hash = inet6_addr_hash(net, addr);
4375 	struct inet6_ifaddr *ifp = NULL;
4376 	int ret = 0;
4377 
4378 	rcu_read_lock();
4379 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4380 		if (!net_eq(dev_net(ifp->idev->dev), net))
4381 			continue;
4382 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4383 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4384 			ret = 1;
4385 			break;
4386 		}
4387 	}
4388 	rcu_read_unlock();
4389 	return ret;
4390 }
4391 #endif
4392 
4393 /* RFC6554 has some algorithm to avoid loops in segment routing by
4394  * checking if the segments contains any of a local interface address.
4395  *
4396  * Quote:
4397  *
4398  * To detect loops in the SRH, a router MUST determine if the SRH
4399  * includes multiple addresses assigned to any interface on that router.
4400  * If such addresses appear more than once and are separated by at least
4401  * one address not assigned to that router.
4402  */
4403 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4404 			  unsigned char nsegs)
4405 {
4406 	const struct in6_addr *addr;
4407 	int i, ret = 0, found = 0;
4408 	struct inet6_ifaddr *ifp;
4409 	bool separated = false;
4410 	unsigned int hash;
4411 	bool hash_found;
4412 
4413 	rcu_read_lock();
4414 	for (i = 0; i < nsegs; i++) {
4415 		addr = &segs[i];
4416 		hash = inet6_addr_hash(net, addr);
4417 
4418 		hash_found = false;
4419 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4420 			if (!net_eq(dev_net(ifp->idev->dev), net))
4421 				continue;
4422 
4423 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4424 				hash_found = true;
4425 				break;
4426 			}
4427 		}
4428 
4429 		if (hash_found) {
4430 			if (found > 1 && separated) {
4431 				ret = 1;
4432 				break;
4433 			}
4434 
4435 			separated = false;
4436 			found++;
4437 		} else {
4438 			separated = true;
4439 		}
4440 	}
4441 	rcu_read_unlock();
4442 
4443 	return ret;
4444 }
4445 
4446 /*
4447  *	Periodic address status verification
4448  */
4449 
4450 static void addrconf_verify_rtnl(void)
4451 {
4452 	unsigned long now, next, next_sec, next_sched;
4453 	struct inet6_ifaddr *ifp;
4454 	int i;
4455 
4456 	ASSERT_RTNL();
4457 
4458 	rcu_read_lock_bh();
4459 	now = jiffies;
4460 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4461 
4462 	cancel_delayed_work(&addr_chk_work);
4463 
4464 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4465 restart:
4466 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4467 			unsigned long age;
4468 
4469 			/* When setting preferred_lft to a value not zero or
4470 			 * infinity, while valid_lft is infinity
4471 			 * IFA_F_PERMANENT has a non-infinity life time.
4472 			 */
4473 			if ((ifp->flags & IFA_F_PERMANENT) &&
4474 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4475 				continue;
4476 
4477 			spin_lock(&ifp->lock);
4478 			/* We try to batch several events at once. */
4479 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4480 
4481 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4482 			    age >= ifp->valid_lft) {
4483 				spin_unlock(&ifp->lock);
4484 				in6_ifa_hold(ifp);
4485 				ipv6_del_addr(ifp);
4486 				goto restart;
4487 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4488 				spin_unlock(&ifp->lock);
4489 				continue;
4490 			} else if (age >= ifp->prefered_lft) {
4491 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4492 				int deprecate = 0;
4493 
4494 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4495 					deprecate = 1;
4496 					ifp->flags |= IFA_F_DEPRECATED;
4497 				}
4498 
4499 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4500 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4501 					next = ifp->tstamp + ifp->valid_lft * HZ;
4502 
4503 				spin_unlock(&ifp->lock);
4504 
4505 				if (deprecate) {
4506 					in6_ifa_hold(ifp);
4507 
4508 					ipv6_ifa_notify(0, ifp);
4509 					in6_ifa_put(ifp);
4510 					goto restart;
4511 				}
4512 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4513 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4514 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4515 					ifp->idev->cnf.dad_transmits *
4516 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4517 
4518 				if (age >= ifp->prefered_lft - regen_advance) {
4519 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4520 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4521 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4522 					if (!ifp->regen_count && ifpub) {
4523 						ifp->regen_count++;
4524 						in6_ifa_hold(ifp);
4525 						in6_ifa_hold(ifpub);
4526 						spin_unlock(&ifp->lock);
4527 
4528 						spin_lock(&ifpub->lock);
4529 						ifpub->regen_count = 0;
4530 						spin_unlock(&ifpub->lock);
4531 						rcu_read_unlock_bh();
4532 						ipv6_create_tempaddr(ifpub, true);
4533 						in6_ifa_put(ifpub);
4534 						in6_ifa_put(ifp);
4535 						rcu_read_lock_bh();
4536 						goto restart;
4537 					}
4538 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4539 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4540 				spin_unlock(&ifp->lock);
4541 			} else {
4542 				/* ifp->prefered_lft <= ifp->valid_lft */
4543 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4544 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4545 				spin_unlock(&ifp->lock);
4546 			}
4547 		}
4548 	}
4549 
4550 	next_sec = round_jiffies_up(next);
4551 	next_sched = next;
4552 
4553 	/* If rounded timeout is accurate enough, accept it. */
4554 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4555 		next_sched = next_sec;
4556 
4557 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4558 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4559 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4560 
4561 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4562 		 now, next, next_sec, next_sched);
4563 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4564 	rcu_read_unlock_bh();
4565 }
4566 
4567 static void addrconf_verify_work(struct work_struct *w)
4568 {
4569 	rtnl_lock();
4570 	addrconf_verify_rtnl();
4571 	rtnl_unlock();
4572 }
4573 
4574 static void addrconf_verify(void)
4575 {
4576 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4577 }
4578 
4579 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4580 				     struct in6_addr **peer_pfx)
4581 {
4582 	struct in6_addr *pfx = NULL;
4583 
4584 	*peer_pfx = NULL;
4585 
4586 	if (addr)
4587 		pfx = nla_data(addr);
4588 
4589 	if (local) {
4590 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4591 			*peer_pfx = pfx;
4592 		pfx = nla_data(local);
4593 	}
4594 
4595 	return pfx;
4596 }
4597 
4598 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4599 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4600 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4601 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4602 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4603 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4604 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4605 };
4606 
4607 static int
4608 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4609 		  struct netlink_ext_ack *extack)
4610 {
4611 	struct net *net = sock_net(skb->sk);
4612 	struct ifaddrmsg *ifm;
4613 	struct nlattr *tb[IFA_MAX+1];
4614 	struct in6_addr *pfx, *peer_pfx;
4615 	u32 ifa_flags;
4616 	int err;
4617 
4618 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4619 				     ifa_ipv6_policy, extack);
4620 	if (err < 0)
4621 		return err;
4622 
4623 	ifm = nlmsg_data(nlh);
4624 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4625 	if (!pfx)
4626 		return -EINVAL;
4627 
4628 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4629 
4630 	/* We ignore other flags so far. */
4631 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4632 
4633 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4634 			      ifm->ifa_prefixlen);
4635 }
4636 
4637 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4638 			       unsigned long expires, u32 flags,
4639 			       bool modify_peer)
4640 {
4641 	struct fib6_info *f6i;
4642 	u32 prio;
4643 
4644 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4645 					ifp->prefix_len,
4646 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4647 	if (!f6i)
4648 		return -ENOENT;
4649 
4650 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4651 	if (f6i->fib6_metric != prio) {
4652 		/* delete old one */
4653 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4654 
4655 		/* add new one */
4656 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4657 				      ifp->prefix_len,
4658 				      ifp->rt_priority, ifp->idev->dev,
4659 				      expires, flags, GFP_KERNEL);
4660 	} else {
4661 		if (!expires)
4662 			fib6_clean_expires(f6i);
4663 		else
4664 			fib6_set_expires(f6i, expires);
4665 
4666 		fib6_info_release(f6i);
4667 	}
4668 
4669 	return 0;
4670 }
4671 
4672 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4673 {
4674 	u32 flags;
4675 	clock_t expires;
4676 	unsigned long timeout;
4677 	bool was_managetempaddr;
4678 	bool had_prefixroute;
4679 	bool new_peer = false;
4680 
4681 	ASSERT_RTNL();
4682 
4683 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4684 		return -EINVAL;
4685 
4686 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4687 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4688 		return -EINVAL;
4689 
4690 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4691 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4692 
4693 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4694 	if (addrconf_finite_timeout(timeout)) {
4695 		expires = jiffies_to_clock_t(timeout * HZ);
4696 		cfg->valid_lft = timeout;
4697 		flags = RTF_EXPIRES;
4698 	} else {
4699 		expires = 0;
4700 		flags = 0;
4701 		cfg->ifa_flags |= IFA_F_PERMANENT;
4702 	}
4703 
4704 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4705 	if (addrconf_finite_timeout(timeout)) {
4706 		if (timeout == 0)
4707 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4708 		cfg->preferred_lft = timeout;
4709 	}
4710 
4711 	if (cfg->peer_pfx &&
4712 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4713 		if (!ipv6_addr_any(&ifp->peer_addr))
4714 			cleanup_prefix_route(ifp, expires, true, true);
4715 		new_peer = true;
4716 	}
4717 
4718 	spin_lock_bh(&ifp->lock);
4719 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4720 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4721 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4722 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4723 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4724 			IFA_F_NOPREFIXROUTE);
4725 	ifp->flags |= cfg->ifa_flags;
4726 	ifp->tstamp = jiffies;
4727 	ifp->valid_lft = cfg->valid_lft;
4728 	ifp->prefered_lft = cfg->preferred_lft;
4729 
4730 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4731 		ifp->rt_priority = cfg->rt_priority;
4732 
4733 	if (new_peer)
