xref: /linux/net/ipv6/addrconf.c (revision b4748e7ab731e436cf5db4786358ada5dd2db6dd)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181 				   bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188 				struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191 	.forwarding		= 0,
192 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
193 	.mtu6			= IPV6_MIN_MTU,
194 	.accept_ra		= 1,
195 	.accept_redirects	= 1,
196 	.autoconf		= 1,
197 	.force_mld_version	= 0,
198 	.mldv1_unsolicited_report_interval = 10 * HZ,
199 	.mldv2_unsolicited_report_interval = HZ,
200 	.dad_transmits		= 1,
201 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
202 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
203 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
205 	.use_tempaddr		= 0,
206 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
207 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
208 	.regen_max_retry	= REGEN_MAX_RETRY,
209 	.max_desync_factor	= MAX_DESYNC_FACTOR,
210 	.max_addresses		= IPV6_MAX_ADDRESSES,
211 	.accept_ra_defrtr	= 1,
212 	.accept_ra_from_local	= 0,
213 	.accept_ra_min_hop_limit= 1,
214 	.accept_ra_pinfo	= 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216 	.accept_ra_rtr_pref	= 1,
217 	.rtr_probe_interval	= 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219 	.accept_ra_rt_info_min_plen = 0,
220 	.accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223 	.proxy_ndp		= 0,
224 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
225 	.disable_ipv6		= 0,
226 	.accept_dad		= 0,
227 	.suppress_frag_ndisc	= 1,
228 	.accept_ra_mtu		= 1,
229 	.stable_secret		= {
230 		.initialized = false,
231 	},
232 	.use_oif_addrs_only	= 0,
233 	.ignore_routes_with_linkdown = 0,
234 	.keep_addr_on_down	= 0,
235 	.seg6_enabled		= 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237 	.seg6_require_hmac	= 0,
238 #endif
239 	.enhanced_dad           = 1,
240 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
241 	.disable_policy		= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.accept_ra_from_local	= 0,
267 	.accept_ra_min_hop_limit= 1,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 
389 	ndev->cnf.mtu6 = dev->mtu;
390 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
391 	if (!ndev->nd_parms) {
392 		kfree(ndev);
393 		return ERR_PTR(err);
394 	}
395 	if (ndev->cnf.forwarding)
396 		dev_disable_lro(dev);
397 	/* We refer to the device */
398 	dev_hold(dev);
399 
400 	if (snmp6_alloc_dev(ndev) < 0) {
401 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
402 			   __func__);
403 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
404 		dev_put(dev);
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 
409 	if (snmp6_register_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
411 			   __func__, dev->name);
412 		goto err_release;
413 	}
414 
415 	/* One reference from device. */
416 	refcount_set(&ndev->refcnt, 1);
417 
418 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
419 		ndev->cnf.accept_dad = -1;
420 
421 #if IS_ENABLED(CONFIG_IPV6_SIT)
422 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
423 		pr_info("%s: Disabled Multicast RS\n", dev->name);
424 		ndev->cnf.rtr_solicits = 0;
425 	}
426 #endif
427 
428 	INIT_LIST_HEAD(&ndev->tempaddr_list);
429 	ndev->desync_factor = U32_MAX;
430 	if ((dev->flags&IFF_LOOPBACK) ||
431 	    dev->type == ARPHRD_TUNNEL ||
432 	    dev->type == ARPHRD_TUNNEL6 ||
433 	    dev->type == ARPHRD_SIT ||
434 	    dev->type == ARPHRD_NONE) {
435 		ndev->cnf.use_tempaddr = -1;
436 	} else
437 		ipv6_regen_rndid(ndev);
438 
439 	ndev->token = in6addr_any;
440 
441 	if (netif_running(dev) && addrconf_link_ready(dev))
442 		ndev->if_flags |= IF_READY;
443 
444 	ipv6_mc_init_dev(ndev);
445 	ndev->tstamp = jiffies;
446 	err = addrconf_sysctl_register(ndev);
447 	if (err) {
448 		ipv6_mc_destroy_dev(ndev);
449 		snmp6_unregister_dev(ndev);
450 		goto err_release;
451 	}
452 	/* protected by rtnl_lock */
453 	rcu_assign_pointer(dev->ip6_ptr, ndev);
454 
455 	/* Join interface-local all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
457 
458 	/* Join all-node multicast group */
459 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
460 
461 	/* Join all-router multicast group if forwarding is set */
462 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
463 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
464 
465 	return ndev;
466 
467 err_release:
468 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
469 	ndev->dead = 1;
470 	in6_dev_finish_destroy(ndev);
471 	return ERR_PTR(err);
472 }
473 
474 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
475 {
476 	struct inet6_dev *idev;
477 
478 	ASSERT_RTNL();
479 
480 	idev = __in6_dev_get(dev);
481 	if (!idev) {
482 		idev = ipv6_add_dev(dev);
483 		if (IS_ERR(idev))
484 			return NULL;
485 	}
486 
487 	if (dev->flags&IFF_UP)
488 		ipv6_mc_up(idev);
489 	return idev;
490 }
491 
492 static int inet6_netconf_msgsize_devconf(int type)
493 {
494 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
495 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
496 	bool all = false;
497 
498 	if (type == NETCONFA_ALL)
499 		all = true;
500 
501 	if (all || type == NETCONFA_FORWARDING)
502 		size += nla_total_size(4);
503 #ifdef CONFIG_IPV6_MROUTE
504 	if (all || type == NETCONFA_MC_FORWARDING)
505 		size += nla_total_size(4);
506 #endif
507 	if (all || type == NETCONFA_PROXY_NEIGH)
508 		size += nla_total_size(4);
509 
510 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
511 		size += nla_total_size(4);
512 
513 	return size;
514 }
515 
516 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
517 				      struct ipv6_devconf *devconf, u32 portid,
518 				      u32 seq, int event, unsigned int flags,
519 				      int type)
520 {
521 	struct nlmsghdr  *nlh;
522 	struct netconfmsg *ncm;
523 	bool all = false;
524 
525 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
526 			flags);
527 	if (!nlh)
528 		return -EMSGSIZE;
529 
530 	if (type == NETCONFA_ALL)
531 		all = true;
532 
533 	ncm = nlmsg_data(nlh);
534 	ncm->ncm_family = AF_INET6;
535 
536 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
537 		goto nla_put_failure;
538 
539 	if (!devconf)
540 		goto out;
541 
542 	if ((all || type == NETCONFA_FORWARDING) &&
543 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
544 		goto nla_put_failure;
545 #ifdef CONFIG_IPV6_MROUTE
546 	if ((all || type == NETCONFA_MC_FORWARDING) &&
547 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
548 			devconf->mc_forwarding) < 0)
549 		goto nla_put_failure;
550 #endif
551 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
552 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
553 		goto nla_put_failure;
554 
555 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
556 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
557 			devconf->ignore_routes_with_linkdown) < 0)
558 		goto nla_put_failure;
559 
560 out:
561 	nlmsg_end(skb, nlh);
562 	return 0;
563 
564 nla_put_failure:
565 	nlmsg_cancel(skb, nlh);
566 	return -EMSGSIZE;
567 }
568 
569 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
570 				  int ifindex, struct ipv6_devconf *devconf)
571 {
572 	struct sk_buff *skb;
573 	int err = -ENOBUFS;
574 
575 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
576 	if (!skb)
577 		goto errout;
578 
579 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
580 					 event, 0, type);
581 	if (err < 0) {
582 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
583 		WARN_ON(err == -EMSGSIZE);
584 		kfree_skb(skb);
585 		goto errout;
586 	}
587 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
588 	return;
589 errout:
590 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
591 }
592 
593 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
594 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
595 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
596 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
597 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
598 };
599 
600 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
601 				     struct nlmsghdr *nlh,
602 				     struct netlink_ext_ack *extack)
603 {
604 	struct net *net = sock_net(in_skb->sk);
605 	struct nlattr *tb[NETCONFA_MAX+1];
606 	struct inet6_dev *in6_dev = NULL;
607 	struct net_device *dev = NULL;
608 	struct netconfmsg *ncm;
609 	struct sk_buff *skb;
610 	struct ipv6_devconf *devconf;
611 	int ifindex;
612 	int err;
613 
614 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
615 			  devconf_ipv6_policy, extack);
616 	if (err < 0)
617 		return err;
618 
619 	if (!tb[NETCONFA_IFINDEX])
620 		return -EINVAL;
621 
622 	err = -EINVAL;
623 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
624 	switch (ifindex) {
625 	case NETCONFA_IFINDEX_ALL:
626 		devconf = net->ipv6.devconf_all;
627 		break;
628 	case NETCONFA_IFINDEX_DEFAULT:
629 		devconf = net->ipv6.devconf_dflt;
630 		break;
631 	default:
632 		dev = dev_get_by_index(net, ifindex);
633 		if (!dev)
634 			return -EINVAL;
635 		in6_dev = in6_dev_get(dev);
636 		if (!in6_dev)
637 			goto errout;
638 		devconf = &in6_dev->cnf;
639 		break;
640 	}
641 
642 	err = -ENOBUFS;
643 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
644 	if (!skb)
645 		goto errout;
646 
647 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
648 					 NETLINK_CB(in_skb).portid,
649 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
650 					 NETCONFA_ALL);
651 	if (err < 0) {
652 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
653 		WARN_ON(err == -EMSGSIZE);
654 		kfree_skb(skb);
655 		goto errout;
656 	}
657 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
658 errout:
659 	if (in6_dev)
660 		in6_dev_put(in6_dev);
661 	if (dev)
662 		dev_put(dev);
663 	return err;
664 }
665 
666 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
667 				      struct netlink_callback *cb)
668 {
669 	const struct nlmsghdr *nlh = cb->nlh;
670 	struct net *net = sock_net(skb->sk);
671 	int h, s_h;
672 	int idx, s_idx;
673 	struct net_device *dev;
674 	struct inet6_dev *idev;
675 	struct hlist_head *head;
676 
677 	if (cb->strict_check) {
678 		struct netlink_ext_ack *extack = cb->extack;
679 		struct netconfmsg *ncm;
680 
681 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
682 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
683 			return -EINVAL;
684 		}
685 
686 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
687 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
688 			return -EINVAL;
689 		}
690 	}
691 
692 	s_h = cb->args[0];
693 	s_idx = idx = cb->args[1];
694 
695 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
696 		idx = 0;
697 		head = &net->dev_index_head[h];
698 		rcu_read_lock();
699 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
700 			  net->dev_base_seq;
701 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
702 			if (idx < s_idx)
703 				goto cont;
704 			idev = __in6_dev_get(dev);
705 			if (!idev)
706 				goto cont;
707 
708 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
709 						       &idev->cnf,
710 						       NETLINK_CB(cb->skb).portid,
711 						       nlh->nlmsg_seq,
712 						       RTM_NEWNETCONF,
713 						       NLM_F_MULTI,
714 						       NETCONFA_ALL) < 0) {
715 				rcu_read_unlock();
716 				goto done;
717 			}
718 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
719 cont:
720 			idx++;
721 		}
722 		rcu_read_unlock();
723 	}
724 	if (h == NETDEV_HASHENTRIES) {
725 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
726 					       net->ipv6.devconf_all,
727 					       NETLINK_CB(cb->skb).portid,
728 					       nlh->nlmsg_seq,
729 					       RTM_NEWNETCONF, NLM_F_MULTI,
730 					       NETCONFA_ALL) < 0)
731 			goto done;
732 		else
733 			h++;
734 	}
735 	if (h == NETDEV_HASHENTRIES + 1) {
736 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
737 					       net->ipv6.devconf_dflt,
738 					       NETLINK_CB(cb->skb).portid,
739 					       nlh->nlmsg_seq,
740 					       RTM_NEWNETCONF, NLM_F_MULTI,
741 					       NETCONFA_ALL) < 0)
742 			goto done;
743 		else
744 			h++;
745 	}
746 done:
747 	cb->args[0] = h;
748 	cb->args[1] = idx;
749 
750 	return skb->len;
751 }
752 
753 #ifdef CONFIG_SYSCTL
754 static void dev_forward_change(struct inet6_dev *idev)
755 {
756 	struct net_device *dev;
757 	struct inet6_ifaddr *ifa;
758 
759 	if (!idev)
760 		return;
761 	dev = idev->dev;
762 	if (idev->cnf.forwarding)
763 		dev_disable_lro(dev);
764 	if (dev->flags & IFF_MULTICAST) {
765 		if (idev->cnf.forwarding) {
766 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
767 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
768 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
769 		} else {
770 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
771 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
772 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
773 		}
774 	}
775 
776 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
777 		if (ifa->flags&IFA_F_TENTATIVE)
778 			continue;
779 		if (idev->cnf.forwarding)
780 			addrconf_join_anycast(ifa);
781 		else
782 			addrconf_leave_anycast(ifa);
783 	}
784 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
785 				     NETCONFA_FORWARDING,
786 				     dev->ifindex, &idev->cnf);
787 }
788 
789 
790 static void addrconf_forward_change(struct net *net, __s32 newf)
791 {
792 	struct net_device *dev;
793 	struct inet6_dev *idev;
794 
795 	for_each_netdev(net, dev) {
796 		idev = __in6_dev_get(dev);
797 		if (idev) {
798 			int changed = (!idev->cnf.forwarding) ^ (!newf);
799 			idev->cnf.forwarding = newf;
800 			if (changed)
801 				dev_forward_change(idev);
802 		}
803 	}
804 }
805 
806 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
807 {
808 	struct net *net;
809 	int old;
810 
811 	if (!rtnl_trylock())
812 		return restart_syscall();
813 
814 	net = (struct net *)table->extra2;
815 	old = *p;
816 	*p = newf;
817 
818 	if (p == &net->ipv6.devconf_dflt->forwarding) {
819 		if ((!newf) ^ (!old))
820 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
821 						     NETCONFA_FORWARDING,
822 						     NETCONFA_IFINDEX_DEFAULT,
823 						     net->ipv6.devconf_dflt);
824 		rtnl_unlock();
825 		return 0;
826 	}
827 
828 	if (p == &net->ipv6.devconf_all->forwarding) {
829 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
830 
831 		net->ipv6.devconf_dflt->forwarding = newf;
832 		if ((!newf) ^ (!old_dflt))
833 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
834 						     NETCONFA_FORWARDING,
835 						     NETCONFA_IFINDEX_DEFAULT,
836 						     net->ipv6.devconf_dflt);
837 
838 		addrconf_forward_change(net, newf);
839 		if ((!newf) ^ (!old))
840 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
841 						     NETCONFA_FORWARDING,
842 						     NETCONFA_IFINDEX_ALL,
843 						     net->ipv6.devconf_all);
844 	} else if ((!newf) ^ (!old))
845 		dev_forward_change((struct inet6_dev *)table->extra1);
846 	rtnl_unlock();
847 
848 	if (newf)
849 		rt6_purge_dflt_routers(net);
850 	return 1;
851 }
852 
853 static void addrconf_linkdown_change(struct net *net, __s32 newf)
854 {
855 	struct net_device *dev;
856 	struct inet6_dev *idev;
857 
858 	for_each_netdev(net, dev) {
859 		idev = __in6_dev_get(dev);
860 		if (idev) {
861 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
862 
863 			idev->cnf.ignore_routes_with_linkdown = newf;
864 			if (changed)
865 				inet6_netconf_notify_devconf(dev_net(dev),
866 							     RTM_NEWNETCONF,
867 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
868 							     dev->ifindex,
869 							     &idev->cnf);
870 		}
871 	}
872 }
873 
874 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
875 {
876 	struct net *net;
877 	int old;
878 
879 	if (!rtnl_trylock())
880 		return restart_syscall();
881 
882 	net = (struct net *)table->extra2;
883 	old = *p;
884 	*p = newf;
885 
886 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
887 		if ((!newf) ^ (!old))
888 			inet6_netconf_notify_devconf(net,
889 						     RTM_NEWNETCONF,
890 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
891 						     NETCONFA_IFINDEX_DEFAULT,
892 						     net->ipv6.devconf_dflt);
893 		rtnl_unlock();
894 		return 0;
895 	}
896 
897 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
898 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
899 		addrconf_linkdown_change(net, newf);
900 		if ((!newf) ^ (!old))
901 			inet6_netconf_notify_devconf(net,
902 						     RTM_NEWNETCONF,
903 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
904 						     NETCONFA_IFINDEX_ALL,
905 						     net->ipv6.devconf_all);
906 	}
907 	rtnl_unlock();
908 
909 	return 1;
910 }
911 
912 #endif
913 
914 /* Nobody refers to this ifaddr, destroy it */
915 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
916 {
917 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
918 
919 #ifdef NET_REFCNT_DEBUG
920 	pr_debug("%s\n", __func__);
921 #endif
922 
923 	in6_dev_put(ifp->idev);
924 
925 	if (cancel_delayed_work(&ifp->dad_work))
926 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
927 			  ifp);
928 
929 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
930 		pr_warn("Freeing alive inet6 address %p\n", ifp);
931 		return;
932 	}
933 
934 	kfree_rcu(ifp, rcu);
935 }
936 
937 static void
938 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
939 {
940 	struct list_head *p;
941 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
942 
943 	/*
944 	 * Each device address list is sorted in order of scope -
945 	 * global before linklocal.
946 	 */
947 	list_for_each(p, &idev->addr_list) {
948 		struct inet6_ifaddr *ifa
949 			= list_entry(p, struct inet6_ifaddr, if_list);
950 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
951 			break;
952 	}
953 
954 	list_add_tail_rcu(&ifp->if_list, p);
955 }
956 
957 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
958 {
959 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
960 
961 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
962 }
963 
964 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
965 			       struct net_device *dev, unsigned int hash)
966 {
967 	struct inet6_ifaddr *ifp;
968 
969 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
970 		if (!net_eq(dev_net(ifp->idev->dev), net))
971 			continue;
972 		if (ipv6_addr_equal(&ifp->addr, addr)) {
973 			if (!dev || ifp->idev->dev == dev)
974 				return true;
975 		}
976 	}
977 	return false;
978 }
979 
980 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
981 {
982 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
983 	int err = 0;
984 
985 	spin_lock(&addrconf_hash_lock);
986 
987 	/* Ignore adding duplicate addresses on an interface */
988 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
989 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
990 		err = -EEXIST;
991 	} else {
992 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
993 	}
994 
995 	spin_unlock(&addrconf_hash_lock);
996 
997 	return err;
998 }
999 
1000 /* On success it returns ifp with increased reference count */
1001 
1002 static struct inet6_ifaddr *
1003 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1004 	      bool can_block, struct netlink_ext_ack *extack)
1005 {
1006 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1007 	int addr_type = ipv6_addr_type(cfg->pfx);
1008 	struct net *net = dev_net(idev->dev);
1009 	struct inet6_ifaddr *ifa = NULL;
1010 	struct fib6_info *f6i = NULL;
1011 	int err = 0;
1012 
1013 	if (addr_type == IPV6_ADDR_ANY ||
1014 	    addr_type & IPV6_ADDR_MULTICAST ||
1015 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1016 	     !netif_is_l3_master(idev->dev) &&
1017 	     addr_type & IPV6_ADDR_LOOPBACK))
1018 		return ERR_PTR(-EADDRNOTAVAIL);
1019 
1020 	if (idev->dead) {
1021 		err = -ENODEV;			/*XXX*/
1022 		goto out;
1023 	}
1024 
1025 	if (idev->cnf.disable_ipv6) {
1026 		err = -EACCES;
1027 		goto out;
1028 	}
1029 
1030 	/* validator notifier needs to be blocking;
1031 	 * do not call in atomic context
1032 	 */
1033 	if (can_block) {
1034 		struct in6_validator_info i6vi = {
1035 			.i6vi_addr = *cfg->pfx,
1036 			.i6vi_dev = idev,
1037 			.extack = extack,
1038 		};
1039 
1040 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1041 		err = notifier_to_errno(err);
1042 		if (err < 0)
1043 			goto out;
1044 	}
1045 
1046 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1047 	if (!ifa) {
1048 		err = -ENOBUFS;
1049 		goto out;
1050 	}
1051 
1052 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1053 	if (IS_ERR(f6i)) {
1054 		err = PTR_ERR(f6i);
1055 		f6i = NULL;
1056 		goto out;
1057 	}
1058 
1059 	if (net->ipv6.devconf_all->disable_policy ||
1060 	    idev->cnf.disable_policy)
1061 		f6i->dst_nopolicy = true;
1062 
1063 	neigh_parms_data_state_setall(idev->nd_parms);
1064 
1065 	ifa->addr = *cfg->pfx;
1066 	if (cfg->peer_pfx)
1067 		ifa->peer_addr = *cfg->peer_pfx;
1068 
1069 	spin_lock_init(&ifa->lock);
1070 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1071 	INIT_HLIST_NODE(&ifa->addr_lst);
1072 	ifa->scope = cfg->scope;
1073 	ifa->prefix_len = cfg->plen;
1074 	ifa->rt_priority = cfg->rt_priority;
1075 	ifa->flags = cfg->ifa_flags;
1076 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1077 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1078 		ifa->flags |= IFA_F_TENTATIVE;
1079 	ifa->valid_lft = cfg->valid_lft;
1080 	ifa->prefered_lft = cfg->preferred_lft;
1081 	ifa->cstamp = ifa->tstamp = jiffies;
1082 	ifa->tokenized = false;
1083 
1084 	ifa->rt = f6i;
1085 
1086 	ifa->idev = idev;
1087 	in6_dev_hold(idev);
1088 
1089 	/* For caller */
1090 	refcount_set(&ifa->refcnt, 1);
1091 
1092 	rcu_read_lock_bh();
1093 
1094 	err = ipv6_add_addr_hash(idev->dev, ifa);
1095 	if (err < 0) {
1096 		rcu_read_unlock_bh();
1097 		goto out;
1098 	}
1099 
1100 	write_lock(&idev->lock);
1101 
1102 	/* Add to inet6_dev unicast addr list. */
1103 	ipv6_link_dev_addr(idev, ifa);
1104 
1105 	if (ifa->flags&IFA_F_TEMPORARY) {
1106 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1107 		in6_ifa_hold(ifa);
1108 	}
1109 
1110 	in6_ifa_hold(ifa);
1111 	write_unlock(&idev->lock);
1112 
1113 	rcu_read_unlock_bh();
1114 
1115 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1116 out:
1117 	if (unlikely(err < 0)) {
1118 		fib6_info_release(f6i);
1119 
1120 		if (ifa) {
1121 			if (ifa->idev)
1122 				in6_dev_put(ifa->idev);
1123 			kfree(ifa);
1124 		}
1125 		ifa = ERR_PTR(err);
1126 	}
1127 
1128 	return ifa;
1129 }
1130 
1131 enum cleanup_prefix_rt_t {
1132 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1133 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1134 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1135 };
1136 
1137 /*
1138  * Check, whether the prefix for ifp would still need a prefix route
1139  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1140  * constants.
1141  *
1142  * 1) we don't purge prefix if address was not permanent.
1143  *    prefix is managed by its own lifetime.
1144  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1145  * 3) if there are no addresses, delete prefix.
1146  * 4) if there are still other permanent address(es),
1147  *    corresponding prefix is still permanent.
1148  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1149  *    don't purge the prefix, assume user space is managing it.
1150  * 6) otherwise, update prefix lifetime to the
1151  *    longest valid lifetime among the corresponding
1152  *    addresses on the device.
1153  *    Note: subsequent RA will update lifetime.
1154  **/
1155 static enum cleanup_prefix_rt_t
1156 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1157 {
1158 	struct inet6_ifaddr *ifa;
1159 	struct inet6_dev *idev = ifp->idev;
1160 	unsigned long lifetime;
1161 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1162 
1163 	*expires = jiffies;
1164 
1165 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1166 		if (ifa == ifp)
1167 			continue;
1168 		if (ifa->prefix_len != ifp->prefix_len ||
1169 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1170 				       ifp->prefix_len))
1171 			continue;
1172 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1173 			return CLEANUP_PREFIX_RT_NOP;
1174 
1175 		action = CLEANUP_PREFIX_RT_EXPIRE;
1176 
1177 		spin_lock(&ifa->lock);
1178 
1179 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1180 		/*
1181 		 * Note: Because this address is
1182 		 * not permanent, lifetime <
1183 		 * LONG_MAX / HZ here.
