xref: /openbmc/linux/net/ipv6/addrconf.c (revision d0676871)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_regen_rndid(struct inet6_dev *idev);
139 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 /*
150  *	Configured unicast address hash table
151  */
152 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
153 static DEFINE_SPINLOCK(addrconf_hash_lock);
154 
155 static void addrconf_verify(void);
156 static void addrconf_verify_rtnl(void);
157 static void addrconf_verify_work(struct work_struct *);
158 
159 static struct workqueue_struct *addrconf_wq;
160 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
161 
162 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
163 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
164 
165 static void addrconf_type_change(struct net_device *dev,
166 				 unsigned long event);
167 static int addrconf_ifdown(struct net_device *dev, int how);
168 
169 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
170 						  int plen,
171 						  const struct net_device *dev,
172 						  u32 flags, u32 noflags,
173 						  bool no_gw);
174 
175 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
176 static void addrconf_dad_work(struct work_struct *w);
177 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
178 				   bool send_na);
179 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
180 static void addrconf_rs_timer(struct timer_list *t);
181 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
183 
184 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
185 				struct prefix_info *pinfo);
186 
187 static struct ipv6_devconf ipv6_devconf __read_mostly = {
188 	.forwarding		= 0,
189 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
190 	.mtu6			= IPV6_MIN_MTU,
191 	.accept_ra		= 1,
192 	.accept_redirects	= 1,
193 	.autoconf		= 1,
194 	.force_mld_version	= 0,
195 	.mldv1_unsolicited_report_interval = 10 * HZ,
196 	.mldv2_unsolicited_report_interval = HZ,
197 	.dad_transmits		= 1,
198 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
199 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
200 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
201 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
202 	.use_tempaddr		= 0,
203 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
204 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
205 	.regen_max_retry	= REGEN_MAX_RETRY,
206 	.max_desync_factor	= MAX_DESYNC_FACTOR,
207 	.max_addresses		= IPV6_MAX_ADDRESSES,
208 	.accept_ra_defrtr	= 1,
209 	.accept_ra_from_local	= 0,
210 	.accept_ra_min_hop_limit= 1,
211 	.accept_ra_pinfo	= 1,
212 #ifdef CONFIG_IPV6_ROUTER_PREF
213 	.accept_ra_rtr_pref	= 1,
214 	.rtr_probe_interval	= 60 * HZ,
215 #ifdef CONFIG_IPV6_ROUTE_INFO
216 	.accept_ra_rt_info_min_plen = 0,
217 	.accept_ra_rt_info_max_plen = 0,
218 #endif
219 #endif
220 	.proxy_ndp		= 0,
221 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
222 	.disable_ipv6		= 0,
223 	.accept_dad		= 0,
224 	.suppress_frag_ndisc	= 1,
225 	.accept_ra_mtu		= 1,
226 	.stable_secret		= {
227 		.initialized = false,
228 	},
229 	.use_oif_addrs_only	= 0,
230 	.ignore_routes_with_linkdown = 0,
231 	.keep_addr_on_down	= 0,
232 	.seg6_enabled		= 0,
233 #ifdef CONFIG_IPV6_SEG6_HMAC
234 	.seg6_require_hmac	= 0,
235 #endif
236 	.enhanced_dad           = 1,
237 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
238 	.disable_policy		= 0,
239 	.rpl_seg_enabled	= 0,
240 };
241 
242 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
243 	.forwarding		= 0,
244 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
245 	.mtu6			= IPV6_MIN_MTU,
246 	.accept_ra		= 1,
247 	.accept_redirects	= 1,
248 	.autoconf		= 1,
249 	.force_mld_version	= 0,
250 	.mldv1_unsolicited_report_interval = 10 * HZ,
251 	.mldv2_unsolicited_report_interval = HZ,
252 	.dad_transmits		= 1,
253 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
254 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
255 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
256 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
257 	.use_tempaddr		= 0,
258 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
259 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
260 	.regen_max_retry	= REGEN_MAX_RETRY,
261 	.max_desync_factor	= MAX_DESYNC_FACTOR,
262 	.max_addresses		= IPV6_MAX_ADDRESSES,
263 	.accept_ra_defrtr	= 1,
264 	.accept_ra_from_local	= 0,
265 	.accept_ra_min_hop_limit= 1,
266 	.accept_ra_pinfo	= 1,
267 #ifdef CONFIG_IPV6_ROUTER_PREF
268 	.accept_ra_rtr_pref	= 1,
269 	.rtr_probe_interval	= 60 * HZ,
270 #ifdef CONFIG_IPV6_ROUTE_INFO
271 	.accept_ra_rt_info_min_plen = 0,
272 	.accept_ra_rt_info_max_plen = 0,
273 #endif
274 #endif
275 	.proxy_ndp		= 0,
276 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
277 	.disable_ipv6		= 0,
278 	.accept_dad		= 1,
279 	.suppress_frag_ndisc	= 1,
280 	.accept_ra_mtu		= 1,
281 	.stable_secret		= {
282 		.initialized = false,
283 	},
284 	.use_oif_addrs_only	= 0,
285 	.ignore_routes_with_linkdown = 0,
286 	.keep_addr_on_down	= 0,
287 	.seg6_enabled		= 0,
288 #ifdef CONFIG_IPV6_SEG6_HMAC
289 	.seg6_require_hmac	= 0,
290 #endif
291 	.enhanced_dad           = 1,
292 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
293 	.disable_policy		= 0,
294 	.rpl_seg_enabled	= 0,
295 };
296 
297 /* Check if link is ready: is it up and is a valid qdisc available */
298 static inline bool addrconf_link_ready(const struct net_device *dev)
299 {
300 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
301 }
302 
303 static void addrconf_del_rs_timer(struct inet6_dev *idev)
304 {
305 	if (del_timer(&idev->rs_timer))
306 		__in6_dev_put(idev);
307 }
308 
309 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
310 {
311 	if (cancel_delayed_work(&ifp->dad_work))
312 		__in6_ifa_put(ifp);
313 }
314 
315 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
316 				  unsigned long when)
317 {
318 	if (!timer_pending(&idev->rs_timer))
319 		in6_dev_hold(idev);
320 	mod_timer(&idev->rs_timer, jiffies + when);
321 }
322 
323 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
324 				   unsigned long delay)
325 {
326 	in6_ifa_hold(ifp);
327 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
328 		in6_ifa_put(ifp);
329 }
330 
331 static int snmp6_alloc_dev(struct inet6_dev *idev)
332 {
333 	int i;
334 
335 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
336 	if (!idev->stats.ipv6)
337 		goto err_ip;
338 
339 	for_each_possible_cpu(i) {
340 		struct ipstats_mib *addrconf_stats;
341 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
342 		u64_stats_init(&addrconf_stats->syncp);
343 	}
344 
345 
346 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
347 					GFP_KERNEL);
348 	if (!idev->stats.icmpv6dev)
349 		goto err_icmp;
350 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
351 					   GFP_KERNEL);
352 	if (!idev->stats.icmpv6msgdev)
353 		goto err_icmpmsg;
354 
355 	return 0;
356 
357 err_icmpmsg:
358 	kfree(idev->stats.icmpv6dev);
359 err_icmp:
360 	free_percpu(idev->stats.ipv6);
361 err_ip:
362 	return -ENOMEM;
363 }
364 
365 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
366 {
367 	struct inet6_dev *ndev;
368 	int err = -ENOMEM;
369 
370 	ASSERT_RTNL();
371 
372 	if (dev->mtu < IPV6_MIN_MTU)
373 		return ERR_PTR(-EINVAL);
374 
375 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
376 	if (!ndev)
377 		return ERR_PTR(err);
378 
379 	rwlock_init(&ndev->lock);
380 	ndev->dev = dev;
381 	INIT_LIST_HEAD(&ndev->addr_list);
382 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
383 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
384 
385 	if (ndev->cnf.stable_secret.initialized)
386 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
387 
388 	ndev->cnf.mtu6 = dev->mtu;
389 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
390 	if (!ndev->nd_parms) {
391 		kfree(ndev);
392 		return ERR_PTR(err);
393 	}
394 	if (ndev->cnf.forwarding)
395 		dev_disable_lro(dev);
396 	/* We refer to the device */
397 	dev_hold(dev);
398 
399 	if (snmp6_alloc_dev(ndev) < 0) {
400 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
401 			   __func__);
402 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
403 		dev_put(dev);
404 		kfree(ndev);
405 		return ERR_PTR(err);
406 	}
407 
408 	if (snmp6_register_dev(ndev) < 0) {
409 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
410 			   __func__, dev->name);
411 		goto err_release;
412 	}
413 
414 	/* One reference from device. */
415 	refcount_set(&ndev->refcnt, 1);
416 
417 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
418 		ndev->cnf.accept_dad = -1;
419 
420 #if IS_ENABLED(CONFIG_IPV6_SIT)
421 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
422 		pr_info("%s: Disabled Multicast RS\n", dev->name);
423 		ndev->cnf.rtr_solicits = 0;
424 	}
425 #endif
426 
427 	INIT_LIST_HEAD(&ndev->tempaddr_list);
428 	ndev->desync_factor = U32_MAX;
429 	if ((dev->flags&IFF_LOOPBACK) ||
430 	    dev->type == ARPHRD_TUNNEL ||
431 	    dev->type == ARPHRD_TUNNEL6 ||
432 	    dev->type == ARPHRD_SIT ||
433 	    dev->type == ARPHRD_NONE) {
434 		ndev->cnf.use_tempaddr = -1;
435 	} else
436 		ipv6_regen_rndid(ndev);
437 
438 	ndev->token = in6addr_any;
439 
440 	if (netif_running(dev) && addrconf_link_ready(dev))
441 		ndev->if_flags |= IF_READY;
442 
443 	ipv6_mc_init_dev(ndev);
444 	ndev->tstamp = jiffies;
445 	err = addrconf_sysctl_register(ndev);
446 	if (err) {
447 		ipv6_mc_destroy_dev(ndev);
448 		snmp6_unregister_dev(ndev);
449 		goto err_release;
450 	}
451 	/* protected by rtnl_lock */
452 	rcu_assign_pointer(dev->ip6_ptr, ndev);
453 
454 	/* Join interface-local all-node multicast group */
455 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
456 
457 	/* Join all-node multicast group */
458 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
459 
460 	/* Join all-router multicast group if forwarding is set */
461 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
462 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
463 
464 	return ndev;
465 
466 err_release:
467 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
468 	ndev->dead = 1;
469 	in6_dev_finish_destroy(ndev);
470 	return ERR_PTR(err);
471 }
472 
473 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
474 {
475 	struct inet6_dev *idev;
476 
477 	ASSERT_RTNL();
478 
479 	idev = __in6_dev_get(dev);
480 	if (!idev) {
481 		idev = ipv6_add_dev(dev);
482 		if (IS_ERR(idev))
483 			return idev;
484 	}
485 
486 	if (dev->flags&IFF_UP)
487 		ipv6_mc_up(idev);
488 	return idev;
489 }
490 
491 static int inet6_netconf_msgsize_devconf(int type)
492 {
493 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
494 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
495 	bool all = false;
496 
497 	if (type == NETCONFA_ALL)
498 		all = true;
499 
500 	if (all || type == NETCONFA_FORWARDING)
501 		size += nla_total_size(4);
502 #ifdef CONFIG_IPV6_MROUTE
503 	if (all || type == NETCONFA_MC_FORWARDING)
504 		size += nla_total_size(4);
505 #endif
506 	if (all || type == NETCONFA_PROXY_NEIGH)
507 		size += nla_total_size(4);
508 
509 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
510 		size += nla_total_size(4);
511 
512 	return size;
513 }
514 
515 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
516 				      struct ipv6_devconf *devconf, u32 portid,
517 				      u32 seq, int event, unsigned int flags,
518 				      int type)
519 {
520 	struct nlmsghdr  *nlh;
521 	struct netconfmsg *ncm;
522 	bool all = false;
523 
524 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
525 			flags);
526 	if (!nlh)
527 		return -EMSGSIZE;
528 
529 	if (type == NETCONFA_ALL)
530 		all = true;
531 
532 	ncm = nlmsg_data(nlh);
533 	ncm->ncm_family = AF_INET6;
534 
535 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
536 		goto nla_put_failure;
537 
538 	if (!devconf)
539 		goto out;
540 
541 	if ((all || type == NETCONFA_FORWARDING) &&
542 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
543 		goto nla_put_failure;
544 #ifdef CONFIG_IPV6_MROUTE
545 	if ((all || type == NETCONFA_MC_FORWARDING) &&
546 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
547 			devconf->mc_forwarding) < 0)
548 		goto nla_put_failure;
549 #endif
550 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
551 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
552 		goto nla_put_failure;
553 
554 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
555 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
556 			devconf->ignore_routes_with_linkdown) < 0)
557 		goto nla_put_failure;
558 
559 out:
560 	nlmsg_end(skb, nlh);
561 	return 0;
562 
563 nla_put_failure:
564 	nlmsg_cancel(skb, nlh);
565 	return -EMSGSIZE;
566 }
567 
568 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
569 				  int ifindex, struct ipv6_devconf *devconf)
570 {
571 	struct sk_buff *skb;
572 	int err = -ENOBUFS;
573 
574 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
575 	if (!skb)
576 		goto errout;
577 
578 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
579 					 event, 0, type);
580 	if (err < 0) {
581 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
582 		WARN_ON(err == -EMSGSIZE);
583 		kfree_skb(skb);
584 		goto errout;
585 	}
586 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
587 	return;
588 errout:
589 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
590 }
591 
592 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
593 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
594 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
595 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
596 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
597 };
598 
599 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
600 				       const struct nlmsghdr *nlh,
601 				       struct nlattr **tb,
602 				       struct netlink_ext_ack *extack)
603 {
604 	int i, err;
605 
606 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
607 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
608 		return -EINVAL;
609 	}
610 
611 	if (!netlink_strict_get_check(skb))
612 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
613 					      tb, NETCONFA_MAX,
614 					      devconf_ipv6_policy, extack);
615 
616 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
617 					    tb, NETCONFA_MAX,
618 					    devconf_ipv6_policy, extack);
619 	if (err)
620 		return err;
621 
622 	for (i = 0; i <= NETCONFA_MAX; i++) {
623 		if (!tb[i])
624 			continue;
625 
626 		switch (i) {
627 		case NETCONFA_IFINDEX:
628 			break;
629 		default:
630 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
631 			return -EINVAL;
632 		}
633 	}
634 
635 	return 0;
636 }
637 
638 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
639 				     struct nlmsghdr *nlh,
640 				     struct netlink_ext_ack *extack)
641 {
642 	struct net *net = sock_net(in_skb->sk);
643 	struct nlattr *tb[NETCONFA_MAX+1];
644 	struct inet6_dev *in6_dev = NULL;
645 	struct net_device *dev = NULL;
646 	struct sk_buff *skb;
647 	struct ipv6_devconf *devconf;
648 	int ifindex;
649 	int err;
650 
651 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
652 	if (err < 0)
653 		return err;
654 
655 	if (!tb[NETCONFA_IFINDEX])
656 		return -EINVAL;
657 
658 	err = -EINVAL;
659 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
660 	switch (ifindex) {
661 	case NETCONFA_IFINDEX_ALL:
662 		devconf = net->ipv6.devconf_all;
663 		break;
664 	case NETCONFA_IFINDEX_DEFAULT:
665 		devconf = net->ipv6.devconf_dflt;
666 		break;
667 	default:
668 		dev = dev_get_by_index(net, ifindex);
669 		if (!dev)
670 			return -EINVAL;
671 		in6_dev = in6_dev_get(dev);
672 		if (!in6_dev)
673 			goto errout;
674 		devconf = &in6_dev->cnf;
675 		break;
676 	}
677 
678 	err = -ENOBUFS;
679 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
680 	if (!skb)
681 		goto errout;
682 
683 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
684 					 NETLINK_CB(in_skb).portid,
685 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
686 					 NETCONFA_ALL);
687 	if (err < 0) {
688 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
689 		WARN_ON(err == -EMSGSIZE);
690 		kfree_skb(skb);
691 		goto errout;
692 	}
693 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
694 errout:
695 	if (in6_dev)
696 		in6_dev_put(in6_dev);
697 	if (dev)
698 		dev_put(dev);
699 	return err;
700 }
701 
702 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
703 				      struct netlink_callback *cb)
704 {
705 	const struct nlmsghdr *nlh = cb->nlh;
706 	struct net *net = sock_net(skb->sk);
707 	int h, s_h;
708 	int idx, s_idx;
709 	struct net_device *dev;
710 	struct inet6_dev *idev;
711 	struct hlist_head *head;
712 
713 	if (cb->strict_check) {
714 		struct netlink_ext_ack *extack = cb->extack;
715 		struct netconfmsg *ncm;
716 
717 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
718 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
719 			return -EINVAL;
720 		}
721 
722 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
723 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
724 			return -EINVAL;
725 		}
726 	}
727 
728 	s_h = cb->args[0];
729 	s_idx = idx = cb->args[1];
730 
731 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
732 		idx = 0;
733 		head = &net->dev_index_head[h];
734 		rcu_read_lock();
735 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
736 			  net->dev_base_seq;
737 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
738 			if (idx < s_idx)
739 				goto cont;
740 			idev = __in6_dev_get(dev);
741 			if (!idev)
742 				goto cont;
743 
744 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
745 						       &idev->cnf,
746 						       NETLINK_CB(cb->skb).portid,
747 						       nlh->nlmsg_seq,
748 						       RTM_NEWNETCONF,
749 						       NLM_F_MULTI,
750 						       NETCONFA_ALL) < 0) {
751 				rcu_read_unlock();
752 				goto done;
753 			}
754 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
755 cont:
756 			idx++;
757 		}
758 		rcu_read_unlock();
759 	}
760 	if (h == NETDEV_HASHENTRIES) {
761 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
762 					       net->ipv6.devconf_all,
763 					       NETLINK_CB(cb->skb).portid,
764 					       nlh->nlmsg_seq,
765 					       RTM_NEWNETCONF, NLM_F_MULTI,
766 					       NETCONFA_ALL) < 0)
767 			goto done;
768 		else
769 			h++;
770 	}
771 	if (h == NETDEV_HASHENTRIES + 1) {
772 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
773 					       net->ipv6.devconf_dflt,
774 					       NETLINK_CB(cb->skb).portid,
775 					       nlh->nlmsg_seq,
776 					       RTM_NEWNETCONF, NLM_F_MULTI,
777 					       NETCONFA_ALL) < 0)
778 			goto done;
779 		else
780 			h++;
781 	}
782 done:
783 	cb->args[0] = h;
784 	cb->args[1] = idx;
785 
786 	return skb->len;
787 }
788 
789 #ifdef CONFIG_SYSCTL
790 static void dev_forward_change(struct inet6_dev *idev)
791 {
792 	struct net_device *dev;
793 	struct inet6_ifaddr *ifa;
794 
795 	if (!idev)
796 		return;
797 	dev = idev->dev;
798 	if (idev->cnf.forwarding)
799 		dev_disable_lro(dev);
800 	if (dev->flags & IFF_MULTICAST) {
801 		if (idev->cnf.forwarding) {
802 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
803 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
804 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
805 		} else {
806 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
807 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
808 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
809 		}
810 	}
811 
812 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
813 		if (ifa->flags&IFA_F_TENTATIVE)
814 			continue;
815 		if (idev->cnf.forwarding)
816 			addrconf_join_anycast(ifa);
817 		else
818 			addrconf_leave_anycast(ifa);
819 	}
820 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
821 				     NETCONFA_FORWARDING,
822 				     dev->ifindex, &idev->cnf);
823 }
824 
825 
826 static void addrconf_forward_change(struct net *net, __s32 newf)
827 {
828 	struct net_device *dev;
829 	struct inet6_dev *idev;
830 
831 	for_each_netdev(net, dev) {
832 		idev = __in6_dev_get(dev);
833 		if (idev) {
834 			int changed = (!idev->cnf.forwarding) ^ (!newf);
835 			idev->cnf.forwarding = newf;
836 			if (changed)
837 				dev_forward_change(idev);
838 		}
839 	}
840 }
841 
842 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
843 {
844 	struct net *net;
845 	int old;
846 
847 	if (!rtnl_trylock())
848 		return restart_syscall();
849 
850 	net = (struct net *)table->extra2;
851 	old = *p;
852 	*p = newf;
853 
854 	if (p == &net->ipv6.devconf_dflt->forwarding) {
855 		if ((!newf) ^ (!old))
856 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
857 						     NETCONFA_FORWARDING,
858 						     NETCONFA_IFINDEX_DEFAULT,
859 						     net->ipv6.devconf_dflt);
860 		rtnl_unlock();
861 		return 0;
862 	}
863 
864 	if (p == &net->ipv6.devconf_all->forwarding) {
865 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
866 
867 		net->ipv6.devconf_dflt->forwarding = newf;
868 		if ((!newf) ^ (!old_dflt))
869 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
870 						     NETCONFA_FORWARDING,
871 						     NETCONFA_IFINDEX_DEFAULT,
872 						     net->ipv6.devconf_dflt);
873 
874 		addrconf_forward_change(net, newf);
875 		if ((!newf) ^ (!old))
876 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
877 						     NETCONFA_FORWARDING,
878 						     NETCONFA_IFINDEX_ALL,
879 						     net->ipv6.devconf_all);
880 	} else if ((!newf) ^ (!old))
881 		dev_forward_change((struct inet6_dev *)table->extra1);
882 	rtnl_unlock();
883 
884 	if (newf)
885 		rt6_purge_dflt_routers(net);
886 	return 1;
887 }
888 
889 static void addrconf_linkdown_change(struct net *net, __s32 newf)
890 {
891 	struct net_device *dev;
892 	struct inet6_dev *idev;
893 
894 	for_each_netdev(net, dev) {
895 		idev = __in6_dev_get(dev);
896 		if (idev) {
897 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
898 
899 			idev->cnf.ignore_routes_with_linkdown = newf;
900 			if (changed)
901 				inet6_netconf_notify_devconf(dev_net(dev),
902 							     RTM_NEWNETCONF,
903 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
904 							     dev->ifindex,
905 							     &idev->cnf);
906 		}
907 	}
908 }
909 
910 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
911 {
912 	struct net *net;
913 	int old;
914 
915 	if (!rtnl_trylock())
916 		return restart_syscall();
917 
918 	net = (struct net *)table->extra2;
919 	old = *p;
920 	*p = newf;
921 
922 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
923 		if ((!newf) ^ (!old))
924 			inet6_netconf_notify_devconf(net,
925 						     RTM_NEWNETCONF,
926 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
927 						     NETCONFA_IFINDEX_DEFAULT,
928 						     net->ipv6.devconf_dflt);
929 		rtnl_unlock();
930 		return 0;
931 	}
932 
933 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
934 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
935 		addrconf_linkdown_change(net, newf);
936 		if ((!newf) ^ (!old))
937 			inet6_netconf_notify_devconf(net,
938 						     RTM_NEWNETCONF,
939 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
940 						     NETCONFA_IFINDEX_ALL,
941 						     net->ipv6.devconf_all);
942 	}
943 	rtnl_unlock();
944 
945 	return 1;
946 }
947 
948 #endif
949 
950 /* Nobody refers to this ifaddr, destroy it */
951 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
952 {
953 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
954 
955 #ifdef NET_REFCNT_DEBUG
956 	pr_debug("%s\n", __func__);
957 #endif
958 
959 	in6_dev_put(ifp->idev);
960 
961 	if (cancel_delayed_work(&ifp->dad_work))
962 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
963 			  ifp);
964 
965 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
966 		pr_warn("Freeing alive inet6 address %p\n", ifp);
967 		return;
968 	}
969 
970 	kfree_rcu(ifp, rcu);
971 }
972 
973 static void
974 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
975 {
976 	struct list_head *p;
977 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
978 
979 	/*
980 	 * Each device address list is sorted in order of scope -
981 	 * global before linklocal.
