xref: /linux/net/ipv6/addrconf.c (revision 40e79150c1686263e6a031d7702aec63aff31332)
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_regen_rndid(struct inet6_dev *idev);
139 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 /*
150  *	Configured unicast address hash table
151  */
152 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
153 static DEFINE_SPINLOCK(addrconf_hash_lock);
154 
155 static void addrconf_verify(void);
156 static void addrconf_verify_rtnl(void);
157 static void addrconf_verify_work(struct work_struct *);
158 
159 static struct workqueue_struct *addrconf_wq;
160 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
161 
162 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
163 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
164 
165 static void addrconf_type_change(struct net_device *dev,
166 				 unsigned long event);
167 static int addrconf_ifdown(struct net_device *dev, int how);
168 
169 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
170 						  int plen,
171 						  const struct net_device *dev,
172 						  u32 flags, u32 noflags,
173 						  bool no_gw);
174 
175 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
176 static void addrconf_dad_work(struct work_struct *w);
177 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
178 				   bool send_na);
179 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
180 static void addrconf_rs_timer(struct timer_list *t);
181 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
183 
184 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
185 				struct prefix_info *pinfo);
186 
187 static struct ipv6_devconf ipv6_devconf __read_mostly = {
188 	.forwarding		= 0,
189 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
190 	.mtu6			= IPV6_MIN_MTU,
191 	.accept_ra		= 1,
192 	.accept_redirects	= 1,
193 	.autoconf		= 1,
194 	.force_mld_version	= 0,
195 	.mldv1_unsolicited_report_interval = 10 * HZ,
196 	.mldv2_unsolicited_report_interval = HZ,
197 	.dad_transmits		= 1,
198 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
199 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
200 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
201 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
202 	.use_tempaddr		= 0,
203 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
204 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
205 	.regen_max_retry	= REGEN_MAX_RETRY,
206 	.max_desync_factor	= MAX_DESYNC_FACTOR,
207 	.max_addresses		= IPV6_MAX_ADDRESSES,
208 	.accept_ra_defrtr	= 1,
209 	.accept_ra_from_local	= 0,
210 	.accept_ra_min_hop_limit= 1,
211 	.accept_ra_pinfo	= 1,
212 #ifdef CONFIG_IPV6_ROUTER_PREF
213 	.accept_ra_rtr_pref	= 1,
214 	.rtr_probe_interval	= 60 * HZ,
215 #ifdef CONFIG_IPV6_ROUTE_INFO
216 	.accept_ra_rt_info_min_plen = 0,
217 	.accept_ra_rt_info_max_plen = 0,
218 #endif
219 #endif
220 	.proxy_ndp		= 0,
221 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
222 	.disable_ipv6		= 0,
223 	.accept_dad		= 0,
224 	.suppress_frag_ndisc	= 1,
225 	.accept_ra_mtu		= 1,
226 	.stable_secret		= {
227 		.initialized = false,
228 	},
229 	.use_oif_addrs_only	= 0,
230 	.ignore_routes_with_linkdown = 0,
231 	.keep_addr_on_down	= 0,
232 	.seg6_enabled		= 0,
233 #ifdef CONFIG_IPV6_SEG6_HMAC
234 	.seg6_require_hmac	= 0,
235 #endif
236 	.enhanced_dad           = 1,
237 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
238 	.disable_policy		= 0,
239 	.rpl_seg_enabled	= 0,
240 };
241 
242 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
243 	.forwarding		= 0,
244 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
245 	.mtu6			= IPV6_MIN_MTU,
246 	.accept_ra		= 1,
247 	.accept_redirects	= 1,
248 	.autoconf		= 1,
249 	.force_mld_version	= 0,
250 	.mldv1_unsolicited_report_interval = 10 * HZ,
251 	.mldv2_unsolicited_report_interval = HZ,
252 	.dad_transmits		= 1,
253 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
254 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
255 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
256 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
257 	.use_tempaddr		= 0,
258 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
259 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
260 	.regen_max_retry	= REGEN_MAX_RETRY,
261 	.max_desync_factor	= MAX_DESYNC_FACTOR,
262 	.max_addresses		= IPV6_MAX_ADDRESSES,
263 	.accept_ra_defrtr	= 1,
264 	.accept_ra_from_local	= 0,
265 	.accept_ra_min_hop_limit= 1,
266 	.accept_ra_pinfo	= 1,
267 #ifdef CONFIG_IPV6_ROUTER_PREF
268 	.accept_ra_rtr_pref	= 1,
269 	.rtr_probe_interval	= 60 * HZ,
270 #ifdef CONFIG_IPV6_ROUTE_INFO
271 	.accept_ra_rt_info_min_plen = 0,
272 	.accept_ra_rt_info_max_plen = 0,
273 #endif
274 #endif
275 	.proxy_ndp		= 0,
276 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
277 	.disable_ipv6		= 0,
278 	.accept_dad		= 1,
279 	.suppress_frag_ndisc	= 1,
280 	.accept_ra_mtu		= 1,
281 	.stable_secret		= {
282 		.initialized = false,
283 	},
284 	.use_oif_addrs_only	= 0,
285 	.ignore_routes_with_linkdown = 0,
286 	.keep_addr_on_down	= 0,
287 	.seg6_enabled		= 0,
288 #ifdef CONFIG_IPV6_SEG6_HMAC
289 	.seg6_require_hmac	= 0,
290 #endif
291 	.enhanced_dad           = 1,
292 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
293 	.disable_policy		= 0,
294 	.rpl_seg_enabled	= 0,
295 };
296 
297 /* Check if link is ready: is it up and is a valid qdisc available */
298 static inline bool addrconf_link_ready(const struct net_device *dev)
299 {
300 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
301 }
302 
303 static void addrconf_del_rs_timer(struct inet6_dev *idev)
304 {
305 	if (del_timer(&idev->rs_timer))
306 		__in6_dev_put(idev);
307 }
308 
309 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
310 {
311 	if (cancel_delayed_work(&ifp->dad_work))
312 		__in6_ifa_put(ifp);
313 }
314 
315 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
316 				  unsigned long when)
317 {
318 	if (!timer_pending(&idev->rs_timer))
319 		in6_dev_hold(idev);
320 	mod_timer(&idev->rs_timer, jiffies + when);
321 }
322 
323 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
324 				   unsigned long delay)
325 {
326 	in6_ifa_hold(ifp);
327 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
328 		in6_ifa_put(ifp);
329 }
330 
331 static int snmp6_alloc_dev(struct inet6_dev *idev)
332 {
333 	int i;
334 
335 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
336 	if (!idev->stats.ipv6)
337 		goto err_ip;
338 
339 	for_each_possible_cpu(i) {
340 		struct ipstats_mib *addrconf_stats;
341 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
342 		u64_stats_init(&addrconf_stats->syncp);
343 	}
344 
345 
346 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
347 					GFP_KERNEL);
348 	if (!idev->stats.icmpv6dev)
349 		goto err_icmp;
350 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
351 					   GFP_KERNEL);
352 	if (!idev->stats.icmpv6msgdev)
353 		goto err_icmpmsg;
354 
355 	return 0;
356 
357 err_icmpmsg:
358 	kfree(idev->stats.icmpv6dev);
359 err_icmp:
360 	free_percpu(idev->stats.ipv6);
361 err_ip:
362 	return -ENOMEM;
363 }
364 
365 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
366 {
367 	struct inet6_dev *ndev;
368 	int err = -ENOMEM;
369 
370 	ASSERT_RTNL();
371 
372 	if (dev->mtu < IPV6_MIN_MTU)
373 		return ERR_PTR(-EINVAL);
374 
375 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
376 	if (!ndev)
377 		return ERR_PTR(err);
378 
379 	rwlock_init(&ndev->lock);
380 	ndev->dev = dev;
381 	INIT_LIST_HEAD(&ndev->addr_list);
382 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
383 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
384 
385 	if (ndev->cnf.stable_secret.initialized)
386 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
387 
388 	ndev->cnf.mtu6 = dev->mtu;
389 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
390 	if (!ndev->nd_parms) {
391 		kfree(ndev);
392 		return ERR_PTR(err);
393 	}
394 	if (ndev->cnf.forwarding)
395 		dev_disable_lro(dev);
396 	/* We refer to the device */
397 	dev_hold(dev);
398 
399 	if (snmp6_alloc_dev(ndev) < 0) {
400 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
401 			   __func__);
402 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
403 		dev_put(dev);
404 		kfree(ndev);
405 		return ERR_PTR(err);
406 	}
407 
408 	if (snmp6_register_dev(ndev) < 0) {
409 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
410 			   __func__, dev->name);
411 		goto err_release;
412 	}
413 
414 	/* One reference from device. */
415 	refcount_set(&ndev->refcnt, 1);
416 
417 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
418 		ndev->cnf.accept_dad = -1;
419 
420 #if IS_ENABLED(CONFIG_IPV6_SIT)
421 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
422 		pr_info("%s: Disabled Multicast RS\n", dev->name);
423 		ndev->cnf.rtr_solicits = 0;
424 	}
425 #endif
426 
427 	INIT_LIST_HEAD(&ndev->tempaddr_list);
428 	ndev->desync_factor = U32_MAX;
429 	if ((dev->flags&IFF_LOOPBACK) ||
430 	    dev->type == ARPHRD_TUNNEL ||
431 	    dev->type == ARPHRD_TUNNEL6 ||
432 	    dev->type == ARPHRD_SIT ||
433 	    dev->type == ARPHRD_NONE) {
434 		ndev->cnf.use_tempaddr = -1;
435 	} else
436 		ipv6_regen_rndid(ndev);
437 
438 	ndev->token = in6addr_any;
439 
440 	if (netif_running(dev) && addrconf_link_ready(dev))
441 		ndev->if_flags |= IF_READY;
442 
443 	ipv6_mc_init_dev(ndev);
444 	ndev->tstamp = jiffies;
445 	err = addrconf_sysctl_register(ndev);
446 	if (err) {
447 		ipv6_mc_destroy_dev(ndev);
448 		snmp6_unregister_dev(ndev);
449 		goto err_release;
450 	}
451 	/* protected by rtnl_lock */
452 	rcu_assign_pointer(dev->ip6_ptr, ndev);
453 
454 	/* Join interface-local all-node multicast group */
455 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
456 
457 	/* Join all-node multicast group */
458 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
459 
460 	/* Join all-router multicast group if forwarding is set */
461 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
462 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
463 
464 	return ndev;
465 
466 err_release:
467 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
468 	ndev->dead = 1;
469 	in6_dev_finish_destroy(ndev);
470 	return ERR_PTR(err);
471 }
472 
473 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
474 {
475 	struct inet6_dev *idev;
476 
477 	ASSERT_RTNL();
478 
479 	idev = __in6_dev_get(dev);
480 	if (!idev) {
481 		idev = ipv6_add_dev(dev);
482 		if (IS_ERR(idev))
483 			return idev;
484 	}
485 
486 	if (dev->flags&IFF_UP)
487 		ipv6_mc_up(idev);
488 	return idev;
489 }
490 
491 static int inet6_netconf_msgsize_devconf(int type)
492 {
493 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
494 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
495 	bool all = false;
496 
497 	if (type == NETCONFA_ALL)
498 		all = true;
499 
500 	if (all || type == NETCONFA_FORWARDING)
501 		size += nla_total_size(4);
502 #ifdef CONFIG_IPV6_MROUTE
503 	if (all || type == NETCONFA_MC_FORWARDING)
504 		size += nla_total_size(4);
505 #endif
506 	if (all || type == NETCONFA_PROXY_NEIGH)
507 		size += nla_total_size(4);
508 
509 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
510 		size += nla_total_size(4);
511 
512 	return size;
513 }
514 
515 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
516 				      struct ipv6_devconf *devconf, u32 portid,
517 				      u32 seq, int event, unsigned int flags,
518 				      int type)
519 {
520 	struct nlmsghdr  *nlh;
521 	struct netconfmsg *ncm;
522 	bool all = false;
523 
524 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
525 			flags);
526 	if (!nlh)
527 		return -EMSGSIZE;
528 
529 	if (type == NETCONFA_ALL)
530 		all = true;
531 
532 	ncm = nlmsg_data(nlh);
533 	ncm->ncm_family = AF_INET6;
534 
535 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
536 		goto nla_put_failure;
537 
538 	if (!devconf)
539 		goto out;
540 
541 	if ((all || type == NETCONFA_FORWARDING) &&
542 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
543 		goto nla_put_failure;
544 #ifdef CONFIG_IPV6_MROUTE
545 	if ((all || type == NETCONFA_MC_FORWARDING) &&
546 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
547 			devconf->mc_forwarding) < 0)
548 		goto nla_put_failure;
549 #endif
550 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
551 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
552 		goto nla_put_failure;
553 
554 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
555 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
556 			devconf->ignore_routes_with_linkdown) < 0)
557 		goto nla_put_failure;
558 
559 out:
560 	nlmsg_end(skb, nlh);
561 	return 0;
562 
563 nla_put_failure:
564 	nlmsg_cancel(skb, nlh);
565 	return -EMSGSIZE;
566 }
567 
568 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
569 				  int ifindex, struct ipv6_devconf *devconf)
570 {
571 	struct sk_buff *skb;
572 	int err = -ENOBUFS;
573 
574 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
575 	if (!skb)
576 		goto errout;
577 
578 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
579 					 event, 0, type);
580 	if (err < 0) {
581 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
582 		WARN_ON(err == -EMSGSIZE);
583 		kfree_skb(skb);
584 		goto errout;
585 	}
586 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
587 	return;
588 errout:
589 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
590 }
591 
592 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
593 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
594 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
595 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
596 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
597 };
598 
599 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
600 				       const struct nlmsghdr *nlh,
601 				       struct nlattr **tb,
602 				       struct netlink_ext_ack *extack)
603 {
604 	int i, err;
605 
606 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
607 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
608 		return -EINVAL;
609 	}
610 
611 	if (!netlink_strict_get_check(skb))
612 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
613 					      tb, NETCONFA_MAX,
614 					      devconf_ipv6_policy, extack);
615 
616 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
617 					    tb, NETCONFA_MAX,
618 					    devconf_ipv6_policy, extack);
619 	if (err)
620 		return err;
621 
622 	for (i = 0; i <= NETCONFA_MAX; i++) {
623 		if (!tb[i])
624 			continue;
625 
626 		switch (i) {
627 		case NETCONFA_IFINDEX:
628 			break;
629 		default:
630 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
631 			return -EINVAL;
632 		}
633 	}
634 
635 	return 0;
636 }
637 
638 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
639 				     struct nlmsghdr *nlh,
640 				     struct netlink_ext_ack *extack)
641 {
642 	struct net *net = sock_net(in_skb->sk);
643 	struct nlattr *tb[NETCONFA_MAX+1];
644 	struct inet6_dev *in6_dev = NULL;
645 	struct net_device *dev = NULL;
646 	struct sk_buff *skb;
647 	struct ipv6_devconf *devconf;
648 	int ifindex;
649 	int err;
650 
651 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
652 	if (err < 0)
653 		return err;
654 
655 	if (!tb[NETCONFA_IFINDEX])
656 		return -EINVAL;
657 
658 	err = -EINVAL;
659 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
660 	switch (ifindex) {
661 	case NETCONFA_IFINDEX_ALL:
662 		devconf = net->ipv6.devconf_all;
663 		break;
664 	case NETCONFA_IFINDEX_DEFAULT:
665 		devconf = net->ipv6.devconf_dflt;
666 		break;
667 	default:
668 		dev = dev_get_by_index(net, ifindex);
669 		if (!dev)
670 			return -EINVAL;
671 		in6_dev = in6_dev_get(dev);
672 		if (!in6_dev)
673 			goto errout;
674 		devconf = &in6_dev->cnf;
675 		break;
676 	}
677 
678 	err = -ENOBUFS;
679 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
680 	if (!skb)
681 		goto errout;
682 
683 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
684 					 NETLINK_CB(in_skb).portid,
685 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
686 					 NETCONFA_ALL);
687 	if (err < 0) {
688 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
689 		WARN_ON(err == -EMSGSIZE);
690 		kfree_skb(skb);
691 		goto errout;
692 	}
693 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
694 errout:
695 	if (in6_dev)
696 		in6_dev_put(in6_dev);
697 	if (dev)
698 		dev_put(dev);
699 	return err;
700 }
701 
702 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
703 				      struct netlink_callback *cb)
704 {
705 	const struct nlmsghdr *nlh = cb->nlh;
706 	struct net *net = sock_net(skb->sk);
707 	int h, s_h;
708 	int idx, s_idx;
709 	struct net_device *dev;
710 	struct inet6_dev *idev;
711 	struct hlist_head *head;
712 
713 	if (cb->strict_check) {
714 		struct netlink_ext_ack *extack = cb->extack;
715 		struct netconfmsg *ncm;
716 
717 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
718 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
719 			return -EINVAL;
720 		}
721 
722 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
723 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
724 			return -EINVAL;
725 		}
726 	}
727 
728 	s_h = cb->args[0];
729 	s_idx = idx = cb->args[1];
730 
731 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
732 		idx = 0;
733 		head = &net->dev_index_head[h];
734 		rcu_read_lock();
735 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
736 			  net->dev_base_seq;
737 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
738 			if (idx < s_idx)
739 				goto cont;
740 			idev = __in6_dev_get(dev);
741 			if (!idev)
742 				goto cont;
743 
744 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
745 						       &idev->cnf,
746 						       NETLINK_CB(cb->skb).portid,
747 						       nlh->nlmsg_seq,
748 						       RTM_NEWNETCONF,
749 						       NLM_F_MULTI,
750 						       NETCONFA_ALL) < 0) {
751 				rcu_read_unlock();
752 				goto done;
753 			}
754 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
755 cont:
756 			idx++;
757 		}
758 		rcu_read_unlock();
759 	}
760 	if (h == NETDEV_HASHENTRIES) {
761 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
762 					       net->ipv6.devconf_all,
763 					       NETLINK_CB(cb->skb).portid,
764 					       nlh->nlmsg_seq,
765 					       RTM_NEWNETCONF, NLM_F_MULTI,
766 					       NETCONFA_ALL) < 0)
767 			goto done;
768 		else
769 			h++;
770 	}
771 	if (h == NETDEV_HASHENTRIES + 1) {
772 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
773 					       net->ipv6.devconf_dflt,
774 					       NETLINK_CB(cb->skb).portid,
775 					       nlh->nlmsg_seq,
776 					       RTM_NEWNETCONF, NLM_F_MULTI,
777 					       NETCONFA_ALL) < 0)
778 			goto done;
779 		else
780 			h++;
781 	}
782 done:
783 	cb->args[0] = h;
784 	cb->args[1] = idx;
785 
786 	return skb->len;
787 }
788 
789 #ifdef CONFIG_SYSCTL
790 static void dev_forward_change(struct inet6_dev *idev)
791 {
792 	struct net_device *dev;
793 	struct inet6_ifaddr *ifa;
794 
795 	if (!idev)
796 		return;
797 	dev = idev->dev;
798 	if (idev->cnf.forwarding)
799 		dev_disable_lro(dev);
800 	if (dev->flags & IFF_MULTICAST) {
801 		if (idev->cnf.forwarding) {
802 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
803 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
804 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
805 		} else {
806 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
807 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
808 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
809 		}
810 	}
811 
812 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
813 		if (ifa->flags&IFA_F_TENTATIVE)
814 			continue;
815 		if (idev->cnf.forwarding)
816 			addrconf_join_anycast(ifa);
817 		else
818 			addrconf_leave_anycast(ifa);
819 	}
820 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
821 				     NETCONFA_FORWARDING,
822 				     dev->ifindex, &idev->cnf);
823 }
824 
825 
826 static void addrconf_forward_change(struct net *net, __s32 newf)
827 {
828 	struct net_device *dev;
829 	struct inet6_dev *idev;
830 
831 	for_each_netdev(net, dev) {
832 		idev = __in6_dev_get(dev);
833 		if (idev) {
834 			int changed = (!idev->cnf.forwarding) ^ (!newf);
835 			idev->cnf.forwarding = newf;
836 			if (changed)
837 				dev_forward_change(idev);
838 		}
839 	}
840 }
841 
842 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
843 {
844 	struct net *net;
845 	int old;
846 
847 	if (!rtnl_trylock())
848 		return restart_syscall();
849 
850 	net = (struct net *)table->extra2;
851 	old = *p;
852 	*p = newf;
853 
854 	if (p == &net->ipv6.devconf_dflt->forwarding) {
855 		if ((!newf) ^ (!old))
856 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
857 						     NETCONFA_FORWARDING,
858 						     NETCONFA_IFINDEX_DEFAULT,
859 						     net->ipv6.devconf_dflt);
860 		rtnl_unlock();
861 		return 0;
862 	}
863 
864 	if (p == &net->ipv6.devconf_all->forwarding) {
865 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
866 
867 		net->ipv6.devconf_dflt->forwarding = newf;
868 		if ((!newf) ^ (!old_dflt))
869 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
870 						     NETCONFA_FORWARDING,
871 						     NETCONFA_IFINDEX_DEFAULT,
872 						     net->ipv6.devconf_dflt);
873 
874 		addrconf_forward_change(net, newf);
875 		if ((!newf) ^ (!old))
876 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
877 						     NETCONFA_FORWARDING,
878 						     NETCONFA_IFINDEX_ALL,
879 						     net->ipv6.devconf_all);
880 	} else if ((!newf) ^ (!old))
881 		dev_forward_change((struct inet6_dev *)table->extra1);
882 	rtnl_unlock();
883 
884 	if (newf)
885 		rt6_purge_dflt_routers(net);
886 	return 1;
887 }
888 
889 static void addrconf_linkdown_change(struct net *net, __s32 newf)
890 {
891 	struct net_device *dev;
892 	struct inet6_dev *idev;
893 
894 	for_each_netdev(net, dev) {
895 		idev = __in6_dev_get(dev);
896 		if (idev) {
897 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
898 
899 			idev->cnf.ignore_routes_with_linkdown = newf;
900 			if (changed)
901 				inet6_netconf_notify_devconf(dev_net(dev),
902 							     RTM_NEWNETCONF,
903 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
904 							     dev->ifindex,
905 							     &idev->cnf);
906 		}
907 	}
908 }
909 
910 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
911 {
912 	struct net *net;
913 	int old;
914 
915 	if (!rtnl_trylock())
916 		return restart_syscall();
917 
918 	net = (struct net *)table->extra2;
919 	old = *p;
920 	*p = newf;
921 
922 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
923 		if ((!newf) ^ (!old))
924 			inet6_netconf_notify_devconf(net,
925 						     RTM_NEWNETCONF,
926 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
927 						     NETCONFA_IFINDEX_DEFAULT,
928 						     net->ipv6.devconf_dflt);
929 		rtnl_unlock();
930 		return 0;
931 	}
932 
933 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
934 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
935 		addrconf_linkdown_change(net, newf);
936 		if ((!newf) ^ (!old))
937 			inet6_netconf_notify_devconf(net,
938 						     RTM_NEWNETCONF,
939 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
940 						     NETCONFA_IFINDEX_ALL,
941 						     net->ipv6.devconf_all);
942 	}
943 	rtnl_unlock();
944 
945 	return 1;
946 }
947 
948 #endif
949 
950 /* Nobody refers to this ifaddr, destroy it */
951 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
952 {
953 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
954 
955 #ifdef NET_REFCNT_DEBUG
956 	pr_debug("%s\n", __func__);
957 #endif
958 
959 	in6_dev_put(ifp->idev);
960 
961 	if (cancel_delayed_work(&ifp->dad_work))
962 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
963 			  ifp);
964 
965 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
966 		pr_warn("Freeing alive inet6 address %p\n", ifp);
967 		return;
968 	}
969 
970 	kfree_rcu(ifp, rcu);
971 }
972 
973 static void
974 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
975 {
976 	struct list_head *p;
977 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
978 
979 	/*
980 	 * Each device address list is sorted in order of scope -
981 	 * global before linklocal.
