xref: /openbmc/linux/net/ipv6/addrconf.c (revision e0d07278)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
139 
140 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
141 static int ipv6_count_addresses(const struct inet6_dev *idev);
142 static int ipv6_generate_stable_address(struct in6_addr *addr,
143 					u8 dad_count,
144 					const struct inet6_dev *idev);
145 
146 #define IN6_ADDR_HSIZE_SHIFT	8
147 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
148 /*
149  *	Configured unicast address hash table
150  */
151 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
152 static DEFINE_SPINLOCK(addrconf_hash_lock);
153 
154 static void addrconf_verify(void);
155 static void addrconf_verify_rtnl(void);
156 static void addrconf_verify_work(struct work_struct *);
157 
158 static struct workqueue_struct *addrconf_wq;
159 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
160 
161 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
162 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
163 
164 static void addrconf_type_change(struct net_device *dev,
165 				 unsigned long event);
166 static int addrconf_ifdown(struct net_device *dev, bool unregister);
167 
168 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
169 						  int plen,
170 						  const struct net_device *dev,
171 						  u32 flags, u32 noflags,
172 						  bool no_gw);
173 
174 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
175 static void addrconf_dad_work(struct work_struct *w);
176 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
177 				   bool send_na);
178 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
179 static void addrconf_rs_timer(struct timer_list *t);
180 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
181 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 
183 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
184 				struct prefix_info *pinfo);
185 
186 static struct ipv6_devconf ipv6_devconf __read_mostly = {
187 	.forwarding		= 0,
188 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
189 	.mtu6			= IPV6_MIN_MTU,
190 	.accept_ra		= 1,
191 	.accept_redirects	= 1,
192 	.autoconf		= 1,
193 	.force_mld_version	= 0,
194 	.mldv1_unsolicited_report_interval = 10 * HZ,
195 	.mldv2_unsolicited_report_interval = HZ,
196 	.dad_transmits		= 1,
197 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
198 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
199 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
200 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
201 	.use_tempaddr		= 0,
202 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
203 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
204 	.regen_max_retry	= REGEN_MAX_RETRY,
205 	.max_desync_factor	= MAX_DESYNC_FACTOR,
206 	.max_addresses		= IPV6_MAX_ADDRESSES,
207 	.accept_ra_defrtr	= 1,
208 	.accept_ra_from_local	= 0,
209 	.accept_ra_min_hop_limit= 1,
210 	.accept_ra_pinfo	= 1,
211 #ifdef CONFIG_IPV6_ROUTER_PREF
212 	.accept_ra_rtr_pref	= 1,
213 	.rtr_probe_interval	= 60 * HZ,
214 #ifdef CONFIG_IPV6_ROUTE_INFO
215 	.accept_ra_rt_info_min_plen = 0,
216 	.accept_ra_rt_info_max_plen = 0,
217 #endif
218 #endif
219 	.proxy_ndp		= 0,
220 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
221 	.disable_ipv6		= 0,
222 	.accept_dad		= 0,
223 	.suppress_frag_ndisc	= 1,
224 	.accept_ra_mtu		= 1,
225 	.stable_secret		= {
226 		.initialized = false,
227 	},
228 	.use_oif_addrs_only	= 0,
229 	.ignore_routes_with_linkdown = 0,
230 	.keep_addr_on_down	= 0,
231 	.seg6_enabled		= 0,
232 #ifdef CONFIG_IPV6_SEG6_HMAC
233 	.seg6_require_hmac	= 0,
234 #endif
235 	.enhanced_dad           = 1,
236 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
237 	.disable_policy		= 0,
238 	.rpl_seg_enabled	= 0,
239 };
240 
241 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
242 	.forwarding		= 0,
243 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
244 	.mtu6			= IPV6_MIN_MTU,
245 	.accept_ra		= 1,
246 	.accept_redirects	= 1,
247 	.autoconf		= 1,
248 	.force_mld_version	= 0,
249 	.mldv1_unsolicited_report_interval = 10 * HZ,
250 	.mldv2_unsolicited_report_interval = HZ,
251 	.dad_transmits		= 1,
252 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
253 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
254 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
255 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
256 	.use_tempaddr		= 0,
257 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
258 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
259 	.regen_max_retry	= REGEN_MAX_RETRY,
260 	.max_desync_factor	= MAX_DESYNC_FACTOR,
261 	.max_addresses		= IPV6_MAX_ADDRESSES,
262 	.accept_ra_defrtr	= 1,
263 	.accept_ra_from_local	= 0,
264 	.accept_ra_min_hop_limit= 1,
265 	.accept_ra_pinfo	= 1,
266 #ifdef CONFIG_IPV6_ROUTER_PREF
267 	.accept_ra_rtr_pref	= 1,
268 	.rtr_probe_interval	= 60 * HZ,
269 #ifdef CONFIG_IPV6_ROUTE_INFO
270 	.accept_ra_rt_info_min_plen = 0,
271 	.accept_ra_rt_info_max_plen = 0,
272 #endif
273 #endif
274 	.proxy_ndp		= 0,
275 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
276 	.disable_ipv6		= 0,
277 	.accept_dad		= 1,
278 	.suppress_frag_ndisc	= 1,
279 	.accept_ra_mtu		= 1,
280 	.stable_secret		= {
281 		.initialized = false,
282 	},
283 	.use_oif_addrs_only	= 0,
284 	.ignore_routes_with_linkdown = 0,
285 	.keep_addr_on_down	= 0,
286 	.seg6_enabled		= 0,
287 #ifdef CONFIG_IPV6_SEG6_HMAC
288 	.seg6_require_hmac	= 0,
289 #endif
290 	.enhanced_dad           = 1,
291 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
292 	.disable_policy		= 0,
293 	.rpl_seg_enabled	= 0,
294 };
295 
296 /* Check if link is ready: is it up and is a valid qdisc available */
297 static inline bool addrconf_link_ready(const struct net_device *dev)
298 {
299 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
300 }
301 
302 static void addrconf_del_rs_timer(struct inet6_dev *idev)
303 {
304 	if (del_timer(&idev->rs_timer))
305 		__in6_dev_put(idev);
306 }
307 
308 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
309 {
310 	if (cancel_delayed_work(&ifp->dad_work))
311 		__in6_ifa_put(ifp);
312 }
313 
314 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
315 				  unsigned long when)
316 {
317 	if (!timer_pending(&idev->rs_timer))
318 		in6_dev_hold(idev);
319 	mod_timer(&idev->rs_timer, jiffies + when);
320 }
321 
322 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
323 				   unsigned long delay)
324 {
325 	in6_ifa_hold(ifp);
326 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
327 		in6_ifa_put(ifp);
328 }
329 
330 static int snmp6_alloc_dev(struct inet6_dev *idev)
331 {
332 	int i;
333 
334 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
335 	if (!idev->stats.ipv6)
336 		goto err_ip;
337 
338 	for_each_possible_cpu(i) {
339 		struct ipstats_mib *addrconf_stats;
340 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
341 		u64_stats_init(&addrconf_stats->syncp);
342 	}
343 
344 
345 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
346 					GFP_KERNEL);
347 	if (!idev->stats.icmpv6dev)
348 		goto err_icmp;
349 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
350 					   GFP_KERNEL);
351 	if (!idev->stats.icmpv6msgdev)
352 		goto err_icmpmsg;
353 
354 	return 0;
355 
356 err_icmpmsg:
357 	kfree(idev->stats.icmpv6dev);
358 err_icmp:
359 	free_percpu(idev->stats.ipv6);
360 err_ip:
361 	return -ENOMEM;
362 }
363 
364 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
365 {
366 	struct inet6_dev *ndev;
367 	int err = -ENOMEM;
368 
369 	ASSERT_RTNL();
370 
371 	if (dev->mtu < IPV6_MIN_MTU)
372 		return ERR_PTR(-EINVAL);
373 
374 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
375 	if (!ndev)
376 		return ERR_PTR(err);
377 
378 	rwlock_init(&ndev->lock);
379 	ndev->dev = dev;
380 	INIT_LIST_HEAD(&ndev->addr_list);
381 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
382 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
383 
384 	if (ndev->cnf.stable_secret.initialized)
385 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
386 
387 	ndev->cnf.mtu6 = dev->mtu;
388 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
389 	if (!ndev->nd_parms) {
390 		kfree(ndev);
391 		return ERR_PTR(err);
392 	}
393 	if (ndev->cnf.forwarding)
394 		dev_disable_lro(dev);
395 	/* We refer to the device */
396 	dev_hold(dev);
397 
398 	if (snmp6_alloc_dev(ndev) < 0) {
399 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
400 			   __func__);
401 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
402 		dev_put(dev);
403 		kfree(ndev);
404 		return ERR_PTR(err);
405 	}
406 
407 	if (snmp6_register_dev(ndev) < 0) {
408 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
409 			   __func__, dev->name);
410 		goto err_release;
411 	}
412 
413 	/* One reference from device. */
414 	refcount_set(&ndev->refcnt, 1);
415 
416 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
417 		ndev->cnf.accept_dad = -1;
418 
419 #if IS_ENABLED(CONFIG_IPV6_SIT)
420 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
421 		pr_info("%s: Disabled Multicast RS\n", dev->name);
422 		ndev->cnf.rtr_solicits = 0;
423 	}
424 #endif
425 
426 	INIT_LIST_HEAD(&ndev->tempaddr_list);
427 	ndev->desync_factor = U32_MAX;
428 	if ((dev->flags&IFF_LOOPBACK) ||
429 	    dev->type == ARPHRD_TUNNEL ||
430 	    dev->type == ARPHRD_TUNNEL6 ||
431 	    dev->type == ARPHRD_SIT ||
432 	    dev->type == ARPHRD_NONE) {
433 		ndev->cnf.use_tempaddr = -1;
434 	}
435 
436 	ndev->token = in6addr_any;
437 
438 	if (netif_running(dev) && addrconf_link_ready(dev))
439 		ndev->if_flags |= IF_READY;
440 
441 	ipv6_mc_init_dev(ndev);
442 	ndev->tstamp = jiffies;
443 	err = addrconf_sysctl_register(ndev);
444 	if (err) {
445 		ipv6_mc_destroy_dev(ndev);
446 		snmp6_unregister_dev(ndev);
447 		goto err_release;
448 	}
449 	/* protected by rtnl_lock */
450 	rcu_assign_pointer(dev->ip6_ptr, ndev);
451 
452 	/* Join interface-local all-node multicast group */
453 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
454 
455 	/* Join all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
457 
458 	/* Join all-router multicast group if forwarding is set */
459 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
460 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
461 
462 	return ndev;
463 
464 err_release:
465 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
466 	ndev->dead = 1;
467 	in6_dev_finish_destroy(ndev);
468 	return ERR_PTR(err);
469 }
470 
471 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
472 {
473 	struct inet6_dev *idev;
474 
475 	ASSERT_RTNL();
476 
477 	idev = __in6_dev_get(dev);
478 	if (!idev) {
479 		idev = ipv6_add_dev(dev);
480 		if (IS_ERR(idev))
481 			return idev;
482 	}
483 
484 	if (dev->flags&IFF_UP)
485 		ipv6_mc_up(idev);
486 	return idev;
487 }
488 
489 static int inet6_netconf_msgsize_devconf(int type)
490 {
491 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
492 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
493 	bool all = false;
494 
495 	if (type == NETCONFA_ALL)
496 		all = true;
497 
498 	if (all || type == NETCONFA_FORWARDING)
499 		size += nla_total_size(4);
500 #ifdef CONFIG_IPV6_MROUTE
501 	if (all || type == NETCONFA_MC_FORWARDING)
502 		size += nla_total_size(4);
503 #endif
504 	if (all || type == NETCONFA_PROXY_NEIGH)
505 		size += nla_total_size(4);
506 
507 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
508 		size += nla_total_size(4);
509 
510 	return size;
511 }
512 
513 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
514 				      struct ipv6_devconf *devconf, u32 portid,
515 				      u32 seq, int event, unsigned int flags,
516 				      int type)
517 {
518 	struct nlmsghdr  *nlh;
519 	struct netconfmsg *ncm;
520 	bool all = false;
521 
522 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
523 			flags);
524 	if (!nlh)
525 		return -EMSGSIZE;
526 
527 	if (type == NETCONFA_ALL)
528 		all = true;
529 
530 	ncm = nlmsg_data(nlh);
531 	ncm->ncm_family = AF_INET6;
532 
533 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
534 		goto nla_put_failure;
535 
536 	if (!devconf)
537 		goto out;
538 
539 	if ((all || type == NETCONFA_FORWARDING) &&
540 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
541 		goto nla_put_failure;
542 #ifdef CONFIG_IPV6_MROUTE
543 	if ((all || type == NETCONFA_MC_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
545 			devconf->mc_forwarding) < 0)
546 		goto nla_put_failure;
547 #endif
548 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
549 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
550 		goto nla_put_failure;
551 
552 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
553 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
554 			devconf->ignore_routes_with_linkdown) < 0)
555 		goto nla_put_failure;
556 
557 out:
558 	nlmsg_end(skb, nlh);
559 	return 0;
560 
561 nla_put_failure:
562 	nlmsg_cancel(skb, nlh);
563 	return -EMSGSIZE;
564 }
565 
566 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
567 				  int ifindex, struct ipv6_devconf *devconf)
568 {
569 	struct sk_buff *skb;
570 	int err = -ENOBUFS;
571 
572 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
573 	if (!skb)
574 		goto errout;
575 
576 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
577 					 event, 0, type);
578 	if (err < 0) {
579 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
580 		WARN_ON(err == -EMSGSIZE);
581 		kfree_skb(skb);
582 		goto errout;
583 	}
584 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
585 	return;
586 errout:
587 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
588 }
589 
590 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
591 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
592 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
593 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
594 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
595 };
596 
597 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
598 				       const struct nlmsghdr *nlh,
599 				       struct nlattr **tb,
600 				       struct netlink_ext_ack *extack)
601 {
602 	int i, err;
603 
604 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
605 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
606 		return -EINVAL;
607 	}
608 
609 	if (!netlink_strict_get_check(skb))
610 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
611 					      tb, NETCONFA_MAX,
612 					      devconf_ipv6_policy, extack);
613 
614 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
615 					    tb, NETCONFA_MAX,
616 					    devconf_ipv6_policy, extack);
617 	if (err)
618 		return err;
619 
620 	for (i = 0; i <= NETCONFA_MAX; i++) {
621 		if (!tb[i])
622 			continue;
623 
624 		switch (i) {
625 		case NETCONFA_IFINDEX:
626 			break;
627 		default:
628 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
629 			return -EINVAL;
630 		}
631 	}
632 
633 	return 0;
634 }
635 
636 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
637 				     struct nlmsghdr *nlh,
638 				     struct netlink_ext_ack *extack)
639 {
640 	struct net *net = sock_net(in_skb->sk);
641 	struct nlattr *tb[NETCONFA_MAX+1];
642 	struct inet6_dev *in6_dev = NULL;
643 	struct net_device *dev = NULL;
644 	struct sk_buff *skb;
645 	struct ipv6_devconf *devconf;
646 	int ifindex;
647 	int err;
648 
649 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
650 	if (err < 0)
651 		return err;
652 
653 	if (!tb[NETCONFA_IFINDEX])
654 		return -EINVAL;
655 
656 	err = -EINVAL;
657 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
658 	switch (ifindex) {
659 	case NETCONFA_IFINDEX_ALL:
660 		devconf = net->ipv6.devconf_all;
661 		break;
662 	case NETCONFA_IFINDEX_DEFAULT:
663 		devconf = net->ipv6.devconf_dflt;
664 		break;
665 	default:
666 		dev = dev_get_by_index(net, ifindex);
667 		if (!dev)
668 			return -EINVAL;
669 		in6_dev = in6_dev_get(dev);
670 		if (!in6_dev)
671 			goto errout;
672 		devconf = &in6_dev->cnf;
673 		break;
674 	}
675 
676 	err = -ENOBUFS;
677 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
678 	if (!skb)
679 		goto errout;
680 
681 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
682 					 NETLINK_CB(in_skb).portid,
683 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
684 					 NETCONFA_ALL);
685 	if (err < 0) {
686 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
687 		WARN_ON(err == -EMSGSIZE);
688 		kfree_skb(skb);
689 		goto errout;
690 	}
691 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
692 errout:
693 	if (in6_dev)
694 		in6_dev_put(in6_dev);
695 	if (dev)
696 		dev_put(dev);
697 	return err;
698 }
699 
700 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
701 				      struct netlink_callback *cb)
702 {
703 	const struct nlmsghdr *nlh = cb->nlh;
704 	struct net *net = sock_net(skb->sk);
705 	int h, s_h;
706 	int idx, s_idx;
707 	struct net_device *dev;
708 	struct inet6_dev *idev;
709 	struct hlist_head *head;
710 
711 	if (cb->strict_check) {
712 		struct netlink_ext_ack *extack = cb->extack;
713 		struct netconfmsg *ncm;
714 
715 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
716 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
717 			return -EINVAL;
718 		}
719 
720 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
721 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
722 			return -EINVAL;
723 		}
724 	}
725 
726 	s_h = cb->args[0];
727 	s_idx = idx = cb->args[1];
728 
729 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
730 		idx = 0;
731 		head = &net->dev_index_head[h];
732 		rcu_read_lock();
733 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
734 			  net->dev_base_seq;
735 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
736 			if (idx < s_idx)
737 				goto cont;
738 			idev = __in6_dev_get(dev);
739 			if (!idev)
740 				goto cont;
741 
742 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
743 						       &idev->cnf,
744 						       NETLINK_CB(cb->skb).portid,
745 						       nlh->nlmsg_seq,
746 						       RTM_NEWNETCONF,
747 						       NLM_F_MULTI,
748 						       NETCONFA_ALL) < 0) {
749 				rcu_read_unlock();
750 				goto done;
751 			}
752 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
753 cont:
754 			idx++;
755 		}
756 		rcu_read_unlock();
757 	}
758 	if (h == NETDEV_HASHENTRIES) {
759 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
760 					       net->ipv6.devconf_all,
761 					       NETLINK_CB(cb->skb).portid,
762 					       nlh->nlmsg_seq,
763 					       RTM_NEWNETCONF, NLM_F_MULTI,
764 					       NETCONFA_ALL) < 0)
765 			goto done;
766 		else
767 			h++;
768 	}
769 	if (h == NETDEV_HASHENTRIES + 1) {
770 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
771 					       net->ipv6.devconf_dflt,
772 					       NETLINK_CB(cb->skb).portid,
773 					       nlh->nlmsg_seq,
774 					       RTM_NEWNETCONF, NLM_F_MULTI,
775 					       NETCONFA_ALL) < 0)
776 			goto done;
777 		else
778 			h++;
779 	}
780 done:
781 	cb->args[0] = h;
782 	cb->args[1] = idx;
783 
784 	return skb->len;
785 }
786 
787 #ifdef CONFIG_SYSCTL
788 static void dev_forward_change(struct inet6_dev *idev)
789 {
790 	struct net_device *dev;
791 	struct inet6_ifaddr *ifa;
792 
793 	if (!idev)
794 		return;
795 	dev = idev->dev;
796 	if (idev->cnf.forwarding)
797 		dev_disable_lro(dev);
798 	if (dev->flags & IFF_MULTICAST) {
799 		if (idev->cnf.forwarding) {
800 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
801 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
802 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
803 		} else {
804 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
805 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
806 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
807 		}
808 	}
809 
810 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
811 		if (ifa->flags&IFA_F_TENTATIVE)
812 			continue;
813 		if (idev->cnf.forwarding)
814 			addrconf_join_anycast(ifa);
815 		else
816 			addrconf_leave_anycast(ifa);
817 	}
818 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
819 				     NETCONFA_FORWARDING,
820 				     dev->ifindex, &idev->cnf);
821 }
822 
823 
824 static void addrconf_forward_change(struct net *net, __s32 newf)
825 {
826 	struct net_device *dev;
827 	struct inet6_dev *idev;
828 
829 	for_each_netdev(net, dev) {
830 		idev = __in6_dev_get(dev);
831 		if (idev) {
832 			int changed = (!idev->cnf.forwarding) ^ (!newf);
833 			idev->cnf.forwarding = newf;
834 			if (changed)
835 				dev_forward_change(idev);
836 		}
837 	}
838 }
839 
840 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
841 {
842 	struct net *net;
843 	int old;
844 
845 	if (!rtnl_trylock())
846 		return restart_syscall();
847 
848 	net = (struct net *)table->extra2;
849 	old = *p;
850 	*p = newf;
851 
852 	if (p == &net->ipv6.devconf_dflt->forwarding) {
853 		if ((!newf) ^ (!old))
854 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
855 						     NETCONFA_FORWARDING,
856 						     NETCONFA_IFINDEX_DEFAULT,
857 						     net->ipv6.devconf_dflt);
858 		rtnl_unlock();
859 		return 0;
860 	}
861 
862 	if (p == &net->ipv6.devconf_all->forwarding) {
863 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
864 
865 		net->ipv6.devconf_dflt->forwarding = newf;
866 		if ((!newf) ^ (!old_dflt))
867 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
868 						     NETCONFA_FORWARDING,
869 						     NETCONFA_IFINDEX_DEFAULT,
870 						     net->ipv6.devconf_dflt);
871 
872 		addrconf_forward_change(net, newf);
873 		if ((!newf) ^ (!old))
874 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
875 						     NETCONFA_FORWARDING,
876 						     NETCONFA_IFINDEX_ALL,
877 						     net->ipv6.devconf_all);
878 	} else if ((!newf) ^ (!old))
879 		dev_forward_change((struct inet6_dev *)table->extra1);
880 	rtnl_unlock();
881 
882 	if (newf)
883 		rt6_purge_dflt_routers(net);
884 	return 1;
885 }
886 
887 static void addrconf_linkdown_change(struct net *net, __s32 newf)
888 {
889 	struct net_device *dev;
890 	struct inet6_dev *idev;
891 
892 	for_each_netdev(net, dev) {
893 		idev = __in6_dev_get(dev);
894 		if (idev) {
895 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
896 
897 			idev->cnf.ignore_routes_with_linkdown = newf;
898 			if (changed)
899 				inet6_netconf_notify_devconf(dev_net(dev),
900 							     RTM_NEWNETCONF,
901 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
902 							     dev->ifindex,
903 							     &idev->cnf);
904 		}
905 	}
906 }
907 
908 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
909 {
910 	struct net *net;
911 	int old;
912 
913 	if (!rtnl_trylock())
914 		return restart_syscall();
915 
916 	net = (struct net *)table->extra2;
917 	old = *p;
918 	*p = newf;
919 
920 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
921 		if ((!newf) ^ (!old))
922 			inet6_netconf_notify_devconf(net,
923 						     RTM_NEWNETCONF,
924 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
925 						     NETCONFA_IFINDEX_DEFAULT,
926 						     net->ipv6.devconf_dflt);
927 		rtnl_unlock();
928 		return 0;
929 	}
930 
931 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
932 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
933 		addrconf_linkdown_change(net, newf);
934 		if ((!newf) ^ (!old))
935 			inet6_netconf_notify_devconf(net,
936 						     RTM_NEWNETCONF,
937 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
938 						     NETCONFA_IFINDEX_ALL,
939 						     net->ipv6.devconf_all);
940 	}
941 	rtnl_unlock();
942 
943 	return 1;
944 }
945 
946 #endif
947 
948 /* Nobody refers to this ifaddr, destroy it */
949 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
950 {
951 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
952 
953 #ifdef NET_REFCNT_DEBUG
954 	pr_debug("%s\n", __func__);
955 #endif
956 
957 	in6_dev_put(ifp->idev);
958 
959 	if (cancel_delayed_work(&ifp->dad_work))
960 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
961 			  ifp);
962 
963 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
964 		pr_warn("Freeing alive inet6 address %p\n", ifp);
965 		return;
966 	}
967 
968 	kfree_rcu(ifp, rcu);
969 }
970 
971 static void
972 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
973 {
974 	struct list_head *p;
975 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
976 
977 	/*
978 	 * Each device address list is sorted in order of scope -
979 	 * global before linklocal.
