xref: /openbmc/linux/net/ipv6/addrconf.c (revision 0bf49ffb)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
139 
140 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
141 static int ipv6_count_addresses(const struct inet6_dev *idev);
142 static int ipv6_generate_stable_address(struct in6_addr *addr,
143 					u8 dad_count,
144 					const struct inet6_dev *idev);
145 
146 #define IN6_ADDR_HSIZE_SHIFT	8
147 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
148 /*
149  *	Configured unicast address hash table
150  */
151 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
152 static DEFINE_SPINLOCK(addrconf_hash_lock);
153 
154 static void addrconf_verify(void);
155 static void addrconf_verify_rtnl(void);
156 static void addrconf_verify_work(struct work_struct *);
157 
158 static struct workqueue_struct *addrconf_wq;
159 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
160 
161 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
162 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
163 
164 static void addrconf_type_change(struct net_device *dev,
165 				 unsigned long event);
166 static int addrconf_ifdown(struct net_device *dev, bool unregister);
167 
168 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
169 						  int plen,
170 						  const struct net_device *dev,
171 						  u32 flags, u32 noflags,
172 						  bool no_gw);
173 
174 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
175 static void addrconf_dad_work(struct work_struct *w);
176 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
177 				   bool send_na);
178 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
179 static void addrconf_rs_timer(struct timer_list *t);
180 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
181 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 
183 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
184 				struct prefix_info *pinfo);
185 
186 static struct ipv6_devconf ipv6_devconf __read_mostly = {
187 	.forwarding		= 0,
188 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
189 	.mtu6			= IPV6_MIN_MTU,
190 	.accept_ra		= 1,
191 	.accept_redirects	= 1,
192 	.autoconf		= 1,
193 	.force_mld_version	= 0,
194 	.mldv1_unsolicited_report_interval = 10 * HZ,
195 	.mldv2_unsolicited_report_interval = HZ,
196 	.dad_transmits		= 1,
197 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
198 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
199 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
200 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
201 	.use_tempaddr		= 0,
202 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
203 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
204 	.regen_max_retry	= REGEN_MAX_RETRY,
205 	.max_desync_factor	= MAX_DESYNC_FACTOR,
206 	.max_addresses		= IPV6_MAX_ADDRESSES,
207 	.accept_ra_defrtr	= 1,
208 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
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 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
265 	.accept_ra_from_local	= 0,
266 	.accept_ra_min_hop_limit= 1,
267 	.accept_ra_pinfo	= 1,
268 #ifdef CONFIG_IPV6_ROUTER_PREF
269 	.accept_ra_rtr_pref	= 1,
270 	.rtr_probe_interval	= 60 * HZ,
271 #ifdef CONFIG_IPV6_ROUTE_INFO
272 	.accept_ra_rt_info_min_plen = 0,
273 	.accept_ra_rt_info_max_plen = 0,
274 #endif
275 #endif
276 	.proxy_ndp		= 0,
277 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
278 	.disable_ipv6		= 0,
279 	.accept_dad		= 1,
280 	.suppress_frag_ndisc	= 1,
281 	.accept_ra_mtu		= 1,
282 	.stable_secret		= {
283 		.initialized = false,
284 	},
285 	.use_oif_addrs_only	= 0,
286 	.ignore_routes_with_linkdown = 0,
287 	.keep_addr_on_down	= 0,
288 	.seg6_enabled		= 0,
289 #ifdef CONFIG_IPV6_SEG6_HMAC
290 	.seg6_require_hmac	= 0,
291 #endif
292 	.enhanced_dad           = 1,
293 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
294 	.disable_policy		= 0,
295 	.rpl_seg_enabled	= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 
389 	ndev->cnf.mtu6 = dev->mtu;
390 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
391 	if (!ndev->nd_parms) {
392 		kfree(ndev);
393 		return ERR_PTR(err);
394 	}
395 	if (ndev->cnf.forwarding)
396 		dev_disable_lro(dev);
397 	/* We refer to the device */
398 	dev_hold(dev);
399 
400 	if (snmp6_alloc_dev(ndev) < 0) {
401 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
402 			   __func__);
403 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
404 		dev_put(dev);
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 
409 	if (snmp6_register_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
411 			   __func__, dev->name);
412 		goto err_release;
413 	}
414 
415 	/* One reference from device. */
416 	refcount_set(&ndev->refcnt, 1);
417 
418 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
419 		ndev->cnf.accept_dad = -1;
420 
421 #if IS_ENABLED(CONFIG_IPV6_SIT)
422 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
423 		pr_info("%s: Disabled Multicast RS\n", dev->name);
424 		ndev->cnf.rtr_solicits = 0;
425 	}
426 #endif
427 
428 	INIT_LIST_HEAD(&ndev->tempaddr_list);
429 	ndev->desync_factor = U32_MAX;
430 	if ((dev->flags&IFF_LOOPBACK) ||
431 	    dev->type == ARPHRD_TUNNEL ||
432 	    dev->type == ARPHRD_TUNNEL6 ||
433 	    dev->type == ARPHRD_SIT ||
434 	    dev->type == ARPHRD_NONE) {
435 		ndev->cnf.use_tempaddr = -1;
436 	}
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, bool block)
1310 {
1311 	struct inet6_dev *idev = ifp->idev;
1312 	unsigned long tmp_tstamp, age;
1313 	unsigned long regen_advance;
1314 	unsigned long now = jiffies;
1315 	s32 cnf_temp_preferred_lft;
1316 	struct inet6_ifaddr *ift;
1317 	struct ifa6_config cfg;
1318 	long max_desync_factor;
1319 	struct in6_addr addr;
1320 	int ret = 0;
1321 
1322 	write_lock_bh(&idev->lock);
1323 
1324 retry:
1325 	in6_dev_hold(idev);
1326 	if (idev->cnf.use_tempaddr <= 0) {
1327 		write_unlock_bh(&idev->lock);
1328 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1329 		in6_dev_put(idev);
1330 		ret = -1;
1331 		goto out;
1332 	}
1333 	spin_lock_bh(&ifp->lock);
1334 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1335 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1336 		spin_unlock_bh(&ifp->lock);
1337 		write_unlock_bh(&idev->lock);
1338 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1339 			__func__);
1340 		in6_dev_put(idev);
1341 		ret = -1;
1342 		goto out;
1343 	}
1344 	in6_ifa_hold(ifp);
1345 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1346 	ipv6_gen_rnd_iid(&addr);
1347 
1348 	age = (now - ifp->tstamp) / HZ;
1349 
1350 	regen_advance = idev->cnf.regen_max_retry *
1351 			idev->cnf.dad_transmits *
1352 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1353 
1354 	/* recalculate max_desync_factor each time and update
1355 	 * idev->desync_factor if it's larger
1356 	 */
1357 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1358 	max_desync_factor = min_t(__u32,
1359 				  idev->cnf.max_desync_factor,
1360 				  cnf_temp_preferred_lft - regen_advance);
1361 
1362 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1363 		if (max_desync_factor > 0) {
1364 			get_random_bytes(&idev->desync_factor,
1365 					 sizeof(idev->desync_factor));
1366 			idev->desync_factor %= max_desync_factor;
1367 		} else {
1368 			idev->desync_factor = 0;
1369 		}
1370 	}
1371 
1372 	memset(&cfg, 0, sizeof(cfg));
1373 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1374 			      idev->cnf.temp_valid_lft + age);
1375 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1376 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1377 
1378 	cfg.plen = ifp->prefix_len;
1379 	tmp_tstamp = ifp->tstamp;
1380 	spin_unlock_bh(&ifp->lock);
1381 
1382 	write_unlock_bh(&idev->lock);
1383 
1384 	/* A temporary address is created only if this calculated Preferred
1385 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1386 	 * an implementation must not create a temporary address with a zero
1387 	 * Preferred Lifetime.
1388 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1389 	 * temporary addresses being generated.
1390 	 */
1391 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1392 	if (cfg.preferred_lft <= regen_advance + age) {
1393 		in6_ifa_put(ifp);
1394 		in6_dev_put(idev);
1395 		ret = -1;
1396 		goto out;
1397 	}
1398 
1399 	cfg.ifa_flags = IFA_F_TEMPORARY;
1400 	/* set in addrconf_prefix_rcv() */
1401 	if (ifp->flags & IFA_F_OPTIMISTIC)
1402 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1403 
1404 	cfg.pfx = &addr;
1405 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1406 
1407 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1408 	if (IS_ERR(ift)) {
1409 		in6_ifa_put(ifp);
1410 		in6_dev_put(idev);
1411 		pr_info("%s: retry temporary address regeneration\n", __func__);
1412 		write_lock_bh(&idev->lock);
1413 		goto retry;
1414 	}
1415 
1416 	spin_lock_bh(&ift->lock);
1417 	ift->ifpub = ifp;
1418 	ift->cstamp = now;
1419 	ift->tstamp = tmp_tstamp;
1420 	spin_unlock_bh(&ift->lock);
1421 
1422 	addrconf_dad_start(ift);
1423 	in6_ifa_put(ift);
1424 	in6_dev_put(idev);
1425 out:
1426 	return ret;
1427 }
1428 
1429 /*
1430  *	Choose an appropriate source address (RFC3484)
1431  */
1432 enum {
1433 	IPV6_SADDR_RULE_INIT = 0,
1434 	IPV6_SADDR_RULE_LOCAL,
1435 	IPV6_SADDR_RULE_SCOPE,
1436 	IPV6_SADDR_RULE_PREFERRED,
1437 #ifdef CONFIG_IPV6_MIP6
1438 	IPV6_SADDR_RULE_HOA,
1439 #endif
1440 	IPV6_SADDR_RULE_OIF,
1441 	IPV6_SADDR_RULE_LABEL,
1442 	IPV6_SADDR_RULE_PRIVACY,
1443 	IPV6_SADDR_RULE_ORCHID,
1444 	IPV6_SADDR_RULE_PREFIX,
1445 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1446 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1447 #endif
1448 	IPV6_SADDR_RULE_MAX
1449 };
1450 
1451 struct ipv6_saddr_score {
1452 	int			rule;
1453 	int			addr_type;
1454 	struct inet6_ifaddr	*ifa;
1455 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1456 	int			scopedist;
1457 	int			matchlen;
1458 };
1459 
1460 struct ipv6_saddr_dst {
1461 	const struct in6_addr *addr;
1462 	int ifindex;
1463 	int scope;
1464 	int label;
1465 	unsigned int prefs;
1466 };
1467 
1468 static inline int ipv6_saddr_preferred(int type)
1469 {
1470 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1471 		return 1;
1472 	return 0;
1473 }
1474 
1475 static bool ipv6_use_optimistic_addr(struct net *net,
1476 				     struct inet6_dev *idev)
1477 {
1478 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1479 	if (!idev)
1480 		return false;
1481 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1482 		return false;
1483 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1484 		return false;
1485 
1486 	return true;
1487 #else
1488 	return false;
1489 #endif
1490 }
1491 
1492 static bool ipv6_allow_optimistic_dad(struct net *net,
1493 				      struct inet6_dev *idev)
1494 {
1495 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1496 	if (!idev)
1497 		return false;
1498 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1499 		return false;
1500 
1501 	return true;
1502 #else
1503 	return false;
1504 #endif
1505 }
1506 
1507 static int ipv6_get_saddr_eval(struct net *net,
1508 			       struct ipv6_saddr_score *score,
1509 			       struct ipv6_saddr_dst *dst,
1510 			       int i)
1511 {
1512 	int ret;
1513 
1514 	if (i <= score->rule) {
1515 		switch (i) {
1516 		case IPV6_SADDR_RULE_SCOPE:
1517 			ret = score->scopedist;
1518 			break;
1519 		case IPV6_SADDR_RULE_PREFIX:
1520 			ret = score->matchlen;
1521 			break;
1522 		default:
1523 			ret = !!test_bit(i, score->scorebits);
1524 		}
1525 		goto out;
1526 	}
1527 
1528 	switch (i) {
1529 	case IPV6_SADDR_RULE_INIT:
1530 		/* Rule 0: remember if hiscore is not ready yet */
1531 		ret = !!score->ifa;
1532 		break;
1533 	case IPV6_SADDR_RULE_LOCAL:
1534 		/* Rule 1: Prefer same address */
1535 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1536 		break;
1537 	case IPV6_SADDR_RULE_SCOPE:
1538 		/* Rule 2: Prefer appropriate scope
1539 		 *
1540 		 *      ret
1541 		 *       ^
1542 		 *    -1 |  d 15
1543 		 *    ---+--+-+---> scope
1544 		 *       |
1545 		 *       |             d is scope of the destination.
1546 		 *  B-d  |  \
1547 		 *       |   \      <- smaller scope is better if
1548 		 *  B-15 |    \        if scope is enough for destination.
1549 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1550 		 * d-C-1 | /
1551 		 *       |/         <- greater is better
1552 		 *   -C  /             if scope is not enough for destination.
1553 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1554 		 *
1555 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1556 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1557 		 * Assume B = 0 and we get C > 29.
1558 		 */
1559 		ret = __ipv6_addr_src_scope(score->addr_type);
1560 		if (ret >= dst->scope)
1561 			ret = -ret;
1562 		else
1563 			ret -= 128;	/* 30 is enough */
1564 		score->scopedist = ret;
1565 		break;
1566 	case IPV6_SADDR_RULE_PREFERRED:
1567 	    {
1568 		/* Rule 3: Avoid deprecated and optimistic addresses */
1569 		u8 avoid = IFA_F_DEPRECATED;
1570 
1571 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1572 			avoid |= IFA_F_OPTIMISTIC;
1573 		ret = ipv6_saddr_preferred(score->addr_type) ||
1574 		      !(score->ifa->flags & avoid);
1575 		break;
1576 	    }
1577 #ifdef CONFIG_IPV6_MIP6
1578 	case IPV6_SADDR_RULE_HOA:
1579 	    {
1580 		/* Rule 4: Prefer home address */
1581 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1582 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1583 		break;
1584 	    }
1585 #endif
1586 	case IPV6_SADDR_RULE_OIF:
1587 		/* Rule 5: Prefer outgoing interface */
1588 		ret = (!dst->ifindex ||
1589 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1590 		break;
1591 	case IPV6_SADDR_RULE_LABEL:
1592 		/* Rule 6: Prefer matching label */
1593 		ret = ipv6_addr_label(net,
1594 				      &score->ifa->addr, score->addr_type,
1595 				      score->ifa->idev->dev->ifindex) == dst->label;
1596 		break;
1597 	case IPV6_SADDR_RULE_PRIVACY:
1598 	    {
1599 		/* Rule 7: Prefer public address
1600 		 * Note: prefer temporary address if use_tempaddr >= 2
1601 		 */
1602 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1603 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1604 				score->ifa->idev->cnf.use_tempaddr >= 2;
1605 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1606 		break;
1607 	    }
1608 	case IPV6_SADDR_RULE_ORCHID:
1609 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1610 		 *	    non-ORCHID vs non-ORCHID
1611 		 */
1612 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1613 			ipv6_addr_orchid(dst->addr));
1614 		break;
1615 	case IPV6_SADDR_RULE_PREFIX:
1616 		/* Rule 8: Use longest matching prefix */
1617 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1618 		if (ret > score->ifa->prefix_len)
1619 			ret = score->ifa->prefix_len;
1620 		score->matchlen = ret;
1621 		break;
1622 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1623 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1624 		/* Optimistic addresses still have lower precedence than other
1625 		 * preferred addresses.
1626 		 */
1627 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1628 		break;
1629 #endif
1630 	default:
1631 		ret = 0;
1632 	}
1633 
1634 	if (ret)
1635 		__set_bit(i, score->scorebits);
1636 	score->rule = i;
1637 out:
1638 	return ret;
1639 }
1640 
1641 static int __ipv6_dev_get_saddr(struct net *net,
1642 				struct ipv6_saddr_dst *dst,
1643 				struct inet6_dev *idev,
1644 				struct ipv6_saddr_score *scores,
1645 				int hiscore_idx)
1646 {
1647 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1648 
1649 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1650 		int i;
1651 
1652 		/*
1653 		 * - Tentative Address (RFC2462 section 5.4)
1654 		 *  - A tentative address is not considered
1655 		 *    "assigned to an interface" in the traditional
1656 		 *    sense, unless it is also flagged as optimistic.
1657 		 * - Candidate Source Address (section 4)
1658 		 *  - In any case, anycast addresses, multicast
1659 		 *    addresses, and the unspecified address MUST
1660 		 *    NOT be included in a candidate set.
1661 		 */
1662 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1663 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1664 			continue;
1665 
1666 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1667 
1668 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1669 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1670 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1671 					    idev->dev->name);
1672 			continue;
1673 		}
1674 
1675 		score->rule = -1;
1676 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1677 
1678 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1679 			int minihiscore, miniscore;
1680 
1681 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1682 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1683 
1684 			if (minihiscore > miniscore) {
1685 				if (i == IPV6_SADDR_RULE_SCOPE &&
1686 				    score->scopedist > 0) {
1687 					/*
1688 					 * special case:
1689 					 * each remaining entry
1690 					 * has too small (not enough)
1691 					 * scope, because ifa entries
1692 					 * are sorted by their scope
1693 					 * values.
1694 					 */
1695 					goto out;
1696 				}
1697 				break;
1698 			} else if (minihiscore < miniscore) {
1699 				swap(hiscore, score);
1700 				hiscore_idx = 1 - hiscore_idx;
1701 
1702 				/* restore our iterator */
1703 				score->ifa = hiscore->ifa;
1704 
1705 				break;
1706 			}
1707 		}
1708 	}
1709 out:
1710 	return hiscore_idx;
1711 }
1712 
1713 static int ipv6_get_saddr_master(struct net *net,
1714 				 const struct net_device *dst_dev,
1715 				 const struct net_device *master,
1716 				 struct ipv6_saddr_dst *dst,
1717 				 struct ipv6_saddr_score *scores,
1718 				 int hiscore_idx)
1719 {
1720 	struct inet6_dev *idev;
1721 
1722 	idev = __in6_dev_get(dst_dev);
1723 	if (idev)
1724 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1725 						   scores, hiscore_idx);
1726 
1727 	idev = __in6_dev_get(master);
1728 	if (idev)
1729 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1730 						   scores, hiscore_idx);
1731 
1732 	return hiscore_idx;
1733 }
1734 
1735 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1736 		       const struct in6_addr *daddr, unsigned int prefs,
1737 		       struct in6_addr *saddr)
1738 {
1739 	struct ipv6_saddr_score scores[2], *hiscore;
1740 	struct ipv6_saddr_dst dst;
1741 	struct inet6_dev *idev;
1742 	struct net_device *dev;
1743 	int dst_type;
1744 	bool use_oif_addr = false;
1745 	int hiscore_idx = 0;
1746 	int ret = 0;
1747 
1748 	dst_type = __ipv6_addr_type(daddr);
1749 	dst.addr = daddr;
1750 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1751 	dst.scope = __ipv6_addr_src_scope(dst_type);
1752 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1753 	dst.prefs = prefs;
1754 
1755 	scores[hiscore_idx].rule = -1;
1756 	scores[hiscore_idx].ifa = NULL;
1757 
1758 	rcu_read_lock();
1759 
1760 	/* Candidate Source Address (section 4)
1761 	 *  - multicast and link-local destination address,
1762 	 *    the set of candidate source address MUST only
1763 	 *    include addresses assigned to interfaces
1764 	 *    belonging to the same link as the outgoing
1765 	 *    interface.
1766 	 * (- For site-local destination addresses, the
1767 	 *    set of candidate source addresses MUST only
1768 	 *    include addresses assigned to interfaces
1769 	 *    belonging to the same site as the outgoing
1770 	 *    interface.)
1771 	 *  - "It is RECOMMENDED that the candidate source addresses
1772 	 *    be the set of unicast addresses assigned to the
1773 	 *    interface that will be used to send to the destination
1774 	 *    (the 'outgoing' interface)." (RFC 6724)
1775 	 */
1776 	if (dst_dev) {
1777 		idev = __in6_dev_get(dst_dev);
1778 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1779 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1780 		    (idev && idev->cnf.use_oif_addrs_only)) {
1781 			use_oif_addr = true;
1782 		}
1783 	}
1784 
1785 	if (use_oif_addr) {
1786 		if (idev)
1787 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1788 	} else {
1789 		const struct net_device *master;
1790 		int master_idx = 0;
1791 
1792 		/* if dst_dev exists and is enslaved to an L3 device, then
1793 		 * prefer addresses from dst_dev and then the master over
1794 		 * any other enslaved devices in the L3 domain.
1795 		 */
1796 		master = l3mdev_master_dev_rcu(dst_dev);
1797 		if (master) {
1798 			master_idx = master->ifindex;
1799 
1800 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1801 							    master, &dst,
1802 							    scores, hiscore_idx);
1803 
1804 			if (scores[hiscore_idx].ifa)
1805 				goto out;
1806 		}
1807 
1808 		for_each_netdev_rcu(net, dev) {
1809 			/* only consider addresses on devices in the
1810 			 * same L3 domain
1811 			 */
1812 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1813 				continue;
1814 			idev = __in6_dev_get(dev);
1815 			if (!idev)
1816 				continue;
1817 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1818 		}
1819 	}
1820 
1821 out:
1822 	hiscore = &scores[hiscore_idx];
1823 	if (!hiscore->ifa)
1824 		ret = -EADDRNOTAVAIL;
1825 	else
1826 		*saddr = hiscore->ifa->addr;
1827 
1828 	rcu_read_unlock();
1829 	return ret;
1830 }
1831 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1832 
1833 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1834 		      u32 banned_flags)
1835 {
1836 	struct inet6_ifaddr *ifp;
1837 	int err = -EADDRNOTAVAIL;
1838 
1839 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1840 		if (ifp->scope > IFA_LINK)
1841 			break;
1842 		if (ifp->scope == IFA_LINK &&
1843 		    !(ifp->flags & banned_flags)) {
1844 			*addr = ifp->addr;
1845 			err = 0;
1846 			break;
1847 		}
1848 	}
1849 	return err;
1850 }
1851 
1852 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1853 		    u32 banned_flags)
1854 {
1855 	struct inet6_dev *idev;
1856 	int err = -EADDRNOTAVAIL;
1857 
1858 	rcu_read_lock();
1859 	idev = __in6_dev_get(dev);
1860 	if (idev) {
1861 		read_lock_bh(&idev->lock);
1862 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1863 		read_unlock_bh(&idev->lock);
1864 	}
1865 	rcu_read_unlock();
1866 	return err;
1867 }
1868 
1869 static int ipv6_count_addresses(const struct inet6_dev *idev)
1870 {
1871 	const struct inet6_ifaddr *ifp;
1872 	int cnt = 0;
1873 
1874 	rcu_read_lock();
1875 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1876 		cnt++;
1877 	rcu_read_unlock();
1878 	return cnt;
1879 }
1880 
1881 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1882 		  const struct net_device *dev, int strict)
1883 {
1884 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1885 				       strict, IFA_F_TENTATIVE);
1886 }
1887 EXPORT_SYMBOL(ipv6_chk_addr);
1888 
1889 /* device argument is used to find the L3 domain of interest. If
1890  * skip_dev_check is set, then the ifp device is not checked against
1891  * the passed in dev argument. So the 2 cases for addresses checks are:
1892  *   1. does the address exist in the L3 domain that dev is part of
1893  *      (skip_dev_check = true), or
1894  *
1895  *   2. does the address exist on the specific device
1896  *      (skip_dev_check = false)
1897  */
1898 static struct net_device *
1899 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1900 			  const struct net_device *dev, bool skip_dev_check,
1901 			  int strict, u32 banned_flags)
1902 {
1903 	unsigned int hash = inet6_addr_hash(net, addr);
1904 	struct net_device *l3mdev, *ndev;
1905 	struct inet6_ifaddr *ifp;
1906 	u32 ifp_flags;
1907 
1908 	rcu_read_lock();
1909 
1910 	l3mdev = l3mdev_master_dev_rcu(dev);
1911 	if (skip_dev_check)
1912 		dev = NULL;
1913 
1914 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1915 		ndev = ifp->idev->dev;
1916 		if (!net_eq(dev_net(ndev), net))
1917 			continue;
1918 
1919 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1920 			continue;
1921 
1922 		/* Decouple optimistic from tentative for evaluation here.
