xref: /openbmc/linux/net/ipv6/addrconf.c (revision cb1aaebe)
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 						  bool no_gw);
178 
179 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
180 static void addrconf_dad_work(struct work_struct *w);
181 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
182 				   bool send_na);
183 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
184 static void addrconf_rs_timer(struct timer_list *t);
185 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
187 
188 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
189 				struct prefix_info *pinfo);
190 
191 static struct ipv6_devconf ipv6_devconf __read_mostly = {
192 	.forwarding		= 0,
193 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
194 	.mtu6			= IPV6_MIN_MTU,
195 	.accept_ra		= 1,
196 	.accept_redirects	= 1,
197 	.autoconf		= 1,
198 	.force_mld_version	= 0,
199 	.mldv1_unsolicited_report_interval = 10 * HZ,
200 	.mldv2_unsolicited_report_interval = HZ,
201 	.dad_transmits		= 1,
202 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
203 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
204 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
205 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
206 	.use_tempaddr		= 0,
207 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
208 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
209 	.regen_max_retry	= REGEN_MAX_RETRY,
210 	.max_desync_factor	= MAX_DESYNC_FACTOR,
211 	.max_addresses		= IPV6_MAX_ADDRESSES,
212 	.accept_ra_defrtr	= 1,
213 	.accept_ra_from_local	= 0,
214 	.accept_ra_min_hop_limit= 1,
215 	.accept_ra_pinfo	= 1,
216 #ifdef CONFIG_IPV6_ROUTER_PREF
217 	.accept_ra_rtr_pref	= 1,
218 	.rtr_probe_interval	= 60 * HZ,
219 #ifdef CONFIG_IPV6_ROUTE_INFO
220 	.accept_ra_rt_info_min_plen = 0,
221 	.accept_ra_rt_info_max_plen = 0,
222 #endif
223 #endif
224 	.proxy_ndp		= 0,
225 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
226 	.disable_ipv6		= 0,
227 	.accept_dad		= 0,
228 	.suppress_frag_ndisc	= 1,
229 	.accept_ra_mtu		= 1,
230 	.stable_secret		= {
231 		.initialized = false,
232 	},
233 	.use_oif_addrs_only	= 0,
234 	.ignore_routes_with_linkdown = 0,
235 	.keep_addr_on_down	= 0,
236 	.seg6_enabled		= 0,
237 #ifdef CONFIG_IPV6_SEG6_HMAC
238 	.seg6_require_hmac	= 0,
239 #endif
240 	.enhanced_dad           = 1,
241 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
242 	.disable_policy		= 0,
243 };
244 
245 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
246 	.forwarding		= 0,
247 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
248 	.mtu6			= IPV6_MIN_MTU,
249 	.accept_ra		= 1,
250 	.accept_redirects	= 1,
251 	.autoconf		= 1,
252 	.force_mld_version	= 0,
253 	.mldv1_unsolicited_report_interval = 10 * HZ,
254 	.mldv2_unsolicited_report_interval = HZ,
255 	.dad_transmits		= 1,
256 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
257 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
258 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
259 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
260 	.use_tempaddr		= 0,
261 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
262 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
263 	.regen_max_retry	= REGEN_MAX_RETRY,
264 	.max_desync_factor	= MAX_DESYNC_FACTOR,
265 	.max_addresses		= IPV6_MAX_ADDRESSES,
266 	.accept_ra_defrtr	= 1,
267 	.accept_ra_from_local	= 0,
268 	.accept_ra_min_hop_limit= 1,
269 	.accept_ra_pinfo	= 1,
270 #ifdef CONFIG_IPV6_ROUTER_PREF
271 	.accept_ra_rtr_pref	= 1,
272 	.rtr_probe_interval	= 60 * HZ,
273 #ifdef CONFIG_IPV6_ROUTE_INFO
274 	.accept_ra_rt_info_min_plen = 0,
275 	.accept_ra_rt_info_max_plen = 0,
276 #endif
277 #endif
278 	.proxy_ndp		= 0,
279 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
280 	.disable_ipv6		= 0,
281 	.accept_dad		= 1,
282 	.suppress_frag_ndisc	= 1,
283 	.accept_ra_mtu		= 1,
284 	.stable_secret		= {
285 		.initialized = false,
286 	},
287 	.use_oif_addrs_only	= 0,
288 	.ignore_routes_with_linkdown = 0,
289 	.keep_addr_on_down	= 0,
290 	.seg6_enabled		= 0,
291 #ifdef CONFIG_IPV6_SEG6_HMAC
292 	.seg6_require_hmac	= 0,
293 #endif
294 	.enhanced_dad           = 1,
295 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
296 	.disable_policy		= 0,
297 };
298 
299 /* Check if link is ready: is it up and is a valid qdisc available */
300 static inline bool addrconf_link_ready(const struct net_device *dev)
301 {
302 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
303 }
304 
305 static void addrconf_del_rs_timer(struct inet6_dev *idev)
306 {
307 	if (del_timer(&idev->rs_timer))
308 		__in6_dev_put(idev);
309 }
310 
311 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
312 {
313 	if (cancel_delayed_work(&ifp->dad_work))
314 		__in6_ifa_put(ifp);
315 }
316 
317 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
318 				  unsigned long when)
319 {
320 	if (!timer_pending(&idev->rs_timer))
321 		in6_dev_hold(idev);
322 	mod_timer(&idev->rs_timer, jiffies + when);
323 }
324 
325 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
326 				   unsigned long delay)
327 {
328 	in6_ifa_hold(ifp);
329 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
330 		in6_ifa_put(ifp);
331 }
332 
333 static int snmp6_alloc_dev(struct inet6_dev *idev)
334 {
335 	int i;
336 
337 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
338 	if (!idev->stats.ipv6)
339 		goto err_ip;
340 
341 	for_each_possible_cpu(i) {
342 		struct ipstats_mib *addrconf_stats;
343 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
344 		u64_stats_init(&addrconf_stats->syncp);
345 	}
346 
347 
348 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
349 					GFP_KERNEL);
350 	if (!idev->stats.icmpv6dev)
351 		goto err_icmp;
352 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