980 	 */
981 	list_for_each(p, &idev->addr_list) {
982 		struct inet6_ifaddr *ifa
983 			= list_entry(p, struct inet6_ifaddr, if_list);
984 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
985 			break;
986 	}
987 
988 	list_add_tail_rcu(&ifp->if_list, p);
989 }
990 
991 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
992 {
993 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
994 
995 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
996 }
997 
998 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
999 			       struct net_device *dev, unsigned int hash)
1000 {
1001 	struct inet6_ifaddr *ifp;
1002 
1003 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1004 		if (!net_eq(dev_net(ifp->idev->dev), net))
1005 			continue;
1006 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1007 			if (!dev || ifp->idev->dev == dev)
1008 				return true;
1009 		}
1010 	}
1011 	return false;
1012 }
1013 
1014 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1015 {
1016 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1017 	int err = 0;
1018 
1019 	spin_lock(&addrconf_hash_lock);
1020 
1021 	/* Ignore adding duplicate addresses on an interface */
1022 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1023 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1024 		err = -EEXIST;
1025 	} else {
1026 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1027 	}
1028 
1029 	spin_unlock(&addrconf_hash_lock);
1030 
1031 	return err;
1032 }
1033 
1034 /* On success it returns ifp with increased reference count */
1035 
1036 static struct inet6_ifaddr *
1037 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1038 	      bool can_block, struct netlink_ext_ack *extack)
1039 {
1040 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1041 	int addr_type = ipv6_addr_type(cfg->pfx);
1042 	struct net *net = dev_net(idev->dev);
1043 	struct inet6_ifaddr *ifa = NULL;
1044 	struct fib6_info *f6i = NULL;
1045 	int err = 0;
1046 
1047 	if (addr_type == IPV6_ADDR_ANY ||
1048 	    (addr_type & IPV6_ADDR_MULTICAST &&
1049 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1050 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1051 	     !netif_is_l3_master(idev->dev) &&
1052 	     addr_type & IPV6_ADDR_LOOPBACK))
1053 		return ERR_PTR(-EADDRNOTAVAIL);
1054 
1055 	if (idev->dead) {
1056 		err = -ENODEV;			/*XXX*/
1057 		goto out;
1058 	}
1059 
1060 	if (idev->cnf.disable_ipv6) {
1061 		err = -EACCES;
1062 		goto out;
1063 	}
1064 
1065 	/* validator notifier needs to be blocking;
1066 	 * do not call in atomic context
1067 	 */
1068 	if (can_block) {
1069 		struct in6_validator_info i6vi = {
1070 			.i6vi_addr = *cfg->pfx,
1071 			.i6vi_dev = idev,
1072 			.extack = extack,
1073 		};
1074 
1075 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1076 		err = notifier_to_errno(err);
1077 		if (err < 0)
1078 			goto out;
1079 	}
1080 
1081 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1082 	if (!ifa) {
1083 		err = -ENOBUFS;
1084 		goto out;
1085 	}
1086 
1087 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1088 	if (IS_ERR(f6i)) {
1089 		err = PTR_ERR(f6i);
1090 		f6i = NULL;
1091 		goto out;
1092 	}
1093 
1094 	if (net->ipv6.devconf_all->disable_policy ||
1095 	    idev->cnf.disable_policy)
1096 		f6i->dst_nopolicy = true;
1097 
1098 	neigh_parms_data_state_setall(idev->nd_parms);
1099 
1100 	ifa->addr = *cfg->pfx;
1101 	if (cfg->peer_pfx)
1102 		ifa->peer_addr = *cfg->peer_pfx;
1103 
1104 	spin_lock_init(&ifa->lock);
1105 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1106 	INIT_HLIST_NODE(&ifa->addr_lst);
1107 	ifa->scope = cfg->scope;
1108 	ifa->prefix_len = cfg->plen;
1109 	ifa->rt_priority = cfg->rt_priority;
1110 	ifa->flags = cfg->ifa_flags;
1111 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1112 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1113 		ifa->flags |= IFA_F_TENTATIVE;
1114 	ifa->valid_lft = cfg->valid_lft;
1115 	ifa->prefered_lft = cfg->preferred_lft;
1116 	ifa->cstamp = ifa->tstamp = jiffies;
1117 	ifa->tokenized = false;
1118 
1119 	ifa->rt = f6i;
1120 
1121 	ifa->idev = idev;
1122 	in6_dev_hold(idev);
1123 
1124 	/* For caller */
1125 	refcount_set(&ifa->refcnt, 1);
1126 
1127 	rcu_read_lock_bh();
1128 
1129 	err = ipv6_add_addr_hash(idev->dev, ifa);
1130 	if (err < 0) {
1131 		rcu_read_unlock_bh();
1132 		goto out;
1133 	}
1134 
1135 	write_lock(&idev->lock);
1136 
1137 	/* Add to inet6_dev unicast addr list. */
1138 	ipv6_link_dev_addr(idev, ifa);
1139 
1140 	if (ifa->flags&IFA_F_TEMPORARY) {
1141 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1142 		in6_ifa_hold(ifa);
1143 	}
1144 
1145 	in6_ifa_hold(ifa);
1146 	write_unlock(&idev->lock);
1147 
1148 	rcu_read_unlock_bh();
1149 
1150 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1151 out:
1152 	if (unlikely(err < 0)) {
1153 		fib6_info_release(f6i);
1154 
1155 		if (ifa) {
1156 			if (ifa->idev)
1157 				in6_dev_put(ifa->idev);
1158 			kfree(ifa);
1159 		}
1160 		ifa = ERR_PTR(err);
1161 	}
1162 
1163 	return ifa;
1164 }
1165 
1166 enum cleanup_prefix_rt_t {
1167 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1168 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1169 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1170 };
1171 
1172 /*
1173  * Check, whether the prefix for ifp would still need a prefix route
1174  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1175  * constants.
1176  *
1177  * 1) we don't purge prefix if address was not permanent.
1178  *    prefix is managed by its own lifetime.
1179  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1180  * 3) if there are no addresses, delete prefix.
1181  * 4) if there are still other permanent address(es),
1182  *    corresponding prefix is still permanent.
1183  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1184  *    don't purge the prefix, assume user space is managing it.
1185  * 6) otherwise, update prefix lifetime to the
1186  *    longest valid lifetime among the corresponding
1187  *    addresses on the device.
1188  *    Note: subsequent RA will update lifetime.
1189  **/
1190 static enum cleanup_prefix_rt_t
1191 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1192 {
1193 	struct inet6_ifaddr *ifa;
1194 	struct inet6_dev *idev = ifp->idev;
1195 	unsigned long lifetime;
1196 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1197 
1198 	*expires = jiffies;
1199 
1200 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1201 		if (ifa == ifp)
1202 			continue;
1203 		if (ifa->prefix_len != ifp->prefix_len ||
1204 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1205 				       ifp->prefix_len))
1206 			continue;
1207 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1208 			return CLEANUP_PREFIX_RT_NOP;
1209 
1210 		action = CLEANUP_PREFIX_RT_EXPIRE;
1211 
1212 		spin_lock(&ifa->lock);
1213 
1214 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1215 		/*
1216 		 * Note: Because this address is
1217 		 * not permanent, lifetime <
1218 		 * LONG_MAX / HZ here.
1219 		 */
1220 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1221 			*expires = ifa->tstamp + lifetime * HZ;
1222 		spin_unlock(&ifa->lock);
1223 	}
1224 
1225 	return action;
1226 }
1227 
1228 static void
1229 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1230 		     bool del_rt, bool del_peer)
1231 {
1232 	struct fib6_info *f6i;
1233 
1234 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1235 					ifp->prefix_len,
1236 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1237 	if (f6i) {
1238 		if (del_rt)
1239 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1240 		else {
1241 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1242 				fib6_set_expires(f6i, expires);
1243 			fib6_info_release(f6i);
1244 		}
1245 	}
1246 }
1247 
1248 
1249 /* This function wants to get referenced ifp and releases it before return */
1250 
1251 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1252 {
1253 	int state;
1254 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1255 	unsigned long expires;
1256 
1257 	ASSERT_RTNL();
1258 
1259 	spin_lock_bh(&ifp->lock);
1260 	state = ifp->state;
1261 	ifp->state = INET6_IFADDR_STATE_DEAD;
1262 	spin_unlock_bh(&ifp->lock);
1263 
1264 	if (state == INET6_IFADDR_STATE_DEAD)
1265 		goto out;
1266 
1267 	spin_lock_bh(&addrconf_hash_lock);
1268 	hlist_del_init_rcu(&ifp->addr_lst);
1269 	spin_unlock_bh(&addrconf_hash_lock);
1270 
1271 	write_lock_bh(&ifp->idev->lock);
1272 
1273 	if (ifp->flags&IFA_F_TEMPORARY) {
1274 		list_del(&ifp->tmp_list);
1275 		if (ifp->ifpub) {
1276 			in6_ifa_put(ifp->ifpub);
1277 			ifp->ifpub = NULL;
1278 		}
1279 		__in6_ifa_put(ifp);
1280 	}
1281 
1282 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1283 		action = check_cleanup_prefix_route(ifp, &expires);
1284 
1285 	list_del_rcu(&ifp->if_list);
1286 	__in6_ifa_put(ifp);
1287 
1288 	write_unlock_bh(&ifp->idev->lock);
1289 
1290 	addrconf_del_dad_work(ifp);
1291 
1292 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1293 
1294 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1295 
1296 	if (action != CLEANUP_PREFIX_RT_NOP) {
1297 		cleanup_prefix_route(ifp, expires,
1298 			action == CLEANUP_PREFIX_RT_DEL, false);
1299 	}
1300 
1301 	/* clean up prefsrc entries */
1302 	rt6_remove_prefsrc(ifp);
1303 out:
1304 	in6_ifa_put(ifp);
1305 }
1306 
1307 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1308 {
1309 	struct inet6_dev *idev = ifp->idev;
1310 	unsigned long tmp_tstamp, age;
1311 	unsigned long regen_advance;
1312 	unsigned long now = jiffies;
1313 	s32 cnf_temp_preferred_lft;
1314 	struct inet6_ifaddr *ift;
1315 	struct ifa6_config cfg;
1316 	long max_desync_factor;
1317 	struct in6_addr addr;
1318 	int ret = 0;
1319 
1320 	write_lock_bh(&idev->lock);
1321 
1322 retry:
1323 	in6_dev_hold(idev);
1324 	if (idev->cnf.use_tempaddr <= 0) {
1325 		write_unlock_bh(&idev->lock);
1326 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1327 		in6_dev_put(idev);
1328 		ret = -1;
1329 		goto out;
1330 	}
1331 	spin_lock_bh(&ifp->lock);
1332 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1333 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1334 		spin_unlock_bh(&ifp->lock);
1335 		write_unlock_bh(&idev->lock);
1336 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1337 			__func__);
1338 		in6_dev_put(idev);
1339 		ret = -1;
1340 		goto out;
1341 	}
1342 	in6_ifa_hold(ifp);
1343 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1344 	ipv6_gen_rnd_iid(&addr);
1345 
1346 	age = (now - ifp->tstamp) / HZ;
1347 
1348 	regen_advance = idev->cnf.regen_max_retry *
1349 			idev->cnf.dad_transmits *
1350 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1351 
1352 	/* recalculate max_desync_factor each time and update
1353 	 * idev->desync_factor if it's larger
1354 	 */
1355 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1356 	max_desync_factor = min_t(__u32,
1357 				  idev->cnf.max_desync_factor,
1358 				  cnf_temp_preferred_lft - regen_advance);
1359 
1360 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1361 		if (max_desync_factor > 0) {
1362 			get_random_bytes(&idev->desync_factor,
1363 					 sizeof(idev->desync_factor));
1364 			idev->desync_factor %= max_desync_factor;
1365 		} else {
1366 			idev->desync_factor = 0;
1367 		}
1368 	}
1369 
1370 	memset(&cfg, 0, sizeof(cfg));
1371 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1372 			      idev->cnf.temp_valid_lft + age);
1373 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1374 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1375 
1376 	cfg.plen = ifp->prefix_len;
1377 	tmp_tstamp = ifp->tstamp;
1378 	spin_unlock_bh(&ifp->lock);
1379 
1380 	write_unlock_bh(&idev->lock);
1381 
1382 	/* A temporary address is created only if this calculated Preferred
1383 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1384 	 * an implementation must not create a temporary address with a zero
1385 	 * Preferred Lifetime.
1386 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1387 	 * temporary addresses being generated.
1388 	 */
1389 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1390 	if (cfg.preferred_lft <= regen_advance + age) {
1391 		in6_ifa_put(ifp);
1392 		in6_dev_put(idev);
1393 		ret = -1;
1394 		goto out;
1395 	}
1396 
1397 	cfg.ifa_flags = IFA_F_TEMPORARY;
1398 	/* set in addrconf_prefix_rcv() */
1399 	if (ifp->flags & IFA_F_OPTIMISTIC)
1400 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1401 
1402 	cfg.pfx = &addr;
1403 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1404 
1405 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1406 	if (IS_ERR(ift)) {
1407 		in6_ifa_put(ifp);
1408 		in6_dev_put(idev);
1409 		pr_info("%s: retry temporary address regeneration\n", __func__);
1410 		write_lock_bh(&idev->lock);
1411 		goto retry;
1412 	}
1413 
1414 	spin_lock_bh(&ift->lock);
1415 	ift->ifpub = ifp;
1416 	ift->cstamp = now;
1417 	ift->tstamp = tmp_tstamp;
1418 	spin_unlock_bh(&ift->lock);
1419 
1420 	addrconf_dad_start(ift);
1421 	in6_ifa_put(ift);
1422 	in6_dev_put(idev);
1423 out:
1424 	return ret;
1425 }
1426 
1427 /*
1428  *	Choose an appropriate source address (RFC3484)
1429  */
1430 enum {
1431 	IPV6_SADDR_RULE_INIT = 0,
1432 	IPV6_SADDR_RULE_LOCAL,
1433 	IPV6_SADDR_RULE_SCOPE,
1434 	IPV6_SADDR_RULE_PREFERRED,
1435 #ifdef CONFIG_IPV6_MIP6
1436 	IPV6_SADDR_RULE_HOA,
1437 #endif
1438 	IPV6_SADDR_RULE_OIF,
1439 	IPV6_SADDR_RULE_LABEL,
1440 	IPV6_SADDR_RULE_PRIVACY,
1441 	IPV6_SADDR_RULE_ORCHID,
1442 	IPV6_SADDR_RULE_PREFIX,
1443 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1444 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1445 #endif
1446 	IPV6_SADDR_RULE_MAX
1447 };
1448 
1449 struct ipv6_saddr_score {
1450 	int			rule;
1451 	int			addr_type;
1452 	struct inet6_ifaddr	*ifa;
1453 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1454 	int			scopedist;
1455 	int			matchlen;
1456 };
1457 
1458 struct ipv6_saddr_dst {
1459 	const struct in6_addr *addr;
1460 	int ifindex;
1461 	int scope;
1462 	int label;
1463 	unsigned int prefs;
1464 };
1465 
1466 static inline int ipv6_saddr_preferred(int type)
1467 {
1468 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1469 		return 1;
1470 	return 0;
1471 }
1472 
1473 static bool ipv6_use_optimistic_addr(struct net *net,
1474 				     struct inet6_dev *idev)
1475 {
1476 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1477 	if (!idev)
1478 		return false;
1479 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1480 		return false;
1481 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1482 		return false;
1483 
1484 	return true;
1485 #else
1486 	return false;
1487 #endif
1488 }
1489 
1490 static bool ipv6_allow_optimistic_dad(struct net *net,
1491 				      struct inet6_dev *idev)
1492 {
1493 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1494 	if (!idev)
1495 		return false;
1496 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1497 		return false;
1498 
1499 	return true;
1500 #else
1501 	return false;
1502 #endif
1503 }
1504 
1505 static int ipv6_get_saddr_eval(struct net *net,
1506 			       struct ipv6_saddr_score *score,
1507 			       struct ipv6_saddr_dst *dst,
1508 			       int i)
1509 {
1510 	int ret;
1511 
1512 	if (i <= score->rule) {
1513 		switch (i) {
1514 		case IPV6_SADDR_RULE_SCOPE:
1515 			ret = score->scopedist;
1516 			break;
1517 		case IPV6_SADDR_RULE_PREFIX:
1518 			ret = score->matchlen;
1519 			break;
1520 		default:
1521 			ret = !!test_bit(i, score->scorebits);
1522 		}
1523 		goto out;
1524 	}
1525 
1526 	switch (i) {
1527 	case IPV6_SADDR_RULE_INIT:
1528 		/* Rule 0: remember if hiscore is not ready yet */
1529 		ret = !!score->ifa;
1530 		break;
1531 	case IPV6_SADDR_RULE_LOCAL:
1532 		/* Rule 1: Prefer same address */
1533 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1534 		break;
1535 	case IPV6_SADDR_RULE_SCOPE:
1536 		/* Rule 2: Prefer appropriate scope
1537 		 *
1538 		 *      ret
1539 		 *       ^
1540 		 *    -1 |  d 15
1541 		 *    ---+--+-+---> scope
1542 		 *       |
1543 		 *       |             d is scope of the destination.
1544 		 *  B-d  |  \
1545 		 *       |   \      <- smaller scope is better if
1546 		 *  B-15 |    \        if scope is enough for destination.
1547 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1548 		 * d-C-1 | /
1549 		 *       |/         <- greater is better
1550 		 *   -C  /             if scope is not enough for destination.
1551 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1552 		 *
1553 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1554 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1555 		 * Assume B = 0 and we get C > 29.
1556 		 */
1557 		ret = __ipv6_addr_src_scope(score->addr_type);
1558 		if (ret >= dst->scope)
1559 			ret = -ret;
1560 		else
1561 			ret -= 128;	/* 30 is enough */
1562 		score->scopedist = ret;
1563 		break;
1564 	case IPV6_SADDR_RULE_PREFERRED:
1565 	    {
1566 		/* Rule 3: Avoid deprecated and optimistic addresses */
1567 		u8 avoid = IFA_F_DEPRECATED;
1568 
1569 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1570 			avoid |= IFA_F_OPTIMISTIC;
1571 		ret = ipv6_saddr_preferred(score->addr_type) ||
1572 		      !(score->ifa->flags & avoid);
1573 		break;
1574 	    }
1575 #ifdef CONFIG_IPV6_MIP6
1576 	case IPV6_SADDR_RULE_HOA:
1577 	    {
1578 		/* Rule 4: Prefer home address */
1579 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1580 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1581 		break;
1582 	    }
1583 #endif
1584 	case IPV6_SADDR_RULE_OIF:
1585 		/* Rule 5: Prefer outgoing interface */
1586 		ret = (!dst->ifindex ||
1587 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1588 		break;
1589 	case IPV6_SADDR_RULE_LABEL:
1590 		/* Rule 6: Prefer matching label */
1591 		ret = ipv6_addr_label(net,
1592 				      &score->ifa->addr, score->addr_type,
1593 				      score->ifa->idev->dev->ifindex) == dst->label;
1594 		break;
1595 	case IPV6_SADDR_RULE_PRIVACY:
1596 	    {
1597 		/* Rule 7: Prefer public address
1598 		 * Note: prefer temporary address if use_tempaddr >= 2
1599 		 */
1600 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1601 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1602 				score->ifa->idev->cnf.use_tempaddr >= 2;
1603 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1604 		break;
1605 	    }
1606 	case IPV6_SADDR_RULE_ORCHID:
1607 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1608 		 *	    non-ORCHID vs non-ORCHID
1609 		 */
1610 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1611 			ipv6_addr_orchid(dst->addr));
1612 		break;
1613 	case IPV6_SADDR_RULE_PREFIX:
1614 		/* Rule 8: Use longest matching prefix */
1615 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1616 		if (ret > score->ifa->prefix_len)
1617 			ret = score->ifa->prefix_len;
1618 		score->matchlen = ret;
1619 		break;
1620 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1621 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1622 		/* Optimistic addresses still have lower precedence than other
1623 		 * preferred addresses.
1624 		 */
1625 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1626 		break;
1627 #endif
1628 	default:
1629 		ret = 0;
1630 	}
1631 
1632 	if (ret)
1633 		__set_bit(i, score->scorebits);
1634 	score->rule = i;
1635 out:
1636 	return ret;
1637 }
1638 
1639 static int __ipv6_dev_get_saddr(struct net *net,
1640 				struct ipv6_saddr_dst *dst,
1641 				struct inet6_dev *idev,
1642 				struct ipv6_saddr_score *scores,
1643 				int hiscore_idx)
1644 {
1645 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1646 
1647 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1648 		int i;
1649 
1650 		/*
1651 		 * - Tentative Address (RFC2462 section 5.4)
1652 		 *  - A tentative address is not considered
1653 		 *    "assigned to an interface" in the traditional
1654 		 *    sense, unless it is also flagged as optimistic.
1655 		 * - Candidate Source Address (section 4)
1656 		 *  - In any case, anycast addresses, multicast
1657 		 *    addresses, and the unspecified address MUST
1658 		 *    NOT be included in a candidate set.
1659 		 */
1660 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1661 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1662 			continue;
1663 
1664 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1665 
1666 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1667 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1668 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1669 					    idev->dev->name);
1670 			continue;
1671 		}
1672 
1673 		score->rule = -1;
1674 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1675 
1676 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1677 			int minihiscore, miniscore;
1678 
1679 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1680 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1681 
1682 			if (minihiscore > miniscore) {
1683 				if (i == IPV6_SADDR_RULE_SCOPE &&
1684 				    score->scopedist > 0) {
1685 					/*
1686 					 * special case:
1687 					 * each remaining entry
1688 					 * has too small (not enough)
1689 					 * scope, because ifa entries
1690 					 * are sorted by their scope
1691 					 * values.
1692 					 */
1693 					goto out;
1694 				}
1695 				break;
1696 			} else if (minihiscore < miniscore) {
1697 				swap(hiscore, score);
1698 				hiscore_idx = 1 - hiscore_idx;
1699 
1700 				/* restore our iterator */
1701 				score->ifa = hiscore->ifa;
1702 
1703 				break;
1704 			}
1705 		}
1706 	}
1707 out:
1708 	return hiscore_idx;
1709 }
1710 
1711 static int ipv6_get_saddr_master(struct net *net,
1712 				 const struct net_device *dst_dev,
1713 				 const struct net_device *master,
1714 				 struct ipv6_saddr_dst *dst,
1715 				 struct ipv6_saddr_score *scores,
1716 				 int hiscore_idx)
1717 {
1718 	struct inet6_dev *idev;
1719 
1720 	idev = __in6_dev_get(dst_dev);
1721 	if (idev)
1722 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1723 						   scores, hiscore_idx);
1724 
1725 	idev = __in6_dev_get(master);
1726 	if (idev)
1727 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1728 						   scores, hiscore_idx);
1729 
1730 	return hiscore_idx;
1731 }
1732 
1733 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1734 		       const struct in6_addr *daddr, unsigned int prefs,
1735 		       struct in6_addr *saddr)
1736 {
1737 	struct ipv6_saddr_score scores[2], *hiscore;
1738 	struct ipv6_saddr_dst dst;
1739 	struct inet6_dev *idev;
1740 	struct net_device *dev;
1741 	int dst_type;
1742 	bool use_oif_addr = false;
1743 	int hiscore_idx = 0;
1744 	int ret = 0;
1745 
1746 	dst_type = __ipv6_addr_type(daddr);
1747 	dst.addr = daddr;
1748 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1749 	dst.scope = __ipv6_addr_src_scope(dst_type);
1750 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1751 	dst.prefs = prefs;
1752 
1753 	scores[hiscore_idx].rule = -1;
1754 	scores[hiscore_idx].ifa = NULL;
1755 
1756 	rcu_read_lock();
1757 
1758 	/* Candidate Source Address (section 4)
1759 	 *  - multicast and link-local destination address,
1760 	 *    the set of candidate source address MUST only
1761 	 *    include addresses assigned to interfaces
1762 	 *    belonging to the same link as the outgoing
1763 	 *    interface.
1764 	 * (- For site-local destination addresses, the
1765 	 *    set of candidate source addresses MUST only
1766 	 *    include addresses assigned to interfaces
1767 	 *    belonging to the same site as the outgoing
1768 	 *    interface.)
1769 	 *  - "It is RECOMMENDED that the candidate source addresses
1770 	 *    be the set of unicast addresses assigned to the
1771 	 *    interface that will be used to send to the destination
1772 	 *    (the 'outgoing' interface)." (RFC 6724)
1773 	 */
1774 	if (dst_dev) {
1775 		idev = __in6_dev_get(dst_dev);
1776 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1777 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1778 		    (idev && idev->cnf.use_oif_addrs_only)) {
1779 			use_oif_addr = true;
1780 		}
1781 	}
1782 
1783 	if (use_oif_addr) {
1784 		if (idev)
1785 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1786 	} else {
1787 		const struct net_device *master;
1788 		int master_idx = 0;
1789 
1790 		/* if dst_dev exists and is enslaved to an L3 device, then
1791 		 * prefer addresses from dst_dev and then the master over
1792 		 * any other enslaved devices in the L3 domain.
1793 		 */
1794 		master = l3mdev_master_dev_rcu(dst_dev);
1795 		if (master) {
1796 			master_idx = master->ifindex;
1797 
1798 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1799 							    master, &dst,
1800 							    scores, hiscore_idx);
1801 
1802 			if (scores[hiscore_idx].ifa)
1803 				goto out;
1804 		}
1805 
1806 		for_each_netdev_rcu(net, dev) {
1807 			/* only consider addresses on devices in the
1808 			 * same L3 domain
1809 			 */
1810 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1811 				continue;
1812 			idev = __in6_dev_get(dev);
1813 			if (!idev)
1814 				continue;
1815 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1816 		}
1817 	}
1818 
1819 out:
1820 	hiscore = &scores[hiscore_idx];
1821 	if (!hiscore->ifa)
1822 		ret = -EADDRNOTAVAIL;
1823 	else
1824 		*saddr = hiscore->ifa->addr;
1825 
1826 	rcu_read_unlock();
1827 	return ret;
1828 }
1829 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1830 
1831 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1832 		      u32 banned_flags)
1833 {
1834 	struct inet6_ifaddr *ifp;
1835 	int err = -EADDRNOTAVAIL;
1836 
1837 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1838 		if (ifp->scope > IFA_LINK)
1839 			break;
1840 		if (ifp->scope == IFA_LINK &&
1841 		    !(ifp->flags & banned_flags)) {
1842 			*addr = ifp->addr;
1843 			err = 0;
1844 			break;
1845 		}
1846 	}
1847 	return err;
1848 }
1849 
1850 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1851 		    u32 banned_flags)
1852 {
1853 	struct inet6_dev *idev;
1854 	int err = -EADDRNOTAVAIL;
1855 
1856 	rcu_read_lock();
1857 	idev = __in6_dev_get(dev);
1858 	if (idev) {
1859 		read_lock_bh(&idev->lock);
1860 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1861 		read_unlock_bh(&idev->lock);
1862 	}
1863 	rcu_read_unlock();
1864 	return err;
1865 }
1866 
1867 static int ipv6_count_addresses(const struct inet6_dev *idev)
1868 {
1869 	const struct inet6_ifaddr *ifp;
1870 	int cnt = 0;
1871 
1872 	rcu_read_lock();
1873 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1874 		cnt++;
1875 	rcu_read_unlock();
1876 	return cnt;
1877 }
1878 
1879 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1880 		  const struct net_device *dev, int strict)
1881 {
1882 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1883 				       strict, IFA_F_TENTATIVE);
1884 }
1885 EXPORT_SYMBOL(ipv6_chk_addr);
1886 
1887 /* device argument is used to find the L3 domain of interest. If
1888  * skip_dev_check is set, then the ifp device is not checked against
1889  * the passed in dev argument. So the 2 cases for addresses checks are:
1890  *   1. does the address exist in the L3 domain that dev is part of
1891  *      (skip_dev_check = true), or
1892  *
1893  *   2. does the address exist on the specific device
1894  *      (skip_dev_check = false)
1895  */
1896 static struct net_device *
1897 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1898 			  const struct net_device *dev, bool skip_dev_check,
1899 			  int strict, u32 banned_flags)
1900 {
1901 	unsigned int hash = inet6_addr_hash(net, addr);
1902 	struct net_device *l3mdev, *ndev;
1903 	struct inet6_ifaddr *ifp;
1904 	u32 ifp_flags;
1905 
1906 	rcu_read_lock();
1907 
1908 	l3mdev = l3mdev_master_dev_rcu(dev);
1909 	if (skip_dev_check)
1910 		dev = NULL;
1911 
1912 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1913 		ndev = ifp->idev->dev;
1914 		if (!net_eq(dev_net(ndev), net))
1915 			continue;
1916 
1917 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1918 			continue;
1919 
1920 		/* Decouple optimistic from tentative for evaluation here.