982 	 */
983 	list_for_each(p, &idev->addr_list) {
984 		struct inet6_ifaddr *ifa
985 			= list_entry(p, struct inet6_ifaddr, if_list);
986 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
987 			break;
988 	}
989 
990 	list_add_tail_rcu(&ifp->if_list, p);
991 }
992 
993 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
994 {
995 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
996 
997 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
998 }
999 
1000 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1001 			       struct net_device *dev, unsigned int hash)
1002 {
1003 	struct inet6_ifaddr *ifp;
1004 
1005 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1006 		if (!net_eq(dev_net(ifp->idev->dev), net))
1007 			continue;
1008 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1009 			if (!dev || ifp->idev->dev == dev)
1010 				return true;
1011 		}
1012 	}
1013 	return false;
1014 }
1015 
1016 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1017 {
1018 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1019 	int err = 0;
1020 
1021 	spin_lock(&addrconf_hash_lock);
1022 
1023 	/* Ignore adding duplicate addresses on an interface */
1024 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1025 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1026 		err = -EEXIST;
1027 	} else {
1028 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1029 	}
1030 
1031 	spin_unlock(&addrconf_hash_lock);
1032 
1033 	return err;
1034 }
1035 
1036 /* On success it returns ifp with increased reference count */
1037 
1038 static struct inet6_ifaddr *
1039 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1040 	      bool can_block, struct netlink_ext_ack *extack)
1041 {
1042 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1043 	int addr_type = ipv6_addr_type(cfg->pfx);
1044 	struct net *net = dev_net(idev->dev);
1045 	struct inet6_ifaddr *ifa = NULL;
1046 	struct fib6_info *f6i = NULL;
1047 	int err = 0;
1048 
1049 	if (addr_type == IPV6_ADDR_ANY ||
1050 	    (addr_type & IPV6_ADDR_MULTICAST &&
1051 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1052 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1053 	     !netif_is_l3_master(idev->dev) &&
1054 	     addr_type & IPV6_ADDR_LOOPBACK))
1055 		return ERR_PTR(-EADDRNOTAVAIL);
1056 
1057 	if (idev->dead) {
1058 		err = -ENODEV;			/*XXX*/
1059 		goto out;
1060 	}
1061 
1062 	if (idev->cnf.disable_ipv6) {
1063 		err = -EACCES;
1064 		goto out;
1065 	}
1066 
1067 	/* validator notifier needs to be blocking;
1068 	 * do not call in atomic context
1069 	 */
1070 	if (can_block) {
1071 		struct in6_validator_info i6vi = {
1072 			.i6vi_addr = *cfg->pfx,
1073 			.i6vi_dev = idev,
1074 			.extack = extack,
1075 		};
1076 
1077 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1078 		err = notifier_to_errno(err);
1079 		if (err < 0)
1080 			goto out;
1081 	}
1082 
1083 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1084 	if (!ifa) {
1085 		err = -ENOBUFS;
1086 		goto out;
1087 	}
1088 
1089 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1090 	if (IS_ERR(f6i)) {
1091 		err = PTR_ERR(f6i);
1092 		f6i = NULL;
1093 		goto out;
1094 	}
1095 
1096 	if (net->ipv6.devconf_all->disable_policy ||
1097 	    idev->cnf.disable_policy)
1098 		f6i->dst_nopolicy = true;
1099 
1100 	neigh_parms_data_state_setall(idev->nd_parms);
1101 
1102 	ifa->addr = *cfg->pfx;
1103 	if (cfg->peer_pfx)
1104 		ifa->peer_addr = *cfg->peer_pfx;
1105 
1106 	spin_lock_init(&ifa->lock);
1107 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1108 	INIT_HLIST_NODE(&ifa->addr_lst);
1109 	ifa->scope = cfg->scope;
1110 	ifa->prefix_len = cfg->plen;
1111 	ifa->rt_priority = cfg->rt_priority;
1112 	ifa->flags = cfg->ifa_flags;
1113 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1114 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1115 		ifa->flags |= IFA_F_TENTATIVE;
1116 	ifa->valid_lft = cfg->valid_lft;
1117 	ifa->prefered_lft = cfg->preferred_lft;
1118 	ifa->cstamp = ifa->tstamp = jiffies;
1119 	ifa->tokenized = false;
1120 
1121 	ifa->rt = f6i;
1122 
1123 	ifa->idev = idev;
1124 	in6_dev_hold(idev);
1125 
1126 	/* For caller */
1127 	refcount_set(&ifa->refcnt, 1);
1128 
1129 	rcu_read_lock_bh();
1130 
1131 	err = ipv6_add_addr_hash(idev->dev, ifa);
1132 	if (err < 0) {
1133 		rcu_read_unlock_bh();
1134 		goto out;
1135 	}
1136 
1137 	write_lock(&idev->lock);
1138 
1139 	/* Add to inet6_dev unicast addr list. */
1140 	ipv6_link_dev_addr(idev, ifa);
1141 
1142 	if (ifa->flags&IFA_F_TEMPORARY) {
1143 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1144 		in6_ifa_hold(ifa);
1145 	}
1146 
1147 	in6_ifa_hold(ifa);
1148 	write_unlock(&idev->lock);
1149 
1150 	rcu_read_unlock_bh();
1151 
1152 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1153 out:
1154 	if (unlikely(err < 0)) {
1155 		fib6_info_release(f6i);
1156 
1157 		if (ifa) {
1158 			if (ifa->idev)
1159 				in6_dev_put(ifa->idev);
1160 			kfree(ifa);
1161 		}
1162 		ifa = ERR_PTR(err);
1163 	}
1164 
1165 	return ifa;
1166 }
1167 
1168 enum cleanup_prefix_rt_t {
1169 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1170 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1171 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1172 };
1173 
1174 /*
1175  * Check, whether the prefix for ifp would still need a prefix route
1176  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1177  * constants.
1178  *
1179  * 1) we don't purge prefix if address was not permanent.
1180  *    prefix is managed by its own lifetime.
1181  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1182  * 3) if there are no addresses, delete prefix.
1183  * 4) if there are still other permanent address(es),
1184  *    corresponding prefix is still permanent.
1185  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1186  *    don't purge the prefix, assume user space is managing it.
1187  * 6) otherwise, update prefix lifetime to the
1188  *    longest valid lifetime among the corresponding
1189  *    addresses on the device.
1190  *    Note: subsequent RA will update lifetime.
1191  **/
1192 static enum cleanup_prefix_rt_t
1193 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1194 {
1195 	struct inet6_ifaddr *ifa;
1196 	struct inet6_dev *idev = ifp->idev;
1197 	unsigned long lifetime;
1198 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1199 
1200 	*expires = jiffies;
1201 
1202 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1203 		if (ifa == ifp)
1204 			continue;
1205 		if (ifa->prefix_len != ifp->prefix_len ||
1206 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1207 				       ifp->prefix_len))
1208 			continue;
1209 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1210 			return CLEANUP_PREFIX_RT_NOP;
1211 
1212 		action = CLEANUP_PREFIX_RT_EXPIRE;
1213 
1214 		spin_lock(&ifa->lock);
1215 
1216 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1217 		/*
1218 		 * Note: Because this address is
1219 		 * not permanent, lifetime <
1220 		 * LONG_MAX / HZ here.
1221 		 */
1222 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1223 			*expires = ifa->tstamp + lifetime * HZ;
1224 		spin_unlock(&ifa->lock);
1225 	}
1226 
1227 	return action;
1228 }
1229 
1230 static void
1231 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1232 		     bool del_rt, bool del_peer)
1233 {
1234 	struct fib6_info *f6i;
1235 
1236 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1237 					ifp->prefix_len,
1238 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1239 	if (f6i) {
1240 		if (del_rt)
1241 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1242 		else {
1243 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1244 				fib6_set_expires(f6i, expires);
1245 			fib6_info_release(f6i);
1246 		}
1247 	}
1248 }
1249 
1250 
1251 /* This function wants to get referenced ifp and releases it before return */
1252 
1253 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1254 {
1255 	int state;
1256 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1257 	unsigned long expires;
1258 
1259 	ASSERT_RTNL();
1260 
1261 	spin_lock_bh(&ifp->lock);
1262 	state = ifp->state;
1263 	ifp->state = INET6_IFADDR_STATE_DEAD;
1264 	spin_unlock_bh(&ifp->lock);
1265 
1266 	if (state == INET6_IFADDR_STATE_DEAD)
1267 		goto out;
1268 
1269 	spin_lock_bh(&addrconf_hash_lock);
1270 	hlist_del_init_rcu(&ifp->addr_lst);
1271 	spin_unlock_bh(&addrconf_hash_lock);
1272 
1273 	write_lock_bh(&ifp->idev->lock);
1274 
1275 	if (ifp->flags&IFA_F_TEMPORARY) {
1276 		list_del(&ifp->tmp_list);
1277 		if (ifp->ifpub) {
1278 			in6_ifa_put(ifp->ifpub);
1279 			ifp->ifpub = NULL;
1280 		}
1281 		__in6_ifa_put(ifp);
1282 	}
1283 
1284 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1285 		action = check_cleanup_prefix_route(ifp, &expires);
1286 
1287 	list_del_rcu(&ifp->if_list);
1288 	__in6_ifa_put(ifp);
1289 
1290 	write_unlock_bh(&ifp->idev->lock);
1291 
1292 	addrconf_del_dad_work(ifp);
1293 
1294 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1295 
1296 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1297 
1298 	if (action != CLEANUP_PREFIX_RT_NOP) {
1299 		cleanup_prefix_route(ifp, expires,
1300 			action == CLEANUP_PREFIX_RT_DEL, false);
1301 	}
1302 
1303 	/* clean up prefsrc entries */
1304 	rt6_remove_prefsrc(ifp);
1305 out:
1306 	in6_ifa_put(ifp);
1307 }
1308 
1309 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1310 				struct inet6_ifaddr *ift,
1311 				bool block)
1312 {
1313 	struct inet6_dev *idev = ifp->idev;
1314 	struct in6_addr addr, *tmpaddr;
1315 	unsigned long tmp_tstamp, age;
1316 	unsigned long regen_advance;
1317 	struct ifa6_config cfg;
1318 	int ret = 0;
1319 	unsigned long now = jiffies;
1320 	long max_desync_factor;
1321 	s32 cnf_temp_preferred_lft;
1322 
1323 	write_lock_bh(&idev->lock);
1324 	if (ift) {
1325 		spin_lock_bh(&ift->lock);
1326 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1327 		spin_unlock_bh(&ift->lock);
1328 		tmpaddr = &addr;
1329 	} else {
1330 		tmpaddr = NULL;
1331 	}
1332 retry:
1333 	in6_dev_hold(idev);
1334 	if (idev->cnf.use_tempaddr <= 0) {
1335 		write_unlock_bh(&idev->lock);
1336 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1337 		in6_dev_put(idev);
1338 		ret = -1;
1339 		goto out;
1340 	}
1341 	spin_lock_bh(&ifp->lock);
1342 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1343 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1344 		spin_unlock_bh(&ifp->lock);
1345 		write_unlock_bh(&idev->lock);
1346 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1347 			__func__);
1348 		in6_dev_put(idev);
1349 		ret = -1;
1350 		goto out;
1351 	}
1352 	in6_ifa_hold(ifp);
1353 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1354 	ipv6_try_regen_rndid(idev, tmpaddr);
1355 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1356 	age = (now - ifp->tstamp) / HZ;
1357 
1358 	regen_advance = idev->cnf.regen_max_retry *
1359 			idev->cnf.dad_transmits *
1360 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1361 
1362 	/* recalculate max_desync_factor each time and update
1363 	 * idev->desync_factor if it's larger
1364 	 */
1365 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1366 	max_desync_factor = min_t(__u32,
1367 				  idev->cnf.max_desync_factor,
1368 				  cnf_temp_preferred_lft - regen_advance);
1369 
1370 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1371 		if (max_desync_factor > 0) {
1372 			get_random_bytes(&idev->desync_factor,
1373 					 sizeof(idev->desync_factor));
1374 			idev->desync_factor %= max_desync_factor;
1375 		} else {
1376 			idev->desync_factor = 0;
1377 		}
1378 	}
1379 
1380 	memset(&cfg, 0, sizeof(cfg));
1381 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1382 			      idev->cnf.temp_valid_lft + age);
1383 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1384 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1385 
1386 	cfg.plen = ifp->prefix_len;
1387 	tmp_tstamp = ifp->tstamp;
1388 	spin_unlock_bh(&ifp->lock);
1389 
1390 	write_unlock_bh(&idev->lock);
1391 
1392 	/* A temporary address is created only if this calculated Preferred
1393 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1394 	 * an implementation must not create a temporary address with a zero
1395 	 * Preferred Lifetime.
1396 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1397 	 * temporary addresses being generated.
1398 	 */
1399 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1400 	if (cfg.preferred_lft <= regen_advance + age) {
1401 		in6_ifa_put(ifp);
1402 		in6_dev_put(idev);
1403 		ret = -1;
1404 		goto out;
1405 	}
1406 
1407 	cfg.ifa_flags = IFA_F_TEMPORARY;
1408 	/* set in addrconf_prefix_rcv() */
1409 	if (ifp->flags & IFA_F_OPTIMISTIC)
1410 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1411 
1412 	cfg.pfx = &addr;
1413 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1414 
1415 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1416 	if (IS_ERR(ift)) {
1417 		in6_ifa_put(ifp);
1418 		in6_dev_put(idev);
1419 		pr_info("%s: retry temporary address regeneration\n", __func__);
1420 		tmpaddr = &addr;
1421 		write_lock_bh(&idev->lock);
1422 		goto retry;
1423 	}
1424 
1425 	spin_lock_bh(&ift->lock);
1426 	ift->ifpub = ifp;
1427 	ift->cstamp = now;
1428 	ift->tstamp = tmp_tstamp;
1429 	spin_unlock_bh(&ift->lock);
1430 
1431 	addrconf_dad_start(ift);
1432 	in6_ifa_put(ift);
1433 	in6_dev_put(idev);
1434 out:
1435 	return ret;
1436 }
1437 
1438 /*
1439  *	Choose an appropriate source address (RFC3484)
1440  */
1441 enum {
1442 	IPV6_SADDR_RULE_INIT = 0,
1443 	IPV6_SADDR_RULE_LOCAL,
1444 	IPV6_SADDR_RULE_SCOPE,
1445 	IPV6_SADDR_RULE_PREFERRED,
1446 #ifdef CONFIG_IPV6_MIP6
1447 	IPV6_SADDR_RULE_HOA,
1448 #endif
1449 	IPV6_SADDR_RULE_OIF,
1450 	IPV6_SADDR_RULE_LABEL,
1451 	IPV6_SADDR_RULE_PRIVACY,
1452 	IPV6_SADDR_RULE_ORCHID,
1453 	IPV6_SADDR_RULE_PREFIX,
1454 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1455 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1456 #endif
1457 	IPV6_SADDR_RULE_MAX
1458 };
1459 
1460 struct ipv6_saddr_score {
1461 	int			rule;
1462 	int			addr_type;
1463 	struct inet6_ifaddr	*ifa;
1464 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1465 	int			scopedist;
1466 	int			matchlen;
1467 };
1468 
1469 struct ipv6_saddr_dst {
1470 	const struct in6_addr *addr;
1471 	int ifindex;
1472 	int scope;
1473 	int label;
1474 	unsigned int prefs;
1475 };
1476 
1477 static inline int ipv6_saddr_preferred(int type)
1478 {
1479 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1480 		return 1;
1481 	return 0;
1482 }
1483 
1484 static bool ipv6_use_optimistic_addr(struct net *net,
1485 				     struct inet6_dev *idev)
1486 {
1487 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1488 	if (!idev)
1489 		return false;
1490 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1491 		return false;
1492 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1493 		return false;
1494 
1495 	return true;
1496 #else
1497 	return false;
1498 #endif
1499 }
1500 
1501 static bool ipv6_allow_optimistic_dad(struct net *net,
1502 				      struct inet6_dev *idev)
1503 {
1504 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1505 	if (!idev)
1506 		return false;
1507 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1508 		return false;
1509 
1510 	return true;
1511 #else
1512 	return false;
1513 #endif
1514 }
1515 
1516 static int ipv6_get_saddr_eval(struct net *net,
1517 			       struct ipv6_saddr_score *score,
1518 			       struct ipv6_saddr_dst *dst,
1519 			       int i)
1520 {
1521 	int ret;
1522 
1523 	if (i <= score->rule) {
1524 		switch (i) {
1525 		case IPV6_SADDR_RULE_SCOPE:
1526 			ret = score->scopedist;
1527 			break;
1528 		case IPV6_SADDR_RULE_PREFIX:
1529 			ret = score->matchlen;
1530 			break;
1531 		default:
1532 			ret = !!test_bit(i, score->scorebits);
1533 		}
1534 		goto out;
1535 	}
1536 
1537 	switch (i) {
1538 	case IPV6_SADDR_RULE_INIT:
1539 		/* Rule 0: remember if hiscore is not ready yet */
1540 		ret = !!score->ifa;
1541 		break;
1542 	case IPV6_SADDR_RULE_LOCAL:
1543 		/* Rule 1: Prefer same address */
1544 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1545 		break;
1546 	case IPV6_SADDR_RULE_SCOPE:
1547 		/* Rule 2: Prefer appropriate scope
1548 		 *
1549 		 *      ret
1550 		 *       ^
1551 		 *    -1 |  d 15
1552 		 *    ---+--+-+---> scope
1553 		 *       |
1554 		 *       |             d is scope of the destination.
1555 		 *  B-d  |  \
1556 		 *       |   \      <- smaller scope is better if
1557 		 *  B-15 |    \        if scope is enough for destination.
1558 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1559 		 * d-C-1 | /
1560 		 *       |/         <- greater is better
1561 		 *   -C  /             if scope is not enough for destination.
1562 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1563 		 *
1564 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1565 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1566 		 * Assume B = 0 and we get C > 29.
1567 		 */
1568 		ret = __ipv6_addr_src_scope(score->addr_type);
1569 		if (ret >= dst->scope)
1570 			ret = -ret;
1571 		else
1572 			ret -= 128;	/* 30 is enough */
1573 		score->scopedist = ret;
1574 		break;
1575 	case IPV6_SADDR_RULE_PREFERRED:
1576 	    {
1577 		/* Rule 3: Avoid deprecated and optimistic addresses */
1578 		u8 avoid = IFA_F_DEPRECATED;
1579 
1580 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1581 			avoid |= IFA_F_OPTIMISTIC;
1582 		ret = ipv6_saddr_preferred(score->addr_type) ||
1583 		      !(score->ifa->flags & avoid);
1584 		break;
1585 	    }
1586 #ifdef CONFIG_IPV6_MIP6
1587 	case IPV6_SADDR_RULE_HOA:
1588 	    {
1589 		/* Rule 4: Prefer home address */
1590 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1591 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1592 		break;
1593 	    }
1594 #endif
1595 	case IPV6_SADDR_RULE_OIF:
1596 		/* Rule 5: Prefer outgoing interface */
1597 		ret = (!dst->ifindex ||
1598 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1599 		break;
1600 	case IPV6_SADDR_RULE_LABEL:
1601 		/* Rule 6: Prefer matching label */
1602 		ret = ipv6_addr_label(net,
1603 				      &score->ifa->addr, score->addr_type,
1604 				      score->ifa->idev->dev->ifindex) == dst->label;
1605 		break;
1606 	case IPV6_SADDR_RULE_PRIVACY:
1607 	    {
1608 		/* Rule 7: Prefer public address
1609 		 * Note: prefer temporary address if use_tempaddr >= 2
1610 		 */
1611 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1612 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1613 				score->ifa->idev->cnf.use_tempaddr >= 2;
1614 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1615 		break;
1616 	    }
1617 	case IPV6_SADDR_RULE_ORCHID:
1618 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1619 		 *	    non-ORCHID vs non-ORCHID
1620 		 */
1621 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1622 			ipv6_addr_orchid(dst->addr));
1623 		break;
1624 	case IPV6_SADDR_RULE_PREFIX:
1625 		/* Rule 8: Use longest matching prefix */
1626 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1627 		if (ret > score->ifa->prefix_len)
1628 			ret = score->ifa->prefix_len;
1629 		score->matchlen = ret;
1630 		break;
1631 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1632 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1633 		/* Optimistic addresses still have lower precedence than other
1634 		 * preferred addresses.
1635 		 */
1636 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1637 		break;
1638 #endif
1639 	default:
1640 		ret = 0;
1641 	}
1642 
1643 	if (ret)
1644 		__set_bit(i, score->scorebits);
1645 	score->rule = i;
1646 out:
1647 	return ret;
1648 }
1649 
1650 static int __ipv6_dev_get_saddr(struct net *net,
1651 				struct ipv6_saddr_dst *dst,
1652 				struct inet6_dev *idev,
1653 				struct ipv6_saddr_score *scores,
1654 				int hiscore_idx)
1655 {
1656 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1657 
1658 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1659 		int i;
1660 
1661 		/*
1662 		 * - Tentative Address (RFC2462 section 5.4)
1663 		 *  - A tentative address is not considered
1664 		 *    "assigned to an interface" in the traditional
1665 		 *    sense, unless it is also flagged as optimistic.
1666 		 * - Candidate Source Address (section 4)
1667 		 *  - In any case, anycast addresses, multicast
1668 		 *    addresses, and the unspecified address MUST
1669 		 *    NOT be included in a candidate set.
1670 		 */
1671 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1672 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1673 			continue;
1674 
1675 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1676 
1677 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1678 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1679 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1680 					    idev->dev->name);
1681 			continue;
1682 		}
1683 
1684 		score->rule = -1;
1685 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1686 
1687 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1688 			int minihiscore, miniscore;
1689 
1690 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1691 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1692 
1693 			if (minihiscore > miniscore) {
1694 				if (i == IPV6_SADDR_RULE_SCOPE &&
1695 				    score->scopedist > 0) {
1696 					/*
1697 					 * special case:
1698 					 * each remaining entry
1699 					 * has too small (not enough)
1700 					 * scope, because ifa entries
1701 					 * are sorted by their scope
1702 					 * values.
1703 					 */
1704 					goto out;
1705 				}
1706 				break;
1707 			} else if (minihiscore < miniscore) {
1708 				swap(hiscore, score);
1709 				hiscore_idx = 1 - hiscore_idx;
1710 
1711 				/* restore our iterator */
1712 				score->ifa = hiscore->ifa;
1713 
1714 				break;
1715 			}
1716 		}
1717 	}
1718 out:
1719 	return hiscore_idx;
1720 }
1721 
1722 static int ipv6_get_saddr_master(struct net *net,
1723 				 const struct net_device *dst_dev,
1724 				 const struct net_device *master,
1725 				 struct ipv6_saddr_dst *dst,
1726 				 struct ipv6_saddr_score *scores,
1727 				 int hiscore_idx)
1728 {
1729 	struct inet6_dev *idev;
1730 
1731 	idev = __in6_dev_get(dst_dev);
1732 	if (idev)
1733 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1734 						   scores, hiscore_idx);
1735 
1736 	idev = __in6_dev_get(master);
1737 	if (idev)
1738 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1739 						   scores, hiscore_idx);
1740 
1741 	return hiscore_idx;
1742 }
1743 
1744 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1745 		       const struct in6_addr *daddr, unsigned int prefs,
1746 		       struct in6_addr *saddr)
1747 {
1748 	struct ipv6_saddr_score scores[2], *hiscore;
1749 	struct ipv6_saddr_dst dst;
1750 	struct inet6_dev *idev;
1751 	struct net_device *dev;
1752 	int dst_type;
1753 	bool use_oif_addr = false;
1754 	int hiscore_idx = 0;
1755 	int ret = 0;
1756 
1757 	dst_type = __ipv6_addr_type(daddr);
1758 	dst.addr = daddr;
1759 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1760 	dst.scope = __ipv6_addr_src_scope(dst_type);
1761 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1762 	dst.prefs = prefs;
1763 
1764 	scores[hiscore_idx].rule = -1;
1765 	scores[hiscore_idx].ifa = NULL;
1766 
1767 	rcu_read_lock();
1768 
1769 	/* Candidate Source Address (section 4)
1770 	 *  - multicast and link-local destination address,
1771 	 *    the set of candidate source address MUST only
1772 	 *    include addresses assigned to interfaces
1773 	 *    belonging to the same link as the outgoing
1774 	 *    interface.
1775 	 * (- For site-local destination addresses, the
1776 	 *    set of candidate source addresses MUST only
1777 	 *    include addresses assigned to interfaces
1778 	 *    belonging to the same site as the outgoing
1779 	 *    interface.)
1780 	 *  - "It is RECOMMENDED that the candidate source addresses
1781 	 *    be the set of unicast addresses assigned to the
1782 	 *    interface that will be used to send to the destination
1783 	 *    (the 'outgoing' interface)." (RFC 6724)
1784 	 */
1785 	if (dst_dev) {
1786 		idev = __in6_dev_get(dst_dev);
1787 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1788 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1789 		    (idev && idev->cnf.use_oif_addrs_only)) {
1790 			use_oif_addr = true;
1791 		}
1792 	}
1793 
1794 	if (use_oif_addr) {
1795 		if (idev)
1796 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1797 	} else {
1798 		const struct net_device *master;
1799 		int master_idx = 0;
1800 
1801 		/* if dst_dev exists and is enslaved to an L3 device, then
1802 		 * prefer addresses from dst_dev and then the master over
1803 		 * any other enslaved devices in the L3 domain.
1804 		 */
1805 		master = l3mdev_master_dev_rcu(dst_dev);
1806 		if (master) {
1807 			master_idx = master->ifindex;
1808 
1809 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1810 							    master, &dst,
1811 							    scores, hiscore_idx);
1812 
1813 			if (scores[hiscore_idx].ifa)
1814 				goto out;
1815 		}
1816 
1817 		for_each_netdev_rcu(net, dev) {
1818 			/* only consider addresses on devices in the
1819 			 * same L3 domain
1820 			 */
1821 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1822 				continue;
1823 			idev = __in6_dev_get(dev);
1824 			if (!idev)
1825 				continue;
1826 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1827 		}
1828 	}
1829 
1830 out:
1831 	hiscore = &scores[hiscore_idx];
1832 	if (!hiscore->ifa)
1833 		ret = -EADDRNOTAVAIL;
1834 	else
1835 		*saddr = hiscore->ifa->addr;
1836 
1837 	rcu_read_unlock();
1838 	return ret;
1839 }
1840 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1841 
1842 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1843 		      u32 banned_flags)
1844 {
1845 	struct inet6_ifaddr *ifp;
1846 	int err = -EADDRNOTAVAIL;
1847 
1848 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1849 		if (ifp->scope > IFA_LINK)
1850 			break;
1851 		if (ifp->scope == IFA_LINK &&
1852 		    !(ifp->flags & banned_flags)) {
1853 			*addr = ifp->addr;
1854 			err = 0;
1855 			break;
1856 		}
1857 	}
1858 	return err;
1859 }
1860 
1861 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1862 		    u32 banned_flags)
1863 {
1864 	struct inet6_dev *idev;
1865 	int err = -EADDRNOTAVAIL;
1866 
1867 	rcu_read_lock();
1868 	idev = __in6_dev_get(dev);
1869 	if (idev) {
1870 		read_lock_bh(&idev->lock);
1871 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1872 		read_unlock_bh(&idev->lock);
1873 	}
1874 	rcu_read_unlock();
1875 	return err;
1876 }
1877 
1878 static int ipv6_count_addresses(const struct inet6_dev *idev)
1879 {
1880 	const struct inet6_ifaddr *ifp;
1881 	int cnt = 0;
1882 
1883 	rcu_read_lock();
1884 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1885 		cnt++;
1886 	rcu_read_unlock();
1887 	return cnt;
1888 }
1889 
1890 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1891 		  const struct net_device *dev, int strict)
1892 {
1893 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1894 				       strict, IFA_F_TENTATIVE);
1895 }
1896 EXPORT_SYMBOL(ipv6_chk_addr);
1897 
1898 /* device argument is used to find the L3 domain of interest. If
1899  * skip_dev_check is set, then the ifp device is not checked against
1900  * the passed in dev argument. So the 2 cases for addresses checks are:
1901  *   1. does the address exist in the L3 domain that dev is part of
1902  *      (skip_dev_check = true), or
1903  *
1904  *   2. does the address exist on the specific device
1905  *      (skip_dev_check = false)
1906  */
1907 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1908 			    const struct net_device *dev, bool skip_dev_check,
1909 			    int strict, u32 banned_flags)
1910 {
1911 	unsigned int hash = inet6_addr_hash(net, addr);
1912 	const struct net_device *l3mdev;
1913 	struct inet6_ifaddr *ifp;
1914 	u32 ifp_flags;
1915 
1916 	rcu_read_lock();
1917 
1918 	l3mdev = l3mdev_master_dev_rcu(dev);
1919 	if (skip_dev_check)
1920 		dev = NULL;
1921 
1922 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1923 		if (!net_eq(dev_net(ifp->idev->dev), net))
1924 			continue;
1925 
1926 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1927 			continue;
1928 
1929 		/* Decouple optimistic from tentative for evaluation here.