4734 		ifp->peer_addr = *cfg->peer_pfx;
4735 
4736 	spin_unlock_bh(&ifp->lock);
4737 	if (!(ifp->flags&IFA_F_TENTATIVE))
4738 		ipv6_ifa_notify(0, ifp);
4739 
4740 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4741 		int rc = -ENOENT;
4742 
4743 		if (had_prefixroute)
4744 			rc = modify_prefix_route(ifp, expires, flags, false);
4745 
4746 		/* prefix route could have been deleted; if so restore it */
4747 		if (rc == -ENOENT) {
4748 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4749 					      ifp->rt_priority, ifp->idev->dev,
4750 					      expires, flags, GFP_KERNEL);
4751 		}
4752 
4753 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4754 			rc = modify_prefix_route(ifp, expires, flags, true);
4755 
4756 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4757 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4758 					      ifp->rt_priority, ifp->idev->dev,
4759 					      expires, flags, GFP_KERNEL);
4760 		}
4761 	} else if (had_prefixroute) {
4762 		enum cleanup_prefix_rt_t action;
4763 		unsigned long rt_expires;
4764 
4765 		write_lock_bh(&ifp->idev->lock);
4766 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4767 		write_unlock_bh(&ifp->idev->lock);
4768 
4769 		if (action != CLEANUP_PREFIX_RT_NOP) {
4770 			cleanup_prefix_route(ifp, rt_expires,
4771 				action == CLEANUP_PREFIX_RT_DEL, false);
4772 		}
4773 	}
4774 
4775 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4776 		if (was_managetempaddr &&
4777 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4778 			cfg->valid_lft = 0;
4779 			cfg->preferred_lft = 0;
4780 		}
4781 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4782 				 cfg->preferred_lft, !was_managetempaddr,
4783 				 jiffies);
4784 	}
4785 
4786 	addrconf_verify_rtnl();
4787 
4788 	return 0;
4789 }
4790 
4791 static int
4792 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4793 		  struct netlink_ext_ack *extack)
4794 {
4795 	struct net *net = sock_net(skb->sk);
4796 	struct ifaddrmsg *ifm;
4797 	struct nlattr *tb[IFA_MAX+1];
4798 	struct in6_addr *peer_pfx;
4799 	struct inet6_ifaddr *ifa;
4800 	struct net_device *dev;
4801 	struct inet6_dev *idev;
4802 	struct ifa6_config cfg;
4803 	int err;
4804 
4805 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4806 				     ifa_ipv6_policy, extack);
4807 	if (err < 0)
4808 		return err;
4809 
4810 	memset(&cfg, 0, sizeof(cfg));
4811 
4812 	ifm = nlmsg_data(nlh);
4813 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4814 	if (!cfg.pfx)
4815 		return -EINVAL;
4816 
4817 	cfg.peer_pfx = peer_pfx;
4818 	cfg.plen = ifm->ifa_prefixlen;
4819 	if (tb[IFA_RT_PRIORITY])
4820 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4821 
4822 	cfg.valid_lft = INFINITY_LIFE_TIME;
4823 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4824 
4825 	if (tb[IFA_CACHEINFO]) {
4826 		struct ifa_cacheinfo *ci;
4827 
4828 		ci = nla_data(tb[IFA_CACHEINFO]);
4829 		cfg.valid_lft = ci->ifa_valid;
4830 		cfg.preferred_lft = ci->ifa_prefered;
4831 	}
4832 
4833 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4834 	if (!dev)
4835 		return -ENODEV;
4836 
4837 	if (tb[IFA_FLAGS])
4838 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4839 	else
4840 		cfg.ifa_flags = ifm->ifa_flags;
4841 
4842 	/* We ignore other flags so far. */
4843 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4844 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4845 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4846 
4847 	idev = ipv6_find_idev(dev);
4848 	if (IS_ERR(idev))
4849 		return PTR_ERR(idev);
4850 
4851 	if (!ipv6_allow_optimistic_dad(net, idev))
4852 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4853 
4854 	if (cfg.ifa_flags & IFA_F_NODAD &&
4855 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4856 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4857 		return -EINVAL;
4858 	}
4859 
4860 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4861 	if (!ifa) {
4862 		/*
4863 		 * It would be best to check for !NLM_F_CREATE here but
4864 		 * userspace already relies on not having to provide this.
4865 		 */
4866 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4867 	}
4868 
4869 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4870 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4871 		err = -EEXIST;
4872 	else
4873 		err = inet6_addr_modify(ifa, &cfg);
4874 
4875 	in6_ifa_put(ifa);
4876 
4877 	return err;
4878 }
4879 
4880 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4881 			  u8 scope, int ifindex)
4882 {
4883 	struct ifaddrmsg *ifm;
4884 
4885 	ifm = nlmsg_data(nlh);
4886 	ifm->ifa_family = AF_INET6;
4887 	ifm->ifa_prefixlen = prefixlen;
4888 	ifm->ifa_flags = flags;
4889 	ifm->ifa_scope = scope;
4890 	ifm->ifa_index = ifindex;
4891 }
4892 
4893 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4894 			 unsigned long tstamp, u32 preferred, u32 valid)
4895 {
4896 	struct ifa_cacheinfo ci;
4897 
4898 	ci.cstamp = cstamp_delta(cstamp);
4899 	ci.tstamp = cstamp_delta(tstamp);
4900 	ci.ifa_prefered = preferred;
4901 	ci.ifa_valid = valid;
4902 
4903 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4904 }
4905 
4906 static inline int rt_scope(int ifa_scope)
4907 {
4908 	if (ifa_scope & IFA_HOST)
4909 		return RT_SCOPE_HOST;
4910 	else if (ifa_scope & IFA_LINK)
4911 		return RT_SCOPE_LINK;
4912 	else if (ifa_scope & IFA_SITE)
4913 		return RT_SCOPE_SITE;
4914 	else
4915 		return RT_SCOPE_UNIVERSE;
4916 }
4917 
4918 static inline int inet6_ifaddr_msgsize(void)
4919 {
4920 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4921 	       + nla_total_size(16) /* IFA_LOCAL */
4922 	       + nla_total_size(16) /* IFA_ADDRESS */
4923 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4924 	       + nla_total_size(4)  /* IFA_FLAGS */
4925 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4926 }
4927 
4928 enum addr_type_t {
4929 	UNICAST_ADDR,
4930 	MULTICAST_ADDR,
4931 	ANYCAST_ADDR,
4932 };
4933 
4934 struct inet6_fill_args {
4935 	u32 portid;
4936 	u32 seq;
4937 	int event;
4938 	unsigned int flags;
4939 	int netnsid;
4940 	int ifindex;
4941 	enum addr_type_t type;
4942 };
4943 
4944 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4945 			     struct inet6_fill_args *args)
4946 {
4947 	struct nlmsghdr  *nlh;
4948 	u32 preferred, valid;
4949 
4950 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4951 			sizeof(struct ifaddrmsg), args->flags);
4952 	if (!nlh)
4953 		return -EMSGSIZE;
4954 
4955 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4956 		      ifa->idev->dev->ifindex);
4957 
4958 	if (args->netnsid >= 0 &&
4959 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4960 		goto error;
4961 
4962 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4963 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4964 		preferred = ifa->prefered_lft;
4965 		valid = ifa->valid_lft;
4966 		if (preferred != INFINITY_LIFE_TIME) {
4967 			long tval = (jiffies - ifa->tstamp)/HZ;
4968 			if (preferred > tval)
4969 				preferred -= tval;
4970 			else
4971 				preferred = 0;
4972 			if (valid != INFINITY_LIFE_TIME) {
4973 				if (valid > tval)
4974 					valid -= tval;
4975 				else
4976 					valid = 0;
4977 			}
4978 		}
4979 	} else {
4980 		preferred = INFINITY_LIFE_TIME;
4981 		valid = INFINITY_LIFE_TIME;
4982 	}
4983 
4984 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4985 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4986 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4987 			goto error;
4988 	} else
4989 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4990 			goto error;
4991 
4992 	if (ifa->rt_priority &&
4993 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4994 		goto error;
4995 
4996 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4997 		goto error;
4998 
4999 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5000 		goto error;
5001 
5002 	nlmsg_end(skb, nlh);
5003 	return 0;
5004 
5005 error:
5006 	nlmsg_cancel(skb, nlh);
5007 	return -EMSGSIZE;
5008 }
5009 
5010 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5011 			       struct inet6_fill_args *args)
5012 {
5013 	struct nlmsghdr  *nlh;
5014 	u8 scope = RT_SCOPE_UNIVERSE;
5015 	int ifindex = ifmca->idev->dev->ifindex;
5016 
5017 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5018 		scope = RT_SCOPE_SITE;
5019 
5020 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5021 			sizeof(struct ifaddrmsg), args->flags);
5022 	if (!nlh)
5023 		return -EMSGSIZE;
5024 
5025 	if (args->netnsid >= 0 &&
5026 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5027 		return -EMSGSIZE;
5028 
5029 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5030 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5031 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5032 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5033 		nlmsg_cancel(skb, nlh);
5034 		return -EMSGSIZE;
5035 	}
5036 
5037 	nlmsg_end(skb, nlh);
5038 	return 0;
5039 }
5040 
5041 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5042 			       struct inet6_fill_args *args)
5043 {
5044 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5045 	int ifindex = dev ? dev->ifindex : 1;
5046 	struct nlmsghdr  *nlh;
5047 	u8 scope = RT_SCOPE_UNIVERSE;
5048 
5049 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5050 		scope = RT_SCOPE_SITE;
5051 
5052 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5053 			sizeof(struct ifaddrmsg), args->flags);
5054 	if (!nlh)
5055 		return -EMSGSIZE;
5056 
5057 	if (args->netnsid >= 0 &&
5058 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5059 		return -EMSGSIZE;
5060 
5061 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5062 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5063 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5064 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5065 		nlmsg_cancel(skb, nlh);
5066 		return -EMSGSIZE;
5067 	}
5068 
5069 	nlmsg_end(skb, nlh);
5070 	return 0;
5071 }
5072 
5073 /* called with rcu_read_lock() */
5074 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5075 			  struct netlink_callback *cb, int s_ip_idx,
5076 			  struct inet6_fill_args *fillargs)
5077 {
5078 	struct ifmcaddr6 *ifmca;
5079 	struct ifacaddr6 *ifaca;
5080 	int ip_idx = 0;
5081 	int err = 1;
5082 
5083 	read_lock_bh(&idev->lock);
5084 	switch (fillargs->type) {
5085 	case UNICAST_ADDR: {
5086 		struct inet6_ifaddr *ifa;
5087 		fillargs->event = RTM_NEWADDR;
5088 
5089 		/* unicast address incl. temp addr */
5090 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5091 			if (ip_idx < s_ip_idx)
5092 				goto next;
5093 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5094 			if (err < 0)
5095 				break;
5096 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5097 next:
5098 			ip_idx++;
5099 		}
5100 		break;
5101 	}
5102 	case MULTICAST_ADDR:
5103 		fillargs->event = RTM_GETMULTICAST;
5104 
5105 		/* multicast address */
5106 		for (ifmca = idev->mc_list; ifmca;