1921 		 * Ban optimistic addresses explicitly, when required.
1922 		 */
1923 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1924 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1925 			    : ifp->flags;
1926 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1927 		    !(ifp_flags&banned_flags) &&
1928 		    (!dev || ndev == dev ||
1929 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1930 			rcu_read_unlock();
1931 			return ndev;
1932 		}
1933 	}
1934 
1935 	rcu_read_unlock();
1936 	return NULL;
1937 }
1938 
1939 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1940 			    const struct net_device *dev, bool skip_dev_check,
1941 			    int strict, u32 banned_flags)
1942 {
1943 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1944 					 strict, banned_flags) ? 1 : 0;
1945 }
1946 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1947 
1948 
1949 /* Compares an address/prefix_len with addresses on device @dev.
1950  * If one is found it returns true.
1951  */
1952 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1953 	const unsigned int prefix_len, struct net_device *dev)
1954 {
1955 	const struct inet6_ifaddr *ifa;
1956 	const struct inet6_dev *idev;
1957 	bool ret = false;
1958 
1959 	rcu_read_lock();
1960 	idev = __in6_dev_get(dev);
1961 	if (idev) {
1962 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1963 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1964 			if (ret)
1965 				break;
1966 		}
1967 	}
1968 	rcu_read_unlock();
1969 
1970 	return ret;
1971 }
1972 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1973 
1974 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1975 {
1976 	const struct inet6_ifaddr *ifa;
1977 	const struct inet6_dev *idev;
1978 	int	onlink;
1979 
1980 	onlink = 0;
1981 	rcu_read_lock();
1982 	idev = __in6_dev_get(dev);
1983 	if (idev) {
1984 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1985 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1986 						   ifa->prefix_len);
1987 			if (onlink)
1988 				break;
1989 		}
1990 	}
1991 	rcu_read_unlock();
1992 	return onlink;
1993 }
1994 EXPORT_SYMBOL(ipv6_chk_prefix);
1995 
1996 /**
1997  * ipv6_dev_find - find the first device with a given source address.
1998  * @net: the net namespace
1999  * @addr: the source address
2000  *
2001  * The caller should be protected by RCU, or RTNL.
2002  */
2003 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2004 				 struct net_device *dev)
2005 {
2006 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2007 					 IFA_F_TENTATIVE);
2008 }
2009 EXPORT_SYMBOL(ipv6_dev_find);
2010 
2011 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2012 				     struct net_device *dev, int strict)
2013 {
2014 	unsigned int hash = inet6_addr_hash(net, addr);
2015 	struct inet6_ifaddr *ifp, *result = NULL;
2016 
2017 	rcu_read_lock();
2018 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2019 		if (!net_eq(dev_net(ifp->idev->dev), net))
2020 			continue;
2021 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2022 			if (!dev || ifp->idev->dev == dev ||
2023 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2024 				result = ifp;
2025 				in6_ifa_hold(ifp);
2026 				break;
2027 			}
2028 		}
2029 	}
2030 	rcu_read_unlock();
2031 
2032 	return result;
2033 }
2034 
2035 /* Gets referenced address, destroys ifaddr */
2036 
2037 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2038 {
2039 	if (dad_failed)
2040 		ifp->flags |= IFA_F_DADFAILED;
2041 
2042 	if (ifp->flags&IFA_F_TEMPORARY) {
2043 		struct inet6_ifaddr *ifpub;
2044 		spin_lock_bh(&ifp->lock);
2045 		ifpub = ifp->ifpub;
2046 		if (ifpub) {
2047 			in6_ifa_hold(ifpub);
2048 			spin_unlock_bh(&ifp->lock);
2049 			ipv6_create_tempaddr(ifpub, true);
2050 			in6_ifa_put(ifpub);
2051 		} else {
2052 			spin_unlock_bh(&ifp->lock);
2053 		}
2054 		ipv6_del_addr(ifp);
2055 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2056 		spin_lock_bh(&ifp->lock);
2057 		addrconf_del_dad_work(ifp);
2058 		ifp->flags |= IFA_F_TENTATIVE;
2059 		if (dad_failed)
2060 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2061 		spin_unlock_bh(&ifp->lock);
2062 		if (dad_failed)
2063 			ipv6_ifa_notify(0, ifp);
2064 		in6_ifa_put(ifp);
2065 	} else {
2066 		ipv6_del_addr(ifp);
2067 	}
2068 }
2069 
2070 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2071 {
2072 	int err = -ENOENT;
2073 
2074 	spin_lock_bh(&ifp->lock);
2075 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2076 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2077 		err = 0;
2078 	}
2079 	spin_unlock_bh(&ifp->lock);
2080 
2081 	return err;
2082 }
2083 
2084 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2085 {
2086 	struct inet6_dev *idev = ifp->idev;
2087 	struct net *net = dev_net(ifp->idev->dev);
2088 
2089 	if (addrconf_dad_end(ifp)) {
2090 		in6_ifa_put(ifp);
2091 		return;
2092 	}
2093 
2094 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2095 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2096 
2097 	spin_lock_bh(&ifp->lock);
2098 
2099 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2100 		struct in6_addr new_addr;
2101 		struct inet6_ifaddr *ifp2;
2102 		int retries = ifp->stable_privacy_retry + 1;
2103 		struct ifa6_config cfg = {
2104 			.pfx = &new_addr,
2105 			.plen = ifp->prefix_len,
2106 			.ifa_flags = ifp->flags,
2107 			.valid_lft = ifp->valid_lft,
2108 			.preferred_lft = ifp->prefered_lft,
2109 			.scope = ifp->scope,
2110 		};
2111 
2112 		if (retries > net->ipv6.sysctl.idgen_retries) {
2113 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2114 					     ifp->idev->dev->name);
2115 			goto errdad;
2116 		}
2117 
2118 		new_addr = ifp->addr;
2119 		if (ipv6_generate_stable_address(&new_addr, retries,
2120 						 idev))
2121 			goto errdad;
2122 
2123 		spin_unlock_bh(&ifp->lock);
2124 
2125 		if (idev->cnf.max_addresses &&
2126 		    ipv6_count_addresses(idev) >=
2127 		    idev->cnf.max_addresses)
2128 			goto lock_errdad;
2129 
2130 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2131 				     ifp->idev->dev->name);
2132 
2133 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2134 		if (IS_ERR(ifp2))
2135 			goto lock_errdad;
2136 
2137 		spin_lock_bh(&ifp2->lock);
2138 		ifp2->stable_privacy_retry = retries;
2139 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2140 		spin_unlock_bh(&ifp2->lock);
2141 
2142 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2143 		in6_ifa_put(ifp2);
2144 lock_errdad:
2145 		spin_lock_bh(&ifp->lock);
2146 	}
2147 
2148 errdad:
2149 	/* transition from _POSTDAD to _ERRDAD */
2150 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2151 	spin_unlock_bh(&ifp->lock);
2152 
2153 	addrconf_mod_dad_work(ifp, 0);
2154 	in6_ifa_put(ifp);
2155 }
2156 
2157 /* Join to solicited addr multicast group.
2158  * caller must hold RTNL */
2159 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2160 {
2161 	struct in6_addr maddr;
2162 
2163 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2164 		return;
2165 
2166 	addrconf_addr_solict_mult(addr, &maddr);
2167 	ipv6_dev_mc_inc(dev, &maddr);
2168 }
2169 
2170 /* caller must hold RTNL */
2171 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2172 {
2173 	struct in6_addr maddr;
2174 
2175 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2176 		return;
2177 
2178 	addrconf_addr_solict_mult(addr, &maddr);
2179 	__ipv6_dev_mc_dec(idev, &maddr);
2180 }
2181 
2182 /* caller must hold RTNL */
2183 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2184 {
2185 	struct in6_addr addr;
2186 
2187 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2188 		return;
2189 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2190 	if (ipv6_addr_any(&addr))
2191 		return;
2192 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2193 }
2194 
2195 /* caller must hold RTNL */
2196 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2197 {
2198 	struct in6_addr addr;
2199 
2200 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2201 		return;
2202 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2203 	if (ipv6_addr_any(&addr))
2204 		return;
2205 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2206 }
2207 
2208 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2209 {
2210 	switch (dev->addr_len) {
2211 	case ETH_ALEN:
2212 		memcpy(eui, dev->dev_addr, 3);
2213 		eui[3] = 0xFF;
2214 		eui[4] = 0xFE;
2215 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2216 		break;
2217 	case EUI64_ADDR_LEN:
2218 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2219 		eui[0] ^= 2;
2220 		break;
2221 	default:
2222 		return -1;
2223 	}
2224 
2225 	return 0;
2226 }
2227 
2228 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2229 {
2230 	union fwnet_hwaddr *ha;
2231 
2232 	if (dev->addr_len != FWNET_ALEN)
2233 		return -1;
2234 
2235 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2236 
2237 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2238 	eui[0] ^= 2;
2239 	return 0;
2240 }
2241 
2242 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2243 {
2244 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2245 	if (dev->addr_len != ARCNET_ALEN)
2246 		return -1;
2247 	memset(eui, 0, 7);
2248 	eui[7] = *(u8 *)dev->dev_addr;
2249 	return 0;
2250 }
2251 
2252 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2253 {
2254 	if (dev->addr_len != INFINIBAND_ALEN)
2255 		return -1;
2256 	memcpy(eui, dev->dev_addr + 12, 8);
2257 	eui[0] |= 2;
2258 	return 0;
2259 }
2260 
2261 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2262 {
2263 	if (addr == 0)
2264 		return -1;
2265 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2266 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2267 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2268 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2269 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2270 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2271 	eui[1] = 0;
2272 	eui[2] = 0x5E;
2273 	eui[3] = 0xFE;
2274 	memcpy(eui + 4, &addr, 4);
2275 	return 0;
2276 }
2277 
2278 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2279 {
2280 	if (dev->priv_flags & IFF_ISATAP)
2281 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2282 	return -1;
2283 }
2284 
2285 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2286 {
2287 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2288 }
2289 
2290 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2291 {
2292 	memcpy(eui, dev->perm_addr, 3);
2293 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2294 	eui[3] = 0xFF;
2295 	eui[4] = 0xFE;
2296 	eui[0] ^= 2;
2297 	return 0;
2298 }
2299 
2300 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2301 {
2302 	switch (dev->type) {
2303 	case ARPHRD_ETHER:
2304 	case ARPHRD_FDDI:
2305 		return addrconf_ifid_eui48(eui, dev);
2306 	case ARPHRD_ARCNET:
2307 		return addrconf_ifid_arcnet(eui, dev);
2308 	case ARPHRD_INFINIBAND:
2309 		return addrconf_ifid_infiniband(eui, dev);
2310 	case ARPHRD_SIT:
2311 		return addrconf_ifid_sit(eui, dev);
2312 	case ARPHRD_IPGRE:
2313 	case ARPHRD_TUNNEL:
2314 		return addrconf_ifid_gre(eui, dev);
2315 	case ARPHRD_6LOWPAN:
2316 		return addrconf_ifid_6lowpan(eui, dev);
2317 	case ARPHRD_IEEE1394:
2318 		return addrconf_ifid_ieee1394(eui, dev);
2319 	case ARPHRD_TUNNEL6:
2320 	case ARPHRD_IP6GRE:
2321 	case ARPHRD_RAWIP:
2322 		return addrconf_ifid_ip6tnl(eui, dev);
2323 	}
2324 	return -1;
2325 }
2326 
2327 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2328 {
2329 	int err = -1;
2330 	struct inet6_ifaddr *ifp;
2331 
2332 	read_lock_bh(&idev->lock);
2333 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2334 		if (ifp->scope > IFA_LINK)
2335 			break;
2336 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2337 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2338 			err = 0;
2339 			break;
2340 		}
2341 	}
2342 	read_unlock_bh(&idev->lock);
2343 	return err;
2344 }
2345 
2346 /* Generation of a randomized Interface Identifier
2347  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2348  */
2349 
2350 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2351 {
2352 regen:
2353 	get_random_bytes(&addr->s6_addr[8], 8);
2354 
2355 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2356 	 * check if generated address is not inappropriate:
2357 	 *
2358 	 * - Reserved IPv6 Interface Identifers
2359 	 * - XXX: already assigned to an address on the device
2360 	 */
2361 
2362 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2363 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2364 		goto regen;
2365 
2366 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2367 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2368 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2369 	 */
2370 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2371 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2372 		goto regen;
2373 
2374 	/* Reserved subnet anycast addresses */
2375 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2376 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2377 		goto regen;
2378 }
2379 
2380 /*
2381  *	Add prefix route.
2382  */
2383 
2384 static void
2385 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2386 		      struct net_device *dev, unsigned long expires,
2387 		      u32 flags, gfp_t gfp_flags)
2388 {
2389 	struct fib6_config cfg = {
2390 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2391 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2392 		.fc_ifindex = dev->ifindex,
2393 		.fc_expires = expires,
2394 		.fc_dst_len = plen,
2395 		.fc_flags = RTF_UP | flags,
2396 		.fc_nlinfo.nl_net = dev_net(dev),
2397 		.fc_protocol = RTPROT_KERNEL,
2398 		.fc_type = RTN_UNICAST,
2399 	};
2400 
2401 	cfg.fc_dst = *pfx;
2402 
2403 	/* Prevent useless cloning on PtP SIT.
2404 	   This thing is done here expecting that the whole
2405 	   class of non-broadcast devices need not cloning.
2406 	 */
2407 #if IS_ENABLED(CONFIG_IPV6_SIT)
2408 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2409 		cfg.fc_flags |= RTF_NONEXTHOP;
2410 #endif
2411 
2412 	ip6_route_add(&cfg, gfp_flags, NULL);
2413 }
2414 
2415 
2416 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2417 						  int plen,
2418 						  const struct net_device *dev,
2419 						  u32 flags, u32 noflags,
2420 						  bool no_gw)
2421 {
2422 	struct fib6_node *fn;
2423 	struct fib6_info *rt = NULL;
2424 	struct fib6_table *table;
2425 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2426 
2427 	table = fib6_get_table(dev_net(dev), tb_id);
2428 	if (!table)
2429 		return NULL;
2430 
2431 	rcu_read_lock();
2432 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2433 	if (!fn)
2434 		goto out;
2435 
2436 	for_each_fib6_node_rt_rcu(fn) {
2437 		/* prefix routes only use builtin fib6_nh */
2438 		if (rt->nh)
2439 			continue;
2440 
2441 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2442 			continue;
2443 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2444 			continue;
2445 		if ((rt->fib6_flags & flags) != flags)
2446 			continue;
2447 		if ((rt->fib6_flags & noflags) != 0)
2448 			continue;
2449 		if (!fib6_info_hold_safe(rt))
2450 			continue;
2451 		break;
2452 	}
2453 out:
2454 	rcu_read_unlock();
2455 	return rt;
2456 }
2457 
2458 
2459 /* Create "default" multicast route to the interface */
2460 
2461 static void addrconf_add_mroute(struct net_device *dev)
2462 {
2463 	struct fib6_config cfg = {
2464 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2465 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2466 		.fc_ifindex = dev->ifindex,
2467 		.fc_dst_len = 8,
2468 		.fc_flags = RTF_UP,
2469 		.fc_type = RTN_UNICAST,
2470 		.fc_nlinfo.nl_net = dev_net(dev),
2471 	};
2472 
2473 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2474 
2475 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2476 }
2477 
2478 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2479 {
2480 	struct inet6_dev *idev;
2481 
2482 	ASSERT_RTNL();
2483 
2484 	idev = ipv6_find_idev(dev);
2485 	if (IS_ERR(idev))
2486 		return idev;
2487 
2488 	if (idev->cnf.disable_ipv6)
2489 		return ERR_PTR(-EACCES);
2490 
2491 	/* Add default multicast route */
2492 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2493 		addrconf_add_mroute(dev);
2494 
2495 	return idev;
2496 }
2497 
2498 static void manage_tempaddrs(struct inet6_dev *idev,
2499 			     struct inet6_ifaddr *ifp,
2500 			     __u32 valid_lft, __u32 prefered_lft,
2501 			     bool create, unsigned long now)
2502 {
2503 	u32 flags;
2504 	struct inet6_ifaddr *ift;
2505 
2506 	read_lock_bh(&idev->lock);
2507 	/* update all temporary addresses in the list */
2508 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2509 		int age, max_valid, max_prefered;
2510 
2511 		if (ifp != ift->ifpub)
2512 			continue;
2513 
2514 		/* RFC 4941 section 3.3:
2515 		 * If a received option will extend the lifetime of a public
2516 		 * address, the lifetimes of temporary addresses should
2517 		 * be extended, subject to the overall constraint that no
2518 		 * temporary addresses should ever remain "valid" or "preferred"
2519 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2520 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2521 		 */
2522 		age = (now - ift->cstamp) / HZ;
2523 		max_valid = idev->cnf.temp_valid_lft - age;
2524 		if (max_valid < 0)
2525 			max_valid = 0;
2526 
2527 		max_prefered = idev->cnf.temp_prefered_lft -
2528 			       idev->desync_factor - age;
2529 		if (max_prefered < 0)
2530 			max_prefered = 0;
2531 
2532 		if (valid_lft > max_valid)
2533 			valid_lft = max_valid;
2534 
2535 		if (prefered_lft > max_prefered)
2536 			prefered_lft = max_prefered;
2537 
2538 		spin_lock(&ift->lock);
2539 		flags = ift->flags;
2540 		ift->valid_lft = valid_lft;
2541 		ift->prefered_lft = prefered_lft;
2542 		ift->tstamp = now;
2543 		if (prefered_lft > 0)
2544 			ift->flags &= ~IFA_F_DEPRECATED;
2545 
2546 		spin_unlock(&ift->lock);
2547 		if (!(flags&IFA_F_TENTATIVE))
2548 			ipv6_ifa_notify(0, ift);
2549 	}
2550 
2551 	if ((create || list_empty(&idev->tempaddr_list)) &&
2552 	    idev->cnf.use_tempaddr > 0) {
2553 		/* When a new public address is created as described
2554 		 * in [ADDRCONF], also create a new temporary address.
2555 		 * Also create a temporary address if it's enabled but
2556 		 * no temporary address currently exists.
2557 		 */
2558 		read_unlock_bh(&idev->lock);
2559 		ipv6_create_tempaddr(ifp, false);
2560 	} else {
2561 		read_unlock_bh(&idev->lock);
2562 	}
2563 }
2564 
2565 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2566 {
2567 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2568 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2569 }
2570 
2571 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2572 				 const struct prefix_info *pinfo,
2573 				 struct inet6_dev *in6_dev,
2574 				 const struct in6_addr *addr, int addr_type,
2575 				 u32 addr_flags, bool sllao, bool tokenized,
2576 				 __u32 valid_lft, u32 prefered_lft)
2577 {
2578 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2579 	int create = 0;
2580 
2581 	if (!ifp && valid_lft) {
2582 		int max_addresses = in6_dev->cnf.max_addresses;
2583 		struct ifa6_config cfg = {
2584 			.pfx = addr,
2585 			.plen = pinfo->prefix_len,
2586 			.ifa_flags = addr_flags,
2587 			.valid_lft = valid_lft,
2588 			.preferred_lft = prefered_lft,
2589 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2590 		};
2591 
2592 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2593 		if ((net->ipv6.devconf_all->optimistic_dad ||
2594 		     in6_dev->cnf.optimistic_dad) &&
2595 		    !net->ipv6.devconf_all->forwarding && sllao)
2596 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2597 #endif
2598 
2599 		/* Do not allow to create too much of autoconfigured
2600 		 * addresses; this would be too easy way to crash kernel.
2601 		 */
2602 		if (!max_addresses ||
2603 		    ipv6_count_addresses(in6_dev) < max_addresses)
2604 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2605 
2606 		if (IS_ERR_OR_NULL(ifp))
2607 			return -1;
2608 
2609 		create = 1;
2610 		spin_lock_bh(&ifp->lock);
2611 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2612 		ifp->cstamp = jiffies;
2613 		ifp->tokenized = tokenized;
2614 		spin_unlock_bh(&ifp->lock);
2615 		addrconf_dad_start(ifp);
2616 	}
2617 
2618 	if (ifp) {
2619 		u32 flags;
2620 		unsigned long now;
2621 		u32 stored_lft;
2622 
2623 		/* Update lifetime (RFC4862 5.5.3 e)
2624 		 * We deviate from RFC4862 by honoring all Valid Lifetimes to
2625 		 * improve the reaction of SLAAC to renumbering events
2626 		 * (draft-gont-6man-slaac-renum-06, Section 4.2)
2627 		 */
2628 		spin_lock_bh(&ifp->lock);
2629 		now = jiffies;
2630 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2631 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2632 		else
2633 			stored_lft = 0;
2634 
2635 		if (!create && stored_lft) {
2636 			ifp->valid_lft = valid_lft;
2637 			ifp->prefered_lft = prefered_lft;
2638 			ifp->tstamp = now;
2639 			flags = ifp->flags;
2640 			ifp->flags &= ~IFA_F_DEPRECATED;
2641 			spin_unlock_bh(&ifp->lock);
2642 
2643 			if (!(flags&IFA_F_TENTATIVE))
2644 				ipv6_ifa_notify(0, ifp);
2645 		} else
2646 			spin_unlock_bh(&ifp->lock);
2647 
2648 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2649 				 create, now);
2650 
2651 		in6_ifa_put(ifp);
2652 		addrconf_verify();
2653 	}
2654 
2655 	return 0;
2656 }
2657 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2658 
2659 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2660 {
2661 	struct prefix_info *pinfo;
2662 	__u32 valid_lft;
2663 	__u32 prefered_lft;
2664 	int addr_type, err;
2665 	u32 addr_flags = 0;
2666 	struct inet6_dev *in6_dev;
2667 	struct net *net = dev_net(dev);
2668 
2669 	pinfo = (struct prefix_info *) opt;
2670 
2671 	if (len < sizeof(struct prefix_info)) {
2672 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2673 		return;
2674 	}
2675 
2676 	/*
2677 	 *	Validation checks ([ADDRCONF], page 19)
2678 	 */
2679 
2680 	addr_type = ipv6_addr_type(&pinfo->prefix);
2681 
2682 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2683 		return;
2684 
2685 	valid_lft = ntohl(pinfo->valid);
2686 	prefered_lft = ntohl(pinfo->prefered);
2687 
2688 	if (prefered_lft > valid_lft) {
2689 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2690 		return;
2691 	}
2692 
2693 	in6_dev = in6_dev_get(dev);
2694 
2695 	if (!in6_dev) {
2696 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2697 				    dev->name);
2698 		return;
2699 	}
2700 
2701 	/*
2702 	 *	Two things going on here:
2703 	 *	1) Add routes for on-link prefixes
2704 	 *	2) Configure prefixes with the auto flag set
2705 	 */
2706 
2707 	if (pinfo->onlink) {
2708 		struct fib6_info *rt;
2709 		unsigned long rt_expires;
2710 
2711 		/* Avoid arithmetic overflow. Really, we could
2712 		 * save rt_expires in seconds, likely valid_lft,
2713 		 * but it would require division in fib gc, that it
2714 		 * not good.
2715 		 */
2716 		if (HZ > USER_HZ)
2717 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2718 		else
2719 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2720 
2721 		if (addrconf_finite_timeout(rt_expires))
2722 			rt_expires *= HZ;
2723 
2724 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2725 					       pinfo->prefix_len,
2726 					       dev,
2727 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2728 					       RTF_DEFAULT, true);
2729 
2730 		if (rt) {
2731 			/* Autoconf prefix route */
2732 			if (valid_lft == 0) {
2733 				ip6_del_rt(net, rt, false);
2734 				rt = NULL;
2735 			} else if (addrconf_finite_timeout(rt_expires)) {
2736 				/* not infinity */
2737 				fib6_set_expires(rt, jiffies + rt_expires);
2738 			} else {
2739 				fib6_clean_expires(rt);
2740 			}
2741 		} else if (valid_lft) {
2742 			clock_t expires = 0;
2743 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2744 			if (addrconf_finite_timeout(rt_expires)) {
2745 				/* not infinity */
2746 				flags |= RTF_EXPIRES;
2747 				expires = jiffies_to_clock_t(rt_expires);
2748 			}
2749 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2750 					      0, dev, expires, flags,
2751 					      GFP_ATOMIC);
2752 		}
2753 		fib6_info_release(rt);
2754 	}
2755 
2756 	/* Try to figure out our local address for this prefix */
2757 
2758 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2759 		struct in6_addr addr;
2760 		bool tokenized = false, dev_addr_generated = false;
2761 
2762 		if (pinfo->prefix_len == 64) {
2763 			memcpy(&addr, &pinfo->prefix, 8);
2764 
2765 			if (!ipv6_addr_any(&in6_dev->token)) {
2766 				read_lock_bh(&in6_dev->lock);
2767 				memcpy(addr.s6_addr + 8,
2768 				       in6_dev->token.s6_addr + 8, 8);
2769 				read_unlock_bh(&in6_dev->lock);
2770 				tokenized = true;
2771 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2772 				   !ipv6_generate_stable_address(&addr, 0,
2773 								 in6_dev)) {
2774 				addr_flags |= IFA_F_STABLE_PRIVACY;
2775 				goto ok;
2776 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2777 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2778 				goto put;
2779 			} else {
2780 				dev_addr_generated = true;
2781 			}
2782 			goto ok;
2783 		}
2784 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2785 				    pinfo->prefix_len);
2786 		goto put;
2787 
2788 ok:
2789 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2790 						   &addr, addr_type,
2791 						   addr_flags, sllao,
2792 						   tokenized, valid_lft,
2793 						   prefered_lft);
2794 		if (err)
2795 			goto put;
2796 
2797 		/* Ignore error case here because previous prefix add addr was
2798 		 * successful which will be notified.