1930 		 * Ban optimistic addresses explicitly, when required.
1931 		 */
1932 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1933 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1934 			    : ifp->flags;
1935 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1936 		    !(ifp_flags&banned_flags) &&
1937 		    (!dev || ifp->idev->dev == dev ||
1938 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1939 			rcu_read_unlock();
1940 			return 1;
1941 		}
1942 	}
1943 
1944 	rcu_read_unlock();
1945 	return 0;
1946 }
1947 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1948 
1949 
1950 /* Compares an address/prefix_len with addresses on device @dev.
1951  * If one is found it returns true.
1952  */
1953 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1954 	const unsigned int prefix_len, struct net_device *dev)
1955 {
1956 	const struct inet6_ifaddr *ifa;
1957 	const struct inet6_dev *idev;
1958 	bool ret = false;
1959 
1960 	rcu_read_lock();
1961 	idev = __in6_dev_get(dev);
1962 	if (idev) {
1963 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1964 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1965 			if (ret)
1966 				break;
1967 		}
1968 	}
1969 	rcu_read_unlock();
1970 
1971 	return ret;
1972 }
1973 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1974 
1975 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1976 {
1977 	const struct inet6_ifaddr *ifa;
1978 	const struct inet6_dev *idev;
1979 	int	onlink;
1980 
1981 	onlink = 0;
1982 	rcu_read_lock();
1983 	idev = __in6_dev_get(dev);
1984 	if (idev) {
1985 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1986 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1987 						   ifa->prefix_len);
1988 			if (onlink)
1989 				break;
1990 		}
1991 	}
1992 	rcu_read_unlock();
1993 	return onlink;
1994 }
1995 EXPORT_SYMBOL(ipv6_chk_prefix);
1996 
1997 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1998 				     struct net_device *dev, int strict)
1999 {
2000 	unsigned int hash = inet6_addr_hash(net, addr);
2001 	struct inet6_ifaddr *ifp, *result = NULL;
2002 
2003 	rcu_read_lock();
2004 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2005 		if (!net_eq(dev_net(ifp->idev->dev), net))
2006 			continue;
2007 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2008 			if (!dev || ifp->idev->dev == dev ||
2009 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2010 				result = ifp;
2011 				in6_ifa_hold(ifp);
2012 				break;
2013 			}
2014 		}
2015 	}
2016 	rcu_read_unlock();
2017 
2018 	return result;
2019 }
2020 
2021 /* Gets referenced address, destroys ifaddr */
2022 
2023 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2024 {
2025 	if (dad_failed)
2026 		ifp->flags |= IFA_F_DADFAILED;
2027 
2028 	if (ifp->flags&IFA_F_TEMPORARY) {
2029 		struct inet6_ifaddr *ifpub;
2030 		spin_lock_bh(&ifp->lock);
2031 		ifpub = ifp->ifpub;
2032 		if (ifpub) {
2033 			in6_ifa_hold(ifpub);
2034 			spin_unlock_bh(&ifp->lock);
2035 			ipv6_create_tempaddr(ifpub, ifp, true);
2036 			in6_ifa_put(ifpub);
2037 		} else {
2038 			spin_unlock_bh(&ifp->lock);
2039 		}
2040 		ipv6_del_addr(ifp);
2041 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2042 		spin_lock_bh(&ifp->lock);
2043 		addrconf_del_dad_work(ifp);
2044 		ifp->flags |= IFA_F_TENTATIVE;
2045 		if (dad_failed)
2046 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2047 		spin_unlock_bh(&ifp->lock);
2048 		if (dad_failed)
2049 			ipv6_ifa_notify(0, ifp);
2050 		in6_ifa_put(ifp);
2051 	} else {
2052 		ipv6_del_addr(ifp);
2053 	}
2054 }
2055 
2056 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2057 {
2058 	int err = -ENOENT;
2059 
2060 	spin_lock_bh(&ifp->lock);
2061 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2062 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2063 		err = 0;
2064 	}
2065 	spin_unlock_bh(&ifp->lock);
2066 
2067 	return err;
2068 }
2069 
2070 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2071 {
2072 	struct inet6_dev *idev = ifp->idev;
2073 	struct net *net = dev_net(ifp->idev->dev);
2074 
2075 	if (addrconf_dad_end(ifp)) {
2076 		in6_ifa_put(ifp);
2077 		return;
2078 	}
2079 
2080 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2081 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2082 
2083 	spin_lock_bh(&ifp->lock);
2084 
2085 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2086 		struct in6_addr new_addr;
2087 		struct inet6_ifaddr *ifp2;
2088 		int retries = ifp->stable_privacy_retry + 1;
2089 		struct ifa6_config cfg = {
2090 			.pfx = &new_addr,
2091 			.plen = ifp->prefix_len,
2092 			.ifa_flags = ifp->flags,
2093 			.valid_lft = ifp->valid_lft,
2094 			.preferred_lft = ifp->prefered_lft,
2095 			.scope = ifp->scope,
2096 		};
2097 
2098 		if (retries > net->ipv6.sysctl.idgen_retries) {
2099 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2100 					     ifp->idev->dev->name);
2101 			goto errdad;
2102 		}
2103 
2104 		new_addr = ifp->addr;
2105 		if (ipv6_generate_stable_address(&new_addr, retries,
2106 						 idev))
2107 			goto errdad;
2108 
2109 		spin_unlock_bh(&ifp->lock);
2110 
2111 		if (idev->cnf.max_addresses &&
2112 		    ipv6_count_addresses(idev) >=
2113 		    idev->cnf.max_addresses)
2114 			goto lock_errdad;
2115 
2116 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2117 				     ifp->idev->dev->name);
2118 
2119 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2120 		if (IS_ERR(ifp2))
2121 			goto lock_errdad;
2122 
2123 		spin_lock_bh(&ifp2->lock);
2124 		ifp2->stable_privacy_retry = retries;
2125 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2126 		spin_unlock_bh(&ifp2->lock);
2127 
2128 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2129 		in6_ifa_put(ifp2);
2130 lock_errdad:
2131 		spin_lock_bh(&ifp->lock);
2132 	}
2133 
2134 errdad:
2135 	/* transition from _POSTDAD to _ERRDAD */
2136 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2137 	spin_unlock_bh(&ifp->lock);
2138 
2139 	addrconf_mod_dad_work(ifp, 0);
2140 	in6_ifa_put(ifp);
2141 }
2142 
2143 /* Join to solicited addr multicast group.
2144  * caller must hold RTNL */
2145 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2146 {
2147 	struct in6_addr maddr;
2148 
2149 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2150 		return;
2151 
2152 	addrconf_addr_solict_mult(addr, &maddr);
2153 	ipv6_dev_mc_inc(dev, &maddr);
2154 }
2155 
2156 /* caller must hold RTNL */
2157 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2158 {
2159 	struct in6_addr maddr;
2160 
2161 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2162 		return;
2163 
2164 	addrconf_addr_solict_mult(addr, &maddr);
2165 	__ipv6_dev_mc_dec(idev, &maddr);
2166 }
2167 
2168 /* caller must hold RTNL */
2169 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2170 {
2171 	struct in6_addr addr;
2172 
2173 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2174 		return;
2175 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2176 	if (ipv6_addr_any(&addr))
2177 		return;
2178 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2179 }
2180 
2181 /* caller must hold RTNL */
2182 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2183 {
2184 	struct in6_addr addr;
2185 
2186 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2187 		return;
2188 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2189 	if (ipv6_addr_any(&addr))
2190 		return;
2191 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2192 }
2193 
2194 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2195 {
2196 	switch (dev->addr_len) {
2197 	case ETH_ALEN:
2198 		memcpy(eui, dev->dev_addr, 3);
2199 		eui[3] = 0xFF;
2200 		eui[4] = 0xFE;
2201 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2202 		break;
2203 	case EUI64_ADDR_LEN:
2204 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2205 		eui[0] ^= 2;
2206 		break;
2207 	default:
2208 		return -1;
2209 	}
2210 
2211 	return 0;
2212 }
2213 
2214 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2215 {
2216 	union fwnet_hwaddr *ha;
2217 
2218 	if (dev->addr_len != FWNET_ALEN)
2219 		return -1;
2220 
2221 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2222 
2223 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2224 	eui[0] ^= 2;
2225 	return 0;
2226 }
2227 
2228 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2229 {
2230 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2231 	if (dev->addr_len != ARCNET_ALEN)
2232 		return -1;
2233 	memset(eui, 0, 7);
2234 	eui[7] = *(u8 *)dev->dev_addr;
2235 	return 0;
2236 }
2237 
2238 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2239 {
2240 	if (dev->addr_len != INFINIBAND_ALEN)
2241 		return -1;
2242 	memcpy(eui, dev->dev_addr + 12, 8);
2243 	eui[0] |= 2;
2244 	return 0;
2245 }
2246 
2247 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2248 {
2249 	if (addr == 0)
2250 		return -1;
2251 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2252 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2253 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2254 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2255 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2256 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2257 	eui[1] = 0;
2258 	eui[2] = 0x5E;
2259 	eui[3] = 0xFE;
2260 	memcpy(eui + 4, &addr, 4);
2261 	return 0;
2262 }
2263 
2264 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2265 {
2266 	if (dev->priv_flags & IFF_ISATAP)
2267 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2268 	return -1;
2269 }
2270 
2271 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2272 {
2273 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2274 }
2275 
2276 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2277 {
2278 	memcpy(eui, dev->perm_addr, 3);
2279 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2280 	eui[3] = 0xFF;
2281 	eui[4] = 0xFE;
2282 	eui[0] ^= 2;
2283 	return 0;
2284 }
2285 
2286 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2287 {
2288 	switch (dev->type) {
2289 	case ARPHRD_ETHER:
2290 	case ARPHRD_FDDI:
2291 		return addrconf_ifid_eui48(eui, dev);
2292 	case ARPHRD_ARCNET:
2293 		return addrconf_ifid_arcnet(eui, dev);
2294 	case ARPHRD_INFINIBAND:
2295 		return addrconf_ifid_infiniband(eui, dev);
2296 	case ARPHRD_SIT:
2297 		return addrconf_ifid_sit(eui, dev);
2298 	case ARPHRD_IPGRE:
2299 	case ARPHRD_TUNNEL:
2300 		return addrconf_ifid_gre(eui, dev);
2301 	case ARPHRD_6LOWPAN:
2302 		return addrconf_ifid_6lowpan(eui, dev);
2303 	case ARPHRD_IEEE1394:
2304 		return addrconf_ifid_ieee1394(eui, dev);
2305 	case ARPHRD_TUNNEL6:
2306 	case ARPHRD_IP6GRE:
2307 	case ARPHRD_RAWIP:
2308 		return addrconf_ifid_ip6tnl(eui, dev);
2309 	}
2310 	return -1;
2311 }
2312 
2313 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2314 {
2315 	int err = -1;
2316 	struct inet6_ifaddr *ifp;
2317 
2318 	read_lock_bh(&idev->lock);
2319 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2320 		if (ifp->scope > IFA_LINK)
2321 			break;
2322 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2323 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2324 			err = 0;
2325 			break;
2326 		}
2327 	}
2328 	read_unlock_bh(&idev->lock);
2329 	return err;
2330 }
2331 
2332 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2333 static void ipv6_regen_rndid(struct inet6_dev *idev)
2334 {
2335 regen:
2336 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2337 	idev->rndid[0] &= ~0x02;
2338 
2339 	/*
2340 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2341 	 * check if generated address is not inappropriate
2342 	 *
2343 	 *  - Reserved subnet anycast (RFC 2526)
2344 	 *	11111101 11....11 1xxxxxxx
2345 	 *  - ISATAP (RFC4214) 6.1
2346 	 *	00-00-5E-FE-xx-xx-xx-xx
2347 	 *  - value 0
2348 	 *  - XXX: already assigned to an address on the device
2349 	 */
2350 	if (idev->rndid[0] == 0xfd &&
2351 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2352 	    (idev->rndid[7]&0x80))
2353 		goto regen;
2354 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2355 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2356 			goto regen;
2357 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2358 			goto regen;
2359 	}
2360 }
2361 
2362 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2363 {
2364 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2365 		ipv6_regen_rndid(idev);
2366 }
2367 
2368 /*
2369  *	Add prefix route.
2370  */
2371 
2372 static void
2373 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2374 		      struct net_device *dev, unsigned long expires,
2375 		      u32 flags, gfp_t gfp_flags)
2376 {
2377 	struct fib6_config cfg = {
2378 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2379 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2380 		.fc_ifindex = dev->ifindex,
2381 		.fc_expires = expires,
2382 		.fc_dst_len = plen,
2383 		.fc_flags = RTF_UP | flags,
2384 		.fc_nlinfo.nl_net = dev_net(dev),
2385 		.fc_protocol = RTPROT_KERNEL,
2386 		.fc_type = RTN_UNICAST,
2387 	};
2388 
2389 	cfg.fc_dst = *pfx;
2390 
2391 	/* Prevent useless cloning on PtP SIT.
2392 	   This thing is done here expecting that the whole
2393 	   class of non-broadcast devices need not cloning.
2394 	 */
2395 #if IS_ENABLED(CONFIG_IPV6_SIT)
2396 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2397 		cfg.fc_flags |= RTF_NONEXTHOP;
2398 #endif
2399 
2400 	ip6_route_add(&cfg, gfp_flags, NULL);
2401 }
2402 
2403 
2404 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2405 						  int plen,
2406 						  const struct net_device *dev,
2407 						  u32 flags, u32 noflags,
2408 						  bool no_gw)
2409 {
2410 	struct fib6_node *fn;
2411 	struct fib6_info *rt = NULL;
2412 	struct fib6_table *table;
2413 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2414 
2415 	table = fib6_get_table(dev_net(dev), tb_id);
2416 	if (!table)
2417 		return NULL;
2418 
2419 	rcu_read_lock();
2420 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2421 	if (!fn)
2422 		goto out;
2423 
2424 	for_each_fib6_node_rt_rcu(fn) {
2425 		/* prefix routes only use builtin fib6_nh */
2426 		if (rt->nh)
2427 			continue;
2428 
2429 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2430 			continue;
2431 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2432 			continue;
2433 		if ((rt->fib6_flags & flags) != flags)
2434 			continue;
2435 		if ((rt->fib6_flags & noflags) != 0)
2436 			continue;
2437 		if (!fib6_info_hold_safe(rt))
2438 			continue;
2439 		break;
2440 	}
2441 out:
2442 	rcu_read_unlock();
2443 	return rt;
2444 }
2445 
2446 
2447 /* Create "default" multicast route to the interface */
2448 
2449 static void addrconf_add_mroute(struct net_device *dev)
2450 {
2451 	struct fib6_config cfg = {
2452 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2453 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2454 		.fc_ifindex = dev->ifindex,
2455 		.fc_dst_len = 8,
2456 		.fc_flags = RTF_UP,
2457 		.fc_type = RTN_UNICAST,
2458 		.fc_nlinfo.nl_net = dev_net(dev),
2459 	};
2460 
2461 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2462 
2463 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2464 }
2465 
2466 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2467 {
2468 	struct inet6_dev *idev;
2469 
2470 	ASSERT_RTNL();
2471 
2472 	idev = ipv6_find_idev(dev);
2473 	if (IS_ERR(idev))
2474 		return idev;
2475 
2476 	if (idev->cnf.disable_ipv6)
2477 		return ERR_PTR(-EACCES);
2478 
2479 	/* Add default multicast route */
2480 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2481 		addrconf_add_mroute(dev);
2482 
2483 	return idev;
2484 }
2485 
2486 static void manage_tempaddrs(struct inet6_dev *idev,
2487 			     struct inet6_ifaddr *ifp,
2488 			     __u32 valid_lft, __u32 prefered_lft,
2489 			     bool create, unsigned long now)
2490 {
2491 	u32 flags;
2492 	struct inet6_ifaddr *ift;
2493 
2494 	read_lock_bh(&idev->lock);
2495 	/* update all temporary addresses in the list */
2496 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2497 		int age, max_valid, max_prefered;
2498 
2499 		if (ifp != ift->ifpub)
2500 			continue;
2501 
2502 		/* RFC 4941 section 3.3:
2503 		 * If a received option will extend the lifetime of a public
2504 		 * address, the lifetimes of temporary addresses should
2505 		 * be extended, subject to the overall constraint that no
2506 		 * temporary addresses should ever remain "valid" or "preferred"
2507 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2508 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2509 		 */
2510 		age = (now - ift->cstamp) / HZ;
2511 		max_valid = idev->cnf.temp_valid_lft - age;
2512 		if (max_valid < 0)
2513 			max_valid = 0;
2514 
2515 		max_prefered = idev->cnf.temp_prefered_lft -
2516 			       idev->desync_factor - age;
2517 		if (max_prefered < 0)
2518 			max_prefered = 0;
2519 
2520 		if (valid_lft > max_valid)
2521 			valid_lft = max_valid;
2522 
2523 		if (prefered_lft > max_prefered)
2524 			prefered_lft = max_prefered;
2525 
2526 		spin_lock(&ift->lock);
2527 		flags = ift->flags;
2528 		ift->valid_lft = valid_lft;
2529 		ift->prefered_lft = prefered_lft;
2530 		ift->tstamp = now;
2531 		if (prefered_lft > 0)
2532 			ift->flags &= ~IFA_F_DEPRECATED;
2533 
2534 		spin_unlock(&ift->lock);
2535 		if (!(flags&IFA_F_TENTATIVE))
2536 			ipv6_ifa_notify(0, ift);
2537 	}
2538 
2539 	if ((create || list_empty(&idev->tempaddr_list)) &&
2540 	    idev->cnf.use_tempaddr > 0) {
2541 		/* When a new public address is created as described
2542 		 * in [ADDRCONF], also create a new temporary address.
2543 		 * Also create a temporary address if it's enabled but
2544 		 * no temporary address currently exists.
2545 		 */
2546 		read_unlock_bh(&idev->lock);
2547 		ipv6_create_tempaddr(ifp, NULL, false);
2548 	} else {
2549 		read_unlock_bh(&idev->lock);
2550 	}
2551 }
2552 
2553 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2554 {
2555 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2556 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2557 }
2558 
2559 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2560 				 const struct prefix_info *pinfo,
2561 				 struct inet6_dev *in6_dev,
2562 				 const struct in6_addr *addr, int addr_type,
2563 				 u32 addr_flags, bool sllao, bool tokenized,
2564 				 __u32 valid_lft, u32 prefered_lft)
2565 {
2566 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2567 	int create = 0, update_lft = 0;
2568 
2569 	if (!ifp && valid_lft) {
2570 		int max_addresses = in6_dev->cnf.max_addresses;
2571 		struct ifa6_config cfg = {
2572 			.pfx = addr,
2573 			.plen = pinfo->prefix_len,
2574 			.ifa_flags = addr_flags,
2575 			.valid_lft = valid_lft,
2576 			.preferred_lft = prefered_lft,
2577 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2578 		};
2579 
2580 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2581 		if ((net->ipv6.devconf_all->optimistic_dad ||
2582 		     in6_dev->cnf.optimistic_dad) &&
2583 		    !net->ipv6.devconf_all->forwarding && sllao)
2584 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2585 #endif
2586 
2587 		/* Do not allow to create too much of autoconfigured
2588 		 * addresses; this would be too easy way to crash kernel.
2589 		 */
2590 		if (!max_addresses ||
2591 		    ipv6_count_addresses(in6_dev) < max_addresses)
2592 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2593 
2594 		if (IS_ERR_OR_NULL(ifp))
2595 			return -1;
2596 
2597 		create = 1;
2598 		spin_lock_bh(&ifp->lock);
2599 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2600 		ifp->cstamp = jiffies;
2601 		ifp->tokenized = tokenized;
2602 		spin_unlock_bh(&ifp->lock);
2603 		addrconf_dad_start(ifp);
2604 	}
2605 
2606 	if (ifp) {
2607 		u32 flags;
2608 		unsigned long now;
2609 		u32 stored_lft;
2610 
2611 		/* update lifetime (RFC2462 5.5.3 e) */
2612 		spin_lock_bh(&ifp->lock);
2613 		now = jiffies;
2614 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2615 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2616 		else
2617 			stored_lft = 0;
2618 		if (!create && stored_lft) {
2619 			const u32 minimum_lft = min_t(u32,
2620 				stored_lft, MIN_VALID_LIFETIME);
2621 			valid_lft = max(valid_lft, minimum_lft);
2622 
2623 			/* RFC4862 Section 5.5.3e:
2624 			 * "Note that the preferred lifetime of the
2625 			 *  corresponding address is always reset to
2626 			 *  the Preferred Lifetime in the received
2627 			 *  Prefix Information option, regardless of
2628 			 *  whether the valid lifetime is also reset or
2629 			 *  ignored."
2630 			 *
2631 			 * So we should always update prefered_lft here.
2632 			 */
2633 			update_lft = 1;
2634 		}
2635 
2636 		if (update_lft) {
2637 			ifp->valid_lft = valid_lft;
2638 			ifp->prefered_lft = prefered_lft;
2639 			ifp->tstamp = now;
2640 			flags = ifp->flags;
2641 			ifp->flags &= ~IFA_F_DEPRECATED;
2642 			spin_unlock_bh(&ifp->lock);
2643 
2644 			if (!(flags&IFA_F_TENTATIVE))
2645 				ipv6_ifa_notify(0, ifp);
2646 		} else
2647 			spin_unlock_bh(&ifp->lock);
2648 
2649 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2650 				 create, now);
2651 
2652 		in6_ifa_put(ifp);
2653 		addrconf_verify();
2654 	}
2655 
2656 	return 0;
2657 }
2658 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2659 
2660 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2661 {
2662 	struct prefix_info *pinfo;
2663 	__u32 valid_lft;
2664 	__u32 prefered_lft;
2665 	int addr_type, err;
2666 	u32 addr_flags = 0;
2667 	struct inet6_dev *in6_dev;
2668 	struct net *net = dev_net(dev);
2669 
2670 	pinfo = (struct prefix_info *) opt;
2671 
2672 	if (len < sizeof(struct prefix_info)) {
2673 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2674 		return;
2675 	}
2676 
2677 	/*
2678 	 *	Validation checks ([ADDRCONF], page 19)
2679 	 */
2680 
2681 	addr_type = ipv6_addr_type(&pinfo->prefix);
2682 
2683 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2684 		return;
2685 
2686 	valid_lft = ntohl(pinfo->valid);
2687 	prefered_lft = ntohl(pinfo->prefered);
2688 
2689 	if (prefered_lft > valid_lft) {
2690 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2691 		return;
2692 	}
2693 
2694 	in6_dev = in6_dev_get(dev);
2695 
2696 	if (!in6_dev) {
2697 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2698 				    dev->name);
2699 		return;
2700 	}
2701 
2702 	/*
2703 	 *	Two things going on here:
2704 	 *	1) Add routes for on-link prefixes
2705 	 *	2) Configure prefixes with the auto flag set
2706 	 */
2707 
2708 	if (pinfo->onlink) {
2709 		struct fib6_info *rt;
2710 		unsigned long rt_expires;
2711 
2712 		/* Avoid arithmetic overflow. Really, we could
2713 		 * save rt_expires in seconds, likely valid_lft,
2714 		 * but it would require division in fib gc, that it
2715 		 * not good.
2716 		 */
2717 		if (HZ > USER_HZ)
2718 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2719 		else
2720 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2721 
2722 		if (addrconf_finite_timeout(rt_expires))
2723 			rt_expires *= HZ;
2724 
2725 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2726 					       pinfo->prefix_len,
2727 					       dev,
2728 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2729 					       RTF_DEFAULT, true);
2730 
2731 		if (rt) {
2732 			/* Autoconf prefix route */
2733 			if (valid_lft == 0) {
2734 				ip6_del_rt(net, rt);
2735 				rt = NULL;
2736 			} else if (addrconf_finite_timeout(rt_expires)) {
2737 				/* not infinity */
2738 				fib6_set_expires(rt, jiffies + rt_expires);
2739 			} else {
2740 				fib6_clean_expires(rt);
2741 			}
2742 		} else if (valid_lft) {
2743 			clock_t expires = 0;
2744 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2745 			if (addrconf_finite_timeout(rt_expires)) {
2746 				/* not infinity */
2747 				flags |= RTF_EXPIRES;
2748 				expires = jiffies_to_clock_t(rt_expires);
2749 			}
2750 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2751 					      0, dev, expires, flags,
2752 					      GFP_ATOMIC);
2753 		}
2754 		fib6_info_release(rt);
2755 	}
2756 
2757 	/* Try to figure out our local address for this prefix */
2758 
2759 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2760 		struct in6_addr addr;
2761 		bool tokenized = false, dev_addr_generated = false;
2762 
2763 		if (pinfo->prefix_len == 64) {
2764 			memcpy(&addr, &pinfo->prefix, 8);
2765 
2766 			if (!ipv6_addr_any(&in6_dev->token)) {
2767 				read_lock_bh(&in6_dev->lock);
2768 				memcpy(addr.s6_addr + 8,
2769 				       in6_dev->token.s6_addr + 8, 8);
2770 				read_unlock_bh(&in6_dev->lock);
2771 				tokenized = true;
2772 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2773 				   !ipv6_generate_stable_address(&addr, 0,
2774 								 in6_dev)) {
2775 				addr_flags |= IFA_F_STABLE_PRIVACY;
2776 				goto ok;
2777 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2778 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2779 				goto put;
2780 			} else {
2781 				dev_addr_generated = true;
2782 			}
2783 			goto ok;
2784 		}
2785 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2786 				    pinfo->prefix_len);
2787 		goto put;
2788 
2789 ok:
2790 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2791 						   &addr, addr_type,
2792 						   addr_flags, sllao,
2793 						   tokenized, valid_lft,
2794 						   prefered_lft);
2795 		if (err)
2796 			goto put;
2797 
2798 		/* Ignore error case here because previous prefix add addr was
2799 		 * successful which will be notified.