1923 		 * Ban optimistic addresses explicitly, when required.
1924 		 */
1925 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1926 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1927 			    : ifp->flags;
1928 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1929 		    !(ifp_flags&banned_flags) &&
1930 		    (!dev || ndev == dev ||
1931 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1932 			rcu_read_unlock();
1933 			return ndev;
1934 		}
1935 	}
1936 
1937 	rcu_read_unlock();
1938 	return NULL;
1939 }
1940 
1941 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1942 			    const struct net_device *dev, bool skip_dev_check,
1943 			    int strict, u32 banned_flags)
1944 {
1945 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1946 					 strict, banned_flags) ? 1 : 0;
1947 }
1948 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1949 
1950 
1951 /* Compares an address/prefix_len with addresses on device @dev.
1952  * If one is found it returns true.
1953  */
1954 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1955 	const unsigned int prefix_len, struct net_device *dev)
1956 {
1957 	const struct inet6_ifaddr *ifa;
1958 	const struct inet6_dev *idev;
1959 	bool ret = false;
1960 
1961 	rcu_read_lock();
1962 	idev = __in6_dev_get(dev);
1963 	if (idev) {
1964 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1965 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1966 			if (ret)
1967 				break;
1968 		}
1969 	}
1970 	rcu_read_unlock();
1971 
1972 	return ret;
1973 }
1974 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1975 
1976 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1977 {
1978 	const struct inet6_ifaddr *ifa;
1979 	const struct inet6_dev *idev;
1980 	int	onlink;
1981 
1982 	onlink = 0;
1983 	rcu_read_lock();
1984 	idev = __in6_dev_get(dev);
1985 	if (idev) {
1986 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1987 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1988 						   ifa->prefix_len);
1989 			if (onlink)
1990 				break;
1991 		}
1992 	}
1993 	rcu_read_unlock();
1994 	return onlink;
1995 }
1996 EXPORT_SYMBOL(ipv6_chk_prefix);
1997 
1998 /**
1999  * ipv6_dev_find - find the first device with a given source address.
2000  * @net: the net namespace
2001  * @addr: the source address
2002  * @dev: used to find the L3 domain of interest
2003  *
2004  * The caller should be protected by RCU, or RTNL.
2005  */
2006 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2007 				 struct net_device *dev)
2008 {
2009 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2010 					 IFA_F_TENTATIVE);
2011 }
2012 EXPORT_SYMBOL(ipv6_dev_find);
2013 
2014 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2015 				     struct net_device *dev, int strict)
2016 {
2017 	unsigned int hash = inet6_addr_hash(net, addr);
2018 	struct inet6_ifaddr *ifp, *result = NULL;
2019 
2020 	rcu_read_lock();
2021 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2022 		if (!net_eq(dev_net(ifp->idev->dev), net))
2023 			continue;
2024 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2025 			if (!dev || ifp->idev->dev == dev ||
2026 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2027 				result = ifp;
2028 				in6_ifa_hold(ifp);
2029 				break;
2030 			}
2031 		}
2032 	}
2033 	rcu_read_unlock();
2034 
2035 	return result;
2036 }
2037 
2038 /* Gets referenced address, destroys ifaddr */
2039 
2040 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2041 {
2042 	if (dad_failed)
2043 		ifp->flags |= IFA_F_DADFAILED;
2044 
2045 	if (ifp->flags&IFA_F_TEMPORARY) {
2046 		struct inet6_ifaddr *ifpub;
2047 		spin_lock_bh(&ifp->lock);
2048 		ifpub = ifp->ifpub;
2049 		if (ifpub) {
2050 			in6_ifa_hold(ifpub);
2051 			spin_unlock_bh(&ifp->lock);
2052 			ipv6_create_tempaddr(ifpub, true);
2053 			in6_ifa_put(ifpub);
2054 		} else {
2055 			spin_unlock_bh(&ifp->lock);
2056 		}
2057 		ipv6_del_addr(ifp);
2058 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2059 		spin_lock_bh(&ifp->lock);
2060 		addrconf_del_dad_work(ifp);
2061 		ifp->flags |= IFA_F_TENTATIVE;
2062 		if (dad_failed)
2063 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2064 		spin_unlock_bh(&ifp->lock);
2065 		if (dad_failed)
2066 			ipv6_ifa_notify(0, ifp);
2067 		in6_ifa_put(ifp);
2068 	} else {
2069 		ipv6_del_addr(ifp);
2070 	}
2071 }
2072 
2073 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2074 {
2075 	int err = -ENOENT;
2076 
2077 	spin_lock_bh(&ifp->lock);
2078 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2079 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2080 		err = 0;
2081 	}
2082 	spin_unlock_bh(&ifp->lock);
2083 
2084 	return err;
2085 }
2086 
2087 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2088 {
2089 	struct inet6_dev *idev = ifp->idev;
2090 	struct net *net = dev_net(ifp->idev->dev);
2091 
2092 	if (addrconf_dad_end(ifp)) {
2093 		in6_ifa_put(ifp);
2094 		return;
2095 	}
2096 
2097 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2098 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2099 
2100 	spin_lock_bh(&ifp->lock);
2101 
2102 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2103 		struct in6_addr new_addr;
2104 		struct inet6_ifaddr *ifp2;
2105 		int retries = ifp->stable_privacy_retry + 1;
2106 		struct ifa6_config cfg = {
2107 			.pfx = &new_addr,
2108 			.plen = ifp->prefix_len,
2109 			.ifa_flags = ifp->flags,
2110 			.valid_lft = ifp->valid_lft,
2111 			.preferred_lft = ifp->prefered_lft,
2112 			.scope = ifp->scope,
2113 		};
2114 
2115 		if (retries > net->ipv6.sysctl.idgen_retries) {
2116 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2117 					     ifp->idev->dev->name);
2118 			goto errdad;
2119 		}
2120 
2121 		new_addr = ifp->addr;
2122 		if (ipv6_generate_stable_address(&new_addr, retries,
2123 						 idev))
2124 			goto errdad;
2125 
2126 		spin_unlock_bh(&ifp->lock);
2127 
2128 		if (idev->cnf.max_addresses &&
2129 		    ipv6_count_addresses(idev) >=
2130 		    idev->cnf.max_addresses)
2131 			goto lock_errdad;
2132 
2133 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2134 				     ifp->idev->dev->name);
2135 
2136 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2137 		if (IS_ERR(ifp2))
2138 			goto lock_errdad;
2139 
2140 		spin_lock_bh(&ifp2->lock);
2141 		ifp2->stable_privacy_retry = retries;
2142 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2143 		spin_unlock_bh(&ifp2->lock);
2144 
2145 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2146 		in6_ifa_put(ifp2);
2147 lock_errdad:
2148 		spin_lock_bh(&ifp->lock);
2149 	}
2150 
2151 errdad:
2152 	/* transition from _POSTDAD to _ERRDAD */
2153 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2154 	spin_unlock_bh(&ifp->lock);
2155 
2156 	addrconf_mod_dad_work(ifp, 0);
2157 	in6_ifa_put(ifp);
2158 }
2159 
2160 /* Join to solicited addr multicast group.
2161  * caller must hold RTNL */
2162 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2163 {
2164 	struct in6_addr maddr;
2165 
2166 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2167 		return;
2168 
2169 	addrconf_addr_solict_mult(addr, &maddr);
2170 	ipv6_dev_mc_inc(dev, &maddr);
2171 }
2172 
2173 /* caller must hold RTNL */
2174 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2175 {
2176 	struct in6_addr maddr;
2177 
2178 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2179 		return;
2180 
2181 	addrconf_addr_solict_mult(addr, &maddr);
2182 	__ipv6_dev_mc_dec(idev, &maddr);
2183 }
2184 
2185 /* caller must hold RTNL */
2186 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2187 {
2188 	struct in6_addr addr;
2189 
2190 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2191 		return;
2192 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2193 	if (ipv6_addr_any(&addr))
2194 		return;
2195 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2196 }
2197 
2198 /* caller must hold RTNL */
2199 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2200 {
2201 	struct in6_addr addr;
2202 
2203 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2204 		return;
2205 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2206 	if (ipv6_addr_any(&addr))
2207 		return;
2208 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2209 }
2210 
2211 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2212 {
2213 	switch (dev->addr_len) {
2214 	case ETH_ALEN:
2215 		memcpy(eui, dev->dev_addr, 3);
2216 		eui[3] = 0xFF;
2217 		eui[4] = 0xFE;
2218 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2219 		break;
2220 	case EUI64_ADDR_LEN:
2221 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2222 		eui[0] ^= 2;
2223 		break;
2224 	default:
2225 		return -1;
2226 	}
2227 
2228 	return 0;
2229 }
2230 
2231 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2232 {
2233 	union fwnet_hwaddr *ha;
2234 
2235 	if (dev->addr_len != FWNET_ALEN)
2236 		return -1;
2237 
2238 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2239 
2240 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2241 	eui[0] ^= 2;
2242 	return 0;
2243 }
2244 
2245 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2246 {
2247 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2248 	if (dev->addr_len != ARCNET_ALEN)
2249 		return -1;
2250 	memset(eui, 0, 7);
2251 	eui[7] = *(u8 *)dev->dev_addr;
2252 	return 0;
2253 }
2254 
2255 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2256 {
2257 	if (dev->addr_len != INFINIBAND_ALEN)
2258 		return -1;
2259 	memcpy(eui, dev->dev_addr + 12, 8);
2260 	eui[0] |= 2;
2261 	return 0;
2262 }
2263 
2264 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2265 {
2266 	if (addr == 0)
2267 		return -1;
2268 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2269 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2270 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2271 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2272 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2273 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2274 	eui[1] = 0;
2275 	eui[2] = 0x5E;
2276 	eui[3] = 0xFE;
2277 	memcpy(eui + 4, &addr, 4);
2278 	return 0;
2279 }
2280 
2281 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2282 {
2283 	if (dev->priv_flags & IFF_ISATAP)
2284 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2285 	return -1;
2286 }
2287 
2288 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2289 {
2290 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2291 }
2292 
2293 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2294 {
2295 	memcpy(eui, dev->perm_addr, 3);
2296 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2297 	eui[3] = 0xFF;
2298 	eui[4] = 0xFE;
2299 	eui[0] ^= 2;
2300 	return 0;
2301 }
2302 
2303 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2304 {
2305 	switch (dev->type) {
2306 	case ARPHRD_ETHER:
2307 	case ARPHRD_FDDI:
2308 		return addrconf_ifid_eui48(eui, dev);
2309 	case ARPHRD_ARCNET:
2310 		return addrconf_ifid_arcnet(eui, dev);
2311 	case ARPHRD_INFINIBAND:
2312 		return addrconf_ifid_infiniband(eui, dev);
2313 	case ARPHRD_SIT:
2314 		return addrconf_ifid_sit(eui, dev);
2315 	case ARPHRD_IPGRE:
2316 	case ARPHRD_TUNNEL:
2317 		return addrconf_ifid_gre(eui, dev);
2318 	case ARPHRD_6LOWPAN:
2319 		return addrconf_ifid_6lowpan(eui, dev);
2320 	case ARPHRD_IEEE1394:
2321 		return addrconf_ifid_ieee1394(eui, dev);
2322 	case ARPHRD_TUNNEL6:
2323 	case ARPHRD_IP6GRE:
2324 	case ARPHRD_RAWIP:
2325 		return addrconf_ifid_ip6tnl(eui, dev);
2326 	}
2327 	return -1;
2328 }
2329 
2330 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2331 {
2332 	int err = -1;
2333 	struct inet6_ifaddr *ifp;
2334 
2335 	read_lock_bh(&idev->lock);
2336 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2337 		if (ifp->scope > IFA_LINK)
2338 			break;
2339 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2340 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2341 			err = 0;
2342 			break;
2343 		}
2344 	}
2345 	read_unlock_bh(&idev->lock);
2346 	return err;
2347 }
2348 
2349 /* Generation of a randomized Interface Identifier
2350  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2351  */
2352 
2353 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2354 {
2355 regen:
2356 	get_random_bytes(&addr->s6_addr[8], 8);
2357 
2358 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2359 	 * check if generated address is not inappropriate:
2360 	 *
2361 	 * - Reserved IPv6 Interface Identifers
2362 	 * - XXX: already assigned to an address on the device
2363 	 */
2364 
2365 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2366 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2367 		goto regen;
2368 
2369 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2370 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2371 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2372 	 */
2373 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2374 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2375 		goto regen;
2376 
2377 	/* Reserved subnet anycast addresses */
2378 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2379 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2380 		goto regen;
2381 }
2382 
2383 /*
2384  *	Add prefix route.
2385  */
2386 
2387 static void
2388 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2389 		      struct net_device *dev, unsigned long expires,
2390 		      u32 flags, gfp_t gfp_flags)
2391 {
2392 	struct fib6_config cfg = {
2393 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2394 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2395 		.fc_ifindex = dev->ifindex,
2396 		.fc_expires = expires,
2397 		.fc_dst_len = plen,
2398 		.fc_flags = RTF_UP | flags,
2399 		.fc_nlinfo.nl_net = dev_net(dev),
2400 		.fc_protocol = RTPROT_KERNEL,
2401 		.fc_type = RTN_UNICAST,
2402 	};
2403 
2404 	cfg.fc_dst = *pfx;
2405 
2406 	/* Prevent useless cloning on PtP SIT.
2407 	   This thing is done here expecting that the whole
2408 	   class of non-broadcast devices need not cloning.
2409 	 */
2410 #if IS_ENABLED(CONFIG_IPV6_SIT)
2411 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2412 		cfg.fc_flags |= RTF_NONEXTHOP;
2413 #endif
2414 
2415 	ip6_route_add(&cfg, gfp_flags, NULL);
2416 }
2417 
2418 
2419 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2420 						  int plen,
2421 						  const struct net_device *dev,
2422 						  u32 flags, u32 noflags,
2423 						  bool no_gw)
2424 {
2425 	struct fib6_node *fn;
2426 	struct fib6_info *rt = NULL;
2427 	struct fib6_table *table;
2428 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2429 
2430 	table = fib6_get_table(dev_net(dev), tb_id);
2431 	if (!table)
2432 		return NULL;
2433 
2434 	rcu_read_lock();
2435 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2436 	if (!fn)
2437 		goto out;
2438 
2439 	for_each_fib6_node_rt_rcu(fn) {
2440 		/* prefix routes only use builtin fib6_nh */
2441 		if (rt->nh)
2442 			continue;
2443 
2444 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2445 			continue;
2446 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2447 			continue;
2448 		if ((rt->fib6_flags & flags) != flags)
2449 			continue;
2450 		if ((rt->fib6_flags & noflags) != 0)
2451 			continue;
2452 		if (!fib6_info_hold_safe(rt))
2453 			continue;
2454 		break;
2455 	}
2456 out:
2457 	rcu_read_unlock();
2458 	return rt;
2459 }
2460 
2461 
2462 /* Create "default" multicast route to the interface */
2463 
2464 static void addrconf_add_mroute(struct net_device *dev)
2465 {
2466 	struct fib6_config cfg = {
2467 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2468 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2469 		.fc_ifindex = dev->ifindex,
2470 		.fc_dst_len = 8,
2471 		.fc_flags = RTF_UP,
2472 		.fc_type = RTN_MULTICAST,
2473 		.fc_nlinfo.nl_net = dev_net(dev),
2474 		.fc_protocol = RTPROT_KERNEL,
2475 	};
2476 
2477 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2478 
2479 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2480 }
2481 
2482 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2483 {
2484 	struct inet6_dev *idev;
2485 
2486 	ASSERT_RTNL();
2487 
2488 	idev = ipv6_find_idev(dev);
2489 	if (IS_ERR(idev))
2490 		return idev;
2491 
2492 	if (idev->cnf.disable_ipv6)
2493 		return ERR_PTR(-EACCES);
2494 
2495 	/* Add default multicast route */
2496 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2497 		addrconf_add_mroute(dev);
2498 
2499 	return idev;
2500 }
2501 
2502 static void manage_tempaddrs(struct inet6_dev *idev,
2503 			     struct inet6_ifaddr *ifp,
2504 			     __u32 valid_lft, __u32 prefered_lft,
2505 			     bool create, unsigned long now)
2506 {
2507 	u32 flags;
2508 	struct inet6_ifaddr *ift;
2509 
2510 	read_lock_bh(&idev->lock);
2511 	/* update all temporary addresses in the list */
2512 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2513 		int age, max_valid, max_prefered;
2514 
2515 		if (ifp != ift->ifpub)
2516 			continue;
2517 
2518 		/* RFC 4941 section 3.3:
2519 		 * If a received option will extend the lifetime of a public
2520 		 * address, the lifetimes of temporary addresses should
2521 		 * be extended, subject to the overall constraint that no
2522 		 * temporary addresses should ever remain "valid" or "preferred"
2523 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2524 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2525 		 */
2526 		age = (now - ift->cstamp) / HZ;
2527 		max_valid = idev->cnf.temp_valid_lft - age;
2528 		if (max_valid < 0)
2529 			max_valid = 0;
2530 
2531 		max_prefered = idev->cnf.temp_prefered_lft -
2532 			       idev->desync_factor - age;
2533 		if (max_prefered < 0)
2534 			max_prefered = 0;
2535 
2536 		if (valid_lft > max_valid)
2537 			valid_lft = max_valid;
2538 
2539 		if (prefered_lft > max_prefered)
2540 			prefered_lft = max_prefered;
2541 
2542 		spin_lock(&ift->lock);
2543 		flags = ift->flags;
2544 		ift->valid_lft = valid_lft;
2545 		ift->prefered_lft = prefered_lft;
2546 		ift->tstamp = now;
2547 		if (prefered_lft > 0)
2548 			ift->flags &= ~IFA_F_DEPRECATED;
2549 
2550 		spin_unlock(&ift->lock);
2551 		if (!(flags&IFA_F_TENTATIVE))
2552 			ipv6_ifa_notify(0, ift);
2553 	}
2554 
2555 	if ((create || list_empty(&idev->tempaddr_list)) &&
2556 	    idev->cnf.use_tempaddr > 0) {
2557 		/* When a new public address is created as described
2558 		 * in [ADDRCONF], also create a new temporary address.
2559 		 * Also create a temporary address if it's enabled but
2560 		 * no temporary address currently exists.
2561 		 */
2562 		read_unlock_bh(&idev->lock);
2563 		ipv6_create_tempaddr(ifp, false);
2564 	} else {
2565 		read_unlock_bh(&idev->lock);
2566 	}
2567 }
2568 
2569 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2570 {
2571 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2572 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2573 }
2574 
2575 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2576 				 const struct prefix_info *pinfo,
2577 				 struct inet6_dev *in6_dev,
2578 				 const struct in6_addr *addr, int addr_type,
2579 				 u32 addr_flags, bool sllao, bool tokenized,
2580 				 __u32 valid_lft, u32 prefered_lft)
2581 {
2582 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2583 	int create = 0;
2584 
2585 	if (!ifp && valid_lft) {
2586 		int max_addresses = in6_dev->cnf.max_addresses;
2587 		struct ifa6_config cfg = {
2588 			.pfx = addr,
2589 			.plen = pinfo->prefix_len,
2590 			.ifa_flags = addr_flags,
2591 			.valid_lft = valid_lft,
2592 			.preferred_lft = prefered_lft,
2593 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2594 		};
2595 
2596 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2597 		if ((net->ipv6.devconf_all->optimistic_dad ||
2598 		     in6_dev->cnf.optimistic_dad) &&
2599 		    !net->ipv6.devconf_all->forwarding && sllao)
2600 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2601 #endif
2602 
2603 		/* Do not allow to create too much of autoconfigured
2604 		 * addresses; this would be too easy way to crash kernel.