5107 		     ifmca = ifmca->next, ip_idx++) {
5108 			if (ip_idx < s_ip_idx)
5109 				continue;
5110 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5111 			if (err < 0)
5112 				break;
5113 		}
5114 		break;
5115 	case ANYCAST_ADDR:
5116 		fillargs->event = RTM_GETANYCAST;
5117 		/* anycast address */
5118 		for (ifaca = idev->ac_list; ifaca;
5119 		     ifaca = ifaca->aca_next, ip_idx++) {
5120 			if (ip_idx < s_ip_idx)
5121 				continue;
5122 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5123 			if (err < 0)
5124 				break;
5125 		}
5126 		break;
5127 	default:
5128 		break;
5129 	}
5130 	read_unlock_bh(&idev->lock);
5131 	cb->args[2] = ip_idx;
5132 	return err;
5133 }
5134 
5135 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5136 				       struct inet6_fill_args *fillargs,
5137 				       struct net **tgt_net, struct sock *sk,
5138 				       struct netlink_callback *cb)
5139 {
5140 	struct netlink_ext_ack *extack = cb->extack;
5141 	struct nlattr *tb[IFA_MAX+1];
5142 	struct ifaddrmsg *ifm;
5143 	int err, i;
5144 
5145 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5146 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5147 		return -EINVAL;
5148 	}
5149 
5150 	ifm = nlmsg_data(nlh);
5151 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5152 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5153 		return -EINVAL;
5154 	}
5155 
5156 	fillargs->ifindex = ifm->ifa_index;
5157 	if (fillargs->ifindex) {
5158 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5159 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5160 	}
5161 
5162 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5163 					    ifa_ipv6_policy, extack);
5164 	if (err < 0)
5165 		return err;
5166 
5167 	for (i = 0; i <= IFA_MAX; ++i) {
5168 		if (!tb[i])
5169 			continue;
5170 
5171 		if (i == IFA_TARGET_NETNSID) {
5172 			struct net *net;
5173 
5174 			fillargs->netnsid = nla_get_s32(tb[i]);
5175 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5176 			if (IS_ERR(net)) {
5177 				fillargs->netnsid = -1;
5178 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5179 				return PTR_ERR(net);
5180 			}
5181 			*tgt_net = net;
5182 		} else {
5183 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5184 			return -EINVAL;
5185 		}
5186 	}
5187 
5188 	return 0;
5189 }
5190 
5191 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5192 			   enum addr_type_t type)
5193 {
5194 	const struct nlmsghdr *nlh = cb->nlh;
5195 	struct inet6_fill_args fillargs = {
5196 		.portid = NETLINK_CB(cb->skb).portid,
5197 		.seq = cb->nlh->nlmsg_seq,
5198 		.flags = NLM_F_MULTI,
5199 		.netnsid = -1,
5200 		.type = type,
5201 	};
5202 	struct net *net = sock_net(skb->sk);
5203 	struct net *tgt_net = net;
5204 	int idx, s_idx, s_ip_idx;
5205 	int h, s_h;
5206 	struct net_device *dev;
5207 	struct inet6_dev *idev;
5208 	struct hlist_head *head;
5209 	int err = 0;
5210 
5211 	s_h = cb->args[0];
5212 	s_idx = idx = cb->args[1];
5213 	s_ip_idx = cb->args[2];
5214 
5215 	if (cb->strict_check) {
5216 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5217 						  skb->sk, cb);
5218 		if (err < 0)
5219 			goto put_tgt_net;
5220 
5221 		err = 0;
5222 		if (fillargs.ifindex) {
5223 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5224 			if (!dev) {
5225 				err = -ENODEV;
5226 				goto put_tgt_net;
5227 			}
5228 			idev = __in6_dev_get(dev);
5229 			if (idev) {
5230 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5231 						     &fillargs);
5232 				if (err > 0)
5233 					err = 0;
5234 			}
5235 			goto put_tgt_net;
5236 		}
5237 	}
5238 
5239 	rcu_read_lock();
5240 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5241 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5242 		idx = 0;
5243 		head = &tgt_net->dev_index_head[h];
5244 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5245 			if (idx < s_idx)
5246 				goto cont;
5247 			if (h > s_h || idx > s_idx)
5248 				s_ip_idx = 0;
5249 			idev = __in6_dev_get(dev);
5250 			if (!idev)
5251 				goto cont;
5252 
5253 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5254 					   &fillargs) < 0)
5255 				goto done;
5256 cont:
5257 			idx++;
5258 		}
5259 	}
5260 done:
5261 	rcu_read_unlock();
5262 	cb->args[0] = h;
5263 	cb->args[1] = idx;
5264 put_tgt_net:
5265 	if (fillargs.netnsid >= 0)
5266 		put_net(tgt_net);
5267 
5268 	return skb->len ? : err;
5269 }
5270 
5271 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5272 {
5273 	enum addr_type_t type = UNICAST_ADDR;
5274 
5275 	return inet6_dump_addr(skb, cb, type);
5276 }
5277 
5278 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5279 {
5280 	enum addr_type_t type = MULTICAST_ADDR;
5281 
5282 	return inet6_dump_addr(skb, cb, type);
5283 }
5284 
5285 
5286 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5287 {
5288 	enum addr_type_t type = ANYCAST_ADDR;
5289 
5290 	return inet6_dump_addr(skb, cb, type);
5291 }
5292 
5293 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5294 				       const struct nlmsghdr *nlh,
5295 				       struct nlattr **tb,
5296 				       struct netlink_ext_ack *extack)
5297 {
5298 	struct ifaddrmsg *ifm;
5299 	int i, err;
5300 
5301 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5302 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5303 		return -EINVAL;
5304 	}
5305 
5306 	if (!netlink_strict_get_check(skb))
5307 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5308 					      ifa_ipv6_policy, extack);
5309 
5310 	ifm = nlmsg_data(nlh);
5311 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5312 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5313 		return -EINVAL;
5314 	}
5315 
5316 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5317 					    ifa_ipv6_policy, extack);
5318 	if (err)
5319 		return err;
5320 
5321 	for (i = 0; i <= IFA_MAX; i++) {
5322 		if (!tb[i])
5323 			continue;
5324 
5325 		switch (i) {
5326 		case IFA_TARGET_NETNSID:
5327 		case IFA_ADDRESS:
5328 		case IFA_LOCAL:
5329 			break;
5330 		default:
5331 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5332 			return -EINVAL;
5333 		}
5334 	}
5335 
5336 	return 0;
5337 }
5338 
5339 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5340 			     struct netlink_ext_ack *extack)
5341 {
5342 	struct net *net = sock_net(in_skb->sk);
5343 	struct inet6_fill_args fillargs = {
5344 		.portid = NETLINK_CB(in_skb).portid,
5345 		.seq = nlh->nlmsg_seq,
5346 		.event = RTM_NEWADDR,
5347 		.flags = 0,
5348 		.netnsid = -1,
5349 	};
5350 	struct net *tgt_net = net;
5351 	struct ifaddrmsg *ifm;
5352 	struct nlattr *tb[IFA_MAX+1];
5353 	struct in6_addr *addr = NULL, *peer;
5354 	struct net_device *dev = NULL;
5355 	struct inet6_ifaddr *ifa;
5356 	struct sk_buff *skb;
5357 	int err;
5358 
5359 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5360 	if (err < 0)
5361 		return err;
5362 
5363 	if (tb[IFA_TARGET_NETNSID]) {
5364 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5365 
5366 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5367 						  fillargs.netnsid);
5368 		if (IS_ERR(tgt_net))
5369 			return PTR_ERR(tgt_net);
5370 	}
5371 
5372 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5373 	if (!addr)
5374 		return -EINVAL;
5375 
5376 	ifm = nlmsg_data(nlh);
5377 	if (ifm->ifa_index)
5378 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5379 
5380 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5381 	if (!ifa) {
5382 		err = -EADDRNOTAVAIL;
5383 		goto errout;
5384 	}
5385 
5386 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5387 	if (!skb) {
5388 		err = -ENOBUFS;
5389 		goto errout_ifa;
5390 	}
5391 
5392 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5393 	if (err < 0) {
5394 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5395 		WARN_ON(err == -EMSGSIZE);
5396 		kfree_skb(skb);
5397 		goto errout_ifa;
5398 	}
5399 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5400 errout_ifa:
5401 	in6_ifa_put(ifa);
5402 errout:
5403 	if (dev)
5404 		dev_put(dev);
5405 	if (fillargs.netnsid >= 0)
5406 		put_net(tgt_net);
5407 
5408 	return err;
5409 }
5410 
5411 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5412 {
5413 	struct sk_buff *skb;
5414 	struct net *net = dev_net(ifa->idev->dev);
5415 	struct inet6_fill_args fillargs = {
5416 		.portid = 0,
5417 		.seq = 0,
5418 		.event = event,
5419 		.flags = 0,
5420 		.netnsid = -1,
5421 	};
5422 	int err = -ENOBUFS;
5423 
5424 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5425 	if (!skb)
5426 		goto errout;
5427 
5428 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5429 	if (err < 0) {
5430 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5431 		WARN_ON(err == -EMSGSIZE);
5432 		kfree_skb(skb);
5433 		goto errout;
5434 	}
5435 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5436 	return;
5437 errout:
5438 	if (err < 0)
5439 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5440 }
5441 
5442 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5443 				__s32 *array, int bytes)
5444 {
5445 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5446 
5447 	memset(array, 0, bytes);
5448 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5449 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5450 	array[DEVCONF_MTU6] = cnf->mtu6;
5451 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5452 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5453 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5454 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5455 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5456 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5457 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5458 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5459 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5460 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5461 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5462 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5463 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5464 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5465 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5466 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5467 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5468 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5469 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5470 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5471 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5472 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5473 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5474 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5475 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5476 #ifdef CONFIG_IPV6_ROUTER_PREF
5477 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5478 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5479 		jiffies_to_msecs(cnf->rtr_probe_interval);