2800 		 */
2801 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2802 					      addr_type, addr_flags, sllao,
2803 					      tokenized, valid_lft,
2804 					      prefered_lft,
2805 					      dev_addr_generated);
2806 	}
2807 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2808 put:
2809 	in6_dev_put(in6_dev);
2810 }
2811 
2812 /*
2813  *	Set destination address.
2814  *	Special case for SIT interfaces where we create a new "virtual"
2815  *	device.
2816  */
2817 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2818 {
2819 	struct in6_ifreq ireq;
2820 	struct net_device *dev;
2821 	int err = -EINVAL;
2822 
2823 	rtnl_lock();
2824 
2825 	err = -EFAULT;
2826 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2827 		goto err_exit;
2828 
2829 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2830 
2831 	err = -ENODEV;
2832 	if (!dev)
2833 		goto err_exit;
2834 
2835 #if IS_ENABLED(CONFIG_IPV6_SIT)
2836 	if (dev->type == ARPHRD_SIT) {
2837 		const struct net_device_ops *ops = dev->netdev_ops;
2838 		struct ifreq ifr;
2839 		struct ip_tunnel_parm p;
2840 
2841 		err = -EADDRNOTAVAIL;
2842 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2843 			goto err_exit;
2844 
2845 		memset(&p, 0, sizeof(p));
2846 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2847 		p.iph.saddr = 0;
2848 		p.iph.version = 4;
2849 		p.iph.ihl = 5;
2850 		p.iph.protocol = IPPROTO_IPV6;
2851 		p.iph.ttl = 64;
2852 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2853 
2854 		if (ops->ndo_do_ioctl) {
2855 			mm_segment_t oldfs = get_fs();
2856 
2857 			set_fs(KERNEL_DS);
2858 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2859 			set_fs(oldfs);
2860 		} else
2861 			err = -EOPNOTSUPP;
2862 
2863 		if (err == 0) {
2864 			err = -ENOBUFS;
2865 			dev = __dev_get_by_name(net, p.name);
2866 			if (!dev)
2867 				goto err_exit;
2868 			err = dev_open(dev, NULL);
2869 		}
2870 	}
2871 #endif
2872 
2873 err_exit:
2874 	rtnl_unlock();
2875 	return err;
2876 }
2877 
2878 static int ipv6_mc_config(struct sock *sk, bool join,
2879 			  const struct in6_addr *addr, int ifindex)
2880 {
2881 	int ret;
2882 
2883 	ASSERT_RTNL();
2884 
2885 	lock_sock(sk);
2886 	if (join)
2887 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2888 	else
2889 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2890 	release_sock(sk);
2891 
2892 	return ret;
2893 }
2894 
2895 /*
2896  *	Manual configuration of address on an interface
2897  */
2898 static int inet6_addr_add(struct net *net, int ifindex,
2899 			  struct ifa6_config *cfg,
2900 			  struct netlink_ext_ack *extack)
2901 {
2902 	struct inet6_ifaddr *ifp;
2903 	struct inet6_dev *idev;
2904 	struct net_device *dev;
2905 	unsigned long timeout;
2906 	clock_t expires;
2907 	u32 flags;
2908 
2909 	ASSERT_RTNL();
2910 
2911 	if (cfg->plen > 128)
2912 		return -EINVAL;
2913 
2914 	/* check the lifetime */
2915 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2916 		return -EINVAL;
2917 
2918 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2919 		return -EINVAL;
2920 
2921 	dev = __dev_get_by_index(net, ifindex);
2922 	if (!dev)
2923 		return -ENODEV;
2924 
2925 	idev = addrconf_add_dev(dev);
2926 	if (IS_ERR(idev))
2927 		return PTR_ERR(idev);
2928 
2929 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2930 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2931 					 true, cfg->pfx, ifindex);
2932 
2933 		if (ret < 0)
2934 			return ret;
2935 	}
2936 
2937 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2938 
2939 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2940 	if (addrconf_finite_timeout(timeout)) {
2941 		expires = jiffies_to_clock_t(timeout * HZ);
2942 		cfg->valid_lft = timeout;
2943 		flags = RTF_EXPIRES;
2944 	} else {
2945 		expires = 0;
2946 		flags = 0;
2947 		cfg->ifa_flags |= IFA_F_PERMANENT;
2948 	}
2949 
2950 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2951 	if (addrconf_finite_timeout(timeout)) {
2952 		if (timeout == 0)
2953 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2954 		cfg->preferred_lft = timeout;
2955 	}
2956 
2957 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2958 	if (!IS_ERR(ifp)) {
2959 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2960 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2961 					      ifp->rt_priority, dev, expires,
2962 					      flags, GFP_KERNEL);
2963 		}
2964 
2965 		/* Send a netlink notification if DAD is enabled and
2966 		 * optimistic flag is not set
2967 		 */
2968 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2969 			ipv6_ifa_notify(0, ifp);
2970 		/*
2971 		 * Note that section 3.1 of RFC 4429 indicates
2972 		 * that the Optimistic flag should not be set for
2973 		 * manually configured addresses
2974 		 */
2975 		addrconf_dad_start(ifp);
2976 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2977 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2978 					 cfg->preferred_lft, true, jiffies);
2979 		in6_ifa_put(ifp);
2980 		addrconf_verify_rtnl();
2981 		return 0;
2982 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2983 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2984 			       cfg->pfx, ifindex);
2985 	}
2986 
2987 	return PTR_ERR(ifp);
2988 }
2989 
2990 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2991 			  const struct in6_addr *pfx, unsigned int plen)
2992 {
2993 	struct inet6_ifaddr *ifp;
2994 	struct inet6_dev *idev;
2995 	struct net_device *dev;
2996 
2997 	if (plen > 128)
2998 		return -EINVAL;
2999 
3000 	dev = __dev_get_by_index(net, ifindex);
3001 	if (!dev)
3002 		return -ENODEV;
3003 
3004 	idev = __in6_dev_get(dev);
3005 	if (!idev)
3006 		return -ENXIO;
3007 
3008 	read_lock_bh(&idev->lock);
3009 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3010 		if (ifp->prefix_len == plen &&
3011 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3012 			in6_ifa_hold(ifp);
3013 			read_unlock_bh(&idev->lock);
3014 
3015 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3016 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3017 				manage_tempaddrs(idev, ifp, 0, 0, false,
3018 						 jiffies);
3019 			ipv6_del_addr(ifp);
3020 			addrconf_verify_rtnl();
3021 			if (ipv6_addr_is_multicast(pfx)) {
3022 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3023 					       false, pfx, dev->ifindex);
3024 			}
3025 			return 0;
3026 		}
3027 	}
3028 	read_unlock_bh(&idev->lock);
3029 	return -EADDRNOTAVAIL;
3030 }
3031 
3032 
3033 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3034 {
3035 	struct ifa6_config cfg = {
3036 		.ifa_flags = IFA_F_PERMANENT,
3037 		.preferred_lft = INFINITY_LIFE_TIME,
3038 		.valid_lft = INFINITY_LIFE_TIME,
3039 	};
3040 	struct in6_ifreq ireq;
3041 	int err;
3042 
3043 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3044 		return -EPERM;
3045 
3046 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3047 		return -EFAULT;
3048 
3049 	cfg.pfx = &ireq.ifr6_addr;
3050 	cfg.plen = ireq.ifr6_prefixlen;
3051 
3052 	rtnl_lock();
3053 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3054 	rtnl_unlock();
3055 	return err;
3056 }
3057 
3058 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3059 {
3060 	struct in6_ifreq ireq;
3061 	int err;
3062 
3063 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3064 		return -EPERM;
3065 
3066 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3067 		return -EFAULT;
3068 
3069 	rtnl_lock();
3070 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3071 			     ireq.ifr6_prefixlen);
3072 	rtnl_unlock();
3073 	return err;
3074 }
3075 
3076 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3077 		     int plen, int scope)
3078 {
3079 	struct inet6_ifaddr *ifp;
3080 	struct ifa6_config cfg = {
3081 		.pfx = addr,
3082 		.plen = plen,
3083 		.ifa_flags = IFA_F_PERMANENT,
3084 		.valid_lft = INFINITY_LIFE_TIME,
3085 		.preferred_lft = INFINITY_LIFE_TIME,
3086 		.scope = scope
3087 	};
3088 
3089 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3090 	if (!IS_ERR(ifp)) {
3091 		spin_lock_bh(&ifp->lock);
3092 		ifp->flags &= ~IFA_F_TENTATIVE;
3093 		spin_unlock_bh(&ifp->lock);
3094 		rt_genid_bump_ipv6(dev_net(idev->dev));
3095 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3096 		in6_ifa_put(ifp);
3097 	}
3098 }
3099 
3100 #if IS_ENABLED(CONFIG_IPV6_SIT)
3101 static void sit_add_v4_addrs(struct inet6_dev *idev)
3102 {
3103 	struct in6_addr addr;
3104 	struct net_device *dev;
3105 	struct net *net = dev_net(idev->dev);
3106 	int scope, plen;
3107 	u32 pflags = 0;
3108 
3109 	ASSERT_RTNL();
3110 
3111 	memset(&addr, 0, sizeof(struct in6_addr));
3112 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3113 
3114 	if (idev->dev->flags&IFF_POINTOPOINT) {
3115 		addr.s6_addr32[0] = htonl(0xfe800000);
3116 		scope = IFA_LINK;
3117 		plen = 64;
3118 	} else {
3119 		scope = IPV6_ADDR_COMPATv4;
3120 		plen = 96;
3121 		pflags |= RTF_NONEXTHOP;
3122 	}
3123 
3124 	if (addr.s6_addr32[3]) {
3125 		add_addr(idev, &addr, plen, scope);
3126 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3127 				      GFP_KERNEL);
3128 		return;
3129 	}
3130 
3131 	for_each_netdev(net, dev) {
3132 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3133 		if (in_dev && (dev->flags & IFF_UP)) {
3134 			struct in_ifaddr *ifa;
3135 			int flag = scope;
3136 
3137 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3138 				addr.s6_addr32[3] = ifa->ifa_local;
3139 
3140 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3141 					continue;
3142 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3143 					if (idev->dev->flags&IFF_POINTOPOINT)
3144 						continue;
3145 					flag |= IFA_HOST;
3146 				}
3147 
3148 				add_addr(idev, &addr, plen, flag);
3149 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3150 						      0, pflags, GFP_KERNEL);
3151 			}
3152 		}
3153 	}
3154 }
3155 #endif
3156 
3157 static void init_loopback(struct net_device *dev)
3158 {
3159 	struct inet6_dev  *idev;
3160 
3161 	/* ::1 */
3162 
3163 	ASSERT_RTNL();
3164 
3165 	idev = ipv6_find_idev(dev);
3166 	if (IS_ERR(idev)) {
3167 		pr_debug("%s: add_dev failed\n", __func__);
3168 		return;
3169 	}
3170 
3171 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3172 }
3173 
3174 void addrconf_add_linklocal(struct inet6_dev *idev,
3175 			    const struct in6_addr *addr, u32 flags)
3176 {
3177 	struct ifa6_config cfg = {
3178 		.pfx = addr,
3179 		.plen = 64,
3180 		.ifa_flags = flags | IFA_F_PERMANENT,
3181 		.valid_lft = INFINITY_LIFE_TIME,
3182 		.preferred_lft = INFINITY_LIFE_TIME,
3183 		.scope = IFA_LINK
3184 	};
3185 	struct inet6_ifaddr *ifp;
3186 
3187 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3188 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3189 	     idev->cnf.optimistic_dad) &&
3190 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3191 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3192 #endif
3193 
3194 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3195 	if (!IS_ERR(ifp)) {
3196 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3197 				      0, 0, GFP_ATOMIC);
3198 		addrconf_dad_start(ifp);
3199 		in6_ifa_put(ifp);
3200 	}
3201 }
3202 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3203 
3204 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3205 {
3206 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3207 		return true;
3208 
3209 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3210 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3211 		return true;
3212 
3213 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3214 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3215 		return true;
3216 
3217 	return false;
3218 }
3219 
3220 static int ipv6_generate_stable_address(struct in6_addr *address,
3221 					u8 dad_count,
3222 					const struct inet6_dev *idev)
3223 {
3224 	static DEFINE_SPINLOCK(lock);
3225 	static __u32 digest[SHA_DIGEST_WORDS];
3226 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3227 
3228 	static union {
3229 		char __data[SHA_MESSAGE_BYTES];
3230 		struct {
3231 			struct in6_addr secret;
3232 			__be32 prefix[2];
3233 			unsigned char hwaddr[MAX_ADDR_LEN];
3234 			u8 dad_count;
3235 		} __packed;
3236 	} data;
3237 
3238 	struct in6_addr secret;
3239 	struct in6_addr temp;
3240 	struct net *net = dev_net(idev->dev);
3241 
3242 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3243 
3244 	if (idev->cnf.stable_secret.initialized)
3245 		secret = idev->cnf.stable_secret.secret;
3246 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3247 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3248 	else
3249 		return -1;
3250 
3251 retry:
3252 	spin_lock_bh(&lock);
3253 
3254 	sha_init(digest);
3255 	memset(&data, 0, sizeof(data));
3256 	memset(workspace, 0, sizeof(workspace));
3257 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3258 	data.prefix[0] = address->s6_addr32[0];
3259 	data.prefix[1] = address->s6_addr32[1];
3260 	data.secret = secret;
3261 	data.dad_count = dad_count;
3262 
3263 	sha_transform(digest, data.__data, workspace);
3264 
3265 	temp = *address;
3266 	temp.s6_addr32[2] = (__force __be32)digest[0];
3267 	temp.s6_addr32[3] = (__force __be32)digest[1];
3268 
3269 	spin_unlock_bh(&lock);
3270 
3271 	if (ipv6_reserved_interfaceid(temp)) {
3272 		dad_count++;
3273 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3274 			return -1;
3275 		goto retry;
3276 	}
3277 
3278 	*address = temp;
3279 	return 0;
3280 }
3281 
3282 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3283 {
3284 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3285 
3286 	if (s->initialized)
3287 		return;
3288 	s = &idev->cnf.stable_secret;
3289 	get_random_bytes(&s->secret, sizeof(s->secret));
3290 	s->initialized = true;
3291 }
3292 
3293 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3294 {
3295 	struct in6_addr addr;
3296 
3297 	/* no link local addresses on L3 master devices */
3298 	if (netif_is_l3_master(idev->dev))
3299 		return;
3300 
3301 	/* no link local addresses on devices flagged as slaves */
3302 	if (idev->dev->flags & IFF_SLAVE)
3303 		return;
3304 
3305 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3306 
3307 	switch (idev->cnf.addr_gen_mode) {
3308 	case IN6_ADDR_GEN_MODE_RANDOM:
3309 		ipv6_gen_mode_random_init(idev);
3310 		fallthrough;
3311 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3312 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3313 			addrconf_add_linklocal(idev, &addr,
3314 					       IFA_F_STABLE_PRIVACY);
3315 		else if (prefix_route)
3316 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3317 					      0, 0, GFP_KERNEL);
3318 		break;
3319 	case IN6_ADDR_GEN_MODE_EUI64:
3320 		/* addrconf_add_linklocal also adds a prefix_route and we
3321 		 * only need to care about prefix routes if ipv6_generate_eui64
3322 		 * couldn't generate one.
3323 		 */
3324 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3325 			addrconf_add_linklocal(idev, &addr, 0);
3326 		else if (prefix_route)
3327 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3328 					      0, 0, GFP_KERNEL);
3329 		break;
3330 	case IN6_ADDR_GEN_MODE_NONE:
3331 	default:
3332 		/* will not add any link local address */
3333 		break;
3334 	}
3335 }
3336 
3337 static void addrconf_dev_config(struct net_device *dev)
3338 {
3339 	struct inet6_dev *idev;
3340 
3341 	ASSERT_RTNL();
3342 
3343 	if ((dev->type != ARPHRD_ETHER) &&
3344 	    (dev->type != ARPHRD_FDDI) &&
3345 	    (dev->type != ARPHRD_ARCNET) &&
3346 	    (dev->type != ARPHRD_INFINIBAND) &&
3347 	    (dev->type != ARPHRD_IEEE1394) &&
3348 	    (dev->type != ARPHRD_TUNNEL6) &&
3349 	    (dev->type != ARPHRD_6LOWPAN) &&
3350 	    (dev->type != ARPHRD_IP6GRE) &&
3351 	    (dev->type != ARPHRD_IPGRE) &&
3352 	    (dev->type != ARPHRD_TUNNEL) &&
3353 	    (dev->type != ARPHRD_NONE) &&
3354 	    (dev->type != ARPHRD_RAWIP)) {
3355 		/* Alas, we support only Ethernet autoconfiguration. */
3356 		idev = __in6_dev_get(dev);
3357 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3358 		    dev->flags & IFF_MULTICAST)
3359 			ipv6_mc_up(idev);
3360 		return;
3361 	}
3362 
3363 	idev = addrconf_add_dev(dev);
3364 	if (IS_ERR(idev))
3365 		return;
3366 
3367 	/* this device type has no EUI support */
3368 	if (dev->type == ARPHRD_NONE &&
3369 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3370 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3371 
3372 	addrconf_addr_gen(idev, false);
3373 }
3374 
3375 #if IS_ENABLED(CONFIG_IPV6_SIT)
3376 static void addrconf_sit_config(struct net_device *dev)
3377 {
3378 	struct inet6_dev *idev;
3379 
3380 	ASSERT_RTNL();
3381 
3382 	/*
3383 	 * Configure the tunnel with one of our IPv4
3384 	 * addresses... we should configure all of
3385 	 * our v4 addrs in the tunnel
3386 	 */
3387 
3388 	idev = ipv6_find_idev(dev);
3389 	if (IS_ERR(idev)) {
3390 		pr_debug("%s: add_dev failed\n", __func__);
3391 		return;
3392 	}
3393 
3394 	if (dev->priv_flags & IFF_ISATAP) {
3395 		addrconf_addr_gen(idev, false);
3396 		return;
3397 	}
3398 
3399 	sit_add_v4_addrs(idev);
3400 
3401 	if (dev->flags&IFF_POINTOPOINT)
3402 		addrconf_add_mroute(dev);
3403 }
3404 #endif
3405 
3406 #if IS_ENABLED(CONFIG_NET_IPGRE)
3407 static void addrconf_gre_config(struct net_device *dev)
3408 {
3409 	struct inet6_dev *idev;
3410 
3411 	ASSERT_RTNL();
3412 
3413 	idev = ipv6_find_idev(dev);
3414 	if (IS_ERR(idev)) {
3415 		pr_debug("%s: add_dev failed\n", __func__);
3416 		return;
3417 	}
3418 
3419 	addrconf_addr_gen(idev, true);
3420 	if (dev->flags & IFF_POINTOPOINT)
3421 		addrconf_add_mroute(dev);
3422 }
3423 #endif
3424 
3425 static int fixup_permanent_addr(struct net *net,
3426 				struct inet6_dev *idev,
3427 				struct inet6_ifaddr *ifp)
3428 {
3429 	/* !fib6_node means the host route was removed from the
3430 	 * FIB, for example, if 'lo' device is taken down. In that
3431 	 * case regenerate the host route.
3432 	 */
3433 	if (!ifp->rt || !ifp->rt->fib6_node) {
3434 		struct fib6_info *f6i, *prev;
3435 
3436 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3437 					 GFP_ATOMIC);
3438 		if (IS_ERR(f6i))
3439 			return PTR_ERR(f6i);
3440 
3441 		/* ifp->rt can be accessed outside of rtnl */
3442 		spin_lock(&ifp->lock);
3443 		prev = ifp->rt;
3444 		ifp->rt = f6i;
3445 		spin_unlock(&ifp->lock);
3446 
3447 		fib6_info_release(prev);
3448 	}
3449 
3450 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3451 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3452 				      ifp->rt_priority, idev->dev, 0, 0,
3453 				      GFP_ATOMIC);
3454 	}
3455 
3456 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3457 		addrconf_dad_start(ifp);
3458 
3459 	return 0;
3460 }
3461 
3462 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3463 {
3464 	struct inet6_ifaddr *ifp, *tmp;
3465 	struct inet6_dev *idev;
3466 
3467 	idev = __in6_dev_get(dev);
3468 	if (!idev)
3469 		return;
3470 
3471 	write_lock_bh(&idev->lock);
3472 
3473 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3474 		if ((ifp->flags & IFA_F_PERMANENT) &&
3475 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3476 			write_unlock_bh(&idev->lock);
3477 			in6_ifa_hold(ifp);
3478 			ipv6_del_addr(ifp);
3479 			write_lock_bh(&idev->lock);
3480 
3481 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3482 					     idev->dev->name, &ifp->addr);
3483 		}
3484 	}
3485 
3486 	write_unlock_bh(&idev->lock);
3487 }
3488 
3489 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3490 			   void *ptr)
3491 {
3492 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3493 	struct netdev_notifier_change_info *change_info;
3494 	struct netdev_notifier_changeupper_info *info;
3495 	struct inet6_dev *idev = __in6_dev_get(dev);
3496 	struct net *net = dev_net(dev);
3497 	int run_pending = 0;
3498 	int err;
3499 
3500 	switch (event) {
3501 	case NETDEV_REGISTER:
3502 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3503 			idev = ipv6_add_dev(dev);
3504 			if (IS_ERR(idev))
3505 				return notifier_from_errno(PTR_ERR(idev));
3506 		}
3507 		break;
3508 
3509 	case NETDEV_CHANGEMTU:
3510 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3511 		if (dev->mtu < IPV6_MIN_MTU) {
3512 			addrconf_ifdown(dev, dev != net->loopback_dev);
3513 			break;
3514 		}
3515 
3516 		if (idev) {
3517 			rt6_mtu_change(dev, dev->mtu);
3518 			idev->cnf.mtu6 = dev->mtu;
3519 			break;
3520 		}
3521 
3522 		/* allocate new idev */
3523 		idev = ipv6_add_dev(dev);
3524 		if (IS_ERR(idev))
3525 			break;
3526 
3527 		/* device is still not ready */
3528 		if (!(idev->if_flags & IF_READY))
3529 			break;
3530 
3531 		run_pending = 1;
3532 		fallthrough;
3533 	case NETDEV_UP:
3534 	case NETDEV_CHANGE:
3535 		if (dev->flags & IFF_SLAVE)
3536 			break;
3537 
3538 		if (idev && idev->cnf.disable_ipv6)
3539 			break;
3540 
3541 		if (event == NETDEV_UP) {
3542 			/* restore routes for permanent addresses */
3543 			addrconf_permanent_addr(net, dev);
3544 
3545 			if (!addrconf_link_ready(dev)) {
3546 				/* device is not ready yet. */
3547 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3548 					 dev->name);
3549 				break;
3550 			}
3551 
3552 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3553 				idev = ipv6_add_dev(dev);
3554 
3555 			if (!IS_ERR_OR_NULL(idev)) {
3556 				idev->if_flags |= IF_READY;
3557 				run_pending = 1;
3558 			}
3559 		} else if (event == NETDEV_CHANGE) {
3560 			if (!addrconf_link_ready(dev)) {
3561 				/* device is still not ready. */
3562 				rt6_sync_down_dev(dev, event);
3563 				break;
3564 			}
3565 
3566 			if (!IS_ERR_OR_NULL(idev)) {
3567 				if (idev->if_flags & IF_READY) {
3568 					/* device is already configured -
3569 					 * but resend MLD reports, we might
3570 					 * have roamed and need to update
3571 					 * multicast snooping switches
3572 					 */
3573 					ipv6_mc_up(idev);
3574 					change_info = ptr;
3575 					if (change_info->flags_changed & IFF_NOARP)
3576 						addrconf_dad_run(idev, true);
3577 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3578 					break;
3579 				}
3580 				idev->if_flags |= IF_READY;
3581 			}
3582 
3583 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3584 				dev->name);
3585 
3586 			run_pending = 1;
3587 		}
3588 
3589 		switch (dev->type) {
3590 #if IS_ENABLED(CONFIG_IPV6_SIT)
3591 		case ARPHRD_SIT:
3592 			addrconf_sit_config(dev);
3593 			break;
3594 #endif
3595 #if IS_ENABLED(CONFIG_NET_IPGRE)
3596 		case ARPHRD_IPGRE:
3597 			addrconf_gre_config(dev);
3598 			break;
3599 #endif
3600 		case ARPHRD_LOOPBACK:
3601 			init_loopback(dev);
3602 			break;
3603 
3604 		default:
3605 			addrconf_dev_config(dev);
3606 			break;
3607 		}
3608 
3609 		if (!IS_ERR_OR_NULL(idev)) {
3610 			if (run_pending)
3611 				addrconf_dad_run(idev, false);
3612 
3613 			/* Device has an address by now */
3614 			rt6_sync_up(dev, RTNH_F_DEAD);
3615 
3616 			/*
3617 			 * If the MTU changed during the interface down,
3618 			 * when the interface up, the changed MTU must be
3619 			 * reflected in the idev as well as routers.
3620 			 */
3621 			if (idev->cnf.mtu6 != dev->mtu &&
3622 			    dev->mtu >= IPV6_MIN_MTU) {
3623 				rt6_mtu_change(dev, dev->mtu);
3624 				idev->cnf.mtu6 = dev->mtu;
3625 			}
3626 			idev->tstamp = jiffies;
3627 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3628 
3629 			/*
3630 			 * If the changed mtu during down is lower than
3631 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3632 			 */
3633 			if (dev->mtu < IPV6_MIN_MTU)
3634 				addrconf_ifdown(dev, dev != net->loopback_dev);
3635 		}
3636 		break;
3637 
3638 	case NETDEV_DOWN:
3639 	case NETDEV_UNREGISTER:
3640 		/*
3641 		 *	Remove all addresses from this interface.