982 	 */
983 	list_for_each(p, &idev->addr_list) {
984 		struct inet6_ifaddr *ifa
985 			= list_entry(p, struct inet6_ifaddr, if_list);
986 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
987 			break;
988 	}
989 
990 	list_add_tail_rcu(&ifp->if_list, p);
991 }
992 
993 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
994 {
995 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
996 
997 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
998 }
999 
1000 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1001 			       struct net_device *dev, unsigned int hash)
1002 {
1003 	struct inet6_ifaddr *ifp;
1004 
1005 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1006 		if (!net_eq(dev_net(ifp->idev->dev), net))
1007 			continue;
1008 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1009 			if (!dev || ifp->idev->dev == dev)
1010 				return true;
1011 		}
1012 	}
1013 	return false;
1014 }
1015 
1016 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1017 {
1018 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1019 	int err = 0;
1020 
1021 	spin_lock(&addrconf_hash_lock);
1022 
1023 	/* Ignore adding duplicate addresses on an interface */
1024 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1025 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1026 		err = -EEXIST;
1027 	} else {
1028 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1029 	}
1030 
1031 	spin_unlock(&addrconf_hash_lock);
1032 
1033 	return err;
1034 }
1035 
1036 /* On success it returns ifp with increased reference count */
1037 
1038 static struct inet6_ifaddr *
1039 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1040 	      bool can_block, struct netlink_ext_ack *extack)
1041 {
1042 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1043 	int addr_type = ipv6_addr_type(cfg->pfx);
1044 	struct net *net = dev_net(idev->dev);
1045 	struct inet6_ifaddr *ifa = NULL;
1046 	struct fib6_info *f6i = NULL;
1047 	int err = 0;
1048 
1049 	if (addr_type == IPV6_ADDR_ANY ||
1050 	    (addr_type & IPV6_ADDR_MULTICAST &&
1051 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1052 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1053 	     !netif_is_l3_master(idev->dev) &&
1054 	     addr_type & IPV6_ADDR_LOOPBACK))
1055 		return ERR_PTR(-EADDRNOTAVAIL);
1056 
1057 	if (idev->dead) {
1058 		err = -ENODEV;			/*XXX*/
1059 		goto out;
1060 	}
1061 
1062 	if (idev->cnf.disable_ipv6) {
1063 		err = -EACCES;
1064 		goto out;
1065 	}
1066 
1067 	/* validator notifier needs to be blocking;
1068 	 * do not call in atomic context
1069 	 */
1070 	if (can_block) {
1071 		struct in6_validator_info i6vi = {
1072 			.i6vi_addr = *cfg->pfx,
1073 			.i6vi_dev = idev,
1074 			.extack = extack,
1075 		};
1076 
1077 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1078 		err = notifier_to_errno(err);
1079 		if (err < 0)
1080 			goto out;
1081 	}
1082 
1083 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1084 	if (!ifa) {
1085 		err = -ENOBUFS;
1086 		goto out;
1087 	}
1088 
1089 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1090 	if (IS_ERR(f6i)) {
1091 		err = PTR_ERR(f6i);
1092 		f6i = NULL;
1093 		goto out;
1094 	}
1095 
1096 	if (net->ipv6.devconf_all->disable_policy ||
1097 	    idev->cnf.disable_policy)
1098 		f6i->dst_nopolicy = true;
1099 
1100 	neigh_parms_data_state_setall(idev->nd_parms);
1101 
1102 	ifa->addr = *cfg->pfx;
1103 	if (cfg->peer_pfx)
1104 		ifa->peer_addr = *cfg->peer_pfx;
1105 
1106 	spin_lock_init(&ifa->lock);
1107 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1108 	INIT_HLIST_NODE(&ifa->addr_lst);
1109 	ifa->scope = cfg->scope;
1110 	ifa->prefix_len = cfg->plen;
1111 	ifa->rt_priority = cfg->rt_priority;
1112 	ifa->flags = cfg->ifa_flags;
1113 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1114 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1115 		ifa->flags |= IFA_F_TENTATIVE;
1116 	ifa->valid_lft = cfg->valid_lft;
1117 	ifa->prefered_lft = cfg->preferred_lft;
1118 	ifa->cstamp = ifa->tstamp = jiffies;
1119 	ifa->tokenized = false;
1120 
1121 	ifa->rt = f6i;
1122 
1123 	ifa->idev = idev;
1124 	in6_dev_hold(idev);
1125 
1126 	/* For caller */
1127 	refcount_set(&ifa->refcnt, 1);
1128 
1129 	rcu_read_lock_bh();
1130 
1131 	err = ipv6_add_addr_hash(idev->dev, ifa);
1132 	if (err < 0) {
1133 		rcu_read_unlock_bh();
1134 		goto out;
1135 	}
1136 
1137 	write_lock(&idev->lock);
1138 
1139 	/* Add to inet6_dev unicast addr list. */
1140 	ipv6_link_dev_addr(idev, ifa);
1141 
1142 	if (ifa->flags&IFA_F_TEMPORARY) {
1143 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1144 		in6_ifa_hold(ifa);
1145 	}
1146 
1147 	in6_ifa_hold(ifa);
1148 	write_unlock(&idev->lock);
1149 
1150 	rcu_read_unlock_bh();
1151 
1152 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1153 out:
1154 	if (unlikely(err < 0)) {
1155 		fib6_info_release(f6i);
1156 
1157 		if (ifa) {
1158 			if (ifa->idev)
1159 				in6_dev_put(ifa->idev);
1160 			kfree(ifa);
1161 		}
1162 		ifa = ERR_PTR(err);
1163 	}
1164 
1165 	return ifa;
1166 }
1167 
1168 enum cleanup_prefix_rt_t {
1169 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1170 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1171 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1172 };
1173 
1174 /*
1175  * Check, whether the prefix for ifp would still need a prefix route
1176  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1177  * constants.
1178  *
1179  * 1) we don't purge prefix if address was not permanent.
1180  *    prefix is managed by its own lifetime.
1181  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1182  * 3) if there are no addresses, delete prefix.
1183  * 4) if there are still other permanent address(es),
1184  *    corresponding prefix is still permanent.
1185  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1186  *    don't purge the prefix, assume user space is managing it.
1187  * 6) otherwise, update prefix lifetime to the
1188  *    longest valid lifetime among the corresponding
1189  *    addresses on the device.
1190  *    Note: subsequent RA will update lifetime.
1191  **/
1192 static enum cleanup_prefix_rt_t
1193 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1194 {
1195 	struct inet6_ifaddr *ifa;
1196 	struct inet6_dev *idev = ifp->idev;
1197 	unsigned long lifetime;
1198 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1199 
1200 	*expires = jiffies;
1201 
1202 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1203 		if (ifa == ifp)
1204 			continue;
1205 		if (ifa->prefix_len != ifp->prefix_len ||
1206 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1207 				       ifp->prefix_len))
1208 			continue;
1209 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1210 			return CLEANUP_PREFIX_RT_NOP;
1211 
1212 		action = CLEANUP_PREFIX_RT_EXPIRE;
1213 
1214 		spin_lock(&ifa->lock);
1215 
1216 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1217 		/*
1218 		 * Note: Because this address is
1219 		 * not permanent, lifetime <
1220 		 * LONG_MAX / HZ here.
1221 		 */
1222 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1223 			*expires = ifa->tstamp + lifetime * HZ;
1224 		spin_unlock(&ifa->lock);
1225 	}
1226 
1227 	return action;
1228 }
1229 
1230 static void
1231 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1232 		     bool del_rt, bool del_peer)
1233 {
1234 	struct fib6_info *f6i;
1235 
1236 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1237 					ifp->prefix_len,
1238 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1239 	if (f6i) {
1240 		if (del_rt)
1241 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1242 		else {
1243 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1244 				fib6_set_expires(f6i, expires);
1245 			fib6_info_release(f6i);
1246 		}
1247 	}
1248 }
1249 
1250 
1251 /* This function wants to get referenced ifp and releases it before return */
1252 
1253 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1254 {
1255 	int state;
1256 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1257 	unsigned long expires;
1258 
1259 	ASSERT_RTNL();
1260 
1261 	spin_lock_bh(&ifp->lock);
1262 	state = ifp->state;
1263 	ifp->state = INET6_IFADDR_STATE_DEAD;
1264 	spin_unlock_bh(&ifp->lock);
1265 
1266 	if (state == INET6_IFADDR_STATE_DEAD)
1267 		goto out;
1268 
1269 	spin_lock_bh(&addrconf_hash_lock);
1270 	hlist_del_init_rcu(&ifp->addr_lst);
1271 	spin_unlock_bh(&addrconf_hash_lock);
1272 
1273 	write_lock_bh(&ifp->idev->lock);
1274 
1275 	if (ifp->flags&IFA_F_TEMPORARY) {
1276 		list_del(&ifp->tmp_list);
1277 		if (ifp->ifpub) {
1278 			in6_ifa_put(ifp->ifpub);
1279 			ifp->ifpub = NULL;
1280 		}
1281 		__in6_ifa_put(ifp);
1282 	}
1283 
1284 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1285 		action = check_cleanup_prefix_route(ifp, &expires);
1286 
1287 	list_del_rcu(&ifp->if_list);
1288 	__in6_ifa_put(ifp);
1289 
1290 	write_unlock_bh(&ifp->idev->lock);
1291 
1292 	addrconf_del_dad_work(ifp);
1293 
1294 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1295 
1296 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1297 
1298 	if (action != CLEANUP_PREFIX_RT_NOP) {
1299 		cleanup_prefix_route(ifp, expires,
1300 			action == CLEANUP_PREFIX_RT_DEL, false);
1301 	}
1302 
1303 	/* clean up prefsrc entries */
1304 	rt6_remove_prefsrc(ifp);
1305 out:
1306 	in6_ifa_put(ifp);
1307 }
1308 
1309 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1310 				struct inet6_ifaddr *ift,
1311 				bool block)
1312 {
1313 	struct inet6_dev *idev = ifp->idev;
1314 	struct in6_addr addr, *tmpaddr;
1315 	unsigned long tmp_tstamp, age;
1316 	unsigned long regen_advance;
1317 	struct ifa6_config cfg;
1318 	int ret = 0;
1319 	unsigned long now = jiffies;
1320 	long max_desync_factor;
1321 	s32 cnf_temp_preferred_lft;
1322 
1323 	write_lock_bh(&idev->lock);
1324 	if (ift) {
1325 		spin_lock_bh(&ift->lock);
1326 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1327 		spin_unlock_bh(&ift->lock);
1328 		tmpaddr = &addr;
1329 	} else {
1330 		tmpaddr = NULL;
1331 	}
1332 retry:
1333 	in6_dev_hold(idev);
1334 	if (idev->cnf.use_tempaddr <= 0) {
1335 		write_unlock_bh(&idev->lock);
1336 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1337 		in6_dev_put(idev);
1338 		ret = -1;
1339 		goto out;
1340 	}
1341 	spin_lock_bh(&ifp->lock);
1342 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1343 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1344 		spin_unlock_bh(&ifp->lock);
1345 		write_unlock_bh(&idev->lock);
1346 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1347 			__func__);
1348 		in6_dev_put(idev);
1349 		ret = -1;
1350 		goto out;
1351 	}
1352 	in6_ifa_hold(ifp);
1353 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1354 	ipv6_try_regen_rndid(idev, tmpaddr);
1355 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1356 	age = (now - ifp->tstamp) / HZ;
1357 
1358 	regen_advance = idev->cnf.regen_max_retry *
1359 			idev->cnf.dad_transmits *
1360 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1361 
1362 	/* recalculate max_desync_factor each time and update
1363 	 * idev->desync_factor if it's larger
1364 	 */
1365 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1366 	max_desync_factor = min_t(__u32,
1367 				  idev->cnf.max_desync_factor,
1368 				  cnf_temp_preferred_lft - regen_advance);
1369 
1370 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1371 		if (max_desync_factor > 0) {
1372 			get_random_bytes(&idev->desync_factor,
1373 					 sizeof(idev->desync_factor));
1374 			idev->desync_factor %= max_desync_factor;
1375 		} else {
1376 			idev->desync_factor = 0;
1377 		}
1378 	}
1379 
1380 	memset(&cfg, 0, sizeof(cfg));
1381 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1382 			      idev->cnf.temp_valid_lft + age);
1383 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1384 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1385 
1386 	cfg.plen = ifp->prefix_len;
1387 	tmp_tstamp = ifp->tstamp;
1388 	spin_unlock_bh(&ifp->lock);
1389 
1390 	write_unlock_bh(&idev->lock);
1391 
1392 	/* A temporary address is created only if this calculated Preferred
1393 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1394 	 * an implementation must not create a temporary address with a zero
1395 	 * Preferred Lifetime.
1396 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1397 	 * temporary addresses being generated.
1398 	 */
1399 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1400 	if (cfg.preferred_lft <= regen_advance + age) {
1401 		in6_ifa_put(ifp);
1402 		in6_dev_put(idev);
1403 		ret = -1;
1404 		goto out;
1405 	}
1406 
1407 	cfg.ifa_flags = IFA_F_TEMPORARY;
1408 	/* set in addrconf_prefix_rcv() */
1409 	if (ifp->flags & IFA_F_OPTIMISTIC)
1410 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1411 
1412 	cfg.pfx = &addr;
1413 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1414 
1415 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1416 	if (IS_ERR(ift)) {
1417 		in6_ifa_put(ifp);
1418 		in6_dev_put(idev);
1419 		pr_info("%s: retry temporary address regeneration\n", __func__);
1420 		tmpaddr = &addr;
1421 		write_lock_bh(&idev->lock);
1422 		goto retry;
1423 	}
1424 
1425 	spin_lock_bh(&ift->lock);
1426 	ift->ifpub = ifp;
1427 	ift->cstamp = now;
1428 	ift->tstamp = tmp_tstamp;
1429 	spin_unlock_bh(&ift->lock);
1430 
1431 	addrconf_dad_start(ift);
1432 	in6_ifa_put(ift);
1433 	in6_dev_put(idev);
1434 out:
1435 	return ret;
1436 }
1437 
1438 /*
1439  *	Choose an appropriate source address (RFC3484)
1440  */
1441 enum {
1442 	IPV6_SADDR_RULE_INIT = 0,
1443 	IPV6_SADDR_RULE_LOCAL,
1444 	IPV6_SADDR_RULE_SCOPE,
1445 	IPV6_SADDR_RULE_PREFERRED,
1446 #ifdef CONFIG_IPV6_MIP6
1447 	IPV6_SADDR_RULE_HOA,
1448 #endif
1449 	IPV6_SADDR_RULE_OIF,
1450 	IPV6_SADDR_RULE_LABEL,
1451 	IPV6_SADDR_RULE_PRIVACY,
1452 	IPV6_SADDR_RULE_ORCHID,
1453 	IPV6_SADDR_RULE_PREFIX,
1454 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1455 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1456 #endif
1457 	IPV6_SADDR_RULE_MAX
1458 };
1459 
1460 struct ipv6_saddr_score {
1461 	int			rule;
1462 	int			addr_type;
1463 	struct inet6_ifaddr	*ifa;
1464 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1465 	int			scopedist;
1466 	int			matchlen;
1467 };
1468 
1469 struct ipv6_saddr_dst {
1470 	const struct in6_addr *addr;
1471 	int ifindex;
1472 	int scope;
1473 	int label;
1474 	unsigned int prefs;
1475 };
1476 
1477 static inline int ipv6_saddr_preferred(int type)
1478 {
1479 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1480 		return 1;
1481 	return 0;
1482 }
1483 
1484 static bool ipv6_use_optimistic_addr(struct net *net,
1485 				     struct inet6_dev *idev)
1486 {
1487 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1488 	if (!idev)
1489 		return false;
1490 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1491 		return false;
1492 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1493 		return false;
1494 
1495 	return true;
1496 #else
1497 	return false;
1498 #endif
1499 }
1500 
1501 static bool ipv6_allow_optimistic_dad(struct net *net,
1502 				      struct inet6_dev *idev)
1503 {
1504 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1505 	if (!idev)
1506 		return false;
1507 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1508 		return false;
1509 
1510 	return true;
1511 #else
1512 	return false;
1513 #endif
1514 }
1515 
1516 static int ipv6_get_saddr_eval(struct net *net,
1517 			       struct ipv6_saddr_score *score,
1518 			       struct ipv6_saddr_dst *dst,
1519 			       int i)
1520 {
1521 	int ret;
1522 
1523 	if (i <= score->rule) {
1524 		switch (i) {
1525 		case IPV6_SADDR_RULE_SCOPE:
1526 			ret = score->scopedist;
1527 			break;
1528 		case IPV6_SADDR_RULE_PREFIX:
1529 			ret = score->matchlen;
1530 			break;
1531 		default:
1532 			ret = !!test_bit(i, score->scorebits);
1533 		}
1534 		goto out;
1535 	}
1536 
1537 	switch (i) {
1538 	case IPV6_SADDR_RULE_INIT:
1539 		/* Rule 0: remember if hiscore is not ready yet */
1540 		ret = !!score->ifa;
1541 		break;
1542 	case IPV6_SADDR_RULE_LOCAL:
1543 		/* Rule 1: Prefer same address */
1544 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1545 		break;
1546 	case IPV6_SADDR_RULE_SCOPE:
1547 		/* Rule 2: Prefer appropriate scope
1548 		 *
1549 		 *      ret
1550 		 *       ^
1551 		 *    -1 |  d 15
1552 		 *    ---+--+-+---> scope
1553 		 *       |
1554 		 *       |             d is scope of the destination.
1555 		 *  B-d  |  \
1556 		 *       |   \      <- smaller scope is better if
1557 		 *  B-15 |    \        if scope is enough for destination.
1558 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1559 		 * d-C-1 | /
1560 		 *       |/         <- greater is better
1561 		 *   -C  /             if scope is not enough for destination.
1562 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1563 		 *
1564 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1565 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1566 		 * Assume B = 0 and we get C > 29.
1567 		 */
1568 		ret = __ipv6_addr_src_scope(score->addr_type);
1569 		if (ret >= dst->scope)
1570 			ret = -ret;
1571 		else
1572 			ret -= 128;	/* 30 is enough */
1573 		score->scopedist = ret;
1574 		break;
1575 	case IPV6_SADDR_RULE_PREFERRED:
1576 	    {
1577 		/* Rule 3: Avoid deprecated and optimistic addresses */
1578 		u8 avoid = IFA_F_DEPRECATED;
1579 
1580 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1581 			avoid |= IFA_F_OPTIMISTIC;
1582 		ret = ipv6_saddr_preferred(score->addr_type) ||
1583 		      !(score->ifa->flags & avoid);
1584 		break;
1585 	    }
1586 #ifdef CONFIG_IPV6_MIP6
1587 	case IPV6_SADDR_RULE_HOA:
1588 	    {
1589 		/* Rule 4: Prefer home address */
1590 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1591 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1592 		break;
1593 	    }
1594 #endif
1595 	case IPV6_SADDR_RULE_OIF:
1596 		/* Rule 5: Prefer outgoing interface */
1597 		ret = (!dst->ifindex ||
1598 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1599 		break;
1600 	case IPV6_SADDR_RULE_LABEL:
1601 		/* Rule 6: Prefer matching label */
1602 		ret = ipv6_addr_label(net,
1603 				      &score->ifa->addr, score->addr_type,
1604 				      score->ifa->idev->dev->ifindex) == dst->label;
1605 		break;
1606 	case IPV6_SADDR_RULE_PRIVACY:
1607 	    {
1608 		/* Rule 7: Prefer public address
1609 		 * Note: prefer temporary address if use_tempaddr >= 2
1610 		 */
1611 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1612 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1613 				score->ifa->idev->cnf.use_tempaddr >= 2;
1614 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1615 		break;
1616 	    }
1617 	case IPV6_SADDR_RULE_ORCHID:
1618 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1619 		 *	    non-ORCHID vs non-ORCHID
1620 		 */
1621 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1622 			ipv6_addr_orchid(dst->addr));
1623 		break;
1624 	case IPV6_SADDR_RULE_PREFIX:
1625 		/* Rule 8: Use longest matching prefix */
1626 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1627 		if (ret > score->ifa->prefix_len)
1628 			ret = score->ifa->prefix_len;
1629 		score->matchlen = ret;
1630 		break;
1631 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1632 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1633 		/* Optimistic addresses still have lower precedence than other
1634 		 * preferred addresses.
1635 		 */
1636 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1637 		break;
1638 #endif
1639 	default:
1640 		ret = 0;
1641 	}
1642 
1643 	if (ret)
1644 		__set_bit(i, score->scorebits);
1645 	score->rule = i;
1646 out:
1647 	return ret;
1648 }
1649 
1650 static int __ipv6_dev_get_saddr(struct net *net,
1651 				struct ipv6_saddr_dst *dst,
1652 				struct inet6_dev *idev,
1653 				struct ipv6_saddr_score *scores,
1654 				int hiscore_idx)
1655 {
1656 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1657 
1658 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1659 		int i;
1660 
1661 		/*
1662 		 * - Tentative Address (RFC2462 section 5.4)
1663 		 *  - A tentative address is not considered
1664 		 *    "assigned to an interface" in the traditional
1665 		 *    sense, unless it is also flagged as optimistic.
1666 		 * - Candidate Source Address (section 4)
1667 		 *  - In any case, anycast addresses, multicast
1668 		 *    addresses, and the unspecified address MUST
1669 		 *    NOT be included in a candidate set.
1670 		 */
1671 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1672 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1673 			continue;
1674 
1675 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1676 
1677 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1678 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1679 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1680 					    idev->dev->name);
1681 			continue;
1682 		}
1683 
1684 		score->rule = -1;
1685 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1686 
1687 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1688 			int minihiscore, miniscore;
1689 
1690 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1691 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1692 
1693 			if (minihiscore > miniscore) {
1694 				if (i == IPV6_SADDR_RULE_SCOPE &&
1695 				    score->scopedist > 0) {
1696 					/*
1697 					 * special case:
1698 					 * each remaining entry
1699 					 * has too small (not enough)
1700 					 * scope, because ifa entries
1701 					 * are sorted by their scope
1702 					 * values.
1703 					 */
1704 					goto out;
1705 				}
1706 				break;
1707 			} else if (minihiscore < miniscore) {
1708 				swap(hiscore, score);
1709 				hiscore_idx = 1 - hiscore_idx;
1710 
1711 				/* restore our iterator */
1712 				score->ifa = hiscore->ifa;
1713 
1714 				break;
1715 			}
1716 		}
1717 	}
1718 out:
1719 	return hiscore_idx;
1720 }
1721 
1722 static int ipv6_get_saddr_master(struct net *net,
1723 				 const struct net_device *dst_dev,
1724 				 const struct net_device *master,
1725 				 struct ipv6_saddr_dst *dst,
1726 				 struct ipv6_saddr_score *scores,
1727 				 int hiscore_idx)
1728 {
1729 	struct inet6_dev *idev;
1730 
1731 	idev = __in6_dev_get(dst_dev);
1732 	if (idev)
1733 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1734 						   scores, hiscore_idx);
1735 
1736 	idev = __in6_dev_get(master);
1737 	if (idev)
1738 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1739 						   scores, hiscore_idx);
1740 
1741 	return hiscore_idx;
1742 }
1743 
1744 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1745 		       const struct in6_addr *daddr, unsigned int prefs,
1746 		       struct in6_addr *saddr)
1747 {
1748 	struct ipv6_saddr_score scores[2], *hiscore;
1749 	struct ipv6_saddr_dst dst;
1750 	struct inet6_dev *idev;
1751 	struct net_device *dev;
1752 	int dst_type;
1753 	bool use_oif_addr = false;
1754 	int hiscore_idx = 0;
1755 	int ret = 0;
1756 
1757 	dst_type = __ipv6_addr_type(daddr);
1758 	dst.addr = daddr;
1759 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1760 	dst.scope = __ipv6_addr_src_scope(dst_type);
1761 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1762 	dst.prefs = prefs;
1763 
1764 	scores[hiscore_idx].rule = -1;
1765 	scores[hiscore_idx].ifa = NULL;
1766 
1767 	rcu_read_lock();
1768 
1769 	/* Candidate Source Address (section 4)
1770 	 *  - multicast and link-local destination address,
1771 	 *    the set of candidate source address MUST only
1772 	 *    include addresses assigned to interfaces
1773 	 *    belonging to the same link as the outgoing
1774 	 *    interface.
1775 	 * (- For site-local destination addresses, the
1776 	 *    set of candidate source addresses MUST only
1777 	 *    include addresses assigned to interfaces
1778 	 *    belonging to the same site as the outgoing
1779 	 *    interface.)
1780 	 *  - "It is RECOMMENDED that the candidate source addresses
1781 	 *    be the set of unicast addresses assigned to the
1782 	 *    interface that will be used to send to the destination
1783 	 *    (the 'outgoing' interface)." (RFC 6724)
1784 	 */
1785 	if (dst_dev) {
1786 		idev = __in6_dev_get(dst_dev);
1787 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1788 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1789 		    (idev && idev->cnf.use_oif_addrs_only)) {
1790 			use_oif_addr = true;
1791 		}
1792 	}
1793 
1794 	if (use_oif_addr) {
1795 		if (idev)
1796 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1797 	} else {
1798 		const struct net_device *master;
1799 		int master_idx = 0;
1800 
1801 		/* if dst_dev exists and is enslaved to an L3 device, then
1802 		 * prefer addresses from dst_dev and then the master over
1803 		 * any other enslaved devices in the L3 domain.
1804 		 */
1805 		master = l3mdev_master_dev_rcu(dst_dev);
1806 		if (master) {
1807 			master_idx = master->ifindex;
1808 
1809 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1810 							    master, &dst,
1811 							    scores, hiscore_idx);
1812 
1813 			if (scores[hiscore_idx].ifa)
1814 				goto out;
1815 		}
1816 
1817 		for_each_netdev_rcu(net, dev) {
1818 			/* only consider addresses on devices in the
1819 			 * same L3 domain
1820 			 */
1821 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1822 				continue;
1823 			idev = __in6_dev_get(dev);
1824 			if (!idev)
1825 				continue;
1826 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1827 		}
1828 	}
1829 
1830 out:
1831 	hiscore = &scores[hiscore_idx];
1832 	if (!hiscore->ifa)
1833 		ret = -EADDRNOTAVAIL;
1834 	else
1835 		*saddr = hiscore->ifa->addr;
1836 
1837 	rcu_read_unlock();
1838 	return ret;
1839 }
1840 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1841 
1842 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1843 		      u32 banned_flags)
1844 {
1845 	struct inet6_ifaddr *ifp;
1846 	int err = -EADDRNOTAVAIL;
1847 
1848 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1849 		if (ifp->scope > IFA_LINK)
1850 			break;
1851 		if (ifp->scope == IFA_LINK &&
1852 		    !(ifp->flags & banned_flags)) {
1853 			*addr = ifp->addr;
1854 			err = 0;
1855 			break;
1856 		}
1857 	}
1858 	return err;
1859 }
1860 
1861 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1862 		    u32 banned_flags)
1863 {
1864 	struct inet6_dev *idev;
1865 	int err = -EADDRNOTAVAIL;
1866 
1867 	rcu_read_lock();
1868 	idev = __in6_dev_get(dev);
1869 	if (idev) {
1870 		read_lock_bh(&idev->lock);
1871 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1872 		read_unlock_bh(&idev->lock);
1873 	}
1874 	rcu_read_unlock();
1875 	return err;
1876 }
1877 
1878 static int ipv6_count_addresses(const struct inet6_dev *idev)
1879 {
1880 	const struct inet6_ifaddr *ifp;
1881 	int cnt = 0;
1882 
1883 	rcu_read_lock();
1884 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1885 		cnt++;
1886 	rcu_read_unlock();
1887 	return cnt;
1888 }
1889 
1890 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1891 		  const struct net_device *dev, int strict)
1892 {
1893 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1894 				       strict, IFA_F_TENTATIVE);
1895 }
1896 EXPORT_SYMBOL(ipv6_chk_addr);
1897 
1898 /* device argument is used to find the L3 domain of interest. If
1899  * skip_dev_check is set, then the ifp device is not checked against
1900  * the passed in dev argument. So the 2 cases for addresses checks are:
1901  *   1. does the address exist in the L3 domain that dev is part of
1902  *      (skip_dev_check = true), or
1903  *
1904  *   2. does the address exist on the specific device
1905  *      (skip_dev_check = false)
1906  */
1907 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1908 			    const struct net_device *dev, bool skip_dev_check,
1909 			    int strict, u32 banned_flags)
1910 {
1911 	unsigned int hash = inet6_addr_hash(net, addr);
1912 	const struct net_device *l3mdev;
1913 	struct inet6_ifaddr *ifp;
1914 	u32 ifp_flags;
1915 
1916 	rcu_read_lock();
1917 
1918 	l3mdev = l3mdev_master_dev_rcu(dev);
1919 	if (skip_dev_check)
1920 		dev = NULL;
1921 
1922 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1923 		if (!net_eq(dev_net(ifp->idev->dev), net))
1924 			continue;
1925 
1926 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1927 			continue;
1928 
1929 		/* Decouple optimistic from tentative for evaluation here.