5480 #ifdef CONFIG_IPV6_ROUTE_INFO
5481 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5482 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5483 #endif
5484 #endif
5485 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5486 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5487 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5488 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5489 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5490 #endif
5491 #ifdef CONFIG_IPV6_MROUTE
5492 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5493 #endif
5494 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5495 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5496 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5497 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5498 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5499 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5500 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5501 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5502 	/* we omit DEVCONF_STABLE_SECRET for now */
5503 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5504 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5505 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5506 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5507 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5508 #ifdef CONFIG_IPV6_SEG6_HMAC
5509 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5510 #endif
5511 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5512 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5513 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5514 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5515 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5516 }
5517 
5518 static inline size_t inet6_ifla6_size(void)
5519 {
5520 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5521 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5522 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5523 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5524 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5525 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5526 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5527 	     + 0;
5528 }
5529 
5530 static inline size_t inet6_if_nlmsg_size(void)
5531 {
5532 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5533 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5534 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5535 	       + nla_total_size(4) /* IFLA_MTU */
5536 	       + nla_total_size(4) /* IFLA_LINK */
5537 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5538 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5539 }
5540 
5541 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5542 					int bytes)
5543 {
5544 	int i;
5545 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5546 	BUG_ON(pad < 0);
5547 
5548 	/* Use put_unaligned() because stats may not be aligned for u64. */
5549 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5550 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5551 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5552 
5553 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5554 }
5555 
5556 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5557 					int bytes, size_t syncpoff)
5558 {
5559 	int i, c;
5560 	u64 buff[IPSTATS_MIB_MAX];
5561 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5562 
5563 	BUG_ON(pad < 0);
5564 
5565 	memset(buff, 0, sizeof(buff));
5566 	buff[0] = IPSTATS_MIB_MAX;
5567 
5568 	for_each_possible_cpu(c) {
5569 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5570 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5571 	}
5572 
5573 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5574 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5575 }
5576 
5577 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5578 			     int bytes)
5579 {
5580 	switch (attrtype) {
5581 	case IFLA_INET6_STATS:
5582 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5583 				     offsetof(struct ipstats_mib, syncp));
5584 		break;
5585 	case IFLA_INET6_ICMP6STATS:
5586 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5587 		break;
5588 	}
5589 }
5590 
5591 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5592 				  u32 ext_filter_mask)
5593 {
5594 	struct nlattr *nla;
5595 	struct ifla_cacheinfo ci;
5596 
5597 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5598 		goto nla_put_failure;
5599 	ci.max_reasm_len = IPV6_MAXPLEN;
5600 	ci.tstamp = cstamp_delta(idev->tstamp);
5601 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5602 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5603 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5604 		goto nla_put_failure;
5605 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5606 	if (!nla)
5607 		goto nla_put_failure;
5608 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5609 
5610 	/* XXX - MC not implemented */
5611 
5612 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5613 		return 0;
5614 
5615 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5616 	if (!nla)
5617 		goto nla_put_failure;
5618 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5619 
5620 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5621 	if (!nla)
5622 		goto nla_put_failure;
5623 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5624 
5625 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5626 	if (!nla)
5627 		goto nla_put_failure;
5628 	read_lock_bh(&idev->lock);
5629 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5630 	read_unlock_bh(&idev->lock);
5631 
5632 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5633 		goto nla_put_failure;
5634 
5635 	return 0;
5636 
5637 nla_put_failure:
5638 	return -EMSGSIZE;
5639 }
5640 
5641 static size_t inet6_get_link_af_size(const struct net_device *dev,
5642 				     u32 ext_filter_mask)
5643 {
5644 	if (!__in6_dev_get(dev))
5645 		return 0;
5646 
5647 	return inet6_ifla6_size();
5648 }
5649 
5650 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5651 			      u32 ext_filter_mask)
5652 {
5653 	struct inet6_dev *idev = __in6_dev_get(dev);
5654 
5655 	if (!idev)
5656 		return -ENODATA;
5657 
5658 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5659 		return -EMSGSIZE;
5660 
5661 	return 0;
5662 }
5663 
5664 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5665 {
5666 	struct inet6_ifaddr *ifp;
5667 	struct net_device *dev = idev->dev;
5668 	bool clear_token, update_rs = false;
5669 	struct in6_addr ll_addr;
5670 
5671 	ASSERT_RTNL();
5672 
5673 	if (!token)
5674 		return -EINVAL;
5675 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5676 		return -EINVAL;
5677 	if (!ipv6_accept_ra(idev))
5678 		return -EINVAL;
5679 	if (idev->cnf.rtr_solicits == 0)
5680 		return -EINVAL;
5681 
5682 	write_lock_bh(&idev->lock);
5683 
5684 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5685 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5686 
5687 	write_unlock_bh(&idev->lock);
5688 
5689 	clear_token = ipv6_addr_any(token);
5690 	if (clear_token)
5691 		goto update_lft;
5692 
5693 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5694 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5695 			     IFA_F_OPTIMISTIC)) {
5696 		/* If we're not ready, then normal ifup will take care
5697 		 * of this. Otherwise, we need to request our rs here.
5698 		 */
5699 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5700 		update_rs = true;
5701 	}
5702 
5703 update_lft:
5704 	write_lock_bh(&idev->lock);
5705 
5706 	if (update_rs) {
5707 		idev->if_flags |= IF_RS_SENT;
5708 		idev->rs_interval = rfc3315_s14_backoff_init(
5709 			idev->cnf.rtr_solicit_interval);
5710 		idev->rs_probes = 1;
5711 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5712 	}
5713 
5714 	/* Well, that's kinda nasty ... */
5715 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5716 		spin_lock(&ifp->lock);
5717 		if (ifp->tokenized) {
5718 			ifp->valid_lft = 0;
5719 			ifp->prefered_lft = 0;
5720 		}
5721 		spin_unlock(&ifp->lock);
5722 	}
5723 
5724 	write_unlock_bh(&idev->lock);
5725 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5726 	addrconf_verify_rtnl();
5727 	return 0;
5728 }
5729 
5730 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5731 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5732 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5733 };
5734 
5735 static int check_addr_gen_mode(int mode)
5736 {
5737 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5738 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5739 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5740 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5741 		return -EINVAL;
5742 	return 1;
5743 }
5744 
5745 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5746 				int mode)
5747 {
5748 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5749 	    !idev->cnf.stable_secret.initialized &&
5750 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5751 		return -EINVAL;
5752 	return 1;
5753 }
5754 
5755 static int inet6_validate_link_af(const struct net_device *dev,
5756 				  const struct nlattr *nla)
5757 {
5758 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5759 	struct inet6_dev *idev = NULL;
5760 	int err;
5761 
5762 	if (dev) {
5763 		idev = __in6_dev_get(dev);
5764 		if (!idev)
5765 			return -EAFNOSUPPORT;
5766 	}
5767 
5768 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5769 					  inet6_af_policy, NULL);
5770 	if (err)
5771 		return err;
5772 
5773 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5774 		return -EINVAL;
5775 
5776 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5777 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5778 
5779 		if (check_addr_gen_mode(mode) < 0)
5780 			return -EINVAL;
5781 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5782 			return -EINVAL;
5783 	}
5784 
5785 	return 0;
5786 }
5787 
5788 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5789 {
5790 	struct inet6_dev *idev = __in6_dev_get(dev);
5791 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5792 	int err;
5793 
5794 	if (!idev)
5795 		return -EAFNOSUPPORT;
5796 
5797 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5798 		BUG();
5799 
5800 	if (tb[IFLA_INET6_TOKEN]) {
5801 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5802 		if (err)
5803 			return err;
5804 	}
5805 
5806 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5807 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5808 
5809 		idev->cnf.addr_gen_mode = mode;
5810 	}
5811 
5812 	return 0;
5813 }
5814 
5815 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5816 			     u32 portid, u32 seq, int event, unsigned int flags)
5817 {
5818 	struct net_device *dev = idev->dev;
5819 	struct ifinfomsg *hdr;
5820 	struct nlmsghdr *nlh;
5821 	void *protoinfo;
5822 