1184 		 */
1185 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1186 			*expires = ifa->tstamp + lifetime * HZ;
1187 		spin_unlock(&ifa->lock);
1188 	}
1189 
1190 	return action;
1191 }
1192 
1193 static void
1194 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1195 {
1196 	struct fib6_info *f6i;
1197 
1198 	f6i = addrconf_get_prefix_route(&ifp->addr,
1199 				       ifp->prefix_len,
1200 				       ifp->idev->dev,
1201 				       0, RTF_GATEWAY | RTF_DEFAULT);
1202 	if (f6i) {
1203 		if (del_rt)
1204 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1205 		else {
1206 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1207 				fib6_set_expires(f6i, expires);
1208 			fib6_info_release(f6i);
1209 		}
1210 	}
1211 }
1212 
1213 
1214 /* This function wants to get referenced ifp and releases it before return */
1215 
1216 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1217 {
1218 	int state;
1219 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1220 	unsigned long expires;
1221 
1222 	ASSERT_RTNL();
1223 
1224 	spin_lock_bh(&ifp->lock);
1225 	state = ifp->state;
1226 	ifp->state = INET6_IFADDR_STATE_DEAD;
1227 	spin_unlock_bh(&ifp->lock);
1228 
1229 	if (state == INET6_IFADDR_STATE_DEAD)
1230 		goto out;
1231 
1232 	spin_lock_bh(&addrconf_hash_lock);
1233 	hlist_del_init_rcu(&ifp->addr_lst);
1234 	spin_unlock_bh(&addrconf_hash_lock);
1235 
1236 	write_lock_bh(&ifp->idev->lock);
1237 
1238 	if (ifp->flags&IFA_F_TEMPORARY) {
1239 		list_del(&ifp->tmp_list);
1240 		if (ifp->ifpub) {
1241 			in6_ifa_put(ifp->ifpub);
1242 			ifp->ifpub = NULL;
1243 		}
1244 		__in6_ifa_put(ifp);
1245 	}
1246 
1247 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1248 		action = check_cleanup_prefix_route(ifp, &expires);
1249 
1250 	list_del_rcu(&ifp->if_list);
1251 	__in6_ifa_put(ifp);
1252 
1253 	write_unlock_bh(&ifp->idev->lock);
1254 
1255 	addrconf_del_dad_work(ifp);
1256 
1257 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1258 
1259 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1260 
1261 	if (action != CLEANUP_PREFIX_RT_NOP) {
1262 		cleanup_prefix_route(ifp, expires,
1263 			action == CLEANUP_PREFIX_RT_DEL);
1264 	}
1265 
1266 	/* clean up prefsrc entries */
1267 	rt6_remove_prefsrc(ifp);
1268 out:
1269 	in6_ifa_put(ifp);
1270 }
1271 
1272 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1273 				struct inet6_ifaddr *ift,
1274 				bool block)
1275 {
1276 	struct inet6_dev *idev = ifp->idev;
1277 	struct in6_addr addr, *tmpaddr;
1278 	unsigned long tmp_tstamp, age;
1279 	unsigned long regen_advance;
1280 	struct ifa6_config cfg;
1281 	int ret = 0;
1282 	unsigned long now = jiffies;
1283 	long max_desync_factor;
1284 	s32 cnf_temp_preferred_lft;
1285 
1286 	write_lock_bh(&idev->lock);
1287 	if (ift) {
1288 		spin_lock_bh(&ift->lock);
1289 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1290 		spin_unlock_bh(&ift->lock);
1291 		tmpaddr = &addr;
1292 	} else {
1293 		tmpaddr = NULL;
1294 	}
1295 retry:
1296 	in6_dev_hold(idev);
1297 	if (idev->cnf.use_tempaddr <= 0) {
1298 		write_unlock_bh(&idev->lock);
1299 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1300 		in6_dev_put(idev);
1301 		ret = -1;
1302 		goto out;
1303 	}
1304 	spin_lock_bh(&ifp->lock);
1305 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1306 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1307 		spin_unlock_bh(&ifp->lock);
1308 		write_unlock_bh(&idev->lock);
1309 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1310 			__func__);
1311 		in6_dev_put(idev);
1312 		ret = -1;
1313 		goto out;
1314 	}
1315 	in6_ifa_hold(ifp);
1316 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1317 	ipv6_try_regen_rndid(idev, tmpaddr);
1318 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1319 	age = (now - ifp->tstamp) / HZ;
1320 
1321 	regen_advance = idev->cnf.regen_max_retry *
1322 			idev->cnf.dad_transmits *
1323 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1324 
1325 	/* recalculate max_desync_factor each time and update
1326 	 * idev->desync_factor if it's larger
1327 	 */
1328 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1329 	max_desync_factor = min_t(__u32,
1330 				  idev->cnf.max_desync_factor,
1331 				  cnf_temp_preferred_lft - regen_advance);
1332 
1333 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1334 		if (max_desync_factor > 0) {
1335 			get_random_bytes(&idev->desync_factor,
1336 					 sizeof(idev->desync_factor));
1337 			idev->desync_factor %= max_desync_factor;
1338 		} else {
1339 			idev->desync_factor = 0;
1340 		}
1341 	}
1342 
1343 	memset(&cfg, 0, sizeof(cfg));
1344 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1345 			      idev->cnf.temp_valid_lft + age);
1346 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1347 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1348 
1349 	cfg.plen = ifp->prefix_len;
1350 	tmp_tstamp = ifp->tstamp;
1351 	spin_unlock_bh(&ifp->lock);
1352 
1353 	write_unlock_bh(&idev->lock);
1354 
1355 	/* A temporary address is created only if this calculated Preferred
1356 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1357 	 * an implementation must not create a temporary address with a zero
1358 	 * Preferred Lifetime.
1359 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1360 	 * temporary addresses being generated.
1361 	 */
1362 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1363 	if (cfg.preferred_lft <= regen_advance + age) {
1364 		in6_ifa_put(ifp);
1365 		in6_dev_put(idev);
1366 		ret = -1;
1367 		goto out;
1368 	}
1369 
1370 	cfg.ifa_flags = IFA_F_TEMPORARY;
1371 	/* set in addrconf_prefix_rcv() */
1372 	if (ifp->flags & IFA_F_OPTIMISTIC)
1373 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1374 
1375 	cfg.pfx = &addr;
1376 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1377 
1378 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1379 	if (IS_ERR(ift)) {
1380 		in6_ifa_put(ifp);
1381 		in6_dev_put(idev);
1382 		pr_info("%s: retry temporary address regeneration\n", __func__);
1383 		tmpaddr = &addr;
1384 		write_lock_bh(&idev->lock);
1385 		goto retry;
1386 	}
1387 
1388 	spin_lock_bh(&ift->lock);
1389 	ift->ifpub = ifp;
1390 	ift->cstamp = now;
1391 	ift->tstamp = tmp_tstamp;
1392 	spin_unlock_bh(&ift->lock);
1393 
1394 	addrconf_dad_start(ift);
1395 	in6_ifa_put(ift);
1396 	in6_dev_put(idev);
1397 out:
1398 	return ret;
1399 }
1400 
1401 /*
1402  *	Choose an appropriate source address (RFC3484)
1403  */
1404 enum {
1405 	IPV6_SADDR_RULE_INIT = 0,
1406 	IPV6_SADDR_RULE_LOCAL,
1407 	IPV6_SADDR_RULE_SCOPE,
1408 	IPV6_SADDR_RULE_PREFERRED,
1409 #ifdef CONFIG_IPV6_MIP6
1410 	IPV6_SADDR_RULE_HOA,
1411 #endif
1412 	IPV6_SADDR_RULE_OIF,
1413 	IPV6_SADDR_RULE_LABEL,
1414 	IPV6_SADDR_RULE_PRIVACY,
1415 	IPV6_SADDR_RULE_ORCHID,
1416 	IPV6_SADDR_RULE_PREFIX,
1417 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1418 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1419 #endif
1420 	IPV6_SADDR_RULE_MAX
1421 };
1422 
1423 struct ipv6_saddr_score {
1424 	int			rule;
1425 	int			addr_type;
1426 	struct inet6_ifaddr	*ifa;
1427 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1428 	int			scopedist;
1429 	int			matchlen;
1430 };
1431 
1432 struct ipv6_saddr_dst {
1433 	const struct in6_addr *addr;
1434 	int ifindex;
1435 	int scope;
1436 	int label;
1437 	unsigned int prefs;
1438 };
1439 
1440 static inline int ipv6_saddr_preferred(int type)
1441 {
1442 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1443 		return 1;
1444 	return 0;
1445 }
1446 
1447 static bool ipv6_use_optimistic_addr(struct net *net,
1448 				     struct inet6_dev *idev)
1449 {
1450 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1451 	if (!idev)
1452 		return false;
1453 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1454 		return false;
1455 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1456 		return false;
1457 
1458 	return true;
1459 #else
1460 	return false;
1461 #endif
1462 }
1463 
1464 static bool ipv6_allow_optimistic_dad(struct net *net,
1465 				      struct inet6_dev *idev)
1466 {
1467 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1468 	if (!idev)
1469 		return false;
1470 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1471 		return false;
1472 
1473 	return true;
1474 #else
1475 	return false;
1476 #endif
1477 }
1478 
1479 static int ipv6_get_saddr_eval(struct net *net,
1480 			       struct ipv6_saddr_score *score,
1481 			       struct ipv6_saddr_dst *dst,
1482 			       int i)
1483 {
1484 	int ret;
1485 
1486 	if (i <= score->rule) {
1487 		switch (i) {
1488 		case IPV6_SADDR_RULE_SCOPE:
1489 			ret = score->scopedist;
1490 			break;
1491 		case IPV6_SADDR_RULE_PREFIX:
1492 			ret = score->matchlen;
1493 			break;
1494 		default:
1495 			ret = !!test_bit(i, score->scorebits);
1496 		}
1497 		goto out;
1498 	}
1499 
1500 	switch (i) {
1501 	case IPV6_SADDR_RULE_INIT:
1502 		/* Rule 0: remember if hiscore is not ready yet */
1503 		ret = !!score->ifa;
1504 		break;
1505 	case IPV6_SADDR_RULE_LOCAL:
1506 		/* Rule 1: Prefer same address */
1507 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1508 		break;
1509 	case IPV6_SADDR_RULE_SCOPE:
1510 		/* Rule 2: Prefer appropriate scope
1511 		 *
1512 		 *      ret
1513 		 *       ^
1514 		 *    -1 |  d 15
1515 		 *    ---+--+-+---> scope
1516 		 *       |
1517 		 *       |             d is scope of the destination.
1518 		 *  B-d  |  \
1519 		 *       |   \      <- smaller scope is better if
1520 		 *  B-15 |    \        if scope is enough for destination.
1521 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1522 		 * d-C-1 | /
1523 		 *       |/         <- greater is better
1524 		 *   -C  /             if scope is not enough for destination.
1525 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1526 		 *
1527 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1528 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1529 		 * Assume B = 0 and we get C > 29.
1530 		 */
1531 		ret = __ipv6_addr_src_scope(score->addr_type);
1532 		if (ret >= dst->scope)
1533 			ret = -ret;
1534 		else
1535 			ret -= 128;	/* 30 is enough */
1536 		score->scopedist = ret;
1537 		break;
1538 	case IPV6_SADDR_RULE_PREFERRED:
1539 	    {
1540 		/* Rule 3: Avoid deprecated and optimistic addresses */
1541 		u8 avoid = IFA_F_DEPRECATED;
1542 
1543 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1544 			avoid |= IFA_F_OPTIMISTIC;
1545 		ret = ipv6_saddr_preferred(score->addr_type) ||
1546 		      !(score->ifa->flags & avoid);
1547 		break;
1548 	    }
1549 #ifdef CONFIG_IPV6_MIP6
1550 	case IPV6_SADDR_RULE_HOA:
1551 	    {
1552 		/* Rule 4: Prefer home address */
1553 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1554 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1555 		break;
1556 	    }
1557 #endif
1558 	case IPV6_SADDR_RULE_OIF:
1559 		/* Rule 5: Prefer outgoing interface */
1560 		ret = (!dst->ifindex ||
1561 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1562 		break;
1563 	case IPV6_SADDR_RULE_LABEL:
1564 		/* Rule 6: Prefer matching label */
1565 		ret = ipv6_addr_label(net,
1566 				      &score->ifa->addr, score->addr_type,
1567 				      score->ifa->idev->dev->ifindex) == dst->label;
1568 		break;
1569 	case IPV6_SADDR_RULE_PRIVACY:
1570 	    {
1571 		/* Rule 7: Prefer public address
1572 		 * Note: prefer temporary address if use_tempaddr >= 2
1573 		 */
1574 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1575 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1576 				score->ifa->idev->cnf.use_tempaddr >= 2;
1577 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1578 		break;
1579 	    }
1580 	case IPV6_SADDR_RULE_ORCHID:
1581 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1582 		 *	    non-ORCHID vs non-ORCHID
1583 		 */
1584 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1585 			ipv6_addr_orchid(dst->addr));
1586 		break;
1587 	case IPV6_SADDR_RULE_PREFIX:
1588 		/* Rule 8: Use longest matching prefix */
1589 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1590 		if (ret > score->ifa->prefix_len)
1591 			ret = score->ifa->prefix_len;
1592 		score->matchlen = ret;
1593 		break;
1594 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1595 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1596 		/* Optimistic addresses still have lower precedence than other
1597 		 * preferred addresses.
1598 		 */
1599 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1600 		break;
1601 #endif
1602 	default:
1603 		ret = 0;
1604 	}
1605 
1606 	if (ret)
1607 		__set_bit(i, score->scorebits);
1608 	score->rule = i;
1609 out:
1610 	return ret;
1611 }
1612 
1613 static int __ipv6_dev_get_saddr(struct net *net,
1614 				struct ipv6_saddr_dst *dst,
1615 				struct inet6_dev *idev,
1616 				struct ipv6_saddr_score *scores,
1617 				int hiscore_idx)
1618 {
1619 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1620 
1621 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1622 		int i;
1623 
1624 		/*
1625 		 * - Tentative Address (RFC2462 section 5.4)
1626 		 *  - A tentative address is not considered
1627 		 *    "assigned to an interface" in the traditional
1628 		 *    sense, unless it is also flagged as optimistic.
1629 		 * - Candidate Source Address (section 4)
1630 		 *  - In any case, anycast addresses, multicast
1631 		 *    addresses, and the unspecified address MUST
1632 		 *    NOT be included in a candidate set.
1633 		 */
1634 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1635 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1636 			continue;
1637 
1638 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1639 
1640 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1641 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1642 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1643 					    idev->dev->name);
1644 			continue;
1645 		}
1646 
1647 		score->rule = -1;
1648 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1649 
1650 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1651 			int minihiscore, miniscore;
1652 
1653 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1654 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1655 
1656 			if (minihiscore > miniscore) {
1657 				if (i == IPV6_SADDR_RULE_SCOPE &&
1658 				    score->scopedist > 0) {
1659 					/*
1660 					 * special case:
1661 					 * each remaining entry
1662 					 * has too small (not enough)
1663 					 * scope, because ifa entries
1664 					 * are sorted by their scope
1665 					 * values.
1666 					 */
1667 					goto out;
1668 				}
1669 				break;
1670 			} else if (minihiscore < miniscore) {
1671 				swap(hiscore, score);
1672 				hiscore_idx = 1 - hiscore_idx;
1673 
1674 				/* restore our iterator */
1675 				score->ifa = hiscore->ifa;
1676 
1677 				break;
1678 			}
1679 		}
1680 	}
1681 out:
1682 	return hiscore_idx;
1683 }
1684 
1685 static int ipv6_get_saddr_master(struct net *net,
1686 				 const struct net_device *dst_dev,
1687 				 const struct net_device *master,
1688 				 struct ipv6_saddr_dst *dst,
1689 				 struct ipv6_saddr_score *scores,
1690 				 int hiscore_idx)
1691 {
1692 	struct inet6_dev *idev;
1693 
1694 	idev = __in6_dev_get(dst_dev);
1695 	if (idev)
1696 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1697 						   scores, hiscore_idx);
1698 
1699 	idev = __in6_dev_get(master);
1700 	if (idev)
1701 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1702 						   scores, hiscore_idx);
1703 
1704 	return hiscore_idx;
1705 }
1706 
1707 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1708 		       const struct in6_addr *daddr, unsigned int prefs,
1709 		       struct in6_addr *saddr)
1710 {
1711 	struct ipv6_saddr_score scores[2], *hiscore;
1712 	struct ipv6_saddr_dst dst;
1713 	struct inet6_dev *idev;
1714 	struct net_device *dev;
1715 	int dst_type;
1716 	bool use_oif_addr = false;
1717 	int hiscore_idx = 0;
1718 	int ret = 0;
1719 
1720 	dst_type = __ipv6_addr_type(daddr);
1721 	dst.addr = daddr;
1722 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1723 	dst.scope = __ipv6_addr_src_scope(dst_type);
1724 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1725 	dst.prefs = prefs;
1726 
1727 	scores[hiscore_idx].rule = -1;
1728 	scores[hiscore_idx].ifa = NULL;
1729 
1730 	rcu_read_lock();
1731 
1732 	/* Candidate Source Address (section 4)
1733 	 *  - multicast and link-local destination address,
1734 	 *    the set of candidate source address MUST only
1735 	 *    include addresses assigned to interfaces
1736 	 *    belonging to the same link as the outgoing
1737 	 *    interface.
1738 	 * (- For site-local destination addresses, the
1739 	 *    set of candidate source addresses MUST only
1740 	 *    include addresses assigned to interfaces
1741 	 *    belonging to the same site as the outgoing
1742 	 *    interface.)
1743 	 *  - "It is RECOMMENDED that the candidate source addresses
1744 	 *    be the set of unicast addresses assigned to the
1745 	 *    interface that will be used to send to the destination
1746 	 *    (the 'outgoing' interface)." (RFC 6724)
1747 	 */
1748 	if (dst_dev) {
1749 		idev = __in6_dev_get(dst_dev);
1750 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1751 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1752 		    (idev && idev->cnf.use_oif_addrs_only)) {
1753 			use_oif_addr = true;
1754 		}
1755 	}
1756 
1757 	if (use_oif_addr) {
1758 		if (idev)
1759 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1760 	} else {
1761 		const struct net_device *master;
1762 		int master_idx = 0;
1763 
1764 		/* if dst_dev exists and is enslaved to an L3 device, then
1765 		 * prefer addresses from dst_dev and then the master over
1766 		 * any other enslaved devices in the L3 domain.
1767 		 */
1768 		master = l3mdev_master_dev_rcu(dst_dev);
1769 		if (master) {
1770 			master_idx = master->ifindex;
1771 
1772 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1773 							    master, &dst,
1774 							    scores, hiscore_idx);
1775 
1776 			if (scores[hiscore_idx].ifa)
1777 				goto out;
1778 		}
1779 
1780 		for_each_netdev_rcu(net, dev) {
1781 			/* only consider addresses on devices in the
1782 			 * same L3 domain
1783 			 */
1784 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1785 				continue;
1786 			idev = __in6_dev_get(dev);
1787 			if (!idev)
1788 				continue;
1789 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1790 		}
1791 	}
1792 
1793 out:
1794 	hiscore = &scores[hiscore_idx];
1795 	if (!hiscore->ifa)
1796 		ret = -EADDRNOTAVAIL;
1797 	else
1798 		*saddr = hiscore->ifa->addr;
1799 
1800 	rcu_read_unlock();
1801 	return ret;
1802 }
1803 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1804 
1805 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1806 		      u32 banned_flags)
1807 {
1808 	struct inet6_ifaddr *ifp;
1809 	int err = -EADDRNOTAVAIL;
1810 
1811 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1812 		if (ifp->scope > IFA_LINK)
1813 			break;
1814 		if (ifp->scope == IFA_LINK &&
1815 		    !(ifp->flags & banned_flags)) {
1816 			*addr = ifp->addr;
1817 			err = 0;
1818 			break;
1819 		}
1820 	}
1821 	return err;
1822 }
1823 
1824 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1825 		    u32 banned_flags)
1826 {
1827 	struct inet6_dev *idev;
1828 	int err = -EADDRNOTAVAIL;
1829 
1830 	rcu_read_lock();
1831 	idev = __in6_dev_get(dev);
1832 	if (idev) {
1833 		read_lock_bh(&idev->lock);
1834 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1835 		read_unlock_bh(&idev->lock);
1836 	}
1837 	rcu_read_unlock();
1838 	return err;
1839 }
1840 
1841 static int ipv6_count_addresses(const struct inet6_dev *idev)
1842 {
1843 	const struct inet6_ifaddr *ifp;
1844 	int cnt = 0;
1845 
1846 	rcu_read_lock();
1847 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1848 		cnt++;
1849 	rcu_read_unlock();
1850 	return cnt;
1851 }
1852 
1853 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1854 		  const struct net_device *dev, int strict)
1855 {
1856 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1857 				       strict, IFA_F_TENTATIVE);
1858 }
1859 EXPORT_SYMBOL(ipv6_chk_addr);
1860 
1861 /* device argument is used to find the L3 domain of interest. If
1862  * skip_dev_check is set, then the ifp device is not checked against
1863  * the passed in dev argument. So the 2 cases for addresses checks are:
1864  *   1. does the address exist in the L3 domain that dev is part of
1865  *      (skip_dev_check = true), or
1866  *
1867  *   2. does the address exist on the specific device
1868  *      (skip_dev_check = false)
1869  */
1870 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1871 			    const struct net_device *dev, bool skip_dev_check,
1872 			    int strict, u32 banned_flags)
1873 {
1874 	unsigned int hash = inet6_addr_hash(net, addr);
1875 	const struct net_device *l3mdev;
1876 	struct inet6_ifaddr *ifp;
1877 	u32 ifp_flags;
1878 
1879 	rcu_read_lock();
1880 
1881 	l3mdev = l3mdev_master_dev_rcu(dev);
1882 	if (skip_dev_check)
1883 		dev = NULL;
1884 
1885 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1886 		if (!net_eq(dev_net(ifp->idev->dev), net))
1887 			continue;
1888 
1889 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1890 			continue;
1891 
1892 		/* Decouple optimistic from tentative for evaluation here.
1893 		 * Ban optimistic addresses explicitly, when required.
1894 		 */
1895 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1896 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1897 			    : ifp->flags;
1898 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1899 		    !(ifp_flags&banned_flags) &&
1900 		    (!dev || ifp->idev->dev == dev ||
1901 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1902 			rcu_read_unlock();
1903 			return 1;
1904 		}
1905 	}
1906 
1907 	rcu_read_unlock();
1908 	return 0;
1909 }
1910 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1911 
1912 
1913 /* Compares an address/prefix_len with addresses on device @dev.
1914  * If one is found it returns true.