2605 		 */
2606 		if (!max_addresses ||
2607 		    ipv6_count_addresses(in6_dev) < max_addresses)
2608 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2609 
2610 		if (IS_ERR_OR_NULL(ifp))
2611 			return -1;
2612 
2613 		create = 1;
2614 		spin_lock_bh(&ifp->lock);
2615 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2616 		ifp->cstamp = jiffies;
2617 		ifp->tokenized = tokenized;
2618 		spin_unlock_bh(&ifp->lock);
2619 		addrconf_dad_start(ifp);
2620 	}
2621 
2622 	if (ifp) {
2623 		u32 flags;
2624 		unsigned long now;
2625 		u32 stored_lft;
2626 
2627 		/* Update lifetime (RFC4862 5.5.3 e)
2628 		 * We deviate from RFC4862 by honoring all Valid Lifetimes to
2629 		 * improve the reaction of SLAAC to renumbering events
2630 		 * (draft-gont-6man-slaac-renum-06, Section 4.2)
2631 		 */
2632 		spin_lock_bh(&ifp->lock);
2633 		now = jiffies;
2634 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2635 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2636 		else
2637 			stored_lft = 0;
2638 
2639 		if (!create && stored_lft) {
2640 			ifp->valid_lft = valid_lft;
2641 			ifp->prefered_lft = prefered_lft;
2642 			ifp->tstamp = now;
2643 			flags = ifp->flags;
2644 			ifp->flags &= ~IFA_F_DEPRECATED;
2645 			spin_unlock_bh(&ifp->lock);
2646 
2647 			if (!(flags&IFA_F_TENTATIVE))
2648 				ipv6_ifa_notify(0, ifp);
2649 		} else
2650 			spin_unlock_bh(&ifp->lock);
2651 
2652 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2653 				 create, now);
2654 
2655 		in6_ifa_put(ifp);
2656 		addrconf_verify();
2657 	}
2658 
2659 	return 0;
2660 }
2661 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2662 
2663 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2664 {
2665 	struct prefix_info *pinfo;
2666 	__u32 valid_lft;
2667 	__u32 prefered_lft;
2668 	int addr_type, err;
2669 	u32 addr_flags = 0;
2670 	struct inet6_dev *in6_dev;
2671 	struct net *net = dev_net(dev);
2672 
2673 	pinfo = (struct prefix_info *) opt;
2674 
2675 	if (len < sizeof(struct prefix_info)) {
2676 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2677 		return;
2678 	}
2679 
2680 	/*
2681 	 *	Validation checks ([ADDRCONF], page 19)
2682 	 */
2683 
2684 	addr_type = ipv6_addr_type(&pinfo->prefix);
2685 
2686 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2687 		return;
2688 
2689 	valid_lft = ntohl(pinfo->valid);
2690 	prefered_lft = ntohl(pinfo->prefered);
2691 
2692 	if (prefered_lft > valid_lft) {
2693 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2694 		return;
2695 	}
2696 
2697 	in6_dev = in6_dev_get(dev);
2698 
2699 	if (!in6_dev) {
2700 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2701 				    dev->name);
2702 		return;
2703 	}
2704 
2705 	/*
2706 	 *	Two things going on here:
2707 	 *	1) Add routes for on-link prefixes
2708 	 *	2) Configure prefixes with the auto flag set
2709 	 */
2710 
2711 	if (pinfo->onlink) {
2712 		struct fib6_info *rt;
2713 		unsigned long rt_expires;
2714 
2715 		/* Avoid arithmetic overflow. Really, we could
2716 		 * save rt_expires in seconds, likely valid_lft,
2717 		 * but it would require division in fib gc, that it
2718 		 * not good.
2719 		 */
2720 		if (HZ > USER_HZ)
2721 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2722 		else
2723 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2724 
2725 		if (addrconf_finite_timeout(rt_expires))
2726 			rt_expires *= HZ;
2727 
2728 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2729 					       pinfo->prefix_len,
2730 					       dev,
2731 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2732 					       RTF_DEFAULT, true);
2733 
2734 		if (rt) {
2735 			/* Autoconf prefix route */
2736 			if (valid_lft == 0) {
2737 				ip6_del_rt(net, rt, false);
2738 				rt = NULL;
2739 			} else if (addrconf_finite_timeout(rt_expires)) {
2740 				/* not infinity */
2741 				fib6_set_expires(rt, jiffies + rt_expires);
2742 			} else {
2743 				fib6_clean_expires(rt);
2744 			}
2745 		} else if (valid_lft) {
2746 			clock_t expires = 0;
2747 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2748 			if (addrconf_finite_timeout(rt_expires)) {
2749 				/* not infinity */
2750 				flags |= RTF_EXPIRES;
2751 				expires = jiffies_to_clock_t(rt_expires);
2752 			}
2753 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2754 					      0, dev, expires, flags,
2755 					      GFP_ATOMIC);
2756 		}
2757 		fib6_info_release(rt);
2758 	}
2759 
2760 	/* Try to figure out our local address for this prefix */
2761 
2762 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2763 		struct in6_addr addr;
2764 		bool tokenized = false, dev_addr_generated = false;
2765 
2766 		if (pinfo->prefix_len == 64) {
2767 			memcpy(&addr, &pinfo->prefix, 8);
2768 
2769 			if (!ipv6_addr_any(&in6_dev->token)) {
2770 				read_lock_bh(&in6_dev->lock);
2771 				memcpy(addr.s6_addr + 8,
2772 				       in6_dev->token.s6_addr + 8, 8);
2773 				read_unlock_bh(&in6_dev->lock);
2774 				tokenized = true;
2775 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2776 				   !ipv6_generate_stable_address(&addr, 0,
2777 								 in6_dev)) {
2778 				addr_flags |= IFA_F_STABLE_PRIVACY;
2779 				goto ok;
2780 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2781 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2782 				goto put;
2783 			} else {
2784 				dev_addr_generated = true;
2785 			}
2786 			goto ok;
2787 		}
2788 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2789 				    pinfo->prefix_len);
2790 		goto put;
2791 
2792 ok:
2793 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2794 						   &addr, addr_type,
2795 						   addr_flags, sllao,
2796 						   tokenized, valid_lft,
2797 						   prefered_lft);
2798 		if (err)
2799 			goto put;
2800 
2801 		/* Ignore error case here because previous prefix add addr was
2802 		 * successful which will be notified.
2803 		 */
2804 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2805 					      addr_type, addr_flags, sllao,
2806 					      tokenized, valid_lft,
2807 					      prefered_lft,
2808 					      dev_addr_generated);
2809 	}
2810 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2811 put:
2812 	in6_dev_put(in6_dev);
2813 }
2814 
2815 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2816 		struct in6_ifreq *ireq)
2817 {
2818 	struct ip_tunnel_parm p = { };
2819 	int err;
2820 
2821 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2822 		return -EADDRNOTAVAIL;
2823 
2824 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2825 	p.iph.version = 4;
2826 	p.iph.ihl = 5;
2827 	p.iph.protocol = IPPROTO_IPV6;
2828 	p.iph.ttl = 64;
2829 
2830 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2831 		return -EOPNOTSUPP;
2832 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2833 	if (err)
2834 		return err;
2835 
2836 	dev = __dev_get_by_name(net, p.name);
2837 	if (!dev)
2838 		return -ENOBUFS;
2839 	return dev_open(dev, NULL);
2840 }
2841 
2842 /*
2843  *	Set destination address.
2844  *	Special case for SIT interfaces where we create a new "virtual"
2845  *	device.
2846  */
2847 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2848 {
2849 	struct net_device *dev;
2850 	struct in6_ifreq ireq;
2851 	int err = -ENODEV;
2852 
2853 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2854 		return -ENODEV;
2855 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2856 		return -EFAULT;
2857 
2858 	rtnl_lock();
2859 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2860 	if (dev && dev->type == ARPHRD_SIT)
2861 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2862 	rtnl_unlock();
2863 	return err;
2864 }
2865 
2866 static int ipv6_mc_config(struct sock *sk, bool join,
2867 			  const struct in6_addr *addr, int ifindex)
2868 {
2869 	int ret;
2870 
2871 	ASSERT_RTNL();
2872 
2873 	lock_sock(sk);
2874 	if (join)
2875 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2876 	else
2877 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2878 	release_sock(sk);
2879 
2880 	return ret;
2881 }
2882 
2883 /*
2884  *	Manual configuration of address on an interface
2885  */
2886 static int inet6_addr_add(struct net *net, int ifindex,
2887 			  struct ifa6_config *cfg,
2888 			  struct netlink_ext_ack *extack)
2889 {
2890 	struct inet6_ifaddr *ifp;
2891 	struct inet6_dev *idev;
2892 	struct net_device *dev;
2893 	unsigned long timeout;
2894 	clock_t expires;
2895 	u32 flags;
2896 
2897 	ASSERT_RTNL();
2898 
2899 	if (cfg->plen > 128)
2900 		return -EINVAL;
2901 
2902 	/* check the lifetime */
2903 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2904 		return -EINVAL;
2905 
2906 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2907 		return -EINVAL;
2908 
2909 	dev = __dev_get_by_index(net, ifindex);
2910 	if (!dev)
2911 		return -ENODEV;
2912 
2913 	idev = addrconf_add_dev(dev);
2914 	if (IS_ERR(idev))
2915 		return PTR_ERR(idev);
2916 
2917 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2918 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2919 					 true, cfg->pfx, ifindex);
2920 
2921 		if (ret < 0)
2922 			return ret;
2923 	}
2924 
2925 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2926 
2927 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2928 	if (addrconf_finite_timeout(timeout)) {
2929 		expires = jiffies_to_clock_t(timeout * HZ);
2930 		cfg->valid_lft = timeout;
2931 		flags = RTF_EXPIRES;
2932 	} else {
2933 		expires = 0;
2934 		flags = 0;
2935 		cfg->ifa_flags |= IFA_F_PERMANENT;
2936 	}
2937 
2938 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2939 	if (addrconf_finite_timeout(timeout)) {
2940 		if (timeout == 0)
2941 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2942 		cfg->preferred_lft = timeout;
2943 	}
2944 
2945 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2946 	if (!IS_ERR(ifp)) {
2947 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2948 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2949 					      ifp->rt_priority, dev, expires,
2950 					      flags, GFP_KERNEL);
2951 		}
2952 
2953 		/* Send a netlink notification if DAD is enabled and
2954 		 * optimistic flag is not set
2955 		 */
2956 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2957 			ipv6_ifa_notify(0, ifp);
2958 		/*
2959 		 * Note that section 3.1 of RFC 4429 indicates
2960 		 * that the Optimistic flag should not be set for
2961 		 * manually configured addresses
2962 		 */
2963 		addrconf_dad_start(ifp);
2964 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2965 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2966 					 cfg->preferred_lft, true, jiffies);
2967 		in6_ifa_put(ifp);
2968 		addrconf_verify_rtnl();
2969 		return 0;
2970 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2971 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2972 			       cfg->pfx, ifindex);
2973 	}
2974 
2975 	return PTR_ERR(ifp);
2976 }
2977 
2978 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2979 			  const struct in6_addr *pfx, unsigned int plen)
2980 {
2981 	struct inet6_ifaddr *ifp;
2982 	struct inet6_dev *idev;
2983 	struct net_device *dev;
2984 
2985 	if (plen > 128)
2986 		return -EINVAL;
2987 
2988 	dev = __dev_get_by_index(net, ifindex);
2989 	if (!dev)
2990 		return -ENODEV;
2991 
2992 	idev = __in6_dev_get(dev);
2993 	if (!idev)
2994 		return -ENXIO;
2995 
2996 	read_lock_bh(&idev->lock);
2997 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2998 		if (ifp->prefix_len == plen &&
2999 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3000 			in6_ifa_hold(ifp);
3001 			read_unlock_bh(&idev->lock);
3002 
3003 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3004 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3005 				manage_tempaddrs(idev, ifp, 0, 0, false,
3006 						 jiffies);
3007 			ipv6_del_addr(ifp);
3008 			addrconf_verify_rtnl();
3009 			if (ipv6_addr_is_multicast(pfx)) {
3010 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3011 					       false, pfx, dev->ifindex);
3012 			}
3013 			return 0;
3014 		}
3015 	}
3016 	read_unlock_bh(&idev->lock);
3017 	return -EADDRNOTAVAIL;
3018 }
3019 
3020 
3021 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3022 {
3023 	struct ifa6_config cfg = {
3024 		.ifa_flags = IFA_F_PERMANENT,
3025 		.preferred_lft = INFINITY_LIFE_TIME,
3026 		.valid_lft = INFINITY_LIFE_TIME,
3027 	};
3028 	struct in6_ifreq ireq;
3029 	int err;
3030 
3031 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3032 		return -EPERM;
3033 
3034 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3035 		return -EFAULT;
3036 
3037 	cfg.pfx = &ireq.ifr6_addr;
3038 	cfg.plen = ireq.ifr6_prefixlen;
3039 
3040 	rtnl_lock();
3041 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3042 	rtnl_unlock();
3043 	return err;
3044 }
3045 
3046 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3047 {
3048 	struct in6_ifreq ireq;
3049 	int err;
3050 
3051 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3052 		return -EPERM;
3053 
3054 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3055 		return -EFAULT;
3056 
3057 	rtnl_lock();
3058 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3059 			     ireq.ifr6_prefixlen);
3060 	rtnl_unlock();
3061 	return err;
3062 }
3063 
3064 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3065 		     int plen, int scope)
3066 {
3067 	struct inet6_ifaddr *ifp;
3068 	struct ifa6_config cfg = {
3069 		.pfx = addr,
3070 		.plen = plen,
3071 		.ifa_flags = IFA_F_PERMANENT,
3072 		.valid_lft = INFINITY_LIFE_TIME,
3073 		.preferred_lft = INFINITY_LIFE_TIME,
3074 		.scope = scope
3075 	};
3076 
3077 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3078 	if (!IS_ERR(ifp)) {
3079 		spin_lock_bh(&ifp->lock);
3080 		ifp->flags &= ~IFA_F_TENTATIVE;
3081 		spin_unlock_bh(&ifp->lock);
3082 		rt_genid_bump_ipv6(dev_net(idev->dev));
3083 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3084 		in6_ifa_put(ifp);
3085 	}
3086 }
3087 
3088 #if IS_ENABLED(CONFIG_IPV6_SIT)
3089 static void sit_add_v4_addrs(struct inet6_dev *idev)
3090 {
3091 	struct in6_addr addr;
3092 	struct net_device *dev;
3093 	struct net *net = dev_net(idev->dev);
3094 	int scope, plen;
3095 	u32 pflags = 0;
3096 
3097 	ASSERT_RTNL();
3098 
3099 	memset(&addr, 0, sizeof(struct in6_addr));
3100 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3101 
3102 	if (idev->dev->flags&IFF_POINTOPOINT) {
3103 		addr.s6_addr32[0] = htonl(0xfe800000);
3104 		scope = IFA_LINK;
3105 		plen = 64;
3106 	} else {
3107 		scope = IPV6_ADDR_COMPATv4;
3108 		plen = 96;
3109 		pflags |= RTF_NONEXTHOP;
3110 	}
3111 
3112 	if (addr.s6_addr32[3]) {
3113 		add_addr(idev, &addr, plen, scope);
3114 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3115 				      GFP_KERNEL);
3116 		return;
3117 	}
3118 
3119 	for_each_netdev(net, dev) {
3120 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3121 		if (in_dev && (dev->flags & IFF_UP)) {
3122 			struct in_ifaddr *ifa;
3123 			int flag = scope;
3124 
3125 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3126 				addr.s6_addr32[3] = ifa->ifa_local;
3127 
3128 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3129 					continue;
3130 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3131 					if (idev->dev->flags&IFF_POINTOPOINT)
3132 						continue;
3133 					flag |= IFA_HOST;
3134 				}
3135 
3136 				add_addr(idev, &addr, plen, flag);
3137 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3138 						      0, pflags, GFP_KERNEL);
3139 			}
3140 		}
3141 	}
3142 }
3143 #endif
3144 
3145 static void init_loopback(struct net_device *dev)
3146 {
3147 	struct inet6_dev  *idev;
3148 
3149 	/* ::1 */
3150 
3151 	ASSERT_RTNL();
3152 
3153 	idev = ipv6_find_idev(dev);
3154 	if (IS_ERR(idev)) {
3155 		pr_debug("%s: add_dev failed\n", __func__);
3156 		return;
3157 	}
3158 
3159 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3160 }
3161 
3162 void addrconf_add_linklocal(struct inet6_dev *idev,
3163 			    const struct in6_addr *addr, u32 flags)
3164 {
3165 	struct ifa6_config cfg = {
3166 		.pfx = addr,
3167 		.plen = 64,
3168 		.ifa_flags = flags | IFA_F_PERMANENT,
3169 		.valid_lft = INFINITY_LIFE_TIME,
3170 		.preferred_lft = INFINITY_LIFE_TIME,
3171 		.scope = IFA_LINK
3172 	};
3173 	struct inet6_ifaddr *ifp;
3174 
3175 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3176 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3177 	     idev->cnf.optimistic_dad) &&
3178 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3179 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3180 #endif
3181 
3182 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3183 	if (!IS_ERR(ifp)) {
3184 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3185 				      0, 0, GFP_ATOMIC);
3186 		addrconf_dad_start(ifp);
3187 		in6_ifa_put(ifp);
3188 	}
3189 }
3190 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3191 
3192 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3193 {
3194 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3195 		return true;
3196 
3197 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3198 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3199 		return true;
3200 
3201 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3202 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3203 		return true;
3204 
3205 	return false;
3206 }
3207 
3208 static int ipv6_generate_stable_address(struct in6_addr *address,
3209 					u8 dad_count,
3210 					const struct inet6_dev *idev)
3211 {
3212 	static DEFINE_SPINLOCK(lock);
3213 	static __u32 digest[SHA1_DIGEST_WORDS];
3214 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3215 
3216 	static union {
3217 		char __data[SHA1_BLOCK_SIZE];
3218 		struct {
3219 			struct in6_addr secret;
3220 			__be32 prefix[2];
3221 			unsigned char hwaddr[MAX_ADDR_LEN];
3222 			u8 dad_count;
3223 		} __packed;
3224 	} data;
3225 
3226 	struct in6_addr secret;
3227 	struct in6_addr temp;
3228 	struct net *net = dev_net(idev->dev);
3229 
3230 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3231 
3232 	if (idev->cnf.stable_secret.initialized)
3233 		secret = idev->cnf.stable_secret.secret;
3234 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3235 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3236 	else
3237 		return -1;
3238 
3239 retry:
3240 	spin_lock_bh(&lock);
3241 
3242 	sha1_init(digest);
3243 	memset(&data, 0, sizeof(data));
3244 	memset(workspace, 0, sizeof(workspace));
3245 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3246 	data.prefix[0] = address->s6_addr32[0];
3247 	data.prefix[1] = address->s6_addr32[1];
3248 	data.secret = secret;
3249 	data.dad_count = dad_count;
3250 
3251 	sha1_transform(digest, data.__data, workspace);
3252 
3253 	temp = *address;
3254 	temp.s6_addr32[2] = (__force __be32)digest[0];
3255 	temp.s6_addr32[3] = (__force __be32)digest[1];
3256 
3257 	spin_unlock_bh(&lock);
3258 
3259 	if (ipv6_reserved_interfaceid(temp)) {
3260 		dad_count++;
3261 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3262 			return -1;
3263 		goto retry;
3264 	}
3265 
3266 	*address = temp;
3267 	return 0;
3268 }
3269 
3270 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3271 {
3272 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3273 
3274 	if (s->initialized)
3275 		return;
3276 	s = &idev->cnf.stable_secret;
3277 	get_random_bytes(&s->secret, sizeof(s->secret));
3278 	s->initialized = true;
3279 }
3280 
3281 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3282 {
3283 	struct in6_addr addr;
3284 
3285 	/* no link local addresses on L3 master devices */
3286 	if (netif_is_l3_master(idev->dev))
3287 		return;
3288 
3289 	/* no link local addresses on devices flagged as slaves */
3290 	if (idev->dev->flags & IFF_SLAVE)
3291 		return;
3292 
3293 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3294 
3295 	switch (idev->cnf.addr_gen_mode) {
3296 	case IN6_ADDR_GEN_MODE_RANDOM:
3297 		ipv6_gen_mode_random_init(idev);
3298 		fallthrough;
3299 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3300 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3301 			addrconf_add_linklocal(idev, &addr,
3302 					       IFA_F_STABLE_PRIVACY);
3303 		else if (prefix_route)
3304 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3305 					      0, 0, GFP_KERNEL);
3306 		break;
3307 	case IN6_ADDR_GEN_MODE_EUI64:
3308 		/* addrconf_add_linklocal also adds a prefix_route and we
3309 		 * only need to care about prefix routes if ipv6_generate_eui64
3310 		 * couldn't generate one.
3311 		 */
3312 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3313 			addrconf_add_linklocal(idev, &addr, 0);
3314 		else if (prefix_route)
3315 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3316 					      0, 0, GFP_KERNEL);
3317 		break;
3318 	case IN6_ADDR_GEN_MODE_NONE:
3319 	default:
3320 		/* will not add any link local address */
3321 		break;
3322 	}
3323 }
3324 
3325 static void addrconf_dev_config(struct net_device *dev)
3326 {
3327 	struct inet6_dev *idev;
3328 
3329 	ASSERT_RTNL();
3330 
3331 	if ((dev->type != ARPHRD_ETHER) &&
3332 	    (dev->type != ARPHRD_FDDI) &&
3333 	    (dev->type != ARPHRD_ARCNET) &&
3334 	    (dev->type != ARPHRD_INFINIBAND) &&
3335 	    (dev->type != ARPHRD_IEEE1394) &&
3336 	    (dev->type != ARPHRD_TUNNEL6) &&
3337 	    (dev->type != ARPHRD_6LOWPAN) &&
3338 	    (dev->type != ARPHRD_IP6GRE) &&
3339 	    (dev->type != ARPHRD_IPGRE) &&
3340 	    (dev->type != ARPHRD_TUNNEL) &&
3341 	    (dev->type != ARPHRD_NONE) &&
3342 	    (dev->type != ARPHRD_RAWIP)) {
3343 		/* Alas, we support only Ethernet autoconfiguration. */
3344 		idev = __in6_dev_get(dev);
3345 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3346 		    dev->flags & IFF_MULTICAST)
3347 			ipv6_mc_up(idev);
3348 		return;
3349 	}
3350 
3351 	idev = addrconf_add_dev(dev);
3352 	if (IS_ERR(idev))
3353 		return;
3354 
3355 	/* this device type has no EUI support */
3356 	if (dev->type == ARPHRD_NONE &&
3357 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3358 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3359 
3360 	addrconf_addr_gen(idev, false);
3361 }
3362 
3363 #if IS_ENABLED(CONFIG_IPV6_SIT)
3364 static void addrconf_sit_config(struct net_device *dev)
3365 {
3366 	struct inet6_dev *idev;
3367 
3368 	ASSERT_RTNL();
3369 
3370 	/*
3371 	 * Configure the tunnel with one of our IPv4
3372 	 * addresses... we should configure all of
3373 	 * our v4 addrs in the tunnel
3374 	 */
3375 
3376 	idev = ipv6_find_idev(dev);
3377 	if (IS_ERR(idev)) {
3378 		pr_debug("%s: add_dev failed\n", __func__);
3379 		return;
3380 	}
3381 
3382 	if (dev->priv_flags & IFF_ISATAP) {
3383 		addrconf_addr_gen(idev, false);
3384 		return;
3385 	}
3386 
3387 	sit_add_v4_addrs(idev);
3388 
3389 	if (dev->flags&IFF_POINTOPOINT)
3390 		addrconf_add_mroute(dev);
3391 }
3392 #endif
3393 
3394 #if IS_ENABLED(CONFIG_NET_IPGRE)
3395 static void addrconf_gre_config(struct net_device *dev)
3396 {
3397 	struct inet6_dev *idev;
3398 
3399 	ASSERT_RTNL();
3400 
3401 	idev = ipv6_find_idev(dev);
3402 	if (IS_ERR(idev)) {
3403 		pr_debug("%s: add_dev failed\n", __func__);
3404 		return;
3405 	}
3406 
3407 	addrconf_addr_gen(idev, true);
3408 	if (dev->flags & IFF_POINTOPOINT)
3409 		addrconf_add_mroute(dev);
3410 }
3411 #endif
3412 
3413 static int fixup_permanent_addr(struct net *net,
3414 				struct inet6_dev *idev,
3415 				struct inet6_ifaddr *ifp)
3416 {
3417 	/* !fib6_node means the host route was removed from the
3418 	 * FIB, for example, if 'lo' device is taken down. In that
3419 	 * case regenerate the host route.