2799 		 */
2800 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2801 					      addr_type, addr_flags, sllao,
2802 					      tokenized, valid_lft,
2803 					      prefered_lft,
2804 					      dev_addr_generated);
2805 	}
2806 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2807 put:
2808 	in6_dev_put(in6_dev);
2809 }
2810 
2811 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2812 		struct in6_ifreq *ireq)
2813 {
2814 	struct ip_tunnel_parm p = { };
2815 	int err;
2816 
2817 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2818 		return -EADDRNOTAVAIL;
2819 
2820 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2821 	p.iph.version = 4;
2822 	p.iph.ihl = 5;
2823 	p.iph.protocol = IPPROTO_IPV6;
2824 	p.iph.ttl = 64;
2825 
2826 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2827 		return -EOPNOTSUPP;
2828 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2829 	if (err)
2830 		return err;
2831 
2832 	dev = __dev_get_by_name(net, p.name);
2833 	if (!dev)
2834 		return -ENOBUFS;
2835 	return dev_open(dev, NULL);
2836 }
2837 
2838 /*
2839  *	Set destination address.
2840  *	Special case for SIT interfaces where we create a new "virtual"
2841  *	device.
2842  */
2843 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2844 {
2845 	struct net_device *dev;
2846 	struct in6_ifreq ireq;
2847 	int err = -ENODEV;
2848 
2849 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2850 		return -ENODEV;
2851 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2852 		return -EFAULT;
2853 
2854 	rtnl_lock();
2855 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2856 	if (dev && dev->type == ARPHRD_SIT)
2857 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2858 	rtnl_unlock();
2859 	return err;
2860 }
2861 
2862 static int ipv6_mc_config(struct sock *sk, bool join,
2863 			  const struct in6_addr *addr, int ifindex)
2864 {
2865 	int ret;
2866 
2867 	ASSERT_RTNL();
2868 
2869 	lock_sock(sk);
2870 	if (join)
2871 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2872 	else
2873 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2874 	release_sock(sk);
2875 
2876 	return ret;
2877 }
2878 
2879 /*
2880  *	Manual configuration of address on an interface
2881  */
2882 static int inet6_addr_add(struct net *net, int ifindex,
2883 			  struct ifa6_config *cfg,
2884 			  struct netlink_ext_ack *extack)
2885 {
2886 	struct inet6_ifaddr *ifp;
2887 	struct inet6_dev *idev;
2888 	struct net_device *dev;
2889 	unsigned long timeout;
2890 	clock_t expires;
2891 	u32 flags;
2892 
2893 	ASSERT_RTNL();
2894 
2895 	if (cfg->plen > 128)
2896 		return -EINVAL;
2897 
2898 	/* check the lifetime */
2899 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2900 		return -EINVAL;
2901 
2902 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2903 		return -EINVAL;
2904 
2905 	dev = __dev_get_by_index(net, ifindex);
2906 	if (!dev)
2907 		return -ENODEV;
2908 
2909 	idev = addrconf_add_dev(dev);
2910 	if (IS_ERR(idev))
2911 		return PTR_ERR(idev);
2912 
2913 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2914 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2915 					 true, cfg->pfx, ifindex);
2916 
2917 		if (ret < 0)
2918 			return ret;
2919 	}
2920 
2921 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2922 
2923 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2924 	if (addrconf_finite_timeout(timeout)) {
2925 		expires = jiffies_to_clock_t(timeout * HZ);
2926 		cfg->valid_lft = timeout;
2927 		flags = RTF_EXPIRES;
2928 	} else {
2929 		expires = 0;
2930 		flags = 0;
2931 		cfg->ifa_flags |= IFA_F_PERMANENT;
2932 	}
2933 
2934 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2935 	if (addrconf_finite_timeout(timeout)) {
2936 		if (timeout == 0)
2937 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2938 		cfg->preferred_lft = timeout;
2939 	}
2940 
2941 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2942 	if (!IS_ERR(ifp)) {
2943 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2944 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2945 					      ifp->rt_priority, dev, expires,
2946 					      flags, GFP_KERNEL);
2947 		}
2948 
2949 		/* Send a netlink notification if DAD is enabled and
2950 		 * optimistic flag is not set
2951 		 */
2952 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2953 			ipv6_ifa_notify(0, ifp);
2954 		/*
2955 		 * Note that section 3.1 of RFC 4429 indicates
2956 		 * that the Optimistic flag should not be set for
2957 		 * manually configured addresses
2958 		 */
2959 		addrconf_dad_start(ifp);
2960 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2961 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2962 					 cfg->preferred_lft, true, jiffies);
2963 		in6_ifa_put(ifp);
2964 		addrconf_verify_rtnl();
2965 		return 0;
2966 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2967 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2968 			       cfg->pfx, ifindex);
2969 	}
2970 
2971 	return PTR_ERR(ifp);
2972 }
2973 
2974 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2975 			  const struct in6_addr *pfx, unsigned int plen)
2976 {
2977 	struct inet6_ifaddr *ifp;
2978 	struct inet6_dev *idev;
2979 	struct net_device *dev;
2980 
2981 	if (plen > 128)
2982 		return -EINVAL;
2983 
2984 	dev = __dev_get_by_index(net, ifindex);
2985 	if (!dev)
2986 		return -ENODEV;
2987 
2988 	idev = __in6_dev_get(dev);
2989 	if (!idev)
2990 		return -ENXIO;
2991 
2992 	read_lock_bh(&idev->lock);
2993 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2994 		if (ifp->prefix_len == plen &&
2995 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2996 			in6_ifa_hold(ifp);
2997 			read_unlock_bh(&idev->lock);
2998 
2999 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3000 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3001 				manage_tempaddrs(idev, ifp, 0, 0, false,
3002 						 jiffies);
3003 			ipv6_del_addr(ifp);
3004 			addrconf_verify_rtnl();
3005 			if (ipv6_addr_is_multicast(pfx)) {
3006 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3007 					       false, pfx, dev->ifindex);
3008 			}
3009 			return 0;
3010 		}
3011 	}
3012 	read_unlock_bh(&idev->lock);
3013 	return -EADDRNOTAVAIL;
3014 }
3015 
3016 
3017 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3018 {
3019 	struct ifa6_config cfg = {
3020 		.ifa_flags = IFA_F_PERMANENT,
3021 		.preferred_lft = INFINITY_LIFE_TIME,
3022 		.valid_lft = INFINITY_LIFE_TIME,
3023 	};
3024 	struct in6_ifreq ireq;
3025 	int err;
3026 
3027 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3028 		return -EPERM;
3029 
3030 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3031 		return -EFAULT;
3032 
3033 	cfg.pfx = &ireq.ifr6_addr;
3034 	cfg.plen = ireq.ifr6_prefixlen;
3035 
3036 	rtnl_lock();
3037 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3038 	rtnl_unlock();
3039 	return err;
3040 }
3041 
3042 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3043 {
3044 	struct in6_ifreq ireq;
3045 	int err;
3046 
3047 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3048 		return -EPERM;
3049 
3050 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3051 		return -EFAULT;
3052 
3053 	rtnl_lock();
3054 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3055 			     ireq.ifr6_prefixlen);
3056 	rtnl_unlock();
3057 	return err;
3058 }
3059 
3060 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3061 		     int plen, int scope)
3062 {
3063 	struct inet6_ifaddr *ifp;
3064 	struct ifa6_config cfg = {
3065 		.pfx = addr,
3066 		.plen = plen,
3067 		.ifa_flags = IFA_F_PERMANENT,
3068 		.valid_lft = INFINITY_LIFE_TIME,
3069 		.preferred_lft = INFINITY_LIFE_TIME,
3070 		.scope = scope
3071 	};
3072 
3073 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3074 	if (!IS_ERR(ifp)) {
3075 		spin_lock_bh(&ifp->lock);
3076 		ifp->flags &= ~IFA_F_TENTATIVE;
3077 		spin_unlock_bh(&ifp->lock);
3078 		rt_genid_bump_ipv6(dev_net(idev->dev));
3079 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3080 		in6_ifa_put(ifp);
3081 	}
3082 }
3083 
3084 #if IS_ENABLED(CONFIG_IPV6_SIT)
3085 static void sit_add_v4_addrs(struct inet6_dev *idev)
3086 {
3087 	struct in6_addr addr;
3088 	struct net_device *dev;
3089 	struct net *net = dev_net(idev->dev);
3090 	int scope, plen;
3091 	u32 pflags = 0;
3092 
3093 	ASSERT_RTNL();
3094 
3095 	memset(&addr, 0, sizeof(struct in6_addr));
3096 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3097 
3098 	if (idev->dev->flags&IFF_POINTOPOINT) {
3099 		addr.s6_addr32[0] = htonl(0xfe800000);
3100 		scope = IFA_LINK;
3101 		plen = 64;
3102 	} else {
3103 		scope = IPV6_ADDR_COMPATv4;
3104 		plen = 96;
3105 		pflags |= RTF_NONEXTHOP;
3106 	}
3107 
3108 	if (addr.s6_addr32[3]) {
3109 		add_addr(idev, &addr, plen, scope);
3110 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3111 				      GFP_KERNEL);
3112 		return;
3113 	}
3114 
3115 	for_each_netdev(net, dev) {
3116 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3117 		if (in_dev && (dev->flags & IFF_UP)) {
3118 			struct in_ifaddr *ifa;
3119 			int flag = scope;
3120 
3121 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3122 				addr.s6_addr32[3] = ifa->ifa_local;
3123 
3124 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3125 					continue;
3126 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3127 					if (idev->dev->flags&IFF_POINTOPOINT)
3128 						continue;
3129 					flag |= IFA_HOST;
3130 				}
3131 
3132 				add_addr(idev, &addr, plen, flag);
3133 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3134 						      0, pflags, GFP_KERNEL);
3135 			}
3136 		}
3137 	}
3138 }
3139 #endif
3140 
3141 static void init_loopback(struct net_device *dev)
3142 {
3143 	struct inet6_dev  *idev;
3144 
3145 	/* ::1 */
3146 
3147 	ASSERT_RTNL();
3148 
3149 	idev = ipv6_find_idev(dev);
3150 	if (IS_ERR(idev)) {
3151 		pr_debug("%s: add_dev failed\n", __func__);
3152 		return;
3153 	}
3154 
3155 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3156 }
3157 
3158 void addrconf_add_linklocal(struct inet6_dev *idev,
3159 			    const struct in6_addr *addr, u32 flags)
3160 {
3161 	struct ifa6_config cfg = {
3162 		.pfx = addr,
3163 		.plen = 64,
3164 		.ifa_flags = flags | IFA_F_PERMANENT,
3165 		.valid_lft = INFINITY_LIFE_TIME,
3166 		.preferred_lft = INFINITY_LIFE_TIME,
3167 		.scope = IFA_LINK
3168 	};
3169 	struct inet6_ifaddr *ifp;
3170 
3171 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3172 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3173 	     idev->cnf.optimistic_dad) &&
3174 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3175 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3176 #endif
3177 
3178 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3179 	if (!IS_ERR(ifp)) {
3180 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3181 				      0, 0, GFP_ATOMIC);
3182 		addrconf_dad_start(ifp);
3183 		in6_ifa_put(ifp);
3184 	}
3185 }
3186 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3187 
3188 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3189 {
3190 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3191 		return true;
3192 
3193 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3194 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3195 		return true;
3196 
3197 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3198 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3199 		return true;
3200 
3201 	return false;
3202 }
3203 
3204 static int ipv6_generate_stable_address(struct in6_addr *address,
3205 					u8 dad_count,
3206 					const struct inet6_dev *idev)
3207 {
3208 	static DEFINE_SPINLOCK(lock);
3209 	static __u32 digest[SHA1_DIGEST_WORDS];
3210 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3211 
3212 	static union {
3213 		char __data[SHA1_BLOCK_SIZE];
3214 		struct {
3215 			struct in6_addr secret;
3216 			__be32 prefix[2];
3217 			unsigned char hwaddr[MAX_ADDR_LEN];
3218 			u8 dad_count;
3219 		} __packed;
3220 	} data;
3221 
3222 	struct in6_addr secret;
3223 	struct in6_addr temp;
3224 	struct net *net = dev_net(idev->dev);
3225 
3226 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3227 
3228 	if (idev->cnf.stable_secret.initialized)
3229 		secret = idev->cnf.stable_secret.secret;
3230 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3231 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3232 	else
3233 		return -1;
3234 
3235 retry:
3236 	spin_lock_bh(&lock);
3237 
3238 	sha1_init(digest);
3239 	memset(&data, 0, sizeof(data));
3240 	memset(workspace, 0, sizeof(workspace));
3241 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3242 	data.prefix[0] = address->s6_addr32[0];
3243 	data.prefix[1] = address->s6_addr32[1];
3244 	data.secret = secret;
3245 	data.dad_count = dad_count;
3246 
3247 	sha1_transform(digest, data.__data, workspace);
3248 
3249 	temp = *address;
3250 	temp.s6_addr32[2] = (__force __be32)digest[0];
3251 	temp.s6_addr32[3] = (__force __be32)digest[1];
3252 
3253 	spin_unlock_bh(&lock);
3254 
3255 	if (ipv6_reserved_interfaceid(temp)) {
3256 		dad_count++;
3257 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3258 			return -1;
3259 		goto retry;
3260 	}
3261 
3262 	*address = temp;
3263 	return 0;
3264 }
3265 
3266 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3267 {
3268 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3269 
3270 	if (s->initialized)
3271 		return;
3272 	s = &idev->cnf.stable_secret;
3273 	get_random_bytes(&s->secret, sizeof(s->secret));
3274 	s->initialized = true;
3275 }
3276 
3277 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3278 {
3279 	struct in6_addr addr;
3280 
3281 	/* no link local addresses on L3 master devices */
3282 	if (netif_is_l3_master(idev->dev))
3283 		return;
3284 
3285 	/* no link local addresses on devices flagged as slaves */
3286 	if (idev->dev->flags & IFF_SLAVE)
3287 		return;
3288 
3289 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3290 
3291 	switch (idev->cnf.addr_gen_mode) {
3292 	case IN6_ADDR_GEN_MODE_RANDOM:
3293 		ipv6_gen_mode_random_init(idev);
3294 		fallthrough;
3295 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3296 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3297 			addrconf_add_linklocal(idev, &addr,
3298 					       IFA_F_STABLE_PRIVACY);
3299 		else if (prefix_route)
3300 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3301 					      0, 0, GFP_KERNEL);
3302 		break;
3303 	case IN6_ADDR_GEN_MODE_EUI64:
3304 		/* addrconf_add_linklocal also adds a prefix_route and we
3305 		 * only need to care about prefix routes if ipv6_generate_eui64
3306 		 * couldn't generate one.
3307 		 */
3308 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3309 			addrconf_add_linklocal(idev, &addr, 0);
3310 		else if (prefix_route)
3311 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3312 					      0, 0, GFP_KERNEL);
3313 		break;
3314 	case IN6_ADDR_GEN_MODE_NONE:
3315 	default:
3316 		/* will not add any link local address */
3317 		break;
3318 	}
3319 }
3320 
3321 static void addrconf_dev_config(struct net_device *dev)
3322 {
3323 	struct inet6_dev *idev;
3324 
3325 	ASSERT_RTNL();
3326 
3327 	if ((dev->type != ARPHRD_ETHER) &&
3328 	    (dev->type != ARPHRD_FDDI) &&
3329 	    (dev->type != ARPHRD_ARCNET) &&
3330 	    (dev->type != ARPHRD_INFINIBAND) &&
3331 	    (dev->type != ARPHRD_IEEE1394) &&
3332 	    (dev->type != ARPHRD_TUNNEL6) &&
3333 	    (dev->type != ARPHRD_6LOWPAN) &&
3334 	    (dev->type != ARPHRD_IP6GRE) &&
3335 	    (dev->type != ARPHRD_IPGRE) &&
3336 	    (dev->type != ARPHRD_TUNNEL) &&
3337 	    (dev->type != ARPHRD_NONE) &&
3338 	    (dev->type != ARPHRD_RAWIP)) {
3339 		/* Alas, we support only Ethernet autoconfiguration. */
3340 		idev = __in6_dev_get(dev);
3341 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3342 		    dev->flags & IFF_MULTICAST)
3343 			ipv6_mc_up(idev);
3344 		return;
3345 	}
3346 
3347 	idev = addrconf_add_dev(dev);
3348 	if (IS_ERR(idev))
3349 		return;
3350 
3351 	/* this device type has no EUI support */
3352 	if (dev->type == ARPHRD_NONE &&
3353 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3354 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3355 
3356 	addrconf_addr_gen(idev, false);
3357 }
3358 
3359 #if IS_ENABLED(CONFIG_IPV6_SIT)
3360 static void addrconf_sit_config(struct net_device *dev)
3361 {
3362 	struct inet6_dev *idev;
3363 
3364 	ASSERT_RTNL();
3365 
3366 	/*
3367 	 * Configure the tunnel with one of our IPv4
3368 	 * addresses... we should configure all of
3369 	 * our v4 addrs in the tunnel
3370 	 */
3371 
3372 	idev = ipv6_find_idev(dev);
3373 	if (IS_ERR(idev)) {
3374 		pr_debug("%s: add_dev failed\n", __func__);
3375 		return;
3376 	}
3377 
3378 	if (dev->priv_flags & IFF_ISATAP) {
3379 		addrconf_addr_gen(idev, false);
3380 		return;
3381 	}
3382 
3383 	sit_add_v4_addrs(idev);
3384 
3385 	if (dev->flags&IFF_POINTOPOINT)
3386 		addrconf_add_mroute(dev);
3387 }
3388 #endif
3389 
3390 #if IS_ENABLED(CONFIG_NET_IPGRE)
3391 static void addrconf_gre_config(struct net_device *dev)
3392 {
3393 	struct inet6_dev *idev;
3394 
3395 	ASSERT_RTNL();
3396 
3397 	idev = ipv6_find_idev(dev);
3398 	if (IS_ERR(idev)) {
3399 		pr_debug("%s: add_dev failed\n", __func__);
3400 		return;
3401 	}
3402 
3403 	addrconf_addr_gen(idev, true);
3404 	if (dev->flags & IFF_POINTOPOINT)
3405 		addrconf_add_mroute(dev);
3406 }
3407 #endif
3408 
3409 static int fixup_permanent_addr(struct net *net,
3410 				struct inet6_dev *idev,
3411 				struct inet6_ifaddr *ifp)
3412 {
3413 	/* !fib6_node means the host route was removed from the
3414 	 * FIB, for example, if 'lo' device is taken down. In that
3415 	 * case regenerate the host route.
3416 	 */
3417 	if (!ifp->rt || !ifp->rt->fib6_node) {
3418 		struct fib6_info *f6i, *prev;
3419 
3420 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3421 					 GFP_ATOMIC);
3422 		if (IS_ERR(f6i))
3423 			return PTR_ERR(f6i);
3424 
3425 		/* ifp->rt can be accessed outside of rtnl */
3426 		spin_lock(&ifp->lock);
3427 		prev = ifp->rt;
3428 		ifp->rt = f6i;
3429 		spin_unlock(&ifp->lock);
3430 
3431 		fib6_info_release(prev);
3432 	}
3433 
3434 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3435 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3436 				      ifp->rt_priority, idev->dev, 0, 0,
3437 				      GFP_ATOMIC);
3438 	}
3439 
3440 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3441 		addrconf_dad_start(ifp);
3442 
3443 	return 0;
3444 }
3445 
3446 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3447 {
3448 	struct inet6_ifaddr *ifp, *tmp;
3449 	struct inet6_dev *idev;
3450 
3451 	idev = __in6_dev_get(dev);
3452 	if (!idev)
3453 		return;
3454 
3455 	write_lock_bh(&idev->lock);
3456 
3457 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3458 		if ((ifp->flags & IFA_F_PERMANENT) &&
3459 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3460 			write_unlock_bh(&idev->lock);
3461 			in6_ifa_hold(ifp);
3462 			ipv6_del_addr(ifp);
3463 			write_lock_bh(&idev->lock);
3464 
3465 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3466 					     idev->dev->name, &ifp->addr);
3467 		}
3468 	}
3469 
3470 	write_unlock_bh(&idev->lock);
3471 }
3472 
3473 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3474 			   void *ptr)
3475 {
3476 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3477 	struct netdev_notifier_change_info *change_info;
3478 	struct netdev_notifier_changeupper_info *info;
3479 	struct inet6_dev *idev = __in6_dev_get(dev);
3480 	struct net *net = dev_net(dev);
3481 	int run_pending = 0;
3482 	int err;
3483 
3484 	switch (event) {
3485 	case NETDEV_REGISTER:
3486 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3487 			idev = ipv6_add_dev(dev);
3488 			if (IS_ERR(idev))
3489 				return notifier_from_errno(PTR_ERR(idev));
3490 		}
3491 		break;
3492 
3493 	case NETDEV_CHANGEMTU:
3494 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3495 		if (dev->mtu < IPV6_MIN_MTU) {
3496 			addrconf_ifdown(dev, dev != net->loopback_dev);
3497 			break;
3498 		}
3499 
3500 		if (idev) {
3501 			rt6_mtu_change(dev, dev->mtu);
3502 			idev->cnf.mtu6 = dev->mtu;
3503 			break;
3504 		}
3505 
3506 		/* allocate new idev */
3507 		idev = ipv6_add_dev(dev);
3508 		if (IS_ERR(idev))
3509 			break;
3510 
3511 		/* device is still not ready */
3512 		if (!(idev->if_flags & IF_READY))
3513 			break;
3514 
3515 		run_pending = 1;
3516 		fallthrough;
3517 	case NETDEV_UP:
3518 	case NETDEV_CHANGE:
3519 		if (dev->flags & IFF_SLAVE)
3520 			break;
3521 
3522 		if (idev && idev->cnf.disable_ipv6)
3523 			break;
3524 
3525 		if (event == NETDEV_UP) {
3526 			/* restore routes for permanent addresses */
3527 			addrconf_permanent_addr(net, dev);
3528 
3529 			if (!addrconf_link_ready(dev)) {
3530 				/* device is not ready yet. */
3531 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3532 					 dev->name);
3533 				break;
3534 			}
3535 
3536 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3537 				idev = ipv6_add_dev(dev);
3538 
3539 			if (!IS_ERR_OR_NULL(idev)) {
3540 				idev->if_flags |= IF_READY;
3541 				run_pending = 1;
3542 			}
3543 		} else if (event == NETDEV_CHANGE) {
3544 			if (!addrconf_link_ready(dev)) {
3545 				/* device is still not ready. */
3546 				rt6_sync_down_dev(dev, event);
3547 				break;
3548 			}
3549 
3550 			if (!IS_ERR_OR_NULL(idev)) {
3551 				if (idev->if_flags & IF_READY) {
3552 					/* device is already configured -
3553 					 * but resend MLD reports, we might
3554 					 * have roamed and need to update
3555 					 * multicast snooping switches
3556 					 */
3557 					ipv6_mc_up(idev);
3558 					change_info = ptr;
3559 					if (change_info->flags_changed & IFF_NOARP)
3560 						addrconf_dad_run(idev, true);
3561 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3562 					break;
3563 				}
3564 				idev->if_flags |= IF_READY;
3565 			}
3566 
3567 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3568 				dev->name);
3569 
3570 			run_pending = 1;
3571 		}
3572 
3573 		switch (dev->type) {
3574 #if IS_ENABLED(CONFIG_IPV6_SIT)
3575 		case ARPHRD_SIT:
3576 			addrconf_sit_config(dev);
3577 			break;
3578 #endif
3579 #if IS_ENABLED(CONFIG_NET_IPGRE)
3580 		case ARPHRD_IPGRE:
3581 			addrconf_gre_config(dev);
3582 			break;
3583 #endif
3584 		case ARPHRD_LOOPBACK:
3585 			init_loopback(dev);
3586 			break;
3587 
3588 		default:
3589 			addrconf_dev_config(dev);
3590 			break;
3591 		}
3592 
3593 		if (!IS_ERR_OR_NULL(idev)) {
3594 			if (run_pending)
3595 				addrconf_dad_run(idev, false);
3596 
3597 			/* Device has an address by now */
3598 			rt6_sync_up(dev, RTNH_F_DEAD);
3599 
3600 			/*
3601 			 * If the MTU changed during the interface down,
3602 			 * when the interface up, the changed MTU must be
3603 			 * reflected in the idev as well as routers.
3604 			 */
3605 			if (idev->cnf.mtu6 != dev->mtu &&
3606 			    dev->mtu >= IPV6_MIN_MTU) {
3607 				rt6_mtu_change(dev, dev->mtu);
3608 				idev->cnf.mtu6 = dev->mtu;
3609 			}
3610 			idev->tstamp = jiffies;
3611 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3612 
3613 			/*
3614 			 * If the changed mtu during down is lower than
3615 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3616 			 */
3617 			if (dev->mtu < IPV6_MIN_MTU)
3618 				addrconf_ifdown(dev, dev != net->loopback_dev);
3619 		}
3620 		break;
3621 
3622 	case NETDEV_DOWN:
3623 	case NETDEV_UNREGISTER:
3624 		/*
3625 		 *	Remove all addresses from this interface.