1915  */
1916 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1917 	const unsigned int prefix_len, struct net_device *dev)
1918 {
1919 	const struct inet6_ifaddr *ifa;
1920 	const struct inet6_dev *idev;
1921 	bool ret = false;
1922 
1923 	rcu_read_lock();
1924 	idev = __in6_dev_get(dev);
1925 	if (idev) {
1926 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1927 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1928 			if (ret)
1929 				break;
1930 		}
1931 	}
1932 	rcu_read_unlock();
1933 
1934 	return ret;
1935 }
1936 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1937 
1938 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1939 {
1940 	const struct inet6_ifaddr *ifa;
1941 	const struct inet6_dev *idev;
1942 	int	onlink;
1943 
1944 	onlink = 0;
1945 	rcu_read_lock();
1946 	idev = __in6_dev_get(dev);
1947 	if (idev) {
1948 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1949 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1950 						   ifa->prefix_len);
1951 			if (onlink)
1952 				break;
1953 		}
1954 	}
1955 	rcu_read_unlock();
1956 	return onlink;
1957 }
1958 EXPORT_SYMBOL(ipv6_chk_prefix);
1959 
1960 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1961 				     struct net_device *dev, int strict)
1962 {
1963 	unsigned int hash = inet6_addr_hash(net, addr);
1964 	struct inet6_ifaddr *ifp, *result = NULL;
1965 
1966 	rcu_read_lock();
1967 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1968 		if (!net_eq(dev_net(ifp->idev->dev), net))
1969 			continue;
1970 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1971 			if (!dev || ifp->idev->dev == dev ||
1972 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1973 				result = ifp;
1974 				in6_ifa_hold(ifp);
1975 				break;
1976 			}
1977 		}
1978 	}
1979 	rcu_read_unlock();
1980 
1981 	return result;
1982 }
1983 
1984 /* Gets referenced address, destroys ifaddr */
1985 
1986 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1987 {
1988 	if (dad_failed)
1989 		ifp->flags |= IFA_F_DADFAILED;
1990 
1991 	if (ifp->flags&IFA_F_TEMPORARY) {
1992 		struct inet6_ifaddr *ifpub;
1993 		spin_lock_bh(&ifp->lock);
1994 		ifpub = ifp->ifpub;
1995 		if (ifpub) {
1996 			in6_ifa_hold(ifpub);
1997 			spin_unlock_bh(&ifp->lock);
1998 			ipv6_create_tempaddr(ifpub, ifp, true);
1999 			in6_ifa_put(ifpub);
2000 		} else {
2001 			spin_unlock_bh(&ifp->lock);
2002 		}
2003 		ipv6_del_addr(ifp);
2004 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2005 		spin_lock_bh(&ifp->lock);
2006 		addrconf_del_dad_work(ifp);
2007 		ifp->flags |= IFA_F_TENTATIVE;
2008 		if (dad_failed)
2009 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2010 		spin_unlock_bh(&ifp->lock);
2011 		if (dad_failed)
2012 			ipv6_ifa_notify(0, ifp);
2013 		in6_ifa_put(ifp);
2014 	} else {
2015 		ipv6_del_addr(ifp);
2016 	}
2017 }
2018 
2019 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2020 {
2021 	int err = -ENOENT;
2022 
2023 	spin_lock_bh(&ifp->lock);
2024 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2025 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2026 		err = 0;
2027 	}
2028 	spin_unlock_bh(&ifp->lock);
2029 
2030 	return err;
2031 }
2032 
2033 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2034 {
2035 	struct inet6_dev *idev = ifp->idev;
2036 	struct net *net = dev_net(ifp->idev->dev);
2037 
2038 	if (addrconf_dad_end(ifp)) {
2039 		in6_ifa_put(ifp);
2040 		return;
2041 	}
2042 
2043 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2044 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2045 
2046 	spin_lock_bh(&ifp->lock);
2047 
2048 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2049 		struct in6_addr new_addr;
2050 		struct inet6_ifaddr *ifp2;
2051 		int retries = ifp->stable_privacy_retry + 1;
2052 		struct ifa6_config cfg = {
2053 			.pfx = &new_addr,
2054 			.plen = ifp->prefix_len,
2055 			.ifa_flags = ifp->flags,
2056 			.valid_lft = ifp->valid_lft,
2057 			.preferred_lft = ifp->prefered_lft,
2058 			.scope = ifp->scope,
2059 		};
2060 
2061 		if (retries > net->ipv6.sysctl.idgen_retries) {
2062 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2063 					     ifp->idev->dev->name);
2064 			goto errdad;
2065 		}
2066 
2067 		new_addr = ifp->addr;
2068 		if (ipv6_generate_stable_address(&new_addr, retries,
2069 						 idev))
2070 			goto errdad;
2071 
2072 		spin_unlock_bh(&ifp->lock);
2073 
2074 		if (idev->cnf.max_addresses &&
2075 		    ipv6_count_addresses(idev) >=
2076 		    idev->cnf.max_addresses)
2077 			goto lock_errdad;
2078 
2079 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2080 				     ifp->idev->dev->name);
2081 
2082 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2083 		if (IS_ERR(ifp2))
2084 			goto lock_errdad;
2085 
2086 		spin_lock_bh(&ifp2->lock);
2087 		ifp2->stable_privacy_retry = retries;
2088 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2089 		spin_unlock_bh(&ifp2->lock);
2090 
2091 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2092 		in6_ifa_put(ifp2);
2093 lock_errdad:
2094 		spin_lock_bh(&ifp->lock);
2095 	}
2096 
2097 errdad:
2098 	/* transition from _POSTDAD to _ERRDAD */
2099 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2100 	spin_unlock_bh(&ifp->lock);
2101 
2102 	addrconf_mod_dad_work(ifp, 0);
2103 	in6_ifa_put(ifp);
2104 }
2105 
2106 /* Join to solicited addr multicast group.
2107  * caller must hold RTNL */
2108 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2109 {
2110 	struct in6_addr maddr;
2111 
2112 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2113 		return;
2114 
2115 	addrconf_addr_solict_mult(addr, &maddr);
2116 	ipv6_dev_mc_inc(dev, &maddr);
2117 }
2118 
2119 /* caller must hold RTNL */
2120 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2121 {
2122 	struct in6_addr maddr;
2123 
2124 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2125 		return;
2126 
2127 	addrconf_addr_solict_mult(addr, &maddr);
2128 	__ipv6_dev_mc_dec(idev, &maddr);
2129 }
2130 
2131 /* caller must hold RTNL */
2132 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2133 {
2134 	struct in6_addr addr;
2135 
2136 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2137 		return;
2138 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2139 	if (ipv6_addr_any(&addr))
2140 		return;
2141 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2142 }
2143 
2144 /* caller must hold RTNL */
2145 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2146 {
2147 	struct in6_addr addr;
2148 
2149 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2150 		return;
2151 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2152 	if (ipv6_addr_any(&addr))
2153 		return;
2154 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2155 }
2156 
2157 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2158 {
2159 	switch (dev->addr_len) {
2160 	case ETH_ALEN:
2161 		memcpy(eui, dev->dev_addr, 3);
2162 		eui[3] = 0xFF;
2163 		eui[4] = 0xFE;
2164 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2165 		break;
2166 	case EUI64_ADDR_LEN:
2167 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2168 		eui[0] ^= 2;
2169 		break;
2170 	default:
2171 		return -1;
2172 	}
2173 
2174 	return 0;
2175 }
2176 
2177 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2178 {
2179 	union fwnet_hwaddr *ha;
2180 
2181 	if (dev->addr_len != FWNET_ALEN)
2182 		return -1;
2183 
2184 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2185 
2186 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2187 	eui[0] ^= 2;
2188 	return 0;
2189 }
2190 
2191 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2192 {
2193 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2194 	if (dev->addr_len != ARCNET_ALEN)
2195 		return -1;
2196 	memset(eui, 0, 7);
2197 	eui[7] = *(u8 *)dev->dev_addr;
2198 	return 0;
2199 }
2200 
2201 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2202 {
2203 	if (dev->addr_len != INFINIBAND_ALEN)
2204 		return -1;
2205 	memcpy(eui, dev->dev_addr + 12, 8);
2206 	eui[0] |= 2;
2207 	return 0;
2208 }
2209 
2210 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2211 {
2212 	if (addr == 0)
2213 		return -1;
2214 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2215 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2216 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2217 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2218 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2219 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2220 	eui[1] = 0;
2221 	eui[2] = 0x5E;
2222 	eui[3] = 0xFE;
2223 	memcpy(eui + 4, &addr, 4);
2224 	return 0;
2225 }
2226 
2227 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2228 {
2229 	if (dev->priv_flags & IFF_ISATAP)
2230 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2231 	return -1;
2232 }
2233 
2234 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2235 {
2236 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2237 }
2238 
2239 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2240 {
2241 	memcpy(eui, dev->perm_addr, 3);
2242 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2243 	eui[3] = 0xFF;
2244 	eui[4] = 0xFE;
2245 	eui[0] ^= 2;
2246 	return 0;
2247 }
2248 
2249 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2250 {
2251 	switch (dev->type) {
2252 	case ARPHRD_ETHER:
2253 	case ARPHRD_FDDI:
2254 		return addrconf_ifid_eui48(eui, dev);
2255 	case ARPHRD_ARCNET:
2256 		return addrconf_ifid_arcnet(eui, dev);
2257 	case ARPHRD_INFINIBAND:
2258 		return addrconf_ifid_infiniband(eui, dev);
2259 	case ARPHRD_SIT:
2260 		return addrconf_ifid_sit(eui, dev);
2261 	case ARPHRD_IPGRE:
2262 	case ARPHRD_TUNNEL:
2263 		return addrconf_ifid_gre(eui, dev);
2264 	case ARPHRD_6LOWPAN:
2265 		return addrconf_ifid_6lowpan(eui, dev);
2266 	case ARPHRD_IEEE1394:
2267 		return addrconf_ifid_ieee1394(eui, dev);
2268 	case ARPHRD_TUNNEL6:
2269 	case ARPHRD_IP6GRE:
2270 	case ARPHRD_RAWIP:
2271 		return addrconf_ifid_ip6tnl(eui, dev);
2272 	}
2273 	return -1;
2274 }
2275 
2276 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2277 {
2278 	int err = -1;
2279 	struct inet6_ifaddr *ifp;
2280 
2281 	read_lock_bh(&idev->lock);
2282 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2283 		if (ifp->scope > IFA_LINK)
2284 			break;
2285 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2286 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2287 			err = 0;
2288 			break;
2289 		}
2290 	}
2291 	read_unlock_bh(&idev->lock);
2292 	return err;
2293 }
2294 
2295 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2296 static void ipv6_regen_rndid(struct inet6_dev *idev)
2297 {
2298 regen:
2299 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2300 	idev->rndid[0] &= ~0x02;
2301 
2302 	/*
2303 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2304 	 * check if generated address is not inappropriate
2305 	 *
2306 	 *  - Reserved subnet anycast (RFC 2526)
2307 	 *	11111101 11....11 1xxxxxxx
2308 	 *  - ISATAP (RFC4214) 6.1
2309 	 *	00-00-5E-FE-xx-xx-xx-xx
2310 	 *  - value 0
2311 	 *  - XXX: already assigned to an address on the device
2312 	 */
2313 	if (idev->rndid[0] == 0xfd &&
2314 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2315 	    (idev->rndid[7]&0x80))
2316 		goto regen;
2317 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2318 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2319 			goto regen;
2320 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2321 			goto regen;
2322 	}
2323 }
2324 
2325 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2326 {
2327 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2328 		ipv6_regen_rndid(idev);
2329 }
2330 
2331 /*
2332  *	Add prefix route.
2333  */
2334 
2335 static void
2336 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2337 		      struct net_device *dev, unsigned long expires,
2338 		      u32 flags, gfp_t gfp_flags)
2339 {
2340 	struct fib6_config cfg = {
2341 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2342 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2343 		.fc_ifindex = dev->ifindex,
2344 		.fc_expires = expires,
2345 		.fc_dst_len = plen,
2346 		.fc_flags = RTF_UP | flags,
2347 		.fc_nlinfo.nl_net = dev_net(dev),
2348 		.fc_protocol = RTPROT_KERNEL,
2349 		.fc_type = RTN_UNICAST,
2350 	};
2351 
2352 	cfg.fc_dst = *pfx;
2353 
2354 	/* Prevent useless cloning on PtP SIT.
2355 	   This thing is done here expecting that the whole
2356 	   class of non-broadcast devices need not cloning.
2357 	 */
2358 #if IS_ENABLED(CONFIG_IPV6_SIT)
2359 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2360 		cfg.fc_flags |= RTF_NONEXTHOP;
2361 #endif
2362 
2363 	ip6_route_add(&cfg, gfp_flags, NULL);
2364 }
2365 
2366 
2367 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2368 						  int plen,
2369 						  const struct net_device *dev,
2370 						  u32 flags, u32 noflags)
2371 {
2372 	struct fib6_node *fn;
2373 	struct fib6_info *rt = NULL;
2374 	struct fib6_table *table;
2375 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2376 
2377 	table = fib6_get_table(dev_net(dev), tb_id);
2378 	if (!table)
2379 		return NULL;
2380 
2381 	rcu_read_lock();
2382 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2383 	if (!fn)
2384 		goto out;
2385 
2386 	for_each_fib6_node_rt_rcu(fn) {
2387 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
2388 			continue;
2389 		if ((rt->fib6_flags & flags) != flags)
2390 			continue;
2391 		if ((rt->fib6_flags & noflags) != 0)
2392 			continue;
2393 		if (!fib6_info_hold_safe(rt))
2394 			continue;
2395 		break;
2396 	}
2397 out:
2398 	rcu_read_unlock();
2399 	return rt;
2400 }
2401 
2402 
2403 /* Create "default" multicast route to the interface */
2404 
2405 static void addrconf_add_mroute(struct net_device *dev)
2406 {
2407 	struct fib6_config cfg = {
2408 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2409 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2410 		.fc_ifindex = dev->ifindex,
2411 		.fc_dst_len = 8,
2412 		.fc_flags = RTF_UP,
2413 		.fc_type = RTN_UNICAST,
2414 		.fc_nlinfo.nl_net = dev_net(dev),
2415 	};
2416 
2417 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2418 
2419 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2420 }
2421 
2422 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2423 {
2424 	struct inet6_dev *idev;
2425 
2426 	ASSERT_RTNL();
2427 
2428 	idev = ipv6_find_idev(dev);
2429 	if (!idev)
2430 		return ERR_PTR(-ENOBUFS);
2431 
2432 	if (idev->cnf.disable_ipv6)
2433 		return ERR_PTR(-EACCES);
2434 
2435 	/* Add default multicast route */
2436 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2437 		addrconf_add_mroute(dev);
2438 
2439 	return idev;
2440 }
2441 
2442 static void manage_tempaddrs(struct inet6_dev *idev,
2443 			     struct inet6_ifaddr *ifp,
2444 			     __u32 valid_lft, __u32 prefered_lft,
2445 			     bool create, unsigned long now)
2446 {
2447 	u32 flags;
2448 	struct inet6_ifaddr *ift;
2449 
2450 	read_lock_bh(&idev->lock);
2451 	/* update all temporary addresses in the list */
2452 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2453 		int age, max_valid, max_prefered;
2454 
2455 		if (ifp != ift->ifpub)
2456 			continue;
2457 
2458 		/* RFC 4941 section 3.3:
2459 		 * If a received option will extend the lifetime of a public
2460 		 * address, the lifetimes of temporary addresses should
2461 		 * be extended, subject to the overall constraint that no
2462 		 * temporary addresses should ever remain "valid" or "preferred"
2463 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2464 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2465 		 */
2466 		age = (now - ift->cstamp) / HZ;
2467 		max_valid = idev->cnf.temp_valid_lft - age;
2468 		if (max_valid < 0)
2469 			max_valid = 0;
2470 
2471 		max_prefered = idev->cnf.temp_prefered_lft -
2472 			       idev->desync_factor - age;
2473 		if (max_prefered < 0)
2474 			max_prefered = 0;
2475 
2476 		if (valid_lft > max_valid)
2477 			valid_lft = max_valid;
2478 
2479 		if (prefered_lft > max_prefered)
2480 			prefered_lft = max_prefered;
2481 
2482 		spin_lock(&ift->lock);
2483 		flags = ift->flags;
2484 		ift->valid_lft = valid_lft;
2485 		ift->prefered_lft = prefered_lft;
2486 		ift->tstamp = now;
2487 		if (prefered_lft > 0)
2488 			ift->flags &= ~IFA_F_DEPRECATED;
2489 
2490 		spin_unlock(&ift->lock);
2491 		if (!(flags&IFA_F_TENTATIVE))
2492 			ipv6_ifa_notify(0, ift);
2493 	}
2494 
2495 	if ((create || list_empty(&idev->tempaddr_list)) &&
2496 	    idev->cnf.use_tempaddr > 0) {
2497 		/* When a new public address is created as described
2498 		 * in [ADDRCONF], also create a new temporary address.
2499 		 * Also create a temporary address if it's enabled but
2500 		 * no temporary address currently exists.
2501 		 */
2502 		read_unlock_bh(&idev->lock);
2503 		ipv6_create_tempaddr(ifp, NULL, false);
2504 	} else {
2505 		read_unlock_bh(&idev->lock);
2506 	}
2507 }
2508 
2509 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2510 {
2511 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2512 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2513 }
2514 
2515 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2516 				 const struct prefix_info *pinfo,
2517 				 struct inet6_dev *in6_dev,
2518 				 const struct in6_addr *addr, int addr_type,
2519 				 u32 addr_flags, bool sllao, bool tokenized,
2520 				 __u32 valid_lft, u32 prefered_lft)
2521 {
2522 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2523 	int create = 0, update_lft = 0;
2524 
2525 	if (!ifp && valid_lft) {
2526 		int max_addresses = in6_dev->cnf.max_addresses;
2527 		struct ifa6_config cfg = {
2528 			.pfx = addr,
2529 			.plen = pinfo->prefix_len,
2530 			.ifa_flags = addr_flags,
2531 			.valid_lft = valid_lft,
2532 			.preferred_lft = prefered_lft,
2533 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2534 		};
2535 
2536 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2537 		if ((net->ipv6.devconf_all->optimistic_dad ||
2538 		     in6_dev->cnf.optimistic_dad) &&
2539 		    !net->ipv6.devconf_all->forwarding && sllao)
2540 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2541 #endif
2542 
2543 		/* Do not allow to create too much of autoconfigured
2544 		 * addresses; this would be too easy way to crash kernel.
2545 		 */
2546 		if (!max_addresses ||
2547 		    ipv6_count_addresses(in6_dev) < max_addresses)
2548 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2549 
2550 		if (IS_ERR_OR_NULL(ifp))
2551 			return -1;
2552 
2553 		create = 1;
2554 		spin_lock_bh(&ifp->lock);
2555 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2556 		ifp->cstamp = jiffies;
2557 		ifp->tokenized = tokenized;
2558 		spin_unlock_bh(&ifp->lock);
2559 		addrconf_dad_start(ifp);
2560 	}
2561 
2562 	if (ifp) {
2563 		u32 flags;
2564 		unsigned long now;
2565 		u32 stored_lft;
2566 
2567 		/* update lifetime (RFC2462 5.5.3 e) */
2568 		spin_lock_bh(&ifp->lock);
2569 		now = jiffies;
2570 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2571 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2572 		else
2573 			stored_lft = 0;
2574 		if (!create && stored_lft) {
2575 			const u32 minimum_lft = min_t(u32,
2576 				stored_lft, MIN_VALID_LIFETIME);
2577 			valid_lft = max(valid_lft, minimum_lft);
2578 
2579 			/* RFC4862 Section 5.5.3e:
2580 			 * "Note that the preferred lifetime of the
2581 			 *  corresponding address is always reset to
2582 			 *  the Preferred Lifetime in the received
2583 			 *  Prefix Information option, regardless of
2584 			 *  whether the valid lifetime is also reset or
2585 			 *  ignored."
2586 			 *
2587 			 * So we should always update prefered_lft here.
2588 			 */
2589 			update_lft = 1;
2590 		}
2591 
2592 		if (update_lft) {
2593 			ifp->valid_lft = valid_lft;
2594 			ifp->prefered_lft = prefered_lft;
2595 			ifp->tstamp = now;
2596 			flags = ifp->flags;
2597 			ifp->flags &= ~IFA_F_DEPRECATED;
2598 			spin_unlock_bh(&ifp->lock);
2599 
2600 			if (!(flags&IFA_F_TENTATIVE))
2601 				ipv6_ifa_notify(0, ifp);
2602 		} else
2603 			spin_unlock_bh(&ifp->lock);
2604 
2605 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2606 				 create, now);
2607 
2608 		in6_ifa_put(ifp);
2609 		addrconf_verify();
2610 	}
2611 
2612 	return 0;
2613 }
2614 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2615 
2616 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2617 {
2618 	struct prefix_info *pinfo;
2619 	__u32 valid_lft;
2620 	__u32 prefered_lft;
2621 	int addr_type, err;
2622 	u32 addr_flags = 0;
2623 	struct inet6_dev *in6_dev;
2624 	struct net *net = dev_net(dev);
2625 
2626 	pinfo = (struct prefix_info *) opt;
2627 
2628 	if (len < sizeof(struct prefix_info)) {
2629 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2630 		return;
2631 	}
2632 
2633 	/*
2634 	 *	Validation checks ([ADDRCONF], page 19)
2635 	 */
2636 
2637 	addr_type = ipv6_addr_type(&pinfo->prefix);
2638 
2639 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2640 		return;
2641 
2642 	valid_lft = ntohl(pinfo->valid);
2643 	prefered_lft = ntohl(pinfo->prefered);
2644 
2645 	if (prefered_lft > valid_lft) {
2646 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2647 		return;
2648 	}
2649 
2650 	in6_dev = in6_dev_get(dev);
2651 
2652 	if (!in6_dev) {
2653 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2654 				    dev->name);
2655 		return;
2656 	}
2657 
2658 	/*
2659 	 *	Two things going on here:
2660 	 *	1) Add routes for on-link prefixes
2661 	 *	2) Configure prefixes with the auto flag set
2662 	 */
2663 
2664 	if (pinfo->onlink) {
2665 		struct fib6_info *rt;
2666 		unsigned long rt_expires;
2667 
2668 		/* Avoid arithmetic overflow. Really, we could
2669 		 * save rt_expires in seconds, likely valid_lft,
2670 		 * but it would require division in fib gc, that it
2671 		 * not good.
2672 		 */
2673 		if (HZ > USER_HZ)
2674 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2675 		else
2676 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2677 
2678 		if (addrconf_finite_timeout(rt_expires))
2679 			rt_expires *= HZ;
2680 
2681 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2682 					       pinfo->prefix_len,
2683 					       dev,
2684 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2685 					       RTF_GATEWAY | RTF_DEFAULT);
2686 
2687 		if (rt) {
2688 			/* Autoconf prefix route */
2689 			if (valid_lft == 0) {
2690 				ip6_del_rt(net, rt);
2691 				rt = NULL;
2692 			} else if (addrconf_finite_timeout(rt_expires)) {
2693 				/* not infinity */
2694 				fib6_set_expires(rt, jiffies + rt_expires);
2695 			} else {
2696 				fib6_clean_expires(rt);
2697 			}
2698 		} else if (valid_lft) {
2699 			clock_t expires = 0;
2700 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2701 			if (addrconf_finite_timeout(rt_expires)) {
2702 				/* not infinity */
2703 				flags |= RTF_EXPIRES;
2704 				expires = jiffies_to_clock_t(rt_expires);
2705 			}
2706 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2707 					      0, dev, expires, flags,
2708 					      GFP_ATOMIC);
2709 		}
2710 		fib6_info_release(rt);
2711 	}
2712 
2713 	/* Try to figure out our local address for this prefix */
2714 
2715 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2716 		struct in6_addr addr;
2717 		bool tokenized = false, dev_addr_generated = false;
2718 
2719 		if (pinfo->prefix_len == 64) {
2720 			memcpy(&addr, &pinfo->prefix, 8);
2721 
2722 			if (!ipv6_addr_any(&in6_dev->token)) {
2723 				read_lock_bh(&in6_dev->lock);
2724 				memcpy(addr.s6_addr + 8,
2725 				       in6_dev->token.s6_addr + 8, 8);
2726 				read_unlock_bh(&in6_dev->lock);
2727 				tokenized = true;
2728 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2729 				   !ipv6_generate_stable_address(&addr, 0,
2730 								 in6_dev)) {
2731 				addr_flags |= IFA_F_STABLE_PRIVACY;
2732 				goto ok;
2733 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2734 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2735 				goto put;
2736 			} else {
2737 				dev_addr_generated = true;
2738 			}
2739 			goto ok;
2740 		}
2741 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2742 				    pinfo->prefix_len);
2743 		goto put;
2744 
2745 ok:
2746 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2747 						   &addr, addr_type,
2748 						   addr_flags, sllao,
2749 						   tokenized, valid_lft,
2750 						   prefered_lft);
2751 		if (err)
2752 			goto put;
2753 
2754 		/* Ignore error case here because previous prefix add addr was
2755 		 * successful which will be notified.
2756 		 */
2757 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2758 					      addr_type, addr_flags, sllao,
2759 					      tokenized, valid_lft,
2760 					      prefered_lft,
2761 					      dev_addr_generated);
2762 	}
2763 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2764 put:
2765 	in6_dev_put(in6_dev);
2766 }
2767 
2768 /*
2769  *	Set destination address.
2770  *	Special case for SIT interfaces where we create a new "virtual"
2771  *	device.