3420 	 */
3421 	if (!ifp->rt || !ifp->rt->fib6_node) {
3422 		struct fib6_info *f6i, *prev;
3423 
3424 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3425 					 GFP_ATOMIC);
3426 		if (IS_ERR(f6i))
3427 			return PTR_ERR(f6i);
3428 
3429 		/* ifp->rt can be accessed outside of rtnl */
3430 		spin_lock(&ifp->lock);
3431 		prev = ifp->rt;
3432 		ifp->rt = f6i;
3433 		spin_unlock(&ifp->lock);
3434 
3435 		fib6_info_release(prev);
3436 	}
3437 
3438 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3439 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3440 				      ifp->rt_priority, idev->dev, 0, 0,
3441 				      GFP_ATOMIC);
3442 	}
3443 
3444 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3445 		addrconf_dad_start(ifp);
3446 
3447 	return 0;
3448 }
3449 
3450 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3451 {
3452 	struct inet6_ifaddr *ifp, *tmp;
3453 	struct inet6_dev *idev;
3454 
3455 	idev = __in6_dev_get(dev);
3456 	if (!idev)
3457 		return;
3458 
3459 	write_lock_bh(&idev->lock);
3460 
3461 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3462 		if ((ifp->flags & IFA_F_PERMANENT) &&
3463 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3464 			write_unlock_bh(&idev->lock);
3465 			in6_ifa_hold(ifp);
3466 			ipv6_del_addr(ifp);
3467 			write_lock_bh(&idev->lock);
3468 
3469 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3470 					     idev->dev->name, &ifp->addr);
3471 		}
3472 	}
3473 
3474 	write_unlock_bh(&idev->lock);
3475 }
3476 
3477 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3478 			   void *ptr)
3479 {
3480 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3481 	struct netdev_notifier_change_info *change_info;
3482 	struct netdev_notifier_changeupper_info *info;
3483 	struct inet6_dev *idev = __in6_dev_get(dev);
3484 	struct net *net = dev_net(dev);
3485 	int run_pending = 0;
3486 	int err;
3487 
3488 	switch (event) {
3489 	case NETDEV_REGISTER:
3490 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3491 			idev = ipv6_add_dev(dev);
3492 			if (IS_ERR(idev))
3493 				return notifier_from_errno(PTR_ERR(idev));
3494 		}
3495 		break;
3496 
3497 	case NETDEV_CHANGEMTU:
3498 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3499 		if (dev->mtu < IPV6_MIN_MTU) {
3500 			addrconf_ifdown(dev, dev != net->loopback_dev);
3501 			break;
3502 		}
3503 
3504 		if (idev) {
3505 			rt6_mtu_change(dev, dev->mtu);
3506 			idev->cnf.mtu6 = dev->mtu;
3507 			break;
3508 		}
3509 
3510 		/* allocate new idev */
3511 		idev = ipv6_add_dev(dev);
3512 		if (IS_ERR(idev))
3513 			break;
3514 
3515 		/* device is still not ready */
3516 		if (!(idev->if_flags & IF_READY))
3517 			break;
3518 
3519 		run_pending = 1;
3520 		fallthrough;
3521 	case NETDEV_UP:
3522 	case NETDEV_CHANGE:
3523 		if (dev->flags & IFF_SLAVE)
3524 			break;
3525 
3526 		if (idev && idev->cnf.disable_ipv6)
3527 			break;
3528 
3529 		if (event == NETDEV_UP) {
3530 			/* restore routes for permanent addresses */
3531 			addrconf_permanent_addr(net, dev);
3532 
3533 			if (!addrconf_link_ready(dev)) {
3534 				/* device is not ready yet. */
3535 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3536 					 dev->name);
3537 				break;
3538 			}
3539 
3540 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3541 				idev = ipv6_add_dev(dev);
3542 
3543 			if (!IS_ERR_OR_NULL(idev)) {
3544 				idev->if_flags |= IF_READY;
3545 				run_pending = 1;
3546 			}
3547 		} else if (event == NETDEV_CHANGE) {
3548 			if (!addrconf_link_ready(dev)) {
3549 				/* device is still not ready. */
3550 				rt6_sync_down_dev(dev, event);
3551 				break;
3552 			}
3553 
3554 			if (!IS_ERR_OR_NULL(idev)) {
3555 				if (idev->if_flags & IF_READY) {
3556 					/* device is already configured -
3557 					 * but resend MLD reports, we might
3558 					 * have roamed and need to update
3559 					 * multicast snooping switches
3560 					 */
3561 					ipv6_mc_up(idev);
3562 					change_info = ptr;
3563 					if (change_info->flags_changed & IFF_NOARP)
3564 						addrconf_dad_run(idev, true);
3565 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3566 					break;
3567 				}
3568 				idev->if_flags |= IF_READY;
3569 			}
3570 
3571 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3572 				dev->name);
3573 
3574 			run_pending = 1;
3575 		}
3576 
3577 		switch (dev->type) {
3578 #if IS_ENABLED(CONFIG_IPV6_SIT)
3579 		case ARPHRD_SIT:
3580 			addrconf_sit_config(dev);
3581 			break;
3582 #endif
3583 #if IS_ENABLED(CONFIG_NET_IPGRE)
3584 		case ARPHRD_IPGRE:
3585 			addrconf_gre_config(dev);
3586 			break;
3587 #endif
3588 		case ARPHRD_LOOPBACK:
3589 			init_loopback(dev);
3590 			break;
3591 
3592 		default:
3593 			addrconf_dev_config(dev);
3594 			break;
3595 		}
3596 
3597 		if (!IS_ERR_OR_NULL(idev)) {
3598 			if (run_pending)
3599 				addrconf_dad_run(idev, false);
3600 
3601 			/* Device has an address by now */
3602 			rt6_sync_up(dev, RTNH_F_DEAD);
3603 
3604 			/*
3605 			 * If the MTU changed during the interface down,
3606 			 * when the interface up, the changed MTU must be
3607 			 * reflected in the idev as well as routers.
3608 			 */
3609 			if (idev->cnf.mtu6 != dev->mtu &&
3610 			    dev->mtu >= IPV6_MIN_MTU) {
3611 				rt6_mtu_change(dev, dev->mtu);
3612 				idev->cnf.mtu6 = dev->mtu;
3613 			}
3614 			idev->tstamp = jiffies;
3615 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3616 
3617 			/*
3618 			 * If the changed mtu during down is lower than
3619 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3620 			 */
3621 			if (dev->mtu < IPV6_MIN_MTU)
3622 				addrconf_ifdown(dev, dev != net->loopback_dev);
3623 		}
3624 		break;
3625 
3626 	case NETDEV_DOWN:
3627 	case NETDEV_UNREGISTER:
3628 		/*
3629 		 *	Remove all addresses from this interface.
3630 		 */
3631 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3632 		break;
3633 
3634 	case NETDEV_CHANGENAME:
3635 		if (idev) {
3636 			snmp6_unregister_dev(idev);
3637 			addrconf_sysctl_unregister(idev);
3638 			err = addrconf_sysctl_register(idev);
3639 			if (err)
3640 				return notifier_from_errno(err);
3641 			err = snmp6_register_dev(idev);
3642 			if (err) {
3643 				addrconf_sysctl_unregister(idev);
3644 				return notifier_from_errno(err);
3645 			}
3646 		}
3647 		break;
3648 
3649 	case NETDEV_PRE_TYPE_CHANGE:
3650 	case NETDEV_POST_TYPE_CHANGE:
3651 		if (idev)
3652 			addrconf_type_change(dev, event);
3653 		break;
3654 
3655 	case NETDEV_CHANGEUPPER:
3656 		info = ptr;
3657 
3658 		/* flush all routes if dev is linked to or unlinked from
3659 		 * an L3 master device (e.g., VRF)
3660 		 */
3661 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3662 			addrconf_ifdown(dev, false);
3663 	}
3664 
3665 	return NOTIFY_OK;
3666 }
3667 
3668 /*
3669  *	addrconf module should be notified of a device going up
3670  */
3671 static struct notifier_block ipv6_dev_notf = {
3672 	.notifier_call = addrconf_notify,
3673 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3674 };
3675 
3676 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3677 {
3678 	struct inet6_dev *idev;
3679 	ASSERT_RTNL();
3680 
3681 	idev = __in6_dev_get(dev);
3682 
3683 	if (event == NETDEV_POST_TYPE_CHANGE)
3684 		ipv6_mc_remap(idev);
3685 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3686 		ipv6_mc_unmap(idev);
3687 }
3688 
3689 static bool addr_is_local(const struct in6_addr *addr)
3690 {
3691 	return ipv6_addr_type(addr) &
3692 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3693 }
3694 
3695 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3696 {
3697 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3698 	struct net *net = dev_net(dev);
3699 	struct inet6_dev *idev;
3700 	struct inet6_ifaddr *ifa, *tmp;
3701 	bool keep_addr = false;
3702 	int state, i;
3703 
3704 	ASSERT_RTNL();
3705 
3706 	rt6_disable_ip(dev, event);
3707 
3708 	idev = __in6_dev_get(dev);
3709 	if (!idev)
3710 		return -ENODEV;
3711 
3712 	/*
3713 	 * Step 1: remove reference to ipv6 device from parent device.
3714 	 *	   Do not dev_put!
3715 	 */
3716 	if (unregister) {
3717 		idev->dead = 1;
3718 
3719 		/* protected by rtnl_lock */
3720 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3721 
3722 		/* Step 1.5: remove snmp6 entry */
3723 		snmp6_unregister_dev(idev);
3724 
3725 	}
3726 
3727 	/* combine the user config with event to determine if permanent
3728 	 * addresses are to be removed from address hash table
3729 	 */
3730 	if (!unregister && !idev->cnf.disable_ipv6) {
3731 		/* aggregate the system setting and interface setting */
3732 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3733 
3734 		if (!_keep_addr)
3735 			_keep_addr = idev->cnf.keep_addr_on_down;
3736 
3737 		keep_addr = (_keep_addr > 0);
3738 	}
3739 
3740 	/* Step 2: clear hash table */
3741 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3742 		struct hlist_head *h = &inet6_addr_lst[i];
3743 
3744 		spin_lock_bh(&addrconf_hash_lock);
3745 restart:
3746 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3747 			if (ifa->idev == idev) {
3748 				addrconf_del_dad_work(ifa);
3749 				/* combined flag + permanent flag decide if
3750 				 * address is retained on a down event
3751 				 */
3752 				if (!keep_addr ||
3753 				    !(ifa->flags & IFA_F_PERMANENT) ||
3754 				    addr_is_local(&ifa->addr)) {
3755 					hlist_del_init_rcu(&ifa->addr_lst);
3756 					goto restart;
3757 				}
3758 			}
3759 		}
3760 		spin_unlock_bh(&addrconf_hash_lock);
3761 	}
3762 
3763 	write_lock_bh(&idev->lock);
3764 
3765 	addrconf_del_rs_timer(idev);
3766 
3767 	/* Step 2: clear flags for stateless addrconf */
3768 	if (!unregister)
3769 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3770 
3771 	/* Step 3: clear tempaddr list */
3772 	while (!list_empty(&idev->tempaddr_list)) {
3773 		ifa = list_first_entry(&idev->tempaddr_list,
3774 				       struct inet6_ifaddr, tmp_list);
3775 		list_del(&ifa->tmp_list);
3776 		write_unlock_bh(&idev->lock);
3777 		spin_lock_bh(&ifa->lock);
3778 
3779 		if (ifa->ifpub) {
3780 			in6_ifa_put(ifa->ifpub);
3781 			ifa->ifpub = NULL;
3782 		}
3783 		spin_unlock_bh(&ifa->lock);
3784 		in6_ifa_put(ifa);
3785 		write_lock_bh(&idev->lock);
3786 	}
3787 
3788 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3789 		struct fib6_info *rt = NULL;
3790 		bool keep;
3791 
3792 		addrconf_del_dad_work(ifa);
3793 
3794 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3795 			!addr_is_local(&ifa->addr);
3796 
3797 		write_unlock_bh(&idev->lock);
3798 		spin_lock_bh(&ifa->lock);
3799 
3800 		if (keep) {
3801 			/* set state to skip the notifier below */
3802 			state = INET6_IFADDR_STATE_DEAD;
3803 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3804 			if (!(ifa->flags & IFA_F_NODAD))
3805 				ifa->flags |= IFA_F_TENTATIVE;
3806 
3807 			rt = ifa->rt;
3808 			ifa->rt = NULL;
3809 		} else {
3810 			state = ifa->state;
3811 			ifa->state = INET6_IFADDR_STATE_DEAD;
3812 		}
3813 
3814 		spin_unlock_bh(&ifa->lock);
3815 
3816 		if (rt)
3817 			ip6_del_rt(net, rt, false);
3818 
3819 		if (state != INET6_IFADDR_STATE_DEAD) {
3820 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3821 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3822 		} else {
3823 			if (idev->cnf.forwarding)
3824 				addrconf_leave_anycast(ifa);
3825 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3826 		}
3827 
3828 		write_lock_bh(&idev->lock);
3829 		if (!keep) {
3830 			list_del_rcu(&ifa->if_list);
3831 			in6_ifa_put(ifa);
3832 		}
3833 	}
3834 
3835 	write_unlock_bh(&idev->lock);
3836 
3837 	/* Step 5: Discard anycast and multicast list */
3838 	if (unregister) {
3839 		ipv6_ac_destroy_dev(idev);
3840 		ipv6_mc_destroy_dev(idev);
3841 	} else {
3842 		ipv6_mc_down(idev);
3843 	}
3844 
3845 	idev->tstamp = jiffies;
3846 
3847 	/* Last: Shot the device (if unregistered) */
3848 	if (unregister) {
3849 		addrconf_sysctl_unregister(idev);
3850 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3851 		neigh_ifdown(&nd_tbl, dev);
3852 		in6_dev_put(idev);
3853 	}
3854 	return 0;
3855 }
3856 
3857 static void addrconf_rs_timer(struct timer_list *t)
3858 {
3859 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3860 	struct net_device *dev = idev->dev;
3861 	struct in6_addr lladdr;
3862 
3863 	write_lock(&idev->lock);
3864 	if (idev->dead || !(idev->if_flags & IF_READY))
3865 		goto out;
3866 
3867 	if (!ipv6_accept_ra(idev))
3868 		goto out;
3869 
3870 	/* Announcement received after solicitation was sent */
3871 	if (idev->if_flags & IF_RA_RCVD)
3872 		goto out;
3873 
3874 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3875 		write_unlock(&idev->lock);
3876 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3877 			ndisc_send_rs(dev, &lladdr,
3878 				      &in6addr_linklocal_allrouters);
3879 		else
3880 			goto put;
3881 
3882 		write_lock(&idev->lock);
3883 		idev->rs_interval = rfc3315_s14_backoff_update(
3884 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3885 		/* The wait after the last probe can be shorter */
3886 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3887 					     idev->cnf.rtr_solicits) ?
3888 				      idev->cnf.rtr_solicit_delay :
3889 				      idev->rs_interval);
3890 	} else {
3891 		/*
3892 		 * Note: we do not support deprecated "all on-link"
3893 		 * assumption any longer.
3894 		 */
3895 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3896 	}
3897 
3898 out:
3899 	write_unlock(&idev->lock);
3900 put:
3901 	in6_dev_put(idev);
3902 }
3903 
3904 /*
3905  *	Duplicate Address Detection
3906  */
3907 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3908 {
3909 	unsigned long rand_num;
3910 	struct inet6_dev *idev = ifp->idev;
3911 	u64 nonce;
3912 
3913 	if (ifp->flags & IFA_F_OPTIMISTIC)
3914 		rand_num = 0;
3915 	else
3916 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3917 
3918 	nonce = 0;
3919 	if (idev->cnf.enhanced_dad ||
3920 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3921 		do
3922 			get_random_bytes(&nonce, 6);
3923 		while (nonce == 0);
3924 	}
3925 	ifp->dad_nonce = nonce;
3926 	ifp->dad_probes = idev->cnf.dad_transmits;
3927 	addrconf_mod_dad_work(ifp, rand_num);
3928 }
3929 
3930 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3931 {
3932 	struct inet6_dev *idev = ifp->idev;
3933 	struct net_device *dev = idev->dev;
3934 	bool bump_id, notify = false;
3935 	struct net *net;
3936 
3937 	addrconf_join_solict(dev, &ifp->addr);
3938 
3939 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3940 
3941 	read_lock_bh(&idev->lock);
3942 	spin_lock(&ifp->lock);
3943 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3944 		goto out;
3945 
3946 	net = dev_net(dev);
3947 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3948 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3949 	     idev->cnf.accept_dad < 1) ||
3950 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3951 	    ifp->flags & IFA_F_NODAD) {
3952 		bool send_na = false;
3953 
3954 		if (ifp->flags & IFA_F_TENTATIVE &&
3955 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3956 			send_na = true;
3957 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3958 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3959 		spin_unlock(&ifp->lock);
3960 		read_unlock_bh(&idev->lock);
3961 
3962 		addrconf_dad_completed(ifp, bump_id, send_na);
3963 		return;
3964 	}
3965 
3966 	if (!(idev->if_flags & IF_READY)) {
3967 		spin_unlock(&ifp->lock);
3968 		read_unlock_bh(&idev->lock);
3969 		/*
3970 		 * If the device is not ready:
3971 		 * - keep it tentative if it is a permanent address.
3972 		 * - otherwise, kill it.
3973 		 */
3974 		in6_ifa_hold(ifp);
3975 		addrconf_dad_stop(ifp, 0);
3976 		return;
3977 	}
3978 
3979 	/*
3980 	 * Optimistic nodes can start receiving
3981 	 * Frames right away
3982 	 */
3983 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3984 		ip6_ins_rt(net, ifp->rt);
3985 		if (ipv6_use_optimistic_addr(net, idev)) {
3986 			/* Because optimistic nodes can use this address,
3987 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3988 			 */
3989 			notify = true;
3990 		}
3991 	}
3992 
3993 	addrconf_dad_kick(ifp);
3994 out:
3995 	spin_unlock(&ifp->lock);
3996 	read_unlock_bh(&idev->lock);
3997 	if (notify)
3998 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3999 }
4000 
4001 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4002 {
4003 	bool begin_dad = false;
4004 
4005 	spin_lock_bh(&ifp->lock);
4006 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4007 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4008 		begin_dad = true;
4009 	}
4010 	spin_unlock_bh(&ifp->lock);
4011 
4012 	if (begin_dad)
4013 		addrconf_mod_dad_work(ifp, 0);
4014 }
4015 
4016 static void addrconf_dad_work(struct work_struct *w)
4017 {
4018 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4019 						struct inet6_ifaddr,
4020 						dad_work);
4021 	struct inet6_dev *idev = ifp->idev;
4022 	bool bump_id, disable_ipv6 = false;
4023 	struct in6_addr mcaddr;
4024 
4025 	enum {
4026 		DAD_PROCESS,
4027 		DAD_BEGIN,
4028 		DAD_ABORT,
4029 	} action = DAD_PROCESS;
4030 
4031 	rtnl_lock();
4032 
4033 	spin_lock_bh(&ifp->lock);
4034 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4035 		action = DAD_BEGIN;
4036 		ifp->state = INET6_IFADDR_STATE_DAD;
4037 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4038 		action = DAD_ABORT;
4039 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4040 
4041 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4042 		     idev->cnf.accept_dad > 1) &&
4043 		    !idev->cnf.disable_ipv6 &&
4044 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4045 			struct in6_addr addr;
4046 
4047 			addr.s6_addr32[0] = htonl(0xfe800000);
4048 			addr.s6_addr32[1] = 0;
4049 
4050 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4051 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4052 				/* DAD failed for link-local based on MAC */
4053 				idev->cnf.disable_ipv6 = 1;
4054 
4055 				pr_info("%s: IPv6 being disabled!\n",
4056 					ifp->idev->dev->name);
4057 				disable_ipv6 = true;
4058 			}
4059 		}
4060 	}
4061 	spin_unlock_bh(&ifp->lock);
4062 
4063 	if (action == DAD_BEGIN) {
4064 		addrconf_dad_begin(ifp);
4065 		goto out;
4066 	} else if (action == DAD_ABORT) {
4067 		in6_ifa_hold(ifp);
4068 		addrconf_dad_stop(ifp, 1);
4069 		if (disable_ipv6)
4070 			addrconf_ifdown(idev->dev, false);
4071 		goto out;
4072 	}
4073 
4074 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4075 		goto out;
4076 
4077 	write_lock_bh(&idev->lock);
4078 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4079 		write_unlock_bh(&idev->lock);
4080 		goto out;
4081 	}
4082 
4083 	spin_lock(&ifp->lock);
4084 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4085 		spin_unlock(&ifp->lock);
4086 		write_unlock_bh(&idev->lock);
4087 		goto out;
4088 	}
4089 
4090 	if (ifp->dad_probes == 0) {
4091 		bool send_na = false;
4092 
4093 		/*
4094 		 * DAD was successful
4095 		 */
4096 
4097 		if (ifp->flags & IFA_F_TENTATIVE &&
4098 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4099 			send_na = true;
4100 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4101 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4102 		spin_unlock(&ifp->lock);
4103 		write_unlock_bh(&idev->lock);
4104 
4105 		addrconf_dad_completed(ifp, bump_id, send_na);
4106 
4107 		goto out;
4108 	}
4109 
4110 	ifp->dad_probes--;
4111 	addrconf_mod_dad_work(ifp,
4112 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4113 				  HZ/100));
4114 	spin_unlock(&ifp->lock);
4115 	write_unlock_bh(&idev->lock);
4116 
4117 	/* send a neighbour solicitation for our addr */
4118 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4119 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4120 		      ifp->dad_nonce);
4121 out:
4122 	in6_ifa_put(ifp);
4123 	rtnl_unlock();
4124 }
4125 
4126 /* ifp->idev must be at least read locked */
4127 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4128 {
4129 	struct inet6_ifaddr *ifpiter;
4130 	struct inet6_dev *idev = ifp->idev;
4131 
4132 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4133 		if (ifpiter->scope > IFA_LINK)
4134 			break;
4135 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4136 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4137 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4138 		    IFA_F_PERMANENT)
4139 			return false;
4140 	}
4141 	return true;
4142 }
4143 
4144 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4145 				   bool send_na)
4146 {
4147 	struct net_device *dev = ifp->idev->dev;
4148 	struct in6_addr lladdr;
4149 	bool send_rs, send_mld;
4150 
4151 	addrconf_del_dad_work(ifp);
4152 
4153 	/*
4154 	 *	Configure the address for reception. Now it is valid.