1930 		 * Ban optimistic addresses explicitly, when required.
1931 		 */
1932 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1933 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1934 			    : ifp->flags;
1935 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1936 		    !(ifp_flags&banned_flags) &&
1937 		    (!dev || ifp->idev->dev == dev ||
1938 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1939 			rcu_read_unlock();
1940 			return 1;
1941 		}
1942 	}
1943 
1944 	rcu_read_unlock();
1945 	return 0;
1946 }
1947 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1948 
1949 
1950 /* Compares an address/prefix_len with addresses on device @dev.
1951  * If one is found it returns true.
1952  */
1953 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1954 	const unsigned int prefix_len, struct net_device *dev)
1955 {
1956 	const struct inet6_ifaddr *ifa;
1957 	const struct inet6_dev *idev;
1958 	bool ret = false;
1959 
1960 	rcu_read_lock();
1961 	idev = __in6_dev_get(dev);
1962 	if (idev) {
1963 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1964 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1965 			if (ret)
1966 				break;
1967 		}
1968 	}
1969 	rcu_read_unlock();
1970 
1971 	return ret;
1972 }
1973 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1974 
1975 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1976 {
1977 	const struct inet6_ifaddr *ifa;
1978 	const struct inet6_dev *idev;
1979 	int	onlink;
1980 
1981 	onlink = 0;
1982 	rcu_read_lock();
1983 	idev = __in6_dev_get(dev);
1984 	if (idev) {
1985 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1986 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1987 						   ifa->prefix_len);
1988 			if (onlink)
1989 				break;
1990 		}
1991 	}
1992 	rcu_read_unlock();
1993 	return onlink;
1994 }
1995 EXPORT_SYMBOL(ipv6_chk_prefix);
1996 
1997 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1998 				     struct net_device *dev, int strict)
1999 {
2000 	unsigned int hash = inet6_addr_hash(net, addr);
2001 	struct inet6_ifaddr *ifp, *result = NULL;
2002 
2003 	rcu_read_lock();
2004 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2005 		if (!net_eq(dev_net(ifp->idev->dev), net))
2006 			continue;
2007 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2008 			if (!dev || ifp->idev->dev == dev ||
2009 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2010 				result = ifp;
2011 				in6_ifa_hold(ifp);
2012 				break;
2013 			}
2014 		}
2015 	}
2016 	rcu_read_unlock();
2017 
2018 	return result;
2019 }
2020 
2021 /* Gets referenced address, destroys ifaddr */
2022 
2023 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2024 {
2025 	if (dad_failed)
2026 		ifp->flags |= IFA_F_DADFAILED;
2027 
2028 	if (ifp->flags&IFA_F_TEMPORARY) {
2029 		struct inet6_ifaddr *ifpub;
2030 		spin_lock_bh(&ifp->lock);
2031 		ifpub = ifp->ifpub;
2032 		if (ifpub) {
2033 			in6_ifa_hold(ifpub);
2034 			spin_unlock_bh(&ifp->lock);
2035 			ipv6_create_tempaddr(ifpub, ifp, true);
2036 			in6_ifa_put(ifpub);
2037 		} else {
2038 			spin_unlock_bh(&ifp->lock);
2039 		}
2040 		ipv6_del_addr(ifp);
2041 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2042 		spin_lock_bh(&ifp->lock);
2043 		addrconf_del_dad_work(ifp);
2044 		ifp->flags |= IFA_F_TENTATIVE;
2045 		if (dad_failed)
2046 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2047 		spin_unlock_bh(&ifp->lock);
2048 		if (dad_failed)
2049 			ipv6_ifa_notify(0, ifp);
2050 		in6_ifa_put(ifp);
2051 	} else {
2052 		ipv6_del_addr(ifp);
2053 	}
2054 }
2055 
2056 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2057 {
2058 	int err = -ENOENT;
2059 
2060 	spin_lock_bh(&ifp->lock);
2061 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2062 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2063 		err = 0;
2064 	}
2065 	spin_unlock_bh(&ifp->lock);
2066 
2067 	return err;
2068 }
2069 
2070 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2071 {
2072 	struct inet6_dev *idev = ifp->idev;
2073 	struct net *net = dev_net(ifp->idev->dev);
2074 
2075 	if (addrconf_dad_end(ifp)) {
2076 		in6_ifa_put(ifp);
2077 		return;
2078 	}
2079 
2080 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2081 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2082 
2083 	spin_lock_bh(&ifp->lock);
2084 
2085 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2086 		struct in6_addr new_addr;
2087 		struct inet6_ifaddr *ifp2;
2088 		int retries = ifp->stable_privacy_retry + 1;
2089 		struct ifa6_config cfg = {
2090 			.pfx = &new_addr,
2091 			.plen = ifp->prefix_len,
2092 			.ifa_flags = ifp->flags,
2093 			.valid_lft = ifp->valid_lft,
2094 			.preferred_lft = ifp->prefered_lft,
2095 			.scope = ifp->scope,
2096 		};
2097 
2098 		if (retries > net->ipv6.sysctl.idgen_retries) {
2099 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2100 					     ifp->idev->dev->name);
2101 			goto errdad;
2102 		}
2103 
2104 		new_addr = ifp->addr;
2105 		if (ipv6_generate_stable_address(&new_addr, retries,
2106 						 idev))
2107 			goto errdad;
2108 
2109 		spin_unlock_bh(&ifp->lock);
2110 
2111 		if (idev->cnf.max_addresses &&
2112 		    ipv6_count_addresses(idev) >=
2113 		    idev->cnf.max_addresses)
2114 			goto lock_errdad;
2115 
2116 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2117 				     ifp->idev->dev->name);
2118 
2119 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2120 		if (IS_ERR(ifp2))
2121 			goto lock_errdad;
2122 
2123 		spin_lock_bh(&ifp2->lock);
2124 		ifp2->stable_privacy_retry = retries;
2125 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2126 		spin_unlock_bh(&ifp2->lock);
2127 
2128 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2129 		in6_ifa_put(ifp2);
2130 lock_errdad:
2131 		spin_lock_bh(&ifp->lock);
2132 	}
2133 
2134 errdad:
2135 	/* transition from _POSTDAD to _ERRDAD */
2136 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2137 	spin_unlock_bh(&ifp->lock);
2138 
2139 	addrconf_mod_dad_work(ifp, 0);
2140 	in6_ifa_put(ifp);
2141 }
2142 
2143 /* Join to solicited addr multicast group.
2144  * caller must hold RTNL */
2145 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2146 {
2147 	struct in6_addr maddr;
2148 
2149 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2150 		return;
2151 
2152 	addrconf_addr_solict_mult(addr, &maddr);
2153 	ipv6_dev_mc_inc(dev, &maddr);
2154 }
2155 
2156 /* caller must hold RTNL */
2157 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2158 {
2159 	struct in6_addr maddr;
2160 
2161 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2162 		return;
2163 
2164 	addrconf_addr_solict_mult(addr, &maddr);
2165 	__ipv6_dev_mc_dec(idev, &maddr);
2166 }
2167 
2168 /* caller must hold RTNL */
2169 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2170 {
2171 	struct in6_addr addr;
2172 
2173 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2174 		return;
2175 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2176 	if (ipv6_addr_any(&addr))
2177 		return;
2178 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2179 }
2180 
2181 /* caller must hold RTNL */
2182 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2183 {
2184 	struct in6_addr addr;
2185 
2186 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2187 		return;
2188 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2189 	if (ipv6_addr_any(&addr))
2190 		return;
2191 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2192 }
2193 
2194 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2195 {
2196 	switch (dev->addr_len) {
2197 	case ETH_ALEN:
2198 		memcpy(eui, dev->dev_addr, 3);
2199 		eui[3] = 0xFF;
2200 		eui[4] = 0xFE;
2201 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2202 		break;
2203 	case EUI64_ADDR_LEN:
2204 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2205 		eui[0] ^= 2;
2206 		break;
2207 	default:
2208 		return -1;
2209 	}
2210 
2211 	return 0;
2212 }
2213 
2214 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2215 {
2216 	union fwnet_hwaddr *ha;
2217 
2218 	if (dev->addr_len != FWNET_ALEN)
2219 		return -1;
2220 
2221 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2222 
2223 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2224 	eui[0] ^= 2;
2225 	return 0;
2226 }
2227 
2228 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2229 {
2230 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2231 	if (dev->addr_len != ARCNET_ALEN)
2232 		return -1;
2233 	memset(eui, 0, 7);
2234 	eui[7] = *(u8 *)dev->dev_addr;
2235 	return 0;
2236 }
2237 
2238 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2239 {
2240 	if (dev->addr_len != INFINIBAND_ALEN)
2241 		return -1;
2242 	memcpy(eui, dev->dev_addr + 12, 8);
2243 	eui[0] |= 2;
2244 	return 0;
2245 }
2246 
2247 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2248 {
2249 	if (addr == 0)
2250 		return -1;
2251 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2252 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2253 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2254 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2255 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2256 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2257 	eui[1] = 0;
2258 	eui[2] = 0x5E;
2259 	eui[3] = 0xFE;
2260 	memcpy(eui + 4, &addr, 4);
2261 	return 0;
2262 }
2263 
2264 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2265 {
2266 	if (dev->priv_flags & IFF_ISATAP)
2267 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2268 	return -1;
2269 }
2270 
2271 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2272 {
2273 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2274 }
2275 
2276 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2277 {
2278 	memcpy(eui, dev->perm_addr, 3);
2279 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2280 	eui[3] = 0xFF;
2281 	eui[4] = 0xFE;
2282 	eui[0] ^= 2;
2283 	return 0;
2284 }
2285 
2286 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2287 {
2288 	switch (dev->type) {
2289 	case ARPHRD_ETHER:
2290 	case ARPHRD_FDDI:
2291 		return addrconf_ifid_eui48(eui, dev);
2292 	case ARPHRD_ARCNET:
2293 		return addrconf_ifid_arcnet(eui, dev);
2294 	case ARPHRD_INFINIBAND:
2295 		return addrconf_ifid_infiniband(eui, dev);
2296 	case ARPHRD_SIT:
2297 		return addrconf_ifid_sit(eui, dev);
2298 	case ARPHRD_IPGRE:
2299 	case ARPHRD_TUNNEL:
2300 		return addrconf_ifid_gre(eui, dev);
2301 	case ARPHRD_6LOWPAN:
2302 		return addrconf_ifid_6lowpan(eui, dev);
2303 	case ARPHRD_IEEE1394:
2304 		return addrconf_ifid_ieee1394(eui, dev);
2305 	case ARPHRD_TUNNEL6:
2306 	case ARPHRD_IP6GRE:
2307 	case ARPHRD_RAWIP:
2308 		return addrconf_ifid_ip6tnl(eui, dev);
2309 	}
2310 	return -1;
2311 }
2312 
2313 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2314 {
2315 	int err = -1;
2316 	struct inet6_ifaddr *ifp;
2317 
2318 	read_lock_bh(&idev->lock);
2319 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2320 		if (ifp->scope > IFA_LINK)
2321 			break;
2322 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2323 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2324 			err = 0;
2325 			break;
2326 		}
2327 	}
2328 	read_unlock_bh(&idev->lock);
2329 	return err;
2330 }
2331 
2332 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2333 static void ipv6_regen_rndid(struct inet6_dev *idev)
2334 {
2335 regen:
2336 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2337 	idev->rndid[0] &= ~0x02;
2338 
2339 	/*
2340 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2341 	 * check if generated address is not inappropriate
2342 	 *
2343 	 *  - Reserved subnet anycast (RFC 2526)
2344 	 *	11111101 11....11 1xxxxxxx
2345 	 *  - ISATAP (RFC4214) 6.1
2346 	 *	00-00-5E-FE-xx-xx-xx-xx
2347 	 *  - value 0
2348 	 *  - XXX: already assigned to an address on the device
2349 	 */
2350 	if (idev->rndid[0] == 0xfd &&
2351 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2352 	    (idev->rndid[7]&0x80))
2353 		goto regen;
2354 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2355 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2356 			goto regen;
2357 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2358 			goto regen;
2359 	}
2360 }
2361 
2362 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2363 {
2364 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2365 		ipv6_regen_rndid(idev);
2366 }
2367 
2368 /*
2369  *	Add prefix route.
2370  */
2371 
2372 static void
2373 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2374 		      struct net_device *dev, unsigned long expires,
2375 		      u32 flags, gfp_t gfp_flags)
2376 {
2377 	struct fib6_config cfg = {
2378 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2379 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2380 		.fc_ifindex = dev->ifindex,
2381 		.fc_expires = expires,
2382 		.fc_dst_len = plen,
2383 		.fc_flags = RTF_UP | flags,
2384 		.fc_nlinfo.nl_net = dev_net(dev),
2385 		.fc_protocol = RTPROT_KERNEL,
2386 		.fc_type = RTN_UNICAST,
2387 	};
2388 
2389 	cfg.fc_dst = *pfx;
2390 
2391 	/* Prevent useless cloning on PtP SIT.
2392 	   This thing is done here expecting that the whole
2393 	   class of non-broadcast devices need not cloning.
2394 	 */
2395 #if IS_ENABLED(CONFIG_IPV6_SIT)
2396 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2397 		cfg.fc_flags |= RTF_NONEXTHOP;
2398 #endif
2399 
2400 	ip6_route_add(&cfg, gfp_flags, NULL);
2401 }
2402 
2403 
2404 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2405 						  int plen,
2406 						  const struct net_device *dev,
2407 						  u32 flags, u32 noflags,
2408 						  bool no_gw)
2409 {
2410 	struct fib6_node *fn;
2411 	struct fib6_info *rt = NULL;
2412 	struct fib6_table *table;
2413 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2414 
2415 	table = fib6_get_table(dev_net(dev), tb_id);
2416 	if (!table)
2417 		return NULL;
2418 
2419 	rcu_read_lock();
2420 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2421 	if (!fn)
2422 		goto out;
2423 
2424 	for_each_fib6_node_rt_rcu(fn) {
2425 		/* prefix routes only use builtin fib6_nh */
2426 		if (rt->nh)
2427 			continue;
2428 
2429 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2430 			continue;
2431 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2432 			continue;
2433 		if ((rt->fib6_flags & flags) != flags)
2434 			continue;
2435 		if ((rt->fib6_flags & noflags) != 0)
2436 			continue;
2437 		if (!fib6_info_hold_safe(rt))
2438 			continue;
2439 		break;
2440 	}
2441 out:
2442 	rcu_read_unlock();
2443 	return rt;
2444 }
2445 
2446 
2447 /* Create "default" multicast route to the interface */
2448 
2449 static void addrconf_add_mroute(struct net_device *dev)
2450 {
2451 	struct fib6_config cfg = {
2452 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2453 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2454 		.fc_ifindex = dev->ifindex,
2455 		.fc_dst_len = 8,
2456 		.fc_flags = RTF_UP,
2457 		.fc_type = RTN_UNICAST,
2458 		.fc_nlinfo.nl_net = dev_net(dev),
2459 	};
2460 
2461 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2462 
2463 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2464 }
2465 
2466 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2467 {
2468 	struct inet6_dev *idev;
2469 
2470 	ASSERT_RTNL();
2471 
2472 	idev = ipv6_find_idev(dev);
2473 	if (IS_ERR(idev))
2474 		return idev;
2475 
2476 	if (idev->cnf.disable_ipv6)
2477 		return ERR_PTR(-EACCES);
2478 
2479 	/* Add default multicast route */
2480 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2481 		addrconf_add_mroute(dev);
2482 
2483 	return idev;
2484 }
2485 
2486 static void manage_tempaddrs(struct inet6_dev *idev,
2487 			     struct inet6_ifaddr *ifp,
2488 			     __u32 valid_lft, __u32 prefered_lft,
2489 			     bool create, unsigned long now)
2490 {
2491 	u32 flags;
2492 	struct inet6_ifaddr *ift;
2493 
2494 	read_lock_bh(&idev->lock);
2495 	/* update all temporary addresses in the list */
2496 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2497 		int age, max_valid, max_prefered;
2498 
2499 		if (ifp != ift->ifpub)
2500 			continue;
2501 
2502 		/* RFC 4941 section 3.3:
2503 		 * If a received option will extend the lifetime of a public
2504 		 * address, the lifetimes of temporary addresses should
2505 		 * be extended, subject to the overall constraint that no
2506 		 * temporary addresses should ever remain "valid" or "preferred"
2507 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2508 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2509 		 */
2510 		age = (now - ift->cstamp) / HZ;
2511 		max_valid = idev->cnf.temp_valid_lft - age;
2512 		if (max_valid < 0)
2513 			max_valid = 0;
2514 
2515 		max_prefered = idev->cnf.temp_prefered_lft -
2516 			       idev->desync_factor - age;
2517 		if (max_prefered < 0)
2518 			max_prefered = 0;
2519 
2520 		if (valid_lft > max_valid)
2521 			valid_lft = max_valid;
2522 
2523 		if (prefered_lft > max_prefered)
2524 			prefered_lft = max_prefered;
2525 
2526 		spin_lock(&ift->lock);
2527 		flags = ift->flags;
2528 		ift->valid_lft = valid_lft;
2529 		ift->prefered_lft = prefered_lft;
2530 		ift->tstamp = now;
2531 		if (prefered_lft > 0)
2532 			ift->flags &= ~IFA_F_DEPRECATED;
2533 
2534 		spin_unlock(&ift->lock);
2535 		if (!(flags&IFA_F_TENTATIVE))
2536 			ipv6_ifa_notify(0, ift);
2537 	}
2538 
2539 	if ((create || list_empty(&idev->tempaddr_list)) &&
2540 	    idev->cnf.use_tempaddr > 0) {
2541 		/* When a new public address is created as described
2542 		 * in [ADDRCONF], also create a new temporary address.
2543 		 * Also create a temporary address if it's enabled but
2544 		 * no temporary address currently exists.
2545 		 */
2546 		read_unlock_bh(&idev->lock);
2547 		ipv6_create_tempaddr(ifp, NULL, false);
2548 	} else {
2549 		read_unlock_bh(&idev->lock);
2550 	}
2551 }
2552 
2553 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2554 {
2555 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2556 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2557 }
2558 
2559 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2560 				 const struct prefix_info *pinfo,
2561 				 struct inet6_dev *in6_dev,
2562 				 const struct in6_addr *addr, int addr_type,
2563 				 u32 addr_flags, bool sllao, bool tokenized,
2564 				 __u32 valid_lft, u32 prefered_lft)
2565 {
2566 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2567 	int create = 0;
2568 
2569 	if (!ifp && valid_lft) {
2570 		int max_addresses = in6_dev->cnf.max_addresses;
2571 		struct ifa6_config cfg = {
2572 			.pfx = addr,
2573 			.plen = pinfo->prefix_len,
2574 			.ifa_flags = addr_flags,
2575 			.valid_lft = valid_lft,
2576 			.preferred_lft = prefered_lft,
2577 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2578 		};
2579 
2580 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2581 		if ((net->ipv6.devconf_all->optimistic_dad ||
2582 		     in6_dev->cnf.optimistic_dad) &&
2583 		    !net->ipv6.devconf_all->forwarding && sllao)
2584 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2585 #endif
2586 
2587 		/* Do not allow to create too much of autoconfigured
2588 		 * addresses; this would be too easy way to crash kernel.
2589 		 */
2590 		if (!max_addresses ||
2591 		    ipv6_count_addresses(in6_dev) < max_addresses)
2592 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2593 
2594 		if (IS_ERR_OR_NULL(ifp))
2595 			return -1;
2596 
2597 		create = 1;
2598 		spin_lock_bh(&ifp->lock);
2599 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2600 		ifp->cstamp = jiffies;
2601 		ifp->tokenized = tokenized;
2602 		spin_unlock_bh(&ifp->lock);
2603 		addrconf_dad_start(ifp);
2604 	}
2605 
2606 	if (ifp) {
2607 		u32 flags;
2608 		unsigned long now;
2609 		u32 stored_lft;
2610 
2611 		/* Update lifetime (RFC4862 5.5.3 e)
2612 		 * We deviate from RFC4862 by honoring all Valid Lifetimes to
2613 		 * improve the reaction of SLAAC to renumbering events
2614 		 * (draft-gont-6man-slaac-renum-06, Section 4.2)
2615 		 */
2616 		spin_lock_bh(&ifp->lock);
2617 		now = jiffies;
2618 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2619 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2620 		else
2621 			stored_lft = 0;
2622 
2623 		if (!create && stored_lft) {
2624 			ifp->valid_lft = valid_lft;
2625 			ifp->prefered_lft = prefered_lft;
2626 			ifp->tstamp = now;
2627 			flags = ifp->flags;
2628 			ifp->flags &= ~IFA_F_DEPRECATED;
2629 			spin_unlock_bh(&ifp->lock);
2630 
2631 			if (!(flags&IFA_F_TENTATIVE))
2632 				ipv6_ifa_notify(0, ifp);
2633 		} else
2634 			spin_unlock_bh(&ifp->lock);
2635 
2636 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2637 				 create, now);
2638 
2639 		in6_ifa_put(ifp);
2640 		addrconf_verify();
2641 	}
2642 
2643 	return 0;
2644 }
2645 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2646 
2647 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2648 {
2649 	struct prefix_info *pinfo;
2650 	__u32 valid_lft;
2651 	__u32 prefered_lft;
2652 	int addr_type, err;
2653 	u32 addr_flags = 0;
2654 	struct inet6_dev *in6_dev;
2655 	struct net *net = dev_net(dev);
2656 
2657 	pinfo = (struct prefix_info *) opt;
2658 
2659 	if (len < sizeof(struct prefix_info)) {
2660 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2661 		return;
2662 	}
2663 
2664 	/*
2665 	 *	Validation checks ([ADDRCONF], page 19)
2666 	 */
2667 
2668 	addr_type = ipv6_addr_type(&pinfo->prefix);
2669 
2670 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2671 		return;
2672 
2673 	valid_lft = ntohl(pinfo->valid);
2674 	prefered_lft = ntohl(pinfo->prefered);
2675 
2676 	if (prefered_lft > valid_lft) {
2677 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2678 		return;
2679 	}
2680 
2681 	in6_dev = in6_dev_get(dev);
2682 
2683 	if (!in6_dev) {
2684 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2685 				    dev->name);
2686 		return;
2687 	}
2688 
2689 	/*
2690 	 *	Two things going on here:
2691 	 *	1) Add routes for on-link prefixes
2692 	 *	2) Configure prefixes with the auto flag set
2693 	 */
2694 
2695 	if (pinfo->onlink) {
2696 		struct fib6_info *rt;
2697 		unsigned long rt_expires;
2698 
2699 		/* Avoid arithmetic overflow. Really, we could
2700 		 * save rt_expires in seconds, likely valid_lft,
2701 		 * but it would require division in fib gc, that it
2702 		 * not good.
2703 		 */
2704 		if (HZ > USER_HZ)
2705 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2706 		else
2707 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2708 
2709 		if (addrconf_finite_timeout(rt_expires))
2710 			rt_expires *= HZ;
2711 
2712 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2713 					       pinfo->prefix_len,
2714 					       dev,
2715 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2716 					       RTF_DEFAULT, true);
2717 
2718 		if (rt) {
2719 			/* Autoconf prefix route */
2720 			if (valid_lft == 0) {
2721 				ip6_del_rt(net, rt, false);
2722 				rt = NULL;
2723 			} else if (addrconf_finite_timeout(rt_expires)) {
2724 				/* not infinity */
2725 				fib6_set_expires(rt, jiffies + rt_expires);
2726 			} else {
2727 				fib6_clean_expires(rt);
2728 			}
2729 		} else if (valid_lft) {
2730 			clock_t expires = 0;
2731 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2732 			if (addrconf_finite_timeout(rt_expires)) {
2733 				/* not infinity */
2734 				flags |= RTF_EXPIRES;
2735 				expires = jiffies_to_clock_t(rt_expires);
2736 			}
2737 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2738 					      0, dev, expires, flags,
2739 					      GFP_ATOMIC);
2740 		}
2741 		fib6_info_release(rt);
2742 	}
2743 
2744 	/* Try to figure out our local address for this prefix */
2745 
2746 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2747 		struct in6_addr addr;
2748 		bool tokenized = false, dev_addr_generated = false;
2749 
2750 		if (pinfo->prefix_len == 64) {
2751 			memcpy(&addr, &pinfo->prefix, 8);
2752 
2753 			if (!ipv6_addr_any(&in6_dev->token)) {
2754 				read_lock_bh(&in6_dev->lock);
2755 				memcpy(addr.s6_addr + 8,
2756 				       in6_dev->token.s6_addr + 8, 8);
2757 				read_unlock_bh(&in6_dev->lock);
2758 				tokenized = true;
2759 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2760 				   !ipv6_generate_stable_address(&addr, 0,
2761 								 in6_dev)) {
2762 				addr_flags |= IFA_F_STABLE_PRIVACY;
2763 				goto ok;
2764 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2765 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2766 				goto put;
2767 			} else {
2768 				dev_addr_generated = true;
2769 			}
2770 			goto ok;
2771 		}
2772 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2773 				    pinfo->prefix_len);
2774 		goto put;
2775 
2776 ok:
2777 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2778 						   &addr, addr_type,
2779 						   addr_flags, sllao,
2780 						   tokenized, valid_lft,
2781 						   prefered_lft);
2782 		if (err)
2783 			goto put;
2784 
2785 		/* Ignore error case here because previous prefix add addr was
2786 		 * successful which will be notified.