2772  */
2773 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2774 {
2775 	struct in6_ifreq ireq;
2776 	struct net_device *dev;
2777 	int err = -EINVAL;
2778 
2779 	rtnl_lock();
2780 
2781 	err = -EFAULT;
2782 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2783 		goto err_exit;
2784 
2785 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2786 
2787 	err = -ENODEV;
2788 	if (!dev)
2789 		goto err_exit;
2790 
2791 #if IS_ENABLED(CONFIG_IPV6_SIT)
2792 	if (dev->type == ARPHRD_SIT) {
2793 		const struct net_device_ops *ops = dev->netdev_ops;
2794 		struct ifreq ifr;
2795 		struct ip_tunnel_parm p;
2796 
2797 		err = -EADDRNOTAVAIL;
2798 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2799 			goto err_exit;
2800 
2801 		memset(&p, 0, sizeof(p));
2802 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2803 		p.iph.saddr = 0;
2804 		p.iph.version = 4;
2805 		p.iph.ihl = 5;
2806 		p.iph.protocol = IPPROTO_IPV6;
2807 		p.iph.ttl = 64;
2808 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2809 
2810 		if (ops->ndo_do_ioctl) {
2811 			mm_segment_t oldfs = get_fs();
2812 
2813 			set_fs(KERNEL_DS);
2814 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2815 			set_fs(oldfs);
2816 		} else
2817 			err = -EOPNOTSUPP;
2818 
2819 		if (err == 0) {
2820 			err = -ENOBUFS;
2821 			dev = __dev_get_by_name(net, p.name);
2822 			if (!dev)
2823 				goto err_exit;
2824 			err = dev_open(dev, NULL);
2825 		}
2826 	}
2827 #endif
2828 
2829 err_exit:
2830 	rtnl_unlock();
2831 	return err;
2832 }
2833 
2834 static int ipv6_mc_config(struct sock *sk, bool join,
2835 			  const struct in6_addr *addr, int ifindex)
2836 {
2837 	int ret;
2838 
2839 	ASSERT_RTNL();
2840 
2841 	lock_sock(sk);
2842 	if (join)
2843 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2844 	else
2845 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2846 	release_sock(sk);
2847 
2848 	return ret;
2849 }
2850 
2851 /*
2852  *	Manual configuration of address on an interface
2853  */
2854 static int inet6_addr_add(struct net *net, int ifindex,
2855 			  struct ifa6_config *cfg,
2856 			  struct netlink_ext_ack *extack)
2857 {
2858 	struct inet6_ifaddr *ifp;
2859 	struct inet6_dev *idev;
2860 	struct net_device *dev;
2861 	unsigned long timeout;
2862 	clock_t expires;
2863 	u32 flags;
2864 
2865 	ASSERT_RTNL();
2866 
2867 	if (cfg->plen > 128)
2868 		return -EINVAL;
2869 
2870 	/* check the lifetime */
2871 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2872 		return -EINVAL;
2873 
2874 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2875 		return -EINVAL;
2876 
2877 	dev = __dev_get_by_index(net, ifindex);
2878 	if (!dev)
2879 		return -ENODEV;
2880 
2881 	idev = addrconf_add_dev(dev);
2882 	if (IS_ERR(idev))
2883 		return PTR_ERR(idev);
2884 
2885 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2886 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2887 					 true, cfg->pfx, ifindex);
2888 
2889 		if (ret < 0)
2890 			return ret;
2891 	}
2892 
2893 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2894 
2895 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2896 	if (addrconf_finite_timeout(timeout)) {
2897 		expires = jiffies_to_clock_t(timeout * HZ);
2898 		cfg->valid_lft = timeout;
2899 		flags = RTF_EXPIRES;
2900 	} else {
2901 		expires = 0;
2902 		flags = 0;
2903 		cfg->ifa_flags |= IFA_F_PERMANENT;
2904 	}
2905 
2906 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2907 	if (addrconf_finite_timeout(timeout)) {
2908 		if (timeout == 0)
2909 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2910 		cfg->preferred_lft = timeout;
2911 	}
2912 
2913 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2914 	if (!IS_ERR(ifp)) {
2915 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2916 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2917 					      ifp->rt_priority, dev, expires,
2918 					      flags, GFP_KERNEL);
2919 		}
2920 
2921 		/* Send a netlink notification if DAD is enabled and
2922 		 * optimistic flag is not set
2923 		 */
2924 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2925 			ipv6_ifa_notify(0, ifp);
2926 		/*
2927 		 * Note that section 3.1 of RFC 4429 indicates
2928 		 * that the Optimistic flag should not be set for
2929 		 * manually configured addresses
2930 		 */
2931 		addrconf_dad_start(ifp);
2932 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2933 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2934 					 cfg->preferred_lft, true, jiffies);
2935 		in6_ifa_put(ifp);
2936 		addrconf_verify_rtnl();
2937 		return 0;
2938 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2939 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2940 			       cfg->pfx, ifindex);
2941 	}
2942 
2943 	return PTR_ERR(ifp);
2944 }
2945 
2946 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2947 			  const struct in6_addr *pfx, unsigned int plen)
2948 {
2949 	struct inet6_ifaddr *ifp;
2950 	struct inet6_dev *idev;
2951 	struct net_device *dev;
2952 
2953 	if (plen > 128)
2954 		return -EINVAL;
2955 
2956 	dev = __dev_get_by_index(net, ifindex);
2957 	if (!dev)
2958 		return -ENODEV;
2959 
2960 	idev = __in6_dev_get(dev);
2961 	if (!idev)
2962 		return -ENXIO;
2963 
2964 	read_lock_bh(&idev->lock);
2965 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2966 		if (ifp->prefix_len == plen &&
2967 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2968 			in6_ifa_hold(ifp);
2969 			read_unlock_bh(&idev->lock);
2970 
2971 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2972 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2973 				manage_tempaddrs(idev, ifp, 0, 0, false,
2974 						 jiffies);
2975 			ipv6_del_addr(ifp);
2976 			addrconf_verify_rtnl();
2977 			if (ipv6_addr_is_multicast(pfx)) {
2978 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2979 					       false, pfx, dev->ifindex);
2980 			}
2981 			return 0;
2982 		}
2983 	}
2984 	read_unlock_bh(&idev->lock);
2985 	return -EADDRNOTAVAIL;
2986 }
2987 
2988 
2989 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2990 {
2991 	struct ifa6_config cfg = {
2992 		.ifa_flags = IFA_F_PERMANENT,
2993 		.preferred_lft = INFINITY_LIFE_TIME,
2994 		.valid_lft = INFINITY_LIFE_TIME,
2995 	};
2996 	struct in6_ifreq ireq;
2997 	int err;
2998 
2999 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3000 		return -EPERM;
3001 
3002 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3003 		return -EFAULT;
3004 
3005 	cfg.pfx = &ireq.ifr6_addr;
3006 	cfg.plen = ireq.ifr6_prefixlen;
3007 
3008 	rtnl_lock();
3009 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3010 	rtnl_unlock();
3011 	return err;
3012 }
3013 
3014 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3015 {
3016 	struct in6_ifreq ireq;
3017 	int err;
3018 
3019 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3020 		return -EPERM;
3021 
3022 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3023 		return -EFAULT;
3024 
3025 	rtnl_lock();
3026 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3027 			     ireq.ifr6_prefixlen);
3028 	rtnl_unlock();
3029 	return err;
3030 }
3031 
3032 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3033 		     int plen, int scope)
3034 {
3035 	struct inet6_ifaddr *ifp;
3036 	struct ifa6_config cfg = {
3037 		.pfx = addr,
3038 		.plen = plen,
3039 		.ifa_flags = IFA_F_PERMANENT,
3040 		.valid_lft = INFINITY_LIFE_TIME,
3041 		.preferred_lft = INFINITY_LIFE_TIME,
3042 		.scope = scope
3043 	};
3044 
3045 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3046 	if (!IS_ERR(ifp)) {
3047 		spin_lock_bh(&ifp->lock);
3048 		ifp->flags &= ~IFA_F_TENTATIVE;
3049 		spin_unlock_bh(&ifp->lock);
3050 		rt_genid_bump_ipv6(dev_net(idev->dev));
3051 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3052 		in6_ifa_put(ifp);
3053 	}
3054 }
3055 
3056 #if IS_ENABLED(CONFIG_IPV6_SIT)
3057 static void sit_add_v4_addrs(struct inet6_dev *idev)
3058 {
3059 	struct in6_addr addr;
3060 	struct net_device *dev;
3061 	struct net *net = dev_net(idev->dev);
3062 	int scope, plen;
3063 	u32 pflags = 0;
3064 
3065 	ASSERT_RTNL();
3066 
3067 	memset(&addr, 0, sizeof(struct in6_addr));
3068 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3069 
3070 	if (idev->dev->flags&IFF_POINTOPOINT) {
3071 		addr.s6_addr32[0] = htonl(0xfe800000);
3072 		scope = IFA_LINK;
3073 		plen = 64;
3074 	} else {
3075 		scope = IPV6_ADDR_COMPATv4;
3076 		plen = 96;
3077 		pflags |= RTF_NONEXTHOP;
3078 	}
3079 
3080 	if (addr.s6_addr32[3]) {
3081 		add_addr(idev, &addr, plen, scope);
3082 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3083 				      GFP_KERNEL);
3084 		return;
3085 	}
3086 
3087 	for_each_netdev(net, dev) {
3088 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3089 		if (in_dev && (dev->flags & IFF_UP)) {
3090 			struct in_ifaddr *ifa;
3091 
3092 			int flag = scope;
3093 
3094 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3095 
3096 				addr.s6_addr32[3] = ifa->ifa_local;
3097 
3098 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3099 					continue;
3100 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3101 					if (idev->dev->flags&IFF_POINTOPOINT)
3102 						continue;
3103 					flag |= IFA_HOST;
3104 				}
3105 
3106 				add_addr(idev, &addr, plen, flag);
3107 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3108 						      0, pflags, GFP_KERNEL);
3109 			}
3110 		}
3111 	}
3112 }
3113 #endif
3114 
3115 static void init_loopback(struct net_device *dev)
3116 {
3117 	struct inet6_dev  *idev;
3118 
3119 	/* ::1 */
3120 
3121 	ASSERT_RTNL();
3122 
3123 	idev = ipv6_find_idev(dev);
3124 	if (!idev) {
3125 		pr_debug("%s: add_dev failed\n", __func__);
3126 		return;
3127 	}
3128 
3129 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3130 }
3131 
3132 void addrconf_add_linklocal(struct inet6_dev *idev,
3133 			    const struct in6_addr *addr, u32 flags)
3134 {
3135 	struct ifa6_config cfg = {
3136 		.pfx = addr,
3137 		.plen = 64,
3138 		.ifa_flags = flags | IFA_F_PERMANENT,
3139 		.valid_lft = INFINITY_LIFE_TIME,
3140 		.preferred_lft = INFINITY_LIFE_TIME,
3141 		.scope = IFA_LINK
3142 	};
3143 	struct inet6_ifaddr *ifp;
3144 
3145 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3146 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3147 	     idev->cnf.optimistic_dad) &&
3148 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3149 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3150 #endif
3151 
3152 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3153 	if (!IS_ERR(ifp)) {
3154 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3155 				      0, 0, GFP_ATOMIC);
3156 		addrconf_dad_start(ifp);
3157 		in6_ifa_put(ifp);
3158 	}
3159 }
3160 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3161 
3162 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3163 {
3164 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3165 		return true;
3166 
3167 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3168 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3169 		return true;
3170 
3171 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3172 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3173 		return true;
3174 
3175 	return false;
3176 }
3177 
3178 static int ipv6_generate_stable_address(struct in6_addr *address,
3179 					u8 dad_count,
3180 					const struct inet6_dev *idev)
3181 {
3182 	static DEFINE_SPINLOCK(lock);
3183 	static __u32 digest[SHA_DIGEST_WORDS];
3184 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3185 
3186 	static union {
3187 		char __data[SHA_MESSAGE_BYTES];
3188 		struct {
3189 			struct in6_addr secret;
3190 			__be32 prefix[2];
3191 			unsigned char hwaddr[MAX_ADDR_LEN];
3192 			u8 dad_count;
3193 		} __packed;
3194 	} data;
3195 
3196 	struct in6_addr secret;
3197 	struct in6_addr temp;
3198 	struct net *net = dev_net(idev->dev);
3199 
3200 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3201 
3202 	if (idev->cnf.stable_secret.initialized)
3203 		secret = idev->cnf.stable_secret.secret;
3204 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3205 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3206 	else
3207 		return -1;
3208 
3209 retry:
3210 	spin_lock_bh(&lock);
3211 
3212 	sha_init(digest);
3213 	memset(&data, 0, sizeof(data));
3214 	memset(workspace, 0, sizeof(workspace));
3215 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3216 	data.prefix[0] = address->s6_addr32[0];
3217 	data.prefix[1] = address->s6_addr32[1];
3218 	data.secret = secret;
3219 	data.dad_count = dad_count;
3220 
3221 	sha_transform(digest, data.__data, workspace);
3222 
3223 	temp = *address;
3224 	temp.s6_addr32[2] = (__force __be32)digest[0];
3225 	temp.s6_addr32[3] = (__force __be32)digest[1];
3226 
3227 	spin_unlock_bh(&lock);
3228 
3229 	if (ipv6_reserved_interfaceid(temp)) {
3230 		dad_count++;
3231 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3232 			return -1;
3233 		goto retry;
3234 	}
3235 
3236 	*address = temp;
3237 	return 0;
3238 }
3239 
3240 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3241 {
3242 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3243 
3244 	if (s->initialized)
3245 		return;
3246 	s = &idev->cnf.stable_secret;
3247 	get_random_bytes(&s->secret, sizeof(s->secret));
3248 	s->initialized = true;
3249 }
3250 
3251 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3252 {
3253 	struct in6_addr addr;
3254 
3255 	/* no link local addresses on L3 master devices */
3256 	if (netif_is_l3_master(idev->dev))
3257 		return;
3258 
3259 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3260 
3261 	switch (idev->cnf.addr_gen_mode) {
3262 	case IN6_ADDR_GEN_MODE_RANDOM:
3263 		ipv6_gen_mode_random_init(idev);
3264 		/* fallthrough */
3265 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3266 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3267 			addrconf_add_linklocal(idev, &addr,
3268 					       IFA_F_STABLE_PRIVACY);
3269 		else if (prefix_route)
3270 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3271 					      0, 0, GFP_KERNEL);
3272 		break;
3273 	case IN6_ADDR_GEN_MODE_EUI64:
3274 		/* addrconf_add_linklocal also adds a prefix_route and we
3275 		 * only need to care about prefix routes if ipv6_generate_eui64
3276 		 * couldn't generate one.
3277 		 */
3278 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3279 			addrconf_add_linklocal(idev, &addr, 0);
3280 		else if (prefix_route)
3281 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3282 					      0, 0, GFP_KERNEL);
3283 		break;
3284 	case IN6_ADDR_GEN_MODE_NONE:
3285 	default:
3286 		/* will not add any link local address */
3287 		break;
3288 	}
3289 }
3290 
3291 static void addrconf_dev_config(struct net_device *dev)
3292 {
3293 	struct inet6_dev *idev;
3294 
3295 	ASSERT_RTNL();
3296 
3297 	if ((dev->type != ARPHRD_ETHER) &&
3298 	    (dev->type != ARPHRD_FDDI) &&
3299 	    (dev->type != ARPHRD_ARCNET) &&
3300 	    (dev->type != ARPHRD_INFINIBAND) &&
3301 	    (dev->type != ARPHRD_IEEE1394) &&
3302 	    (dev->type != ARPHRD_TUNNEL6) &&
3303 	    (dev->type != ARPHRD_6LOWPAN) &&
3304 	    (dev->type != ARPHRD_IP6GRE) &&
3305 	    (dev->type != ARPHRD_IPGRE) &&
3306 	    (dev->type != ARPHRD_TUNNEL) &&
3307 	    (dev->type != ARPHRD_NONE) &&
3308 	    (dev->type != ARPHRD_RAWIP)) {
3309 		/* Alas, we support only Ethernet autoconfiguration. */
3310 		return;
3311 	}
3312 
3313 	idev = addrconf_add_dev(dev);
3314 	if (IS_ERR(idev))
3315 		return;
3316 
3317 	/* this device type has no EUI support */
3318 	if (dev->type == ARPHRD_NONE &&
3319 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3320 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3321 
3322 	addrconf_addr_gen(idev, false);
3323 }
3324 
3325 #if IS_ENABLED(CONFIG_IPV6_SIT)
3326 static void addrconf_sit_config(struct net_device *dev)
3327 {
3328 	struct inet6_dev *idev;
3329 
3330 	ASSERT_RTNL();
3331 
3332 	/*
3333 	 * Configure the tunnel with one of our IPv4
3334 	 * addresses... we should configure all of
3335 	 * our v4 addrs in the tunnel
3336 	 */
3337 
3338 	idev = ipv6_find_idev(dev);
3339 	if (!idev) {
3340 		pr_debug("%s: add_dev failed\n", __func__);
3341 		return;
3342 	}
3343 
3344 	if (dev->priv_flags & IFF_ISATAP) {
3345 		addrconf_addr_gen(idev, false);
3346 		return;
3347 	}
3348 
3349 	sit_add_v4_addrs(idev);
3350 
3351 	if (dev->flags&IFF_POINTOPOINT)
3352 		addrconf_add_mroute(dev);
3353 }
3354 #endif
3355 
3356 #if IS_ENABLED(CONFIG_NET_IPGRE)
3357 static void addrconf_gre_config(struct net_device *dev)
3358 {
3359 	struct inet6_dev *idev;
3360 
3361 	ASSERT_RTNL();
3362 
3363 	idev = ipv6_find_idev(dev);
3364 	if (!idev) {
3365 		pr_debug("%s: add_dev failed\n", __func__);
3366 		return;
3367 	}
3368 
3369 	addrconf_addr_gen(idev, true);
3370 	if (dev->flags & IFF_POINTOPOINT)
3371 		addrconf_add_mroute(dev);
3372 }
3373 #endif
3374 
3375 static int fixup_permanent_addr(struct net *net,
3376 				struct inet6_dev *idev,
3377 				struct inet6_ifaddr *ifp)
3378 {
3379 	/* !fib6_node means the host route was removed from the
3380 	 * FIB, for example, if 'lo' device is taken down. In that
3381 	 * case regenerate the host route.
3382 	 */
3383 	if (!ifp->rt || !ifp->rt->fib6_node) {
3384 		struct fib6_info *f6i, *prev;
3385 
3386 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3387 					 GFP_ATOMIC);
3388 		if (IS_ERR(f6i))
3389 			return PTR_ERR(f6i);
3390 
3391 		/* ifp->rt can be accessed outside of rtnl */
3392 		spin_lock(&ifp->lock);
3393 		prev = ifp->rt;
3394 		ifp->rt = f6i;
3395 		spin_unlock(&ifp->lock);
3396 
3397 		fib6_info_release(prev);
3398 	}
3399 
3400 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3401 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3402 				      ifp->rt_priority, idev->dev, 0, 0,
3403 				      GFP_ATOMIC);
3404 	}
3405 
3406 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3407 		addrconf_dad_start(ifp);
3408 
3409 	return 0;
3410 }
3411 
3412 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3413 {
3414 	struct inet6_ifaddr *ifp, *tmp;
3415 	struct inet6_dev *idev;
3416 
3417 	idev = __in6_dev_get(dev);
3418 	if (!idev)
3419 		return;
3420 
3421 	write_lock_bh(&idev->lock);
3422 
3423 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3424 		if ((ifp->flags & IFA_F_PERMANENT) &&
3425 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3426 			write_unlock_bh(&idev->lock);
3427 			in6_ifa_hold(ifp);
3428 			ipv6_del_addr(ifp);
3429 			write_lock_bh(&idev->lock);
3430 
3431 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3432 					     idev->dev->name, &ifp->addr);
3433 		}
3434 	}
3435 
3436 	write_unlock_bh(&idev->lock);
3437 }
3438 
3439 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3440 			   void *ptr)
3441 {
3442 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3443 	struct netdev_notifier_change_info *change_info;
3444 	struct netdev_notifier_changeupper_info *info;
3445 	struct inet6_dev *idev = __in6_dev_get(dev);
3446 	struct net *net = dev_net(dev);
3447 	int run_pending = 0;
3448 	int err;
3449 
3450 	switch (event) {
3451 	case NETDEV_REGISTER:
3452 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3453 			idev = ipv6_add_dev(dev);
3454 			if (IS_ERR(idev))
3455 				return notifier_from_errno(PTR_ERR(idev));
3456 		}
3457 		break;
3458 
3459 	case NETDEV_CHANGEMTU:
3460 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3461 		if (dev->mtu < IPV6_MIN_MTU) {
3462 			addrconf_ifdown(dev, dev != net->loopback_dev);
3463 			break;
3464 		}
3465 
3466 		if (idev) {
3467 			rt6_mtu_change(dev, dev->mtu);
3468 			idev->cnf.mtu6 = dev->mtu;
3469 			break;
3470 		}
3471 
3472 		/* allocate new idev */
3473 		idev = ipv6_add_dev(dev);
3474 		if (IS_ERR(idev))
3475 			break;
3476 
3477 		/* device is still not ready */
3478 		if (!(idev->if_flags & IF_READY))
3479 			break;
3480 
3481 		run_pending = 1;
3482 
3483 		/* fall through */
3484 
3485 	case NETDEV_UP:
3486 	case NETDEV_CHANGE:
3487 		if (dev->flags & IFF_SLAVE)
3488 			break;
3489 
3490 		if (idev && idev->cnf.disable_ipv6)
3491 			break;
3492 
3493 		if (event == NETDEV_UP) {
3494 			/* restore routes for permanent addresses */
3495 			addrconf_permanent_addr(net, dev);
3496 
3497 			if (!addrconf_link_ready(dev)) {
3498 				/* device is not ready yet. */
3499 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3500 					 dev->name);
3501 				break;
3502 			}
3503 
3504 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3505 				idev = ipv6_add_dev(dev);
3506 
3507 			if (!IS_ERR_OR_NULL(idev)) {
3508 				idev->if_flags |= IF_READY;
3509 				run_pending = 1;
3510 			}
3511 		} else if (event == NETDEV_CHANGE) {
3512 			if (!addrconf_link_ready(dev)) {
3513 				/* device is still not ready. */
3514 				rt6_sync_down_dev(dev, event);
3515 				break;
3516 			}
3517 
3518 			if (!IS_ERR_OR_NULL(idev)) {
3519 				if (idev->if_flags & IF_READY) {
3520 					/* device is already configured -
3521 					 * but resend MLD reports, we might
3522 					 * have roamed and need to update
3523 					 * multicast snooping switches
3524 					 */
3525 					ipv6_mc_up(idev);
3526 					change_info = ptr;
3527 					if (change_info->flags_changed & IFF_NOARP)
3528 						addrconf_dad_run(idev, true);
3529 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3530 					break;
3531 				}
3532 				idev->if_flags |= IF_READY;
3533 			}
3534 
3535 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3536 				dev->name);
3537 
3538 			run_pending = 1;
3539 		}
3540 
3541 		switch (dev->type) {
3542 #if IS_ENABLED(CONFIG_IPV6_SIT)
3543 		case ARPHRD_SIT:
3544 			addrconf_sit_config(dev);
3545 			break;
3546 #endif
3547 #if IS_ENABLED(CONFIG_NET_IPGRE)
3548 		case ARPHRD_IPGRE:
3549 			addrconf_gre_config(dev);
3550 			break;
3551 #endif
3552 		case ARPHRD_LOOPBACK:
3553 			init_loopback(dev);
3554 			break;
3555 
3556 		default:
3557 			addrconf_dev_config(dev);
3558 			break;
3559 		}
3560 
3561 		if (!IS_ERR_OR_NULL(idev)) {
3562 			if (run_pending)
3563 				addrconf_dad_run(idev, false);
3564 
3565 			/* Device has an address by now */
3566 			rt6_sync_up(dev, RTNH_F_DEAD);
3567 
3568 			/*
3569 			 * If the MTU changed during the interface down,
3570 			 * when the interface up, the changed MTU must be
3571 			 * reflected in the idev as well as routers.
3572 			 */
3573 			if (idev->cnf.mtu6 != dev->mtu &&
3574 			    dev->mtu >= IPV6_MIN_MTU) {
3575 				rt6_mtu_change(dev, dev->mtu);
3576 				idev->cnf.mtu6 = dev->mtu;
3577 			}
3578 			idev->tstamp = jiffies;
3579 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3580 
3581 			/*
3582 			 * If the changed mtu during down is lower than
3583 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3584 			 */
3585 			if (dev->mtu < IPV6_MIN_MTU)
3586 				addrconf_ifdown(dev, dev != net->loopback_dev);
3587 		}
3588 		break;
3589 
3590 	case NETDEV_DOWN:
3591 	case NETDEV_UNREGISTER:
3592 		/*
3593 		 *	Remove all addresses from this interface.