353 					   GFP_KERNEL);
354 	if (!idev->stats.icmpv6msgdev)
355 		goto err_icmpmsg;
356 
357 	return 0;
358 
359 err_icmpmsg:
360 	kfree(idev->stats.icmpv6dev);
361 err_icmp:
362 	free_percpu(idev->stats.ipv6);
363 err_ip:
364 	return -ENOMEM;
365 }
366 
367 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
368 {
369 	struct inet6_dev *ndev;
370 	int err = -ENOMEM;
371 
372 	ASSERT_RTNL();
373 
374 	if (dev->mtu < IPV6_MIN_MTU)
375 		return ERR_PTR(-EINVAL);
376 
377 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
378 	if (!ndev)
379 		return ERR_PTR(err);
380 
381 	rwlock_init(&ndev->lock);
382 	ndev->dev = dev;
383 	INIT_LIST_HEAD(&ndev->addr_list);
384 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
385 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
386 
387 	if (ndev->cnf.stable_secret.initialized)
388 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
389 
390 	ndev->cnf.mtu6 = dev->mtu;
391 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
392 	if (!ndev->nd_parms) {
393 		kfree(ndev);
394 		return ERR_PTR(err);
395 	}
396 	if (ndev->cnf.forwarding)
397 		dev_disable_lro(dev);
398 	/* We refer to the device */
399 	dev_hold(dev);
400 
401 	if (snmp6_alloc_dev(ndev) < 0) {
402 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
403 			   __func__);
404 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
405 		dev_put(dev);
406 		kfree(ndev);
407 		return ERR_PTR(err);
408 	}
409 
410 	if (snmp6_register_dev(ndev) < 0) {
411 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
412 			   __func__, dev->name);
413 		goto err_release;
414 	}
415 
416 	/* One reference from device. */
417 	refcount_set(&ndev->refcnt, 1);
418 
419 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
420 		ndev->cnf.accept_dad = -1;
421 
422 #if IS_ENABLED(CONFIG_IPV6_SIT)
423 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
424 		pr_info("%s: Disabled Multicast RS\n", dev->name);
425 		ndev->cnf.rtr_solicits = 0;
426 	}
427 #endif
428 
429 	INIT_LIST_HEAD(&ndev->tempaddr_list);
430 	ndev->desync_factor = U32_MAX;
431 	if ((dev->flags&IFF_LOOPBACK) ||
432 	    dev->type == ARPHRD_TUNNEL ||
433 	    dev->type == ARPHRD_TUNNEL6 ||
434 	    dev->type == ARPHRD_SIT ||
435 	    dev->type == ARPHRD_NONE) {
436 		ndev->cnf.use_tempaddr = -1;
437 	} else
438 		ipv6_regen_rndid(ndev);
439 
440 	ndev->token = in6addr_any;
441 
442 	if (netif_running(dev) && addrconf_link_ready(dev))
443 		ndev->if_flags |= IF_READY;
444 
445 	ipv6_mc_init_dev(ndev);
446 	ndev->tstamp = jiffies;
447 	err = addrconf_sysctl_register(ndev);
448 	if (err) {
449 		ipv6_mc_destroy_dev(ndev);
450 		snmp6_unregister_dev(ndev);
451 		goto err_release;
452 	}
453 	/* protected by rtnl_lock */
454 	rcu_assign_pointer(dev->ip6_ptr, ndev);
455 
456 	/* Join interface-local all-node multicast group */
457 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
458 
459 	/* Join all-node multicast group */
460 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
461 
462 	/* Join all-router multicast group if forwarding is set */
463 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
464 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
465 
466 	return ndev;
467 
468 err_release:
469 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
470 	ndev->dead = 1;
471 	in6_dev_finish_destroy(ndev);
472 	return ERR_PTR(err);
473 }
474 
475 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
476 {
477 	struct inet6_dev *idev;
478 
479 	ASSERT_RTNL();
480 
481 	idev = __in6_dev_get(dev);
482 	if (!idev) {
483 		idev = ipv6_add_dev(dev);
484 		if (IS_ERR(idev))
485 			return NULL;
486 	}
487 
488 	if (dev->flags&IFF_UP)
489 		ipv6_mc_up(idev);
490 	return idev;
491 }
492 
493 static int inet6_netconf_msgsize_devconf(int type)
494 {
495 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
496 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
497 	bool all = false;
498 
499 	if (type == NETCONFA_ALL)
500 		all = true;
501 
502 	if (all || type == NETCONFA_FORWARDING)
503 		size += nla_total_size(4);
504 #ifdef CONFIG_IPV6_MROUTE
505 	if (all || type == NETCONFA_MC_FORWARDING)
506 		size += nla_total_size(4);
507 #endif
508 	if (all || type == NETCONFA_PROXY_NEIGH)
509 		size += nla_total_size(4);
510 
511 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
512 		size += nla_total_size(4);
513 
514 	return size;
515 }
516 
517 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
518 				      struct ipv6_devconf *devconf, u32 portid,
519 				      u32 seq, int event, unsigned int flags,
520 				      int type)
521 {
522 	struct nlmsghdr  *nlh;
523 	struct netconfmsg *ncm;
524 	bool all = false;
525 
526 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
527 			flags);
528 	if (!nlh)
529 		return -EMSGSIZE;
530 
531 	if (type == NETCONFA_ALL)
532 		all = true;
533 
534 	ncm = nlmsg_data(nlh);
535 	ncm->ncm_family = AF_INET6;
536 
537 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
538 		goto nla_put_failure;
539 
540 	if (!devconf)
541 		goto out;
542 
543 	if ((all || type == NETCONFA_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
545 		goto nla_put_failure;
546 #ifdef CONFIG_IPV6_MROUTE
547 	if ((all || type == NETCONFA_MC_FORWARDING) &&
548 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
549 			devconf->mc_forwarding) < 0)
550 		goto nla_put_failure;
551 #endif
552 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
553 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
554 		goto nla_put_failure;
555 
556 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
557 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
558 			devconf->ignore_routes_with_linkdown) < 0)
559 		goto nla_put_failure;
560 
561 out:
562 	nlmsg_end(skb, nlh);
563 	return 0;