2787 		 */
2788 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2789 					      addr_type, addr_flags, sllao,
2790 					      tokenized, valid_lft,
2791 					      prefered_lft,
2792 					      dev_addr_generated);
2793 	}
2794 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2795 put:
2796 	in6_dev_put(in6_dev);
2797 }
2798 
2799 /*
2800  *	Set destination address.
2801  *	Special case for SIT interfaces where we create a new "virtual"
2802  *	device.
2803  */
2804 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2805 {
2806 	struct in6_ifreq ireq;
2807 	struct net_device *dev;
2808 	int err = -EINVAL;
2809 
2810 	rtnl_lock();
2811 
2812 	err = -EFAULT;
2813 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2814 		goto err_exit;
2815 
2816 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2817 
2818 	err = -ENODEV;
2819 	if (!dev)
2820 		goto err_exit;
2821 
2822 #if IS_ENABLED(CONFIG_IPV6_SIT)
2823 	if (dev->type == ARPHRD_SIT) {
2824 		const struct net_device_ops *ops = dev->netdev_ops;
2825 		struct ifreq ifr;
2826 		struct ip_tunnel_parm p;
2827 
2828 		err = -EADDRNOTAVAIL;
2829 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2830 			goto err_exit;
2831 
2832 		memset(&p, 0, sizeof(p));
2833 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2834 		p.iph.saddr = 0;
2835 		p.iph.version = 4;
2836 		p.iph.ihl = 5;
2837 		p.iph.protocol = IPPROTO_IPV6;
2838 		p.iph.ttl = 64;
2839 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2840 
2841 		if (ops->ndo_do_ioctl) {
2842 			mm_segment_t oldfs = get_fs();
2843 
2844 			set_fs(KERNEL_DS);
2845 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2846 			set_fs(oldfs);
2847 		} else
2848 			err = -EOPNOTSUPP;
2849 
2850 		if (err == 0) {
2851 			err = -ENOBUFS;
2852 			dev = __dev_get_by_name(net, p.name);
2853 			if (!dev)
2854 				goto err_exit;
2855 			err = dev_open(dev, NULL);
2856 		}
2857 	}
2858 #endif
2859 
2860 err_exit:
2861 	rtnl_unlock();
2862 	return err;
2863 }
2864 
2865 static int ipv6_mc_config(struct sock *sk, bool join,
2866 			  const struct in6_addr *addr, int ifindex)
2867 {
2868 	int ret;
2869 
2870 	ASSERT_RTNL();
2871 
2872 	lock_sock(sk);
2873 	if (join)
2874 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2875 	else
2876 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2877 	release_sock(sk);
2878 
2879 	return ret;
2880 }
2881 
2882 /*
2883  *	Manual configuration of address on an interface
2884  */
2885 static int inet6_addr_add(struct net *net, int ifindex,
2886 			  struct ifa6_config *cfg,
2887 			  struct netlink_ext_ack *extack)
2888 {
2889 	struct inet6_ifaddr *ifp;
2890 	struct inet6_dev *idev;
2891 	struct net_device *dev;
2892 	unsigned long timeout;
2893 	clock_t expires;
2894 	u32 flags;
2895 
2896 	ASSERT_RTNL();
2897 
2898 	if (cfg->plen > 128)
2899 		return -EINVAL;
2900 
2901 	/* check the lifetime */
2902 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2903 		return -EINVAL;
2904 
2905 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2906 		return -EINVAL;
2907 
2908 	dev = __dev_get_by_index(net, ifindex);
2909 	if (!dev)
2910 		return -ENODEV;
2911 
2912 	idev = addrconf_add_dev(dev);
2913 	if (IS_ERR(idev))
2914 		return PTR_ERR(idev);
2915 
2916 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2917 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2918 					 true, cfg->pfx, ifindex);
2919 
2920 		if (ret < 0)
2921 			return ret;
2922 	}
2923 
2924 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2925 
2926 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2927 	if (addrconf_finite_timeout(timeout)) {
2928 		expires = jiffies_to_clock_t(timeout * HZ);
2929 		cfg->valid_lft = timeout;
2930 		flags = RTF_EXPIRES;
2931 	} else {
2932 		expires = 0;
2933 		flags = 0;
2934 		cfg->ifa_flags |= IFA_F_PERMANENT;
2935 	}
2936 
2937 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2938 	if (addrconf_finite_timeout(timeout)) {
2939 		if (timeout == 0)
2940 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2941 		cfg->preferred_lft = timeout;
2942 	}
2943 
2944 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2945 	if (!IS_ERR(ifp)) {
2946 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2947 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2948 					      ifp->rt_priority, dev, expires,
2949 					      flags, GFP_KERNEL);
2950 		}
2951 
2952 		/* Send a netlink notification if DAD is enabled and
2953 		 * optimistic flag is not set
2954 		 */
2955 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2956 			ipv6_ifa_notify(0, ifp);
2957 		/*
2958 		 * Note that section 3.1 of RFC 4429 indicates
2959 		 * that the Optimistic flag should not be set for
2960 		 * manually configured addresses
2961 		 */
2962 		addrconf_dad_start(ifp);
2963 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2964 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2965 					 cfg->preferred_lft, true, jiffies);
2966 		in6_ifa_put(ifp);
2967 		addrconf_verify_rtnl();
2968 		return 0;
2969 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2970 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2971 			       cfg->pfx, ifindex);
2972 	}
2973 
2974 	return PTR_ERR(ifp);
2975 }
2976 
2977 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2978 			  const struct in6_addr *pfx, unsigned int plen)
2979 {
2980 	struct inet6_ifaddr *ifp;
2981 	struct inet6_dev *idev;
2982 	struct net_device *dev;
2983 
2984 	if (plen > 128)
2985 		return -EINVAL;
2986 
2987 	dev = __dev_get_by_index(net, ifindex);
2988 	if (!dev)
2989 		return -ENODEV;
2990 
2991 	idev = __in6_dev_get(dev);
2992 	if (!idev)
2993 		return -ENXIO;
2994 
2995 	read_lock_bh(&idev->lock);
2996 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2997 		if (ifp->prefix_len == plen &&
2998 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2999 			in6_ifa_hold(ifp);
3000 			read_unlock_bh(&idev->lock);
3001 
3002 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3003 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3004 				manage_tempaddrs(idev, ifp, 0, 0, false,
3005 						 jiffies);
3006 			ipv6_del_addr(ifp);
3007 			addrconf_verify_rtnl();
3008 			if (ipv6_addr_is_multicast(pfx)) {
3009 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3010 					       false, pfx, dev->ifindex);
3011 			}
3012 			return 0;
3013 		}
3014 	}
3015 	read_unlock_bh(&idev->lock);
3016 	return -EADDRNOTAVAIL;
3017 }
3018 
3019 
3020 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3021 {
3022 	struct ifa6_config cfg = {
3023 		.ifa_flags = IFA_F_PERMANENT,
3024 		.preferred_lft = INFINITY_LIFE_TIME,
3025 		.valid_lft = INFINITY_LIFE_TIME,
3026 	};
3027 	struct in6_ifreq ireq;
3028 	int err;
3029 
3030 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3031 		return -EPERM;
3032 
3033 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3034 		return -EFAULT;
3035 
3036 	cfg.pfx = &ireq.ifr6_addr;
3037 	cfg.plen = ireq.ifr6_prefixlen;
3038 
3039 	rtnl_lock();
3040 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3041 	rtnl_unlock();
3042 	return err;
3043 }
3044 
3045 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3046 {
3047 	struct in6_ifreq ireq;
3048 	int err;
3049 
3050 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3051 		return -EPERM;
3052 
3053 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3054 		return -EFAULT;
3055 
3056 	rtnl_lock();
3057 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3058 			     ireq.ifr6_prefixlen);
3059 	rtnl_unlock();
3060 	return err;
3061 }
3062 
3063 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3064 		     int plen, int scope)
3065 {
3066 	struct inet6_ifaddr *ifp;
3067 	struct ifa6_config cfg = {
3068 		.pfx = addr,
3069 		.plen = plen,
3070 		.ifa_flags = IFA_F_PERMANENT,
3071 		.valid_lft = INFINITY_LIFE_TIME,
3072 		.preferred_lft = INFINITY_LIFE_TIME,
3073 		.scope = scope
3074 	};
3075 
3076 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3077 	if (!IS_ERR(ifp)) {
3078 		spin_lock_bh(&ifp->lock);
3079 		ifp->flags &= ~IFA_F_TENTATIVE;
3080 		spin_unlock_bh(&ifp->lock);
3081 		rt_genid_bump_ipv6(dev_net(idev->dev));
3082 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3083 		in6_ifa_put(ifp);
3084 	}
3085 }
3086 
3087 #if IS_ENABLED(CONFIG_IPV6_SIT)
3088 static void sit_add_v4_addrs(struct inet6_dev *idev)
3089 {
3090 	struct in6_addr addr;
3091 	struct net_device *dev;
3092 	struct net *net = dev_net(idev->dev);
3093 	int scope, plen;
3094 	u32 pflags = 0;
3095 
3096 	ASSERT_RTNL();
3097 
3098 	memset(&addr, 0, sizeof(struct in6_addr));
3099 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3100 
3101 	if (idev->dev->flags&IFF_POINTOPOINT) {
3102 		addr.s6_addr32[0] = htonl(0xfe800000);
3103 		scope = IFA_LINK;
3104 		plen = 64;
3105 	} else {
3106 		scope = IPV6_ADDR_COMPATv4;
3107 		plen = 96;
3108 		pflags |= RTF_NONEXTHOP;
3109 	}
3110 
3111 	if (addr.s6_addr32[3]) {
3112 		add_addr(idev, &addr, plen, scope);
3113 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3114 				      GFP_KERNEL);
3115 		return;
3116 	}
3117 
3118 	for_each_netdev(net, dev) {
3119 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3120 		if (in_dev && (dev->flags & IFF_UP)) {
3121 			struct in_ifaddr *ifa;
3122 			int flag = scope;
3123 
3124 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3125 				addr.s6_addr32[3] = ifa->ifa_local;
3126 
3127 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3128 					continue;
3129 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3130 					if (idev->dev->flags&IFF_POINTOPOINT)
3131 						continue;
3132 					flag |= IFA_HOST;
3133 				}
3134 
3135 				add_addr(idev, &addr, plen, flag);
3136 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3137 						      0, pflags, GFP_KERNEL);
3138 			}
3139 		}
3140 	}
3141 }
3142 #endif
3143 
3144 static void init_loopback(struct net_device *dev)
3145 {
3146 	struct inet6_dev  *idev;
3147 
3148 	/* ::1 */
3149 
3150 	ASSERT_RTNL();
3151 
3152 	idev = ipv6_find_idev(dev);
3153 	if (IS_ERR(idev)) {
3154 		pr_debug("%s: add_dev failed\n", __func__);
3155 		return;
3156 	}
3157 
3158 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3159 }
3160 
3161 void addrconf_add_linklocal(struct inet6_dev *idev,
3162 			    const struct in6_addr *addr, u32 flags)
3163 {
3164 	struct ifa6_config cfg = {
3165 		.pfx = addr,
3166 		.plen = 64,
3167 		.ifa_flags = flags | IFA_F_PERMANENT,
3168 		.valid_lft = INFINITY_LIFE_TIME,
3169 		.preferred_lft = INFINITY_LIFE_TIME,
3170 		.scope = IFA_LINK
3171 	};
3172 	struct inet6_ifaddr *ifp;
3173 
3174 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3175 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3176 	     idev->cnf.optimistic_dad) &&
3177 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3178 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3179 #endif
3180 
3181 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3182 	if (!IS_ERR(ifp)) {
3183 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3184 				      0, 0, GFP_ATOMIC);
3185 		addrconf_dad_start(ifp);
3186 		in6_ifa_put(ifp);
3187 	}
3188 }
3189 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3190 
3191 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3192 {
3193 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3194 		return true;
3195 
3196 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3197 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3198 		return true;
3199 
3200 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3201 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3202 		return true;
3203 
3204 	return false;
3205 }
3206 
3207 static int ipv6_generate_stable_address(struct in6_addr *address,
3208 					u8 dad_count,
3209 					const struct inet6_dev *idev)
3210 {
3211 	static DEFINE_SPINLOCK(lock);
3212 	static __u32 digest[SHA_DIGEST_WORDS];
3213 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3214 
3215 	static union {
3216 		char __data[SHA_MESSAGE_BYTES];
3217 		struct {
3218 			struct in6_addr secret;
3219 			__be32 prefix[2];
3220 			unsigned char hwaddr[MAX_ADDR_LEN];
3221 			u8 dad_count;
3222 		} __packed;
3223 	} data;
3224 
3225 	struct in6_addr secret;
3226 	struct in6_addr temp;
3227 	struct net *net = dev_net(idev->dev);
3228 
3229 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3230 
3231 	if (idev->cnf.stable_secret.initialized)
3232 		secret = idev->cnf.stable_secret.secret;
3233 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3234 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3235 	else
3236 		return -1;
3237 
3238 retry:
3239 	spin_lock_bh(&lock);
3240 
3241 	sha_init(digest);
3242 	memset(&data, 0, sizeof(data));
3243 	memset(workspace, 0, sizeof(workspace));
3244 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3245 	data.prefix[0] = address->s6_addr32[0];
3246 	data.prefix[1] = address->s6_addr32[1];
3247 	data.secret = secret;
3248 	data.dad_count = dad_count;
3249 
3250 	sha_transform(digest, data.__data, workspace);
3251 
3252 	temp = *address;
3253 	temp.s6_addr32[2] = (__force __be32)digest[0];
3254 	temp.s6_addr32[3] = (__force __be32)digest[1];
3255 
3256 	spin_unlock_bh(&lock);
3257 
3258 	if (ipv6_reserved_interfaceid(temp)) {
3259 		dad_count++;
3260 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3261 			return -1;
3262 		goto retry;
3263 	}
3264 
3265 	*address = temp;
3266 	return 0;
3267 }
3268 
3269 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3270 {
3271 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3272 
3273 	if (s->initialized)
3274 		return;
3275 	s = &idev->cnf.stable_secret;
3276 	get_random_bytes(&s->secret, sizeof(s->secret));
3277 	s->initialized = true;
3278 }
3279 
3280 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3281 {
3282 	struct in6_addr addr;
3283 
3284 	/* no link local addresses on L3 master devices */
3285 	if (netif_is_l3_master(idev->dev))
3286 		return;
3287 
3288 	/* no link local addresses on devices flagged as slaves */
3289 	if (idev->dev->flags & IFF_SLAVE)
3290 		return;
3291 
3292 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3293 
3294 	switch (idev->cnf.addr_gen_mode) {
3295 	case IN6_ADDR_GEN_MODE_RANDOM:
3296 		ipv6_gen_mode_random_init(idev);
3297 		fallthrough;
3298 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3299 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3300 			addrconf_add_linklocal(idev, &addr,
3301 					       IFA_F_STABLE_PRIVACY);
3302 		else if (prefix_route)
3303 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3304 					      0, 0, GFP_KERNEL);
3305 		break;
3306 	case IN6_ADDR_GEN_MODE_EUI64:
3307 		/* addrconf_add_linklocal also adds a prefix_route and we
3308 		 * only need to care about prefix routes if ipv6_generate_eui64
3309 		 * couldn't generate one.
3310 		 */
3311 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3312 			addrconf_add_linklocal(idev, &addr, 0);
3313 		else if (prefix_route)
3314 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3315 					      0, 0, GFP_KERNEL);
3316 		break;
3317 	case IN6_ADDR_GEN_MODE_NONE:
3318 	default:
3319 		/* will not add any link local address */
3320 		break;
3321 	}
3322 }
3323 
3324 static void addrconf_dev_config(struct net_device *dev)
3325 {
3326 	struct inet6_dev *idev;
3327 
3328 	ASSERT_RTNL();
3329 
3330 	if ((dev->type != ARPHRD_ETHER) &&
3331 	    (dev->type != ARPHRD_FDDI) &&
3332 	    (dev->type != ARPHRD_ARCNET) &&
3333 	    (dev->type != ARPHRD_INFINIBAND) &&
3334 	    (dev->type != ARPHRD_IEEE1394) &&
3335 	    (dev->type != ARPHRD_TUNNEL6) &&
3336 	    (dev->type != ARPHRD_6LOWPAN) &&
3337 	    (dev->type != ARPHRD_IP6GRE) &&
3338 	    (dev->type != ARPHRD_IPGRE) &&
3339 	    (dev->type != ARPHRD_TUNNEL) &&
3340 	    (dev->type != ARPHRD_NONE) &&
3341 	    (dev->type != ARPHRD_RAWIP)) {
3342 		/* Alas, we support only Ethernet autoconfiguration. */
3343 		idev = __in6_dev_get(dev);
3344 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3345 		    dev->flags & IFF_MULTICAST)
3346 			ipv6_mc_up(idev);
3347 		return;
3348 	}
3349 
3350 	idev = addrconf_add_dev(dev);
3351 	if (IS_ERR(idev))
3352 		return;
3353 
3354 	/* this device type has no EUI support */
3355 	if (dev->type == ARPHRD_NONE &&
3356 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3357 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3358 
3359 	addrconf_addr_gen(idev, false);
3360 }
3361 
3362 #if IS_ENABLED(CONFIG_IPV6_SIT)
3363 static void addrconf_sit_config(struct net_device *dev)
3364 {
3365 	struct inet6_dev *idev;
3366 
3367 	ASSERT_RTNL();
3368 
3369 	/*
3370 	 * Configure the tunnel with one of our IPv4
3371 	 * addresses... we should configure all of
3372 	 * our v4 addrs in the tunnel
3373 	 */
3374 
3375 	idev = ipv6_find_idev(dev);
3376 	if (IS_ERR(idev)) {
3377 		pr_debug("%s: add_dev failed\n", __func__);
3378 		return;
3379 	}
3380 
3381 	if (dev->priv_flags & IFF_ISATAP) {
3382 		addrconf_addr_gen(idev, false);
3383 		return;
3384 	}
3385 
3386 	sit_add_v4_addrs(idev);
3387 
3388 	if (dev->flags&IFF_POINTOPOINT)
3389 		addrconf_add_mroute(dev);
3390 }
3391 #endif
3392 
3393 #if IS_ENABLED(CONFIG_NET_IPGRE)
3394 static void addrconf_gre_config(struct net_device *dev)
3395 {
3396 	struct inet6_dev *idev;
3397 
3398 	ASSERT_RTNL();
3399 
3400 	idev = ipv6_find_idev(dev);
3401 	if (IS_ERR(idev)) {
3402 		pr_debug("%s: add_dev failed\n", __func__);
3403 		return;
3404 	}
3405 
3406 	addrconf_addr_gen(idev, true);
3407 	if (dev->flags & IFF_POINTOPOINT)
3408 		addrconf_add_mroute(dev);
3409 }
3410 #endif
3411 
3412 static int fixup_permanent_addr(struct net *net,
3413 				struct inet6_dev *idev,
3414 				struct inet6_ifaddr *ifp)
3415 {
3416 	/* !fib6_node means the host route was removed from the
3417 	 * FIB, for example, if 'lo' device is taken down. In that
3418 	 * case regenerate the host route.
3419 	 */
3420 	if (!ifp->rt || !ifp->rt->fib6_node) {
3421 		struct fib6_info *f6i, *prev;
3422 
3423 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3424 					 GFP_ATOMIC);
3425 		if (IS_ERR(f6i))
3426 			return PTR_ERR(f6i);
3427 
3428 		/* ifp->rt can be accessed outside of rtnl */
3429 		spin_lock(&ifp->lock);
3430 		prev = ifp->rt;
3431 		ifp->rt = f6i;
3432 		spin_unlock(&ifp->lock);
3433 
3434 		fib6_info_release(prev);
3435 	}
3436 
3437 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3438 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3439 				      ifp->rt_priority, idev->dev, 0, 0,
3440 				      GFP_ATOMIC);
3441 	}
3442 
3443 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3444 		addrconf_dad_start(ifp);
3445 
3446 	return 0;
3447 }
3448 
3449 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3450 {
3451 	struct inet6_ifaddr *ifp, *tmp;
3452 	struct inet6_dev *idev;
3453 
3454 	idev = __in6_dev_get(dev);
3455 	if (!idev)
3456 		return;
3457 
3458 	write_lock_bh(&idev->lock);
3459 
3460 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3461 		if ((ifp->flags & IFA_F_PERMANENT) &&
3462 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3463 			write_unlock_bh(&idev->lock);
3464 			in6_ifa_hold(ifp);
3465 			ipv6_del_addr(ifp);
3466 			write_lock_bh(&idev->lock);
3467 
3468 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3469 					     idev->dev->name, &ifp->addr);
3470 		}
3471 	}
3472 
3473 	write_unlock_bh(&idev->lock);
3474 }
3475 
3476 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3477 			   void *ptr)
3478 {
3479 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3480 	struct netdev_notifier_change_info *change_info;
3481 	struct netdev_notifier_changeupper_info *info;
3482 	struct inet6_dev *idev = __in6_dev_get(dev);
3483 	struct net *net = dev_net(dev);
3484 	int run_pending = 0;
3485 	int err;
3486 
3487 	switch (event) {
3488 	case NETDEV_REGISTER:
3489 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3490 			idev = ipv6_add_dev(dev);
3491 			if (IS_ERR(idev))
3492 				return notifier_from_errno(PTR_ERR(idev));
3493 		}
3494 		break;
3495 
3496 	case NETDEV_CHANGEMTU:
3497 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3498 		if (dev->mtu < IPV6_MIN_MTU) {
3499 			addrconf_ifdown(dev, dev != net->loopback_dev);
3500 			break;
3501 		}
3502 
3503 		if (idev) {
3504 			rt6_mtu_change(dev, dev->mtu);
3505 			idev->cnf.mtu6 = dev->mtu;
3506 			break;
3507 		}
3508 
3509 		/* allocate new idev */
3510 		idev = ipv6_add_dev(dev);
3511 		if (IS_ERR(idev))
3512 			break;
3513 
3514 		/* device is still not ready */
3515 		if (!(idev->if_flags & IF_READY))
3516 			break;
3517 
3518 		run_pending = 1;
3519 		fallthrough;
3520 	case NETDEV_UP:
3521 	case NETDEV_CHANGE:
3522 		if (dev->flags & IFF_SLAVE)
3523 			break;
3524 
3525 		if (idev && idev->cnf.disable_ipv6)
3526 			break;
3527 
3528 		if (event == NETDEV_UP) {
3529 			/* restore routes for permanent addresses */
3530 			addrconf_permanent_addr(net, dev);
3531 
3532 			if (!addrconf_link_ready(dev)) {
3533 				/* device is not ready yet. */
3534 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3535 					 dev->name);
3536 				break;
3537 			}
3538 
3539 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3540 				idev = ipv6_add_dev(dev);
3541 
3542 			if (!IS_ERR_OR_NULL(idev)) {
3543 				idev->if_flags |= IF_READY;
3544 				run_pending = 1;
3545 			}
3546 		} else if (event == NETDEV_CHANGE) {
3547 			if (!addrconf_link_ready(dev)) {
3548 				/* device is still not ready. */
3549 				rt6_sync_down_dev(dev, event);
3550 				break;
3551 			}
3552 
3553 			if (!IS_ERR_OR_NULL(idev)) {
3554 				if (idev->if_flags & IF_READY) {
3555 					/* device is already configured -
3556 					 * but resend MLD reports, we might
3557 					 * have roamed and need to update
3558 					 * multicast snooping switches
3559 					 */
3560 					ipv6_mc_up(idev);
3561 					change_info = ptr;
3562 					if (change_info->flags_changed & IFF_NOARP)
3563 						addrconf_dad_run(idev, true);
3564 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3565 					break;
3566 				}
3567 				idev->if_flags |= IF_READY;
3568 			}
3569 
3570 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3571 				dev->name);
3572 
3573 			run_pending = 1;
3574 		}
3575 
3576 		switch (dev->type) {
3577 #if IS_ENABLED(CONFIG_IPV6_SIT)
3578 		case ARPHRD_SIT:
3579 			addrconf_sit_config(dev);
3580 			break;
3581 #endif
3582 #if IS_ENABLED(CONFIG_NET_IPGRE)
3583 		case ARPHRD_IPGRE:
3584 			addrconf_gre_config(dev);
3585 			break;
3586 #endif
3587 		case ARPHRD_LOOPBACK:
3588 			init_loopback(dev);
3589 			break;
3590 
3591 		default:
3592 			addrconf_dev_config(dev);
3593 			break;
3594 		}
3595 
3596 		if (!IS_ERR_OR_NULL(idev)) {
3597 			if (run_pending)
3598 				addrconf_dad_run(idev, false);
3599 
3600 			/* Device has an address by now */
3601 			rt6_sync_up(dev, RTNH_F_DEAD);
3602 
3603 			/*
3604 			 * If the MTU changed during the interface down,
3605 			 * when the interface up, the changed MTU must be
3606 			 * reflected in the idev as well as routers.
3607 			 */
3608 			if (idev->cnf.mtu6 != dev->mtu &&
3609 			    dev->mtu >= IPV6_MIN_MTU) {
3610 				rt6_mtu_change(dev, dev->mtu);
3611 				idev->cnf.mtu6 = dev->mtu;
3612 			}
3613 			idev->tstamp = jiffies;
3614 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3615 
3616 			/*
3617 			 * If the changed mtu during down is lower than
3618 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3619 			 */
3620 			if (dev->mtu < IPV6_MIN_MTU)
3621 				addrconf_ifdown(dev, dev != net->loopback_dev);
3622 		}
3623 		break;
3624 
3625 	case NETDEV_DOWN:
3626 	case NETDEV_UNREGISTER:
3627 		/*
3628 		 *	Remove all addresses from this interface.