3594 		 */
3595 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3596 		break;
3597 
3598 	case NETDEV_CHANGENAME:
3599 		if (idev) {
3600 			snmp6_unregister_dev(idev);
3601 			addrconf_sysctl_unregister(idev);
3602 			err = addrconf_sysctl_register(idev);
3603 			if (err)
3604 				return notifier_from_errno(err);
3605 			err = snmp6_register_dev(idev);
3606 			if (err) {
3607 				addrconf_sysctl_unregister(idev);
3608 				return notifier_from_errno(err);
3609 			}
3610 		}
3611 		break;
3612 
3613 	case NETDEV_PRE_TYPE_CHANGE:
3614 	case NETDEV_POST_TYPE_CHANGE:
3615 		if (idev)
3616 			addrconf_type_change(dev, event);
3617 		break;
3618 
3619 	case NETDEV_CHANGEUPPER:
3620 		info = ptr;
3621 
3622 		/* flush all routes if dev is linked to or unlinked from
3623 		 * an L3 master device (e.g., VRF)
3624 		 */
3625 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3626 			addrconf_ifdown(dev, 0);
3627 	}
3628 
3629 	return NOTIFY_OK;
3630 }
3631 
3632 /*
3633  *	addrconf module should be notified of a device going up
3634  */
3635 static struct notifier_block ipv6_dev_notf = {
3636 	.notifier_call = addrconf_notify,
3637 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3638 };
3639 
3640 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3641 {
3642 	struct inet6_dev *idev;
3643 	ASSERT_RTNL();
3644 
3645 	idev = __in6_dev_get(dev);
3646 
3647 	if (event == NETDEV_POST_TYPE_CHANGE)
3648 		ipv6_mc_remap(idev);
3649 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3650 		ipv6_mc_unmap(idev);
3651 }
3652 
3653 static bool addr_is_local(const struct in6_addr *addr)
3654 {
3655 	return ipv6_addr_type(addr) &
3656 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3657 }
3658 
3659 static int addrconf_ifdown(struct net_device *dev, int how)
3660 {
3661 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3662 	struct net *net = dev_net(dev);
3663 	struct inet6_dev *idev;
3664 	struct inet6_ifaddr *ifa, *tmp;
3665 	bool keep_addr = false;
3666 	int state, i;
3667 
3668 	ASSERT_RTNL();
3669 
3670 	rt6_disable_ip(dev, event);
3671 
3672 	idev = __in6_dev_get(dev);
3673 	if (!idev)
3674 		return -ENODEV;
3675 
3676 	/*
3677 	 * Step 1: remove reference to ipv6 device from parent device.
3678 	 *	   Do not dev_put!
3679 	 */
3680 	if (how) {
3681 		idev->dead = 1;
3682 
3683 		/* protected by rtnl_lock */
3684 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3685 
3686 		/* Step 1.5: remove snmp6 entry */
3687 		snmp6_unregister_dev(idev);
3688 
3689 	}
3690 
3691 	/* combine the user config with event to determine if permanent
3692 	 * addresses are to be removed from address hash table
3693 	 */
3694 	if (!how && !idev->cnf.disable_ipv6) {
3695 		/* aggregate the system setting and interface setting */
3696 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3697 
3698 		if (!_keep_addr)
3699 			_keep_addr = idev->cnf.keep_addr_on_down;
3700 
3701 		keep_addr = (_keep_addr > 0);
3702 	}
3703 
3704 	/* Step 2: clear hash table */
3705 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3706 		struct hlist_head *h = &inet6_addr_lst[i];
3707 
3708 		spin_lock_bh(&addrconf_hash_lock);
3709 restart:
3710 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3711 			if (ifa->idev == idev) {
3712 				addrconf_del_dad_work(ifa);
3713 				/* combined flag + permanent flag decide if
3714 				 * address is retained on a down event
3715 				 */
3716 				if (!keep_addr ||
3717 				    !(ifa->flags & IFA_F_PERMANENT) ||
3718 				    addr_is_local(&ifa->addr)) {
3719 					hlist_del_init_rcu(&ifa->addr_lst);
3720 					goto restart;
3721 				}
3722 			}
3723 		}
3724 		spin_unlock_bh(&addrconf_hash_lock);
3725 	}
3726 
3727 	write_lock_bh(&idev->lock);
3728 
3729 	addrconf_del_rs_timer(idev);
3730 
3731 	/* Step 2: clear flags for stateless addrconf */
3732 	if (!how)
3733 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3734 
3735 	/* Step 3: clear tempaddr list */
3736 	while (!list_empty(&idev->tempaddr_list)) {
3737 		ifa = list_first_entry(&idev->tempaddr_list,
3738 				       struct inet6_ifaddr, tmp_list);
3739 		list_del(&ifa->tmp_list);
3740 		write_unlock_bh(&idev->lock);
3741 		spin_lock_bh(&ifa->lock);
3742 
3743 		if (ifa->ifpub) {
3744 			in6_ifa_put(ifa->ifpub);
3745 			ifa->ifpub = NULL;
3746 		}
3747 		spin_unlock_bh(&ifa->lock);
3748 		in6_ifa_put(ifa);
3749 		write_lock_bh(&idev->lock);
3750 	}
3751 
3752 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3753 		struct fib6_info *rt = NULL;
3754 		bool keep;
3755 
3756 		addrconf_del_dad_work(ifa);
3757 
3758 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3759 			!addr_is_local(&ifa->addr);
3760 
3761 		write_unlock_bh(&idev->lock);
3762 		spin_lock_bh(&ifa->lock);
3763 
3764 		if (keep) {
3765 			/* set state to skip the notifier below */
3766 			state = INET6_IFADDR_STATE_DEAD;
3767 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3768 			if (!(ifa->flags & IFA_F_NODAD))
3769 				ifa->flags |= IFA_F_TENTATIVE;
3770 
3771 			rt = ifa->rt;
3772 			ifa->rt = NULL;
3773 		} else {
3774 			state = ifa->state;
3775 			ifa->state = INET6_IFADDR_STATE_DEAD;
3776 		}
3777 
3778 		spin_unlock_bh(&ifa->lock);
3779 
3780 		if (rt)
3781 			ip6_del_rt(net, rt);
3782 
3783 		if (state != INET6_IFADDR_STATE_DEAD) {
3784 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3785 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3786 		} else {
3787 			if (idev->cnf.forwarding)
3788 				addrconf_leave_anycast(ifa);
3789 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3790 		}
3791 
3792 		write_lock_bh(&idev->lock);
3793 		if (!keep) {
3794 			list_del_rcu(&ifa->if_list);
3795 			in6_ifa_put(ifa);
3796 		}
3797 	}
3798 
3799 	write_unlock_bh(&idev->lock);
3800 
3801 	/* Step 5: Discard anycast and multicast list */
3802 	if (how) {
3803 		ipv6_ac_destroy_dev(idev);
3804 		ipv6_mc_destroy_dev(idev);
3805 	} else {
3806 		ipv6_mc_down(idev);
3807 	}
3808 
3809 	idev->tstamp = jiffies;
3810 
3811 	/* Last: Shot the device (if unregistered) */
3812 	if (how) {
3813 		addrconf_sysctl_unregister(idev);
3814 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3815 		neigh_ifdown(&nd_tbl, dev);
3816 		in6_dev_put(idev);
3817 	}
3818 	return 0;
3819 }
3820 
3821 static void addrconf_rs_timer(struct timer_list *t)
3822 {
3823 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3824 	struct net_device *dev = idev->dev;
3825 	struct in6_addr lladdr;
3826 
3827 	write_lock(&idev->lock);
3828 	if (idev->dead || !(idev->if_flags & IF_READY))
3829 		goto out;
3830 
3831 	if (!ipv6_accept_ra(idev))
3832 		goto out;
3833 
3834 	/* Announcement received after solicitation was sent */
3835 	if (idev->if_flags & IF_RA_RCVD)
3836 		goto out;
3837 
3838 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3839 		write_unlock(&idev->lock);
3840 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3841 			ndisc_send_rs(dev, &lladdr,
3842 				      &in6addr_linklocal_allrouters);
3843 		else
3844 			goto put;
3845 
3846 		write_lock(&idev->lock);
3847 		idev->rs_interval = rfc3315_s14_backoff_update(
3848 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3849 		/* The wait after the last probe can be shorter */
3850 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3851 					     idev->cnf.rtr_solicits) ?
3852 				      idev->cnf.rtr_solicit_delay :
3853 				      idev->rs_interval);
3854 	} else {
3855 		/*
3856 		 * Note: we do not support deprecated "all on-link"
3857 		 * assumption any longer.
3858 		 */
3859 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3860 	}
3861 
3862 out:
3863 	write_unlock(&idev->lock);
3864 put:
3865 	in6_dev_put(idev);
3866 }
3867 
3868 /*
3869  *	Duplicate Address Detection
3870  */
3871 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3872 {
3873 	unsigned long rand_num;
3874 	struct inet6_dev *idev = ifp->idev;
3875 	u64 nonce;
3876 
3877 	if (ifp->flags & IFA_F_OPTIMISTIC)
3878 		rand_num = 0;
3879 	else
3880 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3881 
3882 	nonce = 0;
3883 	if (idev->cnf.enhanced_dad ||
3884 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3885 		do
3886 			get_random_bytes(&nonce, 6);
3887 		while (nonce == 0);
3888 	}
3889 	ifp->dad_nonce = nonce;
3890 	ifp->dad_probes = idev->cnf.dad_transmits;
3891 	addrconf_mod_dad_work(ifp, rand_num);
3892 }
3893 
3894 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3895 {
3896 	struct inet6_dev *idev = ifp->idev;
3897 	struct net_device *dev = idev->dev;
3898 	bool bump_id, notify = false;
3899 	struct net *net;
3900 
3901 	addrconf_join_solict(dev, &ifp->addr);
3902 
3903 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3904 
3905 	read_lock_bh(&idev->lock);
3906 	spin_lock(&ifp->lock);
3907 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3908 		goto out;
3909 
3910 	net = dev_net(dev);
3911 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3912 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3913 	     idev->cnf.accept_dad < 1) ||
3914 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3915 	    ifp->flags & IFA_F_NODAD) {
3916 		bool send_na = false;
3917 
3918 		if (ifp->flags & IFA_F_TENTATIVE &&
3919 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3920 			send_na = true;
3921 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3922 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3923 		spin_unlock(&ifp->lock);
3924 		read_unlock_bh(&idev->lock);
3925 
3926 		addrconf_dad_completed(ifp, bump_id, send_na);
3927 		return;
3928 	}
3929 
3930 	if (!(idev->if_flags & IF_READY)) {
3931 		spin_unlock(&ifp->lock);
3932 		read_unlock_bh(&idev->lock);
3933 		/*
3934 		 * If the device is not ready:
3935 		 * - keep it tentative if it is a permanent address.
3936 		 * - otherwise, kill it.
3937 		 */
3938 		in6_ifa_hold(ifp);
3939 		addrconf_dad_stop(ifp, 0);
3940 		return;
3941 	}
3942 
3943 	/*
3944 	 * Optimistic nodes can start receiving
3945 	 * Frames right away
3946 	 */
3947 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3948 		ip6_ins_rt(net, ifp->rt);
3949 		if (ipv6_use_optimistic_addr(net, idev)) {
3950 			/* Because optimistic nodes can use this address,
3951 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3952 			 */
3953 			notify = true;
3954 		}
3955 	}
3956 
3957 	addrconf_dad_kick(ifp);
3958 out:
3959 	spin_unlock(&ifp->lock);
3960 	read_unlock_bh(&idev->lock);
3961 	if (notify)
3962 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3963 }
3964 
3965 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3966 {
3967 	bool begin_dad = false;
3968 
3969 	spin_lock_bh(&ifp->lock);
3970 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3971 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3972 		begin_dad = true;
3973 	}
3974 	spin_unlock_bh(&ifp->lock);
3975 
3976 	if (begin_dad)
3977 		addrconf_mod_dad_work(ifp, 0);
3978 }
3979 
3980 static void addrconf_dad_work(struct work_struct *w)
3981 {
3982 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3983 						struct inet6_ifaddr,
3984 						dad_work);
3985 	struct inet6_dev *idev = ifp->idev;
3986 	bool bump_id, disable_ipv6 = false;
3987 	struct in6_addr mcaddr;
3988 
3989 	enum {
3990 		DAD_PROCESS,
3991 		DAD_BEGIN,
3992 		DAD_ABORT,
3993 	} action = DAD_PROCESS;
3994 
3995 	rtnl_lock();
3996 
3997 	spin_lock_bh(&ifp->lock);
3998 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3999 		action = DAD_BEGIN;
4000 		ifp->state = INET6_IFADDR_STATE_DAD;
4001 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4002 		action = DAD_ABORT;
4003 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4004 
4005 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4006 		     idev->cnf.accept_dad > 1) &&
4007 		    !idev->cnf.disable_ipv6 &&
4008 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4009 			struct in6_addr addr;
4010 
4011 			addr.s6_addr32[0] = htonl(0xfe800000);
4012 			addr.s6_addr32[1] = 0;
4013 
4014 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4015 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4016 				/* DAD failed for link-local based on MAC */
4017 				idev->cnf.disable_ipv6 = 1;
4018 
4019 				pr_info("%s: IPv6 being disabled!\n",
4020 					ifp->idev->dev->name);
4021 				disable_ipv6 = true;
4022 			}
4023 		}
4024 	}
4025 	spin_unlock_bh(&ifp->lock);
4026 
4027 	if (action == DAD_BEGIN) {
4028 		addrconf_dad_begin(ifp);
4029 		goto out;
4030 	} else if (action == DAD_ABORT) {
4031 		in6_ifa_hold(ifp);
4032 		addrconf_dad_stop(ifp, 1);
4033 		if (disable_ipv6)
4034 			addrconf_ifdown(idev->dev, 0);
4035 		goto out;
4036 	}
4037 
4038 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4039 		goto out;
4040 
4041 	write_lock_bh(&idev->lock);
4042 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4043 		write_unlock_bh(&idev->lock);
4044 		goto out;
4045 	}
4046 
4047 	spin_lock(&ifp->lock);
4048 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4049 		spin_unlock(&ifp->lock);
4050 		write_unlock_bh(&idev->lock);
4051 		goto out;
4052 	}
4053 
4054 	if (ifp->dad_probes == 0) {
4055 		bool send_na = false;
4056 
4057 		/*
4058 		 * DAD was successful
4059 		 */
4060 
4061 		if (ifp->flags & IFA_F_TENTATIVE &&
4062 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4063 			send_na = true;
4064 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4065 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4066 		spin_unlock(&ifp->lock);
4067 		write_unlock_bh(&idev->lock);
4068 
4069 		addrconf_dad_completed(ifp, bump_id, send_na);
4070 
4071 		goto out;
4072 	}
4073 
4074 	ifp->dad_probes--;
4075 	addrconf_mod_dad_work(ifp,
4076 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4077 	spin_unlock(&ifp->lock);
4078 	write_unlock_bh(&idev->lock);
4079 
4080 	/* send a neighbour solicitation for our addr */
4081 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4082 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4083 		      ifp->dad_nonce);
4084 out:
4085 	in6_ifa_put(ifp);
4086 	rtnl_unlock();
4087 }
4088 
4089 /* ifp->idev must be at least read locked */
4090 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4091 {
4092 	struct inet6_ifaddr *ifpiter;
4093 	struct inet6_dev *idev = ifp->idev;
4094 
4095 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4096 		if (ifpiter->scope > IFA_LINK)
4097 			break;
4098 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4099 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4100 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4101 		    IFA_F_PERMANENT)
4102 			return false;
4103 	}
4104 	return true;
4105 }
4106 
4107 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4108 				   bool send_na)
4109 {
4110 	struct net_device *dev = ifp->idev->dev;
4111 	struct in6_addr lladdr;
4112 	bool send_rs, send_mld;
4113 
4114 	addrconf_del_dad_work(ifp);
4115 
4116 	/*
4117 	 *	Configure the address for reception. Now it is valid.
4118 	 */
4119 
4120 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4121 
4122 	/* If added prefix is link local and we are prepared to process
4123 	   router advertisements, start sending router solicitations.
4124 	 */
4125 
4126 	read_lock_bh(&ifp->idev->lock);
4127 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4128 	send_rs = send_mld &&
4129 		  ipv6_accept_ra(ifp->idev) &&
4130 		  ifp->idev->cnf.rtr_solicits != 0 &&
4131 		  (dev->flags&IFF_LOOPBACK) == 0;
4132 	read_unlock_bh(&ifp->idev->lock);
4133 
4134 	/* While dad is in progress mld report's source address is in6_addrany.
4135 	 * Resend with proper ll now.
4136 	 */
4137 	if (send_mld)
4138 		ipv6_mc_dad_complete(ifp->idev);
4139 
4140 	/* send unsolicited NA if enabled */
4141 	if (send_na &&
4142 	    (ifp->idev->cnf.ndisc_notify ||
4143 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4144 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4145 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4146 			      /*solicited=*/ false, /*override=*/ true,
4147 			      /*inc_opt=*/ true);
4148 	}
4149 
4150 	if (send_rs) {
4151 		/*
4152 		 *	If a host as already performed a random delay
4153 		 *	[...] as part of DAD [...] there is no need
4154 		 *	to delay again before sending the first RS
4155 		 */
4156 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4157 			return;
4158 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4159 
4160 		write_lock_bh(&ifp->idev->lock);
4161 		spin_lock(&ifp->lock);
4162 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4163 			ifp->idev->cnf.rtr_solicit_interval);
4164 		ifp->idev->rs_probes = 1;
4165 		ifp->idev->if_flags |= IF_RS_SENT;
4166 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4167 		spin_unlock(&ifp->lock);
4168 		write_unlock_bh(&ifp->idev->lock);
4169 	}
4170 
4171 	if (bump_id)
4172 		rt_genid_bump_ipv6(dev_net(dev));
4173 
4174 	/* Make sure that a new temporary address will be created
4175 	 * before this temporary address becomes deprecated.
4176 	 */
4177 	if (ifp->flags & IFA_F_TEMPORARY)
4178 		addrconf_verify_rtnl();
4179 }
4180 
4181 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4182 {
4183 	struct inet6_ifaddr *ifp;
4184 
4185 	read_lock_bh(&idev->lock);
4186 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4187 		spin_lock(&ifp->lock);
4188 		if ((ifp->flags & IFA_F_TENTATIVE &&
4189 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4190 			if (restart)
4191 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4192 			addrconf_dad_kick(ifp);
4193 		}
4194 		spin_unlock(&ifp->lock);
4195 	}
4196 	read_unlock_bh(&idev->lock);
4197 }
4198 
4199 #ifdef CONFIG_PROC_FS
4200 struct if6_iter_state {
4201 	struct seq_net_private p;
4202 	int bucket;
4203 	int offset;
4204 };
4205 
4206 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4207 {
4208 	struct if6_iter_state *state = seq->private;
4209 	struct net *net = seq_file_net(seq);
4210 	struct inet6_ifaddr *ifa = NULL;
4211 	int p = 0;
4212 
4213 	/* initial bucket if pos is 0 */
4214 	if (pos == 0) {
4215 		state->bucket = 0;
4216 		state->offset = 0;
4217 	}
4218 
4219 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4220 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4221 					 addr_lst) {
4222 			if (!net_eq(dev_net(ifa->idev->dev), net))
4223 				continue;
4224 			/* sync with offset */
4225 			if (p < state->offset) {
4226 				p++;
4227 				continue;
4228 			}
4229 			return ifa;
4230 		}
4231 
4232 		/* prepare for next bucket */
4233 		state->offset = 0;
4234 		p = 0;
4235 	}
4236 	return NULL;
4237 }
4238 
4239 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4240 					 struct inet6_ifaddr *ifa)
4241 {
4242 	struct if6_iter_state *state = seq->private;
4243 	struct net *net = seq_file_net(seq);
4244 
4245 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4246 		if (!net_eq(dev_net(ifa->idev->dev), net))
4247 			continue;
4248 		state->offset++;
4249 		return ifa;
4250 	}
4251 
4252 	state->offset = 0;
4253 	while (++state->bucket < IN6_ADDR_HSIZE) {
4254 		hlist_for_each_entry_rcu(ifa,
4255 				     &inet6_addr_lst[state->bucket], addr_lst) {
4256 			if (!net_eq(dev_net(ifa->idev->dev), net))
4257 				continue;
4258 			return ifa;
4259 		}
4260 	}
4261 
4262 	return NULL;
4263 }
4264 
4265 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4266 	__acquires(rcu)
4267 {
4268 	rcu_read_lock();
4269 	return if6_get_first(seq, *pos);
4270 }
4271 
4272 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4273 {
4274 	struct inet6_ifaddr *ifa;
4275 
4276 	ifa = if6_get_next(seq, v);
4277 	++*pos;
4278 	return ifa;
4279 }
4280 
4281 static void if6_seq_stop(struct seq_file *seq, void *v)
4282 	__releases(rcu)
4283 {
4284 	rcu_read_unlock();
4285 }
4286 
4287 static int if6_seq_show(struct seq_file *seq, void *v)
4288 {
4289 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4290 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4291 		   &ifp->addr,
4292 		   ifp->idev->dev->ifindex,
4293 		   ifp->prefix_len,
4294 		   ifp->scope,
4295 		   (u8) ifp->flags,
4296 		   ifp->idev->dev->name);
4297 	return 0;
4298 }
4299 
4300 static const struct seq_operations if6_seq_ops = {
4301 	.start	= if6_seq_start,
4302 	.next	= if6_seq_next,
4303 	.show	= if6_seq_show,
4304 	.stop	= if6_seq_stop,
4305 };
4306 
4307 static int __net_init if6_proc_net_init(struct net *net)
4308 {
4309 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4310 			sizeof(struct if6_iter_state)))
4311 		return -ENOMEM;
4312 	return 0;
4313 }
4314 
4315 static void __net_exit if6_proc_net_exit(struct net *net)
4316 {
4317 	remove_proc_entry("if_inet6", net->proc_net);
4318 }
4319 
4320 static struct pernet_operations if6_proc_net_ops = {
4321 	.init = if6_proc_net_init,
4322 	.exit = if6_proc_net_exit,
4323 };
4324 
4325 int __init if6_proc_init(void)
4326 {
4327 	return register_pernet_subsys(&if6_proc_net_ops);
4328 }
4329 
4330 void if6_proc_exit(void)
4331 {
4332 	unregister_pernet_subsys(&if6_proc_net_ops);
4333 }
4334 #endif	/* CONFIG_PROC_FS */
4335 
4336 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4337 /* Check if address is a home address configured on any interface. */
4338 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4339 {
4340 	unsigned int hash = inet6_addr_hash(net, addr);
4341 	struct inet6_ifaddr *ifp = NULL;
4342 	int ret = 0;
4343 
4344 	rcu_read_lock();
4345 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4346 		if (!net_eq(dev_net(ifp->idev->dev), net))
4347 			continue;
4348 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4349 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4350 			ret = 1;
4351 			break;
4352 		}
4353 	}
4354 	rcu_read_unlock();
4355 	return ret;
4356 }
4357 #endif
4358 
4359 /*
4360  *	Periodic address status verification
4361  */
4362 
4363 static void addrconf_verify_rtnl(void)
4364 {
4365 	unsigned long now, next, next_sec, next_sched;
4366 	struct inet6_ifaddr *ifp;
4367 	int i;
4368 
4369 	ASSERT_RTNL();
4370 
4371 	rcu_read_lock_bh();
4372 	now = jiffies;
4373 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4374 
4375 	cancel_delayed_work(&addr_chk_work);
4376 
4377 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4378 restart:
4379 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4380 			unsigned long age;
4381 
4382 			/* When setting preferred_lft to a value not zero or
4383 			 * infinity, while valid_lft is infinity
4384 			 * IFA_F_PERMANENT has a non-infinity life time.