3642 		 */
3643 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3644 		break;
3645 
3646 	case NETDEV_CHANGENAME:
3647 		if (idev) {
3648 			snmp6_unregister_dev(idev);
3649 			addrconf_sysctl_unregister(idev);
3650 			err = addrconf_sysctl_register(idev);
3651 			if (err)
3652 				return notifier_from_errno(err);
3653 			err = snmp6_register_dev(idev);
3654 			if (err) {
3655 				addrconf_sysctl_unregister(idev);
3656 				return notifier_from_errno(err);
3657 			}
3658 		}
3659 		break;
3660 
3661 	case NETDEV_PRE_TYPE_CHANGE:
3662 	case NETDEV_POST_TYPE_CHANGE:
3663 		if (idev)
3664 			addrconf_type_change(dev, event);
3665 		break;
3666 
3667 	case NETDEV_CHANGEUPPER:
3668 		info = ptr;
3669 
3670 		/* flush all routes if dev is linked to or unlinked from
3671 		 * an L3 master device (e.g., VRF)
3672 		 */
3673 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3674 			addrconf_ifdown(dev, 0);
3675 	}
3676 
3677 	return NOTIFY_OK;
3678 }
3679 
3680 /*
3681  *	addrconf module should be notified of a device going up
3682  */
3683 static struct notifier_block ipv6_dev_notf = {
3684 	.notifier_call = addrconf_notify,
3685 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3686 };
3687 
3688 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3689 {
3690 	struct inet6_dev *idev;
3691 	ASSERT_RTNL();
3692 
3693 	idev = __in6_dev_get(dev);
3694 
3695 	if (event == NETDEV_POST_TYPE_CHANGE)
3696 		ipv6_mc_remap(idev);
3697 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3698 		ipv6_mc_unmap(idev);
3699 }
3700 
3701 static bool addr_is_local(const struct in6_addr *addr)
3702 {
3703 	return ipv6_addr_type(addr) &
3704 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3705 }
3706 
3707 static int addrconf_ifdown(struct net_device *dev, int how)
3708 {
3709 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3710 	struct net *net = dev_net(dev);
3711 	struct inet6_dev *idev;
3712 	struct inet6_ifaddr *ifa, *tmp;
3713 	bool keep_addr = false;
3714 	int state, i;
3715 
3716 	ASSERT_RTNL();
3717 
3718 	rt6_disable_ip(dev, event);
3719 
3720 	idev = __in6_dev_get(dev);
3721 	if (!idev)
3722 		return -ENODEV;
3723 
3724 	/*
3725 	 * Step 1: remove reference to ipv6 device from parent device.
3726 	 *	   Do not dev_put!
3727 	 */
3728 	if (how) {
3729 		idev->dead = 1;
3730 
3731 		/* protected by rtnl_lock */
3732 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3733 
3734 		/* Step 1.5: remove snmp6 entry */
3735 		snmp6_unregister_dev(idev);
3736 
3737 	}
3738 
3739 	/* combine the user config with event to determine if permanent
3740 	 * addresses are to be removed from address hash table
3741 	 */
3742 	if (!how && !idev->cnf.disable_ipv6) {
3743 		/* aggregate the system setting and interface setting */
3744 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3745 
3746 		if (!_keep_addr)
3747 			_keep_addr = idev->cnf.keep_addr_on_down;
3748 
3749 		keep_addr = (_keep_addr > 0);
3750 	}
3751 
3752 	/* Step 2: clear hash table */
3753 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3754 		struct hlist_head *h = &inet6_addr_lst[i];
3755 
3756 		spin_lock_bh(&addrconf_hash_lock);
3757 restart:
3758 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3759 			if (ifa->idev == idev) {
3760 				addrconf_del_dad_work(ifa);
3761 				/* combined flag + permanent flag decide if
3762 				 * address is retained on a down event
3763 				 */
3764 				if (!keep_addr ||
3765 				    !(ifa->flags & IFA_F_PERMANENT) ||
3766 				    addr_is_local(&ifa->addr)) {
3767 					hlist_del_init_rcu(&ifa->addr_lst);
3768 					goto restart;
3769 				}
3770 			}
3771 		}
3772 		spin_unlock_bh(&addrconf_hash_lock);
3773 	}
3774 
3775 	write_lock_bh(&idev->lock);
3776 
3777 	addrconf_del_rs_timer(idev);
3778 
3779 	/* Step 2: clear flags for stateless addrconf */
3780 	if (!how)
3781 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3782 
3783 	/* Step 3: clear tempaddr list */
3784 	while (!list_empty(&idev->tempaddr_list)) {
3785 		ifa = list_first_entry(&idev->tempaddr_list,
3786 				       struct inet6_ifaddr, tmp_list);
3787 		list_del(&ifa->tmp_list);
3788 		write_unlock_bh(&idev->lock);
3789 		spin_lock_bh(&ifa->lock);
3790 
3791 		if (ifa->ifpub) {
3792 			in6_ifa_put(ifa->ifpub);
3793 			ifa->ifpub = NULL;
3794 		}
3795 		spin_unlock_bh(&ifa->lock);
3796 		in6_ifa_put(ifa);
3797 		write_lock_bh(&idev->lock);
3798 	}
3799 
3800 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3801 		struct fib6_info *rt = NULL;
3802 		bool keep;
3803 
3804 		addrconf_del_dad_work(ifa);
3805 
3806 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3807 			!addr_is_local(&ifa->addr);
3808 
3809 		write_unlock_bh(&idev->lock);
3810 		spin_lock_bh(&ifa->lock);
3811 
3812 		if (keep) {
3813 			/* set state to skip the notifier below */
3814 			state = INET6_IFADDR_STATE_DEAD;
3815 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3816 			if (!(ifa->flags & IFA_F_NODAD))
3817 				ifa->flags |= IFA_F_TENTATIVE;
3818 
3819 			rt = ifa->rt;
3820 			ifa->rt = NULL;
3821 		} else {
3822 			state = ifa->state;
3823 			ifa->state = INET6_IFADDR_STATE_DEAD;
3824 		}
3825 
3826 		spin_unlock_bh(&ifa->lock);
3827 
3828 		if (rt)
3829 			ip6_del_rt(net, rt);
3830 
3831 		if (state != INET6_IFADDR_STATE_DEAD) {
3832 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3833 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3834 		} else {
3835 			if (idev->cnf.forwarding)
3836 				addrconf_leave_anycast(ifa);
3837 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3838 		}
3839 
3840 		write_lock_bh(&idev->lock);
3841 		if (!keep) {
3842 			list_del_rcu(&ifa->if_list);
3843 			in6_ifa_put(ifa);
3844 		}
3845 	}
3846 
3847 	write_unlock_bh(&idev->lock);
3848 
3849 	/* Step 5: Discard anycast and multicast list */
3850 	if (how) {
3851 		ipv6_ac_destroy_dev(idev);
3852 		ipv6_mc_destroy_dev(idev);
3853 	} else {
3854 		ipv6_mc_down(idev);
3855 	}
3856 
3857 	idev->tstamp = jiffies;
3858 
3859 	/* Last: Shot the device (if unregistered) */
3860 	if (how) {
3861 		addrconf_sysctl_unregister(idev);
3862 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3863 		neigh_ifdown(&nd_tbl, dev);
3864 		in6_dev_put(idev);
3865 	}
3866 	return 0;
3867 }
3868 
3869 static void addrconf_rs_timer(struct timer_list *t)
3870 {
3871 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3872 	struct net_device *dev = idev->dev;
3873 	struct in6_addr lladdr;
3874 
3875 	write_lock(&idev->lock);
3876 	if (idev->dead || !(idev->if_flags & IF_READY))
3877 		goto out;
3878 
3879 	if (!ipv6_accept_ra(idev))
3880 		goto out;
3881 
3882 	/* Announcement received after solicitation was sent */
3883 	if (idev->if_flags & IF_RA_RCVD)
3884 		goto out;
3885 
3886 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3887 		write_unlock(&idev->lock);
3888 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3889 			ndisc_send_rs(dev, &lladdr,
3890 				      &in6addr_linklocal_allrouters);
3891 		else
3892 			goto put;
3893 
3894 		write_lock(&idev->lock);
3895 		idev->rs_interval = rfc3315_s14_backoff_update(
3896 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3897 		/* The wait after the last probe can be shorter */
3898 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3899 					     idev->cnf.rtr_solicits) ?
3900 				      idev->cnf.rtr_solicit_delay :
3901 				      idev->rs_interval);
3902 	} else {
3903 		/*
3904 		 * Note: we do not support deprecated "all on-link"
3905 		 * assumption any longer.
3906 		 */
3907 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3908 	}
3909 
3910 out:
3911 	write_unlock(&idev->lock);
3912 put:
3913 	in6_dev_put(idev);
3914 }
3915 
3916 /*
3917  *	Duplicate Address Detection
3918  */
3919 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3920 {
3921 	unsigned long rand_num;
3922 	struct inet6_dev *idev = ifp->idev;
3923 	u64 nonce;
3924 
3925 	if (ifp->flags & IFA_F_OPTIMISTIC)
3926 		rand_num = 0;
3927 	else
3928 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3929 
3930 	nonce = 0;
3931 	if (idev->cnf.enhanced_dad ||
3932 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3933 		do
3934 			get_random_bytes(&nonce, 6);
3935 		while (nonce == 0);
3936 	}
3937 	ifp->dad_nonce = nonce;
3938 	ifp->dad_probes = idev->cnf.dad_transmits;
3939 	addrconf_mod_dad_work(ifp, rand_num);
3940 }
3941 
3942 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3943 {
3944 	struct inet6_dev *idev = ifp->idev;
3945 	struct net_device *dev = idev->dev;
3946 	bool bump_id, notify = false;
3947 	struct net *net;
3948 
3949 	addrconf_join_solict(dev, &ifp->addr);
3950 
3951 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3952 
3953 	read_lock_bh(&idev->lock);
3954 	spin_lock(&ifp->lock);
3955 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3956 		goto out;
3957 
3958 	net = dev_net(dev);
3959 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3960 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3961 	     idev->cnf.accept_dad < 1) ||
3962 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3963 	    ifp->flags & IFA_F_NODAD) {
3964 		bool send_na = false;
3965 
3966 		if (ifp->flags & IFA_F_TENTATIVE &&
3967 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3968 			send_na = true;
3969 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3970 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3971 		spin_unlock(&ifp->lock);
3972 		read_unlock_bh(&idev->lock);
3973 
3974 		addrconf_dad_completed(ifp, bump_id, send_na);
3975 		return;
3976 	}
3977 
3978 	if (!(idev->if_flags & IF_READY)) {
3979 		spin_unlock(&ifp->lock);
3980 		read_unlock_bh(&idev->lock);
3981 		/*
3982 		 * If the device is not ready:
3983 		 * - keep it tentative if it is a permanent address.
3984 		 * - otherwise, kill it.
3985 		 */
3986 		in6_ifa_hold(ifp);
3987 		addrconf_dad_stop(ifp, 0);
3988 		return;
3989 	}
3990 
3991 	/*
3992 	 * Optimistic nodes can start receiving
3993 	 * Frames right away
3994 	 */
3995 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3996 		ip6_ins_rt(net, ifp->rt);
3997 		if (ipv6_use_optimistic_addr(net, idev)) {
3998 			/* Because optimistic nodes can use this address,
3999 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4000 			 */
4001 			notify = true;
4002 		}
4003 	}
4004 
4005 	addrconf_dad_kick(ifp);
4006 out:
4007 	spin_unlock(&ifp->lock);
4008 	read_unlock_bh(&idev->lock);
4009 	if (notify)
4010 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4011 }
4012 
4013 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4014 {
4015 	bool begin_dad = false;
4016 
4017 	spin_lock_bh(&ifp->lock);
4018 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4019 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4020 		begin_dad = true;
4021 	}
4022 	spin_unlock_bh(&ifp->lock);
4023 
4024 	if (begin_dad)
4025 		addrconf_mod_dad_work(ifp, 0);
4026 }
4027 
4028 static void addrconf_dad_work(struct work_struct *w)
4029 {
4030 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4031 						struct inet6_ifaddr,
4032 						dad_work);
4033 	struct inet6_dev *idev = ifp->idev;
4034 	bool bump_id, disable_ipv6 = false;
4035 	struct in6_addr mcaddr;
4036 
4037 	enum {
4038 		DAD_PROCESS,
4039 		DAD_BEGIN,
4040 		DAD_ABORT,
4041 	} action = DAD_PROCESS;
4042 
4043 	rtnl_lock();
4044 
4045 	spin_lock_bh(&ifp->lock);
4046 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4047 		action = DAD_BEGIN;
4048 		ifp->state = INET6_IFADDR_STATE_DAD;
4049 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4050 		action = DAD_ABORT;
4051 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4052 
4053 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4054 		     idev->cnf.accept_dad > 1) &&
4055 		    !idev->cnf.disable_ipv6 &&
4056 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4057 			struct in6_addr addr;
4058 
4059 			addr.s6_addr32[0] = htonl(0xfe800000);
4060 			addr.s6_addr32[1] = 0;
4061 
4062 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4063 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4064 				/* DAD failed for link-local based on MAC */
4065 				idev->cnf.disable_ipv6 = 1;
4066 
4067 				pr_info("%s: IPv6 being disabled!\n",
4068 					ifp->idev->dev->name);
4069 				disable_ipv6 = true;
4070 			}
4071 		}
4072 	}
4073 	spin_unlock_bh(&ifp->lock);
4074 
4075 	if (action == DAD_BEGIN) {
4076 		addrconf_dad_begin(ifp);
4077 		goto out;
4078 	} else if (action == DAD_ABORT) {
4079 		in6_ifa_hold(ifp);
4080 		addrconf_dad_stop(ifp, 1);
4081 		if (disable_ipv6)
4082 			addrconf_ifdown(idev->dev, 0);
4083 		goto out;
4084 	}
4085 
4086 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4087 		goto out;
4088 
4089 	write_lock_bh(&idev->lock);
4090 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4091 		write_unlock_bh(&idev->lock);
4092 		goto out;
4093 	}
4094 
4095 	spin_lock(&ifp->lock);
4096 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4097 		spin_unlock(&ifp->lock);
4098 		write_unlock_bh(&idev->lock);
4099 		goto out;
4100 	}
4101 
4102 	if (ifp->dad_probes == 0) {
4103 		bool send_na = false;
4104 
4105 		/*
4106 		 * DAD was successful
4107 		 */
4108 
4109 		if (ifp->flags & IFA_F_TENTATIVE &&
4110 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4111 			send_na = true;
4112 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4113 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4114 		spin_unlock(&ifp->lock);
4115 		write_unlock_bh(&idev->lock);
4116 
4117 		addrconf_dad_completed(ifp, bump_id, send_na);
4118 
4119 		goto out;
4120 	}
4121 
4122 	ifp->dad_probes--;
4123 	addrconf_mod_dad_work(ifp,
4124 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4125 				  HZ/100));
4126 	spin_unlock(&ifp->lock);
4127 	write_unlock_bh(&idev->lock);
4128 
4129 	/* send a neighbour solicitation for our addr */
4130 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4131 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4132 		      ifp->dad_nonce);
4133 out:
4134 	in6_ifa_put(ifp);
4135 	rtnl_unlock();
4136 }
4137 
4138 /* ifp->idev must be at least read locked */
4139 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4140 {
4141 	struct inet6_ifaddr *ifpiter;
4142 	struct inet6_dev *idev = ifp->idev;
4143 
4144 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4145 		if (ifpiter->scope > IFA_LINK)
4146 			break;
4147 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4148 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4149 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4150 		    IFA_F_PERMANENT)
4151 			return false;
4152 	}
4153 	return true;
4154 }
4155 
4156 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4157 				   bool send_na)
4158 {
4159 	struct net_device *dev = ifp->idev->dev;
4160 	struct in6_addr lladdr;
4161 	bool send_rs, send_mld;
4162 
4163 	addrconf_del_dad_work(ifp);
4164 
4165 	/*
4166 	 *	Configure the address for reception. Now it is valid.
4167 	 */
4168 
4169 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4170 
4171 	/* If added prefix is link local and we are prepared to process
4172 	   router advertisements, start sending router solicitations.
4173 	 */
4174 
4175 	read_lock_bh(&ifp->idev->lock);
4176 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4177 	send_rs = send_mld &&
4178 		  ipv6_accept_ra(ifp->idev) &&
4179 		  ifp->idev->cnf.rtr_solicits != 0 &&
4180 		  (dev->flags&IFF_LOOPBACK) == 0;
4181 	read_unlock_bh(&ifp->idev->lock);
4182 
4183 	/* While dad is in progress mld report's source address is in6_addrany.
4184 	 * Resend with proper ll now.
4185 	 */
4186 	if (send_mld)
4187 		ipv6_mc_dad_complete(ifp->idev);
4188 
4189 	/* send unsolicited NA if enabled */
4190 	if (send_na &&
4191 	    (ifp->idev->cnf.ndisc_notify ||
4192 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4193 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4194 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4195 			      /*solicited=*/ false, /*override=*/ true,
4196 			      /*inc_opt=*/ true);
4197 	}
4198 
4199 	if (send_rs) {
4200 		/*
4201 		 *	If a host as already performed a random delay
4202 		 *	[...] as part of DAD [...] there is no need
4203 		 *	to delay again before sending the first RS
4204 		 */
4205 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4206 			return;
4207 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4208 
4209 		write_lock_bh(&ifp->idev->lock);
4210 		spin_lock(&ifp->lock);
4211 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4212 			ifp->idev->cnf.rtr_solicit_interval);
4213 		ifp->idev->rs_probes = 1;
4214 		ifp->idev->if_flags |= IF_RS_SENT;
4215 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4216 		spin_unlock(&ifp->lock);
4217 		write_unlock_bh(&ifp->idev->lock);
4218 	}
4219 
4220 	if (bump_id)
4221 		rt_genid_bump_ipv6(dev_net(dev));
4222 
4223 	/* Make sure that a new temporary address will be created
4224 	 * before this temporary address becomes deprecated.
4225 	 */
4226 	if (ifp->flags & IFA_F_TEMPORARY)
4227 		addrconf_verify_rtnl();
4228 }
4229 
4230 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4231 {
4232 	struct inet6_ifaddr *ifp;
4233 
4234 	read_lock_bh(&idev->lock);
4235 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4236 		spin_lock(&ifp->lock);
4237 		if ((ifp->flags & IFA_F_TENTATIVE &&
4238 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4239 			if (restart)
4240 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4241 			addrconf_dad_kick(ifp);
4242 		}
4243 		spin_unlock(&ifp->lock);
4244 	}
4245 	read_unlock_bh(&idev->lock);
4246 }
4247 
4248 #ifdef CONFIG_PROC_FS
4249 struct if6_iter_state {
4250 	struct seq_net_private p;
4251 	int bucket;
4252 	int offset;
4253 };
4254 
4255 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4256 {
4257 	struct if6_iter_state *state = seq->private;
4258 	struct net *net = seq_file_net(seq);
4259 	struct inet6_ifaddr *ifa = NULL;
4260 	int p = 0;
4261 
4262 	/* initial bucket if pos is 0 */
4263 	if (pos == 0) {
4264 		state->bucket = 0;
4265 		state->offset = 0;
4266 	}
4267 
4268 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4269 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4270 					 addr_lst) {
4271 			if (!net_eq(dev_net(ifa->idev->dev), net))
4272 				continue;
4273 			/* sync with offset */
4274 			if (p < state->offset) {
4275 				p++;
4276 				continue;
4277 			}
4278 			return ifa;
4279 		}
4280 
4281 		/* prepare for next bucket */
4282 		state->offset = 0;
4283 		p = 0;
4284 	}
4285 	return NULL;
4286 }
4287 
4288 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4289 					 struct inet6_ifaddr *ifa)
4290 {
4291 	struct if6_iter_state *state = seq->private;
4292 	struct net *net = seq_file_net(seq);
4293 
4294 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4295 		if (!net_eq(dev_net(ifa->idev->dev), net))
4296 			continue;
4297 		state->offset++;
4298 		return ifa;
4299 	}
4300 
4301 	state->offset = 0;
4302 	while (++state->bucket < IN6_ADDR_HSIZE) {
4303 		hlist_for_each_entry_rcu(ifa,
4304 				     &inet6_addr_lst[state->bucket], addr_lst) {
4305 			if (!net_eq(dev_net(ifa->idev->dev), net))
4306 				continue;
4307 			return ifa;
4308 		}
4309 	}
4310 
4311 	return NULL;
4312 }
4313 
4314 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4315 	__acquires(rcu)
4316 {
4317 	rcu_read_lock();
4318 	return if6_get_first(seq, *pos);
4319 }
4320 
4321 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4322 {
4323 	struct inet6_ifaddr *ifa;
4324 
4325 	ifa = if6_get_next(seq, v);
4326 	++*pos;
4327 	return ifa;
4328 }
4329 
4330 static void if6_seq_stop(struct seq_file *seq, void *v)
4331 	__releases(rcu)
4332 {
4333 	rcu_read_unlock();
4334 }
4335 
4336 static int if6_seq_show(struct seq_file *seq, void *v)
4337 {
4338 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4339 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4340 		   &ifp->addr,
4341 		   ifp->idev->dev->ifindex,
4342 		   ifp->prefix_len,
4343 		   ifp->scope,
4344 		   (u8) ifp->flags,
4345 		   ifp->idev->dev->name);
4346 	return 0;
4347 }
4348 
4349 static const struct seq_operations if6_seq_ops = {
4350 	.start	= if6_seq_start,
4351 	.next	= if6_seq_next,
4352 	.show	= if6_seq_show,
4353 	.stop	= if6_seq_stop,
4354 };
4355 
4356 static int __net_init if6_proc_net_init(struct net *net)
4357 {
4358 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4359 			sizeof(struct if6_iter_state)))
4360 		return -ENOMEM;
4361 	return 0;
4362 }
4363 
4364 static void __net_exit if6_proc_net_exit(struct net *net)
4365 {
4366 	remove_proc_entry("if_inet6", net->proc_net);
4367 }
4368 
4369 static struct pernet_operations if6_proc_net_ops = {
4370 	.init = if6_proc_net_init,
4371 	.exit = if6_proc_net_exit,
4372 };
4373 
4374 int __init if6_proc_init(void)
4375 {
4376 	return register_pernet_subsys(&if6_proc_net_ops);
4377 }
4378 
4379 void if6_proc_exit(void)
4380 {
4381 	unregister_pernet_subsys(&if6_proc_net_ops);
4382 }
4383 #endif	/* CONFIG_PROC_FS */
4384 
4385 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4386 /* Check if address is a home address configured on any interface. */
4387 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4388 {
4389 	unsigned int hash = inet6_addr_hash(net, addr);
4390 	struct inet6_ifaddr *ifp = NULL;
4391 	int ret = 0;
4392 
4393 	rcu_read_lock();
4394 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4395 		if (!net_eq(dev_net(ifp->idev->dev), net))
4396 			continue;
4397 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4398 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4399 			ret = 1;
4400 			break;
4401 		}
4402 	}
4403 	rcu_read_unlock();
4404 	return ret;
4405 }
4406 #endif
4407 
4408 /* RFC6554 has some algorithm to avoid loops in segment routing by
4409  * checking if the segments contains any of a local interface address.
4410  *
4411  * Quote:
4412  *
4413  * To detect loops in the SRH, a router MUST determine if the SRH
4414  * includes multiple addresses assigned to any interface on that router.
4415  * If such addresses appear more than once and are separated by at least
4416  * one address not assigned to that router.
4417  */
4418 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4419 			  unsigned char nsegs)
4420 {
4421 	const struct in6_addr *addr;
4422 	int i, ret = 0, found = 0;
4423 	struct inet6_ifaddr *ifp;
4424 	bool separated = false;
4425 	unsigned int hash;
4426 	bool hash_found;
4427 
4428 	rcu_read_lock();
4429 	for (i = 0; i < nsegs; i++) {
4430 		addr = &segs[i];
4431 		hash = inet6_addr_hash(net, addr);
4432 
4433 		hash_found = false;
4434 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4435 			if (!net_eq(dev_net(ifp->idev->dev), net))
4436 				continue;
4437 
4438 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4439 				hash_found = true;
4440 				break;
4441 			}
4442 		}
4443 
4444 		if (hash_found) {
4445 			if (found > 1 && separated) {
4446 				ret = 1;
4447 				break;
4448 			}
4449 
4450 			separated = false;
4451 			found++;
4452 		} else {
4453 			separated = true;
4454 		}
4455 	}
4456 	rcu_read_unlock();
4457 
4458 	return ret;
4459 }
4460 
4461 /*
4462  *	Periodic address status verification
4463  */
4464 
4465 static void addrconf_verify_rtnl(void)
4466 {
4467 	unsigned long now, next, next_sec, next_sched;
4468 	struct inet6_ifaddr *ifp;
4469 	int i;
4470 
4471 	ASSERT_RTNL();
4472 
4473 	rcu_read_lock_bh();
4474 	now = jiffies;
4475 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4476 
4477 	cancel_delayed_work(&addr_chk_work);
4478 
4479 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4480 restart:
4481 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4482 			unsigned long age;
4483 
4484 			/* When setting preferred_lft to a value not zero or
4485 			 * infinity, while valid_lft is infinity
4486 			 * IFA_F_PERMANENT has a non-infinity life time.