3629 		 */
3630 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3631 		break;
3632 
3633 	case NETDEV_CHANGENAME:
3634 		if (idev) {
3635 			snmp6_unregister_dev(idev);
3636 			addrconf_sysctl_unregister(idev);
3637 			err = addrconf_sysctl_register(idev);
3638 			if (err)
3639 				return notifier_from_errno(err);
3640 			err = snmp6_register_dev(idev);
3641 			if (err) {
3642 				addrconf_sysctl_unregister(idev);
3643 				return notifier_from_errno(err);
3644 			}
3645 		}
3646 		break;
3647 
3648 	case NETDEV_PRE_TYPE_CHANGE:
3649 	case NETDEV_POST_TYPE_CHANGE:
3650 		if (idev)
3651 			addrconf_type_change(dev, event);
3652 		break;
3653 
3654 	case NETDEV_CHANGEUPPER:
3655 		info = ptr;
3656 
3657 		/* flush all routes if dev is linked to or unlinked from
3658 		 * an L3 master device (e.g., VRF)
3659 		 */
3660 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3661 			addrconf_ifdown(dev, 0);
3662 	}
3663 
3664 	return NOTIFY_OK;
3665 }
3666 
3667 /*
3668  *	addrconf module should be notified of a device going up
3669  */
3670 static struct notifier_block ipv6_dev_notf = {
3671 	.notifier_call = addrconf_notify,
3672 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3673 };
3674 
3675 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3676 {
3677 	struct inet6_dev *idev;
3678 	ASSERT_RTNL();
3679 
3680 	idev = __in6_dev_get(dev);
3681 
3682 	if (event == NETDEV_POST_TYPE_CHANGE)
3683 		ipv6_mc_remap(idev);
3684 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3685 		ipv6_mc_unmap(idev);
3686 }
3687 
3688 static bool addr_is_local(const struct in6_addr *addr)
3689 {
3690 	return ipv6_addr_type(addr) &
3691 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3692 }
3693 
3694 static int addrconf_ifdown(struct net_device *dev, int how)
3695 {
3696 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3697 	struct net *net = dev_net(dev);
3698 	struct inet6_dev *idev;
3699 	struct inet6_ifaddr *ifa, *tmp;
3700 	bool keep_addr = false;
3701 	int state, i;
3702 
3703 	ASSERT_RTNL();
3704 
3705 	rt6_disable_ip(dev, event);
3706 
3707 	idev = __in6_dev_get(dev);
3708 	if (!idev)
3709 		return -ENODEV;
3710 
3711 	/*
3712 	 * Step 1: remove reference to ipv6 device from parent device.
3713 	 *	   Do not dev_put!
3714 	 */
3715 	if (how) {
3716 		idev->dead = 1;
3717 
3718 		/* protected by rtnl_lock */
3719 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3720 
3721 		/* Step 1.5: remove snmp6 entry */
3722 		snmp6_unregister_dev(idev);
3723 
3724 	}
3725 
3726 	/* combine the user config with event to determine if permanent
3727 	 * addresses are to be removed from address hash table
3728 	 */
3729 	if (!how && !idev->cnf.disable_ipv6) {
3730 		/* aggregate the system setting and interface setting */
3731 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3732 
3733 		if (!_keep_addr)
3734 			_keep_addr = idev->cnf.keep_addr_on_down;
3735 
3736 		keep_addr = (_keep_addr > 0);
3737 	}
3738 
3739 	/* Step 2: clear hash table */
3740 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3741 		struct hlist_head *h = &inet6_addr_lst[i];
3742 
3743 		spin_lock_bh(&addrconf_hash_lock);
3744 restart:
3745 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3746 			if (ifa->idev == idev) {
3747 				addrconf_del_dad_work(ifa);
3748 				/* combined flag + permanent flag decide if
3749 				 * address is retained on a down event
3750 				 */
3751 				if (!keep_addr ||
3752 				    !(ifa->flags & IFA_F_PERMANENT) ||
3753 				    addr_is_local(&ifa->addr)) {
3754 					hlist_del_init_rcu(&ifa->addr_lst);
3755 					goto restart;
3756 				}
3757 			}
3758 		}
3759 		spin_unlock_bh(&addrconf_hash_lock);
3760 	}
3761 
3762 	write_lock_bh(&idev->lock);
3763 
3764 	addrconf_del_rs_timer(idev);
3765 
3766 	/* Step 2: clear flags for stateless addrconf */
3767 	if (!how)
3768 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3769 
3770 	/* Step 3: clear tempaddr list */
3771 	while (!list_empty(&idev->tempaddr_list)) {
3772 		ifa = list_first_entry(&idev->tempaddr_list,
3773 				       struct inet6_ifaddr, tmp_list);
3774 		list_del(&ifa->tmp_list);
3775 		write_unlock_bh(&idev->lock);
3776 		spin_lock_bh(&ifa->lock);
3777 
3778 		if (ifa->ifpub) {
3779 			in6_ifa_put(ifa->ifpub);
3780 			ifa->ifpub = NULL;
3781 		}
3782 		spin_unlock_bh(&ifa->lock);
3783 		in6_ifa_put(ifa);
3784 		write_lock_bh(&idev->lock);
3785 	}
3786 
3787 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3788 		struct fib6_info *rt = NULL;
3789 		bool keep;
3790 
3791 		addrconf_del_dad_work(ifa);
3792 
3793 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3794 			!addr_is_local(&ifa->addr);
3795 
3796 		write_unlock_bh(&idev->lock);
3797 		spin_lock_bh(&ifa->lock);
3798 
3799 		if (keep) {
3800 			/* set state to skip the notifier below */
3801 			state = INET6_IFADDR_STATE_DEAD;
3802 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3803 			if (!(ifa->flags & IFA_F_NODAD))
3804 				ifa->flags |= IFA_F_TENTATIVE;
3805 
3806 			rt = ifa->rt;
3807 			ifa->rt = NULL;
3808 		} else {
3809 			state = ifa->state;
3810 			ifa->state = INET6_IFADDR_STATE_DEAD;
3811 		}
3812 
3813 		spin_unlock_bh(&ifa->lock);
3814 
3815 		if (rt)
3816 			ip6_del_rt(net, rt, false);
3817 
3818 		if (state != INET6_IFADDR_STATE_DEAD) {
3819 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3820 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3821 		} else {
3822 			if (idev->cnf.forwarding)
3823 				addrconf_leave_anycast(ifa);
3824 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3825 		}
3826 
3827 		write_lock_bh(&idev->lock);
3828 		if (!keep) {
3829 			list_del_rcu(&ifa->if_list);
3830 			in6_ifa_put(ifa);
3831 		}
3832 	}
3833 
3834 	write_unlock_bh(&idev->lock);
3835 
3836 	/* Step 5: Discard anycast and multicast list */
3837 	if (how) {
3838 		ipv6_ac_destroy_dev(idev);
3839 		ipv6_mc_destroy_dev(idev);
3840 	} else {
3841 		ipv6_mc_down(idev);
3842 	}
3843 
3844 	idev->tstamp = jiffies;
3845 
3846 	/* Last: Shot the device (if unregistered) */
3847 	if (how) {
3848 		addrconf_sysctl_unregister(idev);
3849 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3850 		neigh_ifdown(&nd_tbl, dev);
3851 		in6_dev_put(idev);
3852 	}
3853 	return 0;
3854 }
3855 
3856 static void addrconf_rs_timer(struct timer_list *t)
3857 {
3858 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3859 	struct net_device *dev = idev->dev;
3860 	struct in6_addr lladdr;
3861 
3862 	write_lock(&idev->lock);
3863 	if (idev->dead || !(idev->if_flags & IF_READY))
3864 		goto out;
3865 
3866 	if (!ipv6_accept_ra(idev))
3867 		goto out;
3868 
3869 	/* Announcement received after solicitation was sent */
3870 	if (idev->if_flags & IF_RA_RCVD)
3871 		goto out;
3872 
3873 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3874 		write_unlock(&idev->lock);
3875 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3876 			ndisc_send_rs(dev, &lladdr,
3877 				      &in6addr_linklocal_allrouters);
3878 		else
3879 			goto put;
3880 
3881 		write_lock(&idev->lock);
3882 		idev->rs_interval = rfc3315_s14_backoff_update(
3883 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3884 		/* The wait after the last probe can be shorter */
3885 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3886 					     idev->cnf.rtr_solicits) ?
3887 				      idev->cnf.rtr_solicit_delay :
3888 				      idev->rs_interval);
3889 	} else {
3890 		/*
3891 		 * Note: we do not support deprecated "all on-link"
3892 		 * assumption any longer.
3893 		 */
3894 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3895 	}
3896 
3897 out:
3898 	write_unlock(&idev->lock);
3899 put:
3900 	in6_dev_put(idev);
3901 }
3902 
3903 /*
3904  *	Duplicate Address Detection
3905  */
3906 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3907 {
3908 	unsigned long rand_num;
3909 	struct inet6_dev *idev = ifp->idev;
3910 	u64 nonce;
3911 
3912 	if (ifp->flags & IFA_F_OPTIMISTIC)
3913 		rand_num = 0;
3914 	else
3915 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3916 
3917 	nonce = 0;
3918 	if (idev->cnf.enhanced_dad ||
3919 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3920 		do
3921 			get_random_bytes(&nonce, 6);
3922 		while (nonce == 0);
3923 	}
3924 	ifp->dad_nonce = nonce;
3925 	ifp->dad_probes = idev->cnf.dad_transmits;
3926 	addrconf_mod_dad_work(ifp, rand_num);
3927 }
3928 
3929 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3930 {
3931 	struct inet6_dev *idev = ifp->idev;
3932 	struct net_device *dev = idev->dev;
3933 	bool bump_id, notify = false;
3934 	struct net *net;
3935 
3936 	addrconf_join_solict(dev, &ifp->addr);
3937 
3938 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3939 
3940 	read_lock_bh(&idev->lock);
3941 	spin_lock(&ifp->lock);
3942 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3943 		goto out;
3944 
3945 	net = dev_net(dev);
3946 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3947 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3948 	     idev->cnf.accept_dad < 1) ||
3949 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3950 	    ifp->flags & IFA_F_NODAD) {
3951 		bool send_na = false;
3952 
3953 		if (ifp->flags & IFA_F_TENTATIVE &&
3954 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3955 			send_na = true;
3956 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3957 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3958 		spin_unlock(&ifp->lock);
3959 		read_unlock_bh(&idev->lock);
3960 
3961 		addrconf_dad_completed(ifp, bump_id, send_na);
3962 		return;
3963 	}
3964 
3965 	if (!(idev->if_flags & IF_READY)) {
3966 		spin_unlock(&ifp->lock);
3967 		read_unlock_bh(&idev->lock);
3968 		/*
3969 		 * If the device is not ready:
3970 		 * - keep it tentative if it is a permanent address.
3971 		 * - otherwise, kill it.
3972 		 */
3973 		in6_ifa_hold(ifp);
3974 		addrconf_dad_stop(ifp, 0);
3975 		return;
3976 	}
3977 
3978 	/*
3979 	 * Optimistic nodes can start receiving
3980 	 * Frames right away
3981 	 */
3982 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3983 		ip6_ins_rt(net, ifp->rt);
3984 		if (ipv6_use_optimistic_addr(net, idev)) {
3985 			/* Because optimistic nodes can use this address,
3986 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3987 			 */
3988 			notify = true;
3989 		}
3990 	}
3991 
3992 	addrconf_dad_kick(ifp);
3993 out:
3994 	spin_unlock(&ifp->lock);
3995 	read_unlock_bh(&idev->lock);
3996 	if (notify)
3997 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3998 }
3999 
4000 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4001 {
4002 	bool begin_dad = false;
4003 
4004 	spin_lock_bh(&ifp->lock);
4005 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4006 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4007 		begin_dad = true;
4008 	}
4009 	spin_unlock_bh(&ifp->lock);
4010 
4011 	if (begin_dad)
4012 		addrconf_mod_dad_work(ifp, 0);
4013 }
4014 
4015 static void addrconf_dad_work(struct work_struct *w)
4016 {
4017 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4018 						struct inet6_ifaddr,
4019 						dad_work);
4020 	struct inet6_dev *idev = ifp->idev;
4021 	bool bump_id, disable_ipv6 = false;
4022 	struct in6_addr mcaddr;
4023 
4024 	enum {
4025 		DAD_PROCESS,
4026 		DAD_BEGIN,
4027 		DAD_ABORT,
4028 	} action = DAD_PROCESS;
4029 
4030 	rtnl_lock();
4031 
4032 	spin_lock_bh(&ifp->lock);
4033 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4034 		action = DAD_BEGIN;
4035 		ifp->state = INET6_IFADDR_STATE_DAD;
4036 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4037 		action = DAD_ABORT;
4038 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4039 
4040 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4041 		     idev->cnf.accept_dad > 1) &&
4042 		    !idev->cnf.disable_ipv6 &&
4043 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4044 			struct in6_addr addr;
4045 
4046 			addr.s6_addr32[0] = htonl(0xfe800000);
4047 			addr.s6_addr32[1] = 0;
4048 
4049 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4050 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4051 				/* DAD failed for link-local based on MAC */
4052 				idev->cnf.disable_ipv6 = 1;
4053 
4054 				pr_info("%s: IPv6 being disabled!\n",
4055 					ifp->idev->dev->name);
4056 				disable_ipv6 = true;
4057 			}
4058 		}
4059 	}
4060 	spin_unlock_bh(&ifp->lock);
4061 
4062 	if (action == DAD_BEGIN) {
4063 		addrconf_dad_begin(ifp);
4064 		goto out;
4065 	} else if (action == DAD_ABORT) {
4066 		in6_ifa_hold(ifp);
4067 		addrconf_dad_stop(ifp, 1);
4068 		if (disable_ipv6)
4069 			addrconf_ifdown(idev->dev, 0);
4070 		goto out;
4071 	}
4072 
4073 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4074 		goto out;
4075 
4076 	write_lock_bh(&idev->lock);
4077 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4078 		write_unlock_bh(&idev->lock);
4079 		goto out;
4080 	}
4081 
4082 	spin_lock(&ifp->lock);
4083 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4084 		spin_unlock(&ifp->lock);
4085 		write_unlock_bh(&idev->lock);
4086 		goto out;
4087 	}
4088 
4089 	if (ifp->dad_probes == 0) {
4090 		bool send_na = false;
4091 
4092 		/*
4093 		 * DAD was successful
4094 		 */
4095 
4096 		if (ifp->flags & IFA_F_TENTATIVE &&
4097 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4098 			send_na = true;
4099 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4100 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4101 		spin_unlock(&ifp->lock);
4102 		write_unlock_bh(&idev->lock);
4103 
4104 		addrconf_dad_completed(ifp, bump_id, send_na);
4105 
4106 		goto out;
4107 	}
4108 
4109 	ifp->dad_probes--;
4110 	addrconf_mod_dad_work(ifp,
4111 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4112 				  HZ/100));
4113 	spin_unlock(&ifp->lock);
4114 	write_unlock_bh(&idev->lock);
4115 
4116 	/* send a neighbour solicitation for our addr */
4117 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4118 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4119 		      ifp->dad_nonce);
4120 out:
4121 	in6_ifa_put(ifp);
4122 	rtnl_unlock();
4123 }
4124 
4125 /* ifp->idev must be at least read locked */
4126 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4127 {
4128 	struct inet6_ifaddr *ifpiter;
4129 	struct inet6_dev *idev = ifp->idev;
4130 
4131 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4132 		if (ifpiter->scope > IFA_LINK)
4133 			break;
4134 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4135 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4136 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4137 		    IFA_F_PERMANENT)
4138 			return false;
4139 	}
4140 	return true;
4141 }
4142 
4143 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4144 				   bool send_na)
4145 {
4146 	struct net_device *dev = ifp->idev->dev;
4147 	struct in6_addr lladdr;
4148 	bool send_rs, send_mld;
4149 
4150 	addrconf_del_dad_work(ifp);
4151 
4152 	/*
4153 	 *	Configure the address for reception. Now it is valid.
4154 	 */
4155 
4156 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4157 
4158 	/* If added prefix is link local and we are prepared to process
4159 	   router advertisements, start sending router solicitations.
4160 	 */
4161 
4162 	read_lock_bh(&ifp->idev->lock);
4163 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4164 	send_rs = send_mld &&
4165 		  ipv6_accept_ra(ifp->idev) &&
4166 		  ifp->idev->cnf.rtr_solicits != 0 &&
4167 		  (dev->flags&IFF_LOOPBACK) == 0;
4168 	read_unlock_bh(&ifp->idev->lock);
4169 
4170 	/* While dad is in progress mld report's source address is in6_addrany.
4171 	 * Resend with proper ll now.
4172 	 */
4173 	if (send_mld)
4174 		ipv6_mc_dad_complete(ifp->idev);
4175 
4176 	/* send unsolicited NA if enabled */
4177 	if (send_na &&
4178 	    (ifp->idev->cnf.ndisc_notify ||
4179 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4180 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4181 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4182 			      /*solicited=*/ false, /*override=*/ true,
4183 			      /*inc_opt=*/ true);
4184 	}
4185 
4186 	if (send_rs) {
4187 		/*
4188 		 *	If a host as already performed a random delay
4189 		 *	[...] as part of DAD [...] there is no need
4190 		 *	to delay again before sending the first RS
4191 		 */
4192 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4193 			return;
4194 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4195 
4196 		write_lock_bh(&ifp->idev->lock);
4197 		spin_lock(&ifp->lock);
4198 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4199 			ifp->idev->cnf.rtr_solicit_interval);
4200 		ifp->idev->rs_probes = 1;
4201 		ifp->idev->if_flags |= IF_RS_SENT;
4202 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4203 		spin_unlock(&ifp->lock);
4204 		write_unlock_bh(&ifp->idev->lock);
4205 	}
4206 
4207 	if (bump_id)
4208 		rt_genid_bump_ipv6(dev_net(dev));
4209 
4210 	/* Make sure that a new temporary address will be created
4211 	 * before this temporary address becomes deprecated.
4212 	 */
4213 	if (ifp->flags & IFA_F_TEMPORARY)
4214 		addrconf_verify_rtnl();
4215 }
4216 
4217 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4218 {
4219 	struct inet6_ifaddr *ifp;
4220 
4221 	read_lock_bh(&idev->lock);
4222 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4223 		spin_lock(&ifp->lock);
4224 		if ((ifp->flags & IFA_F_TENTATIVE &&
4225 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4226 			if (restart)
4227 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4228 			addrconf_dad_kick(ifp);
4229 		}
4230 		spin_unlock(&ifp->lock);
4231 	}
4232 	read_unlock_bh(&idev->lock);
4233 }
4234 
4235 #ifdef CONFIG_PROC_FS
4236 struct if6_iter_state {
4237 	struct seq_net_private p;
4238 	int bucket;
4239 	int offset;
4240 };
4241 
4242 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4243 {
4244 	struct if6_iter_state *state = seq->private;
4245 	struct net *net = seq_file_net(seq);
4246 	struct inet6_ifaddr *ifa = NULL;
4247 	int p = 0;
4248 
4249 	/* initial bucket if pos is 0 */
4250 	if (pos == 0) {
4251 		state->bucket = 0;
4252 		state->offset = 0;
4253 	}
4254 
4255 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4256 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4257 					 addr_lst) {
4258 			if (!net_eq(dev_net(ifa->idev->dev), net))
4259 				continue;
4260 			/* sync with offset */
4261 			if (p < state->offset) {
4262 				p++;
4263 				continue;
4264 			}
4265 			return ifa;
4266 		}
4267 
4268 		/* prepare for next bucket */
4269 		state->offset = 0;
4270 		p = 0;
4271 	}
4272 	return NULL;
4273 }
4274 
4275 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4276 					 struct inet6_ifaddr *ifa)
4277 {
4278 	struct if6_iter_state *state = seq->private;
4279 	struct net *net = seq_file_net(seq);
4280 
4281 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4282 		if (!net_eq(dev_net(ifa->idev->dev), net))
4283 			continue;
4284 		state->offset++;
4285 		return ifa;
4286 	}
4287 
4288 	state->offset = 0;
4289 	while (++state->bucket < IN6_ADDR_HSIZE) {
4290 		hlist_for_each_entry_rcu(ifa,
4291 				     &inet6_addr_lst[state->bucket], addr_lst) {
4292 			if (!net_eq(dev_net(ifa->idev->dev), net))
4293 				continue;
4294 			return ifa;
4295 		}
4296 	}
4297 
4298 	return NULL;
4299 }
4300 
4301 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4302 	__acquires(rcu)
4303 {
4304 	rcu_read_lock();
4305 	return if6_get_first(seq, *pos);
4306 }
4307 
4308 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4309 {
4310 	struct inet6_ifaddr *ifa;
4311 
4312 	ifa = if6_get_next(seq, v);
4313 	++*pos;
4314 	return ifa;
4315 }
4316 
4317 static void if6_seq_stop(struct seq_file *seq, void *v)
4318 	__releases(rcu)
4319 {
4320 	rcu_read_unlock();
4321 }
4322 
4323 static int if6_seq_show(struct seq_file *seq, void *v)
4324 {
4325 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4326 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4327 		   &ifp->addr,
4328 		   ifp->idev->dev->ifindex,
4329 		   ifp->prefix_len,
4330 		   ifp->scope,
4331 		   (u8) ifp->flags,
4332 		   ifp->idev->dev->name);
4333 	return 0;
4334 }
4335 
4336 static const struct seq_operations if6_seq_ops = {
4337 	.start	= if6_seq_start,
4338 	.next	= if6_seq_next,
4339 	.show	= if6_seq_show,
4340 	.stop	= if6_seq_stop,
4341 };
4342 
4343 static int __net_init if6_proc_net_init(struct net *net)
4344 {
4345 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4346 			sizeof(struct if6_iter_state)))
4347 		return -ENOMEM;
4348 	return 0;
4349 }
4350 
4351 static void __net_exit if6_proc_net_exit(struct net *net)
4352 {
4353 	remove_proc_entry("if_inet6", net->proc_net);
4354 }
4355 
4356 static struct pernet_operations if6_proc_net_ops = {
4357 	.init = if6_proc_net_init,
4358 	.exit = if6_proc_net_exit,
4359 };
4360 
4361 int __init if6_proc_init(void)
4362 {
4363 	return register_pernet_subsys(&if6_proc_net_ops);
4364 }
4365 
4366 void if6_proc_exit(void)
4367 {
4368 	unregister_pernet_subsys(&if6_proc_net_ops);
4369 }
4370 #endif	/* CONFIG_PROC_FS */
4371 
4372 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4373 /* Check if address is a home address configured on any interface. */
4374 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4375 {
4376 	unsigned int hash = inet6_addr_hash(net, addr);
4377 	struct inet6_ifaddr *ifp = NULL;
4378 	int ret = 0;
4379 
4380 	rcu_read_lock();
4381 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4382 		if (!net_eq(dev_net(ifp->idev->dev), net))
4383 			continue;
4384 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4385 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4386 			ret = 1;
4387 			break;
4388 		}
4389 	}
4390 	rcu_read_unlock();
4391 	return ret;
4392 }
4393 #endif
4394 
4395 /* RFC6554 has some algorithm to avoid loops in segment routing by
4396  * checking if the segments contains any of a local interface address.
4397  *
4398  * Quote:
4399  *
4400  * To detect loops in the SRH, a router MUST determine if the SRH
4401  * includes multiple addresses assigned to any interface on that router.
4402  * If such addresses appear more than once and are separated by at least
4403  * one address not assigned to that router.
4404  */
4405 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4406 			  unsigned char nsegs)
4407 {
4408 	const struct in6_addr *addr;
4409 	int i, ret = 0, found = 0;
4410 	struct inet6_ifaddr *ifp;
4411 	bool separated = false;
4412 	unsigned int hash;
4413 	bool hash_found;
4414 
4415 	rcu_read_lock();
4416 	for (i = 0; i < nsegs; i++) {
4417 		addr = &segs[i];
4418 		hash = inet6_addr_hash(net, addr);
4419 
4420 		hash_found = false;
4421 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4422 			if (!net_eq(dev_net(ifp->idev->dev), net))
4423 				continue;
4424 
4425 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4426 				hash_found = true;
4427 				break;
4428 			}
4429 		}
4430 
4431 		if (hash_found) {
4432 			if (found > 1 && separated) {
4433 				ret = 1;
4434 				break;
4435 			}
4436 
4437 			separated = false;
4438 			found++;
4439 		} else {
4440 			separated = true;
4441 		}
4442 	}
4443 	rcu_read_unlock();
4444 
4445 	return ret;
4446 }
4447 
4448 /*
4449  *	Periodic address status verification
4450  */
4451 
4452 static void addrconf_verify_rtnl(void)
4453 {
4454 	unsigned long now, next, next_sec, next_sched;
4455 	struct inet6_ifaddr *ifp;
4456 	int i;
4457 
4458 	ASSERT_RTNL();
4459 
4460 	rcu_read_lock_bh();
4461 	now = jiffies;
4462 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4463 
4464 	cancel_delayed_work(&addr_chk_work);
4465 
4466 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4467 restart:
4468 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4469 			unsigned long age;
4470 
4471 			/* When setting preferred_lft to a value not zero or
4472 			 * infinity, while valid_lft is infinity
4473 			 * IFA_F_PERMANENT has a non-infinity life time.