3626 		 */
3627 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3628 		break;
3629 
3630 	case NETDEV_CHANGENAME:
3631 		if (idev) {
3632 			snmp6_unregister_dev(idev);
3633 			addrconf_sysctl_unregister(idev);
3634 			err = addrconf_sysctl_register(idev);
3635 			if (err)
3636 				return notifier_from_errno(err);
3637 			err = snmp6_register_dev(idev);
3638 			if (err) {
3639 				addrconf_sysctl_unregister(idev);
3640 				return notifier_from_errno(err);
3641 			}
3642 		}
3643 		break;
3644 
3645 	case NETDEV_PRE_TYPE_CHANGE:
3646 	case NETDEV_POST_TYPE_CHANGE:
3647 		if (idev)
3648 			addrconf_type_change(dev, event);
3649 		break;
3650 
3651 	case NETDEV_CHANGEUPPER:
3652 		info = ptr;
3653 
3654 		/* flush all routes if dev is linked to or unlinked from
3655 		 * an L3 master device (e.g., VRF)
3656 		 */
3657 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3658 			addrconf_ifdown(dev, false);
3659 	}
3660 
3661 	return NOTIFY_OK;
3662 }
3663 
3664 /*
3665  *	addrconf module should be notified of a device going up
3666  */
3667 static struct notifier_block ipv6_dev_notf = {
3668 	.notifier_call = addrconf_notify,
3669 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3670 };
3671 
3672 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3673 {
3674 	struct inet6_dev *idev;
3675 	ASSERT_RTNL();
3676 
3677 	idev = __in6_dev_get(dev);
3678 
3679 	if (event == NETDEV_POST_TYPE_CHANGE)
3680 		ipv6_mc_remap(idev);
3681 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3682 		ipv6_mc_unmap(idev);
3683 }
3684 
3685 static bool addr_is_local(const struct in6_addr *addr)
3686 {
3687 	return ipv6_addr_type(addr) &
3688 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3689 }
3690 
3691 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3692 {
3693 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3694 	struct net *net = dev_net(dev);
3695 	struct inet6_dev *idev;
3696 	struct inet6_ifaddr *ifa, *tmp;
3697 	bool keep_addr = false;
3698 	int state, i;
3699 
3700 	ASSERT_RTNL();
3701 
3702 	rt6_disable_ip(dev, event);
3703 
3704 	idev = __in6_dev_get(dev);
3705 	if (!idev)
3706 		return -ENODEV;
3707 
3708 	/*
3709 	 * Step 1: remove reference to ipv6 device from parent device.
3710 	 *	   Do not dev_put!
3711 	 */
3712 	if (unregister) {
3713 		idev->dead = 1;
3714 
3715 		/* protected by rtnl_lock */
3716 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3717 
3718 		/* Step 1.5: remove snmp6 entry */
3719 		snmp6_unregister_dev(idev);
3720 
3721 	}
3722 
3723 	/* combine the user config with event to determine if permanent
3724 	 * addresses are to be removed from address hash table
3725 	 */
3726 	if (!unregister && !idev->cnf.disable_ipv6) {
3727 		/* aggregate the system setting and interface setting */
3728 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3729 
3730 		if (!_keep_addr)
3731 			_keep_addr = idev->cnf.keep_addr_on_down;
3732 
3733 		keep_addr = (_keep_addr > 0);
3734 	}
3735 
3736 	/* Step 2: clear hash table */
3737 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3738 		struct hlist_head *h = &inet6_addr_lst[i];
3739 
3740 		spin_lock_bh(&addrconf_hash_lock);
3741 restart:
3742 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3743 			if (ifa->idev == idev) {
3744 				addrconf_del_dad_work(ifa);
3745 				/* combined flag + permanent flag decide if
3746 				 * address is retained on a down event
3747 				 */
3748 				if (!keep_addr ||
3749 				    !(ifa->flags & IFA_F_PERMANENT) ||
3750 				    addr_is_local(&ifa->addr)) {
3751 					hlist_del_init_rcu(&ifa->addr_lst);
3752 					goto restart;
3753 				}
3754 			}
3755 		}
3756 		spin_unlock_bh(&addrconf_hash_lock);
3757 	}
3758 
3759 	write_lock_bh(&idev->lock);
3760 
3761 	addrconf_del_rs_timer(idev);
3762 
3763 	/* Step 2: clear flags for stateless addrconf */
3764 	if (!unregister)
3765 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3766 
3767 	/* Step 3: clear tempaddr list */
3768 	while (!list_empty(&idev->tempaddr_list)) {
3769 		ifa = list_first_entry(&idev->tempaddr_list,
3770 				       struct inet6_ifaddr, tmp_list);
3771 		list_del(&ifa->tmp_list);
3772 		write_unlock_bh(&idev->lock);
3773 		spin_lock_bh(&ifa->lock);
3774 
3775 		if (ifa->ifpub) {
3776 			in6_ifa_put(ifa->ifpub);
3777 			ifa->ifpub = NULL;
3778 		}
3779 		spin_unlock_bh(&ifa->lock);
3780 		in6_ifa_put(ifa);
3781 		write_lock_bh(&idev->lock);
3782 	}
3783 
3784 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3785 		struct fib6_info *rt = NULL;
3786 		bool keep;
3787 
3788 		addrconf_del_dad_work(ifa);
3789 
3790 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3791 			!addr_is_local(&ifa->addr);
3792 
3793 		write_unlock_bh(&idev->lock);
3794 		spin_lock_bh(&ifa->lock);
3795 
3796 		if (keep) {
3797 			/* set state to skip the notifier below */
3798 			state = INET6_IFADDR_STATE_DEAD;
3799 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3800 			if (!(ifa->flags & IFA_F_NODAD))
3801 				ifa->flags |= IFA_F_TENTATIVE;
3802 
3803 			rt = ifa->rt;
3804 			ifa->rt = NULL;
3805 		} else {
3806 			state = ifa->state;
3807 			ifa->state = INET6_IFADDR_STATE_DEAD;
3808 		}
3809 
3810 		spin_unlock_bh(&ifa->lock);
3811 
3812 		if (rt)
3813 			ip6_del_rt(net, rt, false);
3814 
3815 		if (state != INET6_IFADDR_STATE_DEAD) {
3816 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3817 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3818 		} else {
3819 			if (idev->cnf.forwarding)
3820 				addrconf_leave_anycast(ifa);
3821 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3822 		}
3823 
3824 		write_lock_bh(&idev->lock);
3825 		if (!keep) {
3826 			list_del_rcu(&ifa->if_list);
3827 			in6_ifa_put(ifa);
3828 		}
3829 	}
3830 
3831 	write_unlock_bh(&idev->lock);
3832 
3833 	/* Step 5: Discard anycast and multicast list */
3834 	if (unregister) {
3835 		ipv6_ac_destroy_dev(idev);
3836 		ipv6_mc_destroy_dev(idev);
3837 	} else {
3838 		ipv6_mc_down(idev);
3839 	}
3840 
3841 	idev->tstamp = jiffies;
3842 
3843 	/* Last: Shot the device (if unregistered) */
3844 	if (unregister) {
3845 		addrconf_sysctl_unregister(idev);
3846 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3847 		neigh_ifdown(&nd_tbl, dev);
3848 		in6_dev_put(idev);
3849 	}
3850 	return 0;
3851 }
3852 
3853 static void addrconf_rs_timer(struct timer_list *t)
3854 {
3855 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3856 	struct net_device *dev = idev->dev;
3857 	struct in6_addr lladdr;
3858 
3859 	write_lock(&idev->lock);
3860 	if (idev->dead || !(idev->if_flags & IF_READY))
3861 		goto out;
3862 
3863 	if (!ipv6_accept_ra(idev))
3864 		goto out;
3865 
3866 	/* Announcement received after solicitation was sent */
3867 	if (idev->if_flags & IF_RA_RCVD)
3868 		goto out;
3869 
3870 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3871 		write_unlock(&idev->lock);
3872 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3873 			ndisc_send_rs(dev, &lladdr,
3874 				      &in6addr_linklocal_allrouters);
3875 		else
3876 			goto put;
3877 
3878 		write_lock(&idev->lock);
3879 		idev->rs_interval = rfc3315_s14_backoff_update(
3880 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3881 		/* The wait after the last probe can be shorter */
3882 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3883 					     idev->cnf.rtr_solicits) ?
3884 				      idev->cnf.rtr_solicit_delay :
3885 				      idev->rs_interval);
3886 	} else {
3887 		/*
3888 		 * Note: we do not support deprecated "all on-link"
3889 		 * assumption any longer.
3890 		 */
3891 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3892 	}
3893 
3894 out:
3895 	write_unlock(&idev->lock);
3896 put:
3897 	in6_dev_put(idev);
3898 }
3899 
3900 /*
3901  *	Duplicate Address Detection
3902  */
3903 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3904 {
3905 	unsigned long rand_num;
3906 	struct inet6_dev *idev = ifp->idev;
3907 	u64 nonce;
3908 
3909 	if (ifp->flags & IFA_F_OPTIMISTIC)
3910 		rand_num = 0;
3911 	else
3912 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3913 
3914 	nonce = 0;
3915 	if (idev->cnf.enhanced_dad ||
3916 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3917 		do
3918 			get_random_bytes(&nonce, 6);
3919 		while (nonce == 0);
3920 	}
3921 	ifp->dad_nonce = nonce;
3922 	ifp->dad_probes = idev->cnf.dad_transmits;
3923 	addrconf_mod_dad_work(ifp, rand_num);
3924 }
3925 
3926 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3927 {
3928 	struct inet6_dev *idev = ifp->idev;
3929 	struct net_device *dev = idev->dev;
3930 	bool bump_id, notify = false;
3931 	struct net *net;
3932 
3933 	addrconf_join_solict(dev, &ifp->addr);
3934 
3935 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3936 
3937 	read_lock_bh(&idev->lock);
3938 	spin_lock(&ifp->lock);
3939 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3940 		goto out;
3941 
3942 	net = dev_net(dev);
3943 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3944 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3945 	     idev->cnf.accept_dad < 1) ||
3946 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3947 	    ifp->flags & IFA_F_NODAD) {
3948 		bool send_na = false;
3949 
3950 		if (ifp->flags & IFA_F_TENTATIVE &&
3951 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3952 			send_na = true;
3953 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3954 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3955 		spin_unlock(&ifp->lock);
3956 		read_unlock_bh(&idev->lock);
3957 
3958 		addrconf_dad_completed(ifp, bump_id, send_na);
3959 		return;
3960 	}
3961 
3962 	if (!(idev->if_flags & IF_READY)) {
3963 		spin_unlock(&ifp->lock);
3964 		read_unlock_bh(&idev->lock);
3965 		/*
3966 		 * If the device is not ready:
3967 		 * - keep it tentative if it is a permanent address.
3968 		 * - otherwise, kill it.
3969 		 */
3970 		in6_ifa_hold(ifp);
3971 		addrconf_dad_stop(ifp, 0);
3972 		return;
3973 	}
3974 
3975 	/*
3976 	 * Optimistic nodes can start receiving
3977 	 * Frames right away
3978 	 */
3979 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3980 		ip6_ins_rt(net, ifp->rt);
3981 		if (ipv6_use_optimistic_addr(net, idev)) {
3982 			/* Because optimistic nodes can use this address,
3983 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3984 			 */
3985 			notify = true;
3986 		}
3987 	}
3988 
3989 	addrconf_dad_kick(ifp);
3990 out:
3991 	spin_unlock(&ifp->lock);
3992 	read_unlock_bh(&idev->lock);
3993 	if (notify)
3994 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3995 }
3996 
3997 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3998 {
3999 	bool begin_dad = false;
4000 
4001 	spin_lock_bh(&ifp->lock);
4002 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4003 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4004 		begin_dad = true;
4005 	}
4006 	spin_unlock_bh(&ifp->lock);
4007 
4008 	if (begin_dad)
4009 		addrconf_mod_dad_work(ifp, 0);
4010 }
4011 
4012 static void addrconf_dad_work(struct work_struct *w)
4013 {
4014 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4015 						struct inet6_ifaddr,
4016 						dad_work);
4017 	struct inet6_dev *idev = ifp->idev;
4018 	bool bump_id, disable_ipv6 = false;
4019 	struct in6_addr mcaddr;
4020 
4021 	enum {
4022 		DAD_PROCESS,
4023 		DAD_BEGIN,
4024 		DAD_ABORT,
4025 	} action = DAD_PROCESS;
4026 
4027 	rtnl_lock();
4028 
4029 	spin_lock_bh(&ifp->lock);
4030 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4031 		action = DAD_BEGIN;
4032 		ifp->state = INET6_IFADDR_STATE_DAD;
4033 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4034 		action = DAD_ABORT;
4035 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4036 
4037 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4038 		     idev->cnf.accept_dad > 1) &&
4039 		    !idev->cnf.disable_ipv6 &&
4040 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4041 			struct in6_addr addr;
4042 
4043 			addr.s6_addr32[0] = htonl(0xfe800000);
4044 			addr.s6_addr32[1] = 0;
4045 
4046 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4047 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4048 				/* DAD failed for link-local based on MAC */
4049 				idev->cnf.disable_ipv6 = 1;
4050 
4051 				pr_info("%s: IPv6 being disabled!\n",
4052 					ifp->idev->dev->name);
4053 				disable_ipv6 = true;
4054 			}
4055 		}
4056 	}
4057 	spin_unlock_bh(&ifp->lock);
4058 
4059 	if (action == DAD_BEGIN) {
4060 		addrconf_dad_begin(ifp);
4061 		goto out;
4062 	} else if (action == DAD_ABORT) {
4063 		in6_ifa_hold(ifp);
4064 		addrconf_dad_stop(ifp, 1);
4065 		if (disable_ipv6)
4066 			addrconf_ifdown(idev->dev, false);
4067 		goto out;
4068 	}
4069 
4070 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4071 		goto out;
4072 
4073 	write_lock_bh(&idev->lock);
4074 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4075 		write_unlock_bh(&idev->lock);
4076 		goto out;
4077 	}
4078 
4079 	spin_lock(&ifp->lock);
4080 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4081 		spin_unlock(&ifp->lock);
4082 		write_unlock_bh(&idev->lock);
4083 		goto out;
4084 	}
4085 
4086 	if (ifp->dad_probes == 0) {
4087 		bool send_na = false;
4088 
4089 		/*
4090 		 * DAD was successful
4091 		 */
4092 
4093 		if (ifp->flags & IFA_F_TENTATIVE &&
4094 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4095 			send_na = true;
4096 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4097 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4098 		spin_unlock(&ifp->lock);
4099 		write_unlock_bh(&idev->lock);
4100 
4101 		addrconf_dad_completed(ifp, bump_id, send_na);
4102 
4103 		goto out;
4104 	}
4105 
4106 	ifp->dad_probes--;
4107 	addrconf_mod_dad_work(ifp,
4108 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4109 				  HZ/100));
4110 	spin_unlock(&ifp->lock);
4111 	write_unlock_bh(&idev->lock);
4112 
4113 	/* send a neighbour solicitation for our addr */
4114 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4115 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4116 		      ifp->dad_nonce);
4117 out:
4118 	in6_ifa_put(ifp);
4119 	rtnl_unlock();
4120 }
4121 
4122 /* ifp->idev must be at least read locked */
4123 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4124 {
4125 	struct inet6_ifaddr *ifpiter;
4126 	struct inet6_dev *idev = ifp->idev;
4127 
4128 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4129 		if (ifpiter->scope > IFA_LINK)
4130 			break;
4131 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4132 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4133 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4134 		    IFA_F_PERMANENT)
4135 			return false;
4136 	}
4137 	return true;
4138 }
4139 
4140 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4141 				   bool send_na)
4142 {
4143 	struct net_device *dev = ifp->idev->dev;
4144 	struct in6_addr lladdr;
4145 	bool send_rs, send_mld;
4146 
4147 	addrconf_del_dad_work(ifp);
4148 
4149 	/*
4150 	 *	Configure the address for reception. Now it is valid.
4151 	 */
4152 
4153 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4154 
4155 	/* If added prefix is link local and we are prepared to process
4156 	   router advertisements, start sending router solicitations.
4157 	 */
4158 
4159 	read_lock_bh(&ifp->idev->lock);
4160 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4161 	send_rs = send_mld &&
4162 		  ipv6_accept_ra(ifp->idev) &&
4163 		  ifp->idev->cnf.rtr_solicits != 0 &&
4164 		  (dev->flags&IFF_LOOPBACK) == 0;
4165 	read_unlock_bh(&ifp->idev->lock);
4166 
4167 	/* While dad is in progress mld report's source address is in6_addrany.
4168 	 * Resend with proper ll now.
4169 	 */
4170 	if (send_mld)
4171 		ipv6_mc_dad_complete(ifp->idev);
4172 
4173 	/* send unsolicited NA if enabled */
4174 	if (send_na &&
4175 	    (ifp->idev->cnf.ndisc_notify ||
4176 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4177 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4178 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4179 			      /*solicited=*/ false, /*override=*/ true,
4180 			      /*inc_opt=*/ true);
4181 	}
4182 
4183 	if (send_rs) {
4184 		/*
4185 		 *	If a host as already performed a random delay
4186 		 *	[...] as part of DAD [...] there is no need
4187 		 *	to delay again before sending the first RS
4188 		 */
4189 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4190 			return;
4191 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4192 
4193 		write_lock_bh(&ifp->idev->lock);
4194 		spin_lock(&ifp->lock);
4195 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4196 			ifp->idev->cnf.rtr_solicit_interval);
4197 		ifp->idev->rs_probes = 1;
4198 		ifp->idev->if_flags |= IF_RS_SENT;
4199 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4200 		spin_unlock(&ifp->lock);
4201 		write_unlock_bh(&ifp->idev->lock);
4202 	}
4203 
4204 	if (bump_id)
4205 		rt_genid_bump_ipv6(dev_net(dev));
4206 
4207 	/* Make sure that a new temporary address will be created
4208 	 * before this temporary address becomes deprecated.
4209 	 */
4210 	if (ifp->flags & IFA_F_TEMPORARY)
4211 		addrconf_verify_rtnl();
4212 }
4213 
4214 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4215 {
4216 	struct inet6_ifaddr *ifp;
4217 
4218 	read_lock_bh(&idev->lock);
4219 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4220 		spin_lock(&ifp->lock);
4221 		if ((ifp->flags & IFA_F_TENTATIVE &&
4222 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4223 			if (restart)
4224 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4225 			addrconf_dad_kick(ifp);
4226 		}
4227 		spin_unlock(&ifp->lock);
4228 	}
4229 	read_unlock_bh(&idev->lock);
4230 }
4231 
4232 #ifdef CONFIG_PROC_FS
4233 struct if6_iter_state {
4234 	struct seq_net_private p;
4235 	int bucket;
4236 	int offset;
4237 };
4238 
4239 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4240 {
4241 	struct if6_iter_state *state = seq->private;
4242 	struct net *net = seq_file_net(seq);
4243 	struct inet6_ifaddr *ifa = NULL;
4244 	int p = 0;
4245 
4246 	/* initial bucket if pos is 0 */
4247 	if (pos == 0) {
4248 		state->bucket = 0;
4249 		state->offset = 0;
4250 	}
4251 
4252 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4253 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4254 					 addr_lst) {
4255 			if (!net_eq(dev_net(ifa->idev->dev), net))
4256 				continue;
4257 			/* sync with offset */
4258 			if (p < state->offset) {
4259 				p++;
4260 				continue;
4261 			}
4262 			return ifa;
4263 		}
4264 
4265 		/* prepare for next bucket */
4266 		state->offset = 0;
4267 		p = 0;
4268 	}
4269 	return NULL;
4270 }
4271 
4272 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4273 					 struct inet6_ifaddr *ifa)
4274 {
4275 	struct if6_iter_state *state = seq->private;
4276 	struct net *net = seq_file_net(seq);
4277 
4278 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4279 		if (!net_eq(dev_net(ifa->idev->dev), net))
4280 			continue;
4281 		state->offset++;
4282 		return ifa;
4283 	}
4284 
4285 	state->offset = 0;
4286 	while (++state->bucket < IN6_ADDR_HSIZE) {
4287 		hlist_for_each_entry_rcu(ifa,
4288 				     &inet6_addr_lst[state->bucket], addr_lst) {
4289 			if (!net_eq(dev_net(ifa->idev->dev), net))
4290 				continue;
4291 			return ifa;
4292 		}
4293 	}
4294 
4295 	return NULL;
4296 }
4297 
4298 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4299 	__acquires(rcu)
4300 {
4301 	rcu_read_lock();
4302 	return if6_get_first(seq, *pos);
4303 }
4304 
4305 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4306 {
4307 	struct inet6_ifaddr *ifa;
4308 
4309 	ifa = if6_get_next(seq, v);
4310 	++*pos;
4311 	return ifa;
4312 }
4313 
4314 static void if6_seq_stop(struct seq_file *seq, void *v)
4315 	__releases(rcu)
4316 {
4317 	rcu_read_unlock();
4318 }
4319 
4320 static int if6_seq_show(struct seq_file *seq, void *v)
4321 {
4322 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4323 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4324 		   &ifp->addr,
4325 		   ifp->idev->dev->ifindex,
4326 		   ifp->prefix_len,
4327 		   ifp->scope,
4328 		   (u8) ifp->flags,
4329 		   ifp->idev->dev->name);
4330 	return 0;
4331 }
4332 
4333 static const struct seq_operations if6_seq_ops = {
4334 	.start	= if6_seq_start,
4335 	.next	= if6_seq_next,
4336 	.show	= if6_seq_show,
4337 	.stop	= if6_seq_stop,
4338 };
4339 
4340 static int __net_init if6_proc_net_init(struct net *net)
4341 {
4342 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4343 			sizeof(struct if6_iter_state)))
4344 		return -ENOMEM;
4345 	return 0;
4346 }
4347 
4348 static void __net_exit if6_proc_net_exit(struct net *net)
4349 {
4350 	remove_proc_entry("if_inet6", net->proc_net);
4351 }
4352 
4353 static struct pernet_operations if6_proc_net_ops = {
4354 	.init = if6_proc_net_init,
4355 	.exit = if6_proc_net_exit,
4356 };
4357 
4358 int __init if6_proc_init(void)
4359 {
4360 	return register_pernet_subsys(&if6_proc_net_ops);
4361 }
4362 
4363 void if6_proc_exit(void)
4364 {
4365 	unregister_pernet_subsys(&if6_proc_net_ops);
4366 }
4367 #endif	/* CONFIG_PROC_FS */
4368 
4369 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4370 /* Check if address is a home address configured on any interface. */
4371 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4372 {
4373 	unsigned int hash = inet6_addr_hash(net, addr);
4374 	struct inet6_ifaddr *ifp = NULL;
4375 	int ret = 0;
4376 
4377 	rcu_read_lock();
4378 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4379 		if (!net_eq(dev_net(ifp->idev->dev), net))
4380 			continue;
4381 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4382 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4383 			ret = 1;
4384 			break;
4385 		}
4386 	}
4387 	rcu_read_unlock();
4388 	return ret;
4389 }
4390 #endif
4391 
4392 /* RFC6554 has some algorithm to avoid loops in segment routing by
4393  * checking if the segments contains any of a local interface address.
4394  *
4395  * Quote:
4396  *
4397  * To detect loops in the SRH, a router MUST determine if the SRH
4398  * includes multiple addresses assigned to any interface on that router.
4399  * If such addresses appear more than once and are separated by at least
4400  * one address not assigned to that router.
4401  */
4402 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4403 			  unsigned char nsegs)
4404 {
4405 	const struct in6_addr *addr;
4406 	int i, ret = 0, found = 0;
4407 	struct inet6_ifaddr *ifp;
4408 	bool separated = false;
4409 	unsigned int hash;
4410 	bool hash_found;
4411 
4412 	rcu_read_lock();
4413 	for (i = 0; i < nsegs; i++) {
4414 		addr = &segs[i];
4415 		hash = inet6_addr_hash(net, addr);
4416 
4417 		hash_found = false;
4418 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4419 			if (!net_eq(dev_net(ifp->idev->dev), net))
4420 				continue;
4421 
4422 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4423 				hash_found = true;
4424 				break;
4425 			}
4426 		}
4427 
4428 		if (hash_found) {
4429 			if (found > 1 && separated) {
4430 				ret = 1;
4431 				break;
4432 			}
4433 
4434 			separated = false;
4435 			found++;
4436 		} else {
4437 			separated = true;
4438 		}
4439 	}
4440 	rcu_read_unlock();
4441 
4442 	return ret;
4443 }
4444 
4445 /*
4446  *	Periodic address status verification
4447  */
4448 
4449 static void addrconf_verify_rtnl(void)
4450 {
4451 	unsigned long now, next, next_sec, next_sched;
4452 	struct inet6_ifaddr *ifp;
4453 	int i;
4454 
4455 	ASSERT_RTNL();
4456 
4457 	rcu_read_lock_bh();
4458 	now = jiffies;
4459 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4460 
4461 	cancel_delayed_work(&addr_chk_work);
4462 
4463 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4464 restart:
4465 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4466 			unsigned long age;
4467 
4468 			/* When setting preferred_lft to a value not zero or
4469 			 * infinity, while valid_lft is infinity
4470 			 * IFA_F_PERMANENT has a non-infinity life time.