5823 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5824 	if (!nlh)
5825 		return -EMSGSIZE;
5826 
5827 	hdr = nlmsg_data(nlh);
5828 	hdr->ifi_family = AF_INET6;
5829 	hdr->__ifi_pad = 0;
5830 	hdr->ifi_type = dev->type;
5831 	hdr->ifi_index = dev->ifindex;
5832 	hdr->ifi_flags = dev_get_flags(dev);
5833 	hdr->ifi_change = 0;
5834 
5835 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5836 	    (dev->addr_len &&
5837 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5838 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5839 	    (dev->ifindex != dev_get_iflink(dev) &&
5840 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5841 	    nla_put_u8(skb, IFLA_OPERSTATE,
5842 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5843 		goto nla_put_failure;
5844 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5845 	if (!protoinfo)
5846 		goto nla_put_failure;
5847 
5848 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5849 		goto nla_put_failure;
5850 
5851 	nla_nest_end(skb, protoinfo);
5852 	nlmsg_end(skb, nlh);
5853 	return 0;
5854 
5855 nla_put_failure:
5856 	nlmsg_cancel(skb, nlh);
5857 	return -EMSGSIZE;
5858 }
5859 
5860 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5861 				   struct netlink_ext_ack *extack)
5862 {
5863 	struct ifinfomsg *ifm;
5864 
5865 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5866 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5867 		return -EINVAL;
5868 	}
5869 
5870 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5871 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5872 		return -EINVAL;
5873 	}
5874 
5875 	ifm = nlmsg_data(nlh);
5876 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5877 	    ifm->ifi_change || ifm->ifi_index) {
5878 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5879 		return -EINVAL;
5880 	}
5881 
5882 	return 0;
5883 }
5884 
5885 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5886 {
5887 	struct net *net = sock_net(skb->sk);
5888 	int h, s_h;
5889 	int idx = 0, s_idx;
5890 	struct net_device *dev;
5891 	struct inet6_dev *idev;
5892 	struct hlist_head *head;
5893 
5894 	/* only requests using strict checking can pass data to
5895 	 * influence the dump
5896 	 */
5897 	if (cb->strict_check) {
5898 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5899 
5900 		if (err < 0)
5901 			return err;
5902 	}
5903 
5904 	s_h = cb->args[0];
5905 	s_idx = cb->args[1];
5906 
5907 	rcu_read_lock();
5908 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5909 		idx = 0;
5910 		head = &net->dev_index_head[h];
5911 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5912 			if (idx < s_idx)
5913 				goto cont;
5914 			idev = __in6_dev_get(dev);
5915 			if (!idev)
5916 				goto cont;
5917 			if (inet6_fill_ifinfo(skb, idev,
5918 					      NETLINK_CB(cb->skb).portid,
5919 					      cb->nlh->nlmsg_seq,
5920 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5921 				goto out;
5922 cont:
5923 			idx++;
5924 		}
5925 	}
5926 out:
5927 	rcu_read_unlock();
5928 	cb->args[1] = idx;
5929 	cb->args[0] = h;
5930 
5931 	return skb->len;
5932 }
5933 
5934 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5935 {
5936 	struct sk_buff *skb;
5937 	struct net *net = dev_net(idev->dev);
5938 	int err = -ENOBUFS;
5939 
5940 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5941 	if (!skb)
5942 		goto errout;
5943 
5944 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5945 	if (err < 0) {
5946 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5947 		WARN_ON(err == -EMSGSIZE);
5948 		kfree_skb(skb);
5949 		goto errout;
5950 	}
5951 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5952 	return;
5953 errout:
5954 	if (err < 0)
5955 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5956 }
5957 
5958 static inline size_t inet6_prefix_nlmsg_size(void)
5959 {
5960 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5961 	       + nla_total_size(sizeof(struct in6_addr))
5962 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5963 }
5964 
5965 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5966 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5967 			     int event, unsigned int flags)
5968 {
5969 	struct prefixmsg *pmsg;
5970 	struct nlmsghdr *nlh;
5971 	struct prefix_cacheinfo	ci;
5972 
5973 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5974 	if (!nlh)
5975 		return -EMSGSIZE;
5976 
5977 	pmsg = nlmsg_data(nlh);
5978 	pmsg->prefix_family = AF_INET6;
5979 	pmsg->prefix_pad1 = 0;
5980 	pmsg->prefix_pad2 = 0;
5981 	pmsg->prefix_ifindex = idev->dev->ifindex;
5982 	pmsg->prefix_len = pinfo->prefix_len;
5983 	pmsg->prefix_type = pinfo->type;
5984 	pmsg->prefix_pad3 = 0;
5985 	pmsg->prefix_flags = 0;
5986 	if (pinfo->onlink)
5987 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5988 	if (pinfo->autoconf)
5989 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5990 
5991 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5992 		goto nla_put_failure;
5993 	ci.preferred_time = ntohl(pinfo->prefered);
5994 	ci.valid_time = ntohl(pinfo->valid);
5995 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5996 		goto nla_put_failure;
5997 	nlmsg_end(skb, nlh);
5998 	return 0;
5999 
6000 nla_put_failure:
6001 	nlmsg_cancel(skb, nlh);
6002 	return -EMSGSIZE;
6003 }
6004 
6005 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6006 			 struct prefix_info *pinfo)
6007 {
6008 	struct sk_buff *skb;
6009 	struct net *net = dev_net(idev->dev);
6010 	int err = -ENOBUFS;
6011 
6012 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6013 	if (!skb)
6014 		goto errout;
6015 
6016 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6017 	if (err < 0) {
6018 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6019 		WARN_ON(err == -EMSGSIZE);
6020 		kfree_skb(skb);
6021 		goto errout;
6022 	}
6023 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6024 	return;
6025 errout:
6026 	if (err < 0)
6027 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6028 }
6029 
6030 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6031 {
6032 	struct net *net = dev_net(ifp->idev->dev);
6033 
6034 	if (event)
6035 		ASSERT_RTNL();
6036 
6037 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6038 
6039 	switch (event) {
6040 	case RTM_NEWADDR:
6041 		/*
6042 		 * If the address was optimistic we inserted the route at the
6043 		 * start of our DAD process, so we don't need to do it again.
6044 		 * If the device was taken down in the middle of the DAD
6045 		 * cycle there is a race where we could get here without a
6046 		 * host route, so nothing to insert. That will be fixed when
6047 		 * the device is brought up.
6048 		 */
6049 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6050 			ip6_ins_rt(net, ifp->rt);
6051 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6052 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6053 				&ifp->addr, ifp->idev->dev->name);
6054 		}
6055 
6056 		if (ifp->idev->cnf.forwarding)
6057 			addrconf_join_anycast(ifp);
6058 		if (!ipv6_addr_any(&ifp->peer_addr))
6059 			addrconf_prefix_route(&ifp->peer_addr, 128,
6060 					      ifp->rt_priority, ifp->idev->dev,
6061 					      0, 0, GFP_ATOMIC);
6062 		break;
6063 	case RTM_DELADDR:
6064 		if (ifp->idev->cnf.forwarding)
6065 			addrconf_leave_anycast(ifp);
6066 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6067 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6068 			struct fib6_info *rt;
6069 
6070 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6071 						       ifp->idev->dev, 0, 0,
6072 						       false);
6073 			if (rt)
6074 				ip6_del_rt(net, rt, false);
6075 		}
6076 		if (ifp->rt) {
6077 			ip6_del_rt(net, ifp->rt, false);
6078 			ifp->rt = NULL;
6079 		}
6080 		rt_genid_bump_ipv6(net);
6081 		break;
6082 	}
6083 	atomic_inc(&net->ipv6.dev_addr_genid);
6084 }
6085 
6086 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6087 {
6088 	rcu_read_lock_bh();
6089 	if (likely(ifp->idev->dead == 0))
6090 		__ipv6_ifa_notify(event, ifp);
6091 	rcu_read_unlock_bh();
6092 }
6093 
6094 #ifdef CONFIG_SYSCTL
6095 
6096 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6097 		void *buffer, size_t *lenp, loff_t *ppos)
6098 {
6099 	int *valp = ctl->data;
6100 	int val = *valp;
6101 	loff_t pos = *ppos;
6102 	struct ctl_table lctl;
6103 	int ret;
6104 
6105 	/*
6106 	 * ctl->data points to idev->cnf.forwarding, we should
6107 	 * not modify it until we get the rtnl lock.
6108 	 */
6109 	lctl = *ctl;
6110 	lctl.data = &val;
6111 
6112 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6113 
6114 	if (write)
6115 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6116 	if (ret)
6117 		*ppos = pos;
6118 	return ret;
6119 }
6120 
6121 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6122 		void *buffer, size_t *lenp, loff_t *ppos)
6123 {
6124 	struct inet6_dev *idev = ctl->extra1;
6125 	int min_mtu = IPV6_MIN_MTU;
6126 	struct ctl_table lctl;
6127 
6128 	lctl = *ctl;
6129 	lctl.extra1 = &min_mtu;
6130 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6131 
6132 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6133 }
6134 
6135 static void dev_disable_change(struct inet6_dev *idev)
6136 {
6137 	struct netdev_notifier_info info;
6138 
6139 	if (!idev || !idev->dev)
6140 		return;
6141 
6142 	netdev_notifier_info_init(&info, idev->dev);
6143 	if (idev->cnf.disable_ipv6)
6144 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6145 	else
6146 		addrconf_notify(NULL, NETDEV_UP, &info);
6147 }
6148 
6149 static void addrconf_disable_change(struct net *net, __s32 newf)
6150 {
6151 	struct net_device *dev;
6152 	struct inet6_dev *idev;
6153 
6154 	for_each_netdev(net, dev) {
6155 		idev = __in6_dev_get(dev);
6156 		if (idev) {
6157 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6158 			idev->cnf.disable_ipv6 = newf;
6159 			if (changed)
6160 				dev_disable_change(idev);
6161 		}
6162 	}
6163 }
6164 
6165 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6166 {
6167 	struct net *net;
6168 	int old;
6169 
6170 	if (!rtnl_trylock())
6171 		return restart_syscall();
6172 
6173 	net = (struct net *)table->extra2;
6174 	old = *p;
6175 	*p = newf;
6176 
6177 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6178 		rtnl_unlock();
6179 		return 0;
6180 	}
6181 
6182 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6183 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6184 		addrconf_disable_change(net, newf);
6185 	} else if ((!newf) ^ (!old))
6186 		dev_disable_change((struct inet6_dev *)table->extra1);
6187 
6188 	rtnl_unlock();
6189 	return 0;
6190 }
6191 
6192 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6193 		void *buffer, size_t *lenp, loff_t *ppos)
6194 {
6195 	int *valp = ctl->data;
6196 	int val = *valp;
6197 	loff_t pos = *ppos;
6198 	struct ctl_table lctl;
6199 	int ret;
6200 
6201 	/*
6202 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6203 	 * not modify it until we get the rtnl lock.