4474 			 */
4475 			if ((ifp->flags & IFA_F_PERMANENT) &&
4476 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4477 				continue;
4478 
4479 			spin_lock(&ifp->lock);
4480 			/* We try to batch several events at once. */
4481 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4482 
4483 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4484 			    age >= ifp->valid_lft) {
4485 				spin_unlock(&ifp->lock);
4486 				in6_ifa_hold(ifp);
4487 				ipv6_del_addr(ifp);
4488 				goto restart;
4489 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4490 				spin_unlock(&ifp->lock);
4491 				continue;
4492 			} else if (age >= ifp->prefered_lft) {
4493 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4494 				int deprecate = 0;
4495 
4496 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4497 					deprecate = 1;
4498 					ifp->flags |= IFA_F_DEPRECATED;
4499 				}
4500 
4501 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4502 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4503 					next = ifp->tstamp + ifp->valid_lft * HZ;
4504 
4505 				spin_unlock(&ifp->lock);
4506 
4507 				if (deprecate) {
4508 					in6_ifa_hold(ifp);
4509 
4510 					ipv6_ifa_notify(0, ifp);
4511 					in6_ifa_put(ifp);
4512 					goto restart;
4513 				}
4514 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4515 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4516 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4517 					ifp->idev->cnf.dad_transmits *
4518 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4519 
4520 				if (age >= ifp->prefered_lft - regen_advance) {
4521 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4522 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4523 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4524 					if (!ifp->regen_count && ifpub) {
4525 						ifp->regen_count++;
4526 						in6_ifa_hold(ifp);
4527 						in6_ifa_hold(ifpub);
4528 						spin_unlock(&ifp->lock);
4529 
4530 						spin_lock(&ifpub->lock);
4531 						ifpub->regen_count = 0;
4532 						spin_unlock(&ifpub->lock);
4533 						rcu_read_unlock_bh();
4534 						ipv6_create_tempaddr(ifpub, ifp, true);
4535 						in6_ifa_put(ifpub);
4536 						in6_ifa_put(ifp);
4537 						rcu_read_lock_bh();
4538 						goto restart;
4539 					}
4540 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4541 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4542 				spin_unlock(&ifp->lock);
4543 			} else {
4544 				/* ifp->prefered_lft <= ifp->valid_lft */
4545 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4546 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4547 				spin_unlock(&ifp->lock);
4548 			}
4549 		}
4550 	}
4551 
4552 	next_sec = round_jiffies_up(next);
4553 	next_sched = next;
4554 
4555 	/* If rounded timeout is accurate enough, accept it. */
4556 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4557 		next_sched = next_sec;
4558 
4559 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4560 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4561 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4562 
4563 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4564 		 now, next, next_sec, next_sched);
4565 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4566 	rcu_read_unlock_bh();
4567 }
4568 
4569 static void addrconf_verify_work(struct work_struct *w)
4570 {
4571 	rtnl_lock();
4572 	addrconf_verify_rtnl();
4573 	rtnl_unlock();
4574 }
4575 
4576 static void addrconf_verify(void)
4577 {
4578 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4579 }
4580 
4581 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4582 				     struct in6_addr **peer_pfx)
4583 {
4584 	struct in6_addr *pfx = NULL;
4585 
4586 	*peer_pfx = NULL;
4587 
4588 	if (addr)
4589 		pfx = nla_data(addr);
4590 
4591 	if (local) {
4592 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4593 			*peer_pfx = pfx;
4594 		pfx = nla_data(local);
4595 	}
4596 
4597 	return pfx;
4598 }
4599 
4600 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4601 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4602 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4603 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4604 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4605 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4606 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4607 };
4608 
4609 static int
4610 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4611 		  struct netlink_ext_ack *extack)
4612 {
4613 	struct net *net = sock_net(skb->sk);
4614 	struct ifaddrmsg *ifm;
4615 	struct nlattr *tb[IFA_MAX+1];
4616 	struct in6_addr *pfx, *peer_pfx;
4617 	u32 ifa_flags;
4618 	int err;
4619 
4620 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4621 				     ifa_ipv6_policy, extack);
4622 	if (err < 0)
4623 		return err;
4624 
4625 	ifm = nlmsg_data(nlh);
4626 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4627 	if (!pfx)
4628 		return -EINVAL;
4629 
4630 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4631 
4632 	/* We ignore other flags so far. */
4633 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4634 
4635 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4636 			      ifm->ifa_prefixlen);
4637 }
4638 
4639 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4640 			       unsigned long expires, u32 flags,
4641 			       bool modify_peer)
4642 {
4643 	struct fib6_info *f6i;
4644 	u32 prio;
4645 
4646 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4647 					ifp->prefix_len,
4648 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4649 	if (!f6i)
4650 		return -ENOENT;
4651 
4652 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4653 	if (f6i->fib6_metric != prio) {
4654 		/* delete old one */
4655 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4656 
4657 		/* add new one */
4658 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4659 				      ifp->prefix_len,
4660 				      ifp->rt_priority, ifp->idev->dev,
4661 				      expires, flags, GFP_KERNEL);
4662 	} else {
4663 		if (!expires)
4664 			fib6_clean_expires(f6i);
4665 		else
4666 			fib6_set_expires(f6i, expires);
4667 
4668 		fib6_info_release(f6i);
4669 	}
4670 
4671 	return 0;
4672 }
4673 
4674 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4675 {
4676 	u32 flags;
4677 	clock_t expires;
4678 	unsigned long timeout;
4679 	bool was_managetempaddr;
4680 	bool had_prefixroute;
4681 	bool new_peer = false;
4682 
4683 	ASSERT_RTNL();
4684 
4685 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4686 		return -EINVAL;
4687 
4688 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4689 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4690 		return -EINVAL;
4691 
4692 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4693 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4694 
4695 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4696 	if (addrconf_finite_timeout(timeout)) {
4697 		expires = jiffies_to_clock_t(timeout * HZ);
4698 		cfg->valid_lft = timeout;
4699 		flags = RTF_EXPIRES;
4700 	} else {
4701 		expires = 0;
4702 		flags = 0;
4703 		cfg->ifa_flags |= IFA_F_PERMANENT;
4704 	}
4705 
4706 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4707 	if (addrconf_finite_timeout(timeout)) {
4708 		if (timeout == 0)
4709 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4710 		cfg->preferred_lft = timeout;
4711 	}
4712 
4713 	if (cfg->peer_pfx &&
4714 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4715 		if (!ipv6_addr_any(&ifp->peer_addr))
4716 			cleanup_prefix_route(ifp, expires, true, true);
4717 		new_peer = true;
4718 	}
4719 
4720 	spin_lock_bh(&ifp->lock);
4721 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4722 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4723 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4724 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4725 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4726 			IFA_F_NOPREFIXROUTE);
4727 	ifp->flags |= cfg->ifa_flags;
4728 	ifp->tstamp = jiffies;
4729 	ifp->valid_lft = cfg->valid_lft;
4730 	ifp->prefered_lft = cfg->preferred_lft;
4731 
4732 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4733 		ifp->rt_priority = cfg->rt_priority;
4734 
4735 	if (new_peer)
4736 		ifp->peer_addr = *cfg->peer_pfx;
4737 
4738 	spin_unlock_bh(&ifp->lock);
4739 	if (!(ifp->flags&IFA_F_TENTATIVE))
4740 		ipv6_ifa_notify(0, ifp);
4741 
4742 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4743 		int rc = -ENOENT;
4744 
4745 		if (had_prefixroute)
4746 			rc = modify_prefix_route(ifp, expires, flags, false);
4747 
4748 		/* prefix route could have been deleted; if so restore it */
4749 		if (rc == -ENOENT) {
4750 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4751 					      ifp->rt_priority, ifp->idev->dev,
4752 					      expires, flags, GFP_KERNEL);
4753 		}
4754 
4755 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4756 			rc = modify_prefix_route(ifp, expires, flags, true);
4757 
4758 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4759 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4760 					      ifp->rt_priority, ifp->idev->dev,
4761 					      expires, flags, GFP_KERNEL);
4762 		}
4763 	} else if (had_prefixroute) {
4764 		enum cleanup_prefix_rt_t action;
4765 		unsigned long rt_expires;
4766 
4767 		write_lock_bh(&ifp->idev->lock);
4768 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4769 		write_unlock_bh(&ifp->idev->lock);
4770 
4771 		if (action != CLEANUP_PREFIX_RT_NOP) {
4772 			cleanup_prefix_route(ifp, rt_expires,
4773 				action == CLEANUP_PREFIX_RT_DEL, false);
4774 		}
4775 	}
4776 
4777 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4778 		if (was_managetempaddr &&
4779 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4780 			cfg->valid_lft = 0;
4781 			cfg->preferred_lft = 0;
4782 		}
4783 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4784 				 cfg->preferred_lft, !was_managetempaddr,
4785 				 jiffies);
4786 	}
4787 
4788 	addrconf_verify_rtnl();
4789 
4790 	return 0;
4791 }
4792 
4793 static int
4794 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4795 		  struct netlink_ext_ack *extack)
4796 {
4797 	struct net *net = sock_net(skb->sk);
4798 	struct ifaddrmsg *ifm;
4799 	struct nlattr *tb[IFA_MAX+1];
4800 	struct in6_addr *peer_pfx;
4801 	struct inet6_ifaddr *ifa;
4802 	struct net_device *dev;
4803 	struct inet6_dev *idev;
4804 	struct ifa6_config cfg;
4805 	int err;
4806 
4807 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4808 				     ifa_ipv6_policy, extack);
4809 	if (err < 0)
4810 		return err;
4811 
4812 	memset(&cfg, 0, sizeof(cfg));
4813 
4814 	ifm = nlmsg_data(nlh);
4815 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4816 	if (!cfg.pfx)
4817 		return -EINVAL;
4818 
4819 	cfg.peer_pfx = peer_pfx;
4820 	cfg.plen = ifm->ifa_prefixlen;
4821 	if (tb[IFA_RT_PRIORITY])
4822 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4823 
4824 	cfg.valid_lft = INFINITY_LIFE_TIME;
4825 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4826 
4827 	if (tb[IFA_CACHEINFO]) {
4828 		struct ifa_cacheinfo *ci;
4829 
4830 		ci = nla_data(tb[IFA_CACHEINFO]);
4831 		cfg.valid_lft = ci->ifa_valid;
4832 		cfg.preferred_lft = ci->ifa_prefered;
4833 	}
4834 
4835 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4836 	if (!dev)
4837 		return -ENODEV;
4838 
4839 	if (tb[IFA_FLAGS])
4840 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4841 	else
4842 		cfg.ifa_flags = ifm->ifa_flags;
4843 
4844 	/* We ignore other flags so far. */
4845 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4846 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4847 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4848 
4849 	idev = ipv6_find_idev(dev);
4850 	if (IS_ERR(idev))
4851 		return PTR_ERR(idev);
4852 
4853 	if (!ipv6_allow_optimistic_dad(net, idev))
4854 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4855 
4856 	if (cfg.ifa_flags & IFA_F_NODAD &&
4857 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4858 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4859 		return -EINVAL;
4860 	}
4861 
4862 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4863 	if (!ifa) {
4864 		/*
4865 		 * It would be best to check for !NLM_F_CREATE here but
4866 		 * userspace already relies on not having to provide this.
4867 		 */
4868 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4869 	}
4870 
4871 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4872 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4873 		err = -EEXIST;
4874 	else
4875 		err = inet6_addr_modify(ifa, &cfg);
4876 
4877 	in6_ifa_put(ifa);
4878 
4879 	return err;
4880 }
4881 
4882 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4883 			  u8 scope, int ifindex)
4884 {
4885 	struct ifaddrmsg *ifm;
4886 
4887 	ifm = nlmsg_data(nlh);
4888 	ifm->ifa_family = AF_INET6;
4889 	ifm->ifa_prefixlen = prefixlen;
4890 	ifm->ifa_flags = flags;
4891 	ifm->ifa_scope = scope;
4892 	ifm->ifa_index = ifindex;
4893 }
4894 
4895 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4896 			 unsigned long tstamp, u32 preferred, u32 valid)
4897 {
4898 	struct ifa_cacheinfo ci;
4899 
4900 	ci.cstamp = cstamp_delta(cstamp);
4901 	ci.tstamp = cstamp_delta(tstamp);
4902 	ci.ifa_prefered = preferred;
4903 	ci.ifa_valid = valid;
4904 
4905 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4906 }
4907 
4908 static inline int rt_scope(int ifa_scope)
4909 {
4910 	if (ifa_scope & IFA_HOST)
4911 		return RT_SCOPE_HOST;
4912 	else if (ifa_scope & IFA_LINK)
4913 		return RT_SCOPE_LINK;
4914 	else if (ifa_scope & IFA_SITE)
4915 		return RT_SCOPE_SITE;
4916 	else
4917 		return RT_SCOPE_UNIVERSE;
4918 }
4919 
4920 static inline int inet6_ifaddr_msgsize(void)
4921 {
4922 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4923 	       + nla_total_size(16) /* IFA_LOCAL */
4924 	       + nla_total_size(16) /* IFA_ADDRESS */
4925 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4926 	       + nla_total_size(4)  /* IFA_FLAGS */
4927 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4928 }
4929 
4930 enum addr_type_t {
4931 	UNICAST_ADDR,
4932 	MULTICAST_ADDR,
4933 	ANYCAST_ADDR,
4934 };
4935 
4936 struct inet6_fill_args {
4937 	u32 portid;
4938 	u32 seq;
4939 	int event;
4940 	unsigned int flags;
4941 	int netnsid;
4942 	int ifindex;
4943 	enum addr_type_t type;
4944 };
4945 
4946 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4947 			     struct inet6_fill_args *args)
4948 {
4949 	struct nlmsghdr  *nlh;
4950 	u32 preferred, valid;
4951 
4952 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4953 			sizeof(struct ifaddrmsg), args->flags);
4954 	if (!nlh)
4955 		return -EMSGSIZE;
4956 
4957 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4958 		      ifa->idev->dev->ifindex);
4959 
4960 	if (args->netnsid >= 0 &&
4961 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4962 		goto error;
4963 
4964 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4965 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4966 		preferred = ifa->prefered_lft;
4967 		valid = ifa->valid_lft;
4968 		if (preferred != INFINITY_LIFE_TIME) {
4969 			long tval = (jiffies - ifa->tstamp)/HZ;
4970 			if (preferred > tval)
4971 				preferred -= tval;
4972 			else
4973 				preferred = 0;
4974 			if (valid != INFINITY_LIFE_TIME) {
4975 				if (valid > tval)
4976 					valid -= tval;
4977 				else
4978 					valid = 0;
4979 			}
4980 		}
4981 	} else {
4982 		preferred = INFINITY_LIFE_TIME;
4983 		valid = INFINITY_LIFE_TIME;
4984 	}
4985 
4986 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4987 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4988 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4989 			goto error;
4990 	} else
4991 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4992 			goto error;
4993 
4994 	if (ifa->rt_priority &&
4995 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4996 		goto error;
4997 
4998 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4999 		goto error;
5000 
5001 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5002 		goto error;
5003 
5004 	nlmsg_end(skb, nlh);
5005 	return 0;
5006 
5007 error:
5008 	nlmsg_cancel(skb, nlh);
5009 	return -EMSGSIZE;
5010 }
5011 
5012 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5013 			       struct inet6_fill_args *args)
5014 {
5015 	struct nlmsghdr  *nlh;
5016 	u8 scope = RT_SCOPE_UNIVERSE;
5017 	int ifindex = ifmca->idev->dev->ifindex;
5018 
5019 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5020 		scope = RT_SCOPE_SITE;
5021 
5022 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5023 			sizeof(struct ifaddrmsg), args->flags);
5024 	if (!nlh)
5025 		return -EMSGSIZE;
5026 
5027 	if (args->netnsid >= 0 &&
5028 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5029 		return -EMSGSIZE;
5030 
5031 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5032 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5033 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5034 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5035 		nlmsg_cancel(skb, nlh);
5036 		return -EMSGSIZE;
5037 	}
5038 
5039 	nlmsg_end(skb, nlh);
5040 	return 0;
5041 }
5042 
5043 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5044 			       struct inet6_fill_args *args)
5045 {
5046 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5047 	int ifindex = dev ? dev->ifindex : 1;
5048 	struct nlmsghdr  *nlh;
5049 	u8 scope = RT_SCOPE_UNIVERSE;
5050 
5051 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5052 		scope = RT_SCOPE_SITE;
5053 
5054 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5055 			sizeof(struct ifaddrmsg), args->flags);
5056 	if (!nlh)
5057 		return -EMSGSIZE;
5058 
5059 	if (args->netnsid >= 0 &&
5060 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5061 		return -EMSGSIZE;
5062 
5063 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5064 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5065 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5066 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5067 		nlmsg_cancel(skb, nlh);
5068 		return -EMSGSIZE;
5069 	}
5070 
5071 	nlmsg_end(skb, nlh);
5072 	return 0;
5073 }
5074 
5075 /* called with rcu_read_lock() */
5076 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5077 			  struct netlink_callback *cb, int s_ip_idx,
5078 			  struct inet6_fill_args *fillargs)
5079 {
5080 	struct ifmcaddr6 *ifmca;
5081 	struct ifacaddr6 *ifaca;
5082 	int ip_idx = 0;
5083 	int err = 1;
5084 
5085 	read_lock_bh(&idev->lock);
5086 	switch (fillargs->type) {
5087 	case UNICAST_ADDR: {
5088 		struct inet6_ifaddr *ifa;
5089 		fillargs->event = RTM_NEWADDR;
5090 
5091 		/* unicast address incl. temp addr */
5092 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5093 			if (ip_idx < s_ip_idx)
5094 				goto next;
5095 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5096 			if (err < 0)
5097 				break;
5098 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5099 next:
5100 			ip_idx++;
5101 		}
5102 		break;
5103 	}
5104 	case MULTICAST_ADDR:
5105 		fillargs->event = RTM_GETMULTICAST;
5106 
5107 		/* multicast address */
5108 		for (ifmca = idev->mc_list; ifmca;
5109 		     ifmca = ifmca->next, ip_idx++) {
5110 			if (ip_idx < s_ip_idx)
5111 				continue;
5112 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5113 			if (err < 0)
5114 				break;
5115 		}
5116 		break;
5117 	case ANYCAST_ADDR:
5118 		fillargs->event = RTM_GETANYCAST;
5119 		/* anycast address */
5120 		for (ifaca = idev->ac_list; ifaca;
5121 		     ifaca = ifaca->aca_next, ip_idx++) {
5122 			if (ip_idx < s_ip_idx)
5123 				continue;
5124 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5125 			if (err < 0)
5126 				break;
5127 		}
5128 		break;
5129 	default:
5130 		break;
5131 	}
5132 	read_unlock_bh(&idev->lock);
5133 	cb->args[2] = ip_idx;
5134 	return err;
5135 }
5136 
5137 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5138 				       struct inet6_fill_args *fillargs,
5139 				       struct net **tgt_net, struct sock *sk,
5140 				       struct netlink_callback *cb)
5141 {
5142 	struct netlink_ext_ack *extack = cb->extack;
5143 	struct nlattr *tb[IFA_MAX+1];
5144 	struct ifaddrmsg *ifm;
5145 	int err, i;
5146 
5147 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5148 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5149 		return -EINVAL;
5150 	}
5151 
5152 	ifm = nlmsg_data(nlh);
5153 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5154 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5155 		return -EINVAL;
5156 	}
5157 
5158 	fillargs->ifindex = ifm->ifa_index;
5159 	if (fillargs->ifindex) {
5160 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5161 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5162 	}
5163 
5164 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5165 					    ifa_ipv6_policy, extack);
5166 	if (err < 0)
5167 		return err;
5168 
5169 	for (i = 0; i <= IFA_MAX; ++i) {
5170 		if (!tb[i])
5171 			continue;
5172 
5173 		if (i == IFA_TARGET_NETNSID) {
5174 			struct net *net;
5175 
5176 			fillargs->netnsid = nla_get_s32(tb[i]);
5177 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5178 			if (IS_ERR(net)) {
5179 				fillargs->netnsid = -1;
5180 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5181 				return PTR_ERR(net);
5182 			}
5183 			*tgt_net = net;
5184 		} else {
5185 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5186 			return -EINVAL;
5187 		}
5188 	}
5189 
5190 	return 0;
5191 }
5192 
5193 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5194 			   enum addr_type_t type)
5195 {
5196 	const struct nlmsghdr *nlh = cb->nlh;
5197 	struct inet6_fill_args fillargs = {
5198 		.portid = NETLINK_CB(cb->skb).portid,
5199 		.seq = cb->nlh->nlmsg_seq,
5200 		.flags = NLM_F_MULTI,
5201 		.netnsid = -1,
5202 		.type = type,
5203 	};
5204 	struct net *net = sock_net(skb->sk);
5205 	struct net *tgt_net = net;
5206 	int idx, s_idx, s_ip_idx;
5207 	int h, s_h;
5208 	struct net_device *dev;
5209 	struct inet6_dev *idev;
5210 	struct hlist_head *head;
5211 	int err = 0;
5212 
5213 	s_h = cb->args[0];
5214 	s_idx = idx = cb->args[1];
5215 	s_ip_idx = cb->args[2];
5216 
5217 	if (cb->strict_check) {
5218 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5219 						  skb->sk, cb);
5220 		if (err < 0)
5221 			goto put_tgt_net;
5222 
5223 		err = 0;
5224 		if (fillargs.ifindex) {
5225 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5226 			if (!dev) {
5227 				err = -ENODEV;
5228 				goto put_tgt_net;
5229 			}
5230 			idev = __in6_dev_get(dev);
5231 			if (idev) {
5232 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5233 						     &fillargs);
5234 				if (err > 0)
5235 					err = 0;
5236 			}
5237 			goto put_tgt_net;
5238 		}
5239 	}
5240 
5241 	rcu_read_lock();
5242 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5243 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5244 		idx = 0;
5245 		head = &tgt_net->dev_index_head[h];
5246 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5247 			if (idx < s_idx)
5248 				goto cont;
5249 			if (h > s_h || idx > s_idx)
5250 				s_ip_idx = 0;
5251 			idev = __in6_dev_get(dev);
5252 			if (!idev)
5253 				goto cont;
5254 
5255 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5256 					   &fillargs) < 0)
5257 				goto done;
5258 cont:
5259 			idx++;
5260 		}
5261 	}
5262 done:
5263 	rcu_read_unlock();
5264 	cb->args[0] = h;
5265 	cb->args[1] = idx;
5266 put_tgt_net:
5267 	if (fillargs.netnsid >= 0)
5268 		put_net(tgt_net);
5269 
5270 	return skb->len ? : err;
5271 }
5272 
5273 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5274 {
5275 	enum addr_type_t type = UNICAST_ADDR;
5276 
5277 	return inet6_dump_addr(skb, cb, type);
5278 }
5279 
5280 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5281 {
5282 	enum addr_type_t type = MULTICAST_ADDR;
5283 
5284 	return inet6_dump_addr(skb, cb, type);
5285 }
5286 
5287 
5288 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5289 {
5290 	enum addr_type_t type = ANYCAST_ADDR;
5291 
5292 	return inet6_dump_addr(skb, cb, type);
5293 }
5294 
5295 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5296 				       const struct nlmsghdr *nlh,
5297 				       struct nlattr **tb,
5298 				       struct netlink_ext_ack *extack)
5299 {
5300 	struct ifaddrmsg *ifm;
5301 	int i, err;
5302 
5303 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5304 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5305 		return -EINVAL;
5306 	}
5307 
5308 	if (!netlink_strict_get_check(skb))
5309 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5310 					      ifa_ipv6_policy, extack);
5311 
5312 	ifm = nlmsg_data(nlh);
5313 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5314 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5315 		return -EINVAL;
5316 	}
5317 
5318 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5319 					    ifa_ipv6_policy, extack);
5320 	if (err)
5321 		return err;
5322 
5323 	for (i = 0; i <= IFA_MAX; i++) {
5324 		if (!tb[i])
5325 			continue;
5326 
5327 		switch (i) {
5328 		case IFA_TARGET_NETNSID:
5329 		case IFA_ADDRESS:
5330 		case IFA_LOCAL:
5331 			break;
5332 		default:
5333 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5334 			return -EINVAL;
5335 		}
5336 	}
5337 
5338 	return 0;
5339 }
5340 
5341 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5342 			     struct netlink_ext_ack *extack)
5343 {
5344 	struct net *net = sock_net(in_skb->sk);
5345 	struct inet6_fill_args fillargs = {
5346 		.portid = NETLINK_CB(in_skb).portid,
5347 		.seq = nlh->nlmsg_seq,
5348 		.event = RTM_NEWADDR,
5349 		.flags = 0,
5350 		.netnsid = -1,
5351 	};
5352 	struct net *tgt_net = net;
5353 	struct ifaddrmsg *ifm;
5354 	struct nlattr *tb[IFA_MAX+1];
5355 	struct in6_addr *addr = NULL, *peer;
5356 	struct net_device *dev = NULL;
5357 	struct inet6_ifaddr *ifa;
5358 	struct sk_buff *skb;
5359 	int err;
5360 
5361 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5362 	if (err < 0)
5363 		return err;
5364 
5365 	if (tb[IFA_TARGET_NETNSID]) {
5366 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5367 
5368 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5369 						  fillargs.netnsid);
5370 		if (IS_ERR(tgt_net))
5371 			return PTR_ERR(tgt_net);
5372 	}
5373 
5374 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5375 	if (!addr)
5376 		return -EINVAL;
5377 
5378 	ifm = nlmsg_data(nlh);
5379 	if (ifm->ifa_index)
5380 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5381 
5382 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5383 	if (!ifa) {
5384 		err = -EADDRNOTAVAIL;
5385 		goto errout;
5386 	}
5387 
5388 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5389 	if (!skb) {
5390 		err = -ENOBUFS;
5391 		goto errout_ifa;
5392 	}
5393 
5394 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5395 	if (err < 0) {
5396 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5397 		WARN_ON(err == -EMSGSIZE);
5398 		kfree_skb(skb);
5399 		goto errout_ifa;
5400 	}
5401 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5402 errout_ifa:
5403 	in6_ifa_put(ifa);
5404 errout:
5405 	if (dev)
5406 		dev_put(dev);
5407 	if (fillargs.netnsid >= 0)
5408 		put_net(tgt_net);
5409 
5410 	return err;
5411 }
5412 
5413 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5414 {
5415 	struct sk_buff *skb;
5416 	struct net *net = dev_net(ifa->idev->dev);
5417 	struct inet6_fill_args fillargs = {
5418 		.portid = 0,
5419 		.seq = 0,
5420 		.event = event,
5421 		.flags = 0,
5422 		.netnsid = -1,
5423 	};
5424 	int err = -ENOBUFS;
5425 
5426 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5427 	if (!skb)
5428 		goto errout;
5429 
5430 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5431 	if (err < 0) {
5432 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5433 		WARN_ON(err == -EMSGSIZE);
5434 		kfree_skb(skb);
5435 		goto errout;
5436 	}
5437 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5438 	return;
5439 errout:
5440 	if (err < 0)
5441 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5442 }
5443 
5444 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5445 				__s32 *array, int bytes)
5446 {
5447 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5448 
5449 	memset(array, 0, bytes);
5450 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5451 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5452 	array[DEVCONF_MTU6] = cnf->mtu6;
5453 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5454 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5455 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5456 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5457 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5458 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5459 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5460 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5461 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5462 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5463 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5464 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5465 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5466 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5467 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5468 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5469 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5470 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5471 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5472 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5473 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5474 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5475 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5476 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5477 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5478 #ifdef CONFIG_IPV6_ROUTER_PREF
5479 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5480 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5481 		jiffies_to_msecs(cnf->rtr_probe_interval);
5482 #ifdef CONFIG_IPV6_ROUTE_INFO
5483 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5484 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5485 #endif
5486 #endif
5487 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5488 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5489 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5490 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5491 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5492 #endif
5493 #ifdef CONFIG_IPV6_MROUTE
5494 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5495 #endif
5496 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5497 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5498 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5499 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5500 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5501 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5502 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5503 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5504 	/* we omit DEVCONF_STABLE_SECRET for now */
5505 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5506 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5507 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5508 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5509 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5510 #ifdef CONFIG_IPV6_SEG6_HMAC
5511 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5512 #endif
5513 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5514 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5515 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5516 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5517 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5518 }
5519 
5520 static inline size_t inet6_ifla6_size(void)
5521 {
5522 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5523 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5524 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5525 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5526 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5527 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5528 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5529 	     + 0;
5530 }
5531 
5532 static inline size_t inet6_if_nlmsg_size(void)
5533 {
5534 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5535 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5536 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5537 	       + nla_total_size(4) /* IFLA_MTU */
5538 	       + nla_total_size(4) /* IFLA_LINK */
5539 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5540 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5541 }
5542 
5543 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5544 					int bytes)
5545 {
5546 	int i;
5547 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5548 	BUG_ON(pad < 0);
5549 
5550 	/* Use put_unaligned() because stats may not be aligned for u64. */
5551 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5552 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5553 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5554 
5555 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5556 }
5557 
5558 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5559 					int bytes, size_t syncpoff)
5560 {
5561 	int i, c;
5562 	u64 buff[IPSTATS_MIB_MAX];
5563 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5564 
5565 	BUG_ON(pad < 0);
5566 
5567 	memset(buff, 0, sizeof(buff));
5568 	buff[0] = IPSTATS_MIB_MAX;
5569 
5570 	for_each_possible_cpu(c) {
5571 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5572 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5573 	}
5574 
5575 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5576 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5577 }
5578 
5579 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5580 			     int bytes)
5581 {
5582 	switch (attrtype) {
5583 	case IFLA_INET6_STATS:
5584 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5585 				     offsetof(struct ipstats_mib, syncp));
5586 		break;
5587 	case IFLA_INET6_ICMP6STATS:
5588 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5589 		break;
5590 	}
5591 }
5592 
5593 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5594 				  u32 ext_filter_mask)
5595 {
5596 	struct nlattr *nla;
5597 	struct ifla_cacheinfo ci;
5598 
5599 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5600 		goto nla_put_failure;
5601 	ci.max_reasm_len = IPV6_MAXPLEN;
5602 	ci.tstamp = cstamp_delta(idev->tstamp);
5603 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5604 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5605 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5606 		goto nla_put_failure;
5607 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5608 	if (!nla)
5609 		goto nla_put_failure;
5610 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5611 
5612 	/* XXX - MC not implemented */
5613 
5614 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5615 		return 0;
5616 
5617 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5618 	if (!nla)
5619 		goto nla_put_failure;
5620 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5621 
5622 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5623 	if (!nla)
5624 		goto nla_put_failure;
5625 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5626 
5627 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5628 	if (!nla)
5629 		goto nla_put_failure;
5630 	read_lock_bh(&idev->lock);
5631 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5632 	read_unlock_bh(&idev->lock);
5633 
5634 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5635 		goto nla_put_failure;
5636 
5637 	return 0;
5638 
5639 nla_put_failure:
5640 	return -EMSGSIZE;
5641 }
5642 
5643 static size_t inet6_get_link_af_size(const struct net_device *dev,
5644 				     u32 ext_filter_mask)
5645 {
5646 	if (!__in6_dev_get(dev))
5647 		return 0;
5648 
5649 	return inet6_ifla6_size();
5650 }
5651 
5652 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5653 			      u32 ext_filter_mask)
5654 {
5655 	struct inet6_dev *idev = __in6_dev_get(dev);
5656 
5657 	if (!idev)
5658 		return -ENODATA;
5659 
5660 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5661 		return -EMSGSIZE;
5662 
5663 	return 0;
5664 }
5665 
5666 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5667 {
5668 	struct inet6_ifaddr *ifp;
5669 	struct net_device *dev = idev->dev;
5670 	bool clear_token, update_rs = false;
5671 	struct in6_addr ll_addr;
5672 
5673 	ASSERT_RTNL();
5674 
5675 	if (!token)
5676 		return -EINVAL;
5677 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5678 		return -EINVAL;
5679 	if (!ipv6_accept_ra(idev))
5680 		return -EINVAL;
5681 	if (idev->cnf.rtr_solicits == 0)
5682 		return -EINVAL;
5683 
5684 	write_lock_bh(&idev->lock);
5685 
5686 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5687 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5688 
5689 	write_unlock_bh(&idev->lock);
5690 
5691 	clear_token = ipv6_addr_any(token);
5692 	if (clear_token)
5693 		goto update_lft;
5694 
5695 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5696 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5697 			     IFA_F_OPTIMISTIC)) {
5698 		/* If we're not ready, then normal ifup will take care
5699 		 * of this. Otherwise, we need to request our rs here.