4487 			 */
4488 			if ((ifp->flags & IFA_F_PERMANENT) &&
4489 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4490 				continue;
4491 
4492 			spin_lock(&ifp->lock);
4493 			/* We try to batch several events at once. */
4494 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4495 
4496 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4497 			    age >= ifp->valid_lft) {
4498 				spin_unlock(&ifp->lock);
4499 				in6_ifa_hold(ifp);
4500 				ipv6_del_addr(ifp);
4501 				goto restart;
4502 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4503 				spin_unlock(&ifp->lock);
4504 				continue;
4505 			} else if (age >= ifp->prefered_lft) {
4506 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4507 				int deprecate = 0;
4508 
4509 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4510 					deprecate = 1;
4511 					ifp->flags |= IFA_F_DEPRECATED;
4512 				}
4513 
4514 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4515 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4516 					next = ifp->tstamp + ifp->valid_lft * HZ;
4517 
4518 				spin_unlock(&ifp->lock);
4519 
4520 				if (deprecate) {
4521 					in6_ifa_hold(ifp);
4522 
4523 					ipv6_ifa_notify(0, ifp);
4524 					in6_ifa_put(ifp);
4525 					goto restart;
4526 				}
4527 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4528 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4529 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4530 					ifp->idev->cnf.dad_transmits *
4531 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4532 
4533 				if (age >= ifp->prefered_lft - regen_advance) {
4534 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4535 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4536 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4537 					if (!ifp->regen_count && ifpub) {
4538 						ifp->regen_count++;
4539 						in6_ifa_hold(ifp);
4540 						in6_ifa_hold(ifpub);
4541 						spin_unlock(&ifp->lock);
4542 
4543 						spin_lock(&ifpub->lock);
4544 						ifpub->regen_count = 0;
4545 						spin_unlock(&ifpub->lock);
4546 						rcu_read_unlock_bh();
4547 						ipv6_create_tempaddr(ifpub, ifp, true);
4548 						in6_ifa_put(ifpub);
4549 						in6_ifa_put(ifp);
4550 						rcu_read_lock_bh();
4551 						goto restart;
4552 					}
4553 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4554 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4555 				spin_unlock(&ifp->lock);
4556 			} else {
4557 				/* ifp->prefered_lft <= ifp->valid_lft */
4558 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4559 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4560 				spin_unlock(&ifp->lock);
4561 			}
4562 		}
4563 	}
4564 
4565 	next_sec = round_jiffies_up(next);
4566 	next_sched = next;
4567 
4568 	/* If rounded timeout is accurate enough, accept it. */
4569 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4570 		next_sched = next_sec;
4571 
4572 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4573 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4574 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4575 
4576 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4577 		 now, next, next_sec, next_sched);
4578 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4579 	rcu_read_unlock_bh();
4580 }
4581 
4582 static void addrconf_verify_work(struct work_struct *w)
4583 {
4584 	rtnl_lock();
4585 	addrconf_verify_rtnl();
4586 	rtnl_unlock();
4587 }
4588 
4589 static void addrconf_verify(void)
4590 {
4591 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4592 }
4593 
4594 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4595 				     struct in6_addr **peer_pfx)
4596 {
4597 	struct in6_addr *pfx = NULL;
4598 
4599 	*peer_pfx = NULL;
4600 
4601 	if (addr)
4602 		pfx = nla_data(addr);
4603 
4604 	if (local) {
4605 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4606 			*peer_pfx = pfx;
4607 		pfx = nla_data(local);
4608 	}
4609 
4610 	return pfx;
4611 }
4612 
4613 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4614 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4615 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4616 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4617 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4618 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4619 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4620 };
4621 
4622 static int
4623 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4624 		  struct netlink_ext_ack *extack)
4625 {
4626 	struct net *net = sock_net(skb->sk);
4627 	struct ifaddrmsg *ifm;
4628 	struct nlattr *tb[IFA_MAX+1];
4629 	struct in6_addr *pfx, *peer_pfx;
4630 	u32 ifa_flags;
4631 	int err;
4632 
4633 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4634 				     ifa_ipv6_policy, extack);
4635 	if (err < 0)
4636 		return err;
4637 
4638 	ifm = nlmsg_data(nlh);
4639 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4640 	if (!pfx)
4641 		return -EINVAL;
4642 
4643 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4644 
4645 	/* We ignore other flags so far. */
4646 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4647 
4648 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4649 			      ifm->ifa_prefixlen);
4650 }
4651 
4652 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4653 			       unsigned long expires, u32 flags,
4654 			       bool modify_peer)
4655 {
4656 	struct fib6_info *f6i;
4657 	u32 prio;
4658 
4659 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4660 					ifp->prefix_len,
4661 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4662 	if (!f6i)
4663 		return -ENOENT;
4664 
4665 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4666 	if (f6i->fib6_metric != prio) {
4667 		/* delete old one */
4668 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4669 
4670 		/* add new one */
4671 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4672 				      ifp->prefix_len,
4673 				      ifp->rt_priority, ifp->idev->dev,
4674 				      expires, flags, GFP_KERNEL);
4675 	} else {
4676 		if (!expires)
4677 			fib6_clean_expires(f6i);
4678 		else
4679 			fib6_set_expires(f6i, expires);
4680 
4681 		fib6_info_release(f6i);
4682 	}
4683 
4684 	return 0;
4685 }
4686 
4687 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4688 {
4689 	u32 flags;
4690 	clock_t expires;
4691 	unsigned long timeout;
4692 	bool was_managetempaddr;
4693 	bool had_prefixroute;
4694 	bool new_peer = false;
4695 
4696 	ASSERT_RTNL();
4697 
4698 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4699 		return -EINVAL;
4700 
4701 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4702 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4703 		return -EINVAL;
4704 
4705 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4706 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4707 
4708 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4709 	if (addrconf_finite_timeout(timeout)) {
4710 		expires = jiffies_to_clock_t(timeout * HZ);
4711 		cfg->valid_lft = timeout;
4712 		flags = RTF_EXPIRES;
4713 	} else {
4714 		expires = 0;
4715 		flags = 0;
4716 		cfg->ifa_flags |= IFA_F_PERMANENT;
4717 	}
4718 
4719 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4720 	if (addrconf_finite_timeout(timeout)) {
4721 		if (timeout == 0)
4722 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4723 		cfg->preferred_lft = timeout;
4724 	}
4725 
4726 	if (cfg->peer_pfx &&
4727 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4728 		if (!ipv6_addr_any(&ifp->peer_addr))
4729 			cleanup_prefix_route(ifp, expires, true, true);
4730 		new_peer = true;
4731 	}
4732 
4733 	spin_lock_bh(&ifp->lock);
4734 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4735 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4736 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4737 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4738 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4739 			IFA_F_NOPREFIXROUTE);
4740 	ifp->flags |= cfg->ifa_flags;
4741 	ifp->tstamp = jiffies;
4742 	ifp->valid_lft = cfg->valid_lft;
4743 	ifp->prefered_lft = cfg->preferred_lft;
4744 
4745 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4746 		ifp->rt_priority = cfg->rt_priority;
4747 
4748 	if (new_peer)
4749 		ifp->peer_addr = *cfg->peer_pfx;
4750 
4751 	spin_unlock_bh(&ifp->lock);
4752 	if (!(ifp->flags&IFA_F_TENTATIVE))
4753 		ipv6_ifa_notify(0, ifp);
4754 
4755 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4756 		int rc = -ENOENT;
4757 
4758 		if (had_prefixroute)
4759 			rc = modify_prefix_route(ifp, expires, flags, false);
4760 
4761 		/* prefix route could have been deleted; if so restore it */
4762 		if (rc == -ENOENT) {
4763 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4764 					      ifp->rt_priority, ifp->idev->dev,
4765 					      expires, flags, GFP_KERNEL);
4766 		}
4767 
4768 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4769 			rc = modify_prefix_route(ifp, expires, flags, true);
4770 
4771 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4772 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4773 					      ifp->rt_priority, ifp->idev->dev,
4774 					      expires, flags, GFP_KERNEL);
4775 		}
4776 	} else if (had_prefixroute) {
4777 		enum cleanup_prefix_rt_t action;
4778 		unsigned long rt_expires;
4779 
4780 		write_lock_bh(&ifp->idev->lock);
4781 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4782 		write_unlock_bh(&ifp->idev->lock);
4783 
4784 		if (action != CLEANUP_PREFIX_RT_NOP) {
4785 			cleanup_prefix_route(ifp, rt_expires,
4786 				action == CLEANUP_PREFIX_RT_DEL, false);
4787 		}
4788 	}
4789 
4790 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4791 		if (was_managetempaddr &&
4792 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4793 			cfg->valid_lft = 0;
4794 			cfg->preferred_lft = 0;
4795 		}
4796 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4797 				 cfg->preferred_lft, !was_managetempaddr,
4798 				 jiffies);
4799 	}
4800 
4801 	addrconf_verify_rtnl();
4802 
4803 	return 0;
4804 }
4805 
4806 static int
4807 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4808 		  struct netlink_ext_ack *extack)
4809 {
4810 	struct net *net = sock_net(skb->sk);
4811 	struct ifaddrmsg *ifm;
4812 	struct nlattr *tb[IFA_MAX+1];
4813 	struct in6_addr *peer_pfx;
4814 	struct inet6_ifaddr *ifa;
4815 	struct net_device *dev;
4816 	struct inet6_dev *idev;
4817 	struct ifa6_config cfg;
4818 	int err;
4819 
4820 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4821 				     ifa_ipv6_policy, extack);
4822 	if (err < 0)
4823 		return err;
4824 
4825 	memset(&cfg, 0, sizeof(cfg));
4826 
4827 	ifm = nlmsg_data(nlh);
4828 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4829 	if (!cfg.pfx)
4830 		return -EINVAL;
4831 
4832 	cfg.peer_pfx = peer_pfx;
4833 	cfg.plen = ifm->ifa_prefixlen;
4834 	if (tb[IFA_RT_PRIORITY])
4835 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4836 
4837 	cfg.valid_lft = INFINITY_LIFE_TIME;
4838 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4839 
4840 	if (tb[IFA_CACHEINFO]) {
4841 		struct ifa_cacheinfo *ci;
4842 
4843 		ci = nla_data(tb[IFA_CACHEINFO]);
4844 		cfg.valid_lft = ci->ifa_valid;
4845 		cfg.preferred_lft = ci->ifa_prefered;
4846 	}
4847 
4848 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4849 	if (!dev)
4850 		return -ENODEV;
4851 
4852 	if (tb[IFA_FLAGS])
4853 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4854 	else
4855 		cfg.ifa_flags = ifm->ifa_flags;
4856 
4857 	/* We ignore other flags so far. */
4858 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4859 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4860 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4861 
4862 	idev = ipv6_find_idev(dev);
4863 	if (IS_ERR(idev))
4864 		return PTR_ERR(idev);
4865 
4866 	if (!ipv6_allow_optimistic_dad(net, idev))
4867 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4868 
4869 	if (cfg.ifa_flags & IFA_F_NODAD &&
4870 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4871 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4872 		return -EINVAL;
4873 	}
4874 
4875 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4876 	if (!ifa) {
4877 		/*
4878 		 * It would be best to check for !NLM_F_CREATE here but
4879 		 * userspace already relies on not having to provide this.
4880 		 */
4881 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4882 	}
4883 
4884 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4885 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4886 		err = -EEXIST;
4887 	else
4888 		err = inet6_addr_modify(ifa, &cfg);
4889 
4890 	in6_ifa_put(ifa);
4891 
4892 	return err;
4893 }
4894 
4895 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4896 			  u8 scope, int ifindex)
4897 {
4898 	struct ifaddrmsg *ifm;
4899 
4900 	ifm = nlmsg_data(nlh);
4901 	ifm->ifa_family = AF_INET6;
4902 	ifm->ifa_prefixlen = prefixlen;
4903 	ifm->ifa_flags = flags;
4904 	ifm->ifa_scope = scope;
4905 	ifm->ifa_index = ifindex;
4906 }
4907 
4908 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4909 			 unsigned long tstamp, u32 preferred, u32 valid)
4910 {
4911 	struct ifa_cacheinfo ci;
4912 
4913 	ci.cstamp = cstamp_delta(cstamp);
4914 	ci.tstamp = cstamp_delta(tstamp);
4915 	ci.ifa_prefered = preferred;
4916 	ci.ifa_valid = valid;
4917 
4918 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4919 }
4920 
4921 static inline int rt_scope(int ifa_scope)
4922 {
4923 	if (ifa_scope & IFA_HOST)
4924 		return RT_SCOPE_HOST;
4925 	else if (ifa_scope & IFA_LINK)
4926 		return RT_SCOPE_LINK;
4927 	else if (ifa_scope & IFA_SITE)
4928 		return RT_SCOPE_SITE;
4929 	else
4930 		return RT_SCOPE_UNIVERSE;
4931 }
4932 
4933 static inline int inet6_ifaddr_msgsize(void)
4934 {
4935 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4936 	       + nla_total_size(16) /* IFA_LOCAL */
4937 	       + nla_total_size(16) /* IFA_ADDRESS */
4938 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4939 	       + nla_total_size(4)  /* IFA_FLAGS */
4940 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4941 }
4942 
4943 enum addr_type_t {
4944 	UNICAST_ADDR,
4945 	MULTICAST_ADDR,
4946 	ANYCAST_ADDR,
4947 };
4948 
4949 struct inet6_fill_args {
4950 	u32 portid;
4951 	u32 seq;
4952 	int event;
4953 	unsigned int flags;
4954 	int netnsid;
4955 	int ifindex;
4956 	enum addr_type_t type;
4957 };
4958 
4959 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4960 			     struct inet6_fill_args *args)
4961 {
4962 	struct nlmsghdr  *nlh;
4963 	u32 preferred, valid;
4964 
4965 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4966 			sizeof(struct ifaddrmsg), args->flags);
4967 	if (!nlh)
4968 		return -EMSGSIZE;
4969 
4970 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4971 		      ifa->idev->dev->ifindex);
4972 
4973 	if (args->netnsid >= 0 &&
4974 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4975 		goto error;
4976 
4977 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4978 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4979 		preferred = ifa->prefered_lft;
4980 		valid = ifa->valid_lft;
4981 		if (preferred != INFINITY_LIFE_TIME) {
4982 			long tval = (jiffies - ifa->tstamp)/HZ;
4983 			if (preferred > tval)
4984 				preferred -= tval;
4985 			else
4986 				preferred = 0;
4987 			if (valid != INFINITY_LIFE_TIME) {
4988 				if (valid > tval)
4989 					valid -= tval;
4990 				else
4991 					valid = 0;
4992 			}
4993 		}
4994 	} else {
4995 		preferred = INFINITY_LIFE_TIME;
4996 		valid = INFINITY_LIFE_TIME;
4997 	}
4998 
4999 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5000 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5001 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5002 			goto error;
5003 	} else
5004 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5005 			goto error;
5006 
5007 	if (ifa->rt_priority &&
5008 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
5009 		goto error;
5010 
5011 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5012 		goto error;
5013 
5014 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5015 		goto error;
5016 
5017 	nlmsg_end(skb, nlh);
5018 	return 0;
5019 
5020 error:
5021 	nlmsg_cancel(skb, nlh);
5022 	return -EMSGSIZE;
5023 }
5024 
5025 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5026 			       struct inet6_fill_args *args)
5027 {
5028 	struct nlmsghdr  *nlh;
5029 	u8 scope = RT_SCOPE_UNIVERSE;
5030 	int ifindex = ifmca->idev->dev->ifindex;
5031 
5032 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5033 		scope = RT_SCOPE_SITE;
5034 
5035 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5036 			sizeof(struct ifaddrmsg), args->flags);
5037 	if (!nlh)
5038 		return -EMSGSIZE;
5039 
5040 	if (args->netnsid >= 0 &&
5041 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5042 		return -EMSGSIZE;
5043 
5044 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5045 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5046 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5047 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5048 		nlmsg_cancel(skb, nlh);
5049 		return -EMSGSIZE;
5050 	}
5051 
5052 	nlmsg_end(skb, nlh);
5053 	return 0;
5054 }
5055 
5056 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5057 			       struct inet6_fill_args *args)
5058 {
5059 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5060 	int ifindex = dev ? dev->ifindex : 1;
5061 	struct nlmsghdr  *nlh;
5062 	u8 scope = RT_SCOPE_UNIVERSE;
5063 
5064 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5065 		scope = RT_SCOPE_SITE;
5066 
5067 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5068 			sizeof(struct ifaddrmsg), args->flags);
5069 	if (!nlh)
5070 		return -EMSGSIZE;
5071 
5072 	if (args->netnsid >= 0 &&
5073 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5074 		return -EMSGSIZE;
5075 
5076 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5077 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5078 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5079 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5080 		nlmsg_cancel(skb, nlh);
5081 		return -EMSGSIZE;
5082 	}
5083 
5084 	nlmsg_end(skb, nlh);
5085 	return 0;
5086 }
5087 
5088 /* called with rcu_read_lock() */
5089 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5090 			  struct netlink_callback *cb, int s_ip_idx,
5091 			  struct inet6_fill_args *fillargs)
5092 {
5093 	struct ifmcaddr6 *ifmca;
5094 	struct ifacaddr6 *ifaca;
5095 	int ip_idx = 0;
5096 	int err = 1;
5097 
5098 	read_lock_bh(&idev->lock);
5099 	switch (fillargs->type) {
5100 	case UNICAST_ADDR: {
5101 		struct inet6_ifaddr *ifa;
5102 		fillargs->event = RTM_NEWADDR;
5103 
5104 		/* unicast address incl. temp addr */
5105 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5106 			if (ip_idx < s_ip_idx)
5107 				goto next;
5108 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5109 			if (err < 0)
5110 				break;
5111 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5112 next:
5113 			ip_idx++;
5114 		}
5115 		break;
5116 	}
5117 	case MULTICAST_ADDR:
5118 		fillargs->event = RTM_GETMULTICAST;
5119 
5120 		/* multicast address */
5121 		for (ifmca = idev->mc_list; ifmca;
5122 		     ifmca = ifmca->next, ip_idx++) {
5123 			if (ip_idx < s_ip_idx)
5124 				continue;
5125 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5126 			if (err < 0)
5127 				break;
5128 		}
5129 		break;
5130 	case ANYCAST_ADDR:
5131 		fillargs->event = RTM_GETANYCAST;
5132 		/* anycast address */
5133 		for (ifaca = idev->ac_list; ifaca;
5134 		     ifaca = ifaca->aca_next, ip_idx++) {
5135 			if (ip_idx < s_ip_idx)
5136 				continue;
5137 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5138 			if (err < 0)
5139 				break;
5140 		}
5141 		break;
5142 	default:
5143 		break;
5144 	}
5145 	read_unlock_bh(&idev->lock);
5146 	cb->args[2] = ip_idx;
5147 	return err;
5148 }
5149 
5150 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5151 				       struct inet6_fill_args *fillargs,
5152 				       struct net **tgt_net, struct sock *sk,
5153 				       struct netlink_callback *cb)
5154 {
5155 	struct netlink_ext_ack *extack = cb->extack;
5156 	struct nlattr *tb[IFA_MAX+1];
5157 	struct ifaddrmsg *ifm;
5158 	int err, i;
5159 
5160 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5161 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5162 		return -EINVAL;
5163 	}
5164 
5165 	ifm = nlmsg_data(nlh);
5166 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5167 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5168 		return -EINVAL;
5169 	}
5170 
5171 	fillargs->ifindex = ifm->ifa_index;
5172 	if (fillargs->ifindex) {
5173 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5174 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5175 	}
5176 
5177 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5178 					    ifa_ipv6_policy, extack);
5179 	if (err < 0)
5180 		return err;
5181 
5182 	for (i = 0; i <= IFA_MAX; ++i) {
5183 		if (!tb[i])
5184 			continue;
5185 
5186 		if (i == IFA_TARGET_NETNSID) {
5187 			struct net *net;
5188 
5189 			fillargs->netnsid = nla_get_s32(tb[i]);
5190 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5191 			if (IS_ERR(net)) {
5192 				fillargs->netnsid = -1;
5193 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5194 				return PTR_ERR(net);
5195 			}
5196 			*tgt_net = net;
5197 		} else {
5198 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5199 			return -EINVAL;
5200 		}
5201 	}
5202 
5203 	return 0;
5204 }
5205 
5206 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5207 			   enum addr_type_t type)
5208 {
5209 	const struct nlmsghdr *nlh = cb->nlh;
5210 	struct inet6_fill_args fillargs = {
5211 		.portid = NETLINK_CB(cb->skb).portid,
5212 		.seq = cb->nlh->nlmsg_seq,
5213 		.flags = NLM_F_MULTI,
5214 		.netnsid = -1,
5215 		.type = type,
5216 	};
5217 	struct net *net = sock_net(skb->sk);
5218 	struct net *tgt_net = net;
5219 	int idx, s_idx, s_ip_idx;
5220 	int h, s_h;
5221 	struct net_device *dev;
5222 	struct inet6_dev *idev;
5223 	struct hlist_head *head;
5224 	int err = 0;
5225 
5226 	s_h = cb->args[0];
5227 	s_idx = idx = cb->args[1];
5228 	s_ip_idx = cb->args[2];
5229 
5230 	if (cb->strict_check) {
5231 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5232 						  skb->sk, cb);
5233 		if (err < 0)
5234 			goto put_tgt_net;
5235 
5236 		err = 0;
5237 		if (fillargs.ifindex) {
5238 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5239 			if (!dev) {
5240 				err = -ENODEV;
5241 				goto put_tgt_net;
5242 			}
5243 			idev = __in6_dev_get(dev);
5244 			if (idev) {
5245 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5246 						     &fillargs);
5247 				if (err > 0)
5248 					err = 0;
5249 			}
5250 			goto put_tgt_net;
5251 		}
5252 	}
5253 
5254 	rcu_read_lock();
5255 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5256 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5257 		idx = 0;
5258 		head = &tgt_net->dev_index_head[h];
5259 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5260 			if (idx < s_idx)
5261 				goto cont;
5262 			if (h > s_h || idx > s_idx)
5263 				s_ip_idx = 0;
5264 			idev = __in6_dev_get(dev);
5265 			if (!idev)
5266 				goto cont;
5267 
5268 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5269 					   &fillargs) < 0)
5270 				goto done;
5271 cont:
5272 			idx++;
5273 		}
5274 	}
5275 done:
5276 	rcu_read_unlock();
5277 	cb->args[0] = h;
5278 	cb->args[1] = idx;
5279 put_tgt_net:
5280 	if (fillargs.netnsid >= 0)
5281 		put_net(tgt_net);
5282 
5283 	return skb->len ? : err;
5284 }
5285 
5286 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5287 {
5288 	enum addr_type_t type = UNICAST_ADDR;
5289 
5290 	return inet6_dump_addr(skb, cb, type);
5291 }
5292 
5293 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5294 {
5295 	enum addr_type_t type = MULTICAST_ADDR;
5296 
5297 	return inet6_dump_addr(skb, cb, type);
5298 }
5299 
5300 
5301 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5302 {
5303 	enum addr_type_t type = ANYCAST_ADDR;
5304 
5305 	return inet6_dump_addr(skb, cb, type);
5306 }
5307 
5308 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5309 				       const struct nlmsghdr *nlh,
5310 				       struct nlattr **tb,
5311 				       struct netlink_ext_ack *extack)
5312 {
5313 	struct ifaddrmsg *ifm;
5314 	int i, err;
5315 
5316 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5317 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5318 		return -EINVAL;
5319 	}
5320 
5321 	if (!netlink_strict_get_check(skb))
5322 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5323 					      ifa_ipv6_policy, extack);
5324 
5325 	ifm = nlmsg_data(nlh);
5326 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5327 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5328 		return -EINVAL;
5329 	}
5330 
5331 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5332 					    ifa_ipv6_policy, extack);
5333 	if (err)
5334 		return err;
5335 
5336 	for (i = 0; i <= IFA_MAX; i++) {
5337 		if (!tb[i])
5338 			continue;
5339 
5340 		switch (i) {
5341 		case IFA_TARGET_NETNSID:
5342 		case IFA_ADDRESS:
5343 		case IFA_LOCAL:
5344 			break;
5345 		default:
5346 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5347 			return -EINVAL;
5348 		}
5349 	}
5350 
5351 	return 0;
5352 }
5353 
5354 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5355 			     struct netlink_ext_ack *extack)
5356 {
5357 	struct net *net = sock_net(in_skb->sk);
5358 	struct inet6_fill_args fillargs = {
5359 		.portid = NETLINK_CB(in_skb).portid,
5360 		.seq = nlh->nlmsg_seq,
5361 		.event = RTM_NEWADDR,
5362 		.flags = 0,
5363 		.netnsid = -1,
5364 	};
5365 	struct net *tgt_net = net;
5366 	struct ifaddrmsg *ifm;
5367 	struct nlattr *tb[IFA_MAX+1];
5368 	struct in6_addr *addr = NULL, *peer;
5369 	struct net_device *dev = NULL;
5370 	struct inet6_ifaddr *ifa;
5371 	struct sk_buff *skb;
5372 	int err;
5373 
5374 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5375 	if (err < 0)
5376 		return err;
5377 
5378 	if (tb[IFA_TARGET_NETNSID]) {
5379 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5380 
5381 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5382 						  fillargs.netnsid);
5383 		if (IS_ERR(tgt_net))
5384 			return PTR_ERR(tgt_net);
5385 	}
5386 
5387 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5388 	if (!addr)
5389 		return -EINVAL;
5390 
5391 	ifm = nlmsg_data(nlh);
5392 	if (ifm->ifa_index)
5393 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5394 
5395 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5396 	if (!ifa) {
5397 		err = -EADDRNOTAVAIL;
5398 		goto errout;
5399 	}
5400 
5401 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5402 	if (!skb) {
5403 		err = -ENOBUFS;
5404 		goto errout_ifa;
5405 	}
5406 
5407 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5408 	if (err < 0) {
5409 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5410 		WARN_ON(err == -EMSGSIZE);
5411 		kfree_skb(skb);
5412 		goto errout_ifa;
5413 	}
5414 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5415 errout_ifa:
5416 	in6_ifa_put(ifa);
5417 errout:
5418 	if (dev)
5419 		dev_put(dev);
5420 	if (fillargs.netnsid >= 0)
5421 		put_net(tgt_net);
5422 
5423 	return err;
5424 }
5425 
5426 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5427 {
5428 	struct sk_buff *skb;
5429 	struct net *net = dev_net(ifa->idev->dev);
5430 	struct inet6_fill_args fillargs = {
5431 		.portid = 0,
5432 		.seq = 0,
5433 		.event = event,
5434 		.flags = 0,
5435 		.netnsid = -1,
5436 	};
5437 	int err = -ENOBUFS;
5438 
5439 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5440 	if (!skb)
5441 		goto errout;
5442 
5443 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5444 	if (err < 0) {
5445 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5446 		WARN_ON(err == -EMSGSIZE);
5447 		kfree_skb(skb);
5448 		goto errout;
5449 	}
5450 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5451 	return;
5452 errout:
5453 	if (err < 0)
5454 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5455 }
5456 
5457 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5458 				__s32 *array, int bytes)
5459 {
5460 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5461 
5462 	memset(array, 0, bytes);
5463 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5464 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5465 	array[DEVCONF_MTU6] = cnf->mtu6;
5466 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5467 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5468 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5469 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5470 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5471 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5472 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5473 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5474 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5475 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5476 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5477 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5478 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5479 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5480 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5481 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5482 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5483 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5484 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5485 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5486 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5487 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5488 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5489 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5490 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5491 #ifdef CONFIG_IPV6_ROUTER_PREF
5492 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5493 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5494 		jiffies_to_msecs(cnf->rtr_probe_interval);
5495 #ifdef CONFIG_IPV6_ROUTE_INFO
5496 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5497 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5498 #endif
5499 #endif
5500 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5501 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5502 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5503 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5504 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5505 #endif
5506 #ifdef CONFIG_IPV6_MROUTE
5507 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5508 #endif
5509 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5510 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5511 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5512 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5513 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5514 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5515 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5516 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5517 	/* we omit DEVCONF_STABLE_SECRET for now */
5518 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5519 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5520 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5521 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5522 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5523 #ifdef CONFIG_IPV6_SEG6_HMAC
5524 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5525 #endif
5526 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5527 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5528 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5529 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5530 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5531 }
5532 
5533 static inline size_t inet6_ifla6_size(void)
5534 {
5535 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5536 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5537 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5538 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5539 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5540 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5541 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5542 	     + 0;
5543 }
5544 
5545 static inline size_t inet6_if_nlmsg_size(void)
5546 {
5547 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5548 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5549 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5550 	       + nla_total_size(4) /* IFLA_MTU */
5551 	       + nla_total_size(4) /* IFLA_LINK */
5552 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5553 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5554 }
5555 
5556 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5557 					int bytes)
5558 {
5559 	int i;
5560 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5561 	BUG_ON(pad < 0);
5562 
5563 	/* Use put_unaligned() because stats may not be aligned for u64. */
5564 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5565 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5566 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5567 
5568 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5569 }
5570 
5571 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5572 					int bytes, size_t syncpoff)
5573 {
5574 	int i, c;
5575 	u64 buff[IPSTATS_MIB_MAX];
5576 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5577 
5578 	BUG_ON(pad < 0);
5579 
5580 	memset(buff, 0, sizeof(buff));
5581 	buff[0] = IPSTATS_MIB_MAX;
5582 
5583 	for_each_possible_cpu(c) {
5584 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5585 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5586 	}
5587 
5588 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5589 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5590 }
5591 
5592 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5593 			     int bytes)
5594 {
5595 	switch (attrtype) {
5596 	case IFLA_INET6_STATS:
5597 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5598 				     offsetof(struct ipstats_mib, syncp));
5599 		break;
5600 	case IFLA_INET6_ICMP6STATS:
5601 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5602 		break;
5603 	}
5604 }
5605 
5606 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5607 				  u32 ext_filter_mask)
5608 {
5609 	struct nlattr *nla;
5610 	struct ifla_cacheinfo ci;
5611 
5612 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5613 		goto nla_put_failure;
5614 	ci.max_reasm_len = IPV6_MAXPLEN;
5615 	ci.tstamp = cstamp_delta(idev->tstamp);
5616 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5617 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5618 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5619 		goto nla_put_failure;
5620 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5621 	if (!nla)
5622 		goto nla_put_failure;
5623 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5624 
5625 	/* XXX - MC not implemented */
5626 
5627 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5628 		return 0;
5629 
5630 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5631 	if (!nla)
5632 		goto nla_put_failure;
5633 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5634 
5635 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5636 	if (!nla)
5637 		goto nla_put_failure;
5638 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5639 
5640 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5641 	if (!nla)
5642 		goto nla_put_failure;
5643 	read_lock_bh(&idev->lock);
5644 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5645 	read_unlock_bh(&idev->lock);
5646 
5647 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5648 		goto nla_put_failure;
5649 
5650 	return 0;
5651 
5652 nla_put_failure:
5653 	return -EMSGSIZE;
5654 }
5655 
5656 static size_t inet6_get_link_af_size(const struct net_device *dev,
5657 				     u32 ext_filter_mask)
5658 {
5659 	if (!__in6_dev_get(dev))
5660 		return 0;
5661 
5662 	return inet6_ifla6_size();
5663 }
5664 
5665 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5666 			      u32 ext_filter_mask)
5667 {
5668 	struct inet6_dev *idev = __in6_dev_get(dev);
5669 
5670 	if (!idev)
5671 		return -ENODATA;
5672 
5673 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5674 		return -EMSGSIZE;
5675 
5676 	return 0;
5677 }
5678 
5679 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5680 {
5681 	struct inet6_ifaddr *ifp;
5682 	struct net_device *dev = idev->dev;
5683 	bool clear_token, update_rs = false;
5684 	struct in6_addr ll_addr;
5685 
5686 	ASSERT_RTNL();
5687 
5688 	if (!token)
5689 		return -EINVAL;
5690 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5691 		return -EINVAL;
5692 	if (!ipv6_accept_ra(idev))
5693 		return -EINVAL;
5694 	if (idev->cnf.rtr_solicits == 0)
5695 		return -EINVAL;
5696 
5697 	write_lock_bh(&idev->lock);
5698 
5699 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5700 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5701 
5702 	write_unlock_bh(&idev->lock);
5703 
5704 	clear_token = ipv6_addr_any(token);
5705 	if (clear_token)
5706 		goto update_lft;
5707 
5708 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5709 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5710 			     IFA_F_OPTIMISTIC)) {
5711 		/* If we're not ready, then normal ifup will take care
5712 		 * of this. Otherwise, we need to request our rs here.