4385 			 */
4386 			if ((ifp->flags & IFA_F_PERMANENT) &&
4387 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4388 				continue;
4389 
4390 			spin_lock(&ifp->lock);
4391 			/* We try to batch several events at once. */
4392 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4393 
4394 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4395 			    age >= ifp->valid_lft) {
4396 				spin_unlock(&ifp->lock);
4397 				in6_ifa_hold(ifp);
4398 				ipv6_del_addr(ifp);
4399 				goto restart;
4400 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4401 				spin_unlock(&ifp->lock);
4402 				continue;
4403 			} else if (age >= ifp->prefered_lft) {
4404 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4405 				int deprecate = 0;
4406 
4407 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4408 					deprecate = 1;
4409 					ifp->flags |= IFA_F_DEPRECATED;
4410 				}
4411 
4412 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4413 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4414 					next = ifp->tstamp + ifp->valid_lft * HZ;
4415 
4416 				spin_unlock(&ifp->lock);
4417 
4418 				if (deprecate) {
4419 					in6_ifa_hold(ifp);
4420 
4421 					ipv6_ifa_notify(0, ifp);
4422 					in6_ifa_put(ifp);
4423 					goto restart;
4424 				}
4425 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4426 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4427 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4428 					ifp->idev->cnf.dad_transmits *
4429 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4430 
4431 				if (age >= ifp->prefered_lft - regen_advance) {
4432 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4433 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4434 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4435 					if (!ifp->regen_count && ifpub) {
4436 						ifp->regen_count++;
4437 						in6_ifa_hold(ifp);
4438 						in6_ifa_hold(ifpub);
4439 						spin_unlock(&ifp->lock);
4440 
4441 						spin_lock(&ifpub->lock);
4442 						ifpub->regen_count = 0;
4443 						spin_unlock(&ifpub->lock);
4444 						rcu_read_unlock_bh();
4445 						ipv6_create_tempaddr(ifpub, ifp, true);
4446 						in6_ifa_put(ifpub);
4447 						in6_ifa_put(ifp);
4448 						rcu_read_lock_bh();
4449 						goto restart;
4450 					}
4451 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4452 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4453 				spin_unlock(&ifp->lock);
4454 			} else {
4455 				/* ifp->prefered_lft <= ifp->valid_lft */
4456 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4457 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4458 				spin_unlock(&ifp->lock);
4459 			}
4460 		}
4461 	}
4462 
4463 	next_sec = round_jiffies_up(next);
4464 	next_sched = next;
4465 
4466 	/* If rounded timeout is accurate enough, accept it. */
4467 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4468 		next_sched = next_sec;
4469 
4470 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4471 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4472 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4473 
4474 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4475 		 now, next, next_sec, next_sched);
4476 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4477 	rcu_read_unlock_bh();
4478 }
4479 
4480 static void addrconf_verify_work(struct work_struct *w)
4481 {
4482 	rtnl_lock();
4483 	addrconf_verify_rtnl();
4484 	rtnl_unlock();
4485 }
4486 
4487 static void addrconf_verify(void)
4488 {
4489 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4490 }
4491 
4492 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4493 				     struct in6_addr **peer_pfx)
4494 {
4495 	struct in6_addr *pfx = NULL;
4496 
4497 	*peer_pfx = NULL;
4498 
4499 	if (addr)
4500 		pfx = nla_data(addr);
4501 
4502 	if (local) {
4503 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4504 			*peer_pfx = pfx;
4505 		pfx = nla_data(local);
4506 	}
4507 
4508 	return pfx;
4509 }
4510 
4511 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4512 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4513 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4514 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4515 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4516 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4517 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4518 };
4519 
4520 static int
4521 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4522 		  struct netlink_ext_ack *extack)
4523 {
4524 	struct net *net = sock_net(skb->sk);
4525 	struct ifaddrmsg *ifm;
4526 	struct nlattr *tb[IFA_MAX+1];
4527 	struct in6_addr *pfx, *peer_pfx;
4528 	u32 ifa_flags;
4529 	int err;
4530 
4531 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4532 			  extack);
4533 	if (err < 0)
4534 		return err;
4535 
4536 	ifm = nlmsg_data(nlh);
4537 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4538 	if (!pfx)
4539 		return -EINVAL;
4540 
4541 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4542 
4543 	/* We ignore other flags so far. */
4544 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4545 
4546 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4547 			      ifm->ifa_prefixlen);
4548 }
4549 
4550 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4551 			       unsigned long expires, u32 flags)
4552 {
4553 	struct fib6_info *f6i;
4554 	u32 prio;
4555 
4556 	f6i = addrconf_get_prefix_route(&ifp->addr,
4557 					ifp->prefix_len,
4558 					ifp->idev->dev,
4559 					0, RTF_GATEWAY | RTF_DEFAULT);
4560 	if (!f6i)
4561 		return -ENOENT;
4562 
4563 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4564 	if (f6i->fib6_metric != prio) {
4565 		/* delete old one */
4566 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4567 
4568 		/* add new one */
4569 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4570 				      ifp->rt_priority, ifp->idev->dev,
4571 				      expires, flags, GFP_KERNEL);
4572 	} else {
4573 		if (!expires)
4574 			fib6_clean_expires(f6i);
4575 		else
4576 			fib6_set_expires(f6i, expires);
4577 
4578 		fib6_info_release(f6i);
4579 	}
4580 
4581 	return 0;
4582 }
4583 
4584 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4585 {
4586 	u32 flags;
4587 	clock_t expires;
4588 	unsigned long timeout;
4589 	bool was_managetempaddr;
4590 	bool had_prefixroute;
4591 
4592 	ASSERT_RTNL();
4593 
4594 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4595 		return -EINVAL;
4596 
4597 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4598 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4599 		return -EINVAL;
4600 
4601 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4602 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4603 
4604 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4605 	if (addrconf_finite_timeout(timeout)) {
4606 		expires = jiffies_to_clock_t(timeout * HZ);
4607 		cfg->valid_lft = timeout;
4608 		flags = RTF_EXPIRES;
4609 	} else {
4610 		expires = 0;
4611 		flags = 0;
4612 		cfg->ifa_flags |= IFA_F_PERMANENT;
4613 	}
4614 
4615 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4616 	if (addrconf_finite_timeout(timeout)) {
4617 		if (timeout == 0)
4618 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4619 		cfg->preferred_lft = timeout;
4620 	}
4621 
4622 	spin_lock_bh(&ifp->lock);
4623 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4624 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4625 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4626 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4627 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4628 			IFA_F_NOPREFIXROUTE);
4629 	ifp->flags |= cfg->ifa_flags;
4630 	ifp->tstamp = jiffies;
4631 	ifp->valid_lft = cfg->valid_lft;
4632 	ifp->prefered_lft = cfg->preferred_lft;
4633 
4634 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4635 		ifp->rt_priority = cfg->rt_priority;
4636 
4637 	spin_unlock_bh(&ifp->lock);
4638 	if (!(ifp->flags&IFA_F_TENTATIVE))
4639 		ipv6_ifa_notify(0, ifp);
4640 
4641 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4642 		int rc = -ENOENT;
4643 
4644 		if (had_prefixroute)
4645 			rc = modify_prefix_route(ifp, expires, flags);
4646 
4647 		/* prefix route could have been deleted; if so restore it */
4648 		if (rc == -ENOENT) {
4649 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4650 					      ifp->rt_priority, ifp->idev->dev,
4651 					      expires, flags, GFP_KERNEL);
4652 		}
4653 	} else if (had_prefixroute) {
4654 		enum cleanup_prefix_rt_t action;
4655 		unsigned long rt_expires;
4656 
4657 		write_lock_bh(&ifp->idev->lock);
4658 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4659 		write_unlock_bh(&ifp->idev->lock);
4660 
4661 		if (action != CLEANUP_PREFIX_RT_NOP) {
4662 			cleanup_prefix_route(ifp, rt_expires,
4663 				action == CLEANUP_PREFIX_RT_DEL);
4664 		}
4665 	}
4666 
4667 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4668 		if (was_managetempaddr &&
4669 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4670 			cfg->valid_lft = 0;
4671 			cfg->preferred_lft = 0;
4672 		}
4673 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4674 				 cfg->preferred_lft, !was_managetempaddr,
4675 				 jiffies);
4676 	}
4677 
4678 	addrconf_verify_rtnl();
4679 
4680 	return 0;
4681 }
4682 
4683 static int
4684 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4685 		  struct netlink_ext_ack *extack)
4686 {
4687 	struct net *net = sock_net(skb->sk);
4688 	struct ifaddrmsg *ifm;
4689 	struct nlattr *tb[IFA_MAX+1];
4690 	struct in6_addr *peer_pfx;
4691 	struct inet6_ifaddr *ifa;
4692 	struct net_device *dev;
4693 	struct inet6_dev *idev;
4694 	struct ifa6_config cfg;
4695 	int err;
4696 
4697 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4698 			  extack);
4699 	if (err < 0)
4700 		return err;
4701 
4702 	memset(&cfg, 0, sizeof(cfg));
4703 
4704 	ifm = nlmsg_data(nlh);
4705 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4706 	if (!cfg.pfx)
4707 		return -EINVAL;
4708 
4709 	cfg.peer_pfx = peer_pfx;
4710 	cfg.plen = ifm->ifa_prefixlen;
4711 	if (tb[IFA_RT_PRIORITY])
4712 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4713 
4714 	cfg.valid_lft = INFINITY_LIFE_TIME;
4715 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4716 
4717 	if (tb[IFA_CACHEINFO]) {
4718 		struct ifa_cacheinfo *ci;
4719 
4720 		ci = nla_data(tb[IFA_CACHEINFO]);
4721 		cfg.valid_lft = ci->ifa_valid;
4722 		cfg.preferred_lft = ci->ifa_prefered;
4723 	}
4724 
4725 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4726 	if (!dev)
4727 		return -ENODEV;
4728 
4729 	if (tb[IFA_FLAGS])
4730 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4731 	else
4732 		cfg.ifa_flags = ifm->ifa_flags;
4733 
4734 	/* We ignore other flags so far. */
4735 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4736 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4737 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4738 
4739 	idev = ipv6_find_idev(dev);
4740 	if (!idev)
4741 		return -ENOBUFS;
4742 
4743 	if (!ipv6_allow_optimistic_dad(net, idev))
4744 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4745 
4746 	if (cfg.ifa_flags & IFA_F_NODAD &&
4747 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4748 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4749 		return -EINVAL;
4750 	}
4751 
4752 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4753 	if (!ifa) {
4754 		/*
4755 		 * It would be best to check for !NLM_F_CREATE here but
4756 		 * userspace already relies on not having to provide this.
4757 		 */
4758 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4759 	}
4760 
4761 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4762 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4763 		err = -EEXIST;
4764 	else
4765 		err = inet6_addr_modify(ifa, &cfg);
4766 
4767 	in6_ifa_put(ifa);
4768 
4769 	return err;
4770 }
4771 
4772 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4773 			  u8 scope, int ifindex)
4774 {
4775 	struct ifaddrmsg *ifm;
4776 
4777 	ifm = nlmsg_data(nlh);
4778 	ifm->ifa_family = AF_INET6;
4779 	ifm->ifa_prefixlen = prefixlen;
4780 	ifm->ifa_flags = flags;
4781 	ifm->ifa_scope = scope;
4782 	ifm->ifa_index = ifindex;
4783 }
4784 
4785 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4786 			 unsigned long tstamp, u32 preferred, u32 valid)
4787 {
4788 	struct ifa_cacheinfo ci;
4789 
4790 	ci.cstamp = cstamp_delta(cstamp);
4791 	ci.tstamp = cstamp_delta(tstamp);
4792 	ci.ifa_prefered = preferred;
4793 	ci.ifa_valid = valid;
4794 
4795 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4796 }
4797 
4798 static inline int rt_scope(int ifa_scope)
4799 {
4800 	if (ifa_scope & IFA_HOST)
4801 		return RT_SCOPE_HOST;
4802 	else if (ifa_scope & IFA_LINK)
4803 		return RT_SCOPE_LINK;
4804 	else if (ifa_scope & IFA_SITE)
4805 		return RT_SCOPE_SITE;
4806 	else
4807 		return RT_SCOPE_UNIVERSE;
4808 }
4809 
4810 static inline int inet6_ifaddr_msgsize(void)
4811 {
4812 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4813 	       + nla_total_size(16) /* IFA_LOCAL */
4814 	       + nla_total_size(16) /* IFA_ADDRESS */
4815 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4816 	       + nla_total_size(4)  /* IFA_FLAGS */
4817 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4818 }
4819 
4820 enum addr_type_t {
4821 	UNICAST_ADDR,
4822 	MULTICAST_ADDR,
4823 	ANYCAST_ADDR,
4824 };
4825 
4826 struct inet6_fill_args {
4827 	u32 portid;
4828 	u32 seq;
4829 	int event;
4830 	unsigned int flags;
4831 	int netnsid;
4832 	int ifindex;
4833 	enum addr_type_t type;
4834 };
4835 
4836 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4837 			     struct inet6_fill_args *args)
4838 {
4839 	struct nlmsghdr  *nlh;
4840 	u32 preferred, valid;
4841 
4842 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4843 			sizeof(struct ifaddrmsg), args->flags);
4844 	if (!nlh)
4845 		return -EMSGSIZE;
4846 
4847 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4848 		      ifa->idev->dev->ifindex);
4849 
4850 	if (args->netnsid >= 0 &&
4851 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4852 		goto error;
4853 
4854 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4855 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4856 		preferred = ifa->prefered_lft;
4857 		valid = ifa->valid_lft;
4858 		if (preferred != INFINITY_LIFE_TIME) {
4859 			long tval = (jiffies - ifa->tstamp)/HZ;
4860 			if (preferred > tval)
4861 				preferred -= tval;
4862 			else
4863 				preferred = 0;
4864 			if (valid != INFINITY_LIFE_TIME) {
4865 				if (valid > tval)
4866 					valid -= tval;
4867 				else
4868 					valid = 0;
4869 			}
4870 		}
4871 	} else {
4872 		preferred = INFINITY_LIFE_TIME;
4873 		valid = INFINITY_LIFE_TIME;
4874 	}
4875 
4876 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4877 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4878 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4879 			goto error;
4880 	} else
4881 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4882 			goto error;
4883 
4884 	if (ifa->rt_priority &&
4885 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4886 		goto error;
4887 
4888 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4889 		goto error;
4890 
4891 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4892 		goto error;
4893 
4894 	nlmsg_end(skb, nlh);
4895 	return 0;
4896 
4897 error:
4898 	nlmsg_cancel(skb, nlh);
4899 	return -EMSGSIZE;
4900 }
4901 
4902 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4903 			       struct inet6_fill_args *args)
4904 {
4905 	struct nlmsghdr  *nlh;
4906 	u8 scope = RT_SCOPE_UNIVERSE;
4907 	int ifindex = ifmca->idev->dev->ifindex;
4908 
4909 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4910 		scope = RT_SCOPE_SITE;
4911 
4912 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4913 			sizeof(struct ifaddrmsg), args->flags);
4914 	if (!nlh)
4915 		return -EMSGSIZE;
4916 
4917 	if (args->netnsid >= 0 &&
4918 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4919 		return -EMSGSIZE;
4920 
4921 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4922 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4923 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4924 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4925 		nlmsg_cancel(skb, nlh);
4926 		return -EMSGSIZE;
4927 	}
4928 
4929 	nlmsg_end(skb, nlh);
4930 	return 0;
4931 }
4932 
4933 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4934 			       struct inet6_fill_args *args)
4935 {
4936 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4937 	int ifindex = dev ? dev->ifindex : 1;
4938 	struct nlmsghdr  *nlh;
4939 	u8 scope = RT_SCOPE_UNIVERSE;
4940 
4941 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4942 		scope = RT_SCOPE_SITE;
4943 
4944 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4945 			sizeof(struct ifaddrmsg), args->flags);
4946 	if (!nlh)
4947 		return -EMSGSIZE;
4948 
4949 	if (args->netnsid >= 0 &&
4950 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4951 		return -EMSGSIZE;
4952 
4953 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4954 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4955 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4956 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4957 		nlmsg_cancel(skb, nlh);
4958 		return -EMSGSIZE;
4959 	}
4960 
4961 	nlmsg_end(skb, nlh);
4962 	return 0;
4963 }
4964 
4965 /* called with rcu_read_lock() */
4966 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4967 			  struct netlink_callback *cb, int s_ip_idx,
4968 			  struct inet6_fill_args *fillargs)
4969 {
4970 	struct ifmcaddr6 *ifmca;
4971 	struct ifacaddr6 *ifaca;
4972 	int ip_idx = 0;
4973 	int err = 1;
4974 
4975 	read_lock_bh(&idev->lock);
4976 	switch (fillargs->type) {
4977 	case UNICAST_ADDR: {
4978 		struct inet6_ifaddr *ifa;
4979 		fillargs->event = RTM_NEWADDR;
4980 
4981 		/* unicast address incl. temp addr */
4982 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4983 			if (ip_idx < s_ip_idx)
4984 				goto next;
4985 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
4986 			if (err < 0)
4987 				break;
4988 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4989 next:
4990 			ip_idx++;
4991 		}
4992 		break;
4993 	}
4994 	case MULTICAST_ADDR:
4995 		fillargs->event = RTM_GETMULTICAST;
4996 
4997 		/* multicast address */
4998 		for (ifmca = idev->mc_list; ifmca;
4999 		     ifmca = ifmca->next, ip_idx++) {
5000 			if (ip_idx < s_ip_idx)
5001 				continue;
5002 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5003 			if (err < 0)
5004 				break;
5005 		}
5006 		break;
5007 	case ANYCAST_ADDR:
5008 		fillargs->event = RTM_GETANYCAST;
5009 		/* anycast address */
5010 		for (ifaca = idev->ac_list; ifaca;
5011 		     ifaca = ifaca->aca_next, ip_idx++) {
5012 			if (ip_idx < s_ip_idx)
5013 				continue;
5014 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5015 			if (err < 0)
5016 				break;
5017 		}
5018 		break;
5019 	default:
5020 		break;
5021 	}
5022 	read_unlock_bh(&idev->lock);
5023 	cb->args[2] = ip_idx;
5024 	return err;
5025 }
5026 
5027 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5028 				       struct inet6_fill_args *fillargs,
5029 				       struct net **tgt_net, struct sock *sk,
5030 				       struct netlink_callback *cb)
5031 {
5032 	struct netlink_ext_ack *extack = cb->extack;
5033 	struct nlattr *tb[IFA_MAX+1];
5034 	struct ifaddrmsg *ifm;
5035 	int err, i;
5036 
5037 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5038 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5039 		return -EINVAL;
5040 	}
5041 
5042 	ifm = nlmsg_data(nlh);
5043 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5044 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5045 		return -EINVAL;
5046 	}
5047 
5048 	fillargs->ifindex = ifm->ifa_index;
5049 	if (fillargs->ifindex) {
5050 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5051 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5052 	}
5053 
5054 	err = nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5055 				 ifa_ipv6_policy, extack);
5056 	if (err < 0)
5057 		return err;
5058 
5059 	for (i = 0; i <= IFA_MAX; ++i) {
5060 		if (!tb[i])
5061 			continue;
5062 
5063 		if (i == IFA_TARGET_NETNSID) {
5064 			struct net *net;
5065 
5066 			fillargs->netnsid = nla_get_s32(tb[i]);
5067 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5068 			if (IS_ERR(net)) {
5069 				fillargs->netnsid = -1;
5070 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5071 				return PTR_ERR(net);
5072 			}
5073 			*tgt_net = net;
5074 		} else {
5075 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5076 			return -EINVAL;
5077 		}
5078 	}
5079 
5080 	return 0;
5081 }
5082 
5083 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5084 			   enum addr_type_t type)
5085 {
5086 	const struct nlmsghdr *nlh = cb->nlh;
5087 	struct inet6_fill_args fillargs = {
5088 		.portid = NETLINK_CB(cb->skb).portid,
5089 		.seq = cb->nlh->nlmsg_seq,
5090 		.flags = NLM_F_MULTI,
5091 		.netnsid = -1,
5092 		.type = type,
5093 	};
5094 	struct net *net = sock_net(skb->sk);
5095 	struct net *tgt_net = net;
5096 	int idx, s_idx, s_ip_idx;
5097 	int h, s_h;
5098 	struct net_device *dev;
5099 	struct inet6_dev *idev;
5100 	struct hlist_head *head;
5101 	int err = 0;
5102 
5103 	s_h = cb->args[0];
5104 	s_idx = idx = cb->args[1];
5105 	s_ip_idx = cb->args[2];
5106 
5107 	if (cb->strict_check) {
5108 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5109 						  skb->sk, cb);
5110 		if (err < 0)
5111 			goto put_tgt_net;
5112 
5113 		err = 0;
5114 		if (fillargs.ifindex) {
5115 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5116 			if (!dev) {
5117 				err = -ENODEV;
5118 				goto put_tgt_net;
5119 			}
5120 			idev = __in6_dev_get(dev);
5121 			if (idev) {
5122 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5123 						     &fillargs);
5124 				if (err > 0)
5125 					err = 0;
5126 			}
5127 			goto put_tgt_net;
5128 		}
5129 	}
5130 
5131 	rcu_read_lock();
5132 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5133 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5134 		idx = 0;
5135 		head = &tgt_net->dev_index_head[h];
5136 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5137 			if (idx < s_idx)
5138 				goto cont;
5139 			if (h > s_h || idx > s_idx)
5140 				s_ip_idx = 0;
5141 			idev = __in6_dev_get(dev);
5142 			if (!idev)
5143 				goto cont;
5144 
5145 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5146 					   &fillargs) < 0)
5147 				goto done;
5148 cont:
5149 			idx++;
5150 		}
5151 	}
5152 done:
5153 	rcu_read_unlock();
5154 	cb->args[0] = h;
5155 	cb->args[1] = idx;
5156 put_tgt_net:
5157 	if (fillargs.netnsid >= 0)
5158 		put_net(tgt_net);
5159 
5160 	return skb->len ? : err;
5161 }
5162 
5163 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5164 {
5165 	enum addr_type_t type = UNICAST_ADDR;
5166 
5167 	return inet6_dump_addr(skb, cb, type);
5168 }
5169 
5170 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5171 {
5172 	enum addr_type_t type = MULTICAST_ADDR;
5173 
5174 	return inet6_dump_addr(skb, cb, type);
5175 }
5176 
5177 
5178 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5179 {
5180 	enum addr_type_t type = ANYCAST_ADDR;
5181 
5182 	return inet6_dump_addr(skb, cb, type);
5183 }
5184 
5185 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5186 			     struct netlink_ext_ack *extack)
5187 {
5188 	struct net *net = sock_net(in_skb->sk);
5189 	struct inet6_fill_args fillargs = {
5190 		.portid = NETLINK_CB(in_skb).portid,
5191 		.seq = nlh->nlmsg_seq,
5192 		.event = RTM_NEWADDR,
5193 		.flags = 0,
5194 		.netnsid = -1,
5195 	};
5196 	struct net *tgt_net = net;
5197 	struct ifaddrmsg *ifm;
5198 	struct nlattr *tb[IFA_MAX+1];
5199 	struct in6_addr *addr = NULL, *peer;
5200 	struct net_device *dev = NULL;
5201 	struct inet6_ifaddr *ifa;
5202 	struct sk_buff *skb;
5203 	int err;
5204 
5205 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
5206 			  extack);
5207 	if (err < 0)
5208 		return err;
5209 
5210 	if (tb[IFA_TARGET_NETNSID]) {
5211 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5212 
5213 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5214 						  fillargs.netnsid);
5215 		if (IS_ERR(tgt_net))
5216 			return PTR_ERR(tgt_net);
5217 	}
5218 
5219 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5220 	if (!addr)
5221 		return -EINVAL;
5222 
5223 	ifm = nlmsg_data(nlh);
5224 	if (ifm->ifa_index)
5225 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5226 
5227 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5228 	if (!ifa) {
5229 		err = -EADDRNOTAVAIL;
5230 		goto errout;
5231 	}
5232 
5233 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5234 	if (!skb) {
5235 		err = -ENOBUFS;
5236 		goto errout_ifa;
5237 	}
5238 
5239 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5240 	if (err < 0) {
5241 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5242 		WARN_ON(err == -EMSGSIZE);
5243 		kfree_skb(skb);
5244 		goto errout_ifa;
5245 	}
5246 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5247 errout_ifa:
5248 	in6_ifa_put(ifa);
5249 errout:
5250 	if (dev)
5251 		dev_put(dev);
5252 	if (fillargs.netnsid >= 0)
5253 		put_net(tgt_net);
5254 
5255 	return err;
5256 }
5257 
5258 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5259 {
5260 	struct sk_buff *skb;
5261 	struct net *net = dev_net(ifa->idev->dev);
5262 	struct inet6_fill_args fillargs = {
5263 		.portid = 0,
5264 		.seq = 0,
5265 		.event = event,
5266 		.flags = 0,
5267 		.netnsid = -1,
5268 	};
5269 	int err = -ENOBUFS;
5270 
5271 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5272 	if (!skb)
5273 		goto errout;
5274 
5275 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5276 	if (err < 0) {
5277 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5278 		WARN_ON(err == -EMSGSIZE);
5279 		kfree_skb(skb);
5280 		goto errout;
5281 	}
5282 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5283 	return;
5284 errout:
5285 	if (err < 0)
5286 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5287 }
5288 
5289 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5290 				__s32 *array, int bytes)
5291 {
5292 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5293 
5294 	memset(array, 0, bytes);
5295 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5296 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5297 	array[DEVCONF_MTU6] = cnf->mtu6;
5298 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5299 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5300 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5301 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5302 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5303 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5304 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5305 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5306 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5307 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5308 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5309 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5310 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5311 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5312 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5313 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5314 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5315 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5316 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5317 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5318 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5319 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5320 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5321 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5322 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5323 #ifdef CONFIG_IPV6_ROUTER_PREF
5324 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5325 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5326 		jiffies_to_msecs(cnf->rtr_probe_interval);
5327 #ifdef CONFIG_IPV6_ROUTE_INFO
5328 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5329 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5330 #endif
5331 #endif
5332 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5333 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5334 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5335 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5336 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5337 #endif
5338 #ifdef CONFIG_IPV6_MROUTE
5339 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5340 #endif
5341 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5342 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5343 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5344 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5345 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5346 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5347 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5348 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5349 	/* we omit DEVCONF_STABLE_SECRET for now */
5350 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5351 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5352 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5353 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5354 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5355 #ifdef CONFIG_IPV6_SEG6_HMAC
5356 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5357 #endif
5358 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5359 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5360 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5361 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5362 }
5363 
5364 static inline size_t inet6_ifla6_size(void)
5365 {
5366 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5367 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5368 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5369 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5370 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5371 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5372 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5373 	     + 0;
5374 }
5375 
5376 static inline size_t inet6_if_nlmsg_size(void)
5377 {
5378 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5379 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5380 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5381 	       + nla_total_size(4) /* IFLA_MTU */
5382 	       + nla_total_size(4) /* IFLA_LINK */
5383 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5384 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5385 }
5386 
5387 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5388 					int bytes)
5389 {
5390 	int i;
5391 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5392 	BUG_ON(pad < 0);
5393 
5394 	/* Use put_unaligned() because stats may not be aligned for u64. */
5395 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5396 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5397 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5398 
5399 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5400 }
5401 
5402 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5403 					int bytes, size_t syncpoff)
5404 {
5405 	int i, c;
5406 	u64 buff[IPSTATS_MIB_MAX];
5407 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5408 
5409 	BUG_ON(pad < 0);
5410 
5411 	memset(buff, 0, sizeof(buff));
5412 	buff[0] = IPSTATS_MIB_MAX;
5413 
5414 	for_each_possible_cpu(c) {
5415 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5416 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5417 	}
5418 
5419 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5420 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5421 }
5422 
5423 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5424 			     int bytes)
5425 {
5426 	switch (attrtype) {
5427 	case IFLA_INET6_STATS:
5428 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5429 				     offsetof(struct ipstats_mib, syncp));
5430 		break;
5431 	case IFLA_INET6_ICMP6STATS:
5432 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5433 		break;
5434 	}
5435 }
5436 
5437 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5438 				  u32 ext_filter_mask)
5439 {
5440 	struct nlattr *nla;
5441 	struct ifla_cacheinfo ci;
5442 
5443 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5444 		goto nla_put_failure;
5445 	ci.max_reasm_len = IPV6_MAXPLEN;
5446 	ci.tstamp = cstamp_delta(idev->tstamp);
5447 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5448 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5449 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5450 		goto nla_put_failure;
5451 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5452 	if (!nla)
5453 		goto nla_put_failure;
5454 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5455 
5456 	/* XXX - MC not implemented */
5457 
5458 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5459 		return 0;
5460 
5461 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5462 	if (!nla)
5463 		goto nla_put_failure;
5464 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5465 
5466 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5467 	if (!nla)
5468 		goto nla_put_failure;
5469 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5470 
5471 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5472 	if (!nla)
5473 		goto nla_put_failure;
5474 
5475 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5476 		goto nla_put_failure;
5477 
5478 	read_lock_bh(&idev->lock);
5479 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5480 	read_unlock_bh(&idev->lock);
5481 
5482 	return 0;
5483 
5484 nla_put_failure:
5485 	return -EMSGSIZE;
5486 }
5487 
5488 static size_t inet6_get_link_af_size(const struct net_device *dev,
5489 				     u32 ext_filter_mask)
5490 {
5491 	if (!__in6_dev_get(dev))
5492 		return 0;
5493 
5494 	return inet6_ifla6_size();
5495 }
5496 
5497 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5498 			      u32 ext_filter_mask)
5499 {
5500 	struct inet6_dev *idev = __in6_dev_get(dev);
5501 
5502 	if (!idev)
5503 		return -ENODATA;
5504 
5505 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5506 		return -EMSGSIZE;
5507 
5508 	return 0;
5509 }
5510 
5511 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5512 {
5513 	struct inet6_ifaddr *ifp;
5514 	struct net_device *dev = idev->dev;
5515 	bool clear_token, update_rs = false;
5516 	struct in6_addr ll_addr;
5517 
5518 	ASSERT_RTNL();
5519 
5520 	if (!token)
5521 		return -EINVAL;
5522 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5523 		return -EINVAL;
5524 	if (!ipv6_accept_ra(idev))
5525 		return -EINVAL;
5526 	if (idev->cnf.rtr_solicits == 0)
5527 		return -EINVAL;
5528 
5529 	write_lock_bh(&idev->lock);
5530 
5531 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5532 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5533 
5534 	write_unlock_bh(&idev->lock);
5535 
5536 	clear_token = ipv6_addr_any(token);
5537 	if (clear_token)
5538 		goto update_lft;
5539 
5540 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5541 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5542 			     IFA_F_OPTIMISTIC)) {
5543 		/* If we're not ready, then normal ifup will take care
5544 		 * of this. Otherwise, we need to request our rs here.