564 
565 nla_put_failure:
566 	nlmsg_cancel(skb, nlh);
567 	return -EMSGSIZE;
568 }
569 
570 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
571 				  int ifindex, struct ipv6_devconf *devconf)
572 {
573 	struct sk_buff *skb;
574 	int err = -ENOBUFS;
575 
576 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
577 	if (!skb)
578 		goto errout;
579 
580 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
581 					 event, 0, type);
582 	if (err < 0) {
583 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
584 		WARN_ON(err == -EMSGSIZE);
585 		kfree_skb(skb);
586 		goto errout;
587 	}
588 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
589 	return;
590 errout:
591 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
592 }
593 
594 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
595 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
596 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
597 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
598 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
599 };
600 
601 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
602 				       const struct nlmsghdr *nlh,
603 				       struct nlattr **tb,
604 				       struct netlink_ext_ack *extack)
605 {
606 	int i, err;
607 
608 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
609 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
610 		return -EINVAL;
611 	}
612 
613 	if (!netlink_strict_get_check(skb))
614 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
615 					      tb, NETCONFA_MAX,
616 					      devconf_ipv6_policy, extack);
617 
618 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
619 					    tb, NETCONFA_MAX,
620 					    devconf_ipv6_policy, extack);
621 	if (err)
622 		return err;
623 
624 	for (i = 0; i <= NETCONFA_MAX; i++) {
625 		if (!tb[i])
626 			continue;
627 
628 		switch (i) {
629 		case NETCONFA_IFINDEX:
630 			break;
631 		default:
632 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
633 			return -EINVAL;
634 		}
635 	}
636 
637 	return 0;
638 }
639 
640 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
641 				     struct nlmsghdr *nlh,
642 				     struct netlink_ext_ack *extack)
643 {
644 	struct net *net = sock_net(in_skb->sk);
645 	struct nlattr *tb[NETCONFA_MAX+1];
646 	struct inet6_dev *in6_dev = NULL;
647 	struct net_device *dev = NULL;
648 	struct sk_buff *skb;
649 	struct ipv6_devconf *devconf;
650 	int ifindex;
651 	int err;
652 
653 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
654 	if (err < 0)
655 		return err;
656 
657 	if (!tb[NETCONFA_IFINDEX])
658 		return -EINVAL;
659 
660 	err = -EINVAL;
661 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
662 	switch (ifindex) {
663 	case NETCONFA_IFINDEX_ALL:
664 		devconf = net->ipv6.devconf_all;
665 		break;
666 	case NETCONFA_IFINDEX_DEFAULT:
667 		devconf = net->ipv6.devconf_dflt;
668 		break;
669 	default:
670 		dev = dev_get_by_index(net, ifindex);
671 		if (!dev)
672 			return -EINVAL;
673 		in6_dev = in6_dev_get(dev);
674 		if (!in6_dev)
675 			goto errout;
676 		devconf = &in6_dev->cnf;
677 		break;
678 	}
679 
680 	err = -ENOBUFS;
681 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
682 	if (!skb)
683 		goto errout;
684 
685 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
686 					 NETLINK_CB(in_skb).portid,
687 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
688 					 NETCONFA_ALL);
689 	if (err < 0) {
690 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
691 		WARN_ON(err == -EMSGSIZE);
692 		kfree_skb(skb);
693 		goto errout;
694 	}
695 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
696 errout:
697 	if (in6_dev)
698 		in6_dev_put(in6_dev);
699 	if (dev)
700 		dev_put(dev);
701 	return err;
702 }
703 
704 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
705 				      struct netlink_callback *cb)
706 {
707 	const struct nlmsghdr *nlh = cb->nlh;
708 	struct net *net = sock_net(skb->sk);
709 	int h, s_h;
710 	int idx, s_idx;
711 	struct net_device *dev;
712 	struct inet6_dev *idev;
713 	struct hlist_head *head;
714 
715 	if (cb->strict_check) {
716 		struct netlink_ext_ack *extack = cb->extack;
717 		struct netconfmsg *ncm;
718 
719 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
720 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
721 			return -EINVAL;
722 		}
723 
724 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
725 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
726 			return -EINVAL;
727 		}
728 	}
729 
730 	s_h = cb->args[0];
731 	s_idx = idx = cb->args[1];
732 
733 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
734 		idx = 0;
735 		head = &net->dev_index_head[h];
736 		rcu_read_lock();
737 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
738 			  net->dev_base_seq;
739 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
740 			if (idx < s_idx)
741 				goto cont;
742 			idev = __in6_dev_get(dev);
743 			if (!idev)
744 				goto cont;
745 
746 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
747 						       &idev->cnf,
748 						       NETLINK_CB(cb->skb).portid,
749 						       nlh->nlmsg_seq,
750 						       RTM_NEWNETCONF,
751 						       NLM_F_MULTI,
752 						       NETCONFA_ALL) < 0) {
753 				rcu_read_unlock();
754 				goto done;
755 			}
756 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
757 cont:
758 			idx++;
759 		}
760 		rcu_read_unlock();
761 	}
762 	if (h == NETDEV_HASHENTRIES) {
763 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
764 					       net->ipv6.devconf_all,
765 					       NETLINK_CB(cb->skb).portid,
766 					       nlh->nlmsg_seq,
767 					       RTM_NEWNETCONF, NLM_F_MULTI,
768 					       NETCONFA_ALL) < 0)
769 			goto done;
770 		else
771 			h++;
772 	}
773 	if (h == NETDEV_HASHENTRIES + 1) {