4155 	 */
4156 
4157 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4158 
4159 	/* If added prefix is link local and we are prepared to process
4160 	   router advertisements, start sending router solicitations.
4161 	 */
4162 
4163 	read_lock_bh(&ifp->idev->lock);
4164 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4165 	send_rs = send_mld &&
4166 		  ipv6_accept_ra(ifp->idev) &&
4167 		  ifp->idev->cnf.rtr_solicits != 0 &&
4168 		  (dev->flags&IFF_LOOPBACK) == 0;
4169 	read_unlock_bh(&ifp->idev->lock);
4170 
4171 	/* While dad is in progress mld report's source address is in6_addrany.
4172 	 * Resend with proper ll now.
4173 	 */
4174 	if (send_mld)
4175 		ipv6_mc_dad_complete(ifp->idev);
4176 
4177 	/* send unsolicited NA if enabled */
4178 	if (send_na &&
4179 	    (ifp->idev->cnf.ndisc_notify ||
4180 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4181 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4182 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4183 			      /*solicited=*/ false, /*override=*/ true,
4184 			      /*inc_opt=*/ true);
4185 	}
4186 
4187 	if (send_rs) {
4188 		/*
4189 		 *	If a host as already performed a random delay
4190 		 *	[...] as part of DAD [...] there is no need
4191 		 *	to delay again before sending the first RS
4192 		 */
4193 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4194 			return;
4195 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4196 
4197 		write_lock_bh(&ifp->idev->lock);
4198 		spin_lock(&ifp->lock);
4199 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4200 			ifp->idev->cnf.rtr_solicit_interval);
4201 		ifp->idev->rs_probes = 1;
4202 		ifp->idev->if_flags |= IF_RS_SENT;
4203 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4204 		spin_unlock(&ifp->lock);
4205 		write_unlock_bh(&ifp->idev->lock);
4206 	}
4207 
4208 	if (bump_id)
4209 		rt_genid_bump_ipv6(dev_net(dev));
4210 
4211 	/* Make sure that a new temporary address will be created
4212 	 * before this temporary address becomes deprecated.
4213 	 */
4214 	if (ifp->flags & IFA_F_TEMPORARY)
4215 		addrconf_verify_rtnl();
4216 }
4217 
4218 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4219 {
4220 	struct inet6_ifaddr *ifp;
4221 
4222 	read_lock_bh(&idev->lock);
4223 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4224 		spin_lock(&ifp->lock);
4225 		if ((ifp->flags & IFA_F_TENTATIVE &&
4226 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4227 			if (restart)
4228 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4229 			addrconf_dad_kick(ifp);
4230 		}
4231 		spin_unlock(&ifp->lock);
4232 	}
4233 	read_unlock_bh(&idev->lock);
4234 }
4235 
4236 #ifdef CONFIG_PROC_FS
4237 struct if6_iter_state {
4238 	struct seq_net_private p;
4239 	int bucket;
4240 	int offset;
4241 };
4242 
4243 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4244 {
4245 	struct if6_iter_state *state = seq->private;
4246 	struct net *net = seq_file_net(seq);
4247 	struct inet6_ifaddr *ifa = NULL;
4248 	int p = 0;
4249 
4250 	/* initial bucket if pos is 0 */
4251 	if (pos == 0) {
4252 		state->bucket = 0;
4253 		state->offset = 0;
4254 	}
4255 
4256 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4257 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4258 					 addr_lst) {
4259 			if (!net_eq(dev_net(ifa->idev->dev), net))
4260 				continue;
4261 			/* sync with offset */
4262 			if (p < state->offset) {
4263 				p++;
4264 				continue;
4265 			}
4266 			return ifa;
4267 		}
4268 
4269 		/* prepare for next bucket */
4270 		state->offset = 0;
4271 		p = 0;
4272 	}
4273 	return NULL;
4274 }
4275 
4276 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4277 					 struct inet6_ifaddr *ifa)
4278 {
4279 	struct if6_iter_state *state = seq->private;
4280 	struct net *net = seq_file_net(seq);
4281 
4282 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4283 		if (!net_eq(dev_net(ifa->idev->dev), net))
4284 			continue;
4285 		state->offset++;
4286 		return ifa;
4287 	}
4288 
4289 	state->offset = 0;
4290 	while (++state->bucket < IN6_ADDR_HSIZE) {
4291 		hlist_for_each_entry_rcu(ifa,
4292 				     &inet6_addr_lst[state->bucket], addr_lst) {
4293 			if (!net_eq(dev_net(ifa->idev->dev), net))
4294 				continue;
4295 			return ifa;
4296 		}
4297 	}
4298 
4299 	return NULL;
4300 }
4301 
4302 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4303 	__acquires(rcu)
4304 {
4305 	rcu_read_lock();
4306 	return if6_get_first(seq, *pos);
4307 }
4308 
4309 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4310 {
4311 	struct inet6_ifaddr *ifa;
4312 
4313 	ifa = if6_get_next(seq, v);
4314 	++*pos;
4315 	return ifa;
4316 }
4317 
4318 static void if6_seq_stop(struct seq_file *seq, void *v)
4319 	__releases(rcu)
4320 {
4321 	rcu_read_unlock();
4322 }
4323 
4324 static int if6_seq_show(struct seq_file *seq, void *v)
4325 {
4326 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4327 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4328 		   &ifp->addr,
4329 		   ifp->idev->dev->ifindex,
4330 		   ifp->prefix_len,
4331 		   ifp->scope,
4332 		   (u8) ifp->flags,
4333 		   ifp->idev->dev->name);
4334 	return 0;
4335 }
4336 
4337 static const struct seq_operations if6_seq_ops = {
4338 	.start	= if6_seq_start,
4339 	.next	= if6_seq_next,
4340 	.show	= if6_seq_show,
4341 	.stop	= if6_seq_stop,
4342 };
4343 
4344 static int __net_init if6_proc_net_init(struct net *net)
4345 {
4346 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4347 			sizeof(struct if6_iter_state)))
4348 		return -ENOMEM;
4349 	return 0;
4350 }
4351 
4352 static void __net_exit if6_proc_net_exit(struct net *net)
4353 {
4354 	remove_proc_entry("if_inet6", net->proc_net);
4355 }
4356 
4357 static struct pernet_operations if6_proc_net_ops = {
4358 	.init = if6_proc_net_init,
4359 	.exit = if6_proc_net_exit,
4360 };
4361 
4362 int __init if6_proc_init(void)
4363 {
4364 	return register_pernet_subsys(&if6_proc_net_ops);
4365 }
4366 
4367 void if6_proc_exit(void)
4368 {
4369 	unregister_pernet_subsys(&if6_proc_net_ops);
4370 }
4371 #endif	/* CONFIG_PROC_FS */
4372 
4373 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4374 /* Check if address is a home address configured on any interface. */
4375 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4376 {
4377 	unsigned int hash = inet6_addr_hash(net, addr);
4378 	struct inet6_ifaddr *ifp = NULL;
4379 	int ret = 0;
4380 
4381 	rcu_read_lock();
4382 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4383 		if (!net_eq(dev_net(ifp->idev->dev), net))
4384 			continue;
4385 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4386 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4387 			ret = 1;
4388 			break;
4389 		}
4390 	}
4391 	rcu_read_unlock();
4392 	return ret;
4393 }
4394 #endif
4395 
4396 /* RFC6554 has some algorithm to avoid loops in segment routing by
4397  * checking if the segments contains any of a local interface address.
4398  *
4399  * Quote:
4400  *
4401  * To detect loops in the SRH, a router MUST determine if the SRH
4402  * includes multiple addresses assigned to any interface on that router.
4403  * If such addresses appear more than once and are separated by at least
4404  * one address not assigned to that router.
4405  */
4406 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4407 			  unsigned char nsegs)
4408 {
4409 	const struct in6_addr *addr;
4410 	int i, ret = 0, found = 0;
4411 	struct inet6_ifaddr *ifp;
4412 	bool separated = false;
4413 	unsigned int hash;
4414 	bool hash_found;
4415 
4416 	rcu_read_lock();
4417 	for (i = 0; i < nsegs; i++) {
4418 		addr = &segs[i];
4419 		hash = inet6_addr_hash(net, addr);
4420 
4421 		hash_found = false;
4422 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4423 			if (!net_eq(dev_net(ifp->idev->dev), net))
4424 				continue;
4425 
4426 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4427 				hash_found = true;
4428 				break;
4429 			}
4430 		}
4431 
4432 		if (hash_found) {
4433 			if (found > 1 && separated) {
4434 				ret = 1;
4435 				break;
4436 			}
4437 
4438 			separated = false;
4439 			found++;
4440 		} else {
4441 			separated = true;
4442 		}
4443 	}
4444 	rcu_read_unlock();
4445 
4446 	return ret;
4447 }
4448 
4449 /*
4450  *	Periodic address status verification
4451  */
4452 
4453 static void addrconf_verify_rtnl(void)
4454 {
4455 	unsigned long now, next, next_sec, next_sched;
4456 	struct inet6_ifaddr *ifp;
4457 	int i;
4458 
4459 	ASSERT_RTNL();
4460 
4461 	rcu_read_lock_bh();
4462 	now = jiffies;
4463 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4464 
4465 	cancel_delayed_work(&addr_chk_work);
4466 
4467 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4468 restart:
4469 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4470 			unsigned long age;
4471 
4472 			/* When setting preferred_lft to a value not zero or
4473 			 * infinity, while valid_lft is infinity
4474 			 * IFA_F_PERMANENT has a non-infinity life time.
4475 			 */
4476 			if ((ifp->flags & IFA_F_PERMANENT) &&
4477 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4478 				continue;
4479 
4480 			spin_lock(&ifp->lock);
4481 			/* We try to batch several events at once. */
4482 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4483 
4484 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4485 			    age >= ifp->valid_lft) {
4486 				spin_unlock(&ifp->lock);
4487 				in6_ifa_hold(ifp);
4488 				ipv6_del_addr(ifp);
4489 				goto restart;
4490 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4491 				spin_unlock(&ifp->lock);
4492 				continue;
4493 			} else if (age >= ifp->prefered_lft) {
4494 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4495 				int deprecate = 0;
4496 
4497 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4498 					deprecate = 1;
4499 					ifp->flags |= IFA_F_DEPRECATED;
4500 				}
4501 
4502 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4503 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4504 					next = ifp->tstamp + ifp->valid_lft * HZ;
4505 
4506 				spin_unlock(&ifp->lock);
4507 
4508 				if (deprecate) {
4509 					in6_ifa_hold(ifp);
4510 
4511 					ipv6_ifa_notify(0, ifp);
4512 					in6_ifa_put(ifp);
4513 					goto restart;
4514 				}
4515 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4516 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4517 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4518 					ifp->idev->cnf.dad_transmits *
4519 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4520 
4521 				if (age >= ifp->prefered_lft - regen_advance) {
4522 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4523 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4524 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4525 					if (!ifp->regen_count && ifpub) {
4526 						ifp->regen_count++;
4527 						in6_ifa_hold(ifp);
4528 						in6_ifa_hold(ifpub);
4529 						spin_unlock(&ifp->lock);
4530 
4531 						spin_lock(&ifpub->lock);
4532 						ifpub->regen_count = 0;
4533 						spin_unlock(&ifpub->lock);
4534 						rcu_read_unlock_bh();
4535 						ipv6_create_tempaddr(ifpub, true);
4536 						in6_ifa_put(ifpub);
4537 						in6_ifa_put(ifp);
4538 						rcu_read_lock_bh();
4539 						goto restart;
4540 					}
4541 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4542 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4543 				spin_unlock(&ifp->lock);
4544 			} else {
4545 				/* ifp->prefered_lft <= ifp->valid_lft */
4546 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4547 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4548 				spin_unlock(&ifp->lock);
4549 			}
4550 		}
4551 	}
4552 
4553 	next_sec = round_jiffies_up(next);
4554 	next_sched = next;
4555 
4556 	/* If rounded timeout is accurate enough, accept it. */
4557 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4558 		next_sched = next_sec;
4559 
4560 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4561 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4562 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4563 
4564 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4565 		 now, next, next_sec, next_sched);
4566 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4567 	rcu_read_unlock_bh();
4568 }
4569 
4570 static void addrconf_verify_work(struct work_struct *w)
4571 {
4572 	rtnl_lock();
4573 	addrconf_verify_rtnl();
4574 	rtnl_unlock();
4575 }
4576 
4577 static void addrconf_verify(void)
4578 {
4579 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4580 }
4581 
4582 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4583 				     struct in6_addr **peer_pfx)
4584 {
4585 	struct in6_addr *pfx = NULL;
4586 
4587 	*peer_pfx = NULL;
4588 
4589 	if (addr)
4590 		pfx = nla_data(addr);
4591 
4592 	if (local) {
4593 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4594 			*peer_pfx = pfx;
4595 		pfx = nla_data(local);
4596 	}
4597 
4598 	return pfx;
4599 }
4600 
4601 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4602 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4603 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4604 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4605 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4606 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4607 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4608 };
4609 
4610 static int
4611 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4612 		  struct netlink_ext_ack *extack)
4613 {
4614 	struct net *net = sock_net(skb->sk);
4615 	struct ifaddrmsg *ifm;
4616 	struct nlattr *tb[IFA_MAX+1];
4617 	struct in6_addr *pfx, *peer_pfx;
4618 	u32 ifa_flags;
4619 	int err;
4620 
4621 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4622 				     ifa_ipv6_policy, extack);
4623 	if (err < 0)
4624 		return err;
4625 
4626 	ifm = nlmsg_data(nlh);
4627 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4628 	if (!pfx)
4629 		return -EINVAL;
4630 
4631 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4632 
4633 	/* We ignore other flags so far. */
4634 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4635 
4636 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4637 			      ifm->ifa_prefixlen);
4638 }
4639 
4640 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4641 			       unsigned long expires, u32 flags,
4642 			       bool modify_peer)
4643 {
4644 	struct fib6_info *f6i;
4645 	u32 prio;
4646 
4647 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4648 					ifp->prefix_len,
4649 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4650 	if (!f6i)
4651 		return -ENOENT;
4652 
4653 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4654 	if (f6i->fib6_metric != prio) {
4655 		/* delete old one */
4656 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4657 
4658 		/* add new one */
4659 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4660 				      ifp->prefix_len,
4661 				      ifp->rt_priority, ifp->idev->dev,
4662 				      expires, flags, GFP_KERNEL);
4663 	} else {
4664 		if (!expires)
4665 			fib6_clean_expires(f6i);
4666 		else
4667 			fib6_set_expires(f6i, expires);
4668 
4669 		fib6_info_release(f6i);
4670 	}
4671 
4672 	return 0;
4673 }
4674 
4675 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4676 {
4677 	u32 flags;
4678 	clock_t expires;
4679 	unsigned long timeout;
4680 	bool was_managetempaddr;
4681 	bool had_prefixroute;
4682 	bool new_peer = false;
4683 
4684 	ASSERT_RTNL();
4685 
4686 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4687 		return -EINVAL;
4688 
4689 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4690 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4691 		return -EINVAL;
4692 
4693 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4694 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4695 
4696 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4697 	if (addrconf_finite_timeout(timeout)) {
4698 		expires = jiffies_to_clock_t(timeout * HZ);
4699 		cfg->valid_lft = timeout;
4700 		flags = RTF_EXPIRES;
4701 	} else {
4702 		expires = 0;
4703 		flags = 0;
4704 		cfg->ifa_flags |= IFA_F_PERMANENT;
4705 	}
4706 
4707 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4708 	if (addrconf_finite_timeout(timeout)) {
4709 		if (timeout == 0)
4710 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4711 		cfg->preferred_lft = timeout;
4712 	}
4713 
4714 	if (cfg->peer_pfx &&
4715 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4716 		if (!ipv6_addr_any(&ifp->peer_addr))
4717 			cleanup_prefix_route(ifp, expires, true, true);
4718 		new_peer = true;
4719 	}
4720 
4721 	spin_lock_bh(&ifp->lock);
4722 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4723 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4724 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4725 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4726 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4727 			IFA_F_NOPREFIXROUTE);
4728 	ifp->flags |= cfg->ifa_flags;
4729 	ifp->tstamp = jiffies;
4730 	ifp->valid_lft = cfg->valid_lft;
4731 	ifp->prefered_lft = cfg->preferred_lft;
4732 
4733 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4734 		ifp->rt_priority = cfg->rt_priority;
4735 
4736 	if (new_peer)
4737 		ifp->peer_addr = *cfg->peer_pfx;
4738 
4739 	spin_unlock_bh(&ifp->lock);
4740 	if (!(ifp->flags&IFA_F_TENTATIVE))
4741 		ipv6_ifa_notify(0, ifp);
4742 
4743 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4744 		int rc = -ENOENT;
4745 
4746 		if (had_prefixroute)
4747 			rc = modify_prefix_route(ifp, expires, flags, false);
4748 
4749 		/* prefix route could have been deleted; if so restore it */
4750 		if (rc == -ENOENT) {
4751 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4752 					      ifp->rt_priority, ifp->idev->dev,
4753 					      expires, flags, GFP_KERNEL);
4754 		}
4755 
4756 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4757 			rc = modify_prefix_route(ifp, expires, flags, true);
4758 
4759 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4760 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4761 					      ifp->rt_priority, ifp->idev->dev,
4762 					      expires, flags, GFP_KERNEL);
4763 		}
4764 	} else if (had_prefixroute) {
4765 		enum cleanup_prefix_rt_t action;
4766 		unsigned long rt_expires;
4767 
4768 		write_lock_bh(&ifp->idev->lock);
4769 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4770 		write_unlock_bh(&ifp->idev->lock);
4771 
4772 		if (action != CLEANUP_PREFIX_RT_NOP) {
4773 			cleanup_prefix_route(ifp, rt_expires,
4774 				action == CLEANUP_PREFIX_RT_DEL, false);
4775 		}
4776 	}
4777 
4778 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4779 		if (was_managetempaddr &&
4780 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4781 			cfg->valid_lft = 0;
4782 			cfg->preferred_lft = 0;
4783 		}
4784 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4785 				 cfg->preferred_lft, !was_managetempaddr,
4786 				 jiffies);
4787 	}
4788 
4789 	addrconf_verify_rtnl();
4790 
4791 	return 0;
4792 }
4793 
4794 static int
4795 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4796 		  struct netlink_ext_ack *extack)
4797 {
4798 	struct net *net = sock_net(skb->sk);
4799 	struct ifaddrmsg *ifm;
4800 	struct nlattr *tb[IFA_MAX+1];
4801 	struct in6_addr *peer_pfx;
4802 	struct inet6_ifaddr *ifa;
4803 	struct net_device *dev;
4804 	struct inet6_dev *idev;
4805 	struct ifa6_config cfg;
4806 	int err;
4807 
4808 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4809 				     ifa_ipv6_policy, extack);
4810 	if (err < 0)
4811 		return err;
4812 
4813 	memset(&cfg, 0, sizeof(cfg));
4814 
4815 	ifm = nlmsg_data(nlh);
4816 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4817 	if (!cfg.pfx)
4818 		return -EINVAL;
4819 
4820 	cfg.peer_pfx = peer_pfx;
4821 	cfg.plen = ifm->ifa_prefixlen;
4822 	if (tb[IFA_RT_PRIORITY])
4823 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4824 
4825 	cfg.valid_lft = INFINITY_LIFE_TIME;
4826 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4827 
4828 	if (tb[IFA_CACHEINFO]) {
4829 		struct ifa_cacheinfo *ci;
4830 
4831 		ci = nla_data(tb[IFA_CACHEINFO]);
4832 		cfg.valid_lft = ci->ifa_valid;
4833 		cfg.preferred_lft = ci->ifa_prefered;
4834 	}
4835 
4836 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4837 	if (!dev)
4838 		return -ENODEV;
4839 
4840 	if (tb[IFA_FLAGS])
4841 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4842 	else
4843 		cfg.ifa_flags = ifm->ifa_flags;
4844 
4845 	/* We ignore other flags so far. */
4846 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4847 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4848 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4849 
4850 	idev = ipv6_find_idev(dev);
4851 	if (IS_ERR(idev))
4852 		return PTR_ERR(idev);
4853 
4854 	if (!ipv6_allow_optimistic_dad(net, idev))
4855 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4856 
4857 	if (cfg.ifa_flags & IFA_F_NODAD &&
4858 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4859 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4860 		return -EINVAL;
4861 	}
4862 
4863 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4864 	if (!ifa) {
4865 		/*
4866 		 * It would be best to check for !NLM_F_CREATE here but
4867 		 * userspace already relies on not having to provide this.