5545 		 */
5546 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5547 		update_rs = true;
5548 	}
5549 
5550 update_lft:
5551 	write_lock_bh(&idev->lock);
5552 
5553 	if (update_rs) {
5554 		idev->if_flags |= IF_RS_SENT;
5555 		idev->rs_interval = rfc3315_s14_backoff_init(
5556 			idev->cnf.rtr_solicit_interval);
5557 		idev->rs_probes = 1;
5558 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5559 	}
5560 
5561 	/* Well, that's kinda nasty ... */
5562 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5563 		spin_lock(&ifp->lock);
5564 		if (ifp->tokenized) {
5565 			ifp->valid_lft = 0;
5566 			ifp->prefered_lft = 0;
5567 		}
5568 		spin_unlock(&ifp->lock);
5569 	}
5570 
5571 	write_unlock_bh(&idev->lock);
5572 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5573 	addrconf_verify_rtnl();
5574 	return 0;
5575 }
5576 
5577 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5578 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5579 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5580 };
5581 
5582 static int inet6_validate_link_af(const struct net_device *dev,
5583 				  const struct nlattr *nla)
5584 {
5585 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5586 
5587 	if (dev && !__in6_dev_get(dev))
5588 		return -EAFNOSUPPORT;
5589 
5590 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5591 				NULL);
5592 }
5593 
5594 static int check_addr_gen_mode(int mode)
5595 {
5596 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5597 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5598 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5599 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5600 		return -EINVAL;
5601 	return 1;
5602 }
5603 
5604 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5605 				int mode)
5606 {
5607 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5608 	    !idev->cnf.stable_secret.initialized &&
5609 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5610 		return -EINVAL;
5611 	return 1;
5612 }
5613 
5614 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5615 {
5616 	int err = -EINVAL;
5617 	struct inet6_dev *idev = __in6_dev_get(dev);
5618 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5619 
5620 	if (!idev)
5621 		return -EAFNOSUPPORT;
5622 
5623 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5624 		BUG();
5625 
5626 	if (tb[IFLA_INET6_TOKEN]) {
5627 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5628 		if (err)
5629 			return err;
5630 	}
5631 
5632 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5633 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5634 
5635 		if (check_addr_gen_mode(mode) < 0 ||
5636 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5637 			return -EINVAL;
5638 
5639 		idev->cnf.addr_gen_mode = mode;
5640 		err = 0;
5641 	}
5642 
5643 	return err;
5644 }
5645 
5646 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5647 			     u32 portid, u32 seq, int event, unsigned int flags)
5648 {
5649 	struct net_device *dev = idev->dev;
5650 	struct ifinfomsg *hdr;
5651 	struct nlmsghdr *nlh;
5652 	void *protoinfo;
5653 
5654 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5655 	if (!nlh)
5656 		return -EMSGSIZE;
5657 
5658 	hdr = nlmsg_data(nlh);
5659 	hdr->ifi_family = AF_INET6;
5660 	hdr->__ifi_pad = 0;
5661 	hdr->ifi_type = dev->type;
5662 	hdr->ifi_index = dev->ifindex;
5663 	hdr->ifi_flags = dev_get_flags(dev);
5664 	hdr->ifi_change = 0;
5665 
5666 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5667 	    (dev->addr_len &&
5668 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5669 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5670 	    (dev->ifindex != dev_get_iflink(dev) &&
5671 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5672 	    nla_put_u8(skb, IFLA_OPERSTATE,
5673 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5674 		goto nla_put_failure;
5675 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5676 	if (!protoinfo)
5677 		goto nla_put_failure;
5678 
5679 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5680 		goto nla_put_failure;
5681 
5682 	nla_nest_end(skb, protoinfo);
5683 	nlmsg_end(skb, nlh);
5684 	return 0;
5685 
5686 nla_put_failure:
5687 	nlmsg_cancel(skb, nlh);
5688 	return -EMSGSIZE;
5689 }
5690 
5691 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5692 				   struct netlink_ext_ack *extack)
5693 {
5694 	struct ifinfomsg *ifm;
5695 
5696 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5697 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5698 		return -EINVAL;
5699 	}
5700 
5701 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5702 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5703 		return -EINVAL;
5704 	}
5705 
5706 	ifm = nlmsg_data(nlh);
5707 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5708 	    ifm->ifi_change || ifm->ifi_index) {
5709 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5710 		return -EINVAL;
5711 	}
5712 
5713 	return 0;
5714 }
5715 
5716 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5717 {
5718 	struct net *net = sock_net(skb->sk);
5719 	int h, s_h;
5720 	int idx = 0, s_idx;
5721 	struct net_device *dev;
5722 	struct inet6_dev *idev;
5723 	struct hlist_head *head;
5724 
5725 	/* only requests using strict checking can pass data to
5726 	 * influence the dump
5727 	 */
5728 	if (cb->strict_check) {
5729 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5730 
5731 		if (err < 0)
5732 			return err;
5733 	}
5734 
5735 	s_h = cb->args[0];
5736 	s_idx = cb->args[1];
5737 
5738 	rcu_read_lock();
5739 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5740 		idx = 0;
5741 		head = &net->dev_index_head[h];
5742 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5743 			if (idx < s_idx)
5744 				goto cont;
5745 			idev = __in6_dev_get(dev);
5746 			if (!idev)
5747 				goto cont;
5748 			if (inet6_fill_ifinfo(skb, idev,
5749 					      NETLINK_CB(cb->skb).portid,
5750 					      cb->nlh->nlmsg_seq,
5751 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5752 				goto out;
5753 cont:
5754 			idx++;
5755 		}
5756 	}
5757 out:
5758 	rcu_read_unlock();
5759 	cb->args[1] = idx;
5760 	cb->args[0] = h;
5761 
5762 	return skb->len;
5763 }
5764 
5765 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5766 {
5767 	struct sk_buff *skb;
5768 	struct net *net = dev_net(idev->dev);
5769 	int err = -ENOBUFS;
5770 
5771 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5772 	if (!skb)
5773 		goto errout;
5774 
5775 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5776 	if (err < 0) {
5777 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5778 		WARN_ON(err == -EMSGSIZE);
5779 		kfree_skb(skb);
5780 		goto errout;
5781 	}
5782 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5783 	return;
5784 errout:
5785 	if (err < 0)
5786 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5787 }
5788 
5789 static inline size_t inet6_prefix_nlmsg_size(void)
5790 {
5791 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5792 	       + nla_total_size(sizeof(struct in6_addr))
5793 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5794 }
5795 
5796 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5797 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5798 			     int event, unsigned int flags)
5799 {
5800 	struct prefixmsg *pmsg;
5801 	struct nlmsghdr *nlh;
5802 	struct prefix_cacheinfo	ci;
5803 
5804 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5805 	if (!nlh)
5806 		return -EMSGSIZE;
5807 
5808 	pmsg = nlmsg_data(nlh);
5809 	pmsg->prefix_family = AF_INET6;
5810 	pmsg->prefix_pad1 = 0;
5811 	pmsg->prefix_pad2 = 0;
5812 	pmsg->prefix_ifindex = idev->dev->ifindex;
5813 	pmsg->prefix_len = pinfo->prefix_len;
5814 	pmsg->prefix_type = pinfo->type;
5815 	pmsg->prefix_pad3 = 0;
5816 	pmsg->prefix_flags = 0;
5817 	if (pinfo->onlink)
5818 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5819 	if (pinfo->autoconf)
5820 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5821 
5822 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5823 		goto nla_put_failure;
5824 	ci.preferred_time = ntohl(pinfo->prefered);
5825 	ci.valid_time = ntohl(pinfo->valid);
5826 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5827 		goto nla_put_failure;
5828 	nlmsg_end(skb, nlh);
5829 	return 0;
5830 
5831 nla_put_failure:
5832 	nlmsg_cancel(skb, nlh);
5833 	return -EMSGSIZE;
5834 }
5835 
5836 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5837 			 struct prefix_info *pinfo)
5838 {
5839 	struct sk_buff *skb;
5840 	struct net *net = dev_net(idev->dev);
5841 	int err = -ENOBUFS;
5842 
5843 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5844 	if (!skb)
5845 		goto errout;
5846 
5847 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5848 	if (err < 0) {
5849 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5850 		WARN_ON(err == -EMSGSIZE);
5851 		kfree_skb(skb);
5852 		goto errout;
5853 	}
5854 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5855 	return;
5856 errout:
5857 	if (err < 0)
5858 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5859 }
5860 
5861 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5862 {
5863 	struct net *net = dev_net(ifp->idev->dev);
5864 
5865 	if (event)
5866 		ASSERT_RTNL();
5867 
5868 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5869 
5870 	switch (event) {
5871 	case RTM_NEWADDR:
5872 		/*
5873 		 * If the address was optimistic
5874 		 * we inserted the route at the start of
5875 		 * our DAD process, so we don't need
5876 		 * to do it again
5877 		 */
5878 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5879 			ip6_ins_rt(net, ifp->rt);
5880 		if (ifp->idev->cnf.forwarding)
5881 			addrconf_join_anycast(ifp);
5882 		if (!ipv6_addr_any(&ifp->peer_addr))
5883 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5884 					      ifp->idev->dev, 0, 0,
5885 					      GFP_ATOMIC);
5886 		break;
5887 	case RTM_DELADDR:
5888 		if (ifp->idev->cnf.forwarding)
5889 			addrconf_leave_anycast(ifp);
5890 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5891 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5892 			struct fib6_info *rt;
5893 
5894 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5895 						       ifp->idev->dev, 0, 0);
5896 			if (rt)
5897 				ip6_del_rt(net, rt);
5898 		}
5899 		if (ifp->rt) {
5900 			ip6_del_rt(net, ifp->rt);
5901 			ifp->rt = NULL;
5902 		}
5903 		rt_genid_bump_ipv6(net);
5904 		break;
5905 	}
5906 	atomic_inc(&net->ipv6.dev_addr_genid);
5907 }
5908 
5909 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5910 {
5911 	rcu_read_lock_bh();
5912 	if (likely(ifp->idev->dead == 0))
5913 		__ipv6_ifa_notify(event, ifp);
5914 	rcu_read_unlock_bh();
5915 }
5916 
5917 #ifdef CONFIG_SYSCTL
5918 
5919 static
5920 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5921 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5922 {
5923 	int *valp = ctl->data;
5924 	int val = *valp;
5925 	loff_t pos = *ppos;
5926 	struct ctl_table lctl;
5927 	int ret;
5928 
5929 	/*
5930 	 * ctl->data points to idev->cnf.forwarding, we should
5931 	 * not modify it until we get the rtnl lock.
5932 	 */
5933 	lctl = *ctl;
5934 	lctl.data = &val;
5935 
5936 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5937 
5938 	if (write)
5939 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5940 	if (ret)
5941 		*ppos = pos;
5942 	return ret;
5943 }
5944 
5945 static
5946 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5947 			void __user *buffer, size_t *lenp, loff_t *ppos)
5948 {
5949 	struct inet6_dev *idev = ctl->extra1;
5950 	int min_mtu = IPV6_MIN_MTU;
5951 	struct ctl_table lctl;
5952 
5953 	lctl = *ctl;
5954 	lctl.extra1 = &min_mtu;
5955 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5956 
5957 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5958 }
5959 
5960 static void dev_disable_change(struct inet6_dev *idev)
5961 {
5962 	struct netdev_notifier_info info;
5963 
5964 	if (!idev || !idev->dev)
5965 		return;
5966 
5967 	netdev_notifier_info_init(&info, idev->dev);
5968 	if (idev->cnf.disable_ipv6)
5969 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5970 	else
5971 		addrconf_notify(NULL, NETDEV_UP, &info);
5972 }
5973 
5974 static void addrconf_disable_change(struct net *net, __s32 newf)
5975 {
5976 	struct net_device *dev;
5977 	struct inet6_dev *idev;
5978 
5979 	for_each_netdev(net, dev) {
5980 		idev = __in6_dev_get(dev);
5981 		if (idev) {
5982 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5983 			idev->cnf.disable_ipv6 = newf;
5984 			if (changed)
5985 				dev_disable_change(idev);
5986 		}
5987 	}
5988 }
5989 
5990 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5991 {
5992 	struct net *net;
5993 	int old;
5994 
5995 	if (!rtnl_trylock())
5996 		return restart_syscall();
5997 
5998 	net = (struct net *)table->extra2;
5999 	old = *p;
6000 	*p = newf;
6001 
6002 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6003 		rtnl_unlock();
6004 		return 0;
6005 	}
6006 
6007 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6008 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6009 		addrconf_disable_change(net, newf);
6010 	} else if ((!newf) ^ (!old))
6011 		dev_disable_change((struct inet6_dev *)table->extra1);
6012 
6013 	rtnl_unlock();
6014 	return 0;
6015 }
6016 
6017 static
6018 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6019 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6020 {
6021 	int *valp = ctl->data;
6022 	int val = *valp;
6023 	loff_t pos = *ppos;
6024 	struct ctl_table lctl;
6025 	int ret;
6026 
6027 	/*
6028 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6029 	 * not modify it until we get the rtnl lock.
6030 	 */
6031 	lctl = *ctl;
6032 	lctl.data = &val;
6033 
6034 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6035 
6036 	if (write)
6037 		ret = addrconf_disable_ipv6(ctl, valp, val);
6038 	if (ret)
6039 		*ppos = pos;
6040 	return ret;
6041 }
6042 
6043 static
6044 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6045 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6046 {
6047 	int *valp = ctl->data;
6048 	int ret;
6049 	int old, new;
6050 
6051 	old = *valp;
6052 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6053 	new = *valp;
6054 
6055 	if (write && old != new) {
6056 		struct net *net = ctl->extra2;
6057 
6058 		if (!rtnl_trylock())
6059 			return restart_syscall();
6060 
6061 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6062 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6063 						     NETCONFA_PROXY_NEIGH,
6064 						     NETCONFA_IFINDEX_DEFAULT,
6065 						     net->ipv6.devconf_dflt);
6066 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6067 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6068 						     NETCONFA_PROXY_NEIGH,
6069 						     NETCONFA_IFINDEX_ALL,
6070 						     net->ipv6.devconf_all);
6071 		else {
6072 			struct inet6_dev *idev = ctl->extra1;
6073 
6074 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6075 						     NETCONFA_PROXY_NEIGH,
6076 						     idev->dev->ifindex,
6077 						     &idev->cnf);
6078 		}
6079 		rtnl_unlock();
6080 	}
6081 
6082 	return ret;
6083 }
6084 
6085 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6086 					 void __user *buffer, size_t *lenp,
6087 					 loff_t *ppos)
6088 {
6089 	int ret = 0;
6090 	u32 new_val;
6091 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6092 	struct net *net = (struct net *)ctl->extra2;
6093 	struct ctl_table tmp = {
6094 		.data = &new_val,
6095 		.maxlen = sizeof(new_val),
6096 		.mode = ctl->mode,
6097 	};
6098 
6099 	if (!rtnl_trylock())
6100 		return restart_syscall();
6101 
6102 	new_val = *((u32 *)ctl->data);
6103 
6104 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6105 	if (ret != 0)
6106 		goto out;
6107 
6108 	if (write) {
6109 		if (check_addr_gen_mode(new_val) < 0) {
6110 			ret = -EINVAL;
6111 			goto out;
6112 		}
6113 
6114 		if (idev) {
6115 			if (check_stable_privacy(idev, net, new_val) < 0) {
6116 				ret = -EINVAL;
6117 				goto out;
6118 			}
6119 
6120 			if (idev->cnf.addr_gen_mode != new_val) {
6121 				idev->cnf.addr_gen_mode = new_val;
6122 				addrconf_dev_config(idev->dev);
6123 			}
6124 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6125 			struct net_device *dev;
6126 
6127 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6128 			for_each_netdev(net, dev) {
6129 				idev = __in6_dev_get(dev);
6130 				if (idev &&
6131 				    idev->cnf.addr_gen_mode != new_val) {
6132 					idev->cnf.addr_gen_mode = new_val;
6133 					addrconf_dev_config(idev->dev);
6134 				}
6135 			}
6136 		}
6137 
6138 		*((u32 *)ctl->data) = new_val;
6139 	}
6140 
6141 out:
6142 	rtnl_unlock();
6143 
6144 	return ret;
6145 }
6146 
6147 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6148 					 void __user *buffer, size_t *lenp,
6149 					 loff_t *ppos)
6150 {
6151 	int err;
6152 	struct in6_addr addr;
6153 	char str[IPV6_MAX_STRLEN];
6154 	struct ctl_table lctl = *ctl;
6155 	struct net *net = ctl->extra2;
6156 	struct ipv6_stable_secret *secret = ctl->data;
6157 
6158 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6159 		return -EIO;
6160 
6161 	lctl.maxlen = IPV6_MAX_STRLEN;
6162 	lctl.data = str;
6163 
6164 	if (!rtnl_trylock())
6165 		return restart_syscall();
6166 
6167 	if (!write && !secret->initialized) {
6168 		err = -EIO;
6169 		goto out;
6170 	}
6171 
6172 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6173 	if (err >= sizeof(str)) {
6174 		err = -EIO;
6175 		goto out;
6176 	}
6177 
6178 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6179 	if (err || !write)
6180 		goto out;
6181 
6182 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6183 		err = -EIO;
6184 		goto out;
6185 	}
6186 
6187 	secret->initialized = true;
6188 	secret->secret = addr;
6189 
6190 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6191 		struct net_device *dev;
6192 
6193 		for_each_netdev(net, dev) {
6194 			struct inet6_dev *idev = __in6_dev_get(dev);
6195 
6196 			if (idev) {
6197 				idev->cnf.addr_gen_mode =
6198 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6199 			}
6200 		}
6201 	} else {
6202 		struct inet6_dev *idev = ctl->extra1;
6203 
6204 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6205 	}
6206 
6207 out:
6208 	rtnl_unlock();
6209 
6210 	return err;
6211 }
6212 
6213 static
6214 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6215 						int write,
6216 						void __user *buffer,
6217 						size_t *lenp,
6218 						loff_t *ppos)
6219 {
6220 	int *valp = ctl->data;
6221 	int val = *valp;
6222 	loff_t pos = *ppos;
6223 	struct ctl_table lctl;
6224 	int ret;
6225 
6226 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6227 	 * we should not modify it until we get the rtnl lock.