774 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
775 					       net->ipv6.devconf_dflt,
776 					       NETLINK_CB(cb->skb).portid,
777 					       nlh->nlmsg_seq,
778 					       RTM_NEWNETCONF, NLM_F_MULTI,
779 					       NETCONFA_ALL) < 0)
780 			goto done;
781 		else
782 			h++;
783 	}
784 done:
785 	cb->args[0] = h;
786 	cb->args[1] = idx;
787 
788 	return skb->len;
789 }
790 
791 #ifdef CONFIG_SYSCTL
792 static void dev_forward_change(struct inet6_dev *idev)
793 {
794 	struct net_device *dev;
795 	struct inet6_ifaddr *ifa;
796 
797 	if (!idev)
798 		return;
799 	dev = idev->dev;
800 	if (idev->cnf.forwarding)
801 		dev_disable_lro(dev);
802 	if (dev->flags & IFF_MULTICAST) {
803 		if (idev->cnf.forwarding) {
804 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
805 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
806 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
807 		} else {
808 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
809 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
810 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
811 		}
812 	}
813 
814 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
815 		if (ifa->flags&IFA_F_TENTATIVE)
816 			continue;
817 		if (idev->cnf.forwarding)
818 			addrconf_join_anycast(ifa);
819 		else
820 			addrconf_leave_anycast(ifa);
821 	}
822 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
823 				     NETCONFA_FORWARDING,
824 				     dev->ifindex, &idev->cnf);
825 }
826 
827 
828 static void addrconf_forward_change(struct net *net, __s32 newf)
829 {
830 	struct net_device *dev;
831 	struct inet6_dev *idev;
832 
833 	for_each_netdev(net, dev) {
834 		idev = __in6_dev_get(dev);
835 		if (idev) {
836 			int changed = (!idev->cnf.forwarding) ^ (!newf);
837 			idev->cnf.forwarding = newf;
838 			if (changed)
839 				dev_forward_change(idev);
840 		}
841 	}
842 }
843 
844 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
845 {
846 	struct net *net;
847 	int old;
848 
849 	if (!rtnl_trylock())
850 		return restart_syscall();
851 
852 	net = (struct net *)table->extra2;
853 	old = *p;
854 	*p = newf;
855 
856 	if (p == &net->ipv6.devconf_dflt->forwarding) {
857 		if ((!newf) ^ (!old))
858 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
859 						     NETCONFA_FORWARDING,
860 						     NETCONFA_IFINDEX_DEFAULT,
861 						     net->ipv6.devconf_dflt);
862 		rtnl_unlock();
863 		return 0;
864 	}
865 
866 	if (p == &net->ipv6.devconf_all->forwarding) {
867 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
868 
869 		net->ipv6.devconf_dflt->forwarding = newf;
870 		if ((!newf) ^ (!old_dflt))
871 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
872 						     NETCONFA_FORWARDING,
873 						     NETCONFA_IFINDEX_DEFAULT,
874 						     net->ipv6.devconf_dflt);
875 
876 		addrconf_forward_change(net, newf);
877 		if ((!newf) ^ (!old))
878 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
879 						     NETCONFA_FORWARDING,
880 						     NETCONFA_IFINDEX_ALL,
881 						     net->ipv6.devconf_all);
882 	} else if ((!newf) ^ (!old))
883 		dev_forward_change((struct inet6_dev *)table->extra1);
884 	rtnl_unlock();
885 
886 	if (newf)
887 		rt6_purge_dflt_routers(net);
888 	return 1;
889 }
890 
891 static void addrconf_linkdown_change(struct net *net, __s32 newf)
892 {
893 	struct net_device *dev;
894 	struct inet6_dev *idev;
895 
896 	for_each_netdev(net, dev) {
897 		idev = __in6_dev_get(dev);
898 		if (idev) {
899 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
900 
901 			idev->cnf.ignore_routes_with_linkdown = newf;
902 			if (changed)
903 				inet6_netconf_notify_devconf(dev_net(dev),
904 							     RTM_NEWNETCONF,
905 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
906 							     dev->ifindex,
907 							     &idev->cnf);
908 		}
909 	}
910 }
911 
912 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
913 {
914 	struct net *net;
915 	int old;
916 
917 	if (!rtnl_trylock())
918 		return restart_syscall();
919 
920 	net = (struct net *)table->extra2;
921 	old = *p;
922 	*p = newf;
923 
924 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
925 		if ((!newf) ^ (!old))
926 			inet6_netconf_notify_devconf(net,
927 						     RTM_NEWNETCONF,
928 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
929 						     NETCONFA_IFINDEX_DEFAULT,
930 						     net->ipv6.devconf_dflt);
931 		rtnl_unlock();
932 		return 0;
933 	}
934 
935 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
936 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
937 		addrconf_linkdown_change(net, newf);
938 		if ((!newf) ^ (!old))
939 			inet6_netconf_notify_devconf(net,
940 						     RTM_NEWNETCONF,
941 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
942 						     NETCONFA_IFINDEX_ALL,
943 						     net->ipv6.devconf_all);
944 	}
945 	rtnl_unlock();
946 
947 	return 1;
948 }
949 
950 #endif
951 
952 /* Nobody refers to this ifaddr, destroy it */
953 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
954 {
955 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
956 
957 #ifdef NET_REFCNT_DEBUG
958 	pr_debug("%s\n", __func__);
959 #endif
960 
961 	in6_dev_put(ifp->idev);
962 
963 	if (cancel_delayed_work(&ifp->dad_work))
964 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
965 			  ifp);
966 
967 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
968 		pr_warn("Freeing alive inet6 address %p\n", ifp);
969 		return;
970 	}
971 
972 	kfree_rcu(ifp, rcu);
973 }
974 
975 static void
976 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
977 {
978 	struct list_head *p;
979 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
980 
981 	/*
982 	 * Each device address list is sorted in order of scope -
983 	 * global before linklocal.