5700 		 */
5701 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5702 		update_rs = true;
5703 	}
5704 
5705 update_lft:
5706 	write_lock_bh(&idev->lock);
5707 
5708 	if (update_rs) {
5709 		idev->if_flags |= IF_RS_SENT;
5710 		idev->rs_interval = rfc3315_s14_backoff_init(
5711 			idev->cnf.rtr_solicit_interval);
5712 		idev->rs_probes = 1;
5713 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5714 	}
5715 
5716 	/* Well, that's kinda nasty ... */
5717 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5718 		spin_lock(&ifp->lock);
5719 		if (ifp->tokenized) {
5720 			ifp->valid_lft = 0;
5721 			ifp->prefered_lft = 0;
5722 		}
5723 		spin_unlock(&ifp->lock);
5724 	}
5725 
5726 	write_unlock_bh(&idev->lock);
5727 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5728 	addrconf_verify_rtnl();
5729 	return 0;
5730 }
5731 
5732 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5733 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5734 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5735 };
5736 
5737 static int check_addr_gen_mode(int mode)
5738 {
5739 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5740 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5741 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5742 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5743 		return -EINVAL;
5744 	return 1;
5745 }
5746 
5747 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5748 				int mode)
5749 {
5750 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5751 	    !idev->cnf.stable_secret.initialized &&
5752 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5753 		return -EINVAL;
5754 	return 1;
5755 }
5756 
5757 static int inet6_validate_link_af(const struct net_device *dev,
5758 				  const struct nlattr *nla)
5759 {
5760 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5761 	struct inet6_dev *idev = NULL;
5762 	int err;
5763 
5764 	if (dev) {
5765 		idev = __in6_dev_get(dev);
5766 		if (!idev)
5767 			return -EAFNOSUPPORT;
5768 	}
5769 
5770 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5771 					  inet6_af_policy, NULL);
5772 	if (err)
5773 		return err;
5774 
5775 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5776 		return -EINVAL;
5777 
5778 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5779 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5780 
5781 		if (check_addr_gen_mode(mode) < 0)
5782 			return -EINVAL;
5783 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5784 			return -EINVAL;
5785 	}
5786 
5787 	return 0;
5788 }
5789 
5790 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5791 {
5792 	struct inet6_dev *idev = __in6_dev_get(dev);
5793 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5794 	int err;
5795 
5796 	if (!idev)
5797 		return -EAFNOSUPPORT;
5798 
5799 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5800 		BUG();
5801 
5802 	if (tb[IFLA_INET6_TOKEN]) {
5803 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5804 		if (err)
5805 			return err;
5806 	}
5807 
5808 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5809 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5810 
5811 		idev->cnf.addr_gen_mode = mode;
5812 	}
5813 
5814 	return 0;
5815 }
5816 
5817 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5818 			     u32 portid, u32 seq, int event, unsigned int flags)
5819 {
5820 	struct net_device *dev = idev->dev;
5821 	struct ifinfomsg *hdr;
5822 	struct nlmsghdr *nlh;
5823 	void *protoinfo;
5824 
5825 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5826 	if (!nlh)
5827 		return -EMSGSIZE;
5828 
5829 	hdr = nlmsg_data(nlh);
5830 	hdr->ifi_family = AF_INET6;
5831 	hdr->__ifi_pad = 0;
5832 	hdr->ifi_type = dev->type;
5833 	hdr->ifi_index = dev->ifindex;
5834 	hdr->ifi_flags = dev_get_flags(dev);
5835 	hdr->ifi_change = 0;
5836 
5837 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5838 	    (dev->addr_len &&
5839 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5840 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5841 	    (dev->ifindex != dev_get_iflink(dev) &&
5842 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5843 	    nla_put_u8(skb, IFLA_OPERSTATE,
5844 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5845 		goto nla_put_failure;
5846 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5847 	if (!protoinfo)
5848 		goto nla_put_failure;
5849 
5850 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5851 		goto nla_put_failure;
5852 
5853 	nla_nest_end(skb, protoinfo);
5854 	nlmsg_end(skb, nlh);
5855 	return 0;
5856 
5857 nla_put_failure:
5858 	nlmsg_cancel(skb, nlh);
5859 	return -EMSGSIZE;
5860 }
5861 
5862 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5863 				   struct netlink_ext_ack *extack)
5864 {
5865 	struct ifinfomsg *ifm;
5866 
5867 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5868 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5869 		return -EINVAL;
5870 	}
5871 
5872 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5873 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5874 		return -EINVAL;
5875 	}
5876 
5877 	ifm = nlmsg_data(nlh);
5878 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5879 	    ifm->ifi_change || ifm->ifi_index) {
5880 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5881 		return -EINVAL;
5882 	}
5883 
5884 	return 0;
5885 }
5886 
5887 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5888 {
5889 	struct net *net = sock_net(skb->sk);
5890 	int h, s_h;
5891 	int idx = 0, s_idx;
5892 	struct net_device *dev;
5893 	struct inet6_dev *idev;
5894 	struct hlist_head *head;
5895 
5896 	/* only requests using strict checking can pass data to
5897 	 * influence the dump
5898 	 */
5899 	if (cb->strict_check) {
5900 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5901 
5902 		if (err < 0)
5903 			return err;
5904 	}
5905 
5906 	s_h = cb->args[0];
5907 	s_idx = cb->args[1];
5908 
5909 	rcu_read_lock();
5910 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5911 		idx = 0;
5912 		head = &net->dev_index_head[h];
5913 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5914 			if (idx < s_idx)
5915 				goto cont;
5916 			idev = __in6_dev_get(dev);
5917 			if (!idev)
5918 				goto cont;
5919 			if (inet6_fill_ifinfo(skb, idev,
5920 					      NETLINK_CB(cb->skb).portid,
5921 					      cb->nlh->nlmsg_seq,
5922 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5923 				goto out;
5924 cont:
5925 			idx++;
5926 		}
5927 	}
5928 out:
5929 	rcu_read_unlock();
5930 	cb->args[1] = idx;
5931 	cb->args[0] = h;
5932 
5933 	return skb->len;
5934 }
5935 
5936 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5937 {
5938 	struct sk_buff *skb;
5939 	struct net *net = dev_net(idev->dev);
5940 	int err = -ENOBUFS;
5941 
5942 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5943 	if (!skb)
5944 		goto errout;
5945 
5946 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5947 	if (err < 0) {
5948 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5949 		WARN_ON(err == -EMSGSIZE);
5950 		kfree_skb(skb);
5951 		goto errout;
5952 	}
5953 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5954 	return;
5955 errout:
5956 	if (err < 0)
5957 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5958 }
5959 
5960 static inline size_t inet6_prefix_nlmsg_size(void)
5961 {
5962 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5963 	       + nla_total_size(sizeof(struct in6_addr))
5964 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5965 }
5966 
5967 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5968 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5969 			     int event, unsigned int flags)
5970 {
5971 	struct prefixmsg *pmsg;
5972 	struct nlmsghdr *nlh;
5973 	struct prefix_cacheinfo	ci;
5974 
5975 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5976 	if (!nlh)
5977 		return -EMSGSIZE;
5978 
5979 	pmsg = nlmsg_data(nlh);
5980 	pmsg->prefix_family = AF_INET6;
5981 	pmsg->prefix_pad1 = 0;
5982 	pmsg->prefix_pad2 = 0;
5983 	pmsg->prefix_ifindex = idev->dev->ifindex;
5984 	pmsg->prefix_len = pinfo->prefix_len;
5985 	pmsg->prefix_type = pinfo->type;
5986 	pmsg->prefix_pad3 = 0;
5987 	pmsg->prefix_flags = 0;
5988 	if (pinfo->onlink)
5989 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5990 	if (pinfo->autoconf)
5991 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5992 
5993 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5994 		goto nla_put_failure;
5995 	ci.preferred_time = ntohl(pinfo->prefered);
5996 	ci.valid_time = ntohl(pinfo->valid);
5997 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5998 		goto nla_put_failure;
5999 	nlmsg_end(skb, nlh);
6000 	return 0;
6001 
6002 nla_put_failure:
6003 	nlmsg_cancel(skb, nlh);
6004 	return -EMSGSIZE;
6005 }
6006 
6007 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6008 			 struct prefix_info *pinfo)
6009 {
6010 	struct sk_buff *skb;
6011 	struct net *net = dev_net(idev->dev);
6012 	int err = -ENOBUFS;
6013 
6014 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6015 	if (!skb)
6016 		goto errout;
6017 
6018 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6019 	if (err < 0) {
6020 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6021 		WARN_ON(err == -EMSGSIZE);
6022 		kfree_skb(skb);
6023 		goto errout;
6024 	}
6025 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6026 	return;
6027 errout:
6028 	if (err < 0)
6029 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6030 }
6031 
6032 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6033 {
6034 	struct net *net = dev_net(ifp->idev->dev);
6035 
6036 	if (event)
6037 		ASSERT_RTNL();
6038 
6039 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6040 
6041 	switch (event) {
6042 	case RTM_NEWADDR:
6043 		/*
6044 		 * If the address was optimistic we inserted the route at the
6045 		 * start of our DAD process, so we don't need to do it again.
6046 		 * If the device was taken down in the middle of the DAD
6047 		 * cycle there is a race where we could get here without a
6048 		 * host route, so nothing to insert. That will be fixed when
6049 		 * the device is brought up.
6050 		 */
6051 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6052 			ip6_ins_rt(net, ifp->rt);
6053 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6054 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6055 				&ifp->addr, ifp->idev->dev->name);
6056 		}
6057 
6058 		if (ifp->idev->cnf.forwarding)
6059 			addrconf_join_anycast(ifp);
6060 		if (!ipv6_addr_any(&ifp->peer_addr))
6061 			addrconf_prefix_route(&ifp->peer_addr, 128,
6062 					      ifp->rt_priority, ifp->idev->dev,
6063 					      0, 0, GFP_ATOMIC);
6064 		break;
6065 	case RTM_DELADDR:
6066 		if (ifp->idev->cnf.forwarding)
6067 			addrconf_leave_anycast(ifp);
6068 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6069 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6070 			struct fib6_info *rt;
6071 
6072 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6073 						       ifp->idev->dev, 0, 0,
6074 						       false);
6075 			if (rt)
6076 				ip6_del_rt(net, rt, false);
6077 		}
6078 		if (ifp->rt) {
6079 			ip6_del_rt(net, ifp->rt, false);
6080 			ifp->rt = NULL;
6081 		}
6082 		rt_genid_bump_ipv6(net);
6083 		break;
6084 	}
6085 	atomic_inc(&net->ipv6.dev_addr_genid);
6086 }
6087 
6088 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6089 {
6090 	rcu_read_lock_bh();
6091 	if (likely(ifp->idev->dead == 0))
6092 		__ipv6_ifa_notify(event, ifp);
6093 	rcu_read_unlock_bh();
6094 }
6095 
6096 #ifdef CONFIG_SYSCTL
6097 
6098 static
6099 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6100 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6101 {
6102 	int *valp = ctl->data;
6103 	int val = *valp;
6104 	loff_t pos = *ppos;
6105 	struct ctl_table lctl;
6106 	int ret;
6107 
6108 	/*
6109 	 * ctl->data points to idev->cnf.forwarding, we should
6110 	 * not modify it until we get the rtnl lock.
6111 	 */
6112 	lctl = *ctl;
6113 	lctl.data = &val;
6114 
6115 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6116 
6117 	if (write)
6118 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6119 	if (ret)
6120 		*ppos = pos;
6121 	return ret;
6122 }
6123 
6124 static
6125 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6126 			void __user *buffer, size_t *lenp, loff_t *ppos)
6127 {
6128 	struct inet6_dev *idev = ctl->extra1;
6129 	int min_mtu = IPV6_MIN_MTU;
6130 	struct ctl_table lctl;
6131 
6132 	lctl = *ctl;
6133 	lctl.extra1 = &min_mtu;
6134 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6135 
6136 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6137 }
6138 
6139 static void dev_disable_change(struct inet6_dev *idev)
6140 {
6141 	struct netdev_notifier_info info;
6142 
6143 	if (!idev || !idev->dev)
6144 		return;
6145 
6146 	netdev_notifier_info_init(&info, idev->dev);
6147 	if (idev->cnf.disable_ipv6)
6148 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6149 	else
6150 		addrconf_notify(NULL, NETDEV_UP, &info);
6151 }
6152 
6153 static void addrconf_disable_change(struct net *net, __s32 newf)
6154 {
6155 	struct net_device *dev;
6156 	struct inet6_dev *idev;
6157 
6158 	for_each_netdev(net, dev) {
6159 		idev = __in6_dev_get(dev);
6160 		if (idev) {
6161 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6162 			idev->cnf.disable_ipv6 = newf;
6163 			if (changed)
6164 				dev_disable_change(idev);
6165 		}
6166 	}
6167 }
6168 
6169 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6170 {
6171 	struct net *net;
6172 	int old;
6173 
6174 	if (!rtnl_trylock())
6175 		return restart_syscall();
6176 
6177 	net = (struct net *)table->extra2;
6178 	old = *p;
6179 	*p = newf;
6180 
6181 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6182 		rtnl_unlock();
6183 		return 0;
6184 	}
6185 
6186 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6187 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6188 		addrconf_disable_change(net, newf);
6189 	} else if ((!newf) ^ (!old))
6190 		dev_disable_change((struct inet6_dev *)table->extra1);
6191 
6192 	rtnl_unlock();
6193 	return 0;
6194 }
6195 
6196 static
6197 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6198 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6199 {
6200 	int *valp = ctl->data;
6201 	int val = *valp;
6202 	loff_t pos = *ppos;
6203 	struct ctl_table lctl;
6204 	int ret;
6205 
6206 	/*
6207 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6208 	 * not modify it until we get the rtnl lock.
6209 	 */
6210 	lctl = *ctl;
6211 	lctl.data = &val;
6212 
6213 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6214 
6215 	if (write)
6216 		ret = addrconf_disable_ipv6(ctl, valp, val);
6217 	if (ret)
6218 		*ppos = pos;
6219 	return ret;
6220 }
6221 
6222 static
6223 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6224 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6225 {
6226 	int *valp = ctl->data;
6227 	int ret;
6228 	int old, new;
6229 
6230 	old = *valp;
6231 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6232 	new = *valp;
6233 
6234 	if (write && old != new) {
6235 		struct net *net = ctl->extra2;
6236 
6237 		if (!rtnl_trylock())
6238 			return restart_syscall();
6239 
6240 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6241 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6242 						     NETCONFA_PROXY_NEIGH,
6243 						     NETCONFA_IFINDEX_DEFAULT,
6244 						     net->ipv6.devconf_dflt);
6245 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6246 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6247 						     NETCONFA_PROXY_NEIGH,
6248 						     NETCONFA_IFINDEX_ALL,
6249 						     net->ipv6.devconf_all);
6250 		else {
6251 			struct inet6_dev *idev = ctl->extra1;
6252 
6253 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6254 						     NETCONFA_PROXY_NEIGH,
6255 						     idev->dev->ifindex,
6256 						     &idev->cnf);
6257 		}
6258 		rtnl_unlock();
6259 	}
6260 
6261 	return ret;
6262 }
6263 
6264 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6265 					 void __user *buffer, size_t *lenp,
6266 					 loff_t *ppos)
6267 {
6268 	int ret = 0;
6269 	u32 new_val;
6270 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6271 	struct net *net = (struct net *)ctl->extra2;
6272 	struct ctl_table tmp = {
6273 		.data = &new_val,
6274 		.maxlen = sizeof(new_val),
6275 		.mode = ctl->mode,
6276 	};
6277 
6278 	if (!rtnl_trylock())
6279 		return restart_syscall();
6280 
6281 	new_val = *((u32 *)ctl->data);
6282 
6283 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6284 	if (ret != 0)
6285 		goto out;
6286 
6287 	if (write) {
6288 		if (check_addr_gen_mode(new_val) < 0) {
6289 			ret = -EINVAL;
6290 			goto out;
6291 		}
6292 
6293 		if (idev) {
6294 			if (check_stable_privacy(idev, net, new_val) < 0) {
6295 				ret = -EINVAL;
6296 				goto out;
6297 			}
6298 
6299 			if (idev->cnf.addr_gen_mode != new_val) {
6300 				idev->cnf.addr_gen_mode = new_val;
6301 				addrconf_dev_config(idev->dev);
6302 			}
6303 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6304 			struct net_device *dev;
6305 
6306 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6307 			for_each_netdev(net, dev) {
6308 				idev = __in6_dev_get(dev);
6309 				if (idev &&
6310 				    idev->cnf.addr_gen_mode != new_val) {
6311 					idev->cnf.addr_gen_mode = new_val;
6312 					addrconf_dev_config(idev->dev);
6313 				}
6314 			}
6315 		}
6316 
6317 		*((u32 *)ctl->data) = new_val;
6318 	}
6319 
6320 out:
6321 	rtnl_unlock();
6322 
6323 	return ret;
6324 }
6325 
6326 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6327 					 void __user *buffer, size_t *lenp,
6328 					 loff_t *ppos)
6329 {
6330 	int err;
6331 	struct in6_addr addr;
6332 	char str[IPV6_MAX_STRLEN];
6333 	struct ctl_table lctl = *ctl;
6334 	struct net *net = ctl->extra2;
6335 	struct ipv6_stable_secret *secret = ctl->data;
6336 
6337 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6338 		return -EIO;
6339 
6340 	lctl.maxlen = IPV6_MAX_STRLEN;
6341 	lctl.data = str;
6342 
6343 	if (!rtnl_trylock())
6344 		return restart_syscall();
6345 
6346 	if (!write && !secret->initialized) {
6347 		err = -EIO;
6348 		goto out;
6349 	}
6350 
6351 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6352 	if (err >= sizeof(str)) {
6353 		err = -EIO;
6354 		goto out;
6355 	}
6356 
6357 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6358 	if (err || !write)
6359 		goto out;
6360 
6361 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6362 		err = -EIO;
6363 		goto out;
6364 	}
6365 
6366 	secret->initialized = true;
6367 	secret->secret = addr;
6368 
6369 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6370 		struct net_device *dev;
6371 
6372 		for_each_netdev(net, dev) {
6373 			struct inet6_dev *idev = __in6_dev_get(dev);
6374 
6375 			if (idev) {
6376 				idev->cnf.addr_gen_mode =
6377 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6378 			}
6379 		}
6380 	} else {
6381 		struct inet6_dev *idev = ctl->extra1;
6382 
6383 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6384 	}
6385 
6386 out:
6387 	rtnl_unlock();
6388 
6389 	return err;
6390 }
6391 
6392 static
6393 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6394 						int write,
6395 						void __user *buffer,
6396 						size_t *lenp,
6397 						loff_t *ppos)
6398 {
6399 	int *valp = ctl->data;
6400 	int val = *valp;
6401 	loff_t pos = *ppos;
6402 	struct ctl_table lctl;
6403 	int ret;
6404 
6405 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6406 	 * we should not modify it until we get the rtnl lock.