6204 	 */
6205 	lctl = *ctl;
6206 	lctl.data = &val;
6207 
6208 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6209 
6210 	if (write)
6211 		ret = addrconf_disable_ipv6(ctl, valp, val);
6212 	if (ret)
6213 		*ppos = pos;
6214 	return ret;
6215 }
6216 
6217 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6218 		void *buffer, size_t *lenp, loff_t *ppos)
6219 {
6220 	int *valp = ctl->data;
6221 	int ret;
6222 	int old, new;
6223 
6224 	old = *valp;
6225 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6226 	new = *valp;
6227 
6228 	if (write && old != new) {
6229 		struct net *net = ctl->extra2;
6230 
6231 		if (!rtnl_trylock())
6232 			return restart_syscall();
6233 
6234 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6235 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6236 						     NETCONFA_PROXY_NEIGH,
6237 						     NETCONFA_IFINDEX_DEFAULT,
6238 						     net->ipv6.devconf_dflt);
6239 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6240 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6241 						     NETCONFA_PROXY_NEIGH,
6242 						     NETCONFA_IFINDEX_ALL,
6243 						     net->ipv6.devconf_all);
6244 		else {
6245 			struct inet6_dev *idev = ctl->extra1;
6246 
6247 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6248 						     NETCONFA_PROXY_NEIGH,
6249 						     idev->dev->ifindex,
6250 						     &idev->cnf);
6251 		}
6252 		rtnl_unlock();
6253 	}
6254 
6255 	return ret;
6256 }
6257 
6258 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6259 					 void *buffer, size_t *lenp,
6260 					 loff_t *ppos)
6261 {
6262 	int ret = 0;
6263 	u32 new_val;
6264 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6265 	struct net *net = (struct net *)ctl->extra2;
6266 	struct ctl_table tmp = {
6267 		.data = &new_val,
6268 		.maxlen = sizeof(new_val),
6269 		.mode = ctl->mode,
6270 	};
6271 
6272 	if (!rtnl_trylock())
6273 		return restart_syscall();
6274 
6275 	new_val = *((u32 *)ctl->data);
6276 
6277 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6278 	if (ret != 0)
6279 		goto out;
6280 
6281 	if (write) {
6282 		if (check_addr_gen_mode(new_val) < 0) {
6283 			ret = -EINVAL;
6284 			goto out;
6285 		}
6286 
6287 		if (idev) {
6288 			if (check_stable_privacy(idev, net, new_val) < 0) {
6289 				ret = -EINVAL;
6290 				goto out;
6291 			}
6292 
6293 			if (idev->cnf.addr_gen_mode != new_val) {
6294 				idev->cnf.addr_gen_mode = new_val;
6295 				addrconf_dev_config(idev->dev);
6296 			}
6297 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6298 			struct net_device *dev;
6299 
6300 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6301 			for_each_netdev(net, dev) {
6302 				idev = __in6_dev_get(dev);
6303 				if (idev &&
6304 				    idev->cnf.addr_gen_mode != new_val) {
6305 					idev->cnf.addr_gen_mode = new_val;
6306 					addrconf_dev_config(idev->dev);
6307 				}
6308 			}
6309 		}
6310 
6311 		*((u32 *)ctl->data) = new_val;
6312 	}
6313 
6314 out:
6315 	rtnl_unlock();
6316 
6317 	return ret;
6318 }
6319 
6320 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6321 					 void *buffer, size_t *lenp,
6322 					 loff_t *ppos)
6323 {
6324 	int err;
6325 	struct in6_addr addr;
6326 	char str[IPV6_MAX_STRLEN];
6327 	struct ctl_table lctl = *ctl;
6328 	struct net *net = ctl->extra2;
6329 	struct ipv6_stable_secret *secret = ctl->data;
6330 
6331 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6332 		return -EIO;
6333 
6334 	lctl.maxlen = IPV6_MAX_STRLEN;
6335 	lctl.data = str;
6336 
6337 	if (!rtnl_trylock())
6338 		return restart_syscall();
6339 
6340 	if (!write && !secret->initialized) {
6341 		err = -EIO;
6342 		goto out;
6343 	}
6344 
6345 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6346 	if (err >= sizeof(str)) {
6347 		err = -EIO;
6348 		goto out;
6349 	}
6350 
6351 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6352 	if (err || !write)
6353 		goto out;
6354 
6355 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6356 		err = -EIO;
6357 		goto out;
6358 	}
6359 
6360 	secret->initialized = true;
6361 	secret->secret = addr;
6362 
6363 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6364 		struct net_device *dev;
6365 
6366 		for_each_netdev(net, dev) {
6367 			struct inet6_dev *idev = __in6_dev_get(dev);
6368 
6369 			if (idev) {
6370 				idev->cnf.addr_gen_mode =
6371 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6372 			}
6373 		}
6374 	} else {
6375 		struct inet6_dev *idev = ctl->extra1;
6376 
6377 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6378 	}
6379 
6380 out:
6381 	rtnl_unlock();
6382 
6383 	return err;
6384 }
6385 
6386 static
6387 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6388 						int write, void *buffer,
6389 						size_t *lenp,
6390 						loff_t *ppos)
6391 {
6392 	int *valp = ctl->data;
6393 	int val = *valp;
6394 	loff_t pos = *ppos;
6395 	struct ctl_table lctl;
6396 	int ret;
6397 
6398 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6399 	 * we should not modify it until we get the rtnl lock.
6400 	 */
6401 	lctl = *ctl;
6402 	lctl.data = &val;
6403 
6404 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6405 
6406 	if (write)
6407 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6408 	if (ret)
6409 		*ppos = pos;
6410 	return ret;
6411 }
6412 
6413 static
6414 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6415 {
6416 	if (rt) {
6417 		if (action)
6418 			rt->dst.flags |= DST_NOPOLICY;
6419 		else
6420 			rt->dst.flags &= ~DST_NOPOLICY;
6421 	}
6422 }
6423 
6424 static
6425 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6426 {
6427 	struct inet6_ifaddr *ifa;
6428 
6429 	read_lock_bh(&idev->lock);
6430 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6431 		spin_lock(&ifa->lock);
6432 		if (ifa->rt) {
6433 			/* host routes only use builtin fib6_nh */
6434 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6435 			int cpu;
6436 
6437 			rcu_read_lock();
6438 			ifa->rt->dst_nopolicy = val ? true : false;
6439 			if (nh->rt6i_pcpu) {
6440 				for_each_possible_cpu(cpu) {
6441 					struct rt6_info **rtp;
6442 
6443 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6444 					addrconf_set_nopolicy(*rtp, val);
6445 				}
6446 			}
6447 			rcu_read_unlock();
6448 		}
6449 		spin_unlock(&ifa->lock);
6450 	}
6451 	read_unlock_bh(&idev->lock);
6452 }
6453 
6454 static
6455 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6456 {
6457 	struct inet6_dev *idev;
6458 	struct net *net;
6459 
6460 	if (!rtnl_trylock())
6461 		return restart_syscall();
6462 
6463 	*valp = val;
6464 
6465 	net = (struct net *)ctl->extra2;
6466 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6467 		rtnl_unlock();
6468 		return 0;
6469 	}
6470 
6471 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6472 		struct net_device *dev;
6473 
6474 		for_each_netdev(net, dev) {
6475 			idev = __in6_dev_get(dev);
6476 			if (idev)
6477 				addrconf_disable_policy_idev(idev, val);
6478 		}
6479 	} else {
6480 		idev = (struct inet6_dev *)ctl->extra1;
6481 		addrconf_disable_policy_idev(idev, val);
6482 	}
6483 
6484 	rtnl_unlock();
6485 	return 0;
6486 }
6487 
6488 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6489 				   void *buffer, size_t *lenp, loff_t *ppos)
6490 {
6491 	int *valp = ctl->data;
6492 	int val = *valp;
6493 	loff_t pos = *ppos;
6494 	struct ctl_table lctl;
6495 	int ret;
6496 
6497 	lctl = *ctl;
6498 	lctl.data = &val;
6499 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6500 
6501 	if (write && (*valp != val))
6502 		ret = addrconf_disable_policy(ctl, valp, val);
6503 
6504 	if (ret)
6505 		*ppos = pos;
6506 
6507 	return ret;
6508 }
6509 
6510 static int minus_one = -1;
6511 static const int two_five_five = 255;
6512 
6513 static const struct ctl_table addrconf_sysctl[] = {
6514 	{
6515 		.procname	= "forwarding",
6516 		.data		= &ipv6_devconf.forwarding,
6517 		.maxlen		= sizeof(int),
6518 		.mode		= 0644,
6519 		.proc_handler	= addrconf_sysctl_forward,
6520 	},
6521 	{
6522 		.procname	= "hop_limit",
6523 		.data		= &ipv6_devconf.hop_limit,
6524 		.maxlen		= sizeof(int),
6525 		.mode		= 0644,
6526 		.proc_handler	= proc_dointvec_minmax,
6527 		.extra1		= (void *)SYSCTL_ONE,
6528 		.extra2		= (void *)&two_five_five,
6529 	},
6530 	{
6531 		.procname	= "mtu",
6532 		.data		= &ipv6_devconf.mtu6,
6533 		.maxlen		= sizeof(int),
6534 		.mode		= 0644,
6535 		.proc_handler	= addrconf_sysctl_mtu,
6536 	},
6537 	{
6538 		.procname	= "accept_ra",
6539 		.data		= &ipv6_devconf.accept_ra,
6540 		.maxlen		= sizeof(int),
6541 		.mode		= 0644,
6542 		.proc_handler	= proc_dointvec,
6543 	},
6544 	{
6545 		.procname	= "accept_redirects",
6546 		.data		= &ipv6_devconf.accept_redirects,
6547 		.maxlen		= sizeof(int),
6548 		.mode		= 0644,
6549 		.proc_handler	= proc_dointvec,
6550 	},
6551 	{
6552 		.procname	= "autoconf",
6553 		.data		= &ipv6_devconf.autoconf,
6554 		.maxlen		= sizeof(int),
6555 		.mode		= 0644,
6556 		.proc_handler	= proc_dointvec,
6557 	},
6558 	{
6559 		.procname	= "dad_transmits",
6560 		.data		= &ipv6_devconf.dad_transmits,
6561 		.maxlen		= sizeof(int),
6562 		.mode		= 0644,
6563 		.proc_handler	= proc_dointvec,
6564 	},
6565 	{
6566 		.procname	= "router_solicitations",
6567 		.data		= &ipv6_devconf.rtr_solicits,
6568 		.maxlen		= sizeof(int),
6569 		.mode		= 0644,
6570 		.proc_handler	= proc_dointvec_minmax,
6571 		.extra1		= &minus_one,
6572 	},
6573 	{
6574 		.procname	= "router_solicitation_interval",
6575 		.data		= &ipv6_devconf.rtr_solicit_interval,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec_jiffies,
6579 	},
6580 	{
6581 		.procname	= "router_solicitation_max_interval",