984 	 */
985 	list_for_each(p, &idev->addr_list) {
986 		struct inet6_ifaddr *ifa
987 			= list_entry(p, struct inet6_ifaddr, if_list);
988 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
989 			break;
990 	}
991 
992 	list_add_tail_rcu(&ifp->if_list, p);
993 }
994 
995 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
996 {
997 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
998 
999 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1000 }
1001 
1002 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1003 			       struct net_device *dev, unsigned int hash)
1004 {
1005 	struct inet6_ifaddr *ifp;
1006 
1007 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1008 		if (!net_eq(dev_net(ifp->idev->dev), net))
1009 			continue;
1010 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1011 			if (!dev || ifp->idev->dev == dev)
1012 				return true;
1013 		}
1014 	}
1015 	return false;
1016 }
1017 
1018 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1019 {
1020 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1021 	int err = 0;
1022 
1023 	spin_lock(&addrconf_hash_lock);
1024 
1025 	/* Ignore adding duplicate addresses on an interface */
1026 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1027 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1028 		err = -EEXIST;
1029 	} else {
1030 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1031 	}
1032 
1033 	spin_unlock(&addrconf_hash_lock);
1034 
1035 	return err;
1036 }
1037 
1038 /* On success it returns ifp with increased reference count */
1039 
1040 static struct inet6_ifaddr *
1041 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1042 	      bool can_block, struct netlink_ext_ack *extack)
1043 {
1044 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1045 	int addr_type = ipv6_addr_type(cfg->pfx);
1046 	struct net *net = dev_net(idev->dev);
1047 	struct inet6_ifaddr *ifa = NULL;
1048 	struct fib6_info *f6i = NULL;
1049 	int err = 0;
1050 
1051 	if (addr_type == IPV6_ADDR_ANY ||
1052 	    addr_type & IPV6_ADDR_MULTICAST ||
1053 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1054 	     !netif_is_l3_master(idev->dev) &&
1055 	     addr_type & IPV6_ADDR_LOOPBACK))
1056 		return ERR_PTR(-EADDRNOTAVAIL);
1057 
1058 	if (idev->dead) {
1059 		err = -ENODEV;			/*XXX*/
1060 		goto out;
1061 	}
1062 
1063 	if (idev->cnf.disable_ipv6) {
1064 		err = -EACCES;
1065 		goto out;
1066 	}
1067 
1068 	/* validator notifier needs to be blocking;
1069 	 * do not call in atomic context
1070 	 */
1071 	if (can_block) {
1072 		struct in6_validator_info i6vi = {
1073 			.i6vi_addr = *cfg->pfx,
1074 			.i6vi_dev = idev,
1075 			.extack = extack,
1076 		};
1077 
1078 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1079 		err = notifier_to_errno(err);
1080 		if (err < 0)
1081 			goto out;
1082 	}
1083 
1084 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1085 	if (!ifa) {
1086 		err = -ENOBUFS;
1087 		goto out;
1088 	}
1089 
1090 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1091 	if (IS_ERR(f6i)) {
1092 		err = PTR_ERR(f6i);
1093 		f6i = NULL;
1094 		goto out;
1095 	}
1096 
1097 	if (net->ipv6.devconf_all->disable_policy ||
1098 	    idev->cnf.disable_policy)
1099 		f6i->dst_nopolicy = true;
1100 
1101 	neigh_parms_data_state_setall(idev->nd_parms);
1102 
1103 	ifa->addr = *cfg->pfx;
1104 	if (cfg->peer_pfx)
1105 		ifa->peer_addr = *cfg->peer_pfx;
1106 
1107 	spin_lock_init(&ifa->lock);
1108 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1109 	INIT_HLIST_NODE(&ifa->addr_lst);
1110 	ifa->scope = cfg->scope;
1111 	ifa->prefix_len = cfg->plen;
1112 	ifa->rt_priority = cfg->rt_priority;
1113 	ifa->flags = cfg->ifa_flags;
1114 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1115 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1116 		ifa->flags |= IFA_F_TENTATIVE;
1117 	ifa->valid_lft = cfg->valid_lft;
1118 	ifa->prefered_lft = cfg->preferred_lft;
1119 	ifa->cstamp = ifa->tstamp = jiffies;
1120 	ifa->tokenized = false;
1121 
1122 	ifa->rt = f6i;
1123 
1124 	ifa->idev = idev;
1125 	in6_dev_hold(idev);
1126 
1127 	/* For caller */
1128 	refcount_set(&ifa->refcnt, 1);
1129 
1130 	rcu_read_lock_bh();
1131 
1132 	err = ipv6_add_addr_hash(idev->dev, ifa);
1133 	if (err < 0) {
1134 		rcu_read_unlock_bh();
1135 		goto out;
1136 	}
1137 
1138 	write_lock(&idev->lock);
1139 
1140 	/* Add to inet6_dev unicast addr list. */
1141 	ipv6_link_dev_addr(idev, ifa);
1142 
1143 	if (ifa->flags&IFA_F_TEMPORARY) {
1144 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1145 		in6_ifa_hold(ifa);
1146 	}
1147 
1148 	in6_ifa_hold(ifa);
1149 	write_unlock(&idev->lock);
1150 
1151 	rcu_read_unlock_bh();
1152 
1153 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1154 out:
1155 	if (unlikely(err < 0)) {
1156 		fib6_info_release(f6i);
1157 
1158 		if (ifa) {
1159 			if (ifa->idev)
1160 				in6_dev_put(ifa->idev);
1161 			kfree(ifa);
1162 		}
1163 		ifa = ERR_PTR(err);
1164 	}
1165 
1166 	return ifa;
1167 }
1168 
1169 enum cleanup_prefix_rt_t {
1170 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1171 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1172 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1173 };
1174 
1175 /*
1176  * Check, whether the prefix for ifp would still need a prefix route
1177  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1178  * constants.