6228 	 */
6229 	lctl = *ctl;
6230 	lctl.data = &val;
6231 
6232 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6233 
6234 	if (write)
6235 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6236 	if (ret)
6237 		*ppos = pos;
6238 	return ret;
6239 }
6240 
6241 static
6242 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6243 {
6244 	if (rt) {
6245 		if (action)
6246 			rt->dst.flags |= DST_NOPOLICY;
6247 		else
6248 			rt->dst.flags &= ~DST_NOPOLICY;
6249 	}
6250 }
6251 
6252 static
6253 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6254 {
6255 	struct inet6_ifaddr *ifa;
6256 
6257 	read_lock_bh(&idev->lock);
6258 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6259 		spin_lock(&ifa->lock);
6260 		if (ifa->rt) {
6261 			struct fib6_info *rt = ifa->rt;
6262 			int cpu;
6263 
6264 			rcu_read_lock();
6265 			ifa->rt->dst_nopolicy = val ? true : false;
6266 			if (rt->rt6i_pcpu) {
6267 				for_each_possible_cpu(cpu) {
6268 					struct rt6_info **rtp;
6269 
6270 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6271 					addrconf_set_nopolicy(*rtp, val);
6272 				}
6273 			}
6274 			rcu_read_unlock();
6275 		}
6276 		spin_unlock(&ifa->lock);
6277 	}
6278 	read_unlock_bh(&idev->lock);
6279 }
6280 
6281 static
6282 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6283 {
6284 	struct inet6_dev *idev;
6285 	struct net *net;
6286 
6287 	if (!rtnl_trylock())
6288 		return restart_syscall();
6289 
6290 	*valp = val;
6291 
6292 	net = (struct net *)ctl->extra2;
6293 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6294 		rtnl_unlock();
6295 		return 0;
6296 	}
6297 
6298 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6299 		struct net_device *dev;
6300 
6301 		for_each_netdev(net, dev) {
6302 			idev = __in6_dev_get(dev);
6303 			if (idev)
6304 				addrconf_disable_policy_idev(idev, val);
6305 		}
6306 	} else {
6307 		idev = (struct inet6_dev *)ctl->extra1;
6308 		addrconf_disable_policy_idev(idev, val);
6309 	}
6310 
6311 	rtnl_unlock();
6312 	return 0;
6313 }
6314 
6315 static
6316 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6317 				   void __user *buffer, size_t *lenp,
6318 				   loff_t *ppos)
6319 {
6320 	int *valp = ctl->data;
6321 	int val = *valp;
6322 	loff_t pos = *ppos;
6323 	struct ctl_table lctl;
6324 	int ret;
6325 
6326 	lctl = *ctl;
6327 	lctl.data = &val;
6328 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6329 
6330 	if (write && (*valp != val))
6331 		ret = addrconf_disable_policy(ctl, valp, val);
6332 
6333 	if (ret)
6334 		*ppos = pos;
6335 
6336 	return ret;
6337 }
6338 
6339 static int minus_one = -1;
6340 static const int zero = 0;
6341 static const int one = 1;
6342 static const int two_five_five = 255;
6343 
6344 static const struct ctl_table addrconf_sysctl[] = {
6345 	{
6346 		.procname	= "forwarding",
6347 		.data		= &ipv6_devconf.forwarding,
6348 		.maxlen		= sizeof(int),
6349 		.mode		= 0644,
6350 		.proc_handler	= addrconf_sysctl_forward,
6351 	},
6352 	{
6353 		.procname	= "hop_limit",
6354 		.data		= &ipv6_devconf.hop_limit,
6355 		.maxlen		= sizeof(int),
6356 		.mode		= 0644,
6357 		.proc_handler	= proc_dointvec_minmax,
6358 		.extra1		= (void *)&one,
6359 		.extra2		= (void *)&two_five_five,
6360 	},
6361 	{
6362 		.procname	= "mtu",
6363 		.data		= &ipv6_devconf.mtu6,
6364 		.maxlen		= sizeof(int),
6365 		.mode		= 0644,
6366 		.proc_handler	= addrconf_sysctl_mtu,
6367 	},
6368 	{
6369 		.procname	= "accept_ra",
6370 		.data		= &ipv6_devconf.accept_ra,
6371 		.maxlen		= sizeof(int),
6372 		.mode		= 0644,
6373 		.proc_handler	= proc_dointvec,
6374 	},
6375 	{
6376 		.procname	= "accept_redirects",
6377 		.data		= &ipv6_devconf.accept_redirects,
6378 		.maxlen		= sizeof(int),
6379 		.mode		= 0644,
6380 		.proc_handler	= proc_dointvec,
6381 	},
6382 	{
6383 		.procname	= "autoconf",
6384 		.data		= &ipv6_devconf.autoconf,
6385 		.maxlen		= sizeof(int),
6386 		.mode		= 0644,
6387 		.proc_handler	= proc_dointvec,
6388 	},
6389 	{
6390 		.procname	= "dad_transmits",
6391 		.data		= &ipv6_devconf.dad_transmits,
6392 		.maxlen		= sizeof(int),
6393 		.mode		= 0644,
6394 		.proc_handler	= proc_dointvec,
6395 	},
6396 	{
6397 		.procname	= "router_solicitations",
6398 		.data		= &ipv6_devconf.rtr_solicits,
6399 		.maxlen		= sizeof(int),
6400 		.mode		= 0644,
6401 		.proc_handler	= proc_dointvec_minmax,
6402 		.extra1		= &minus_one,
6403 	},
6404 	{
6405 		.procname	= "router_solicitation_interval",
6406 		.data		= &ipv6_devconf.rtr_solicit_interval,
6407 		.maxlen		= sizeof(int),
6408 		.mode		= 0644,
6409 		.proc_handler	= proc_dointvec_jiffies,
6410 	},
6411 	{
6412 		.procname	= "router_solicitation_max_interval",
6413 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6414 		.maxlen		= sizeof(int),
6415 		.mode		= 0644,
6416 		.proc_handler	= proc_dointvec_jiffies,
6417 	},
6418 	{
6419 		.procname	= "router_solicitation_delay",
6420 		.data		= &ipv6_devconf.rtr_solicit_delay,
6421 		.maxlen		= sizeof(int),
6422 		.mode		= 0644,
6423 		.proc_handler	= proc_dointvec_jiffies,
6424 	},
6425 	{
6426 		.procname	= "force_mld_version",
6427 		.data		= &ipv6_devconf.force_mld_version,
6428 		.maxlen		= sizeof(int),
6429 		.mode		= 0644,
6430 		.proc_handler	= proc_dointvec,
6431 	},
6432 	{
6433 		.procname	= "mldv1_unsolicited_report_interval",
6434 		.data		=
6435 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6436 		.maxlen		= sizeof(int),
6437 		.mode		= 0644,
6438 		.proc_handler	= proc_dointvec_ms_jiffies,
6439 	},
6440 	{
6441 		.procname	= "mldv2_unsolicited_report_interval",
6442 		.data		=
6443 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6444 		.maxlen		= sizeof(int),
6445 		.mode		= 0644,
6446 		.proc_handler	= proc_dointvec_ms_jiffies,
6447 	},
6448 	{
6449 		.procname	= "use_tempaddr",
6450 		.data		= &ipv6_devconf.use_tempaddr,
6451 		.maxlen		= sizeof(int),
6452 		.mode		= 0644,
6453 		.proc_handler	= proc_dointvec,
6454 	},
6455 	{
6456 		.procname	= "temp_valid_lft",
6457 		.data		= &ipv6_devconf.temp_valid_lft,
6458 		.maxlen		= sizeof(int),
6459 		.mode		= 0644,
6460 		.proc_handler	= proc_dointvec,
6461 	},
6462 	{
6463 		.procname	= "temp_prefered_lft",
6464 		.data		= &ipv6_devconf.temp_prefered_lft,
6465 		.maxlen		= sizeof(int),
6466 		.mode		= 0644,
6467 		.proc_handler	= proc_dointvec,
6468 	},
6469 	{
6470 		.procname	= "regen_max_retry",
6471 		.data		= &ipv6_devconf.regen_max_retry,
6472 		.maxlen		= sizeof(int),
6473 		.mode		= 0644,
6474 		.proc_handler	= proc_dointvec,
6475 	},
6476 	{
6477 		.procname	= "max_desync_factor",
6478 		.data		= &ipv6_devconf.max_desync_factor,
6479 		.maxlen		= sizeof(int),
6480 		.mode		= 0644,
6481 		.proc_handler	= proc_dointvec,
6482 	},
6483 	{
6484 		.procname	= "max_addresses",
6485 		.data		= &ipv6_devconf.max_addresses,
6486 		.maxlen		= sizeof(int),
6487 		.mode		= 0644,
6488 		.proc_handler	= proc_dointvec,
6489 	},
6490 	{
6491 		.procname	= "accept_ra_defrtr",
6492 		.data		= &ipv6_devconf.accept_ra_defrtr,
6493 		.maxlen		= sizeof(int),
6494 		.mode		= 0644,
6495 		.proc_handler	= proc_dointvec,
6496 	},
6497 	{
6498 		.procname	= "accept_ra_min_hop_limit",
6499 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6500 		.maxlen		= sizeof(int),
6501 		.mode		= 0644,
6502 		.proc_handler	= proc_dointvec,
6503 	},
6504 	{
6505 		.procname	= "accept_ra_pinfo",
6506 		.data		= &ipv6_devconf.accept_ra_pinfo,
6507 		.maxlen		= sizeof(int),
6508 		.mode		= 0644,
6509 		.proc_handler	= proc_dointvec,
6510 	},
6511 #ifdef CONFIG_IPV6_ROUTER_PREF
6512 	{
6513 		.procname	= "accept_ra_rtr_pref",
6514 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6515 		.maxlen		= sizeof(int),
6516 		.mode		= 0644,
6517 		.proc_handler	= proc_dointvec,
6518 	},
6519 	{
6520 		.procname	= "router_probe_interval",
6521 		.data		= &ipv6_devconf.rtr_probe_interval,
6522 		.maxlen		= sizeof(int),
6523 		.mode		= 0644,
6524 		.proc_handler	= proc_dointvec_jiffies,
6525 	},
6526 #ifdef CONFIG_IPV6_ROUTE_INFO
6527 	{
6528 		.procname	= "accept_ra_rt_info_min_plen",
6529 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6530 		.maxlen		= sizeof(int),
6531 		.mode		= 0644,
6532 		.proc_handler	= proc_dointvec,
6533 	},
6534 	{
6535 		.procname	= "accept_ra_rt_info_max_plen",
6536 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6537 		.maxlen		= sizeof(int),
6538 		.mode		= 0644,
6539 		.proc_handler	= proc_dointvec,
6540 	},
6541 #endif
6542 #endif
6543 	{
6544 		.procname	= "proxy_ndp",
6545 		.data		= &ipv6_devconf.proxy_ndp,
6546 		.maxlen		= sizeof(int),
6547 		.mode		= 0644,
6548 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6549 	},
6550 	{
6551 		.procname	= "accept_source_route",
6552 		.data		= &ipv6_devconf.accept_source_route,
6553 		.maxlen		= sizeof(int),
6554 		.mode		= 0644,
6555 		.proc_handler	= proc_dointvec,
6556 	},
6557 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6558 	{
6559 		.procname	= "optimistic_dad",
6560 		.data		= &ipv6_devconf.optimistic_dad,
6561 		.maxlen		= sizeof(int),
6562 		.mode		= 0644,
6563 		.proc_handler   = proc_dointvec,
6564 	},
6565 	{
6566 		.procname	= "use_optimistic",
6567 		.data		= &ipv6_devconf.use_optimistic,
6568 		.maxlen		= sizeof(int),
6569 		.mode		= 0644,
6570 		.proc_handler	= proc_dointvec,
6571 	},
6572 #endif
6573 #ifdef CONFIG_IPV6_MROUTE
6574 	{
6575 		.procname	= "mc_forwarding",
6576 		.data		= &ipv6_devconf.mc_forwarding,
6577 		.maxlen		= sizeof(int),
6578 		.mode		= 0444,
6579 		.proc_handler	= proc_dointvec,
6580 	},
6581 #endif
6582 	{
6583 		.procname	= "disable_ipv6",
6584 		.data		= &ipv6_devconf.disable_ipv6,
6585 		.maxlen		= sizeof(int),
6586 		.mode		= 0644,
6587 		.proc_handler	= addrconf_sysctl_disable,
6588 	},
6589 	{
6590 		.procname	= "accept_dad",
6591 		.data		= &ipv6_devconf.accept_dad,
6592 		.maxlen		= sizeof(int),
6593 		.mode		= 0644,
6594 		.proc_handler	= proc_dointvec,
6595 	},
6596 	{
6597 		.procname	= "force_tllao",
6598 		.data		= &ipv6_devconf.force_tllao,
6599 		.maxlen		= sizeof(int),
6600 		.mode		= 0644,
6601 		.proc_handler	= proc_dointvec
6602 	},
6603 	{
6604 		.procname	= "ndisc_notify",
6605 		.data		= &ipv6_devconf.ndisc_notify,
6606 		.maxlen		= sizeof(int),
6607 		.mode		= 0644,
6608 		.proc_handler	= proc_dointvec
6609 	},
6610 	{
6611 		.procname	= "suppress_frag_ndisc",
6612 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6613 		.maxlen		= sizeof(int),
6614 		.mode		= 0644,
6615 		.proc_handler	= proc_dointvec
6616 	},
6617 	{
6618 		.procname	= "accept_ra_from_local",
6619 		.data		= &ipv6_devconf.accept_ra_from_local,
6620 		.maxlen		= sizeof(int),
6621 		.mode		= 0644,
6622 		.proc_handler	= proc_dointvec,
6623 	},
6624 	{
6625 		.procname	= "accept_ra_mtu",
6626 		.data		= &ipv6_devconf.accept_ra_mtu,
6627 		.maxlen		= sizeof(int),
6628 		.mode		= 0644,
6629 		.proc_handler	= proc_dointvec,
6630 	},
6631 	{
6632 		.procname	= "stable_secret",
6633 		.data		= &ipv6_devconf.stable_secret,
6634 		.maxlen		= IPV6_MAX_STRLEN,
6635 		.mode		= 0600,
6636 		.proc_handler	= addrconf_sysctl_stable_secret,
6637 	},
6638 	{
6639 		.procname	= "use_oif_addrs_only",
6640 		.data		= &ipv6_devconf.use_oif_addrs_only,
6641 		.maxlen		= sizeof(int),
6642 		.mode		= 0644,
6643 		.proc_handler	= proc_dointvec,
6644 	},
6645 	{
6646 		.procname	= "ignore_routes_with_linkdown",
6647 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6648 		.maxlen		= sizeof(int),
6649 		.mode		= 0644,
6650 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6651 	},
6652 	{
6653 		.procname	= "drop_unicast_in_l2_multicast",
6654 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6655 		.maxlen		= sizeof(int),
6656 		.mode		= 0644,
6657 		.proc_handler	= proc_dointvec,
6658 	},
6659 	{
6660 		.procname	= "drop_unsolicited_na",
6661 		.data		= &ipv6_devconf.drop_unsolicited_na,
6662 		.maxlen		= sizeof(int),
6663 		.mode		= 0644,
6664 		.proc_handler	= proc_dointvec,
6665 	},
6666 	{
6667 		.procname	= "keep_addr_on_down",
6668 		.data		= &ipv6_devconf.keep_addr_on_down,
6669 		.maxlen		= sizeof(int),
6670 		.mode		= 0644,
6671 		.proc_handler	= proc_dointvec,
6672 
6673 	},
6674 	{
6675 		.procname	= "seg6_enabled",
6676 		.data		= &ipv6_devconf.seg6_enabled,
6677 		.maxlen		= sizeof(int),
6678 		.mode		= 0644,
6679 		.proc_handler	= proc_dointvec,
6680 	},
6681 #ifdef CONFIG_IPV6_SEG6_HMAC
6682 	{
6683 		.procname	= "seg6_require_hmac",
6684 		.data		= &ipv6_devconf.seg6_require_hmac,
6685 		.maxlen		= sizeof(int),
6686 		.mode		= 0644,
6687 		.proc_handler	= proc_dointvec,
6688 	},
6689 #endif
6690 	{
6691 		.procname       = "enhanced_dad",
6692 		.data           = &ipv6_devconf.enhanced_dad,
6693 		.maxlen         = sizeof(int),
6694 		.mode           = 0644,
6695 		.proc_handler   = proc_dointvec,
6696 	},
6697 	{
6698 		.procname		= "addr_gen_mode",
6699 		.data			= &ipv6_devconf.addr_gen_mode,
6700 		.maxlen			= sizeof(int),
6701 		.mode			= 0644,
6702 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6703 	},
6704 	{
6705 		.procname       = "disable_policy",
6706 		.data           = &ipv6_devconf.disable_policy,
6707 		.maxlen         = sizeof(int),
6708 		.mode           = 0644,
6709 		.proc_handler   = addrconf_sysctl_disable_policy,
6710 	},
6711 	{
6712 		.procname	= "ndisc_tclass",
6713 		.data		= &ipv6_devconf.ndisc_tclass,
6714 		.maxlen		= sizeof(int),
6715 		.mode		= 0644,
6716 		.proc_handler	= proc_dointvec_minmax,
6717 		.extra1		= (void *)&zero,
6718 		.extra2		= (void *)&two_five_five,
6719 	},
6720 	{
6721 		/* sentinel */
6722 	}
6723 };
6724 
6725 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6726 		struct inet6_dev *idev, struct ipv6_devconf *p)
6727 {
6728 	int i, ifindex;
6729 	struct ctl_table *table;
6730 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6731 
6732 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6733 	if (!table)
6734 		goto out;
6735 
6736 	for (i = 0; table[i].data; i++) {
6737 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6738 		/* If one of these is already set, then it is not safe to
6739 		 * overwrite either of them: this makes proc_dointvec_minmax
6740 		 * usable.
6741 		 */
6742 		if (!table[i].extra1 && !table[i].extra2) {
6743 			table[i].extra1 = idev; /* embedded; no ref */
6744 			table[i].extra2 = net;
6745 		}
6746 	}
6747 
6748 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6749 
6750 	p->sysctl_header = register_net_sysctl(net, path, table);
6751 	if (!p->sysctl_header)
6752 		goto free;
6753 
6754 	if (!strcmp(dev_name, "all"))
6755 		ifindex = NETCONFA_IFINDEX_ALL;
6756 	else if (!strcmp(dev_name, "default"))
6757 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6758 	else
6759 		ifindex = idev->dev->ifindex;
6760 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6761 				     ifindex, p);
6762 	return 0;
6763 
6764 free:
6765 	kfree(table);
6766 out:
6767 	return -ENOBUFS;
6768 }
6769 
6770 static void __addrconf_sysctl_unregister(struct net *net,
6771 					 struct ipv6_devconf *p, int ifindex)
6772 {
6773 	struct ctl_table *table;
6774 
6775 	if (!p->sysctl_header)
6776 		return;
6777 
6778 	table = p->sysctl_header->ctl_table_arg;
6779 	unregister_net_sysctl_table(p->sysctl_header);
6780 	p->sysctl_header = NULL;
6781 	kfree(table);
6782 
6783 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6784 }
6785 
6786 static int addrconf_sysctl_register(struct inet6_dev *idev)
6787 {
6788 	int err;
6789 
6790 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6791 		return -EINVAL;
6792 
6793 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6794 				    &ndisc_ifinfo_sysctl_change);
6795 	if (err)
6796 		return err;
6797 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6798 					 idev, &idev->cnf);
6799 	if (err)
6800 		neigh_sysctl_unregister(idev->nd_parms);
6801 
6802 	return err;
6803 }
6804 
6805 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6806 {
6807 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6808 				     idev->dev->ifindex);
6809 	neigh_sysctl_unregister(idev->nd_parms);
6810 }
6811 
6812 
6813 #endif
6814 
6815 static int __net_init addrconf_init_net(struct net *net)
6816 {
6817 	int err = -ENOMEM;
6818 	struct ipv6_devconf *all, *dflt;
6819 
6820 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6821 	if (!all)
6822 		goto err_alloc_all;
6823 
6824 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6825 	if (!dflt)
6826 		goto err_alloc_dflt;
6827 
6828 	/* these will be inherited by all namespaces */
6829 	dflt->autoconf = ipv6_defaults.autoconf;
6830 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6831 
6832 	dflt->stable_secret.initialized = false;
6833 	all->stable_secret.initialized = false;
6834 
6835 	net->ipv6.devconf_all = all;
6836 	net->ipv6.devconf_dflt = dflt;
6837 
6838 #ifdef CONFIG_SYSCTL
6839 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6840 	if (err < 0)
6841 		goto err_reg_all;
6842 
6843 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6844 	if (err < 0)
6845 		goto err_reg_dflt;
6846 #endif
6847 	return 0;
6848 
6849 #ifdef CONFIG_SYSCTL
6850 err_reg_dflt:
6851 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6852 err_reg_all:
6853 	kfree(dflt);
6854 #endif
6855 err_alloc_dflt:
6856 	kfree(all);
6857 err_alloc_all:
6858 	return err;
6859 }
6860 
6861 static void __net_exit addrconf_exit_net(struct net *net)
6862 {
6863 #ifdef CONFIG_SYSCTL
6864 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6865 				     NETCONFA_IFINDEX_DEFAULT);
6866 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6867 				     NETCONFA_IFINDEX_ALL);
6868 #endif
6869 	kfree(net->ipv6.devconf_dflt);
6870 	kfree(net->ipv6.devconf_all);
6871 }
6872 
6873 static struct pernet_operations addrconf_ops = {
6874 	.init = addrconf_init_net,
6875 	.exit = addrconf_exit_net,
6876 };
6877 
6878 static struct rtnl_af_ops inet6_ops __read_mostly = {
6879 	.family		  = AF_INET6,
6880 	.fill_link_af	  = inet6_fill_link_af,
6881 	.get_link_af_size = inet6_get_link_af_size,
6882 	.validate_link_af = inet6_validate_link_af,
6883 	.set_link_af	  = inet6_set_link_af,
6884 };
6885 
6886 /*
6887  *	Init / cleanup code
6888  */
6889 
6890 int __init addrconf_init(void)
6891 {
6892 	struct inet6_dev *idev;
6893 	int i, err;
6894 
6895 	err = ipv6_addr_label_init();
6896 	if (err < 0) {
6897 		pr_crit("%s: cannot initialize default policy table: %d\n",
6898 			__func__, err);
6899 		goto out;
6900 	}
6901 
6902 	err = register_pernet_subsys(&addrconf_ops);
6903 	if (err < 0)
6904 		goto out_addrlabel;
6905 
6906 	addrconf_wq = create_workqueue("ipv6_addrconf");
6907 	if (!addrconf_wq) {
6908 		err = -ENOMEM;
6909 		goto out_nowq;
6910 	}
6911 
6912 	/* The addrconf netdev notifier requires that loopback_dev
6913 	 * has it's ipv6 private information allocated and setup
6914 	 * before it can bring up and give link-local addresses
6915 	 * to other devices which are up.
6916 	 *
6917 	 * Unfortunately, loopback_dev is not necessarily the first
6918 	 * entry in the global dev_base list of net devices.  In fact,
6919 	 * it is likely to be the very last entry on that list.
6920 	 * So this causes the notifier registry below to try and
6921 	 * give link-local addresses to all devices besides loopback_dev
6922 	 * first, then loopback_dev, which cases all the non-loopback_dev
6923 	 * devices to fail to get a link-local address.
6924 	 *
6925 	 * So, as a temporary fix, allocate the ipv6 structure for
6926 	 * loopback_dev first by hand.
6927 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6928 	 * device and it being up should be removed.
6929 	 */
6930 	rtnl_lock();
6931 	idev = ipv6_add_dev(init_net.loopback_dev);
6932 	rtnl_unlock();
6933 	if (IS_ERR(idev)) {
6934 		err = PTR_ERR(idev);
6935 		goto errlo;
6936 	}
6937 
6938 	ip6_route_init_special_entries();
6939 
6940 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6941 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6942 
6943 	register_netdevice_notifier(&ipv6_dev_notf);
6944 
6945 	addrconf_verify();
6946 
6947 	rtnl_af_register(&inet6_ops);
6948 
6949 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
6950 				   NULL, inet6_dump_ifinfo, 0);
6951 	if (err < 0)
6952 		goto errout;
6953 
6954 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
6955 				   inet6_rtm_newaddr, NULL, 0);
6956 	if (err < 0)
6957 		goto errout;
6958 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
6959 				   inet6_rtm_deladdr, NULL, 0);
6960 	if (err < 0)
6961 		goto errout;
6962 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
6963 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
6964 				   RTNL_FLAG_DOIT_UNLOCKED);
6965 	if (err < 0)
6966 		goto errout;
6967 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
6968 				   NULL, inet6_dump_ifmcaddr, 0);
6969 	if (err < 0)
6970 		goto errout;
6971 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
6972 				   NULL, inet6_dump_ifacaddr, 0);
6973 	if (err < 0)
6974 		goto errout;
6975 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
6976 				   inet6_netconf_get_devconf,
6977 				   inet6_netconf_dump_devconf,
6978 				   RTNL_FLAG_DOIT_UNLOCKED);
6979 	if (err < 0)
6980 		goto errout;
6981 	err = ipv6_addr_label_rtnl_register();
6982 	if (err < 0)
6983 		goto errout;
6984 
6985 	return 0;
6986 errout:
6987 	rtnl_unregister_all(PF_INET6);
6988 	rtnl_af_unregister(&inet6_ops);
6989 	unregister_netdevice_notifier(&ipv6_dev_notf);
6990 errlo:
6991 	destroy_workqueue(addrconf_wq);
6992 out_nowq:
6993 	unregister_pernet_subsys(&addrconf_ops);
6994 out_addrlabel:
6995 	ipv6_addr_label_cleanup();
6996 out:
6997 	return err;
6998 }
6999 
7000 void addrconf_cleanup(void)
7001 {
7002 	struct net_device *dev;
7003 	int i;
7004 
7005 	unregister_netdevice_notifier(&ipv6_dev_notf);
7006 	unregister_pernet_subsys(&addrconf_ops);
7007 	ipv6_addr_label_cleanup();
7008 
7009 	rtnl_af_unregister(&inet6_ops);
7010 
7011 	rtnl_lock();
7012 
7013 	/* clean dev list */
7014 	for_each_netdev(&init_net, dev) {
7015 		if (__in6_dev_get(dev) == NULL)
7016 			continue;
7017 		addrconf_ifdown(dev, 1);
7018 	}
7019 	addrconf_ifdown(init_net.loopback_dev, 2);
7020 
7021 	/*
7022 	 *	Check hash table.
7023 	 */
7024 	spin_lock_bh(&addrconf_hash_lock);
7025 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7026 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7027 	spin_unlock_bh(&addrconf_hash_lock);
7028 	cancel_delayed_work(&addr_chk_work);
7029 	rtnl_unlock();
7030 
7031 	destroy_workqueue(addrconf_wq);
7032 }
7033