6582 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6583 		.maxlen		= sizeof(int),
6584 		.mode		= 0644,
6585 		.proc_handler	= proc_dointvec_jiffies,
6586 	},
6587 	{
6588 		.procname	= "router_solicitation_delay",
6589 		.data		= &ipv6_devconf.rtr_solicit_delay,
6590 		.maxlen		= sizeof(int),
6591 		.mode		= 0644,
6592 		.proc_handler	= proc_dointvec_jiffies,
6593 	},
6594 	{
6595 		.procname	= "force_mld_version",
6596 		.data		= &ipv6_devconf.force_mld_version,
6597 		.maxlen		= sizeof(int),
6598 		.mode		= 0644,
6599 		.proc_handler	= proc_dointvec,
6600 	},
6601 	{
6602 		.procname	= "mldv1_unsolicited_report_interval",
6603 		.data		=
6604 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6605 		.maxlen		= sizeof(int),
6606 		.mode		= 0644,
6607 		.proc_handler	= proc_dointvec_ms_jiffies,
6608 	},
6609 	{
6610 		.procname	= "mldv2_unsolicited_report_interval",
6611 		.data		=
6612 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6613 		.maxlen		= sizeof(int),
6614 		.mode		= 0644,
6615 		.proc_handler	= proc_dointvec_ms_jiffies,
6616 	},
6617 	{
6618 		.procname	= "use_tempaddr",
6619 		.data		= &ipv6_devconf.use_tempaddr,
6620 		.maxlen		= sizeof(int),
6621 		.mode		= 0644,
6622 		.proc_handler	= proc_dointvec,
6623 	},
6624 	{
6625 		.procname	= "temp_valid_lft",
6626 		.data		= &ipv6_devconf.temp_valid_lft,
6627 		.maxlen		= sizeof(int),
6628 		.mode		= 0644,
6629 		.proc_handler	= proc_dointvec,
6630 	},
6631 	{
6632 		.procname	= "temp_prefered_lft",
6633 		.data		= &ipv6_devconf.temp_prefered_lft,
6634 		.maxlen		= sizeof(int),
6635 		.mode		= 0644,
6636 		.proc_handler	= proc_dointvec,
6637 	},
6638 	{
6639 		.procname	= "regen_max_retry",
6640 		.data		= &ipv6_devconf.regen_max_retry,
6641 		.maxlen		= sizeof(int),
6642 		.mode		= 0644,
6643 		.proc_handler	= proc_dointvec,
6644 	},
6645 	{
6646 		.procname	= "max_desync_factor",
6647 		.data		= &ipv6_devconf.max_desync_factor,
6648 		.maxlen		= sizeof(int),
6649 		.mode		= 0644,
6650 		.proc_handler	= proc_dointvec,
6651 	},
6652 	{
6653 		.procname	= "max_addresses",
6654 		.data		= &ipv6_devconf.max_addresses,
6655 		.maxlen		= sizeof(int),
6656 		.mode		= 0644,
6657 		.proc_handler	= proc_dointvec,
6658 	},
6659 	{
6660 		.procname	= "accept_ra_defrtr",
6661 		.data		= &ipv6_devconf.accept_ra_defrtr,
6662 		.maxlen		= sizeof(int),
6663 		.mode		= 0644,
6664 		.proc_handler	= proc_dointvec,
6665 	},
6666 	{
6667 		.procname	= "accept_ra_min_hop_limit",
6668 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6669 		.maxlen		= sizeof(int),
6670 		.mode		= 0644,
6671 		.proc_handler	= proc_dointvec,
6672 	},
6673 	{
6674 		.procname	= "accept_ra_pinfo",
6675 		.data		= &ipv6_devconf.accept_ra_pinfo,
6676 		.maxlen		= sizeof(int),
6677 		.mode		= 0644,
6678 		.proc_handler	= proc_dointvec,
6679 	},
6680 #ifdef CONFIG_IPV6_ROUTER_PREF
6681 	{
6682 		.procname	= "accept_ra_rtr_pref",
6683 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6684 		.maxlen		= sizeof(int),
6685 		.mode		= 0644,
6686 		.proc_handler	= proc_dointvec,
6687 	},
6688 	{
6689 		.procname	= "router_probe_interval",
6690 		.data		= &ipv6_devconf.rtr_probe_interval,
6691 		.maxlen		= sizeof(int),
6692 		.mode		= 0644,
6693 		.proc_handler	= proc_dointvec_jiffies,
6694 	},
6695 #ifdef CONFIG_IPV6_ROUTE_INFO
6696 	{
6697 		.procname	= "accept_ra_rt_info_min_plen",
6698 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6699 		.maxlen		= sizeof(int),
6700 		.mode		= 0644,
6701 		.proc_handler	= proc_dointvec,
6702 	},
6703 	{
6704 		.procname	= "accept_ra_rt_info_max_plen",
6705 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6706 		.maxlen		= sizeof(int),
6707 		.mode		= 0644,
6708 		.proc_handler	= proc_dointvec,
6709 	},
6710 #endif
6711 #endif
6712 	{
6713 		.procname	= "proxy_ndp",
6714 		.data		= &ipv6_devconf.proxy_ndp,
6715 		.maxlen		= sizeof(int),
6716 		.mode		= 0644,
6717 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6718 	},
6719 	{
6720 		.procname	= "accept_source_route",
6721 		.data		= &ipv6_devconf.accept_source_route,
6722 		.maxlen		= sizeof(int),
6723 		.mode		= 0644,
6724 		.proc_handler	= proc_dointvec,
6725 	},
6726 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6727 	{
6728 		.procname	= "optimistic_dad",
6729 		.data		= &ipv6_devconf.optimistic_dad,
6730 		.maxlen		= sizeof(int),
6731 		.mode		= 0644,
6732 		.proc_handler   = proc_dointvec,
6733 	},
6734 	{
6735 		.procname	= "use_optimistic",
6736 		.data		= &ipv6_devconf.use_optimistic,
6737 		.maxlen		= sizeof(int),
6738 		.mode		= 0644,
6739 		.proc_handler	= proc_dointvec,
6740 	},
6741 #endif
6742 #ifdef CONFIG_IPV6_MROUTE
6743 	{
6744 		.procname	= "mc_forwarding",
6745 		.data		= &ipv6_devconf.mc_forwarding,
6746 		.maxlen		= sizeof(int),
6747 		.mode		= 0444,
6748 		.proc_handler	= proc_dointvec,
6749 	},
6750 #endif
6751 	{
6752 		.procname	= "disable_ipv6",
6753 		.data		= &ipv6_devconf.disable_ipv6,
6754 		.maxlen		= sizeof(int),
6755 		.mode		= 0644,
6756 		.proc_handler	= addrconf_sysctl_disable,
6757 	},
6758 	{
6759 		.procname	= "accept_dad",
6760 		.data		= &ipv6_devconf.accept_dad,
6761 		.maxlen		= sizeof(int),
6762 		.mode		= 0644,
6763 		.proc_handler	= proc_dointvec,
6764 	},
6765 	{
6766 		.procname	= "force_tllao",
6767 		.data		= &ipv6_devconf.force_tllao,
6768 		.maxlen		= sizeof(int),
6769 		.mode		= 0644,
6770 		.proc_handler	= proc_dointvec
6771 	},
6772 	{
6773 		.procname	= "ndisc_notify",
6774 		.data		= &ipv6_devconf.ndisc_notify,
6775 		.maxlen		= sizeof(int),
6776 		.mode		= 0644,
6777 		.proc_handler	= proc_dointvec
6778 	},
6779 	{
6780 		.procname	= "suppress_frag_ndisc",
6781 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6782 		.maxlen		= sizeof(int),
6783 		.mode		= 0644,
6784 		.proc_handler	= proc_dointvec
6785 	},
6786 	{
6787 		.procname	= "accept_ra_from_local",
6788 		.data		= &ipv6_devconf.accept_ra_from_local,
6789 		.maxlen		= sizeof(int),
6790 		.mode		= 0644,
6791 		.proc_handler	= proc_dointvec,
6792 	},
6793 	{
6794 		.procname	= "accept_ra_mtu",
6795 		.data		= &ipv6_devconf.accept_ra_mtu,
6796 		.maxlen		= sizeof(int),
6797 		.mode		= 0644,
6798 		.proc_handler	= proc_dointvec,
6799 	},
6800 	{
6801 		.procname	= "stable_secret",
6802 		.data		= &ipv6_devconf.stable_secret,
6803 		.maxlen		= IPV6_MAX_STRLEN,
6804 		.mode		= 0600,
6805 		.proc_handler	= addrconf_sysctl_stable_secret,
6806 	},
6807 	{
6808 		.procname	= "use_oif_addrs_only",
6809 		.data		= &ipv6_devconf.use_oif_addrs_only,
6810 		.maxlen		= sizeof(int),
6811 		.mode		= 0644,
6812 		.proc_handler	= proc_dointvec,
6813 	},
6814 	{
6815 		.procname	= "ignore_routes_with_linkdown",
6816 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6817 		.maxlen		= sizeof(int),
6818 		.mode		= 0644,
6819 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6820 	},
6821 	{
6822 		.procname	= "drop_unicast_in_l2_multicast",
6823 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6824 		.maxlen		= sizeof(int),
6825 		.mode		= 0644,
6826 		.proc_handler	= proc_dointvec,
6827 	},
6828 	{
6829 		.procname	= "drop_unsolicited_na",
6830 		.data		= &ipv6_devconf.drop_unsolicited_na,
6831 		.maxlen		= sizeof(int),
6832 		.mode		= 0644,
6833 		.proc_handler	= proc_dointvec,
6834 	},
6835 	{
6836 		.procname	= "keep_addr_on_down",
6837 		.data		= &ipv6_devconf.keep_addr_on_down,
6838 		.maxlen		= sizeof(int),
6839 		.mode		= 0644,
6840 		.proc_handler	= proc_dointvec,
6841 
6842 	},
6843 	{
6844 		.procname	= "seg6_enabled",
6845 		.data		= &ipv6_devconf.seg6_enabled,
6846 		.maxlen		= sizeof(int),
6847 		.mode		= 0644,
6848 		.proc_handler	= proc_dointvec,
6849 	},
6850 #ifdef CONFIG_IPV6_SEG6_HMAC
6851 	{
6852 		.procname	= "seg6_require_hmac",
6853 		.data		= &ipv6_devconf.seg6_require_hmac,
6854 		.maxlen		= sizeof(int),
6855 		.mode		= 0644,
6856 		.proc_handler	= proc_dointvec,
6857 	},
6858 #endif
6859 	{
6860 		.procname       = "enhanced_dad",
6861 		.data           = &ipv6_devconf.enhanced_dad,
6862 		.maxlen         = sizeof(int),
6863 		.mode           = 0644,
6864 		.proc_handler   = proc_dointvec,
6865 	},
6866 	{
6867 		.procname		= "addr_gen_mode",
6868 		.data			= &ipv6_devconf.addr_gen_mode,
6869 		.maxlen			= sizeof(int),
6870 		.mode			= 0644,
6871 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6872 	},
6873 	{
6874 		.procname       = "disable_policy",
6875 		.data           = &ipv6_devconf.disable_policy,
6876 		.maxlen         = sizeof(int),
6877 		.mode           = 0644,
6878 		.proc_handler   = addrconf_sysctl_disable_policy,
6879 	},
6880 	{
6881 		.procname	= "ndisc_tclass",
6882 		.data		= &ipv6_devconf.ndisc_tclass,
6883 		.maxlen		= sizeof(int),
6884 		.mode		= 0644,
6885 		.proc_handler	= proc_dointvec_minmax,
6886 		.extra1		= (void *)SYSCTL_ZERO,
6887 		.extra2		= (void *)&two_five_five,
6888 	},
6889 	{
6890 		.procname	= "rpl_seg_enabled",
6891 		.data		= &ipv6_devconf.rpl_seg_enabled,
6892 		.maxlen		= sizeof(int),
6893 		.mode		= 0644,
6894 		.proc_handler	= proc_dointvec,
6895 	},
6896 	{
6897 		/* sentinel */
6898 	}
6899 };
6900 
6901 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6902 		struct inet6_dev *idev, struct ipv6_devconf *p)
6903 {
6904 	int i, ifindex;
6905 	struct ctl_table *table;
6906 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6907 
6908 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6909 	if (!table)
6910 		goto out;
6911 
6912 	for (i = 0; table[i].data; i++) {
6913 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6914 		/* If one of these is already set, then it is not safe to
6915 		 * overwrite either of them: this makes proc_dointvec_minmax
6916 		 * usable.