5713 		 */
5714 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5715 		update_rs = true;
5716 	}
5717 
5718 update_lft:
5719 	write_lock_bh(&idev->lock);
5720 
5721 	if (update_rs) {
5722 		idev->if_flags |= IF_RS_SENT;
5723 		idev->rs_interval = rfc3315_s14_backoff_init(
5724 			idev->cnf.rtr_solicit_interval);
5725 		idev->rs_probes = 1;
5726 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5727 	}
5728 
5729 	/* Well, that's kinda nasty ... */
5730 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5731 		spin_lock(&ifp->lock);
5732 		if (ifp->tokenized) {
5733 			ifp->valid_lft = 0;
5734 			ifp->prefered_lft = 0;
5735 		}
5736 		spin_unlock(&ifp->lock);
5737 	}
5738 
5739 	write_unlock_bh(&idev->lock);
5740 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5741 	addrconf_verify_rtnl();
5742 	return 0;
5743 }
5744 
5745 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5746 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5747 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5748 };
5749 
5750 static int check_addr_gen_mode(int mode)
5751 {
5752 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5753 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5754 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5755 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5756 		return -EINVAL;
5757 	return 1;
5758 }
5759 
5760 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5761 				int mode)
5762 {
5763 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5764 	    !idev->cnf.stable_secret.initialized &&
5765 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5766 		return -EINVAL;
5767 	return 1;
5768 }
5769 
5770 static int inet6_validate_link_af(const struct net_device *dev,
5771 				  const struct nlattr *nla)
5772 {
5773 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5774 	struct inet6_dev *idev = NULL;
5775 	int err;
5776 
5777 	if (dev) {
5778 		idev = __in6_dev_get(dev);
5779 		if (!idev)
5780 			return -EAFNOSUPPORT;
5781 	}
5782 
5783 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5784 					  inet6_af_policy, NULL);
5785 	if (err)
5786 		return err;
5787 
5788 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5789 		return -EINVAL;
5790 
5791 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5792 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5793 
5794 		if (check_addr_gen_mode(mode) < 0)
5795 			return -EINVAL;
5796 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5797 			return -EINVAL;
5798 	}
5799 
5800 	return 0;
5801 }
5802 
5803 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5804 {
5805 	struct inet6_dev *idev = __in6_dev_get(dev);
5806 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5807 	int err;
5808 
5809 	if (!idev)
5810 		return -EAFNOSUPPORT;
5811 
5812 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5813 		BUG();
5814 
5815 	if (tb[IFLA_INET6_TOKEN]) {
5816 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5817 		if (err)
5818 			return err;
5819 	}
5820 
5821 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5822 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5823 
5824 		idev->cnf.addr_gen_mode = mode;
5825 	}
5826 
5827 	return 0;
5828 }
5829 
5830 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5831 			     u32 portid, u32 seq, int event, unsigned int flags)
5832 {
5833 	struct net_device *dev = idev->dev;
5834 	struct ifinfomsg *hdr;
5835 	struct nlmsghdr *nlh;
5836 	void *protoinfo;
5837 
5838 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5839 	if (!nlh)
5840 		return -EMSGSIZE;
5841 
5842 	hdr = nlmsg_data(nlh);
5843 	hdr->ifi_family = AF_INET6;
5844 	hdr->__ifi_pad = 0;
5845 	hdr->ifi_type = dev->type;
5846 	hdr->ifi_index = dev->ifindex;
5847 	hdr->ifi_flags = dev_get_flags(dev);
5848 	hdr->ifi_change = 0;
5849 
5850 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5851 	    (dev->addr_len &&
5852 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5853 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5854 	    (dev->ifindex != dev_get_iflink(dev) &&
5855 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5856 	    nla_put_u8(skb, IFLA_OPERSTATE,
5857 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5858 		goto nla_put_failure;
5859 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5860 	if (!protoinfo)
5861 		goto nla_put_failure;
5862 
5863 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5864 		goto nla_put_failure;
5865 
5866 	nla_nest_end(skb, protoinfo);
5867 	nlmsg_end(skb, nlh);
5868 	return 0;
5869 
5870 nla_put_failure:
5871 	nlmsg_cancel(skb, nlh);
5872 	return -EMSGSIZE;
5873 }
5874 
5875 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5876 				   struct netlink_ext_ack *extack)
5877 {
5878 	struct ifinfomsg *ifm;
5879 
5880 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5881 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5882 		return -EINVAL;
5883 	}
5884 
5885 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5886 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5887 		return -EINVAL;
5888 	}
5889 
5890 	ifm = nlmsg_data(nlh);
5891 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5892 	    ifm->ifi_change || ifm->ifi_index) {
5893 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5894 		return -EINVAL;
5895 	}
5896 
5897 	return 0;
5898 }
5899 
5900 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5901 {
5902 	struct net *net = sock_net(skb->sk);
5903 	int h, s_h;
5904 	int idx = 0, s_idx;
5905 	struct net_device *dev;
5906 	struct inet6_dev *idev;
5907 	struct hlist_head *head;
5908 
5909 	/* only requests using strict checking can pass data to
5910 	 * influence the dump
5911 	 */
5912 	if (cb->strict_check) {
5913 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5914 
5915 		if (err < 0)
5916 			return err;
5917 	}
5918 
5919 	s_h = cb->args[0];
5920 	s_idx = cb->args[1];
5921 
5922 	rcu_read_lock();
5923 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5924 		idx = 0;
5925 		head = &net->dev_index_head[h];
5926 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5927 			if (idx < s_idx)
5928 				goto cont;
5929 			idev = __in6_dev_get(dev);
5930 			if (!idev)
5931 				goto cont;
5932 			if (inet6_fill_ifinfo(skb, idev,
5933 					      NETLINK_CB(cb->skb).portid,
5934 					      cb->nlh->nlmsg_seq,
5935 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5936 				goto out;
5937 cont:
5938 			idx++;
5939 		}
5940 	}
5941 out:
5942 	rcu_read_unlock();
5943 	cb->args[1] = idx;
5944 	cb->args[0] = h;
5945 
5946 	return skb->len;
5947 }
5948 
5949 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5950 {
5951 	struct sk_buff *skb;
5952 	struct net *net = dev_net(idev->dev);
5953 	int err = -ENOBUFS;
5954 
5955 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5956 	if (!skb)
5957 		goto errout;
5958 
5959 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5960 	if (err < 0) {
5961 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5962 		WARN_ON(err == -EMSGSIZE);
5963 		kfree_skb(skb);
5964 		goto errout;
5965 	}
5966 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5967 	return;
5968 errout:
5969 	if (err < 0)
5970 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5971 }
5972 
5973 static inline size_t inet6_prefix_nlmsg_size(void)
5974 {
5975 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5976 	       + nla_total_size(sizeof(struct in6_addr))
5977 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5978 }
5979 
5980 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5981 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5982 			     int event, unsigned int flags)
5983 {
5984 	struct prefixmsg *pmsg;
5985 	struct nlmsghdr *nlh;
5986 	struct prefix_cacheinfo	ci;
5987 
5988 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5989 	if (!nlh)
5990 		return -EMSGSIZE;
5991 
5992 	pmsg = nlmsg_data(nlh);
5993 	pmsg->prefix_family = AF_INET6;
5994 	pmsg->prefix_pad1 = 0;
5995 	pmsg->prefix_pad2 = 0;
5996 	pmsg->prefix_ifindex = idev->dev->ifindex;
5997 	pmsg->prefix_len = pinfo->prefix_len;
5998 	pmsg->prefix_type = pinfo->type;
5999 	pmsg->prefix_pad3 = 0;
6000 	pmsg->prefix_flags = 0;
6001 	if (pinfo->onlink)
6002 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
6003 	if (pinfo->autoconf)
6004 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
6005 
6006 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6007 		goto nla_put_failure;
6008 	ci.preferred_time = ntohl(pinfo->prefered);
6009 	ci.valid_time = ntohl(pinfo->valid);
6010 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6011 		goto nla_put_failure;
6012 	nlmsg_end(skb, nlh);
6013 	return 0;
6014 
6015 nla_put_failure:
6016 	nlmsg_cancel(skb, nlh);
6017 	return -EMSGSIZE;
6018 }
6019 
6020 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6021 			 struct prefix_info *pinfo)
6022 {
6023 	struct sk_buff *skb;
6024 	struct net *net = dev_net(idev->dev);
6025 	int err = -ENOBUFS;
6026 
6027 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6028 	if (!skb)
6029 		goto errout;
6030 
6031 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6032 	if (err < 0) {
6033 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6034 		WARN_ON(err == -EMSGSIZE);
6035 		kfree_skb(skb);
6036 		goto errout;
6037 	}
6038 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6039 	return;
6040 errout:
6041 	if (err < 0)
6042 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6043 }
6044 
6045 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6046 {
6047 	struct net *net = dev_net(ifp->idev->dev);
6048 
6049 	if (event)
6050 		ASSERT_RTNL();
6051 
6052 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6053 
6054 	switch (event) {
6055 	case RTM_NEWADDR:
6056 		/*
6057 		 * If the address was optimistic we inserted the route at the
6058 		 * start of our DAD process, so we don't need to do it again.
6059 		 * If the device was taken down in the middle of the DAD
6060 		 * cycle there is a race where we could get here without a
6061 		 * host route, so nothing to insert. That will be fixed when
6062 		 * the device is brought up.
6063 		 */
6064 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6065 			ip6_ins_rt(net, ifp->rt);
6066 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6067 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6068 				&ifp->addr, ifp->idev->dev->name);
6069 		}
6070 
6071 		if (ifp->idev->cnf.forwarding)
6072 			addrconf_join_anycast(ifp);
6073 		if (!ipv6_addr_any(&ifp->peer_addr))
6074 			addrconf_prefix_route(&ifp->peer_addr, 128,
6075 					      ifp->rt_priority, ifp->idev->dev,
6076 					      0, 0, GFP_ATOMIC);
6077 		break;
6078 	case RTM_DELADDR:
6079 		if (ifp->idev->cnf.forwarding)
6080 			addrconf_leave_anycast(ifp);
6081 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6082 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6083 			struct fib6_info *rt;
6084 
6085 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6086 						       ifp->idev->dev, 0, 0,
6087 						       false);
6088 			if (rt)
6089 				ip6_del_rt(net, rt);
6090 		}
6091 		if (ifp->rt) {
6092 			ip6_del_rt(net, ifp->rt);
6093 			ifp->rt = NULL;
6094 		}
6095 		rt_genid_bump_ipv6(net);
6096 		break;
6097 	}
6098 	atomic_inc(&net->ipv6.dev_addr_genid);
6099 }
6100 
6101 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6102 {
6103 	rcu_read_lock_bh();
6104 	if (likely(ifp->idev->dead == 0))
6105 		__ipv6_ifa_notify(event, ifp);
6106 	rcu_read_unlock_bh();
6107 }
6108 
6109 #ifdef CONFIG_SYSCTL
6110 
6111 static
6112 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6113 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6114 {
6115 	int *valp = ctl->data;
6116 	int val = *valp;
6117 	loff_t pos = *ppos;
6118 	struct ctl_table lctl;
6119 	int ret;
6120 
6121 	/*
6122 	 * ctl->data points to idev->cnf.forwarding, we should
6123 	 * not modify it until we get the rtnl lock.
6124 	 */
6125 	lctl = *ctl;
6126 	lctl.data = &val;
6127 
6128 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6129 
6130 	if (write)
6131 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6132 	if (ret)
6133 		*ppos = pos;
6134 	return ret;
6135 }
6136 
6137 static
6138 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6139 			void __user *buffer, size_t *lenp, loff_t *ppos)
6140 {
6141 	struct inet6_dev *idev = ctl->extra1;
6142 	int min_mtu = IPV6_MIN_MTU;
6143 	struct ctl_table lctl;
6144 
6145 	lctl = *ctl;
6146 	lctl.extra1 = &min_mtu;
6147 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6148 
6149 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6150 }
6151 
6152 static void dev_disable_change(struct inet6_dev *idev)
6153 {
6154 	struct netdev_notifier_info info;
6155 
6156 	if (!idev || !idev->dev)
6157 		return;
6158 
6159 	netdev_notifier_info_init(&info, idev->dev);
6160 	if (idev->cnf.disable_ipv6)
6161 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6162 	else
6163 		addrconf_notify(NULL, NETDEV_UP, &info);
6164 }
6165 
6166 static void addrconf_disable_change(struct net *net, __s32 newf)
6167 {
6168 	struct net_device *dev;
6169 	struct inet6_dev *idev;
6170 
6171 	for_each_netdev(net, dev) {
6172 		idev = __in6_dev_get(dev);
6173 		if (idev) {
6174 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6175 			idev->cnf.disable_ipv6 = newf;
6176 			if (changed)
6177 				dev_disable_change(idev);
6178 		}
6179 	}
6180 }
6181 
6182 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6183 {
6184 	struct net *net;
6185 	int old;
6186 
6187 	if (!rtnl_trylock())
6188 		return restart_syscall();
6189 
6190 	net = (struct net *)table->extra2;
6191 	old = *p;
6192 	*p = newf;
6193 
6194 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6195 		rtnl_unlock();
6196 		return 0;
6197 	}
6198 
6199 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6200 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6201 		addrconf_disable_change(net, newf);
6202 	} else if ((!newf) ^ (!old))
6203 		dev_disable_change((struct inet6_dev *)table->extra1);
6204 
6205 	rtnl_unlock();
6206 	return 0;
6207 }
6208 
6209 static
6210 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6211 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6212 {
6213 	int *valp = ctl->data;
6214 	int val = *valp;
6215 	loff_t pos = *ppos;
6216 	struct ctl_table lctl;
6217 	int ret;
6218 
6219 	/*
6220 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6221 	 * not modify it until we get the rtnl lock.
6222 	 */
6223 	lctl = *ctl;
6224 	lctl.data = &val;
6225 
6226 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6227 
6228 	if (write)
6229 		ret = addrconf_disable_ipv6(ctl, valp, val);
6230 	if (ret)
6231 		*ppos = pos;
6232 	return ret;
6233 }
6234 
6235 static
6236 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6237 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6238 {
6239 	int *valp = ctl->data;
6240 	int ret;
6241 	int old, new;
6242 
6243 	old = *valp;
6244 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6245 	new = *valp;
6246 
6247 	if (write && old != new) {
6248 		struct net *net = ctl->extra2;
6249 
6250 		if (!rtnl_trylock())
6251 			return restart_syscall();
6252 
6253 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6254 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6255 						     NETCONFA_PROXY_NEIGH,
6256 						     NETCONFA_IFINDEX_DEFAULT,
6257 						     net->ipv6.devconf_dflt);
6258 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6259 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6260 						     NETCONFA_PROXY_NEIGH,
6261 						     NETCONFA_IFINDEX_ALL,
6262 						     net->ipv6.devconf_all);
6263 		else {
6264 			struct inet6_dev *idev = ctl->extra1;
6265 
6266 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6267 						     NETCONFA_PROXY_NEIGH,
6268 						     idev->dev->ifindex,
6269 						     &idev->cnf);
6270 		}
6271 		rtnl_unlock();
6272 	}
6273 
6274 	return ret;
6275 }
6276 
6277 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6278 					 void __user *buffer, size_t *lenp,
6279 					 loff_t *ppos)
6280 {
6281 	int ret = 0;
6282 	u32 new_val;
6283 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6284 	struct net *net = (struct net *)ctl->extra2;
6285 	struct ctl_table tmp = {
6286 		.data = &new_val,
6287 		.maxlen = sizeof(new_val),
6288 		.mode = ctl->mode,
6289 	};
6290 
6291 	if (!rtnl_trylock())
6292 		return restart_syscall();
6293 
6294 	new_val = *((u32 *)ctl->data);
6295 
6296 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6297 	if (ret != 0)
6298 		goto out;
6299 
6300 	if (write) {
6301 		if (check_addr_gen_mode(new_val) < 0) {
6302 			ret = -EINVAL;
6303 			goto out;
6304 		}
6305 
6306 		if (idev) {
6307 			if (check_stable_privacy(idev, net, new_val) < 0) {
6308 				ret = -EINVAL;
6309 				goto out;
6310 			}
6311 
6312 			if (idev->cnf.addr_gen_mode != new_val) {
6313 				idev->cnf.addr_gen_mode = new_val;
6314 				addrconf_dev_config(idev->dev);
6315 			}
6316 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6317 			struct net_device *dev;
6318 
6319 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6320 			for_each_netdev(net, dev) {
6321 				idev = __in6_dev_get(dev);
6322 				if (idev &&
6323 				    idev->cnf.addr_gen_mode != new_val) {
6324 					idev->cnf.addr_gen_mode = new_val;
6325 					addrconf_dev_config(idev->dev);
6326 				}
6327 			}
6328 		}
6329 
6330 		*((u32 *)ctl->data) = new_val;
6331 	}
6332 
6333 out:
6334 	rtnl_unlock();
6335 
6336 	return ret;
6337 }
6338 
6339 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6340 					 void __user *buffer, size_t *lenp,
6341 					 loff_t *ppos)
6342 {
6343 	int err;
6344 	struct in6_addr addr;
6345 	char str[IPV6_MAX_STRLEN];
6346 	struct ctl_table lctl = *ctl;
6347 	struct net *net = ctl->extra2;
6348 	struct ipv6_stable_secret *secret = ctl->data;
6349 
6350 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6351 		return -EIO;
6352 
6353 	lctl.maxlen = IPV6_MAX_STRLEN;
6354 	lctl.data = str;
6355 
6356 	if (!rtnl_trylock())
6357 		return restart_syscall();
6358 
6359 	if (!write && !secret->initialized) {
6360 		err = -EIO;
6361 		goto out;
6362 	}
6363 
6364 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6365 	if (err >= sizeof(str)) {
6366 		err = -EIO;
6367 		goto out;
6368 	}
6369 
6370 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6371 	if (err || !write)
6372 		goto out;
6373 
6374 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6375 		err = -EIO;
6376 		goto out;
6377 	}
6378 
6379 	secret->initialized = true;
6380 	secret->secret = addr;
6381 
6382 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6383 		struct net_device *dev;
6384 
6385 		for_each_netdev(net, dev) {
6386 			struct inet6_dev *idev = __in6_dev_get(dev);
6387 
6388 			if (idev) {
6389 				idev->cnf.addr_gen_mode =
6390 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6391 			}
6392 		}
6393 	} else {
6394 		struct inet6_dev *idev = ctl->extra1;
6395 
6396 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6397 	}
6398 
6399 out:
6400 	rtnl_unlock();
6401 
6402 	return err;
6403 }
6404 
6405 static
6406 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6407 						int write,
6408 						void __user *buffer,
6409 						size_t *lenp,
6410 						loff_t *ppos)
6411 {
6412 	int *valp = ctl->data;
6413 	int val = *valp;
6414 	loff_t pos = *ppos;
6415 	struct ctl_table lctl;
6416 	int ret;
6417 
6418 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6419 	 * we should not modify it until we get the rtnl lock.