1179  *
1180  * 1) we don't purge prefix if address was not permanent.
1181  *    prefix is managed by its own lifetime.
1182  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1183  * 3) if there are no addresses, delete prefix.
1184  * 4) if there are still other permanent address(es),
1185  *    corresponding prefix is still permanent.
1186  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1187  *    don't purge the prefix, assume user space is managing it.
1188  * 6) otherwise, update prefix lifetime to the
1189  *    longest valid lifetime among the corresponding
1190  *    addresses on the device.
1191  *    Note: subsequent RA will update lifetime.
1192  **/
1193 static enum cleanup_prefix_rt_t
1194 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1195 {
1196 	struct inet6_ifaddr *ifa;
1197 	struct inet6_dev *idev = ifp->idev;
1198 	unsigned long lifetime;
1199 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1200 
1201 	*expires = jiffies;
1202 
1203 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1204 		if (ifa == ifp)
1205 			continue;
1206 		if (ifa->prefix_len != ifp->prefix_len ||
1207 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1208 				       ifp->prefix_len))
1209 			continue;
1210 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1211 			return CLEANUP_PREFIX_RT_NOP;
1212 
1213 		action = CLEANUP_PREFIX_RT_EXPIRE;
1214 
1215 		spin_lock(&ifa->lock);
1216 
1217 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1218 		/*
1219 		 * Note: Because this address is
1220 		 * not permanent, lifetime <
1221 		 * LONG_MAX / HZ here.
1222 		 */
1223 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1224 			*expires = ifa->tstamp + lifetime * HZ;
1225 		spin_unlock(&ifa->lock);
1226 	}
1227 
1228 	return action;
1229 }
1230 
1231 static void
1232 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1233 {
1234 	struct fib6_info *f6i;
1235 
1236 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
1237 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1238 	if (f6i) {
1239 		if (del_rt)
1240 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1241 		else {
1242 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1243 				fib6_set_expires(f6i, expires);
1244 			fib6_info_release(f6i);
1245 		}
1246 	}
1247 }
1248 
1249 
1250 /* This function wants to get referenced ifp and releases it before return */
1251 
1252 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1253 {
1254 	int state;
1255 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1256 	unsigned long expires;
1257 
1258 	ASSERT_RTNL();
1259 
1260 	spin_lock_bh(&ifp->lock);
1261 	state = ifp->state;
1262 	ifp->state = INET6_IFADDR_STATE_DEAD;
1263 	spin_unlock_bh(&ifp->lock);
1264 
1265 	if (state == INET6_IFADDR_STATE_DEAD)
1266 		goto out;
1267 
1268 	spin_lock_bh(&addrconf_hash_lock);
1269 	hlist_del_init_rcu(&ifp->addr_lst);
1270 	spin_unlock_bh(&addrconf_hash_lock);
1271 
1272 	write_lock_bh(&ifp->idev->lock);
1273 
1274 	if (ifp->flags&IFA_F_TEMPORARY) {
1275 		list_del(&ifp->tmp_list);
1276 		if (ifp->ifpub) {
1277 			in6_ifa_put(ifp->ifpub);
1278 			ifp->ifpub = NULL;
1279 		}
1280 		__in6_ifa_put(ifp);
1281 	}
1282 
1283 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1284 		action = check_cleanup_prefix_route(ifp, &expires);
1285 
1286 	list_del_rcu(&ifp->if_list);
1287 	__in6_ifa_put(ifp);
1288 
1289 	write_unlock_bh(&ifp->idev->lock);
1290 
1291 	addrconf_del_dad_work(ifp);
1292 
1293 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1294 
1295 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1296 
1297 	if (action != CLEANUP_PREFIX_RT_NOP) {
1298 		cleanup_prefix_route(ifp, expires,
1299 			action == CLEANUP_PREFIX_RT_DEL);
1300 	}
1301 
1302 	/* clean up prefsrc entries */
1303 	rt6_remove_prefsrc(ifp);
1304 out:
1305 	in6_ifa_put(ifp);
1306 }
1307 
1308 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1309 				struct inet6_ifaddr *ift,
1310 				bool block)
1311 {
1312 	struct inet6_dev *idev = ifp->idev;
1313 	struct in6_addr addr, *tmpaddr;
1314 	unsigned long tmp_tstamp, age;
1315 	unsigned long regen_advance;
1316 	struct ifa6_config cfg;
1317 	int ret = 0;
1318 	unsigned long now = jiffies;
1319 	long max_desync_factor;
1320 	s32 cnf_temp_preferred_lft;
1321 
1322 	write_lock_bh(&idev->lock);
1323 	if (ift) {
1324 		spin_lock_bh(&ift->lock);
1325 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1326 		spin_unlock_bh(&ift->lock);
1327 		tmpaddr = &addr;
1328 	} else {
1329 		tmpaddr = NULL;
1330 	}
1331 retry:
1332 	in6_dev_hold(idev);
1333 	if (idev->cnf.use_tempaddr <= 0) {
1334 		write_unlock_bh(&idev->lock);
1335 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1336 		in6_dev_put(idev);