6917 		 */
6918 		if (!table[i].extra1 && !table[i].extra2) {
6919 			table[i].extra1 = idev; /* embedded; no ref */
6920 			table[i].extra2 = net;
6921 		}
6922 	}
6923 
6924 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6925 
6926 	p->sysctl_header = register_net_sysctl(net, path, table);
6927 	if (!p->sysctl_header)
6928 		goto free;
6929 
6930 	if (!strcmp(dev_name, "all"))
6931 		ifindex = NETCONFA_IFINDEX_ALL;
6932 	else if (!strcmp(dev_name, "default"))
6933 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6934 	else
6935 		ifindex = idev->dev->ifindex;
6936 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6937 				     ifindex, p);
6938 	return 0;
6939 
6940 free:
6941 	kfree(table);
6942 out:
6943 	return -ENOBUFS;
6944 }
6945 
6946 static void __addrconf_sysctl_unregister(struct net *net,
6947 					 struct ipv6_devconf *p, int ifindex)
6948 {
6949 	struct ctl_table *table;
6950 
6951 	if (!p->sysctl_header)
6952 		return;
6953 
6954 	table = p->sysctl_header->ctl_table_arg;
6955 	unregister_net_sysctl_table(p->sysctl_header);
6956 	p->sysctl_header = NULL;
6957 	kfree(table);
6958 
6959 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6960 }
6961 
6962 static int addrconf_sysctl_register(struct inet6_dev *idev)
6963 {
6964 	int err;
6965 
6966 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6967 		return -EINVAL;
6968 
6969 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6970 				    &ndisc_ifinfo_sysctl_change);
6971 	if (err)
6972 		return err;
6973 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6974 					 idev, &idev->cnf);
6975 	if (err)
6976 		neigh_sysctl_unregister(idev->nd_parms);
6977 
6978 	return err;
6979 }
6980 
6981 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6982 {
6983 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6984 				     idev->dev->ifindex);
6985 	neigh_sysctl_unregister(idev->nd_parms);
6986 }
6987 
6988 
6989 #endif
6990 
6991 static int __net_init addrconf_init_net(struct net *net)
6992 {
6993 	int err = -ENOMEM;
6994 	struct ipv6_devconf *all, *dflt;
6995 
6996 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6997 	if (!all)
6998 		goto err_alloc_all;
6999 
7000 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7001 	if (!dflt)
7002 		goto err_alloc_dflt;
7003 
7004 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7005 	    !net_eq(net, &init_net)) {
7006 		switch (sysctl_devconf_inherit_init_net) {
7007 		case 1:  /* copy from init_net */
7008 			memcpy(all, init_net.ipv6.devconf_all,
7009 			       sizeof(ipv6_devconf));
7010 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7011 			       sizeof(ipv6_devconf_dflt));
7012 			break;
7013 		case 3: /* copy from the current netns */
7014 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7015 			       sizeof(ipv6_devconf));
7016 			memcpy(dflt,
7017 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7018 			       sizeof(ipv6_devconf_dflt));
7019 			break;
7020 		case 0:
7021 		case 2:
7022 			/* use compiled values */
7023 			break;
7024 		}
7025 	}
7026 
7027 	/* these will be inherited by all namespaces */
7028 	dflt->autoconf = ipv6_defaults.autoconf;
7029 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7030 
7031 	dflt->stable_secret.initialized = false;
7032 	all->stable_secret.initialized = false;
7033 
7034 	net->ipv6.devconf_all = all;
7035 	net->ipv6.devconf_dflt = dflt;
7036 
7037 #ifdef CONFIG_SYSCTL
7038 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7039 	if (err < 0)
7040 		goto err_reg_all;
7041 
7042 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7043 	if (err < 0)
7044 		goto err_reg_dflt;
7045 #endif
7046 	return 0;
7047 
7048 #ifdef CONFIG_SYSCTL
7049 err_reg_dflt:
7050 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7051 err_reg_all:
7052 	kfree(dflt);
7053 #endif
7054 err_alloc_dflt:
7055 	kfree(all);
7056 err_alloc_all:
7057 	return err;
7058 }
7059 
7060 static void __net_exit addrconf_exit_net(struct net *net)
7061 {
7062 #ifdef CONFIG_SYSCTL
7063 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7064 				     NETCONFA_IFINDEX_DEFAULT);
7065 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7066 				     NETCONFA_IFINDEX_ALL);
7067 #endif
7068 	kfree(net->ipv6.devconf_dflt);
7069 	kfree(net->ipv6.devconf_all);
7070 }
7071 
7072 static struct pernet_operations addrconf_ops = {
7073 	.init = addrconf_init_net,
7074 	.exit = addrconf_exit_net,
7075 };
7076 
7077 static struct rtnl_af_ops inet6_ops __read_mostly = {
7078 	.family		  = AF_INET6,
7079 	.fill_link_af	  = inet6_fill_link_af,
7080 	.get_link_af_size = inet6_get_link_af_size,
7081 	.validate_link_af = inet6_validate_link_af,
7082 	.set_link_af	  = inet6_set_link_af,
7083 };
7084 
7085 /*
7086  *	Init / cleanup code
7087  */
7088 
7089 int __init addrconf_init(void)
7090 {
7091 	struct inet6_dev *idev;
7092 	int i, err;
7093 
7094 	err = ipv6_addr_label_init();
7095 	if (err < 0) {
7096 		pr_crit("%s: cannot initialize default policy table: %d\n",
7097 			__func__, err);
7098 		goto out;
7099 	}
7100 
7101 	err = register_pernet_subsys(&addrconf_ops);
7102 	if (err < 0)
7103 		goto out_addrlabel;
7104 
7105 	addrconf_wq = create_workqueue("ipv6_addrconf");
7106 	if (!addrconf_wq) {
7107 		err = -ENOMEM;
7108 		goto out_nowq;
7109 	}
7110 
7111 	/* The addrconf netdev notifier requires that loopback_dev
7112 	 * has it's ipv6 private information allocated and setup
7113 	 * before it can bring up and give link-local addresses
7114 	 * to other devices which are up.
7115 	 *
7116 	 * Unfortunately, loopback_dev is not necessarily the first
7117 	 * entry in the global dev_base list of net devices.  In fact,
7118 	 * it is likely to be the very last entry on that list.
7119 	 * So this causes the notifier registry below to try and
7120 	 * give link-local addresses to all devices besides loopback_dev
7121 	 * first, then loopback_dev, which cases all the non-loopback_dev
7122 	 * devices to fail to get a link-local address.
7123 	 *
7124 	 * So, as a temporary fix, allocate the ipv6 structure for
7125 	 * loopback_dev first by hand.
7126 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7127 	 * device and it being up should be removed.
7128 	 */
7129 	rtnl_lock();
7130 	idev = ipv6_add_dev(init_net.loopback_dev);
7131 	rtnl_unlock();
7132 	if (IS_ERR(idev)) {
7133 		err = PTR_ERR(idev);
7134 		goto errlo;
7135 	}
7136 
7137 	ip6_route_init_special_entries();
7138 
7139 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7140 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7141 
7142 	register_netdevice_notifier(&ipv6_dev_notf);
7143 
7144 	addrconf_verify();
7145 
7146 	rtnl_af_register(&inet6_ops);
7147 
7148 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7149 				   NULL, inet6_dump_ifinfo, 0);
7150 	if (err < 0)
7151 		goto errout;
7152 
7153 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7154 				   inet6_rtm_newaddr, NULL, 0);
7155 	if (err < 0)
7156 		goto errout;
7157 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7158 				   inet6_rtm_deladdr, NULL, 0);
7159 	if (err < 0)
7160 		goto errout;
7161 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7162 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7163 				   RTNL_FLAG_DOIT_UNLOCKED);
7164 	if (err < 0)
7165 		goto errout;
7166 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7167 				   NULL, inet6_dump_ifmcaddr, 0);
7168 	if (err < 0)
7169 		goto errout;
7170 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7171 				   NULL, inet6_dump_ifacaddr, 0);
7172 	if (err < 0)
7173 		goto errout;
7174 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7175 				   inet6_netconf_get_devconf,
7176 				   inet6_netconf_dump_devconf,
7177 				   RTNL_FLAG_DOIT_UNLOCKED);
7178 	if (err < 0)
7179 		goto errout;
7180 	err = ipv6_addr_label_rtnl_register();
7181 	if (err < 0)
7182 		goto errout;
7183 
7184 	return 0;
7185 errout:
7186 	rtnl_unregister_all(PF_INET6);
7187 	rtnl_af_unregister(&inet6_ops);
7188 	unregister_netdevice_notifier(&ipv6_dev_notf);
7189 errlo:
7190 	destroy_workqueue(addrconf_wq);
7191 out_nowq:
7192 	unregister_pernet_subsys(&addrconf_ops);
7193 out_addrlabel:
7194 	ipv6_addr_label_cleanup();
7195 out:
7196 	return err;
7197 }
7198 
7199 void addrconf_cleanup(void)
7200 {
7201 	struct net_device *dev;
7202 	int i;
7203 
7204 	unregister_netdevice_notifier(&ipv6_dev_notf);
7205 	unregister_pernet_subsys(&addrconf_ops);
7206 	ipv6_addr_label_cleanup();
7207 
7208 	rtnl_af_unregister(&inet6_ops);
7209 
7210 	rtnl_lock();
7211 
7212 	/* clean dev list */
7213 	for_each_netdev(&init_net, dev) {
7214 		if (__in6_dev_get(dev) == NULL)
7215 			continue;
7216 		addrconf_ifdown(dev, true);
7217 	}
7218 	addrconf_ifdown(init_net.loopback_dev, true);
7219 
7220 	/*
7221 	 *	Check hash table.
7222 	 */
7223 	spin_lock_bh(&addrconf_hash_lock);
7224 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7225 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7226 	spin_unlock_bh(&addrconf_hash_lock);
7227 	cancel_delayed_work(&addr_chk_work);
7228 	rtnl_unlock();
7229 
7230 	destroy_workqueue(addrconf_wq);
7231 }
7232