6420 	 */
6421 	lctl = *ctl;
6422 	lctl.data = &val;
6423 
6424 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6425 
6426 	if (write)
6427 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6428 	if (ret)
6429 		*ppos = pos;
6430 	return ret;
6431 }
6432 
6433 static
6434 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6435 {
6436 	if (rt) {
6437 		if (action)
6438 			rt->dst.flags |= DST_NOPOLICY;
6439 		else
6440 			rt->dst.flags &= ~DST_NOPOLICY;
6441 	}
6442 }
6443 
6444 static
6445 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6446 {
6447 	struct inet6_ifaddr *ifa;
6448 
6449 	read_lock_bh(&idev->lock);
6450 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6451 		spin_lock(&ifa->lock);
6452 		if (ifa->rt) {
6453 			/* host routes only use builtin fib6_nh */
6454 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6455 			int cpu;
6456 
6457 			rcu_read_lock();
6458 			ifa->rt->dst_nopolicy = val ? true : false;
6459 			if (nh->rt6i_pcpu) {
6460 				for_each_possible_cpu(cpu) {
6461 					struct rt6_info **rtp;
6462 
6463 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6464 					addrconf_set_nopolicy(*rtp, val);
6465 				}
6466 			}
6467 			rcu_read_unlock();
6468 		}
6469 		spin_unlock(&ifa->lock);
6470 	}
6471 	read_unlock_bh(&idev->lock);
6472 }
6473 
6474 static
6475 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6476 {
6477 	struct inet6_dev *idev;
6478 	struct net *net;
6479 
6480 	if (!rtnl_trylock())
6481 		return restart_syscall();
6482 
6483 	*valp = val;
6484 
6485 	net = (struct net *)ctl->extra2;
6486 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6487 		rtnl_unlock();
6488 		return 0;
6489 	}
6490 
6491 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6492 		struct net_device *dev;
6493 
6494 		for_each_netdev(net, dev) {
6495 			idev = __in6_dev_get(dev);
6496 			if (idev)
6497 				addrconf_disable_policy_idev(idev, val);
6498 		}
6499 	} else {
6500 		idev = (struct inet6_dev *)ctl->extra1;
6501 		addrconf_disable_policy_idev(idev, val);
6502 	}
6503 
6504 	rtnl_unlock();
6505 	return 0;
6506 }
6507 
6508 static
6509 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6510 				   void __user *buffer, size_t *lenp,
6511 				   loff_t *ppos)
6512 {
6513 	int *valp = ctl->data;
6514 	int val = *valp;
6515 	loff_t pos = *ppos;
6516 	struct ctl_table lctl;
6517 	int ret;
6518 
6519 	lctl = *ctl;
6520 	lctl.data = &val;
6521 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6522 
6523 	if (write && (*valp != val))
6524 		ret = addrconf_disable_policy(ctl, valp, val);
6525 
6526 	if (ret)
6527 		*ppos = pos;
6528 
6529 	return ret;
6530 }
6531 
6532 static int minus_one = -1;
6533 static const int two_five_five = 255;
6534 
6535 static const struct ctl_table addrconf_sysctl[] = {
6536 	{
6537 		.procname	= "forwarding",
6538 		.data		= &ipv6_devconf.forwarding,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= addrconf_sysctl_forward,
6542 	},
6543 	{
6544 		.procname	= "hop_limit",
6545 		.data		= &ipv6_devconf.hop_limit,
6546 		.maxlen		= sizeof(int),
6547 		.mode		= 0644,
6548 		.proc_handler	= proc_dointvec_minmax,
6549 		.extra1		= (void *)SYSCTL_ONE,
6550 		.extra2		= (void *)&two_five_five,
6551 	},
6552 	{
6553 		.procname	= "mtu",
6554 		.data		= &ipv6_devconf.mtu6,
6555 		.maxlen		= sizeof(int),
6556 		.mode		= 0644,
6557 		.proc_handler	= addrconf_sysctl_mtu,
6558 	},
6559 	{
6560 		.procname	= "accept_ra",
6561 		.data		= &ipv6_devconf.accept_ra,
6562 		.maxlen		= sizeof(int),
6563 		.mode		= 0644,
6564 		.proc_handler	= proc_dointvec,
6565 	},
6566 	{
6567 		.procname	= "accept_redirects",
6568 		.data		= &ipv6_devconf.accept_redirects,
6569 		.maxlen		= sizeof(int),
6570 		.mode		= 0644,
6571 		.proc_handler	= proc_dointvec,
6572 	},
6573 	{
6574 		.procname	= "autoconf",
6575 		.data		= &ipv6_devconf.autoconf,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec,
6579 	},
6580 	{
6581 		.procname	= "dad_transmits",
6582 		.data		= &ipv6_devconf.dad_transmits,
6583 		.maxlen		= sizeof(int),
6584 		.mode		= 0644,
6585 		.proc_handler	= proc_dointvec,
6586 	},
6587 	{
6588 		.procname	= "router_solicitations",
6589 		.data		= &ipv6_devconf.rtr_solicits,
6590 		.maxlen		= sizeof(int),
6591 		.mode		= 0644,
6592 		.proc_handler	= proc_dointvec_minmax,
6593 		.extra1		= &minus_one,
6594 	},
6595 	{
6596 		.procname	= "router_solicitation_interval",
6597 		.data		= &ipv6_devconf.rtr_solicit_interval,
6598 		.maxlen		= sizeof(int),
6599 		.mode		= 0644,
6600 		.proc_handler	= proc_dointvec_jiffies,
6601 	},
6602 	{
6603 		.procname	= "router_solicitation_max_interval",
6604 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6605 		.maxlen		= sizeof(int),
6606 		.mode		= 0644,
6607 		.proc_handler	= proc_dointvec_jiffies,
6608 	},
6609 	{
6610 		.procname	= "router_solicitation_delay",
6611 		.data		= &ipv6_devconf.rtr_solicit_delay,
6612 		.maxlen		= sizeof(int),
6613 		.mode		= 0644,
6614 		.proc_handler	= proc_dointvec_jiffies,
6615 	},
6616 	{
6617 		.procname	= "force_mld_version",
6618 		.data		= &ipv6_devconf.force_mld_version,
6619 		.maxlen		= sizeof(int),
6620 		.mode		= 0644,
6621 		.proc_handler	= proc_dointvec,
6622 	},
6623 	{
6624 		.procname	= "mldv1_unsolicited_report_interval",
6625 		.data		=
6626 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6627 		.maxlen		= sizeof(int),
6628 		.mode		= 0644,
6629 		.proc_handler	= proc_dointvec_ms_jiffies,
6630 	},
6631 	{
6632 		.procname	= "mldv2_unsolicited_report_interval",
6633 		.data		=
6634 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6635 		.maxlen		= sizeof(int),
6636 		.mode		= 0644,
6637 		.proc_handler	= proc_dointvec_ms_jiffies,
6638 	},
6639 	{
6640 		.procname	= "use_tempaddr",
6641 		.data		= &ipv6_devconf.use_tempaddr,
6642 		.maxlen		= sizeof(int),
6643 		.mode		= 0644,
6644 		.proc_handler	= proc_dointvec,
6645 	},
6646 	{
6647 		.procname	= "temp_valid_lft",
6648 		.data		= &ipv6_devconf.temp_valid_lft,
6649 		.maxlen		= sizeof(int),
6650 		.mode		= 0644,
6651 		.proc_handler	= proc_dointvec,
6652 	},
6653 	{
6654 		.procname	= "temp_prefered_lft",
6655 		.data		= &ipv6_devconf.temp_prefered_lft,
6656 		.maxlen		= sizeof(int),
6657 		.mode		= 0644,
6658 		.proc_handler	= proc_dointvec,
6659 	},
6660 	{
6661 		.procname	= "regen_max_retry",
6662 		.data		= &ipv6_devconf.regen_max_retry,
6663 		.maxlen		= sizeof(int),
6664 		.mode		= 0644,
6665 		.proc_handler	= proc_dointvec,
6666 	},
6667 	{
6668 		.procname	= "max_desync_factor",
6669 		.data		= &ipv6_devconf.max_desync_factor,
6670 		.maxlen		= sizeof(int),
6671 		.mode		= 0644,
6672 		.proc_handler	= proc_dointvec,
6673 	},
6674 	{
6675 		.procname	= "max_addresses",
6676 		.data		= &ipv6_devconf.max_addresses,
6677 		.maxlen		= sizeof(int),
6678 		.mode		= 0644,
6679 		.proc_handler	= proc_dointvec,
6680 	},
6681 	{
6682 		.procname	= "accept_ra_defrtr",
6683 		.data		= &ipv6_devconf.accept_ra_defrtr,
6684 		.maxlen		= sizeof(int),
6685 		.mode		= 0644,
6686 		.proc_handler	= proc_dointvec,
6687 	},
6688 	{
6689 		.procname	= "accept_ra_min_hop_limit",
6690 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6691 		.maxlen		= sizeof(int),
6692 		.mode		= 0644,
6693 		.proc_handler	= proc_dointvec,
6694 	},
6695 	{
6696 		.procname	= "accept_ra_pinfo",
6697 		.data		= &ipv6_devconf.accept_ra_pinfo,
6698 		.maxlen		= sizeof(int),
6699 		.mode		= 0644,
6700 		.proc_handler	= proc_dointvec,
6701 	},
6702 #ifdef CONFIG_IPV6_ROUTER_PREF
6703 	{
6704 		.procname	= "accept_ra_rtr_pref",
6705 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6706 		.maxlen		= sizeof(int),
6707 		.mode		= 0644,
6708 		.proc_handler	= proc_dointvec,
6709 	},
6710 	{
6711 		.procname	= "router_probe_interval",
6712 		.data		= &ipv6_devconf.rtr_probe_interval,
6713 		.maxlen		= sizeof(int),
6714 		.mode		= 0644,
6715 		.proc_handler	= proc_dointvec_jiffies,
6716 	},
6717 #ifdef CONFIG_IPV6_ROUTE_INFO
6718 	{
6719 		.procname	= "accept_ra_rt_info_min_plen",
6720 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6721 		.maxlen		= sizeof(int),
6722 		.mode		= 0644,
6723 		.proc_handler	= proc_dointvec,
6724 	},
6725 	{
6726 		.procname	= "accept_ra_rt_info_max_plen",
6727 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6728 		.maxlen		= sizeof(int),
6729 		.mode		= 0644,
6730 		.proc_handler	= proc_dointvec,
6731 	},
6732 #endif
6733 #endif
6734 	{
6735 		.procname	= "proxy_ndp",
6736 		.data		= &ipv6_devconf.proxy_ndp,
6737 		.maxlen		= sizeof(int),
6738 		.mode		= 0644,
6739 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6740 	},
6741 	{
6742 		.procname	= "accept_source_route",
6743 		.data		= &ipv6_devconf.accept_source_route,
6744 		.maxlen		= sizeof(int),
6745 		.mode		= 0644,
6746 		.proc_handler	= proc_dointvec,
6747 	},
6748 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6749 	{
6750 		.procname	= "optimistic_dad",
6751 		.data		= &ipv6_devconf.optimistic_dad,
6752 		.maxlen		= sizeof(int),
6753 		.mode		= 0644,
6754 		.proc_handler   = proc_dointvec,
6755 	},
6756 	{
6757 		.procname	= "use_optimistic",
6758 		.data		= &ipv6_devconf.use_optimistic,
6759 		.maxlen		= sizeof(int),
6760 		.mode		= 0644,
6761 		.proc_handler	= proc_dointvec,
6762 	},
6763 #endif
6764 #ifdef CONFIG_IPV6_MROUTE
6765 	{
6766 		.procname	= "mc_forwarding",
6767 		.data		= &ipv6_devconf.mc_forwarding,
6768 		.maxlen		= sizeof(int),
6769 		.mode		= 0444,
6770 		.proc_handler	= proc_dointvec,
6771 	},
6772 #endif
6773 	{
6774 		.procname	= "disable_ipv6",
6775 		.data		= &ipv6_devconf.disable_ipv6,
6776 		.maxlen		= sizeof(int),
6777 		.mode		= 0644,
6778 		.proc_handler	= addrconf_sysctl_disable,
6779 	},
6780 	{
6781 		.procname	= "accept_dad",
6782 		.data		= &ipv6_devconf.accept_dad,
6783 		.maxlen		= sizeof(int),
6784 		.mode		= 0644,
6785 		.proc_handler	= proc_dointvec,
6786 	},
6787 	{
6788 		.procname	= "force_tllao",
6789 		.data		= &ipv6_devconf.force_tllao,
6790 		.maxlen		= sizeof(int),
6791 		.mode		= 0644,
6792 		.proc_handler	= proc_dointvec
6793 	},
6794 	{
6795 		.procname	= "ndisc_notify",
6796 		.data		= &ipv6_devconf.ndisc_notify,
6797 		.maxlen		= sizeof(int),
6798 		.mode		= 0644,
6799 		.proc_handler	= proc_dointvec
6800 	},
6801 	{
6802 		.procname	= "suppress_frag_ndisc",
6803 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6804 		.maxlen		= sizeof(int),
6805 		.mode		= 0644,
6806 		.proc_handler	= proc_dointvec
6807 	},
6808 	{
6809 		.procname	= "accept_ra_from_local",
6810 		.data		= &ipv6_devconf.accept_ra_from_local,
6811 		.maxlen		= sizeof(int),
6812 		.mode		= 0644,
6813 		.proc_handler	= proc_dointvec,
6814 	},
6815 	{
6816 		.procname	= "accept_ra_mtu",
6817 		.data		= &ipv6_devconf.accept_ra_mtu,
6818 		.maxlen		= sizeof(int),
6819 		.mode		= 0644,
6820 		.proc_handler	= proc_dointvec,
6821 	},
6822 	{
6823 		.procname	= "stable_secret",
6824 		.data		= &ipv6_devconf.stable_secret,
6825 		.maxlen		= IPV6_MAX_STRLEN,
6826 		.mode		= 0600,
6827 		.proc_handler	= addrconf_sysctl_stable_secret,
6828 	},
6829 	{
6830 		.procname	= "use_oif_addrs_only",
6831 		.data		= &ipv6_devconf.use_oif_addrs_only,
6832 		.maxlen		= sizeof(int),
6833 		.mode		= 0644,
6834 		.proc_handler	= proc_dointvec,
6835 	},
6836 	{
6837 		.procname	= "ignore_routes_with_linkdown",
6838 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6839 		.maxlen		= sizeof(int),
6840 		.mode		= 0644,
6841 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6842 	},
6843 	{
6844 		.procname	= "drop_unicast_in_l2_multicast",
6845 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6846 		.maxlen		= sizeof(int),
6847 		.mode		= 0644,
6848 		.proc_handler	= proc_dointvec,
6849 	},
6850 	{
6851 		.procname	= "drop_unsolicited_na",
6852 		.data		= &ipv6_devconf.drop_unsolicited_na,
6853 		.maxlen		= sizeof(int),
6854 		.mode		= 0644,
6855 		.proc_handler	= proc_dointvec,
6856 	},
6857 	{
6858 		.procname	= "keep_addr_on_down",
6859 		.data		= &ipv6_devconf.keep_addr_on_down,
6860 		.maxlen		= sizeof(int),
6861 		.mode		= 0644,
6862 		.proc_handler	= proc_dointvec,
6863 
6864 	},
6865 	{
6866 		.procname	= "seg6_enabled",
6867 		.data		= &ipv6_devconf.seg6_enabled,
6868 		.maxlen		= sizeof(int),
6869 		.mode		= 0644,
6870 		.proc_handler	= proc_dointvec,
6871 	},
6872 #ifdef CONFIG_IPV6_SEG6_HMAC
6873 	{
6874 		.procname	= "seg6_require_hmac",
6875 		.data		= &ipv6_devconf.seg6_require_hmac,
6876 		.maxlen		= sizeof(int),
6877 		.mode		= 0644,
6878 		.proc_handler	= proc_dointvec,
6879 	},
6880 #endif
6881 	{
6882 		.procname       = "enhanced_dad",
6883 		.data           = &ipv6_devconf.enhanced_dad,
6884 		.maxlen         = sizeof(int),
6885 		.mode           = 0644,
6886 		.proc_handler   = proc_dointvec,
6887 	},
6888 	{
6889 		.procname		= "addr_gen_mode",
6890 		.data			= &ipv6_devconf.addr_gen_mode,
6891 		.maxlen			= sizeof(int),
6892 		.mode			= 0644,
6893 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6894 	},
6895 	{
6896 		.procname       = "disable_policy",
6897 		.data           = &ipv6_devconf.disable_policy,
6898 		.maxlen         = sizeof(int),
6899 		.mode           = 0644,
6900 		.proc_handler   = addrconf_sysctl_disable_policy,
6901 	},
6902 	{
6903 		.procname	= "ndisc_tclass",
6904 		.data		= &ipv6_devconf.ndisc_tclass,
6905 		.maxlen		= sizeof(int),
6906 		.mode		= 0644,
6907 		.proc_handler	= proc_dointvec_minmax,
6908 		.extra1		= (void *)SYSCTL_ZERO,
6909 		.extra2		= (void *)&two_five_five,
6910 	},
6911 	{
6912 		.procname	= "rpl_seg_enabled",
6913 		.data		= &ipv6_devconf.rpl_seg_enabled,
6914 		.maxlen		= sizeof(int),
6915 		.mode		= 0644,
6916 		.proc_handler	= proc_dointvec,
6917 	},
6918 	{
6919 		/* sentinel */
6920 	}
6921 };
6922 
6923 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6924 		struct inet6_dev *idev, struct ipv6_devconf *p)
6925 {
6926 	int i, ifindex;
6927 	struct ctl_table *table;
6928 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6929 
6930 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6931 	if (!table)
6932 		goto out;
6933 
6934 	for (i = 0; table[i].data; i++) {
6935 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6936 		/* If one of these is already set, then it is not safe to
6937 		 * overwrite either of them: this makes proc_dointvec_minmax
6938 		 * usable.
6939 		 */
6940 		if (!table[i].extra1 && !table[i].extra2) {
6941 			table[i].extra1 = idev; /* embedded; no ref */
6942 			table[i].extra2 = net;
6943 		}
6944 	}
6945 
6946 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6947 
6948 	p->sysctl_header = register_net_sysctl(net, path, table);
6949 	if (!p->sysctl_header)
6950 		goto free;
6951 
6952 	if (!strcmp(dev_name, "all"))
6953 		ifindex = NETCONFA_IFINDEX_ALL;
6954 	else if (!strcmp(dev_name, "default"))
6955 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6956 	else
6957 		ifindex = idev->dev->ifindex;
6958 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6959 				     ifindex, p);
6960 	return 0;
6961 
6962 free:
6963 	kfree(table);
6964 out:
6965 	return -ENOBUFS;
6966 }
6967 
6968 static void __addrconf_sysctl_unregister(struct net *net,
6969 					 struct ipv6_devconf *p, int ifindex)
6970 {
6971 	struct ctl_table *table;
6972 
6973 	if (!p->sysctl_header)
6974 		return;
6975 
6976 	table = p->sysctl_header->ctl_table_arg;
6977 	unregister_net_sysctl_table(p->sysctl_header);
6978 	p->sysctl_header = NULL;
6979 	kfree(table);
6980 
6981 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6982 }
6983 
6984 static int addrconf_sysctl_register(struct inet6_dev *idev)
6985 {
6986 	int err;
6987 
6988 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6989 		return -EINVAL;
6990 
6991 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6992 				    &ndisc_ifinfo_sysctl_change);
6993 	if (err)
6994 		return err;
6995 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6996 					 idev, &idev->cnf);
6997 	if (err)
6998 		neigh_sysctl_unregister(idev->nd_parms);
6999 
7000 	return err;
7001 }
7002 
7003 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7004 {
7005 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7006 				     idev->dev->ifindex);
7007 	neigh_sysctl_unregister(idev->nd_parms);
7008 }
7009 
7010 
7011 #endif
7012 
7013 static int __net_init addrconf_init_net(struct net *net)
7014 {
7015 	int err = -ENOMEM;
7016 	struct ipv6_devconf *all, *dflt;
7017 
7018 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7019 	if (!all)
7020 		goto err_alloc_all;
7021 
7022 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7023 	if (!dflt)
7024 		goto err_alloc_dflt;
7025 
7026 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7027 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
7028 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
7029 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
7030 	}
7031 
7032 	/* these will be inherited by all namespaces */
7033 	dflt->autoconf = ipv6_defaults.autoconf;
7034 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7035 
7036 	dflt->stable_secret.initialized = false;
7037 	all->stable_secret.initialized = false;
7038 
7039 	net->ipv6.devconf_all = all;
7040 	net->ipv6.devconf_dflt = dflt;
7041 
7042 #ifdef CONFIG_SYSCTL
7043 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7044 	if (err < 0)
7045 		goto err_reg_all;
7046 
7047 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7048 	if (err < 0)
7049 		goto err_reg_dflt;
7050 #endif
7051 	return 0;
7052 
7053 #ifdef CONFIG_SYSCTL
7054 err_reg_dflt:
7055 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7056 err_reg_all:
7057 	kfree(dflt);
7058 #endif
7059 err_alloc_dflt:
7060 	kfree(all);
7061 err_alloc_all:
7062 	return err;
7063 }
7064 
7065 static void __net_exit addrconf_exit_net(struct net *net)
7066 {
7067 #ifdef CONFIG_SYSCTL
7068 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7069 				     NETCONFA_IFINDEX_DEFAULT);
7070 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7071 				     NETCONFA_IFINDEX_ALL);
7072 #endif
7073 	kfree(net->ipv6.devconf_dflt);
7074 	kfree(net->ipv6.devconf_all);
7075 }
7076 
7077 static struct pernet_operations addrconf_ops = {
7078 	.init = addrconf_init_net,
7079 	.exit = addrconf_exit_net,
7080 };
7081 
7082 static struct rtnl_af_ops inet6_ops __read_mostly = {
7083 	.family		  = AF_INET6,
7084 	.fill_link_af	  = inet6_fill_link_af,
7085 	.get_link_af_size = inet6_get_link_af_size,
7086 	.validate_link_af = inet6_validate_link_af,
7087 	.set_link_af	  = inet6_set_link_af,
7088 };
7089 
7090 /*
7091  *	Init / cleanup code
7092  */
7093 
7094 int __init addrconf_init(void)
7095 {
7096 	struct inet6_dev *idev;
7097 	int i, err;
7098 
7099 	err = ipv6_addr_label_init();
7100 	if (err < 0) {
7101 		pr_crit("%s: cannot initialize default policy table: %d\n",
7102 			__func__, err);
7103 		goto out;
7104 	}
7105 
7106 	err = register_pernet_subsys(&addrconf_ops);
7107 	if (err < 0)
7108 		goto out_addrlabel;
7109 
7110 	addrconf_wq = create_workqueue("ipv6_addrconf");
7111 	if (!addrconf_wq) {
7112 		err = -ENOMEM;
7113 		goto out_nowq;
7114 	}
7115 
7116 	/* The addrconf netdev notifier requires that loopback_dev
7117 	 * has it's ipv6 private information allocated and setup
7118 	 * before it can bring up and give link-local addresses
7119 	 * to other devices which are up.
7120 	 *
7121 	 * Unfortunately, loopback_dev is not necessarily the first
7122 	 * entry in the global dev_base list of net devices.  In fact,
7123 	 * it is likely to be the very last entry on that list.
7124 	 * So this causes the notifier registry below to try and
7125 	 * give link-local addresses to all devices besides loopback_dev
7126 	 * first, then loopback_dev, which cases all the non-loopback_dev
7127 	 * devices to fail to get a link-local address.
7128 	 *
7129 	 * So, as a temporary fix, allocate the ipv6 structure for
7130 	 * loopback_dev first by hand.
7131 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7132 	 * device and it being up should be removed.
7133 	 */
7134 	rtnl_lock();
7135 	idev = ipv6_add_dev(init_net.loopback_dev);
7136 	rtnl_unlock();
7137 	if (IS_ERR(idev)) {
7138 		err = PTR_ERR(idev);
7139 		goto errlo;
7140 	}
7141 
7142 	ip6_route_init_special_entries();
7143 
7144 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7145 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7146 
7147 	register_netdevice_notifier(&ipv6_dev_notf);
7148 
7149 	addrconf_verify();
7150 
7151 	rtnl_af_register(&inet6_ops);
7152 
7153 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7154 				   NULL, inet6_dump_ifinfo, 0);
7155 	if (err < 0)
7156 		goto errout;
7157 
7158 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7159 				   inet6_rtm_newaddr, NULL, 0);
7160 	if (err < 0)
7161 		goto errout;
7162 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7163 				   inet6_rtm_deladdr, NULL, 0);
7164 	if (err < 0)
7165 		goto errout;
7166 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7167 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7168 				   RTNL_FLAG_DOIT_UNLOCKED);
7169 	if (err < 0)
7170 		goto errout;
7171 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7172 				   NULL, inet6_dump_ifmcaddr, 0);
7173 	if (err < 0)
7174 		goto errout;
7175 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7176 				   NULL, inet6_dump_ifacaddr, 0);
7177 	if (err < 0)
7178 		goto errout;
7179 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7180 				   inet6_netconf_get_devconf,
7181 				   inet6_netconf_dump_devconf,
7182 				   RTNL_FLAG_DOIT_UNLOCKED);
7183 	if (err < 0)
7184 		goto errout;
7185 	err = ipv6_addr_label_rtnl_register();
7186 	if (err < 0)
7187 		goto errout;
7188 
7189 	return 0;
7190 errout:
7191 	rtnl_unregister_all(PF_INET6);
7192 	rtnl_af_unregister(&inet6_ops);
7193 	unregister_netdevice_notifier(&ipv6_dev_notf);
7194 errlo:
7195 	destroy_workqueue(addrconf_wq);
7196 out_nowq:
7197 	unregister_pernet_subsys(&addrconf_ops);
7198 out_addrlabel:
7199 	ipv6_addr_label_cleanup();
7200 out:
7201 	return err;
7202 }
7203 
7204 void addrconf_cleanup(void)
7205 {
7206 	struct net_device *dev;
7207 	int i;
7208 
7209 	unregister_netdevice_notifier(&ipv6_dev_notf);
7210 	unregister_pernet_subsys(&addrconf_ops);
7211 	ipv6_addr_label_cleanup();
7212 
7213 	rtnl_af_unregister(&inet6_ops);
7214 
7215 	rtnl_lock();
7216 
7217 	/* clean dev list */
7218 	for_each_netdev(&init_net, dev) {
7219 		if (__in6_dev_get(dev) == NULL)
7220 			continue;
7221 		addrconf_ifdown(dev, 1);
7222 	}
7223 	addrconf_ifdown(init_net.loopback_dev, 2);
7224 
7225 	/*
7226 	 *	Check hash table.
7227 	 */
7228 	spin_lock_bh(&addrconf_hash_lock);
7229 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7230 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7231 	spin_unlock_bh(&addrconf_hash_lock);
7232 	cancel_delayed_work(&addr_chk_work);
7233 	rtnl_unlock();
7234 
7235 	destroy_workqueue(addrconf_wq);
7236 }
7237