4868 		 */
4869 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4870 	}
4871 
4872 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4873 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4874 		err = -EEXIST;
4875 	else
4876 		err = inet6_addr_modify(ifa, &cfg);
4877 
4878 	in6_ifa_put(ifa);
4879 
4880 	return err;
4881 }
4882 
4883 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4884 			  u8 scope, int ifindex)
4885 {
4886 	struct ifaddrmsg *ifm;
4887 
4888 	ifm = nlmsg_data(nlh);
4889 	ifm->ifa_family = AF_INET6;
4890 	ifm->ifa_prefixlen = prefixlen;
4891 	ifm->ifa_flags = flags;
4892 	ifm->ifa_scope = scope;
4893 	ifm->ifa_index = ifindex;
4894 }
4895 
4896 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4897 			 unsigned long tstamp, u32 preferred, u32 valid)
4898 {
4899 	struct ifa_cacheinfo ci;
4900 
4901 	ci.cstamp = cstamp_delta(cstamp);
4902 	ci.tstamp = cstamp_delta(tstamp);
4903 	ci.ifa_prefered = preferred;
4904 	ci.ifa_valid = valid;
4905 
4906 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4907 }
4908 
4909 static inline int rt_scope(int ifa_scope)
4910 {
4911 	if (ifa_scope & IFA_HOST)
4912 		return RT_SCOPE_HOST;
4913 	else if (ifa_scope & IFA_LINK)
4914 		return RT_SCOPE_LINK;
4915 	else if (ifa_scope & IFA_SITE)
4916 		return RT_SCOPE_SITE;
4917 	else
4918 		return RT_SCOPE_UNIVERSE;
4919 }
4920 
4921 static inline int inet6_ifaddr_msgsize(void)
4922 {
4923 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4924 	       + nla_total_size(16) /* IFA_LOCAL */
4925 	       + nla_total_size(16) /* IFA_ADDRESS */
4926 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4927 	       + nla_total_size(4)  /* IFA_FLAGS */
4928 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4929 }
4930 
4931 enum addr_type_t {
4932 	UNICAST_ADDR,
4933 	MULTICAST_ADDR,
4934 	ANYCAST_ADDR,
4935 };
4936 
4937 struct inet6_fill_args {
4938 	u32 portid;
4939 	u32 seq;
4940 	int event;
4941 	unsigned int flags;
4942 	int netnsid;
4943 	int ifindex;
4944 	enum addr_type_t type;
4945 };
4946 
4947 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4948 			     struct inet6_fill_args *args)
4949 {
4950 	struct nlmsghdr  *nlh;
4951 	u32 preferred, valid;
4952 
4953 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4954 			sizeof(struct ifaddrmsg), args->flags);
4955 	if (!nlh)
4956 		return -EMSGSIZE;
4957 
4958 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4959 		      ifa->idev->dev->ifindex);
4960 
4961 	if (args->netnsid >= 0 &&
4962 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4963 		goto error;
4964 
4965 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4966 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4967 		preferred = ifa->prefered_lft;
4968 		valid = ifa->valid_lft;
4969 		if (preferred != INFINITY_LIFE_TIME) {
4970 			long tval = (jiffies - ifa->tstamp)/HZ;
4971 			if (preferred > tval)
4972 				preferred -= tval;
4973 			else
4974 				preferred = 0;
4975 			if (valid != INFINITY_LIFE_TIME) {
4976 				if (valid > tval)
4977 					valid -= tval;
4978 				else
4979 					valid = 0;
4980 			}
4981 		}
4982 	} else {
4983 		preferred = INFINITY_LIFE_TIME;
4984 		valid = INFINITY_LIFE_TIME;
4985 	}
4986 
4987 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4988 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4989 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4990 			goto error;
4991 	} else
4992 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4993 			goto error;
4994 
4995 	if (ifa->rt_priority &&
4996 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4997 		goto error;
4998 
4999 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5000 		goto error;
5001 
5002 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5003 		goto error;
5004 
5005 	nlmsg_end(skb, nlh);
5006 	return 0;
5007 
5008 error:
5009 	nlmsg_cancel(skb, nlh);
5010 	return -EMSGSIZE;
5011 }
5012 
5013 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5014 			       struct inet6_fill_args *args)
5015 {
5016 	struct nlmsghdr  *nlh;
5017 	u8 scope = RT_SCOPE_UNIVERSE;
5018 	int ifindex = ifmca->idev->dev->ifindex;
5019 
5020 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5021 		scope = RT_SCOPE_SITE;
5022 
5023 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5024 			sizeof(struct ifaddrmsg), args->flags);
5025 	if (!nlh)
5026 		return -EMSGSIZE;
5027 
5028 	if (args->netnsid >= 0 &&
5029 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5030 		nlmsg_cancel(skb, nlh);
5031 		return -EMSGSIZE;
5032 	}
5033 
5034 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5035 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5036 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5037 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5038 		nlmsg_cancel(skb, nlh);
5039 		return -EMSGSIZE;
5040 	}
5041 
5042 	nlmsg_end(skb, nlh);
5043 	return 0;
5044 }
5045 
5046 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5047 			       struct inet6_fill_args *args)
5048 {
5049 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5050 	int ifindex = dev ? dev->ifindex : 1;
5051 	struct nlmsghdr  *nlh;
5052 	u8 scope = RT_SCOPE_UNIVERSE;
5053 
5054 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5055 		scope = RT_SCOPE_SITE;
5056 
5057 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5058 			sizeof(struct ifaddrmsg), args->flags);
5059 	if (!nlh)
5060 		return -EMSGSIZE;
5061 
5062 	if (args->netnsid >= 0 &&
5063 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5064 		nlmsg_cancel(skb, nlh);
5065 		return -EMSGSIZE;
5066 	}
5067 
5068 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5069 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5070 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5071 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5072 		nlmsg_cancel(skb, nlh);
5073 		return -EMSGSIZE;
5074 	}
5075 
5076 	nlmsg_end(skb, nlh);
5077 	return 0;
5078 }
5079 
5080 /* called with rcu_read_lock() */
5081 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5082 			  struct netlink_callback *cb, int s_ip_idx,
5083 			  struct inet6_fill_args *fillargs)
5084 {
5085 	struct ifmcaddr6 *ifmca;
5086 	struct ifacaddr6 *ifaca;
5087 	int ip_idx = 0;
5088 	int err = 1;
5089 
5090 	read_lock_bh(&idev->lock);
5091 	switch (fillargs->type) {
5092 	case UNICAST_ADDR: {
5093 		struct inet6_ifaddr *ifa;
5094 		fillargs->event = RTM_NEWADDR;
5095 
5096 		/* unicast address incl. temp addr */
5097 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5098 			if (ip_idx < s_ip_idx)
5099 				goto next;
5100 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5101 			if (err < 0)
5102 				break;
5103 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5104 next:
5105 			ip_idx++;
5106 		}
5107 		break;
5108 	}
5109 	case MULTICAST_ADDR:
5110 		fillargs->event = RTM_GETMULTICAST;
5111 
5112 		/* multicast address */
5113 		for (ifmca = idev->mc_list; ifmca;
5114 		     ifmca = ifmca->next, ip_idx++) {
5115 			if (ip_idx < s_ip_idx)
5116 				continue;
5117 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5118 			if (err < 0)
5119 				break;
5120 		}
5121 		break;
5122 	case ANYCAST_ADDR:
5123 		fillargs->event = RTM_GETANYCAST;
5124 		/* anycast address */
5125 		for (ifaca = idev->ac_list; ifaca;
5126 		     ifaca = ifaca->aca_next, ip_idx++) {
5127 			if (ip_idx < s_ip_idx)
5128 				continue;
5129 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5130 			if (err < 0)
5131 				break;
5132 		}
5133 		break;
5134 	default:
5135 		break;
5136 	}
5137 	read_unlock_bh(&idev->lock);
5138 	cb->args[2] = ip_idx;
5139 	return err;
5140 }
5141 
5142 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5143 				       struct inet6_fill_args *fillargs,
5144 				       struct net **tgt_net, struct sock *sk,
5145 				       struct netlink_callback *cb)
5146 {
5147 	struct netlink_ext_ack *extack = cb->extack;
5148 	struct nlattr *tb[IFA_MAX+1];
5149 	struct ifaddrmsg *ifm;
5150 	int err, i;
5151 
5152 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5153 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5154 		return -EINVAL;
5155 	}
5156 
5157 	ifm = nlmsg_data(nlh);
5158 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5159 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5160 		return -EINVAL;
5161 	}
5162 
5163 	fillargs->ifindex = ifm->ifa_index;
5164 	if (fillargs->ifindex) {
5165 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5166 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5167 	}
5168 
5169 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5170 					    ifa_ipv6_policy, extack);
5171 	if (err < 0)
5172 		return err;
5173 
5174 	for (i = 0; i <= IFA_MAX; ++i) {
5175 		if (!tb[i])
5176 			continue;
5177 
5178 		if (i == IFA_TARGET_NETNSID) {
5179 			struct net *net;
5180 
5181 			fillargs->netnsid = nla_get_s32(tb[i]);
5182 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5183 			if (IS_ERR(net)) {
5184 				fillargs->netnsid = -1;
5185 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5186 				return PTR_ERR(net);
5187 			}
5188 			*tgt_net = net;
5189 		} else {
5190 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5191 			return -EINVAL;
5192 		}
5193 	}
5194 
5195 	return 0;
5196 }
5197 
5198 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5199 			   enum addr_type_t type)
5200 {
5201 	const struct nlmsghdr *nlh = cb->nlh;
5202 	struct inet6_fill_args fillargs = {
5203 		.portid = NETLINK_CB(cb->skb).portid,
5204 		.seq = cb->nlh->nlmsg_seq,
5205 		.flags = NLM_F_MULTI,
5206 		.netnsid = -1,
5207 		.type = type,
5208 	};
5209 	struct net *net = sock_net(skb->sk);
5210 	struct net *tgt_net = net;
5211 	int idx, s_idx, s_ip_idx;
5212 	int h, s_h;
5213 	struct net_device *dev;
5214 	struct inet6_dev *idev;
5215 	struct hlist_head *head;
5216 	int err = 0;
5217 
5218 	s_h = cb->args[0];
5219 	s_idx = idx = cb->args[1];
5220 	s_ip_idx = cb->args[2];
5221 
5222 	if (cb->strict_check) {
5223 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5224 						  skb->sk, cb);
5225 		if (err < 0)
5226 			goto put_tgt_net;
5227 
5228 		err = 0;
5229 		if (fillargs.ifindex) {
5230 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5231 			if (!dev) {
5232 				err = -ENODEV;
5233 				goto put_tgt_net;
5234 			}
5235 			idev = __in6_dev_get(dev);
5236 			if (idev) {
5237 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5238 						     &fillargs);
5239 				if (err > 0)
5240 					err = 0;
5241 			}
5242 			goto put_tgt_net;
5243 		}
5244 	}
5245 
5246 	rcu_read_lock();
5247 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5248 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5249 		idx = 0;
5250 		head = &tgt_net->dev_index_head[h];
5251 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5252 			if (idx < s_idx)
5253 				goto cont;
5254 			if (h > s_h || idx > s_idx)
5255 				s_ip_idx = 0;
5256 			idev = __in6_dev_get(dev);
5257 			if (!idev)
5258 				goto cont;
5259 
5260 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5261 					   &fillargs) < 0)
5262 				goto done;
5263 cont:
5264 			idx++;
5265 		}
5266 	}
5267 done:
5268 	rcu_read_unlock();
5269 	cb->args[0] = h;
5270 	cb->args[1] = idx;
5271 put_tgt_net:
5272 	if (fillargs.netnsid >= 0)
5273 		put_net(tgt_net);
5274 
5275 	return skb->len ? : err;
5276 }
5277 
5278 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5279 {
5280 	enum addr_type_t type = UNICAST_ADDR;
5281 
5282 	return inet6_dump_addr(skb, cb, type);
5283 }
5284 
5285 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5286 {
5287 	enum addr_type_t type = MULTICAST_ADDR;
5288 
5289 	return inet6_dump_addr(skb, cb, type);
5290 }
5291 
5292 
5293 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5294 {
5295 	enum addr_type_t type = ANYCAST_ADDR;
5296 
5297 	return inet6_dump_addr(skb, cb, type);
5298 }
5299 
5300 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5301 				       const struct nlmsghdr *nlh,
5302 				       struct nlattr **tb,
5303 				       struct netlink_ext_ack *extack)
5304 {
5305 	struct ifaddrmsg *ifm;
5306 	int i, err;
5307 
5308 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5309 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5310 		return -EINVAL;
5311 	}
5312 
5313 	if (!netlink_strict_get_check(skb))
5314 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5315 					      ifa_ipv6_policy, extack);
5316 
5317 	ifm = nlmsg_data(nlh);
5318 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5319 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5320 		return -EINVAL;
5321 	}
5322 
5323 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5324 					    ifa_ipv6_policy, extack);
5325 	if (err)
5326 		return err;
5327 
5328 	for (i = 0; i <= IFA_MAX; i++) {
5329 		if (!tb[i])
5330 			continue;
5331 
5332 		switch (i) {
5333 		case IFA_TARGET_NETNSID:
5334 		case IFA_ADDRESS:
5335 		case IFA_LOCAL:
5336 			break;
5337 		default:
5338 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5339 			return -EINVAL;
5340 		}
5341 	}
5342 
5343 	return 0;
5344 }
5345 
5346 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5347 			     struct netlink_ext_ack *extack)
5348 {
5349 	struct net *net = sock_net(in_skb->sk);
5350 	struct inet6_fill_args fillargs = {
5351 		.portid = NETLINK_CB(in_skb).portid,
5352 		.seq = nlh->nlmsg_seq,
5353 		.event = RTM_NEWADDR,
5354 		.flags = 0,
5355 		.netnsid = -1,
5356 	};
5357 	struct net *tgt_net = net;
5358 	struct ifaddrmsg *ifm;
5359 	struct nlattr *tb[IFA_MAX+1];
5360 	struct in6_addr *addr = NULL, *peer;
5361 	struct net_device *dev = NULL;
5362 	struct inet6_ifaddr *ifa;
5363 	struct sk_buff *skb;
5364 	int err;
5365 
5366 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5367 	if (err < 0)
5368 		return err;
5369 
5370 	if (tb[IFA_TARGET_NETNSID]) {
5371 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5372 
5373 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5374 						  fillargs.netnsid);
5375 		if (IS_ERR(tgt_net))
5376 			return PTR_ERR(tgt_net);
5377 	}
5378 
5379 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5380 	if (!addr)
5381 		return -EINVAL;
5382 
5383 	ifm = nlmsg_data(nlh);
5384 	if (ifm->ifa_index)
5385 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5386 
5387 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5388 	if (!ifa) {
5389 		err = -EADDRNOTAVAIL;
5390 		goto errout;
5391 	}
5392 
5393 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5394 	if (!skb) {
5395 		err = -ENOBUFS;
5396 		goto errout_ifa;
5397 	}
5398 
5399 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5400 	if (err < 0) {
5401 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5402 		WARN_ON(err == -EMSGSIZE);
5403 		kfree_skb(skb);
5404 		goto errout_ifa;
5405 	}
5406 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5407 errout_ifa:
5408 	in6_ifa_put(ifa);
5409 errout:
5410 	if (dev)
5411 		dev_put(dev);
5412 	if (fillargs.netnsid >= 0)
5413 		put_net(tgt_net);
5414 
5415 	return err;
5416 }
5417 
5418 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5419 {
5420 	struct sk_buff *skb;
5421 	struct net *net = dev_net(ifa->idev->dev);
5422 	struct inet6_fill_args fillargs = {
5423 		.portid = 0,
5424 		.seq = 0,
5425 		.event = event,
5426 		.flags = 0,
5427 		.netnsid = -1,
5428 	};
5429 	int err = -ENOBUFS;
5430 
5431 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5432 	if (!skb)
5433 		goto errout;
5434 
5435 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5436 	if (err < 0) {
5437 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5438 		WARN_ON(err == -EMSGSIZE);
5439 		kfree_skb(skb);
5440 		goto errout;
5441 	}
5442 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5443 	return;
5444 errout:
5445 	if (err < 0)
5446 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5447 }
5448 
5449 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5450 				__s32 *array, int bytes)
5451 {
5452 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5453 
5454 	memset(array, 0, bytes);
5455 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5456 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5457 	array[DEVCONF_MTU6] = cnf->mtu6;
5458 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5459 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5460 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5461 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5462 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5463 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5464 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5465 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5466 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5467 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5468 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5469 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5470 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5471 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5472 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5473 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5474 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5475 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5476 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5477 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5478 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5479 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5480 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5481 	array[DEVCONF_RA_DEFRTR_METRIC] = cnf->ra_defrtr_metric;
5482 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5483 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5484 #ifdef CONFIG_IPV6_ROUTER_PREF
5485 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5486 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5487 		jiffies_to_msecs(cnf->rtr_probe_interval);
5488 #ifdef CONFIG_IPV6_ROUTE_INFO
5489 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5490 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5491 #endif
5492 #endif
5493 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5494 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5495 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5496 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5497 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5498 #endif
5499 #ifdef CONFIG_IPV6_MROUTE
5500 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5501 #endif
5502 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5503 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5504 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5505 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5506 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5507 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5508 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5509 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5510 	/* we omit DEVCONF_STABLE_SECRET for now */
5511 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5512 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5513 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5514 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5515 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5516 #ifdef CONFIG_IPV6_SEG6_HMAC
5517 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5518 #endif
5519 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5520 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5521 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5522 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5523 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5524 }
5525 
5526 static inline size_t inet6_ifla6_size(void)
5527 {
5528 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5529 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5530 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5531 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5532 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5533 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5534 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5535 	     + 0;
5536 }
5537 
5538 static inline size_t inet6_if_nlmsg_size(void)
5539 {
5540 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5541 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5542 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5543 	       + nla_total_size(4) /* IFLA_MTU */
5544 	       + nla_total_size(4) /* IFLA_LINK */
5545 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5546 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5547 }
5548 
5549 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5550 					int bytes)
5551 {
5552 	int i;
5553 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5554 	BUG_ON(pad < 0);
5555 
5556 	/* Use put_unaligned() because stats may not be aligned for u64. */
5557 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5558 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5559 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5560 
5561 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5562 }
5563 
5564 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5565 					int bytes, size_t syncpoff)
5566 {
5567 	int i, c;
5568 	u64 buff[IPSTATS_MIB_MAX];
5569 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5570 
5571 	BUG_ON(pad < 0);
5572 
5573 	memset(buff, 0, sizeof(buff));
5574 	buff[0] = IPSTATS_MIB_MAX;
5575 
5576 	for_each_possible_cpu(c) {
5577 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5578 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5579 	}
5580 
5581 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5582 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5583 }
5584 
5585 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5586 			     int bytes)
5587 {
5588 	switch (attrtype) {
5589 	case IFLA_INET6_STATS:
5590 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5591 				     offsetof(struct ipstats_mib, syncp));
5592 		break;
5593 	case IFLA_INET6_ICMP6STATS:
5594 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5595 		break;
5596 	}
5597 }
5598 
5599 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5600 				  u32 ext_filter_mask)
5601 {
5602 	struct nlattr *nla;
5603 	struct ifla_cacheinfo ci;
5604 
5605 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5606 		goto nla_put_failure;
5607 	ci.max_reasm_len = IPV6_MAXPLEN;
5608 	ci.tstamp = cstamp_delta(idev->tstamp);
5609 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5610 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5611 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5612 		goto nla_put_failure;
5613 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5614 	if (!nla)
5615 		goto nla_put_failure;
5616 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5617 
5618 	/* XXX - MC not implemented */
5619 
5620 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5621 		return 0;
5622 
5623 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5624 	if (!nla)
5625 		goto nla_put_failure;
5626 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5627 
5628 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5629 	if (!nla)
5630 		goto nla_put_failure;
5631 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5632 
5633 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5634 	if (!nla)
5635 		goto nla_put_failure;
5636 	read_lock_bh(&idev->lock);
5637 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5638 	read_unlock_bh(&idev->lock);
5639 
5640 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5641 		goto nla_put_failure;
5642 
5643 	return 0;
5644 
5645 nla_put_failure:
5646 	return -EMSGSIZE;
5647 }
5648 
5649 static size_t inet6_get_link_af_size(const struct net_device *dev,
5650 				     u32 ext_filter_mask)
5651 {
5652 	if (!__in6_dev_get(dev))
5653 		return 0;
5654 
5655 	return inet6_ifla6_size();
5656 }
5657 
5658 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5659 			      u32 ext_filter_mask)
5660 {
5661 	struct inet6_dev *idev = __in6_dev_get(dev);
5662 
5663 	if (!idev)
5664 		return -ENODATA;
5665 
5666 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5667 		return -EMSGSIZE;
5668 
5669 	return 0;
5670 }
5671 
5672 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5673 {
5674 	struct inet6_ifaddr *ifp;
5675 	struct net_device *dev = idev->dev;
5676 	bool clear_token, update_rs = false;
5677 	struct in6_addr ll_addr;
5678 
5679 	ASSERT_RTNL();
5680 
5681 	if (!token)
5682 		return -EINVAL;
5683 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5684 		return -EINVAL;
5685 	if (!ipv6_accept_ra(idev))
5686 		return -EINVAL;
5687 	if (idev->cnf.rtr_solicits == 0)
5688 		return -EINVAL;
5689 
5690 	write_lock_bh(&idev->lock);
5691 
5692 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5693 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5694 
5695 	write_unlock_bh(&idev->lock);
5696 
5697 	clear_token = ipv6_addr_any(token);
5698 	if (clear_token)
5699 		goto update_lft;
5700 
5701 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5702 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5703 			     IFA_F_OPTIMISTIC)) {
5704 		/* If we're not ready, then normal ifup will take care
5705 		 * of this. Otherwise, we need to request our rs here.