4471 			 */
4472 			if ((ifp->flags & IFA_F_PERMANENT) &&
4473 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4474 				continue;
4475 
4476 			spin_lock(&ifp->lock);
4477 			/* We try to batch several events at once. */
4478 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4479 
4480 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4481 			    age >= ifp->valid_lft) {
4482 				spin_unlock(&ifp->lock);
4483 				in6_ifa_hold(ifp);
4484 				ipv6_del_addr(ifp);
4485 				goto restart;
4486 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4487 				spin_unlock(&ifp->lock);
4488 				continue;
4489 			} else if (age >= ifp->prefered_lft) {
4490 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4491 				int deprecate = 0;
4492 
4493 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4494 					deprecate = 1;
4495 					ifp->flags |= IFA_F_DEPRECATED;
4496 				}
4497 
4498 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4499 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4500 					next = ifp->tstamp + ifp->valid_lft * HZ;
4501 
4502 				spin_unlock(&ifp->lock);
4503 
4504 				if (deprecate) {
4505 					in6_ifa_hold(ifp);
4506 
4507 					ipv6_ifa_notify(0, ifp);
4508 					in6_ifa_put(ifp);
4509 					goto restart;
4510 				}
4511 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4512 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4513 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4514 					ifp->idev->cnf.dad_transmits *
4515 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4516 
4517 				if (age >= ifp->prefered_lft - regen_advance) {
4518 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4519 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4520 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4521 					if (!ifp->regen_count && ifpub) {
4522 						ifp->regen_count++;
4523 						in6_ifa_hold(ifp);
4524 						in6_ifa_hold(ifpub);
4525 						spin_unlock(&ifp->lock);
4526 
4527 						spin_lock(&ifpub->lock);
4528 						ifpub->regen_count = 0;
4529 						spin_unlock(&ifpub->lock);
4530 						rcu_read_unlock_bh();
4531 						ipv6_create_tempaddr(ifpub, true);
4532 						in6_ifa_put(ifpub);
4533 						in6_ifa_put(ifp);
4534 						rcu_read_lock_bh();
4535 						goto restart;
4536 					}
4537 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4538 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4539 				spin_unlock(&ifp->lock);
4540 			} else {
4541 				/* ifp->prefered_lft <= ifp->valid_lft */
4542 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4543 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4544 				spin_unlock(&ifp->lock);
4545 			}
4546 		}
4547 	}
4548 
4549 	next_sec = round_jiffies_up(next);
4550 	next_sched = next;
4551 
4552 	/* If rounded timeout is accurate enough, accept it. */
4553 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4554 		next_sched = next_sec;
4555 
4556 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4557 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4558 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4559 
4560 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4561 		 now, next, next_sec, next_sched);
4562 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4563 	rcu_read_unlock_bh();
4564 }
4565 
4566 static void addrconf_verify_work(struct work_struct *w)
4567 {
4568 	rtnl_lock();
4569 	addrconf_verify_rtnl();
4570 	rtnl_unlock();
4571 }
4572 
4573 static void addrconf_verify(void)
4574 {
4575 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4576 }
4577 
4578 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4579 				     struct in6_addr **peer_pfx)
4580 {
4581 	struct in6_addr *pfx = NULL;
4582 
4583 	*peer_pfx = NULL;
4584 
4585 	if (addr)
4586 		pfx = nla_data(addr);
4587 
4588 	if (local) {
4589 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4590 			*peer_pfx = pfx;
4591 		pfx = nla_data(local);
4592 	}
4593 
4594 	return pfx;
4595 }
4596 
4597 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4598 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4599 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4600 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4601 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4602 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4603 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4604 };
4605 
4606 static int
4607 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4608 		  struct netlink_ext_ack *extack)
4609 {
4610 	struct net *net = sock_net(skb->sk);
4611 	struct ifaddrmsg *ifm;
4612 	struct nlattr *tb[IFA_MAX+1];
4613 	struct in6_addr *pfx, *peer_pfx;
4614 	u32 ifa_flags;
4615 	int err;
4616 
4617 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4618 				     ifa_ipv6_policy, extack);
4619 	if (err < 0)
4620 		return err;
4621 
4622 	ifm = nlmsg_data(nlh);
4623 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4624 	if (!pfx)
4625 		return -EINVAL;
4626 
4627 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4628 
4629 	/* We ignore other flags so far. */
4630 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4631 
4632 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4633 			      ifm->ifa_prefixlen);
4634 }
4635 
4636 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4637 			       unsigned long expires, u32 flags,
4638 			       bool modify_peer)
4639 {
4640 	struct fib6_info *f6i;
4641 	u32 prio;
4642 
4643 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4644 					ifp->prefix_len,
4645 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4646 	if (!f6i)
4647 		return -ENOENT;
4648 
4649 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4650 	if (f6i->fib6_metric != prio) {
4651 		/* delete old one */
4652 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4653 
4654 		/* add new one */
4655 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4656 				      ifp->prefix_len,
4657 				      ifp->rt_priority, ifp->idev->dev,
4658 				      expires, flags, GFP_KERNEL);
4659 	} else {
4660 		if (!expires)
4661 			fib6_clean_expires(f6i);
4662 		else
4663 			fib6_set_expires(f6i, expires);
4664 
4665 		fib6_info_release(f6i);
4666 	}
4667 
4668 	return 0;
4669 }
4670 
4671 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4672 {
4673 	u32 flags;
4674 	clock_t expires;
4675 	unsigned long timeout;
4676 	bool was_managetempaddr;
4677 	bool had_prefixroute;
4678 	bool new_peer = false;
4679 
4680 	ASSERT_RTNL();
4681 
4682 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4683 		return -EINVAL;
4684 
4685 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4686 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4687 		return -EINVAL;
4688 
4689 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4690 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4691 
4692 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4693 	if (addrconf_finite_timeout(timeout)) {
4694 		expires = jiffies_to_clock_t(timeout * HZ);
4695 		cfg->valid_lft = timeout;
4696 		flags = RTF_EXPIRES;
4697 	} else {
4698 		expires = 0;
4699 		flags = 0;
4700 		cfg->ifa_flags |= IFA_F_PERMANENT;
4701 	}
4702 
4703 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4704 	if (addrconf_finite_timeout(timeout)) {
4705 		if (timeout == 0)
4706 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4707 		cfg->preferred_lft = timeout;
4708 	}
4709 
4710 	if (cfg->peer_pfx &&
4711 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4712 		if (!ipv6_addr_any(&ifp->peer_addr))
4713 			cleanup_prefix_route(ifp, expires, true, true);
4714 		new_peer = true;
4715 	}
4716 
4717 	spin_lock_bh(&ifp->lock);
4718 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4719 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4720 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4721 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4722 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4723 			IFA_F_NOPREFIXROUTE);
4724 	ifp->flags |= cfg->ifa_flags;
4725 	ifp->tstamp = jiffies;
4726 	ifp->valid_lft = cfg->valid_lft;
4727 	ifp->prefered_lft = cfg->preferred_lft;
4728 
4729 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4730 		ifp->rt_priority = cfg->rt_priority;
4731 
4732 	if (new_peer)
4733 		ifp->peer_addr = *cfg->peer_pfx;
4734 
4735 	spin_unlock_bh(&ifp->lock);
4736 	if (!(ifp->flags&IFA_F_TENTATIVE))
4737 		ipv6_ifa_notify(0, ifp);
4738 
4739 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4740 		int rc = -ENOENT;
4741 
4742 		if (had_prefixroute)
4743 			rc = modify_prefix_route(ifp, expires, flags, false);
4744 
4745 		/* prefix route could have been deleted; if so restore it */
4746 		if (rc == -ENOENT) {
4747 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4748 					      ifp->rt_priority, ifp->idev->dev,
4749 					      expires, flags, GFP_KERNEL);
4750 		}
4751 
4752 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4753 			rc = modify_prefix_route(ifp, expires, flags, true);
4754 
4755 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4756 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4757 					      ifp->rt_priority, ifp->idev->dev,
4758 					      expires, flags, GFP_KERNEL);
4759 		}
4760 	} else if (had_prefixroute) {
4761 		enum cleanup_prefix_rt_t action;
4762 		unsigned long rt_expires;
4763 
4764 		write_lock_bh(&ifp->idev->lock);
4765 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4766 		write_unlock_bh(&ifp->idev->lock);
4767 
4768 		if (action != CLEANUP_PREFIX_RT_NOP) {
4769 			cleanup_prefix_route(ifp, rt_expires,
4770 				action == CLEANUP_PREFIX_RT_DEL, false);
4771 		}
4772 	}
4773 
4774 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4775 		if (was_managetempaddr &&
4776 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4777 			cfg->valid_lft = 0;
4778 			cfg->preferred_lft = 0;
4779 		}
4780 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4781 				 cfg->preferred_lft, !was_managetempaddr,
4782 				 jiffies);
4783 	}
4784 
4785 	addrconf_verify_rtnl();
4786 
4787 	return 0;
4788 }
4789 
4790 static int
4791 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4792 		  struct netlink_ext_ack *extack)
4793 {
4794 	struct net *net = sock_net(skb->sk);
4795 	struct ifaddrmsg *ifm;
4796 	struct nlattr *tb[IFA_MAX+1];
4797 	struct in6_addr *peer_pfx;
4798 	struct inet6_ifaddr *ifa;
4799 	struct net_device *dev;
4800 	struct inet6_dev *idev;
4801 	struct ifa6_config cfg;
4802 	int err;
4803 
4804 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4805 				     ifa_ipv6_policy, extack);
4806 	if (err < 0)
4807 		return err;
4808 
4809 	memset(&cfg, 0, sizeof(cfg));
4810 
4811 	ifm = nlmsg_data(nlh);
4812 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4813 	if (!cfg.pfx)
4814 		return -EINVAL;
4815 
4816 	cfg.peer_pfx = peer_pfx;
4817 	cfg.plen = ifm->ifa_prefixlen;
4818 	if (tb[IFA_RT_PRIORITY])
4819 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4820 
4821 	cfg.valid_lft = INFINITY_LIFE_TIME;
4822 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4823 
4824 	if (tb[IFA_CACHEINFO]) {
4825 		struct ifa_cacheinfo *ci;
4826 
4827 		ci = nla_data(tb[IFA_CACHEINFO]);
4828 		cfg.valid_lft = ci->ifa_valid;
4829 		cfg.preferred_lft = ci->ifa_prefered;
4830 	}
4831 
4832 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4833 	if (!dev)
4834 		return -ENODEV;
4835 
4836 	if (tb[IFA_FLAGS])
4837 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4838 	else
4839 		cfg.ifa_flags = ifm->ifa_flags;
4840 
4841 	/* We ignore other flags so far. */
4842 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4843 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4844 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4845 
4846 	idev = ipv6_find_idev(dev);
4847 	if (IS_ERR(idev))
4848 		return PTR_ERR(idev);
4849 
4850 	if (!ipv6_allow_optimistic_dad(net, idev))
4851 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4852 
4853 	if (cfg.ifa_flags & IFA_F_NODAD &&
4854 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4855 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4856 		return -EINVAL;
4857 	}
4858 
4859 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4860 	if (!ifa) {
4861 		/*
4862 		 * It would be best to check for !NLM_F_CREATE here but
4863 		 * userspace already relies on not having to provide this.
4864 		 */
4865 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4866 	}
4867 
4868 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4869 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4870 		err = -EEXIST;
4871 	else
4872 		err = inet6_addr_modify(ifa, &cfg);
4873 
4874 	in6_ifa_put(ifa);
4875 
4876 	return err;
4877 }
4878 
4879 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4880 			  u8 scope, int ifindex)
4881 {
4882 	struct ifaddrmsg *ifm;
4883 
4884 	ifm = nlmsg_data(nlh);
4885 	ifm->ifa_family = AF_INET6;
4886 	ifm->ifa_prefixlen = prefixlen;
4887 	ifm->ifa_flags = flags;
4888 	ifm->ifa_scope = scope;
4889 	ifm->ifa_index = ifindex;
4890 }
4891 
4892 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4893 			 unsigned long tstamp, u32 preferred, u32 valid)
4894 {
4895 	struct ifa_cacheinfo ci;
4896 
4897 	ci.cstamp = cstamp_delta(cstamp);
4898 	ci.tstamp = cstamp_delta(tstamp);
4899 	ci.ifa_prefered = preferred;
4900 	ci.ifa_valid = valid;
4901 
4902 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4903 }
4904 
4905 static inline int rt_scope(int ifa_scope)
4906 {
4907 	if (ifa_scope & IFA_HOST)
4908 		return RT_SCOPE_HOST;
4909 	else if (ifa_scope & IFA_LINK)
4910 		return RT_SCOPE_LINK;
4911 	else if (ifa_scope & IFA_SITE)
4912 		return RT_SCOPE_SITE;
4913 	else
4914 		return RT_SCOPE_UNIVERSE;
4915 }
4916 
4917 static inline int inet6_ifaddr_msgsize(void)
4918 {
4919 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4920 	       + nla_total_size(16) /* IFA_LOCAL */
4921 	       + nla_total_size(16) /* IFA_ADDRESS */
4922 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4923 	       + nla_total_size(4)  /* IFA_FLAGS */
4924 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4925 }
4926 
4927 enum addr_type_t {
4928 	UNICAST_ADDR,
4929 	MULTICAST_ADDR,
4930 	ANYCAST_ADDR,
4931 };
4932 
4933 struct inet6_fill_args {
4934 	u32 portid;
4935 	u32 seq;
4936 	int event;
4937 	unsigned int flags;
4938 	int netnsid;
4939 	int ifindex;
4940 	enum addr_type_t type;
4941 };
4942 
4943 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4944 			     struct inet6_fill_args *args)
4945 {
4946 	struct nlmsghdr  *nlh;
4947 	u32 preferred, valid;
4948 
4949 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4950 			sizeof(struct ifaddrmsg), args->flags);
4951 	if (!nlh)
4952 		return -EMSGSIZE;
4953 
4954 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4955 		      ifa->idev->dev->ifindex);
4956 
4957 	if (args->netnsid >= 0 &&
4958 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4959 		goto error;
4960 
4961 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4962 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4963 		preferred = ifa->prefered_lft;
4964 		valid = ifa->valid_lft;
4965 		if (preferred != INFINITY_LIFE_TIME) {
4966 			long tval = (jiffies - ifa->tstamp)/HZ;
4967 			if (preferred > tval)
4968 				preferred -= tval;
4969 			else
4970 				preferred = 0;
4971 			if (valid != INFINITY_LIFE_TIME) {
4972 				if (valid > tval)
4973 					valid -= tval;
4974 				else
4975 					valid = 0;
4976 			}
4977 		}
4978 	} else {
4979 		preferred = INFINITY_LIFE_TIME;
4980 		valid = INFINITY_LIFE_TIME;
4981 	}
4982 
4983 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4984 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4985 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4986 			goto error;
4987 	} else
4988 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4989 			goto error;
4990 
4991 	if (ifa->rt_priority &&
4992 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4993 		goto error;
4994 
4995 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4996 		goto error;
4997 
4998 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4999 		goto error;
5000 
5001 	nlmsg_end(skb, nlh);
5002 	return 0;
5003 
5004 error:
5005 	nlmsg_cancel(skb, nlh);
5006 	return -EMSGSIZE;
5007 }
5008 
5009 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5010 			       struct inet6_fill_args *args)
5011 {
5012 	struct nlmsghdr  *nlh;
5013 	u8 scope = RT_SCOPE_UNIVERSE;
5014 	int ifindex = ifmca->idev->dev->ifindex;
5015 
5016 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5017 		scope = RT_SCOPE_SITE;
5018 
5019 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5020 			sizeof(struct ifaddrmsg), args->flags);
5021 	if (!nlh)
5022 		return -EMSGSIZE;
5023 
5024 	if (args->netnsid >= 0 &&
5025 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5026 		return -EMSGSIZE;
5027 
5028 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5029 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5030 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5031 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5032 		nlmsg_cancel(skb, nlh);
5033 		return -EMSGSIZE;
5034 	}
5035 
5036 	nlmsg_end(skb, nlh);
5037 	return 0;
5038 }
5039 
5040 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5041 			       struct inet6_fill_args *args)
5042 {
5043 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5044 	int ifindex = dev ? dev->ifindex : 1;
5045 	struct nlmsghdr  *nlh;
5046 	u8 scope = RT_SCOPE_UNIVERSE;
5047 
5048 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5049 		scope = RT_SCOPE_SITE;
5050 
5051 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5052 			sizeof(struct ifaddrmsg), args->flags);
5053 	if (!nlh)
5054 		return -EMSGSIZE;
5055 
5056 	if (args->netnsid >= 0 &&
5057 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5058 		return -EMSGSIZE;
5059 
5060 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5061 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5062 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5063 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5064 		nlmsg_cancel(skb, nlh);
5065 		return -EMSGSIZE;
5066 	}
5067 
5068 	nlmsg_end(skb, nlh);
5069 	return 0;
5070 }
5071 
5072 /* called with rcu_read_lock() */
5073 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5074 			  struct netlink_callback *cb, int s_ip_idx,
5075 			  struct inet6_fill_args *fillargs)
5076 {
5077 	struct ifmcaddr6 *ifmca;
5078 	struct ifacaddr6 *ifaca;
5079 	int ip_idx = 0;
5080 	int err = 1;
5081 
5082 	read_lock_bh(&idev->lock);
5083 	switch (fillargs->type) {
5084 	case UNICAST_ADDR: {
5085 		struct inet6_ifaddr *ifa;
5086 		fillargs->event = RTM_NEWADDR;
5087 
5088 		/* unicast address incl. temp addr */
5089 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5090 			if (ip_idx < s_ip_idx)
5091 				goto next;
5092 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5093 			if (err < 0)
5094 				break;
5095 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5096 next:
5097 			ip_idx++;
5098 		}
5099 		break;
5100 	}
5101 	case MULTICAST_ADDR:
5102 		fillargs->event = RTM_GETMULTICAST;
5103 
5104 		/* multicast address */
5105 		for (ifmca = idev->mc_list; ifmca;
5106 		     ifmca = ifmca->next, ip_idx++) {
5107 			if (ip_idx < s_ip_idx)
5108 				continue;
5109 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5110 			if (err < 0)
5111 				break;
5112 		}
5113 		break;
5114 	case ANYCAST_ADDR:
5115 		fillargs->event = RTM_GETANYCAST;
5116 		/* anycast address */
5117 		for (ifaca = idev->ac_list; ifaca;
5118 		     ifaca = ifaca->aca_next, ip_idx++) {
5119 			if (ip_idx < s_ip_idx)
5120 				continue;
5121 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5122 			if (err < 0)
5123 				break;
5124 		}
5125 		break;
5126 	default:
5127 		break;
5128 	}
5129 	read_unlock_bh(&idev->lock);
5130 	cb->args[2] = ip_idx;
5131 	return err;
5132 }
5133 
5134 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5135 				       struct inet6_fill_args *fillargs,
5136 				       struct net **tgt_net, struct sock *sk,
5137 				       struct netlink_callback *cb)
5138 {
5139 	struct netlink_ext_ack *extack = cb->extack;
5140 	struct nlattr *tb[IFA_MAX+1];
5141 	struct ifaddrmsg *ifm;
5142 	int err, i;
5143 
5144 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5145 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5146 		return -EINVAL;
5147 	}
5148 
5149 	ifm = nlmsg_data(nlh);
5150 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5151 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5152 		return -EINVAL;
5153 	}
5154 
5155 	fillargs->ifindex = ifm->ifa_index;
5156 	if (fillargs->ifindex) {
5157 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5158 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5159 	}
5160 
5161 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5162 					    ifa_ipv6_policy, extack);
5163 	if (err < 0)
5164 		return err;
5165 
5166 	for (i = 0; i <= IFA_MAX; ++i) {
5167 		if (!tb[i])
5168 			continue;
5169 
5170 		if (i == IFA_TARGET_NETNSID) {
5171 			struct net *net;
5172 
5173 			fillargs->netnsid = nla_get_s32(tb[i]);
5174 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5175 			if (IS_ERR(net)) {
5176 				fillargs->netnsid = -1;
5177 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5178 				return PTR_ERR(net);
5179 			}
5180 			*tgt_net = net;
5181 		} else {
5182 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5183 			return -EINVAL;
5184 		}
5185 	}
5186 
5187 	return 0;
5188 }
5189 
5190 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5191 			   enum addr_type_t type)
5192 {
5193 	const struct nlmsghdr *nlh = cb->nlh;
5194 	struct inet6_fill_args fillargs = {
5195 		.portid = NETLINK_CB(cb->skb).portid,
5196 		.seq = cb->nlh->nlmsg_seq,
5197 		.flags = NLM_F_MULTI,
5198 		.netnsid = -1,
5199 		.type = type,
5200 	};
5201 	struct net *net = sock_net(skb->sk);
5202 	struct net *tgt_net = net;
5203 	int idx, s_idx, s_ip_idx;
5204 	int h, s_h;
5205 	struct net_device *dev;
5206 	struct inet6_dev *idev;
5207 	struct hlist_head *head;
5208 	int err = 0;
5209 
5210 	s_h = cb->args[0];
5211 	s_idx = idx = cb->args[1];
5212 	s_ip_idx = cb->args[2];
5213 
5214 	if (cb->strict_check) {
5215 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5216 						  skb->sk, cb);
5217 		if (err < 0)
5218 			goto put_tgt_net;
5219 
5220 		err = 0;
5221 		if (fillargs.ifindex) {
5222 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5223 			if (!dev) {
5224 				err = -ENODEV;
5225 				goto put_tgt_net;
5226 			}
5227 			idev = __in6_dev_get(dev);
5228 			if (idev) {
5229 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5230 						     &fillargs);
5231 				if (err > 0)
5232 					err = 0;
5233 			}
5234 			goto put_tgt_net;
5235 		}
5236 	}
5237 
5238 	rcu_read_lock();
5239 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5240 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5241 		idx = 0;
5242 		head = &tgt_net->dev_index_head[h];
5243 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5244 			if (idx < s_idx)
5245 				goto cont;
5246 			if (h > s_h || idx > s_idx)
5247 				s_ip_idx = 0;
5248 			idev = __in6_dev_get(dev);
5249 			if (!idev)
5250 				goto cont;
5251 
5252 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5253 					   &fillargs) < 0)
5254 				goto done;
5255 cont:
5256 			idx++;
5257 		}
5258 	}
5259 done:
5260 	rcu_read_unlock();
5261 	cb->args[0] = h;
5262 	cb->args[1] = idx;
5263 put_tgt_net:
5264 	if (fillargs.netnsid >= 0)
5265 		put_net(tgt_net);
5266 
5267 	return skb->len ? : err;
5268 }
5269 
5270 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5271 {
5272 	enum addr_type_t type = UNICAST_ADDR;
5273 
5274 	return inet6_dump_addr(skb, cb, type);
5275 }
5276 
5277 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5278 {
5279 	enum addr_type_t type = MULTICAST_ADDR;
5280 
5281 	return inet6_dump_addr(skb, cb, type);
5282 }
5283 
5284 
5285 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5286 {
5287 	enum addr_type_t type = ANYCAST_ADDR;
5288 
5289 	return inet6_dump_addr(skb, cb, type);
5290 }
5291 
5292 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5293 				       const struct nlmsghdr *nlh,
5294 				       struct nlattr **tb,
5295 				       struct netlink_ext_ack *extack)
5296 {
5297 	struct ifaddrmsg *ifm;
5298 	int i, err;
5299 
5300 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5301 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5302 		return -EINVAL;
5303 	}
5304 
5305 	if (!netlink_strict_get_check(skb))
5306 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5307 					      ifa_ipv6_policy, extack);
5308 
5309 	ifm = nlmsg_data(nlh);
5310 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5311 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5312 		return -EINVAL;
5313 	}
5314 
5315 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5316 					    ifa_ipv6_policy, extack);
5317 	if (err)
5318 		return err;
5319 
5320 	for (i = 0; i <= IFA_MAX; i++) {
5321 		if (!tb[i])
5322 			continue;
5323 
5324 		switch (i) {
5325 		case IFA_TARGET_NETNSID:
5326 		case IFA_ADDRESS:
5327 		case IFA_LOCAL:
5328 			break;
5329 		default:
5330 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5331 			return -EINVAL;
5332 		}
5333 	}
5334 
5335 	return 0;
5336 }
5337 
5338 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5339 			     struct netlink_ext_ack *extack)
5340 {
5341 	struct net *net = sock_net(in_skb->sk);
5342 	struct inet6_fill_args fillargs = {
5343 		.portid = NETLINK_CB(in_skb).portid,
5344 		.seq = nlh->nlmsg_seq,
5345 		.event = RTM_NEWADDR,
5346 		.flags = 0,
5347 		.netnsid = -1,
5348 	};
5349 	struct net *tgt_net = net;
5350 	struct ifaddrmsg *ifm;
5351 	struct nlattr *tb[IFA_MAX+1];
5352 	struct in6_addr *addr = NULL, *peer;
5353 	struct net_device *dev = NULL;
5354 	struct inet6_ifaddr *ifa;
5355 	struct sk_buff *skb;
5356 	int err;
5357 
5358 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5359 	if (err < 0)
5360 		return err;
5361 
5362 	if (tb[IFA_TARGET_NETNSID]) {
5363 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5364 
5365 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5366 						  fillargs.netnsid);
5367 		if (IS_ERR(tgt_net))
5368 			return PTR_ERR(tgt_net);
5369 	}
5370 
5371 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5372 	if (!addr)
5373 		return -EINVAL;
5374 
5375 	ifm = nlmsg_data(nlh);
5376 	if (ifm->ifa_index)
5377 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5378 
5379 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5380 	if (!ifa) {
5381 		err = -EADDRNOTAVAIL;
5382 		goto errout;
5383 	}
5384 
5385 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5386 	if (!skb) {
5387 		err = -ENOBUFS;
5388 		goto errout_ifa;
5389 	}
5390 
5391 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5392 	if (err < 0) {
5393 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5394 		WARN_ON(err == -EMSGSIZE);
5395 		kfree_skb(skb);
5396 		goto errout_ifa;
5397 	}
5398 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5399 errout_ifa:
5400 	in6_ifa_put(ifa);
5401 errout:
5402 	if (dev)
5403 		dev_put(dev);
5404 	if (fillargs.netnsid >= 0)
5405 		put_net(tgt_net);
5406 
5407 	return err;
5408 }
5409 
5410 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5411 {
5412 	struct sk_buff *skb;
5413 	struct net *net = dev_net(ifa->idev->dev);
5414 	struct inet6_fill_args fillargs = {
5415 		.portid = 0,
5416 		.seq = 0,
5417 		.event = event,
5418 		.flags = 0,
5419 		.netnsid = -1,
5420 	};
5421 	int err = -ENOBUFS;
5422 
5423 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5424 	if (!skb)
5425 		goto errout;
5426 
5427 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5428 	if (err < 0) {
5429 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5430 		WARN_ON(err == -EMSGSIZE);
5431 		kfree_skb(skb);
5432 		goto errout;
5433 	}
5434 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5435 	return;
5436 errout:
5437 	if (err < 0)
5438 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5439 }
5440 
5441 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5442 				__s32 *array, int bytes)
5443 {
5444 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5445 
5446 	memset(array, 0, bytes);
5447 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5448 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5449 	array[DEVCONF_MTU6] = cnf->mtu6;
5450 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5451 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5452 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5453 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5454 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5455 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5456 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5457 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5458 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5459 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5460 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5461 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5462 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5463 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5464 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5465 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5466 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5467 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5468 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5469 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5470 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5471 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5472 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5473 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5474 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5475 #ifdef CONFIG_IPV6_ROUTER_PREF
5476 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5477 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5478 		jiffies_to_msecs(cnf->rtr_probe_interval);
5479 #ifdef CONFIG_IPV6_ROUTE_INFO
5480 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5481 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5482 #endif
5483 #endif
5484 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5485 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5486 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5487 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5488 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5489 #endif
5490 #ifdef CONFIG_IPV6_MROUTE
5491 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5492 #endif
5493 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5494 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5495 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5496 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5497 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5498 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5499 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5500 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5501 	/* we omit DEVCONF_STABLE_SECRET for now */
5502 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5503 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5504 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5505 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5506 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5507 #ifdef CONFIG_IPV6_SEG6_HMAC
5508 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5509 #endif
5510 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5511 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5512 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5513 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5514 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5515 }
5516 
5517 static inline size_t inet6_ifla6_size(void)
5518 {
5519 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5520 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5521 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5522 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5523 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5524 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5525 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5526 	     + 0;
5527 }
5528 
5529 static inline size_t inet6_if_nlmsg_size(void)
5530 {
5531 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5532 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5533 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5534 	       + nla_total_size(4) /* IFLA_MTU */
5535 	       + nla_total_size(4) /* IFLA_LINK */
5536 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5537 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5538 }
5539 
5540 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5541 					int bytes)
5542 {
5543 	int i;
5544 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5545 	BUG_ON(pad < 0);
5546 
5547 	/* Use put_unaligned() because stats may not be aligned for u64. */
5548 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5549 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5550 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5551 
5552 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5553 }
5554 
5555 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5556 					int bytes, size_t syncpoff)
5557 {
5558 	int i, c;
5559 	u64 buff[IPSTATS_MIB_MAX];
5560 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5561 
5562 	BUG_ON(pad < 0);
5563 
5564 	memset(buff, 0, sizeof(buff));
5565 	buff[0] = IPSTATS_MIB_MAX;
5566 
5567 	for_each_possible_cpu(c) {
5568 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5569 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5570 	}
5571 
5572 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5573 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5574 }
5575 
5576 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5577 			     int bytes)
5578 {
5579 	switch (attrtype) {
5580 	case IFLA_INET6_STATS:
5581 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5582 				     offsetof(struct ipstats_mib, syncp));
5583 		break;
5584 	case IFLA_INET6_ICMP6STATS:
5585 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5586 		break;
5587 	}
5588 }
5589 
5590 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5591 				  u32 ext_filter_mask)
5592 {
5593 	struct nlattr *nla;
5594 	struct ifla_cacheinfo ci;
5595 
5596 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5597 		goto nla_put_failure;
5598 	ci.max_reasm_len = IPV6_MAXPLEN;
5599 	ci.tstamp = cstamp_delta(idev->tstamp);
5600 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5601 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5602 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5603 		goto nla_put_failure;
5604 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5605 	if (!nla)
5606 		goto nla_put_failure;
5607 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5608 
5609 	/* XXX - MC not implemented */
5610 
5611 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5612 		return 0;
5613 
5614 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5615 	if (!nla)
5616 		goto nla_put_failure;
5617 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5618 
5619 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5620 	if (!nla)
5621 		goto nla_put_failure;
5622 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5623 
5624 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5625 	if (!nla)
5626 		goto nla_put_failure;
5627 	read_lock_bh(&idev->lock);
5628 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5629 	read_unlock_bh(&idev->lock);
5630 
5631 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5632 		goto nla_put_failure;
5633 
5634 	return 0;
5635 
5636 nla_put_failure:
5637 	return -EMSGSIZE;
5638 }
5639 
5640 static size_t inet6_get_link_af_size(const struct net_device *dev,
5641 				     u32 ext_filter_mask)
5642 {
5643 	if (!__in6_dev_get(dev))
5644 		return 0;
5645 
5646 	return inet6_ifla6_size();
5647 }
5648 
5649 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5650 			      u32 ext_filter_mask)
5651 {
5652 	struct inet6_dev *idev = __in6_dev_get(dev);
5653 
5654 	if (!idev)
5655 		return -ENODATA;
5656 
5657 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5658 		return -EMSGSIZE;
5659 
5660 	return 0;
5661 }
5662 
5663 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5664 {
5665 	struct inet6_ifaddr *ifp;
5666 	struct net_device *dev = idev->dev;
5667 	bool clear_token, update_rs = false;
5668 	struct in6_addr ll_addr;
5669 
5670 	ASSERT_RTNL();
5671 
5672 	if (!token)
5673 		return -EINVAL;
5674 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5675 		return -EINVAL;
5676 	if (!ipv6_accept_ra(idev))
5677 		return -EINVAL;
5678 	if (idev->cnf.rtr_solicits == 0)
5679 		return -EINVAL;
5680 
5681 	write_lock_bh(&idev->lock);
5682 
5683 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5684 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5685 
5686 	write_unlock_bh(&idev->lock);
5687 
5688 	clear_token = ipv6_addr_any(token);
5689 	if (clear_token)
5690 		goto update_lft;
5691 
5692 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5693 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5694 			     IFA_F_OPTIMISTIC)) {
5695 		/* If we're not ready, then normal ifup will take care
5696 		 * of this. Otherwise, we need to request our rs here.