1337 		ret = -1;
1338 		goto out;
1339 	}
1340 	spin_lock_bh(&ifp->lock);
1341 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1342 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1343 		spin_unlock_bh(&ifp->lock);
1344 		write_unlock_bh(&idev->lock);
1345 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1346 			__func__);
1347 		in6_dev_put(idev);
1348 		ret = -1;
1349 		goto out;
1350 	}
1351 	in6_ifa_hold(ifp);
1352 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1353 	ipv6_try_regen_rndid(idev, tmpaddr);
1354 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1355 	age = (now - ifp->tstamp) / HZ;
1356 
1357 	regen_advance = idev->cnf.regen_max_retry *
1358 			idev->cnf.dad_transmits *
1359 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1360 
1361 	/* recalculate max_desync_factor each time and update
1362 	 * idev->desync_factor if it's larger
1363 	 */
1364 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1365 	max_desync_factor = min_t(__u32,
1366 				  idev->cnf.max_desync_factor,
1367 				  cnf_temp_preferred_lft - regen_advance);
1368 
1369 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1370 		if (max_desync_factor > 0) {
1371 			get_random_bytes(&idev->desync_factor,
1372 					 sizeof(idev->desync_factor));
1373 			idev->desync_factor %= max_desync_factor;
1374 		} else {
1375 			idev->desync_factor = 0;
1376 		}
1377 	}
1378 
1379 	memset(&cfg, 0, sizeof(cfg));
1380 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1381 			      idev->cnf.temp_valid_lft + age);
1382 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1383 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1384 
1385 	cfg.plen = ifp->prefix_len;
1386 	tmp_tstamp = ifp->tstamp;
1387 	spin_unlock_bh(&ifp->lock);
1388 
1389 	write_unlock_bh(&idev->lock);
1390 
1391 	/* A temporary address is created only if this calculated Preferred
1392 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1393 	 * an implementation must not create a temporary address with a zero
1394 	 * Preferred Lifetime.
1395 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1396 	 * temporary addresses being generated.
1397 	 */
1398 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1399 	if (cfg.preferred_lft <= regen_advance + age) {
1400 		in6_ifa_put(ifp);
1401 		in6_dev_put(idev);
1402 		ret = -1;
1403 		goto out;
1404 	}
1405 
1406 	cfg.ifa_flags = IFA_F_TEMPORARY;
1407 	/* set in addrconf_prefix_rcv() */
1408 	if (ifp->flags & IFA_F_OPTIMISTIC)
1409 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1410 
1411 	cfg.pfx = &addr;
1412 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1413 
1414 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1415 	if (IS_ERR(ift)) {
1416 		in6_ifa_put(ifp);
1417 		in6_dev_put(idev);
1418 		pr_info("%s: retry temporary address regeneration\n", __func__);
1419 		tmpaddr = &addr;
1420 		write_lock_bh(&idev->lock);
1421 		goto retry;
1422 	}
1423 
1424 	spin_lock_bh(&ift->lock);
1425 	ift->ifpub = ifp;
1426 	ift->cstamp = now;
1427 	ift->tstamp = tmp_tstamp;
1428 	spin_unlock_bh(&ift->lock);
1429 
1430 	addrconf_dad_start(ift);
1431 	in6_ifa_put(ift);
1432 	in6_dev_put(idev);
1433 out:
1434 	return ret;
1435 }
1436 
1437 /*
1438  *	Choose an appropriate source address (RFC3484)
1439  */
1440 enum {
1441 	IPV6_SADDR_RULE_INIT = 0,
1442 	IPV6_SADDR_RULE_LOCAL,
1443 	IPV6_SADDR_RULE_SCOPE,
1444 	IPV6_SADDR_RULE_PREFERRED,
1445 #ifdef CONFIG_IPV6_MIP6
1446 	IPV6_SADDR_RULE_HOA,
1447 #endif
1448 	IPV6_SADDR_RULE_OIF,
1449 	IPV6_SADDR_RULE_LABEL,
1450 	IPV6_SADDR_RULE_PRIVACY,
1451 	IPV6_SADDR_RULE_ORCHID,
1452 	IPV6_SADDR_RULE_PREFIX,
1453 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1454 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1455 #endif
1456 	IPV6_SADDR_RULE_MAX
1457 };
1458 
1459 struct ipv6_saddr_score {
1460 	int			rule;
1461 	int			addr_type;
1462 	struct inet6_ifaddr	*ifa;
1463 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1464 	int			scopedist;
1465 	int			matchlen;
1466 };
1467 
1468 struct ipv6_saddr_dst {
1469 	const struct in6_addr *addr;
1470 	int ifindex;
1471 	int scope;
1472 	int label;
1473 	unsigned int prefs;
1474 };
1475 
1476 static inline int ipv6_saddr_preferred(int type)
1477 {
1478 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1479 		return 1;
1480 	return 0;
1481 }
1482 
1483 static bool ipv6_use_optimistic_addr(struct net *net,
1484 				     struct inet6_dev *idev)
1485 {
1486 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1487 	if (!idev)
1488 		return false;
1489 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1490 		return false;
1491 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1492 		return false;
1493 