6407 	 */
6408 	lctl = *ctl;
6409 	lctl.data = &val;
6410 
6411 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6412 
6413 	if (write)
6414 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6415 	if (ret)
6416 		*ppos = pos;
6417 	return ret;
6418 }
6419 
6420 static
6421 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6422 {
6423 	if (rt) {
6424 		if (action)
6425 			rt->dst.flags |= DST_NOPOLICY;
6426 		else
6427 			rt->dst.flags &= ~DST_NOPOLICY;
6428 	}
6429 }
6430 
6431 static
6432 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6433 {
6434 	struct inet6_ifaddr *ifa;
6435 
6436 	read_lock_bh(&idev->lock);
6437 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6438 		spin_lock(&ifa->lock);
6439 		if (ifa->rt) {
6440 			/* host routes only use builtin fib6_nh */
6441 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6442 			int cpu;
6443 
6444 			rcu_read_lock();
6445 			ifa->rt->dst_nopolicy = val ? true : false;
6446 			if (nh->rt6i_pcpu) {
6447 				for_each_possible_cpu(cpu) {
6448 					struct rt6_info **rtp;
6449 
6450 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6451 					addrconf_set_nopolicy(*rtp, val);
6452 				}
6453 			}
6454 			rcu_read_unlock();
6455 		}
6456 		spin_unlock(&ifa->lock);
6457 	}
6458 	read_unlock_bh(&idev->lock);
6459 }
6460 
6461 static
6462 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6463 {
6464 	struct inet6_dev *idev;
6465 	struct net *net;
6466 
6467 	if (!rtnl_trylock())
6468 		return restart_syscall();
6469 
6470 	*valp = val;
6471 
6472 	net = (struct net *)ctl->extra2;
6473 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6474 		rtnl_unlock();
6475 		return 0;
6476 	}
6477 
6478 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6479 		struct net_device *dev;
6480 
6481 		for_each_netdev(net, dev) {
6482 			idev = __in6_dev_get(dev);
6483 			if (idev)
6484 				addrconf_disable_policy_idev(idev, val);
6485 		}
6486 	} else {
6487 		idev = (struct inet6_dev *)ctl->extra1;
6488 		addrconf_disable_policy_idev(idev, val);
6489 	}
6490 
6491 	rtnl_unlock();
6492 	return 0;
6493 }
6494 
6495 static
6496 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6497 				   void __user *buffer, size_t *lenp,
6498 				   loff_t *ppos)
6499 {
6500 	int *valp = ctl->data;
6501 	int val = *valp;
6502 	loff_t pos = *ppos;
6503 	struct ctl_table lctl;
6504 	int ret;
6505 
6506 	lctl = *ctl;
6507 	lctl.data = &val;
6508 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6509 
6510 	if (write && (*valp != val))
6511 		ret = addrconf_disable_policy(ctl, valp, val);
6512 
6513 	if (ret)
6514 		*ppos = pos;
6515 
6516 	return ret;
6517 }
6518 
6519 static int minus_one = -1;
6520 static const int two_five_five = 255;
6521 
6522 static const struct ctl_table addrconf_sysctl[] = {
6523 	{
6524 		.procname	= "forwarding",
6525 		.data		= &ipv6_devconf.forwarding,
6526 		.maxlen		= sizeof(int),
6527 		.mode		= 0644,
6528 		.proc_handler	= addrconf_sysctl_forward,
6529 	},
6530 	{
6531 		.procname	= "hop_limit",
6532 		.data		= &ipv6_devconf.hop_limit,
6533 		.maxlen		= sizeof(int),
6534 		.mode		= 0644,
6535 		.proc_handler	= proc_dointvec_minmax,
6536 		.extra1		= (void *)SYSCTL_ONE,
6537 		.extra2		= (void *)&two_five_five,
6538 	},
6539 	{
6540 		.procname	= "mtu",
6541 		.data		= &ipv6_devconf.mtu6,
6542 		.maxlen		= sizeof(int),
6543 		.mode		= 0644,
6544 		.proc_handler	= addrconf_sysctl_mtu,
6545 	},
6546 	{
6547 		.procname	= "accept_ra",
6548 		.data		= &ipv6_devconf.accept_ra,
6549 		.maxlen		= sizeof(int),
6550 		.mode		= 0644,
6551 		.proc_handler	= proc_dointvec,
6552 	},
6553 	{
6554 		.procname	= "accept_redirects",
6555 		.data		= &ipv6_devconf.accept_redirects,
6556 		.maxlen		= sizeof(int),
6557 		.mode		= 0644,
6558 		.proc_handler	= proc_dointvec,
6559 	},
6560 	{
6561 		.procname	= "autoconf",
6562 		.data		= &ipv6_devconf.autoconf,
6563 		.maxlen		= sizeof(int),
6564 		.mode		= 0644,
6565 		.proc_handler	= proc_dointvec,
6566 	},
6567 	{
6568 		.procname	= "dad_transmits",
6569 		.data		= &ipv6_devconf.dad_transmits,
6570 		.maxlen		= sizeof(int),
6571 		.mode		= 0644,
6572 		.proc_handler	= proc_dointvec,
6573 	},
6574 	{
6575 		.procname	= "router_solicitations",
6576 		.data		= &ipv6_devconf.rtr_solicits,
6577 		.maxlen		= sizeof(int),
6578 		.mode		= 0644,
6579 		.proc_handler	= proc_dointvec_minmax,
6580 		.extra1		= &minus_one,
6581 	},
6582 	{
6583 		.procname	= "router_solicitation_interval",
6584 		.data		= &ipv6_devconf.rtr_solicit_interval,
6585 		.maxlen		= sizeof(int),
6586 		.mode		= 0644,
6587 		.proc_handler	= proc_dointvec_jiffies,
6588 	},
6589 	{
6590 		.procname	= "router_solicitation_max_interval",
6591 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6592 		.maxlen		= sizeof(int),
6593 		.mode		= 0644,
6594 		.proc_handler	= proc_dointvec_jiffies,
6595 	},
6596 	{
6597 		.procname	= "router_solicitation_delay",
6598 		.data		= &ipv6_devconf.rtr_solicit_delay,
6599 		.maxlen		= sizeof(int),
6600 		.mode		= 0644,
6601 		.proc_handler	= proc_dointvec_jiffies,
6602 	},
6603 	{
6604 		.procname	= "force_mld_version",
6605 		.data		= &ipv6_devconf.force_mld_version,
6606 		.maxlen		= sizeof(int),
6607 		.mode		= 0644,
6608 		.proc_handler	= proc_dointvec,
6609 	},
6610 	{
6611 		.procname	= "mldv1_unsolicited_report_interval",
6612 		.data		=
6613 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6614 		.maxlen		= sizeof(int),
6615 		.mode		= 0644,
6616 		.proc_handler	= proc_dointvec_ms_jiffies,
6617 	},
6618 	{
6619 		.procname	= "mldv2_unsolicited_report_interval",
6620 		.data		=
6621 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6622 		.maxlen		= sizeof(int),
6623 		.mode		= 0644,
6624 		.proc_handler	= proc_dointvec_ms_jiffies,
6625 	},
6626 	{
6627 		.procname	= "use_tempaddr",
6628 		.data		= &ipv6_devconf.use_tempaddr,
6629 		.maxlen		= sizeof(int),
6630 		.mode		= 0644,
6631 		.proc_handler	= proc_dointvec,
6632 	},
6633 	{
6634 		.procname	= "temp_valid_lft",
6635 		.data		= &ipv6_devconf.temp_valid_lft,
6636 		.maxlen		= sizeof(int),
6637 		.mode		= 0644,
6638 		.proc_handler	= proc_dointvec,
6639 	},
6640 	{
6641 		.procname	= "temp_prefered_lft",
6642 		.data		= &ipv6_devconf.temp_prefered_lft,
6643 		.maxlen		= sizeof(int),
6644 		.mode		= 0644,
6645 		.proc_handler	= proc_dointvec,
6646 	},
6647 	{
6648 		.procname	= "regen_max_retry",
6649 		.data		= &ipv6_devconf.regen_max_retry,
6650 		.maxlen		= sizeof(int),
6651 		.mode		= 0644,
6652 		.proc_handler	= proc_dointvec,
6653 	},
6654 	{
6655 		.procname	= "max_desync_factor",
6656 		.data		= &ipv6_devconf.max_desync_factor,
6657 		.maxlen		= sizeof(int),
6658 		.mode		= 0644,
6659 		.proc_handler	= proc_dointvec,
6660 	},
6661 	{
6662 		.procname	= "max_addresses",
6663 		.data		= &ipv6_devconf.max_addresses,
6664 		.maxlen		= sizeof(int),
6665 		.mode		= 0644,
6666 		.proc_handler	= proc_dointvec,
6667 	},
6668 	{
6669 		.procname	= "accept_ra_defrtr",
6670 		.data		= &ipv6_devconf.accept_ra_defrtr,
6671 		.maxlen		= sizeof(int),
6672 		.mode		= 0644,
6673 		.proc_handler	= proc_dointvec,
6674 	},
6675 	{
6676 		.procname	= "accept_ra_min_hop_limit",
6677 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6678 		.maxlen		= sizeof(int),
6679 		.mode		= 0644,
6680 		.proc_handler	= proc_dointvec,
6681 	},
6682 	{
6683 		.procname	= "accept_ra_pinfo",
6684 		.data		= &ipv6_devconf.accept_ra_pinfo,
6685 		.maxlen		= sizeof(int),
6686 		.mode		= 0644,
6687 		.proc_handler	= proc_dointvec,
6688 	},
6689 #ifdef CONFIG_IPV6_ROUTER_PREF
6690 	{
6691 		.procname	= "accept_ra_rtr_pref",
6692 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6693 		.maxlen		= sizeof(int),
6694 		.mode		= 0644,
6695 		.proc_handler	= proc_dointvec,
6696 	},
6697 	{
6698 		.procname	= "router_probe_interval",
6699 		.data		= &ipv6_devconf.rtr_probe_interval,
6700 		.maxlen		= sizeof(int),
6701 		.mode		= 0644,
6702 		.proc_handler	= proc_dointvec_jiffies,
6703 	},
6704 #ifdef CONFIG_IPV6_ROUTE_INFO
6705 	{
6706 		.procname	= "accept_ra_rt_info_min_plen",
6707 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6708 		.maxlen		= sizeof(int),
6709 		.mode		= 0644,
6710 		.proc_handler	= proc_dointvec,
6711 	},
6712 	{
6713 		.procname	= "accept_ra_rt_info_max_plen",
6714 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6715 		.maxlen		= sizeof(int),
6716 		.mode		= 0644,
6717 		.proc_handler	= proc_dointvec,
6718 	},
6719 #endif
6720 #endif
6721 	{
6722 		.procname	= "proxy_ndp",
6723 		.data		= &ipv6_devconf.proxy_ndp,
6724 		.maxlen		= sizeof(int),
6725 		.mode		= 0644,
6726 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6727 	},
6728 	{
6729 		.procname	= "accept_source_route",
6730 		.data		= &ipv6_devconf.accept_source_route,
6731 		.maxlen		= sizeof(int),
6732 		.mode		= 0644,
6733 		.proc_handler	= proc_dointvec,
6734 	},
6735 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6736 	{
6737 		.procname	= "optimistic_dad",
6738 		.data		= &ipv6_devconf.optimistic_dad,
6739 		.maxlen		= sizeof(int),
6740 		.mode		= 0644,
6741 		.proc_handler   = proc_dointvec,
6742 	},
6743 	{
6744 		.procname	= "use_optimistic",
6745 		.data		= &ipv6_devconf.use_optimistic,
6746 		.maxlen		= sizeof(int),
6747 		.mode		= 0644,
6748 		.proc_handler	= proc_dointvec,
6749 	},
6750 #endif
6751 #ifdef CONFIG_IPV6_MROUTE
6752 	{
6753 		.procname	= "mc_forwarding",
6754 		.data		= &ipv6_devconf.mc_forwarding,
6755 		.maxlen		= sizeof(int),
6756 		.mode		= 0444,
6757 		.proc_handler	= proc_dointvec,
6758 	},
6759 #endif
6760 	{
6761 		.procname	= "disable_ipv6",
6762 		.data		= &ipv6_devconf.disable_ipv6,
6763 		.maxlen		= sizeof(int),
6764 		.mode		= 0644,
6765 		.proc_handler	= addrconf_sysctl_disable,
6766 	},
6767 	{
6768 		.procname	= "accept_dad",
6769 		.data		= &ipv6_devconf.accept_dad,
6770 		.maxlen		= sizeof(int),
6771 		.mode		= 0644,
6772 		.proc_handler	= proc_dointvec,
6773 	},
6774 	{
6775 		.procname	= "force_tllao",
6776 		.data		= &ipv6_devconf.force_tllao,
6777 		.maxlen		= sizeof(int),
6778 		.mode		= 0644,
6779 		.proc_handler	= proc_dointvec
6780 	},
6781 	{
6782 		.procname	= "ndisc_notify",
6783 		.data		= &ipv6_devconf.ndisc_notify,
6784 		.maxlen		= sizeof(int),
6785 		.mode		= 0644,
6786 		.proc_handler	= proc_dointvec
6787 	},
6788 	{
6789 		.procname	= "suppress_frag_ndisc",
6790 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6791 		.maxlen		= sizeof(int),
6792 		.mode		= 0644,
6793 		.proc_handler	= proc_dointvec
6794 	},
6795 	{
6796 		.procname	= "accept_ra_from_local",
6797 		.data		= &ipv6_devconf.accept_ra_from_local,
6798 		.maxlen		= sizeof(int),
6799 		.mode		= 0644,
6800 		.proc_handler	= proc_dointvec,
6801 	},
6802 	{
6803 		.procname	= "accept_ra_mtu",
6804 		.data		= &ipv6_devconf.accept_ra_mtu,
6805 		.maxlen		= sizeof(int),
6806 		.mode		= 0644,
6807 		.proc_handler	= proc_dointvec,
6808 	},
6809 	{
6810 		.procname	= "stable_secret",
6811 		.data		= &ipv6_devconf.stable_secret,
6812 		.maxlen		= IPV6_MAX_STRLEN,
6813 		.mode		= 0600,
6814 		.proc_handler	= addrconf_sysctl_stable_secret,
6815 	},
6816 	{
6817 		.procname	= "use_oif_addrs_only",
6818 		.data		= &ipv6_devconf.use_oif_addrs_only,
6819 		.maxlen		= sizeof(int),
6820 		.mode		= 0644,
6821 		.proc_handler	= proc_dointvec,
6822 	},
6823 	{
6824 		.procname	= "ignore_routes_with_linkdown",
6825 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6826 		.maxlen		= sizeof(int),
6827 		.mode		= 0644,
6828 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6829 	},
6830 	{
6831 		.procname	= "drop_unicast_in_l2_multicast",
6832 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6833 		.maxlen		= sizeof(int),
6834 		.mode		= 0644,
6835 		.proc_handler	= proc_dointvec,
6836 	},
6837 	{
6838 		.procname	= "drop_unsolicited_na",
6839 		.data		= &ipv6_devconf.drop_unsolicited_na,
6840 		.maxlen		= sizeof(int),
6841 		.mode		= 0644,
6842 		.proc_handler	= proc_dointvec,
6843 	},
6844 	{
6845 		.procname	= "keep_addr_on_down",
6846 		.data		= &ipv6_devconf.keep_addr_on_down,
6847 		.maxlen		= sizeof(int),
6848 		.mode		= 0644,
6849 		.proc_handler	= proc_dointvec,
6850 
6851 	},
6852 	{
6853 		.procname	= "seg6_enabled",
6854 		.data		= &ipv6_devconf.seg6_enabled,
6855 		.maxlen		= sizeof(int),
6856 		.mode		= 0644,
6857 		.proc_handler	= proc_dointvec,
6858 	},
6859 #ifdef CONFIG_IPV6_SEG6_HMAC
6860 	{
6861 		.procname	= "seg6_require_hmac",
6862 		.data		= &ipv6_devconf.seg6_require_hmac,
6863 		.maxlen		= sizeof(int),
6864 		.mode		= 0644,
6865 		.proc_handler	= proc_dointvec,
6866 	},
6867 #endif
6868 	{
6869 		.procname       = "enhanced_dad",
6870 		.data           = &ipv6_devconf.enhanced_dad,
6871 		.maxlen         = sizeof(int),
6872 		.mode           = 0644,
6873 		.proc_handler   = proc_dointvec,
6874 	},
6875 	{
6876 		.procname		= "addr_gen_mode",
6877 		.data			= &ipv6_devconf.addr_gen_mode,
6878 		.maxlen			= sizeof(int),
6879 		.mode			= 0644,
6880 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6881 	},
6882 	{
6883 		.procname       = "disable_policy",
6884 		.data           = &ipv6_devconf.disable_policy,
6885 		.maxlen         = sizeof(int),
6886 		.mode           = 0644,
6887 		.proc_handler   = addrconf_sysctl_disable_policy,
6888 	},
6889 	{
6890 		.procname	= "ndisc_tclass",
6891 		.data		= &ipv6_devconf.ndisc_tclass,
6892 		.maxlen		= sizeof(int),
6893 		.mode		= 0644,
6894 		.proc_handler	= proc_dointvec_minmax,
6895 		.extra1		= (void *)SYSCTL_ZERO,
6896 		.extra2		= (void *)&two_five_five,
6897 	},
6898 	{
6899 		.procname	= "rpl_seg_enabled",
6900 		.data		= &ipv6_devconf.rpl_seg_enabled,
6901 		.maxlen		= sizeof(int),
6902 		.mode		= 0644,
6903 		.proc_handler	= proc_dointvec,
6904 	},
6905 	{
6906 		/* sentinel */
6907 	}
6908 };
6909 
6910 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6911 		struct inet6_dev *idev, struct ipv6_devconf *p)
6912 {
6913 	int i, ifindex;
6914 	struct ctl_table *table;
6915 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6916 
6917 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6918 	if (!table)
6919 		goto out;
6920 
6921 	for (i = 0; table[i].data; i++) {
6922 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6923 		/* If one of these is already set, then it is not safe to
6924 		 * overwrite either of them: this makes proc_dointvec_minmax
6925 		 * usable.
6926 		 */
6927 		if (!table[i].extra1 && !table[i].extra2) {
6928 			table[i].extra1 = idev; /* embedded; no ref */
6929 			table[i].extra2 = net;
6930 		}
6931 	}
6932 
6933 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6934 
6935 	p->sysctl_header = register_net_sysctl(net, path, table);
6936 	if (!p->sysctl_header)
6937 		goto free;
6938 
6939 	if (!strcmp(dev_name, "all"))
6940 		ifindex = NETCONFA_IFINDEX_ALL;
6941 	else if (!strcmp(dev_name, "default"))
6942 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6943 	else
6944 		ifindex = idev->dev->ifindex;
6945 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6946 				     ifindex, p);
6947 	return 0;
6948 
6949 free:
6950 	kfree(table);
6951 out:
6952 	return -ENOBUFS;
6953 }
6954 
6955 static void __addrconf_sysctl_unregister(struct net *net,
6956 					 struct ipv6_devconf *p, int ifindex)
6957 {
6958 	struct ctl_table *table;
6959 
6960 	if (!p->sysctl_header)
6961 		return;
6962 
6963 	table = p->sysctl_header->ctl_table_arg;
6964 	unregister_net_sysctl_table(p->sysctl_header);
6965 	p->sysctl_header = NULL;
6966 	kfree(table);
6967 
6968 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6969 }
6970 
6971 static int addrconf_sysctl_register(struct inet6_dev *idev)
6972 {
6973 	int err;
6974 
6975 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6976 		return -EINVAL;
6977 
6978 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6979 				    &ndisc_ifinfo_sysctl_change);
6980 	if (err)
6981 		return err;
6982 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6983 					 idev, &idev->cnf);
6984 	if (err)
6985 		neigh_sysctl_unregister(idev->nd_parms);
6986 
6987 	return err;
6988 }
6989 
6990 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6991 {
6992 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6993 				     idev->dev->ifindex);
6994 	neigh_sysctl_unregister(idev->nd_parms);
6995 }
6996 
6997 
6998 #endif
6999 
7000 static int __net_init addrconf_init_net(struct net *net)
7001 {
7002 	int err = -ENOMEM;
7003 	struct ipv6_devconf *all, *dflt;
7004 
7005 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7006 	if (!all)
7007 		goto err_alloc_all;
7008 
7009 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7010 	if (!dflt)
7011 		goto err_alloc_dflt;
7012 
7013 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7014 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
7015 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
7016 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
7017 	}
7018 
7019 	/* these will be inherited by all namespaces */
7020 	dflt->autoconf = ipv6_defaults.autoconf;
7021 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7022 
7023 	dflt->stable_secret.initialized = false;
7024 	all->stable_secret.initialized = false;
7025 
7026 	net->ipv6.devconf_all = all;
7027 	net->ipv6.devconf_dflt = dflt;
7028 
7029 #ifdef CONFIG_SYSCTL
7030 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7031 	if (err < 0)
7032 		goto err_reg_all;
7033 
7034 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7035 	if (err < 0)
7036 		goto err_reg_dflt;
7037 #endif
7038 	return 0;
7039 
7040 #ifdef CONFIG_SYSCTL
7041 err_reg_dflt:
7042 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7043 err_reg_all:
7044 	kfree(dflt);
7045 #endif
7046 err_alloc_dflt:
7047 	kfree(all);
7048 err_alloc_all:
7049 	return err;
7050 }
7051 
7052 static void __net_exit addrconf_exit_net(struct net *net)
7053 {
7054 #ifdef CONFIG_SYSCTL
7055 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7056 				     NETCONFA_IFINDEX_DEFAULT);
7057 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7058 				     NETCONFA_IFINDEX_ALL);
7059 #endif
7060 	kfree(net->ipv6.devconf_dflt);
7061 	kfree(net->ipv6.devconf_all);
7062 }
7063 
7064 static struct pernet_operations addrconf_ops = {
7065 	.init = addrconf_init_net,
7066 	.exit = addrconf_exit_net,
7067 };
7068 
7069 static struct rtnl_af_ops inet6_ops __read_mostly = {
7070 	.family		  = AF_INET6,
7071 	.fill_link_af	  = inet6_fill_link_af,
7072 	.get_link_af_size = inet6_get_link_af_size,
7073 	.validate_link_af = inet6_validate_link_af,
7074 	.set_link_af	  = inet6_set_link_af,
7075 };
7076 
7077 /*
7078  *	Init / cleanup code
7079  */
7080 
7081 int __init addrconf_init(void)
7082 {
7083 	struct inet6_dev *idev;
7084 	int i, err;
7085 
7086 	err = ipv6_addr_label_init();
7087 	if (err < 0) {
7088 		pr_crit("%s: cannot initialize default policy table: %d\n",
7089 			__func__, err);
7090 		goto out;
7091 	}
7092 
7093 	err = register_pernet_subsys(&addrconf_ops);
7094 	if (err < 0)
7095 		goto out_addrlabel;
7096 
7097 	addrconf_wq = create_workqueue("ipv6_addrconf");
7098 	if (!addrconf_wq) {
7099 		err = -ENOMEM;
7100 		goto out_nowq;
7101 	}
7102 
7103 	/* The addrconf netdev notifier requires that loopback_dev
7104 	 * has it's ipv6 private information allocated and setup
7105 	 * before it can bring up and give link-local addresses
7106 	 * to other devices which are up.
7107 	 *
7108 	 * Unfortunately, loopback_dev is not necessarily the first
7109 	 * entry in the global dev_base list of net devices.  In fact,
7110 	 * it is likely to be the very last entry on that list.
7111 	 * So this causes the notifier registry below to try and
7112 	 * give link-local addresses to all devices besides loopback_dev
7113 	 * first, then loopback_dev, which cases all the non-loopback_dev
7114 	 * devices to fail to get a link-local address.
7115 	 *
7116 	 * So, as a temporary fix, allocate the ipv6 structure for
7117 	 * loopback_dev first by hand.
7118 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7119 	 * device and it being up should be removed.
7120 	 */
7121 	rtnl_lock();
7122 	idev = ipv6_add_dev(init_net.loopback_dev);
7123 	rtnl_unlock();
7124 	if (IS_ERR(idev)) {
7125 		err = PTR_ERR(idev);
7126 		goto errlo;
7127 	}
7128 
7129 	ip6_route_init_special_entries();
7130 
7131 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7132 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7133 
7134 	register_netdevice_notifier(&ipv6_dev_notf);
7135 
7136 	addrconf_verify();
7137 
7138 	rtnl_af_register(&inet6_ops);
7139 
7140 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7141 				   NULL, inet6_dump_ifinfo, 0);
7142 	if (err < 0)
7143 		goto errout;
7144 
7145 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7146 				   inet6_rtm_newaddr, NULL, 0);
7147 	if (err < 0)
7148 		goto errout;
7149 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7150 				   inet6_rtm_deladdr, NULL, 0);
7151 	if (err < 0)
7152 		goto errout;
7153 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7154 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7155 				   RTNL_FLAG_DOIT_UNLOCKED);
7156 	if (err < 0)
7157 		goto errout;
7158 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7159 				   NULL, inet6_dump_ifmcaddr, 0);
7160 	if (err < 0)
7161 		goto errout;
7162 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7163 				   NULL, inet6_dump_ifacaddr, 0);
7164 	if (err < 0)
7165 		goto errout;
7166 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7167 				   inet6_netconf_get_devconf,
7168 				   inet6_netconf_dump_devconf,
7169 				   RTNL_FLAG_DOIT_UNLOCKED);
7170 	if (err < 0)
7171 		goto errout;
7172 	err = ipv6_addr_label_rtnl_register();
7173 	if (err < 0)
7174 		goto errout;
7175 
7176 	return 0;
7177 errout:
7178 	rtnl_unregister_all(PF_INET6);
7179 	rtnl_af_unregister(&inet6_ops);
7180 	unregister_netdevice_notifier(&ipv6_dev_notf);
7181 errlo:
7182 	destroy_workqueue(addrconf_wq);
7183 out_nowq:
7184 	unregister_pernet_subsys(&addrconf_ops);
7185 out_addrlabel:
7186 	ipv6_addr_label_cleanup();
7187 out:
7188 	return err;
7189 }
7190 
7191 void addrconf_cleanup(void)
7192 {
7193 	struct net_device *dev;
7194 	int i;
7195 
7196 	unregister_netdevice_notifier(&ipv6_dev_notf);
7197 	unregister_pernet_subsys(&addrconf_ops);
7198 	ipv6_addr_label_cleanup();
7199 
7200 	rtnl_af_unregister(&inet6_ops);
7201 
7202 	rtnl_lock();
7203 
7204 	/* clean dev list */
7205 	for_each_netdev(&init_net, dev) {
7206 		if (__in6_dev_get(dev) == NULL)
7207 			continue;
7208 		addrconf_ifdown(dev, 1);
7209 	}
7210 	addrconf_ifdown(init_net.loopback_dev, 2);
7211 
7212 	/*
7213 	 *	Check hash table.
7214 	 */
7215 	spin_lock_bh(&addrconf_hash_lock);
7216 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7217 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7218 	spin_unlock_bh(&addrconf_hash_lock);
7219 	cancel_delayed_work(&addr_chk_work);
7220 	rtnl_unlock();
7221 
7222 	destroy_workqueue(addrconf_wq);
7223 }
7224