5697 		 */
5698 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5699 		update_rs = true;
5700 	}
5701 
5702 update_lft:
5703 	write_lock_bh(&idev->lock);
5704 
5705 	if (update_rs) {
5706 		idev->if_flags |= IF_RS_SENT;
5707 		idev->rs_interval = rfc3315_s14_backoff_init(
5708 			idev->cnf.rtr_solicit_interval);
5709 		idev->rs_probes = 1;
5710 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5711 	}
5712 
5713 	/* Well, that's kinda nasty ... */
5714 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5715 		spin_lock(&ifp->lock);
5716 		if (ifp->tokenized) {
5717 			ifp->valid_lft = 0;
5718 			ifp->prefered_lft = 0;
5719 		}
5720 		spin_unlock(&ifp->lock);
5721 	}
5722 
5723 	write_unlock_bh(&idev->lock);
5724 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5725 	addrconf_verify_rtnl();
5726 	return 0;
5727 }
5728 
5729 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5730 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5731 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5732 };
5733 
5734 static int check_addr_gen_mode(int mode)
5735 {
5736 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5737 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5738 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5739 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5740 		return -EINVAL;
5741 	return 1;
5742 }
5743 
5744 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5745 				int mode)
5746 {
5747 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5748 	    !idev->cnf.stable_secret.initialized &&
5749 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5750 		return -EINVAL;
5751 	return 1;
5752 }
5753 
5754 static int inet6_validate_link_af(const struct net_device *dev,
5755 				  const struct nlattr *nla)
5756 {
5757 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5758 	struct inet6_dev *idev = NULL;
5759 	int err;
5760 
5761 	if (dev) {
5762 		idev = __in6_dev_get(dev);
5763 		if (!idev)
5764 			return -EAFNOSUPPORT;
5765 	}
5766 
5767 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5768 					  inet6_af_policy, NULL);
5769 	if (err)
5770 		return err;
5771 
5772 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5773 		return -EINVAL;
5774 
5775 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5776 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5777 
5778 		if (check_addr_gen_mode(mode) < 0)
5779 			return -EINVAL;
5780 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5781 			return -EINVAL;
5782 	}
5783 
5784 	return 0;
5785 }
5786 
5787 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5788 {
5789 	struct inet6_dev *idev = __in6_dev_get(dev);
5790 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5791 	int err;
5792 
5793 	if (!idev)
5794 		return -EAFNOSUPPORT;
5795 
5796 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5797 		BUG();
5798 
5799 	if (tb[IFLA_INET6_TOKEN]) {
5800 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5801 		if (err)
5802 			return err;
5803 	}
5804 
5805 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5806 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5807 
5808 		idev->cnf.addr_gen_mode = mode;
5809 	}
5810 
5811 	return 0;
5812 }
5813 
5814 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5815 			     u32 portid, u32 seq, int event, unsigned int flags)
5816 {
5817 	struct net_device *dev = idev->dev;
5818 	struct ifinfomsg *hdr;
5819 	struct nlmsghdr *nlh;
5820 	void *protoinfo;
5821 
5822 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5823 	if (!nlh)
5824 		return -EMSGSIZE;
5825 
5826 	hdr = nlmsg_data(nlh);
5827 	hdr->ifi_family = AF_INET6;
5828 	hdr->__ifi_pad = 0;
5829 	hdr->ifi_type = dev->type;
5830 	hdr->ifi_index = dev->ifindex;
5831 	hdr->ifi_flags = dev_get_flags(dev);
5832 	hdr->ifi_change = 0;
5833 
5834 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5835 	    (dev->addr_len &&
5836 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5837 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5838 	    (dev->ifindex != dev_get_iflink(dev) &&
5839 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5840 	    nla_put_u8(skb, IFLA_OPERSTATE,
5841 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5842 		goto nla_put_failure;
5843 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5844 	if (!protoinfo)
5845 		goto nla_put_failure;
5846 
5847 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5848 		goto nla_put_failure;
5849 
5850 	nla_nest_end(skb, protoinfo);
5851 	nlmsg_end(skb, nlh);
5852 	return 0;
5853 
5854 nla_put_failure:
5855 	nlmsg_cancel(skb, nlh);
5856 	return -EMSGSIZE;
5857 }
5858 
5859 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5860 				   struct netlink_ext_ack *extack)
5861 {
5862 	struct ifinfomsg *ifm;
5863 
5864 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5865 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5866 		return -EINVAL;
5867 	}
5868 
5869 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5870 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5871 		return -EINVAL;
5872 	}
5873 
5874 	ifm = nlmsg_data(nlh);
5875 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5876 	    ifm->ifi_change || ifm->ifi_index) {
5877 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5878 		return -EINVAL;
5879 	}
5880 
5881 	return 0;
5882 }
5883 
5884 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5885 {
5886 	struct net *net = sock_net(skb->sk);
5887 	int h, s_h;
5888 	int idx = 0, s_idx;
5889 	struct net_device *dev;
5890 	struct inet6_dev *idev;
5891 	struct hlist_head *head;
5892 
5893 	/* only requests using strict checking can pass data to
5894 	 * influence the dump
5895 	 */
5896 	if (cb->strict_check) {
5897 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5898 
5899 		if (err < 0)
5900 			return err;
5901 	}
5902 
5903 	s_h = cb->args[0];
5904 	s_idx = cb->args[1];
5905 
5906 	rcu_read_lock();
5907 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5908 		idx = 0;
5909 		head = &net->dev_index_head[h];
5910 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5911 			if (idx < s_idx)
5912 				goto cont;
5913 			idev = __in6_dev_get(dev);
5914 			if (!idev)
5915 				goto cont;
5916 			if (inet6_fill_ifinfo(skb, idev,
5917 					      NETLINK_CB(cb->skb).portid,
5918 					      cb->nlh->nlmsg_seq,
5919 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5920 				goto out;
5921 cont:
5922 			idx++;
5923 		}
5924 	}
5925 out:
5926 	rcu_read_unlock();
5927 	cb->args[1] = idx;
5928 	cb->args[0] = h;
5929 
5930 	return skb->len;
5931 }
5932 
5933 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5934 {
5935 	struct sk_buff *skb;
5936 	struct net *net = dev_net(idev->dev);
5937 	int err = -ENOBUFS;
5938 
5939 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5940 	if (!skb)
5941 		goto errout;
5942 
5943 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5944 	if (err < 0) {
5945 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5946 		WARN_ON(err == -EMSGSIZE);
5947 		kfree_skb(skb);
5948 		goto errout;
5949 	}
5950 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5951 	return;
5952 errout:
5953 	if (err < 0)
5954 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5955 }
5956 
5957 static inline size_t inet6_prefix_nlmsg_size(void)
5958 {
5959 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5960 	       + nla_total_size(sizeof(struct in6_addr))
5961 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5962 }
5963 
5964 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5965 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5966 			     int event, unsigned int flags)
5967 {
5968 	struct prefixmsg *pmsg;
5969 	struct nlmsghdr *nlh;
5970 	struct prefix_cacheinfo	ci;
5971 
5972 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5973 	if (!nlh)
5974 		return -EMSGSIZE;
5975 
5976 	pmsg = nlmsg_data(nlh);
5977 	pmsg->prefix_family = AF_INET6;
5978 	pmsg->prefix_pad1 = 0;
5979 	pmsg->prefix_pad2 = 0;
5980 	pmsg->prefix_ifindex = idev->dev->ifindex;
5981 	pmsg->prefix_len = pinfo->prefix_len;
5982 	pmsg->prefix_type = pinfo->type;
5983 	pmsg->prefix_pad3 = 0;
5984 	pmsg->prefix_flags = 0;
5985 	if (pinfo->onlink)
5986 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5987 	if (pinfo->autoconf)
5988 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5989 
5990 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5991 		goto nla_put_failure;
5992 	ci.preferred_time = ntohl(pinfo->prefered);
5993 	ci.valid_time = ntohl(pinfo->valid);
5994 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5995 		goto nla_put_failure;
5996 	nlmsg_end(skb, nlh);
5997 	return 0;
5998 
5999 nla_put_failure:
6000 	nlmsg_cancel(skb, nlh);
6001 	return -EMSGSIZE;
6002 }
6003 
6004 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6005 			 struct prefix_info *pinfo)
6006 {
6007 	struct sk_buff *skb;
6008 	struct net *net = dev_net(idev->dev);
6009 	int err = -ENOBUFS;
6010 
6011 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6012 	if (!skb)
6013 		goto errout;
6014 
6015 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6016 	if (err < 0) {
6017 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6018 		WARN_ON(err == -EMSGSIZE);
6019 		kfree_skb(skb);
6020 		goto errout;
6021 	}
6022 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6023 	return;
6024 errout:
6025 	if (err < 0)
6026 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6027 }
6028 
6029 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6030 {
6031 	struct net *net = dev_net(ifp->idev->dev);
6032 
6033 	if (event)
6034 		ASSERT_RTNL();
6035 
6036 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6037 
6038 	switch (event) {
6039 	case RTM_NEWADDR:
6040 		/*
6041 		 * If the address was optimistic we inserted the route at the
6042 		 * start of our DAD process, so we don't need to do it again.
6043 		 * If the device was taken down in the middle of the DAD
6044 		 * cycle there is a race where we could get here without a
6045 		 * host route, so nothing to insert. That will be fixed when
6046 		 * the device is brought up.
6047 		 */
6048 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6049 			ip6_ins_rt(net, ifp->rt);
6050 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6051 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6052 				&ifp->addr, ifp->idev->dev->name);
6053 		}
6054 
6055 		if (ifp->idev->cnf.forwarding)
6056 			addrconf_join_anycast(ifp);
6057 		if (!ipv6_addr_any(&ifp->peer_addr))
6058 			addrconf_prefix_route(&ifp->peer_addr, 128,
6059 					      ifp->rt_priority, ifp->idev->dev,
6060 					      0, 0, GFP_ATOMIC);
6061 		break;
6062 	case RTM_DELADDR:
6063 		if (ifp->idev->cnf.forwarding)
6064 			addrconf_leave_anycast(ifp);
6065 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6066 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6067 			struct fib6_info *rt;
6068 
6069 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6070 						       ifp->idev->dev, 0, 0,
6071 						       false);
6072 			if (rt)
6073 				ip6_del_rt(net, rt, false);
6074 		}
6075 		if (ifp->rt) {
6076 			ip6_del_rt(net, ifp->rt, false);
6077 			ifp->rt = NULL;
6078 		}
6079 		rt_genid_bump_ipv6(net);
6080 		break;
6081 	}
6082 	atomic_inc(&net->ipv6.dev_addr_genid);
6083 }
6084 
6085 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6086 {
6087 	rcu_read_lock_bh();
6088 	if (likely(ifp->idev->dead == 0))
6089 		__ipv6_ifa_notify(event, ifp);
6090 	rcu_read_unlock_bh();
6091 }
6092 
6093 #ifdef CONFIG_SYSCTL
6094 
6095 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6096 		void *buffer, size_t *lenp, loff_t *ppos)
6097 {
6098 	int *valp = ctl->data;
6099 	int val = *valp;
6100 	loff_t pos = *ppos;
6101 	struct ctl_table lctl;
6102 	int ret;
6103 
6104 	/*
6105 	 * ctl->data points to idev->cnf.forwarding, we should
6106 	 * not modify it until we get the rtnl lock.
6107 	 */
6108 	lctl = *ctl;
6109 	lctl.data = &val;
6110 
6111 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6112 
6113 	if (write)
6114 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6115 	if (ret)
6116 		*ppos = pos;
6117 	return ret;
6118 }
6119 
6120 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6121 		void *buffer, size_t *lenp, loff_t *ppos)
6122 {
6123 	struct inet6_dev *idev = ctl->extra1;
6124 	int min_mtu = IPV6_MIN_MTU;
6125 	struct ctl_table lctl;
6126 
6127 	lctl = *ctl;
6128 	lctl.extra1 = &min_mtu;
6129 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6130 
6131 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6132 }
6133 
6134 static void dev_disable_change(struct inet6_dev *idev)
6135 {
6136 	struct netdev_notifier_info info;
6137 
6138 	if (!idev || !idev->dev)
6139 		return;
6140 
6141 	netdev_notifier_info_init(&info, idev->dev);
6142 	if (idev->cnf.disable_ipv6)
6143 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6144 	else
6145 		addrconf_notify(NULL, NETDEV_UP, &info);
6146 }
6147 
6148 static void addrconf_disable_change(struct net *net, __s32 newf)
6149 {
6150 	struct net_device *dev;
6151 	struct inet6_dev *idev;
6152 
6153 	for_each_netdev(net, dev) {
6154 		idev = __in6_dev_get(dev);
6155 		if (idev) {
6156 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6157 			idev->cnf.disable_ipv6 = newf;
6158 			if (changed)
6159 				dev_disable_change(idev);
6160 		}
6161 	}
6162 }
6163 
6164 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6165 {
6166 	struct net *net;
6167 	int old;
6168 
6169 	if (!rtnl_trylock())
6170 		return restart_syscall();
6171 
6172 	net = (struct net *)table->extra2;
6173 	old = *p;
6174 	*p = newf;
6175 
6176 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6177 		rtnl_unlock();
6178 		return 0;
6179 	}
6180 
6181 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6182 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6183 		addrconf_disable_change(net, newf);
6184 	} else if ((!newf) ^ (!old))
6185 		dev_disable_change((struct inet6_dev *)table->extra1);
6186 
6187 	rtnl_unlock();
6188 	return 0;
6189 }
6190 
6191 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6192 		void *buffer, size_t *lenp, loff_t *ppos)
6193 {
6194 	int *valp = ctl->data;
6195 	int val = *valp;
6196 	loff_t pos = *ppos;
6197 	struct ctl_table lctl;
6198 	int ret;
6199 
6200 	/*
6201 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6202 	 * not modify it until we get the rtnl lock.
6203 	 */
6204 	lctl = *ctl;
6205 	lctl.data = &val;
6206 
6207 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6208 
6209 	if (write)
6210 		ret = addrconf_disable_ipv6(ctl, valp, val);
6211 	if (ret)
6212 		*ppos = pos;
6213 	return ret;
6214 }
6215 
6216 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6217 		void *buffer, size_t *lenp, loff_t *ppos)
6218 {
6219 	int *valp = ctl->data;
6220 	int ret;
6221 	int old, new;
6222 
6223 	old = *valp;
6224 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6225 	new = *valp;
6226 
6227 	if (write && old != new) {
6228 		struct net *net = ctl->extra2;
6229 
6230 		if (!rtnl_trylock())
6231 			return restart_syscall();
6232 
6233 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6234 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6235 						     NETCONFA_PROXY_NEIGH,
6236 						     NETCONFA_IFINDEX_DEFAULT,
6237 						     net->ipv6.devconf_dflt);
6238 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6239 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6240 						     NETCONFA_PROXY_NEIGH,
6241 						     NETCONFA_IFINDEX_ALL,
6242 						     net->ipv6.devconf_all);
6243 		else {
6244 			struct inet6_dev *idev = ctl->extra1;
6245 
6246 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6247 						     NETCONFA_PROXY_NEIGH,
6248 						     idev->dev->ifindex,
6249 						     &idev->cnf);
6250 		}
6251 		rtnl_unlock();
6252 	}
6253 
6254 	return ret;
6255 }
6256 
6257 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6258 					 void *buffer, size_t *lenp,
6259 					 loff_t *ppos)
6260 {
6261 	int ret = 0;
6262 	u32 new_val;
6263 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6264 	struct net *net = (struct net *)ctl->extra2;
6265 	struct ctl_table tmp = {
6266 		.data = &new_val,
6267 		.maxlen = sizeof(new_val),
6268 		.mode = ctl->mode,
6269 	};
6270 
6271 	if (!rtnl_trylock())
6272 		return restart_syscall();
6273 
6274 	new_val = *((u32 *)ctl->data);
6275 
6276 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6277 	if (ret != 0)
6278 		goto out;
6279 
6280 	if (write) {
6281 		if (check_addr_gen_mode(new_val) < 0) {
6282 			ret = -EINVAL;
6283 			goto out;
6284 		}
6285 
6286 		if (idev) {
6287 			if (check_stable_privacy(idev, net, new_val) < 0) {
6288 				ret = -EINVAL;
6289 				goto out;
6290 			}
6291 
6292 			if (idev->cnf.addr_gen_mode != new_val) {
6293 				idev->cnf.addr_gen_mode = new_val;
6294 				addrconf_dev_config(idev->dev);
6295 			}
6296 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6297 			struct net_device *dev;
6298 
6299 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6300 			for_each_netdev(net, dev) {
6301 				idev = __in6_dev_get(dev);
6302 				if (idev &&
6303 				    idev->cnf.addr_gen_mode != new_val) {
6304 					idev->cnf.addr_gen_mode = new_val;
6305 					addrconf_dev_config(idev->dev);
6306 				}
6307 			}
6308 		}
6309 
6310 		*((u32 *)ctl->data) = new_val;
6311 	}
6312 
6313 out:
6314 	rtnl_unlock();
6315 
6316 	return ret;
6317 }
6318 
6319 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6320 					 void *buffer, size_t *lenp,
6321 					 loff_t *ppos)
6322 {
6323 	int err;
6324 	struct in6_addr addr;
6325 	char str[IPV6_MAX_STRLEN];
6326 	struct ctl_table lctl = *ctl;
6327 	struct net *net = ctl->extra2;
6328 	struct ipv6_stable_secret *secret = ctl->data;
6329 
6330 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6331 		return -EIO;
6332 
6333 	lctl.maxlen = IPV6_MAX_STRLEN;
6334 	lctl.data = str;
6335 
6336 	if (!rtnl_trylock())
6337 		return restart_syscall();
6338 
6339 	if (!write && !secret->initialized) {
6340 		err = -EIO;
6341 		goto out;
6342 	}
6343 
6344 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6345 	if (err >= sizeof(str)) {
6346 		err = -EIO;
6347 		goto out;
6348 	}
6349 
6350 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6351 	if (err || !write)
6352 		goto out;
6353 
6354 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6355 		err = -EIO;
6356 		goto out;
6357 	}
6358 
6359 	secret->initialized = true;
6360 	secret->secret = addr;
6361 
6362 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6363 		struct net_device *dev;
6364 
6365 		for_each_netdev(net, dev) {
6366 			struct inet6_dev *idev = __in6_dev_get(dev);
6367 
6368 			if (idev) {
6369 				idev->cnf.addr_gen_mode =
6370 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6371 			}
6372 		}
6373 	} else {
6374 		struct inet6_dev *idev = ctl->extra1;
6375 
6376 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6377 	}
6378 
6379 out:
6380 	rtnl_unlock();
6381 
6382 	return err;
6383 }
6384 
6385 static
6386 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6387 						int write, void *buffer,
6388 						size_t *lenp,
6389 						loff_t *ppos)
6390 {
6391 	int *valp = ctl->data;
6392 	int val = *valp;
6393 	loff_t pos = *ppos;
6394 	struct ctl_table lctl;
6395 	int ret;
6396 
6397 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6398 	 * we should not modify it until we get the rtnl lock.