5706 		 */
5707 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5708 		update_rs = true;
5709 	}
5710 
5711 update_lft:
5712 	write_lock_bh(&idev->lock);
5713 
5714 	if (update_rs) {
5715 		idev->if_flags |= IF_RS_SENT;
5716 		idev->rs_interval = rfc3315_s14_backoff_init(
5717 			idev->cnf.rtr_solicit_interval);
5718 		idev->rs_probes = 1;
5719 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5720 	}
5721 
5722 	/* Well, that's kinda nasty ... */
5723 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5724 		spin_lock(&ifp->lock);
5725 		if (ifp->tokenized) {
5726 			ifp->valid_lft = 0;
5727 			ifp->prefered_lft = 0;
5728 		}
5729 		spin_unlock(&ifp->lock);
5730 	}
5731 
5732 	write_unlock_bh(&idev->lock);
5733 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5734 	addrconf_verify_rtnl();
5735 	return 0;
5736 }
5737 
5738 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5739 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5740 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5741 };
5742 
5743 static int check_addr_gen_mode(int mode)
5744 {
5745 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5746 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5747 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5748 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5749 		return -EINVAL;
5750 	return 1;
5751 }
5752 
5753 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5754 				int mode)
5755 {
5756 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5757 	    !idev->cnf.stable_secret.initialized &&
5758 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5759 		return -EINVAL;
5760 	return 1;
5761 }
5762 
5763 static int inet6_validate_link_af(const struct net_device *dev,
5764 				  const struct nlattr *nla)
5765 {
5766 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5767 	struct inet6_dev *idev = NULL;
5768 	int err;
5769 
5770 	if (dev) {
5771 		idev = __in6_dev_get(dev);
5772 		if (!idev)
5773 			return -EAFNOSUPPORT;
5774 	}
5775 
5776 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5777 					  inet6_af_policy, NULL);
5778 	if (err)
5779 		return err;
5780 
5781 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5782 		return -EINVAL;
5783 
5784 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5785 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5786 
5787 		if (check_addr_gen_mode(mode) < 0)
5788 			return -EINVAL;
5789 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5790 			return -EINVAL;
5791 	}
5792 
5793 	return 0;
5794 }
5795 
5796 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5797 {
5798 	struct inet6_dev *idev = __in6_dev_get(dev);
5799 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5800 	int err;
5801 
5802 	if (!idev)
5803 		return -EAFNOSUPPORT;
5804 
5805 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5806 		BUG();
5807 
5808 	if (tb[IFLA_INET6_TOKEN]) {
5809 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5810 		if (err)
5811 			return err;
5812 	}
5813 
5814 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5815 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5816 
5817 		idev->cnf.addr_gen_mode = mode;
5818 	}
5819 
5820 	return 0;
5821 }
5822 
5823 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5824 			     u32 portid, u32 seq, int event, unsigned int flags)
5825 {
5826 	struct net_device *dev = idev->dev;
5827 	struct ifinfomsg *hdr;
5828 	struct nlmsghdr *nlh;
5829 	void *protoinfo;
5830 
5831 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5832 	if (!nlh)
5833 		return -EMSGSIZE;
5834 
5835 	hdr = nlmsg_data(nlh);
5836 	hdr->ifi_family = AF_INET6;
5837 	hdr->__ifi_pad = 0;
5838 	hdr->ifi_type = dev->type;
5839 	hdr->ifi_index = dev->ifindex;
5840 	hdr->ifi_flags = dev_get_flags(dev);
5841 	hdr->ifi_change = 0;
5842 
5843 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5844 	    (dev->addr_len &&
5845 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5846 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5847 	    (dev->ifindex != dev_get_iflink(dev) &&
5848 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5849 	    nla_put_u8(skb, IFLA_OPERSTATE,
5850 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5851 		goto nla_put_failure;
5852 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5853 	if (!protoinfo)
5854 		goto nla_put_failure;
5855 
5856 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5857 		goto nla_put_failure;
5858 
5859 	nla_nest_end(skb, protoinfo);
5860 	nlmsg_end(skb, nlh);
5861 	return 0;
5862 
5863 nla_put_failure:
5864 	nlmsg_cancel(skb, nlh);
5865 	return -EMSGSIZE;
5866 }
5867 
5868 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5869 				   struct netlink_ext_ack *extack)
5870 {
5871 	struct ifinfomsg *ifm;
5872 
5873 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5874 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5875 		return -EINVAL;
5876 	}
5877 
5878 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5879 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5880 		return -EINVAL;
5881 	}
5882 
5883 	ifm = nlmsg_data(nlh);
5884 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5885 	    ifm->ifi_change || ifm->ifi_index) {
5886 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5887 		return -EINVAL;
5888 	}
5889 
5890 	return 0;
5891 }
5892 
5893 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5894 {
5895 	struct net *net = sock_net(skb->sk);
5896 	int h, s_h;
5897 	int idx = 0, s_idx;
5898 	struct net_device *dev;
5899 	struct inet6_dev *idev;
5900 	struct hlist_head *head;
5901 
5902 	/* only requests using strict checking can pass data to
5903 	 * influence the dump
5904 	 */
5905 	if (cb->strict_check) {
5906 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5907 
5908 		if (err < 0)
5909 			return err;
5910 	}
5911 
5912 	s_h = cb->args[0];
5913 	s_idx = cb->args[1];
5914 
5915 	rcu_read_lock();
5916 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5917 		idx = 0;
5918 		head = &net->dev_index_head[h];
5919 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5920 			if (idx < s_idx)
5921 				goto cont;
5922 			idev = __in6_dev_get(dev);
5923 			if (!idev)
5924 				goto cont;
5925 			if (inet6_fill_ifinfo(skb, idev,
5926 					      NETLINK_CB(cb->skb).portid,
5927 					      cb->nlh->nlmsg_seq,
5928 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5929 				goto out;
5930 cont:
5931 			idx++;
5932 		}
5933 	}
5934 out:
5935 	rcu_read_unlock();
5936 	cb->args[1] = idx;
5937 	cb->args[0] = h;
5938 
5939 	return skb->len;
5940 }
5941 
5942 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5943 {
5944 	struct sk_buff *skb;
5945 	struct net *net = dev_net(idev->dev);
5946 	int err = -ENOBUFS;
5947 
5948 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5949 	if (!skb)
5950 		goto errout;
5951 
5952 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5953 	if (err < 0) {
5954 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5955 		WARN_ON(err == -EMSGSIZE);
5956 		kfree_skb(skb);
5957 		goto errout;
5958 	}
5959 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5960 	return;
5961 errout:
5962 	if (err < 0)
5963 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5964 }
5965 
5966 static inline size_t inet6_prefix_nlmsg_size(void)
5967 {
5968 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5969 	       + nla_total_size(sizeof(struct in6_addr))
5970 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5971 }
5972 
5973 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5974 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5975 			     int event, unsigned int flags)
5976 {
5977 	struct prefixmsg *pmsg;
5978 	struct nlmsghdr *nlh;
5979 	struct prefix_cacheinfo	ci;
5980 
5981 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5982 	if (!nlh)
5983 		return -EMSGSIZE;
5984 
5985 	pmsg = nlmsg_data(nlh);
5986 	pmsg->prefix_family = AF_INET6;
5987 	pmsg->prefix_pad1 = 0;
5988 	pmsg->prefix_pad2 = 0;
5989 	pmsg->prefix_ifindex = idev->dev->ifindex;
5990 	pmsg->prefix_len = pinfo->prefix_len;
5991 	pmsg->prefix_type = pinfo->type;
5992 	pmsg->prefix_pad3 = 0;
5993 	pmsg->prefix_flags = 0;
5994 	if (pinfo->onlink)
5995 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5996 	if (pinfo->autoconf)
5997 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5998 
5999 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6000 		goto nla_put_failure;
6001 	ci.preferred_time = ntohl(pinfo->prefered);
6002 	ci.valid_time = ntohl(pinfo->valid);
6003 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6004 		goto nla_put_failure;
6005 	nlmsg_end(skb, nlh);
6006 	return 0;
6007 
6008 nla_put_failure:
6009 	nlmsg_cancel(skb, nlh);
6010 	return -EMSGSIZE;
6011 }
6012 
6013 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6014 			 struct prefix_info *pinfo)
6015 {
6016 	struct sk_buff *skb;
6017 	struct net *net = dev_net(idev->dev);
6018 	int err = -ENOBUFS;
6019 
6020 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6021 	if (!skb)
6022 		goto errout;
6023 
6024 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6025 	if (err < 0) {
6026 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6027 		WARN_ON(err == -EMSGSIZE);
6028 		kfree_skb(skb);
6029 		goto errout;
6030 	}
6031 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6032 	return;
6033 errout:
6034 	if (err < 0)
6035 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6036 }
6037 
6038 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6039 {
6040 	struct net *net = dev_net(ifp->idev->dev);
6041 
6042 	if (event)
6043 		ASSERT_RTNL();
6044 
6045 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6046 
6047 	switch (event) {
6048 	case RTM_NEWADDR:
6049 		/*
6050 		 * If the address was optimistic we inserted the route at the
6051 		 * start of our DAD process, so we don't need to do it again.
6052 		 * If the device was taken down in the middle of the DAD
6053 		 * cycle there is a race where we could get here without a
6054 		 * host route, so nothing to insert. That will be fixed when
6055 		 * the device is brought up.
6056 		 */
6057 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6058 			ip6_ins_rt(net, ifp->rt);
6059 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6060 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6061 				&ifp->addr, ifp->idev->dev->name);
6062 		}
6063 
6064 		if (ifp->idev->cnf.forwarding)
6065 			addrconf_join_anycast(ifp);
6066 		if (!ipv6_addr_any(&ifp->peer_addr))
6067 			addrconf_prefix_route(&ifp->peer_addr, 128,
6068 					      ifp->rt_priority, ifp->idev->dev,
6069 					      0, 0, GFP_ATOMIC);
6070 		break;
6071 	case RTM_DELADDR:
6072 		if (ifp->idev->cnf.forwarding)
6073 			addrconf_leave_anycast(ifp);
6074 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6075 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6076 			struct fib6_info *rt;
6077 
6078 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6079 						       ifp->idev->dev, 0, 0,
6080 						       false);
6081 			if (rt)
6082 				ip6_del_rt(net, rt, false);
6083 		}
6084 		if (ifp->rt) {
6085 			ip6_del_rt(net, ifp->rt, false);
6086 			ifp->rt = NULL;
6087 		}
6088 		rt_genid_bump_ipv6(net);
6089 		break;
6090 	}
6091 	atomic_inc(&net->ipv6.dev_addr_genid);
6092 }
6093 
6094 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6095 {
6096 	rcu_read_lock_bh();
6097 	if (likely(ifp->idev->dead == 0))
6098 		__ipv6_ifa_notify(event, ifp);
6099 	rcu_read_unlock_bh();
6100 }
6101 
6102 #ifdef CONFIG_SYSCTL
6103 
6104 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6105 		void *buffer, size_t *lenp, loff_t *ppos)
6106 {
6107 	int *valp = ctl->data;
6108 	int val = *valp;
6109 	loff_t pos = *ppos;
6110 	struct ctl_table lctl;
6111 	int ret;
6112 
6113 	/*
6114 	 * ctl->data points to idev->cnf.forwarding, we should
6115 	 * not modify it until we get the rtnl lock.
6116 	 */
6117 	lctl = *ctl;
6118 	lctl.data = &val;
6119 
6120 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6121 
6122 	if (write)
6123 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6124 	if (ret)
6125 		*ppos = pos;
6126 	return ret;
6127 }
6128 
6129 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6130 		void *buffer, size_t *lenp, loff_t *ppos)
6131 {
6132 	struct inet6_dev *idev = ctl->extra1;
6133 	int min_mtu = IPV6_MIN_MTU;
6134 	struct ctl_table lctl;
6135 
6136 	lctl = *ctl;
6137 	lctl.extra1 = &min_mtu;
6138 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6139 
6140 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6141 }
6142 
6143 static void dev_disable_change(struct inet6_dev *idev)
6144 {
6145 	struct netdev_notifier_info info;
6146 
6147 	if (!idev || !idev->dev)
6148 		return;
6149 
6150 	netdev_notifier_info_init(&info, idev->dev);
6151 	if (idev->cnf.disable_ipv6)
6152 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6153 	else
6154 		addrconf_notify(NULL, NETDEV_UP, &info);
6155 }
6156 
6157 static void addrconf_disable_change(struct net *net, __s32 newf)
6158 {
6159 	struct net_device *dev;
6160 	struct inet6_dev *idev;
6161 
6162 	for_each_netdev(net, dev) {
6163 		idev = __in6_dev_get(dev);
6164 		if (idev) {
6165 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6166 			idev->cnf.disable_ipv6 = newf;
6167 			if (changed)
6168 				dev_disable_change(idev);
6169 		}
6170 	}
6171 }
6172 
6173 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6174 {
6175 	struct net *net;
6176 	int old;
6177 
6178 	if (!rtnl_trylock())
6179 		return restart_syscall();
6180 
6181 	net = (struct net *)table->extra2;
6182 	old = *p;
6183 	*p = newf;
6184 
6185 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6186 		rtnl_unlock();
6187 		return 0;
6188 	}
6189 
6190 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6191 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6192 		addrconf_disable_change(net, newf);
6193 	} else if ((!newf) ^ (!old))
6194 		dev_disable_change((struct inet6_dev *)table->extra1);
6195 
6196 	rtnl_unlock();
6197 	return 0;
6198 }
6199 
6200 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6201 		void *buffer, size_t *lenp, loff_t *ppos)
6202 {
6203 	int *valp = ctl->data;
6204 	int val = *valp;
6205 	loff_t pos = *ppos;
6206 	struct ctl_table lctl;
6207 	int ret;
6208 
6209 	/*
6210 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6211 	 * not modify it until we get the rtnl lock.
6212 	 */
6213 	lctl = *ctl;
6214 	lctl.data = &val;
6215 
6216 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6217 
6218 	if (write)
6219 		ret = addrconf_disable_ipv6(ctl, valp, val);
6220 	if (ret)
6221 		*ppos = pos;
6222 	return ret;
6223 }
6224 
6225 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6226 		void *buffer, size_t *lenp, loff_t *ppos)
6227 {
6228 	int *valp = ctl->data;
6229 	int ret;
6230 	int old, new;
6231 
6232 	old = *valp;
6233 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6234 	new = *valp;
6235 
6236 	if (write && old != new) {
6237 		struct net *net = ctl->extra2;
6238 
6239 		if (!rtnl_trylock())
6240 			return restart_syscall();
6241 
6242 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6243 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6244 						     NETCONFA_PROXY_NEIGH,
6245 						     NETCONFA_IFINDEX_DEFAULT,
6246 						     net->ipv6.devconf_dflt);
6247 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6248 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6249 						     NETCONFA_PROXY_NEIGH,
6250 						     NETCONFA_IFINDEX_ALL,
6251 						     net->ipv6.devconf_all);
6252 		else {
6253 			struct inet6_dev *idev = ctl->extra1;
6254 
6255 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6256 						     NETCONFA_PROXY_NEIGH,
6257 						     idev->dev->ifindex,
6258 						     &idev->cnf);
6259 		}
6260 		rtnl_unlock();
6261 	}
6262 
6263 	return ret;
6264 }
6265 
6266 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6267 					 void *buffer, size_t *lenp,
6268 					 loff_t *ppos)
6269 {
6270 	int ret = 0;
6271 	u32 new_val;
6272 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6273 	struct net *net = (struct net *)ctl->extra2;
6274 	struct ctl_table tmp = {
6275 		.data = &new_val,
6276 		.maxlen = sizeof(new_val),
6277 		.mode = ctl->mode,
6278 	};
6279 
6280 	if (!rtnl_trylock())
6281 		return restart_syscall();
6282 
6283 	new_val = *((u32 *)ctl->data);
6284 
6285 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6286 	if (ret != 0)
6287 		goto out;
6288 
6289 	if (write) {
6290 		if (check_addr_gen_mode(new_val) < 0) {
6291 			ret = -EINVAL;
6292 			goto out;
6293 		}
6294 
6295 		if (idev) {
6296 			if (check_stable_privacy(idev, net, new_val) < 0) {
6297 				ret = -EINVAL;
6298 				goto out;
6299 			}
6300 
6301 			if (idev->cnf.addr_gen_mode != new_val) {
6302 				idev->cnf.addr_gen_mode = new_val;
6303 				addrconf_dev_config(idev->dev);
6304 			}
6305 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6306 			struct net_device *dev;
6307 
6308 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6309 			for_each_netdev(net, dev) {
6310 				idev = __in6_dev_get(dev);
6311 				if (idev &&
6312 				    idev->cnf.addr_gen_mode != new_val) {
6313 					idev->cnf.addr_gen_mode = new_val;
6314 					addrconf_dev_config(idev->dev);
6315 				}
6316 			}
6317 		}
6318 
6319 		*((u32 *)ctl->data) = new_val;
6320 	}
6321 
6322 out:
6323 	rtnl_unlock();
6324 
6325 	return ret;
6326 }
6327 
6328 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6329 					 void *buffer, size_t *lenp,
6330 					 loff_t *ppos)
6331 {
6332 	int err;
6333 	struct in6_addr addr;
6334 	char str[IPV6_MAX_STRLEN];
6335 	struct ctl_table lctl = *ctl;
6336 	struct net *net = ctl->extra2;
6337 	struct ipv6_stable_secret *secret = ctl->data;
6338 
6339 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6340 		return -EIO;
6341 
6342 	lctl.maxlen = IPV6_MAX_STRLEN;
6343 	lctl.data = str;
6344 
6345 	if (!rtnl_trylock())
6346 		return restart_syscall();
6347 
6348 	if (!write && !secret->initialized) {
6349 		err = -EIO;
6350 		goto out;
6351 	}
6352 
6353 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6354 	if (err >= sizeof(str)) {
6355 		err = -EIO;
6356 		goto out;
6357 	}
6358 
6359 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6360 	if (err || !write)
6361 		goto out;
6362 
6363 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6364 		err = -EIO;
6365 		goto out;
6366 	}
6367 
6368 	secret->initialized = true;
6369 	secret->secret = addr;
6370 
6371 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6372 		struct net_device *dev;
6373 
6374 		for_each_netdev(net, dev) {
6375 			struct inet6_dev *idev = __in6_dev_get(dev);
6376 
6377 			if (idev) {
6378 				idev->cnf.addr_gen_mode =
6379 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6380 			}
6381 		}
6382 	} else {
6383 		struct inet6_dev *idev = ctl->extra1;
6384 
6385 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6386 	}
6387 
6388 out:
6389 	rtnl_unlock();
6390 
6391 	return err;
6392 }
6393 
6394 static
6395 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6396 						int write, void *buffer,
6397 						size_t *lenp,
6398 						loff_t *ppos)
6399 {
6400 	int *valp = ctl->data;
6401 	int val = *valp;
6402 	loff_t pos = *ppos;
6403 	struct ctl_table lctl;
6404 	int ret;
6405 
6406 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6407 	 * we should not modify it until we get the rtnl lock.
6408 	 */
6409 	lctl = *ctl;
6410 	lctl.data = &val;
6411 
6412 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6413 
6414 	if (write)
6415 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6416 	if (ret)
6417 		*ppos = pos;
6418 	return ret;
6419 }
6420 
6421 static
6422 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6423 {
6424 	if (rt) {
6425 		if (action)
6426 			rt->dst.flags |= DST_NOPOLICY;
6427 		else
6428 			rt->dst.flags &= ~DST_NOPOLICY;
6429 	}
6430 }
6431 
6432 static
6433 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6434 {
6435 	struct inet6_ifaddr *ifa;
6436 
6437 	read_lock_bh(&idev->lock);
6438 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6439 		spin_lock(&ifa->lock);
6440 		if (ifa->rt) {
6441 			/* host routes only use builtin fib6_nh */
6442 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6443 			int cpu;
6444 
6445 			rcu_read_lock();
6446 			ifa->rt->dst_nopolicy = val ? true : false;
6447 			if (nh->rt6i_pcpu) {
6448 				for_each_possible_cpu(cpu) {
6449 					struct rt6_info **rtp;
6450 
6451 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6452 					addrconf_set_nopolicy(*rtp, val);
6453 				}
6454 			}
6455 			rcu_read_unlock();
6456 		}
6457 		spin_unlock(&ifa->lock);
6458 	}
6459 	read_unlock_bh(&idev->lock);
6460 }
6461 
6462 static
6463 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6464 {
6465 	struct inet6_dev *idev;
6466 	struct net *net;
6467 
6468 	if (!rtnl_trylock())
6469 		return restart_syscall();
6470 
6471 	*valp = val;
6472 
6473 	net = (struct net *)ctl->extra2;
6474 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6475 		rtnl_unlock();
6476 		return 0;
6477 	}
6478 
6479 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6480 		struct net_device *dev;
6481 
6482 		for_each_netdev(net, dev) {
6483 			idev = __in6_dev_get(dev);
6484 			if (idev)
6485 				addrconf_disable_policy_idev(idev, val);
6486 		}
6487 	} else {
6488 		idev = (struct inet6_dev *)ctl->extra1;
6489 		addrconf_disable_policy_idev(idev, val);
6490 	}
6491 
6492 	rtnl_unlock();
6493 	return 0;
6494 }
6495 
6496 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6497 				   void *buffer, size_t *lenp, loff_t *ppos)
6498 {
6499 	int *valp = ctl->data;
6500 	int val = *valp;
6501 	loff_t pos = *ppos;
6502 	struct ctl_table lctl;
6503 	int ret;
6504 
6505 	lctl = *ctl;
6506 	lctl.data = &val;
6507 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6508 
6509 	if (write && (*valp != val))
6510 		ret = addrconf_disable_policy(ctl, valp, val);
6511 
6512 	if (ret)
6513 		*ppos = pos;
6514 
6515 	return ret;
6516 }
6517 
6518 static int minus_one = -1;
6519 static const int two_five_five = 255;
6520 
6521 static const struct ctl_table addrconf_sysctl[] = {
6522 	{
6523 		.procname	= "forwarding",
6524 		.data		= &ipv6_devconf.forwarding,
6525 		.maxlen		= sizeof(int),
6526 		.mode		= 0644,
6527 		.proc_handler	= addrconf_sysctl_forward,
6528 	},
6529 	{
6530 		.procname	= "hop_limit",
6531 		.data		= &ipv6_devconf.hop_limit,
6532 		.maxlen		= sizeof(int),
6533 		.mode		= 0644,
6534 		.proc_handler	= proc_dointvec_minmax,
6535 		.extra1		= (void *)SYSCTL_ONE,
6536 		.extra2		= (void *)&two_five_five,
6537 	},
6538 	{
6539 		.procname	= "mtu",
6540 		.data		= &ipv6_devconf.mtu6,
6541 		.maxlen		= sizeof(int),
6542 		.mode		= 0644,
6543 		.proc_handler	= addrconf_sysctl_mtu,
6544 	},
6545 	{
6546 		.procname	= "accept_ra",
6547 		.data		= &ipv6_devconf.accept_ra,
6548 		.maxlen		= sizeof(int),
6549 		.mode		= 0644,
6550 		.proc_handler	= proc_dointvec,
6551 	},
6552 	{
6553 		.procname	= "accept_redirects",
6554 		.data		= &ipv6_devconf.accept_redirects,
6555 		.maxlen		= sizeof(int),
6556 		.mode		= 0644,
6557 		.proc_handler	= proc_dointvec,
6558 	},
6559 	{
6560 		.procname	= "autoconf",
6561 		.data		= &ipv6_devconf.autoconf,
6562 		.maxlen		= sizeof(int),
6563 		.mode		= 0644,
6564 		.proc_handler	= proc_dointvec,
6565 	},
6566 	{
6567 		.procname	= "dad_transmits",
6568 		.data		= &ipv6_devconf.dad_transmits,
6569 		.maxlen		= sizeof(int),
6570 		.mode		= 0644,
6571 		.proc_handler	= proc_dointvec,
6572 	},
6573 	{
6574 		.procname	= "router_solicitations",
6575 		.data		= &ipv6_devconf.rtr_solicits,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec_minmax,
6579 		.extra1		= &minus_one,
6580 	},
6581 	{
6582 		.procname	= "router_solicitation_interval",
6583 		.data		= &ipv6_devconf.rtr_solicit_interval,
6584 		.maxlen		= sizeof(int),
6585 		.mode		= 0644,
6586 		.proc_handler	= proc_dointvec_jiffies,
6587 	},
6588 	{
6589 		.procname	= "router_solicitation_max_interval",
6590 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6591 		.maxlen		= sizeof(int),
6592 		.mode		= 0644,
6593 		.proc_handler	= proc_dointvec_jiffies,
6594 	},
6595 	{
6596 		.procname	= "router_solicitation_delay",
6597 		.data		= &ipv6_devconf.rtr_solicit_delay,
6598 		.maxlen		= sizeof(int),
6599 		.mode		= 0644,
6600 		.proc_handler	= proc_dointvec_jiffies,
6601 	},
6602 	{
6603 		.procname	= "force_mld_version",
6604 		.data		= &ipv6_devconf.force_mld_version,
6605 		.maxlen		= sizeof(int),
6606 		.mode		= 0644,
6607 		.proc_handler	= proc_dointvec,
6608 	},
6609 	{
6610 		.procname	= "mldv1_unsolicited_report_interval",
6611 		.data		=
6612 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6613 		.maxlen		= sizeof(int),
6614 		.mode		= 0644,
6615 		.proc_handler	= proc_dointvec_ms_jiffies,
6616 	},
6617 	{
6618 		.procname	= "mldv2_unsolicited_report_interval",
6619 		.data		=
6620 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6621 		.maxlen		= sizeof(int),
6622 		.mode		= 0644,
6623 		.proc_handler	= proc_dointvec_ms_jiffies,
6624 	},
6625 	{
6626 		.procname	= "use_tempaddr",
6627 		.data		= &ipv6_devconf.use_tempaddr,
6628 		.maxlen		= sizeof(int),
6629 		.mode		= 0644,
6630 		.proc_handler	= proc_dointvec,
6631 	},
6632 	{
6633 		.procname	= "temp_valid_lft",
6634 		.data		= &ipv6_devconf.temp_valid_lft,
6635 		.maxlen		= sizeof(int),
6636 		.mode		= 0644,
6637 		.proc_handler	= proc_dointvec,
6638 	},
6639 	{
6640 		.procname	= "temp_prefered_lft",
6641 		.data		= &ipv6_devconf.temp_prefered_lft,
6642 		.maxlen		= sizeof(int),
6643 		.mode		= 0644,
6644 		.proc_handler	= proc_dointvec,
6645 	},
6646 	{
6647 		.procname	= "regen_max_retry",
6648 		.data		= &ipv6_devconf.regen_max_retry,
6649 		.maxlen		= sizeof(int),
6650 		.mode		= 0644,
6651 		.proc_handler	= proc_dointvec,
6652 	},
6653 	{
6654 		.procname	= "max_desync_factor",
6655 		.data		= &ipv6_devconf.max_desync_factor,
6656 		.maxlen		= sizeof(int),
6657 		.mode		= 0644,
6658 		.proc_handler	= proc_dointvec,
6659 	},
6660 	{
6661 		.procname	= "max_addresses",
6662 		.data		= &ipv6_devconf.max_addresses,
6663 		.maxlen		= sizeof(int),
6664 		.mode		= 0644,
6665 		.proc_handler	= proc_dointvec,
6666 	},
6667 	{
6668 		.procname	= "accept_ra_defrtr",
6669 		.data		= &ipv6_devconf.accept_ra_defrtr,
6670 		.maxlen		= sizeof(int),
6671 		.mode		= 0644,
6672 		.proc_handler	= proc_dointvec,
6673 	},
6674 	{
6675 		.procname	= "ra_defrtr_metric",
6676 		.data		= &ipv6_devconf.ra_defrtr_metric,
6677 		.maxlen		= sizeof(u32),
6678 		.mode		= 0644,
6679 		.proc_handler	= proc_douintvec_minmax,
6680 		.extra1		= (void *)SYSCTL_ONE,
6681 	},
6682 	{
6683 		.procname	= "accept_ra_min_hop_limit",
6684 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6685 		.maxlen		= sizeof(int),
6686 		.mode		= 0644,
6687 		.proc_handler	= proc_dointvec,
6688 	},
6689 	{
6690 		.procname	= "accept_ra_pinfo",
6691 		.data		= &ipv6_devconf.accept_ra_pinfo,
6692 		.maxlen		= sizeof(int),
6693 		.mode		= 0644,
6694 		.proc_handler	= proc_dointvec,
6695 	},
6696 #ifdef CONFIG_IPV6_ROUTER_PREF
6697 	{
6698 		.procname	= "accept_ra_rtr_pref",
6699 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6700 		.maxlen		= sizeof(int),
6701 		.mode		= 0644,
6702 		.proc_handler	= proc_dointvec,
6703 	},
6704 	{
6705 		.procname	= "router_probe_interval",
6706 		.data		= &ipv6_devconf.rtr_probe_interval,
6707 		.maxlen		= sizeof(int),
6708 		.mode		= 0644,
6709 		.proc_handler	= proc_dointvec_jiffies,
6710 	},
6711 #ifdef CONFIG_IPV6_ROUTE_INFO
6712 	{
6713 		.procname	= "accept_ra_rt_info_min_plen",
6714 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6715 		.maxlen		= sizeof(int),
6716 		.mode		= 0644,
6717 		.proc_handler	= proc_dointvec,
6718 	},
6719 	{
6720 		.procname	= "accept_ra_rt_info_max_plen",
6721 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6722 		.maxlen		= sizeof(int),
6723 		.mode		= 0644,
6724 		.proc_handler	= proc_dointvec,
6725 	},
6726 #endif
6727 #endif
6728 	{
6729 		.procname	= "proxy_ndp",
6730 		.data		= &ipv6_devconf.proxy_ndp,
6731 		.maxlen		= sizeof(int),
6732 		.mode		= 0644,
6733 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6734 	},
6735 	{
6736 		.procname	= "accept_source_route",
6737 		.data		= &ipv6_devconf.accept_source_route,
6738 		.maxlen		= sizeof(int),
6739 		.mode		= 0644,
6740 		.proc_handler	= proc_dointvec,
6741 	},
6742 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6743 	{
6744 		.procname	= "optimistic_dad",
6745 		.data		= &ipv6_devconf.optimistic_dad,
6746 		.maxlen		= sizeof(int),
6747 		.mode		= 0644,
6748 		.proc_handler   = proc_dointvec,
6749 	},
6750 	{
6751 		.procname	= "use_optimistic",
6752 		.data		= &ipv6_devconf.use_optimistic,
6753 		.maxlen		= sizeof(int),
6754 		.mode		= 0644,
6755 		.proc_handler	= proc_dointvec,
6756 	},
6757 #endif
6758 #ifdef CONFIG_IPV6_MROUTE
6759 	{
6760 		.procname	= "mc_forwarding",
6761 		.data		= &ipv6_devconf.mc_forwarding,
6762 		.maxlen		= sizeof(int),
6763 		.mode		= 0444,
6764 		.proc_handler	= proc_dointvec,
6765 	},
6766 #endif
6767 	{
6768 		.procname	= "disable_ipv6",
6769 		.data		= &ipv6_devconf.disable_ipv6,
6770 		.maxlen		= sizeof(int),
6771 		.mode		= 0644,
6772 		.proc_handler	= addrconf_sysctl_disable,
6773 	},
6774 	{
6775 		.procname	= "accept_dad",
6776 		.data		= &ipv6_devconf.accept_dad,
6777 		.maxlen		= sizeof(int),
6778 		.mode		= 0644,
6779 		.proc_handler	= proc_dointvec,
6780 	},
6781 	{
6782 		.procname	= "force_tllao",
6783 		.data		= &ipv6_devconf.force_tllao,
6784 		.maxlen		= sizeof(int),
6785 		.mode		= 0644,
6786 		.proc_handler	= proc_dointvec
6787 	},
6788 	{
6789 		.procname	= "ndisc_notify",
6790 		.data		= &ipv6_devconf.ndisc_notify,
6791 		.maxlen		= sizeof(int),
6792 		.mode		= 0644,
6793 		.proc_handler	= proc_dointvec
6794 	},
6795 	{
6796 		.procname	= "suppress_frag_ndisc",
6797 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6798 		.maxlen		= sizeof(int),
6799 		.mode		= 0644,
6800 		.proc_handler	= proc_dointvec
6801 	},
6802 	{
6803 		.procname	= "accept_ra_from_local",
6804 		.data		= &ipv6_devconf.accept_ra_from_local,
6805 		.maxlen		= sizeof(int),
6806 		.mode		= 0644,
6807 		.proc_handler	= proc_dointvec,
6808 	},
6809 	{
6810 		.procname	= "accept_ra_mtu",
6811 		.data		= &ipv6_devconf.accept_ra_mtu,
6812 		.maxlen		= sizeof(int),
6813 		.mode		= 0644,
6814 		.proc_handler	= proc_dointvec,
6815 	},
6816 	{
6817 		.procname	= "stable_secret",
6818 		.data		= &ipv6_devconf.stable_secret,
6819 		.maxlen		= IPV6_MAX_STRLEN,
6820 		.mode		= 0600,
6821 		.proc_handler	= addrconf_sysctl_stable_secret,
6822 	},
6823 	{
6824 		.procname	= "use_oif_addrs_only",
6825 		.data		= &ipv6_devconf.use_oif_addrs_only,
6826 		.maxlen		= sizeof(int),
6827 		.mode		= 0644,
6828 		.proc_handler	= proc_dointvec,
6829 	},
6830 	{
6831 		.procname	= "ignore_routes_with_linkdown",
6832 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6833 		.maxlen		= sizeof(int),
6834 		.mode		= 0644,
6835 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6836 	},
6837 	{
6838 		.procname	= "drop_unicast_in_l2_multicast",
6839 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6840 		.maxlen		= sizeof(int),
6841 		.mode		= 0644,
6842 		.proc_handler	= proc_dointvec,
6843 	},
6844 	{
6845 		.procname	= "drop_unsolicited_na",
6846 		.data		= &ipv6_devconf.drop_unsolicited_na,
6847 		.maxlen		= sizeof(int),
6848 		.mode		= 0644,
6849 		.proc_handler	= proc_dointvec,
6850 	},
6851 	{
6852 		.procname	= "keep_addr_on_down",
6853 		.data		= &ipv6_devconf.keep_addr_on_down,
6854 		.maxlen		= sizeof(int),
6855 		.mode		= 0644,
6856 		.proc_handler	= proc_dointvec,
6857 
6858 	},
6859 	{
6860 		.procname	= "seg6_enabled",
6861 		.data		= &ipv6_devconf.seg6_enabled,
6862 		.maxlen		= sizeof(int),
6863 		.mode		= 0644,
6864 		.proc_handler	= proc_dointvec,
6865 	},
6866 #ifdef CONFIG_IPV6_SEG6_HMAC
6867 	{
6868 		.procname	= "seg6_require_hmac",
6869 		.data		= &ipv6_devconf.seg6_require_hmac,
6870 		.maxlen		= sizeof(int),
6871 		.mode		= 0644,
6872 		.proc_handler	= proc_dointvec,
6873 	},
6874 #endif
6875 	{
6876 		.procname       = "enhanced_dad",
6877 		.data           = &ipv6_devconf.enhanced_dad,
6878 		.maxlen         = sizeof(int),
6879 		.mode           = 0644,
6880 		.proc_handler   = proc_dointvec,
6881 	},
6882 	{
6883 		.procname		= "addr_gen_mode",
6884 		.data			= &ipv6_devconf.addr_gen_mode,
6885 		.maxlen			= sizeof(int),
6886 		.mode			= 0644,
6887 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6888 	},
6889 	{
6890 		.procname       = "disable_policy",
6891 		.data           = &ipv6_devconf.disable_policy,
6892 		.maxlen         = sizeof(int),
6893 		.mode           = 0644,
6894 		.proc_handler   = addrconf_sysctl_disable_policy,
6895 	},
6896 	{
6897 		.procname	= "ndisc_tclass",
6898 		.data		= &ipv6_devconf.ndisc_tclass,
6899 		.maxlen		= sizeof(int),
6900 		.mode		= 0644,
6901 		.proc_handler	= proc_dointvec_minmax,
6902 		.extra1		= (void *)SYSCTL_ZERO,
6903 		.extra2		= (void *)&two_five_five,
6904 	},
6905 	{
6906 		.procname	= "rpl_seg_enabled",
6907 		.data		= &ipv6_devconf.rpl_seg_enabled,
6908 		.maxlen		= sizeof(int),
6909 		.mode		= 0644,
6910 		.proc_handler	= proc_dointvec,
6911 	},
6912 	{
6913 		/* sentinel */
6914 	}
6915 };
6916 
6917 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6918 		struct inet6_dev *idev, struct ipv6_devconf *p)
6919 {
6920 	int i, ifindex;
6921 	struct ctl_table *table;
6922 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6923 
6924 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6925 	if (!table)
6926 		goto out;
6927 
6928 	for (i = 0; table[i].data; i++) {
6929 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6930 		/* If one of these is already set, then it is not safe to
6931 		 * overwrite either of them: this makes proc_dointvec_minmax
6932 		 * usable.
6933 		 */
6934 		if (!table[i].extra1 && !table[i].extra2) {
6935 			table[i].extra1 = idev; /* embedded; no ref */
6936 			table[i].extra2 = net;
6937 		}
6938 	}
6939 
6940 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6941 
6942 	p->sysctl_header = register_net_sysctl(net, path, table);
6943 	if (!p->sysctl_header)
6944 		goto free;
6945 
6946 	if (!strcmp(dev_name, "all"))
6947 		ifindex = NETCONFA_IFINDEX_ALL;
6948 	else if (!strcmp(dev_name, "default"))
6949 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6950 	else
6951 		ifindex = idev->dev->ifindex;
6952 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6953 				     ifindex, p);
6954 	return 0;
6955 
6956 free:
6957 	kfree(table);
6958 out:
6959 	return -ENOBUFS;
6960 }
6961 
6962 static void __addrconf_sysctl_unregister(struct net *net,
6963 					 struct ipv6_devconf *p, int ifindex)
6964 {
6965 	struct ctl_table *table;
6966 
6967 	if (!p->sysctl_header)
6968 		return;
6969 
6970 	table = p->sysctl_header->ctl_table_arg;
6971 	unregister_net_sysctl_table(p->sysctl_header);
6972 	p->sysctl_header = NULL;
6973 	kfree(table);
6974 
6975 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6976 }
6977 
6978 static int addrconf_sysctl_register(struct inet6_dev *idev)
6979 {
6980 	int err;
6981 
6982 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6983 		return -EINVAL;
6984 
6985 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6986 				    &ndisc_ifinfo_sysctl_change);
6987 	if (err)
6988 		return err;
6989 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6990 					 idev, &idev->cnf);
6991 	if (err)
6992 		neigh_sysctl_unregister(idev->nd_parms);
6993 
6994 	return err;
6995 }
6996 
6997 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6998 {
6999 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7000 				     idev->dev->ifindex);
7001 	neigh_sysctl_unregister(idev->nd_parms);
7002 }
7003 
7004 
7005 #endif
7006 
7007 static int __net_init addrconf_init_net(struct net *net)
7008 {
7009 	int err = -ENOMEM;
7010 	struct ipv6_devconf *all, *dflt;
7011 
7012 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7013 	if (!all)
7014 		goto err_alloc_all;
7015 
7016 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7017 	if (!dflt)
7018 		goto err_alloc_dflt;
7019 
7020 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7021 	    !net_eq(net, &init_net)) {
7022 		switch (sysctl_devconf_inherit_init_net) {
7023 		case 1:  /* copy from init_net */
7024 			memcpy(all, init_net.ipv6.devconf_all,
7025 			       sizeof(ipv6_devconf));
7026 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7027 			       sizeof(ipv6_devconf_dflt));
7028 			break;
7029 		case 3: /* copy from the current netns */
7030 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7031 			       sizeof(ipv6_devconf));
7032 			memcpy(dflt,
7033 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7034 			       sizeof(ipv6_devconf_dflt));
7035 			break;
7036 		case 0:
7037 		case 2:
7038 			/* use compiled values */
7039 			break;
7040 		}
7041 	}
7042 
7043 	/* these will be inherited by all namespaces */
7044 	dflt->autoconf = ipv6_defaults.autoconf;
7045 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7046 
7047 	dflt->stable_secret.initialized = false;
7048 	all->stable_secret.initialized = false;
7049 
7050 	net->ipv6.devconf_all = all;
7051 	net->ipv6.devconf_dflt = dflt;
7052 
7053 #ifdef CONFIG_SYSCTL
7054 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7055 	if (err < 0)
7056 		goto err_reg_all;
7057 
7058 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7059 	if (err < 0)
7060 		goto err_reg_dflt;
7061 #endif
7062 	return 0;
7063 
7064 #ifdef CONFIG_SYSCTL
7065 err_reg_dflt:
7066 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7067 err_reg_all:
7068 	kfree(dflt);
7069 #endif
7070 err_alloc_dflt:
7071 	kfree(all);
7072 err_alloc_all:
7073 	return err;
7074 }
7075 
7076 static void __net_exit addrconf_exit_net(struct net *net)
7077 {
7078 #ifdef CONFIG_SYSCTL
7079 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7080 				     NETCONFA_IFINDEX_DEFAULT);
7081 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7082 				     NETCONFA_IFINDEX_ALL);
7083 #endif
7084 	kfree(net->ipv6.devconf_dflt);
7085 	kfree(net->ipv6.devconf_all);
7086 }
7087 
7088 static struct pernet_operations addrconf_ops = {
7089 	.init = addrconf_init_net,
7090 	.exit = addrconf_exit_net,
7091 };
7092 
7093 static struct rtnl_af_ops inet6_ops __read_mostly = {
7094 	.family		  = AF_INET6,
7095 	.fill_link_af	  = inet6_fill_link_af,
7096 	.get_link_af_size = inet6_get_link_af_size,
7097 	.validate_link_af = inet6_validate_link_af,
7098 	.set_link_af	  = inet6_set_link_af,
7099 };
7100 
7101 /*
7102  *	Init / cleanup code
7103  */
7104 
7105 int __init addrconf_init(void)
7106 {
7107 	struct inet6_dev *idev;
7108 	int i, err;
7109 
7110 	err = ipv6_addr_label_init();
7111 	if (err < 0) {
7112 		pr_crit("%s: cannot initialize default policy table: %d\n",
7113 			__func__, err);
7114 		goto out;
7115 	}
7116 
7117 	err = register_pernet_subsys(&addrconf_ops);
7118 	if (err < 0)
7119 		goto out_addrlabel;
7120 
7121 	addrconf_wq = create_workqueue("ipv6_addrconf");
7122 	if (!addrconf_wq) {
7123 		err = -ENOMEM;
7124 		goto out_nowq;
7125 	}
7126 
7127 	/* The addrconf netdev notifier requires that loopback_dev
7128 	 * has it's ipv6 private information allocated and setup
7129 	 * before it can bring up and give link-local addresses
7130 	 * to other devices which are up.
7131 	 *
7132 	 * Unfortunately, loopback_dev is not necessarily the first
7133 	 * entry in the global dev_base list of net devices.  In fact,
7134 	 * it is likely to be the very last entry on that list.
7135 	 * So this causes the notifier registry below to try and
7136 	 * give link-local addresses to all devices besides loopback_dev
7137 	 * first, then loopback_dev, which cases all the non-loopback_dev
7138 	 * devices to fail to get a link-local address.
7139 	 *
7140 	 * So, as a temporary fix, allocate the ipv6 structure for
7141 	 * loopback_dev first by hand.
7142 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7143 	 * device and it being up should be removed.
7144 	 */
7145 	rtnl_lock();
7146 	idev = ipv6_add_dev(init_net.loopback_dev);
7147 	rtnl_unlock();
7148 	if (IS_ERR(idev)) {
7149 		err = PTR_ERR(idev);
7150 		goto errlo;
7151 	}
7152 
7153 	ip6_route_init_special_entries();
7154 
7155 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7156 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7157 
7158 	register_netdevice_notifier(&ipv6_dev_notf);
7159 
7160 	addrconf_verify();
7161 
7162 	rtnl_af_register(&inet6_ops);
7163 
7164 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7165 				   NULL, inet6_dump_ifinfo, 0);
7166 	if (err < 0)
7167 		goto errout;
7168 
7169 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7170 				   inet6_rtm_newaddr, NULL, 0);
7171 	if (err < 0)
7172 		goto errout;
7173 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7174 				   inet6_rtm_deladdr, NULL, 0);
7175 	if (err < 0)
7176 		goto errout;
7177 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7178 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7179 				   RTNL_FLAG_DOIT_UNLOCKED);
7180 	if (err < 0)
7181 		goto errout;
7182 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7183 				   NULL, inet6_dump_ifmcaddr, 0);
7184 	if (err < 0)
7185 		goto errout;
7186 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7187 				   NULL, inet6_dump_ifacaddr, 0);
7188 	if (err < 0)
7189 		goto errout;
7190 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7191 				   inet6_netconf_get_devconf,
7192 				   inet6_netconf_dump_devconf,
7193 				   RTNL_FLAG_DOIT_UNLOCKED);
7194 	if (err < 0)
7195 		goto errout;
7196 	err = ipv6_addr_label_rtnl_register();
7197 	if (err < 0)
7198 		goto errout;
7199 
7200 	return 0;
7201 errout:
7202 	rtnl_unregister_all(PF_INET6);
7203 	rtnl_af_unregister(&inet6_ops);
7204 	unregister_netdevice_notifier(&ipv6_dev_notf);
7205 errlo:
7206 	destroy_workqueue(addrconf_wq);
7207 out_nowq:
7208 	unregister_pernet_subsys(&addrconf_ops);
7209 out_addrlabel:
7210 	ipv6_addr_label_cleanup();
7211 out:
7212 	return err;
7213 }
7214 
7215 void addrconf_cleanup(void)
7216 {
7217 	struct net_device *dev;
7218 	int i;
7219 
7220 	unregister_netdevice_notifier(&ipv6_dev_notf);
7221 	unregister_pernet_subsys(&addrconf_ops);
7222 	ipv6_addr_label_cleanup();
7223 
7224 	rtnl_af_unregister(&inet6_ops);
7225 
7226 	rtnl_lock();
7227 
7228 	/* clean dev list */
7229 	for_each_netdev(&init_net, dev) {
7230 		if (__in6_dev_get(dev) == NULL)
7231 			continue;
7232 		addrconf_ifdown(dev, true);
7233 	}
7234 	addrconf_ifdown(init_net.loopback_dev, true);
7235 
7236 	/*
7237 	 *	Check hash table.
7238 	 */
7239 	spin_lock_bh(&addrconf_hash_lock);
7240 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7241 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7242 	spin_unlock_bh(&addrconf_hash_lock);
7243 	cancel_delayed_work(&addr_chk_work);
7244 	rtnl_unlock();
7245 
7246 	destroy_workqueue(addrconf_wq);
7247 }
7248