6399 	 */
6400 	lctl = *ctl;
6401 	lctl.data = &val;
6402 
6403 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6404 
6405 	if (write)
6406 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6407 	if (ret)
6408 		*ppos = pos;
6409 	return ret;
6410 }
6411 
6412 static
6413 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6414 {
6415 	if (rt) {
6416 		if (action)
6417 			rt->dst.flags |= DST_NOPOLICY;
6418 		else
6419 			rt->dst.flags &= ~DST_NOPOLICY;
6420 	}
6421 }
6422 
6423 static
6424 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6425 {
6426 	struct inet6_ifaddr *ifa;
6427 
6428 	read_lock_bh(&idev->lock);
6429 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6430 		spin_lock(&ifa->lock);
6431 		if (ifa->rt) {
6432 			/* host routes only use builtin fib6_nh */
6433 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6434 			int cpu;
6435 
6436 			rcu_read_lock();
6437 			ifa->rt->dst_nopolicy = val ? true : false;
6438 			if (nh->rt6i_pcpu) {
6439 				for_each_possible_cpu(cpu) {
6440 					struct rt6_info **rtp;
6441 
6442 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6443 					addrconf_set_nopolicy(*rtp, val);
6444 				}
6445 			}
6446 			rcu_read_unlock();
6447 		}
6448 		spin_unlock(&ifa->lock);
6449 	}
6450 	read_unlock_bh(&idev->lock);
6451 }
6452 
6453 static
6454 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6455 {
6456 	struct inet6_dev *idev;
6457 	struct net *net;
6458 
6459 	if (!rtnl_trylock())
6460 		return restart_syscall();
6461 
6462 	*valp = val;
6463 
6464 	net = (struct net *)ctl->extra2;
6465 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6466 		rtnl_unlock();
6467 		return 0;
6468 	}
6469 
6470 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6471 		struct net_device *dev;
6472 
6473 		for_each_netdev(net, dev) {
6474 			idev = __in6_dev_get(dev);
6475 			if (idev)
6476 				addrconf_disable_policy_idev(idev, val);
6477 		}
6478 	} else {
6479 		idev = (struct inet6_dev *)ctl->extra1;
6480 		addrconf_disable_policy_idev(idev, val);
6481 	}
6482 
6483 	rtnl_unlock();
6484 	return 0;
6485 }
6486 
6487 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6488 				   void *buffer, size_t *lenp, loff_t *ppos)
6489 {
6490 	int *valp = ctl->data;
6491 	int val = *valp;
6492 	loff_t pos = *ppos;
6493 	struct ctl_table lctl;
6494 	int ret;
6495 
6496 	lctl = *ctl;
6497 	lctl.data = &val;
6498 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6499 
6500 	if (write && (*valp != val))
6501 		ret = addrconf_disable_policy(ctl, valp, val);
6502 
6503 	if (ret)
6504 		*ppos = pos;
6505 
6506 	return ret;
6507 }
6508 
6509 static int minus_one = -1;
6510 static const int two_five_five = 255;
6511 
6512 static const struct ctl_table addrconf_sysctl[] = {
6513 	{
6514 		.procname	= "forwarding",
6515 		.data		= &ipv6_devconf.forwarding,
6516 		.maxlen		= sizeof(int),
6517 		.mode		= 0644,
6518 		.proc_handler	= addrconf_sysctl_forward,
6519 	},
6520 	{
6521 		.procname	= "hop_limit",
6522 		.data		= &ipv6_devconf.hop_limit,
6523 		.maxlen		= sizeof(int),
6524 		.mode		= 0644,
6525 		.proc_handler	= proc_dointvec_minmax,
6526 		.extra1		= (void *)SYSCTL_ONE,
6527 		.extra2		= (void *)&two_five_five,
6528 	},
6529 	{
6530 		.procname	= "mtu",
6531 		.data		= &ipv6_devconf.mtu6,
6532 		.maxlen		= sizeof(int),
6533 		.mode		= 0644,
6534 		.proc_handler	= addrconf_sysctl_mtu,
6535 	},
6536 	{
6537 		.procname	= "accept_ra",
6538 		.data		= &ipv6_devconf.accept_ra,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= proc_dointvec,
6542 	},
6543 	{
6544 		.procname	= "accept_redirects",
6545 		.data		= &ipv6_devconf.accept_redirects,
6546 		.maxlen		= sizeof(int),
6547 		.mode		= 0644,
6548 		.proc_handler	= proc_dointvec,
6549 	},
6550 	{
6551 		.procname	= "autoconf",
6552 		.data		= &ipv6_devconf.autoconf,
6553 		.maxlen		= sizeof(int),
6554 		.mode		= 0644,
6555 		.proc_handler	= proc_dointvec,
6556 	},
6557 	{
6558 		.procname	= "dad_transmits",
6559 		.data		= &ipv6_devconf.dad_transmits,
6560 		.maxlen		= sizeof(int),
6561 		.mode		= 0644,
6562 		.proc_handler	= proc_dointvec,
6563 	},
6564 	{
6565 		.procname	= "router_solicitations",
6566 		.data		= &ipv6_devconf.rtr_solicits,
6567 		.maxlen		= sizeof(int),
6568 		.mode		= 0644,
6569 		.proc_handler	= proc_dointvec_minmax,
6570 		.extra1		= &minus_one,
6571 	},
6572 	{
6573 		.procname	= "router_solicitation_interval",
6574 		.data		= &ipv6_devconf.rtr_solicit_interval,
6575 		.maxlen		= sizeof(int),
6576 		.mode		= 0644,
6577 		.proc_handler	= proc_dointvec_jiffies,
6578 	},
6579 	{
6580 		.procname	= "router_solicitation_max_interval",
6581 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6582 		.maxlen		= sizeof(int),
6583 		.mode		= 0644,
6584 		.proc_handler	= proc_dointvec_jiffies,
6585 	},
6586 	{
6587 		.procname	= "router_solicitation_delay",
6588 		.data		= &ipv6_devconf.rtr_solicit_delay,
6589 		.maxlen		= sizeof(int),
6590 		.mode		= 0644,
6591 		.proc_handler	= proc_dointvec_jiffies,
6592 	},
6593 	{
6594 		.procname	= "force_mld_version",
6595 		.data		= &ipv6_devconf.force_mld_version,
6596 		.maxlen		= sizeof(int),
6597 		.mode		= 0644,
6598 		.proc_handler	= proc_dointvec,
6599 	},
6600 	{
6601 		.procname	= "mldv1_unsolicited_report_interval",
6602 		.data		=
6603 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6604 		.maxlen		= sizeof(int),
6605 		.mode		= 0644,
6606 		.proc_handler	= proc_dointvec_ms_jiffies,
6607 	},
6608 	{
6609 		.procname	= "mldv2_unsolicited_report_interval",
6610 		.data		=
6611 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6612 		.maxlen		= sizeof(int),
6613 		.mode		= 0644,
6614 		.proc_handler	= proc_dointvec_ms_jiffies,
6615 	},
6616 	{
6617 		.procname	= "use_tempaddr",
6618 		.data		= &ipv6_devconf.use_tempaddr,
6619 		.maxlen		= sizeof(int),
6620 		.mode		= 0644,
6621 		.proc_handler	= proc_dointvec,
6622 	},
6623 	{
6624 		.procname	= "temp_valid_lft",
6625 		.data		= &ipv6_devconf.temp_valid_lft,
6626 		.maxlen		= sizeof(int),
6627 		.mode		= 0644,
6628 		.proc_handler	= proc_dointvec,
6629 	},
6630 	{
6631 		.procname	= "temp_prefered_lft",
6632 		.data		= &ipv6_devconf.temp_prefered_lft,
6633 		.maxlen		= sizeof(int),
6634 		.mode		= 0644,
6635 		.proc_handler	= proc_dointvec,
6636 	},
6637 	{
6638 		.procname	= "regen_max_retry",
6639 		.data		= &ipv6_devconf.regen_max_retry,
6640 		.maxlen		= sizeof(int),
6641 		.mode		= 0644,
6642 		.proc_handler	= proc_dointvec,
6643 	},
6644 	{
6645 		.procname	= "max_desync_factor",
6646 		.data		= &ipv6_devconf.max_desync_factor,
6647 		.maxlen		= sizeof(int),
6648 		.mode		= 0644,
6649 		.proc_handler	= proc_dointvec,
6650 	},
6651 	{
6652 		.procname	= "max_addresses",
6653 		.data		= &ipv6_devconf.max_addresses,
6654 		.maxlen		= sizeof(int),
6655 		.mode		= 0644,
6656 		.proc_handler	= proc_dointvec,
6657 	},
6658 	{
6659 		.procname	= "accept_ra_defrtr",
6660 		.data		= &ipv6_devconf.accept_ra_defrtr,
6661 		.maxlen		= sizeof(int),
6662 		.mode		= 0644,
6663 		.proc_handler	= proc_dointvec,
6664 	},
6665 	{
6666 		.procname	= "accept_ra_min_hop_limit",
6667 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6668 		.maxlen		= sizeof(int),
6669 		.mode		= 0644,
6670 		.proc_handler	= proc_dointvec,
6671 	},
6672 	{
6673 		.procname	= "accept_ra_pinfo",
6674 		.data		= &ipv6_devconf.accept_ra_pinfo,
6675 		.maxlen		= sizeof(int),
6676 		.mode		= 0644,
6677 		.proc_handler	= proc_dointvec,
6678 	},
6679 #ifdef CONFIG_IPV6_ROUTER_PREF
6680 	{
6681 		.procname	= "accept_ra_rtr_pref",
6682 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6683 		.maxlen		= sizeof(int),
6684 		.mode		= 0644,
6685 		.proc_handler	= proc_dointvec,
6686 	},
6687 	{
6688 		.procname	= "router_probe_interval",
6689 		.data		= &ipv6_devconf.rtr_probe_interval,
6690 		.maxlen		= sizeof(int),
6691 		.mode		= 0644,
6692 		.proc_handler	= proc_dointvec_jiffies,
6693 	},
6694 #ifdef CONFIG_IPV6_ROUTE_INFO
6695 	{
6696 		.procname	= "accept_ra_rt_info_min_plen",
6697 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6698 		.maxlen		= sizeof(int),
6699 		.mode		= 0644,
6700 		.proc_handler	= proc_dointvec,
6701 	},
6702 	{
6703 		.procname	= "accept_ra_rt_info_max_plen",
6704 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6705 		.maxlen		= sizeof(int),
6706 		.mode		= 0644,
6707 		.proc_handler	= proc_dointvec,
6708 	},
6709 #endif
6710 #endif
6711 	{
6712 		.procname	= "proxy_ndp",
6713 		.data		= &ipv6_devconf.proxy_ndp,
6714 		.maxlen		= sizeof(int),
6715 		.mode		= 0644,
6716 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6717 	},
6718 	{
6719 		.procname	= "accept_source_route",
6720 		.data		= &ipv6_devconf.accept_source_route,
6721 		.maxlen		= sizeof(int),
6722 		.mode		= 0644,
6723 		.proc_handler	= proc_dointvec,
6724 	},
6725 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6726 	{
6727 		.procname	= "optimistic_dad",
6728 		.data		= &ipv6_devconf.optimistic_dad,
6729 		.maxlen		= sizeof(int),
6730 		.mode		= 0644,
6731 		.proc_handler   = proc_dointvec,
6732 	},
6733 	{
6734 		.procname	= "use_optimistic",
6735 		.data		= &ipv6_devconf.use_optimistic,
6736 		.maxlen		= sizeof(int),
6737 		.mode		= 0644,
6738 		.proc_handler	= proc_dointvec,
6739 	},
6740 #endif
6741 #ifdef CONFIG_IPV6_MROUTE
6742 	{
6743 		.procname	= "mc_forwarding",
6744 		.data		= &ipv6_devconf.mc_forwarding,
6745 		.maxlen		= sizeof(int),
6746 		.mode		= 0444,
6747 		.proc_handler	= proc_dointvec,
6748 	},
6749 #endif
6750 	{
6751 		.procname	= "disable_ipv6",
6752 		.data		= &ipv6_devconf.disable_ipv6,
6753 		.maxlen		= sizeof(int),
6754 		.mode		= 0644,
6755 		.proc_handler	= addrconf_sysctl_disable,
6756 	},
6757 	{
6758 		.procname	= "accept_dad",
6759 		.data		= &ipv6_devconf.accept_dad,
6760 		.maxlen		= sizeof(int),
6761 		.mode		= 0644,
6762 		.proc_handler	= proc_dointvec,
6763 	},
6764 	{
6765 		.procname	= "force_tllao",
6766 		.data		= &ipv6_devconf.force_tllao,
6767 		.maxlen		= sizeof(int),
6768 		.mode		= 0644,
6769 		.proc_handler	= proc_dointvec
6770 	},
6771 	{
6772 		.procname	= "ndisc_notify",
6773 		.data		= &ipv6_devconf.ndisc_notify,
6774 		.maxlen		= sizeof(int),
6775 		.mode		= 0644,
6776 		.proc_handler	= proc_dointvec
6777 	},
6778 	{
6779 		.procname	= "suppress_frag_ndisc",
6780 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6781 		.maxlen		= sizeof(int),
6782 		.mode		= 0644,
6783 		.proc_handler	= proc_dointvec
6784 	},
6785 	{
6786 		.procname	= "accept_ra_from_local",
6787 		.data		= &ipv6_devconf.accept_ra_from_local,
6788 		.maxlen		= sizeof(int),
6789 		.mode		= 0644,
6790 		.proc_handler	= proc_dointvec,
6791 	},
6792 	{
6793 		.procname	= "accept_ra_mtu",
6794 		.data		= &ipv6_devconf.accept_ra_mtu,
6795 		.maxlen		= sizeof(int),
6796 		.mode		= 0644,
6797 		.proc_handler	= proc_dointvec,
6798 	},
6799 	{
6800 		.procname	= "stable_secret",
6801 		.data		= &ipv6_devconf.stable_secret,
6802 		.maxlen		= IPV6_MAX_STRLEN,
6803 		.mode		= 0600,
6804 		.proc_handler	= addrconf_sysctl_stable_secret,
6805 	},
6806 	{
6807 		.procname	= "use_oif_addrs_only",
6808 		.data		= &ipv6_devconf.use_oif_addrs_only,
6809 		.maxlen		= sizeof(int),
6810 		.mode		= 0644,
6811 		.proc_handler	= proc_dointvec,
6812 	},
6813 	{
6814 		.procname	= "ignore_routes_with_linkdown",
6815 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6816 		.maxlen		= sizeof(int),
6817 		.mode		= 0644,
6818 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6819 	},
6820 	{
6821 		.procname	= "drop_unicast_in_l2_multicast",
6822 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6823 		.maxlen		= sizeof(int),
6824 		.mode		= 0644,
6825 		.proc_handler	= proc_dointvec,
6826 	},
6827 	{
6828 		.procname	= "drop_unsolicited_na",
6829 		.data		= &ipv6_devconf.drop_unsolicited_na,
6830 		.maxlen		= sizeof(int),
6831 		.mode		= 0644,
6832 		.proc_handler	= proc_dointvec,
6833 	},
6834 	{
6835 		.procname	= "keep_addr_on_down",
6836 		.data		= &ipv6_devconf.keep_addr_on_down,
6837 		.maxlen		= sizeof(int),
6838 		.mode		= 0644,
6839 		.proc_handler	= proc_dointvec,
6840 
6841 	},
6842 	{
6843 		.procname	= "seg6_enabled",
6844 		.data		= &ipv6_devconf.seg6_enabled,
6845 		.maxlen		= sizeof(int),
6846 		.mode		= 0644,
6847 		.proc_handler	= proc_dointvec,
6848 	},
6849 #ifdef CONFIG_IPV6_SEG6_HMAC
6850 	{
6851 		.procname	= "seg6_require_hmac",
6852 		.data		= &ipv6_devconf.seg6_require_hmac,
6853 		.maxlen		= sizeof(int),
6854 		.mode		= 0644,
6855 		.proc_handler	= proc_dointvec,
6856 	},
6857 #endif
6858 	{
6859 		.procname       = "enhanced_dad",
6860 		.data           = &ipv6_devconf.enhanced_dad,
6861 		.maxlen         = sizeof(int),
6862 		.mode           = 0644,
6863 		.proc_handler   = proc_dointvec,
6864 	},
6865 	{
6866 		.procname		= "addr_gen_mode",
6867 		.data			= &ipv6_devconf.addr_gen_mode,
6868 		.maxlen			= sizeof(int),
6869 		.mode			= 0644,
6870 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6871 	},
6872 	{
6873 		.procname       = "disable_policy",
6874 		.data           = &ipv6_devconf.disable_policy,
6875 		.maxlen         = sizeof(int),
6876 		.mode           = 0644,
6877 		.proc_handler   = addrconf_sysctl_disable_policy,
6878 	},
6879 	{
6880 		.procname	= "ndisc_tclass",
6881 		.data		= &ipv6_devconf.ndisc_tclass,
6882 		.maxlen		= sizeof(int),
6883 		.mode		= 0644,
6884 		.proc_handler	= proc_dointvec_minmax,
6885 		.extra1		= (void *)SYSCTL_ZERO,
6886 		.extra2		= (void *)&two_five_five,
6887 	},
6888 	{
6889 		.procname	= "rpl_seg_enabled",
6890 		.data		= &ipv6_devconf.rpl_seg_enabled,
6891 		.maxlen		= sizeof(int),
6892 		.mode		= 0644,
6893 		.proc_handler	= proc_dointvec,
6894 	},
6895 	{
6896 		/* sentinel */
6897 	}
6898 };
6899 
6900 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6901 		struct inet6_dev *idev, struct ipv6_devconf *p)
6902 {
6903 	int i, ifindex;
6904 	struct ctl_table *table;
6905 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6906 
6907 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6908 	if (!table)
6909 		goto out;
6910 
6911 	for (i = 0; table[i].data; i++) {
6912 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6913 		/* If one of these is already set, then it is not safe to
6914 		 * overwrite either of them: this makes proc_dointvec_minmax
6915 		 * usable.
6916 		 */
6917 		if (!table[i].extra1 && !table[i].extra2) {
6918 			table[i].extra1 = idev; /* embedded; no ref */
6919 			table[i].extra2 = net;
6920 		}
6921 	}
6922 
6923 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6924 
6925 	p->sysctl_header = register_net_sysctl(net, path, table);
6926 	if (!p->sysctl_header)
6927 		goto free;
6928 
6929 	if (!strcmp(dev_name, "all"))
6930 		ifindex = NETCONFA_IFINDEX_ALL;
6931 	else if (!strcmp(dev_name, "default"))
6932 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6933 	else
6934 		ifindex = idev->dev->ifindex;
6935 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6936 				     ifindex, p);
6937 	return 0;
6938 
6939 free:
6940 	kfree(table);
6941 out:
6942 	return -ENOBUFS;
6943 }
6944 
6945 static void __addrconf_sysctl_unregister(struct net *net,
6946 					 struct ipv6_devconf *p, int ifindex)
6947 {
6948 	struct ctl_table *table;
6949 
6950 	if (!p->sysctl_header)
6951 		return;
6952 
6953 	table = p->sysctl_header->ctl_table_arg;
6954 	unregister_net_sysctl_table(p->sysctl_header);
6955 	p->sysctl_header = NULL;
6956 	kfree(table);
6957 
6958 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6959 }
6960 
6961 static int addrconf_sysctl_register(struct inet6_dev *idev)
6962 {
6963 	int err;
6964 
6965 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6966 		return -EINVAL;
6967 
6968 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6969 				    &ndisc_ifinfo_sysctl_change);
6970 	if (err)
6971 		return err;
6972 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6973 					 idev, &idev->cnf);
6974 	if (err)
6975 		neigh_sysctl_unregister(idev->nd_parms);
6976 
6977 	return err;
6978 }
6979 
6980 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6981 {
6982 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6983 				     idev->dev->ifindex);
6984 	neigh_sysctl_unregister(idev->nd_parms);
6985 }
6986 
6987 
6988 #endif
6989 
6990 static int __net_init addrconf_init_net(struct net *net)
6991 {
6992 	int err = -ENOMEM;
6993 	struct ipv6_devconf *all, *dflt;
6994 
6995 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6996 	if (!all)
6997 		goto err_alloc_all;
6998 
6999 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7000 	if (!dflt)
7001 		goto err_alloc_dflt;
7002 
7003 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7004 	    !net_eq(net, &init_net)) {
7005 		switch (sysctl_devconf_inherit_init_net) {
7006 		case 1:  /* copy from init_net */
7007 			memcpy(all, init_net.ipv6.devconf_all,
7008 			       sizeof(ipv6_devconf));
7009 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7010 			       sizeof(ipv6_devconf_dflt));
7011 			break;
7012 		case 3: /* copy from the current netns */
7013 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7014 			       sizeof(ipv6_devconf));
7015 			memcpy(dflt,
7016 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7017 			       sizeof(ipv6_devconf_dflt));
7018 			break;
7019 		case 0:
7020 		case 2:
7021 			/* use compiled values */
7022 			break;
7023 		}
7024 	}
7025 
7026 	/* these will be inherited by all namespaces */
7027 	dflt->autoconf = ipv6_defaults.autoconf;
7028 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7029 
7030 	dflt->stable_secret.initialized = false;
7031 	all->stable_secret.initialized = false;
7032 
7033 	net->ipv6.devconf_all = all;
7034 	net->ipv6.devconf_dflt = dflt;
7035 
7036 #ifdef CONFIG_SYSCTL
7037 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7038 	if (err < 0)
7039 		goto err_reg_all;
7040 
7041 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7042 	if (err < 0)
7043 		goto err_reg_dflt;
7044 #endif
7045 	return 0;
7046 
7047 #ifdef CONFIG_SYSCTL
7048 err_reg_dflt:
7049 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7050 err_reg_all:
7051 	kfree(dflt);
7052 #endif
7053 err_alloc_dflt:
7054 	kfree(all);
7055 err_alloc_all:
7056 	return err;
7057 }
7058 
7059 static void __net_exit addrconf_exit_net(struct net *net)
7060 {
7061 #ifdef CONFIG_SYSCTL
7062 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7063 				     NETCONFA_IFINDEX_DEFAULT);
7064 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7065 				     NETCONFA_IFINDEX_ALL);
7066 #endif
7067 	kfree(net->ipv6.devconf_dflt);
7068 	kfree(net->ipv6.devconf_all);
7069 }
7070 
7071 static struct pernet_operations addrconf_ops = {
7072 	.init = addrconf_init_net,
7073 	.exit = addrconf_exit_net,
7074 };
7075 
7076 static struct rtnl_af_ops inet6_ops __read_mostly = {
7077 	.family		  = AF_INET6,
7078 	.fill_link_af	  = inet6_fill_link_af,
7079 	.get_link_af_size = inet6_get_link_af_size,
7080 	.validate_link_af = inet6_validate_link_af,
7081 	.set_link_af	  = inet6_set_link_af,
7082 };
7083 
7084 /*
7085  *	Init / cleanup code
7086  */
7087 
7088 int __init addrconf_init(void)
7089 {
7090 	struct inet6_dev *idev;
7091 	int i, err;
7092 
7093 	err = ipv6_addr_label_init();
7094 	if (err < 0) {
7095 		pr_crit("%s: cannot initialize default policy table: %d\n",
7096 			__func__, err);
7097 		goto out;
7098 	}
7099 
7100 	err = register_pernet_subsys(&addrconf_ops);
7101 	if (err < 0)
7102 		goto out_addrlabel;
7103 
7104 	addrconf_wq = create_workqueue("ipv6_addrconf");
7105 	if (!addrconf_wq) {
7106 		err = -ENOMEM;
7107 		goto out_nowq;
7108 	}
7109 
7110 	/* The addrconf netdev notifier requires that loopback_dev
7111 	 * has it's ipv6 private information allocated and setup
7112 	 * before it can bring up and give link-local addresses
7113 	 * to other devices which are up.
7114 	 *
7115 	 * Unfortunately, loopback_dev is not necessarily the first
7116 	 * entry in the global dev_base list of net devices.  In fact,
7117 	 * it is likely to be the very last entry on that list.
7118 	 * So this causes the notifier registry below to try and
7119 	 * give link-local addresses to all devices besides loopback_dev
7120 	 * first, then loopback_dev, which cases all the non-loopback_dev
7121 	 * devices to fail to get a link-local address.
7122 	 *
7123 	 * So, as a temporary fix, allocate the ipv6 structure for
7124 	 * loopback_dev first by hand.
7125 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7126 	 * device and it being up should be removed.
7127 	 */
7128 	rtnl_lock();
7129 	idev = ipv6_add_dev(init_net.loopback_dev);
7130 	rtnl_unlock();
7131 	if (IS_ERR(idev)) {
7132 		err = PTR_ERR(idev);
7133 		goto errlo;
7134 	}
7135 
7136 	ip6_route_init_special_entries();
7137 
7138 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7139 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7140 
7141 	register_netdevice_notifier(&ipv6_dev_notf);
7142 
7143 	addrconf_verify();
7144 
7145 	rtnl_af_register(&inet6_ops);
7146 
7147 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7148 				   NULL, inet6_dump_ifinfo, 0);
7149 	if (err < 0)
7150 		goto errout;
7151 
7152 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7153 				   inet6_rtm_newaddr, NULL, 0);
7154 	if (err < 0)
7155 		goto errout;
7156 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7157 				   inet6_rtm_deladdr, NULL, 0);
7158 	if (err < 0)
7159 		goto errout;
7160 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7161 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7162 				   RTNL_FLAG_DOIT_UNLOCKED);
7163 	if (err < 0)
7164 		goto errout;
7165 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7166 				   NULL, inet6_dump_ifmcaddr, 0);
7167 	if (err < 0)
7168 		goto errout;
7169 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7170 				   NULL, inet6_dump_ifacaddr, 0);
7171 	if (err < 0)
7172 		goto errout;
7173 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7174 				   inet6_netconf_get_devconf,
7175 				   inet6_netconf_dump_devconf,
7176 				   RTNL_FLAG_DOIT_UNLOCKED);
7177 	if (err < 0)
7178 		goto errout;
7179 	err = ipv6_addr_label_rtnl_register();
7180 	if (err < 0)
7181 		goto errout;
7182 
7183 	return 0;
7184 errout:
7185 	rtnl_unregister_all(PF_INET6);
7186 	rtnl_af_unregister(&inet6_ops);
7187 	unregister_netdevice_notifier(&ipv6_dev_notf);
7188 errlo:
7189 	destroy_workqueue(addrconf_wq);
7190 out_nowq:
7191 	unregister_pernet_subsys(&addrconf_ops);
7192 out_addrlabel:
7193 	ipv6_addr_label_cleanup();
7194 out:
7195 	return err;
7196 }
7197 
7198 void addrconf_cleanup(void)
7199 {
7200 	struct net_device *dev;
7201 	int i;
7202 
7203 	unregister_netdevice_notifier(&ipv6_dev_notf);
7204 	unregister_pernet_subsys(&addrconf_ops);
7205 	ipv6_addr_label_cleanup();
7206 
7207 	rtnl_af_unregister(&inet6_ops);
7208 
7209 	rtnl_lock();
7210 
7211 	/* clean dev list */
7212 	for_each_netdev(&init_net, dev) {
7213 		if (__in6_dev_get(dev) == NULL)
7214 			continue;
7215 		addrconf_ifdown(dev, true);
7216 	}
7217 	addrconf_ifdown(init_net.loopback_dev, true);
7218 
7219 	/*
7220 	 *	Check hash table.
7221 	 */
7222 	spin_lock_bh(&addrconf_hash_lock);
7223 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7224 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7225 	spin_unlock_bh(&addrconf_hash_lock);
7226 	cancel_delayed_work(&addr_chk_work);
7227 	rtnl_unlock();
7228 
7229 	destroy_workqueue(addrconf_wq);
7230 }
7231