1494 	return true;
1495 #else
1496 	return false;
1497 #endif
1498 }
1499 
1500 static bool ipv6_allow_optimistic_dad(struct net *net,
1501 				      struct inet6_dev *idev)
1502 {
1503 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1504 	if (!idev)
1505 		return false;
1506 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1507 		return false;
1508 
1509 	return true;
1510 #else
1511 	return false;
1512 #endif
1513 }
1514 
1515 static int ipv6_get_saddr_eval(struct net *net,
1516 			       struct ipv6_saddr_score *score,
1517 			       struct ipv6_saddr_dst *dst,
1518 			       int i)
1519 {
1520 	int ret;
1521 
1522 	if (i <= score->rule) {
1523 		switch (i) {
1524 		case IPV6_SADDR_RULE_SCOPE:
1525 			ret = score->scopedist;
1526 			break;
1527 		case IPV6_SADDR_RULE_PREFIX:
1528 			ret = score->matchlen;
1529 			break;
1530 		default:
1531 			ret = !!test_bit(i, score->scorebits);
1532 		}
1533 		goto out;
1534 	}
1535 
1536 	switch (i) {
1537 	case IPV6_SADDR_RULE_INIT:
1538 		/* Rule 0: remember if hiscore is not ready yet */
1539 		ret = !!score->ifa;
1540 		break;
1541 	case IPV6_SADDR_RULE_LOCAL:
1542 		/* Rule 1: Prefer same address */
1543 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1544 		break;
1545 	case IPV6_SADDR_RULE_SCOPE:
1546 		/* Rule 2: Prefer appropriate scope
1547 		 *
1548 		 *      ret
1549 		 *       ^
1550 		 *    -1 |  d 15
1551 		 *    ---+--+-+---> scope
1552 		 *       |
1553 		 *       |             d is scope of the destination.
1554 		 *  B-d  |  \
1555 		 *       |   \      <- smaller scope is better if
1556 		 *  B-15 |    \        if scope is enough for destination.
1557 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1558 		 * d-C-1 | /
1559 		 *       |/         <- greater is better
1560 		 *   -C  /             if scope is not enough for destination.
1561 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1562 		 *
1563 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1564 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1565 		 * Assume B = 0 and we get C > 29.
1566 		 */
1567 		ret = __ipv6_addr_src_scope(score->addr_type);
1568 		if (ret >= dst->scope)
1569 			ret = -ret;
1570 		else
1571 			ret -= 128;	/* 30 is enough */
1572 		score->scopedist = ret;
1573 		break;
1574 	case IPV6_SADDR_RULE_PREFERRED:
1575 	    {
1576 		/* Rule 3: Avoid deprecated and optimistic addresses */
1577 		u8 avoid = IFA_F_DEPRECATED;
1578 
1579 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1580 			avoid |= IFA_F_OPTIMISTIC;
1581 		ret = ipv6_saddr_preferred(score->addr_type) ||
1582 		      !(score->ifa->flags & avoid);
1583 		break;
1584 	    }
1585 #ifdef CONFIG_IPV6_MIP6
1586 	case IPV6_SADDR_RULE_HOA:
1587 	    {
1588 		/* Rule 4: Prefer home address */
1589 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1590 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1591 		break;
1592 	    }
1593 #endif
1594 	case IPV6_SADDR_RULE_OIF:
1595 		/* Rule 5: Prefer outgoing interface */
1596 		ret = (!dst->ifindex ||
1597 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1598 		break;
1599 	case IPV6_SADDR_RULE_LABEL:
1600 		/* Rule 6: Prefer matching label */
1601 		ret = ipv6_addr_label(net,
1602 				      &score->ifa->addr, score->addr_type,
1603 				      score->ifa->idev->dev->ifindex) == dst->label;
1604 		break;
1605 	case IPV6_SADDR_RULE_PRIVACY:
1606 	    {
1607 		/* Rule 7: Prefer public address
1608 		 * Note: prefer temporary address if use_tempaddr >= 2
1609 		 */
1610 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1611 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1612 				score->ifa->idev->cnf.use_tempaddr >= 2;
1613 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1614 		break;
1615 	    }
1616 	case IPV6_SADDR_RULE_ORCHID:
1617 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1618 		 *	    non-ORCHID vs non-ORCHID
1619 		 */
1620 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1621 			ipv6_addr_orchid(dst->addr));
1622 		break;
1623 	case IPV6_SADDR_RULE_PREFIX:
1624 		/* Rule 8: Use longest matching prefix */
1625 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1626 		if (ret > score->ifa->prefix_len)
1627 			ret = score->ifa->prefix_len;
1628 		score->matchlen = ret;
1629 		break;
1630 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1631 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1632 		/* Optimistic addresses still have lower precedence than other
1633 		 * preferred addresses.
1634 		 */
1635 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1636 		break;
1637 #endif
1638 	default:
1639 		ret = 0;
1640 	}
1641 
1642 	if (ret)
1643 		__set_bit(i, score->scorebits);
1644 	score->rule = i;
1645 out:
1646 	return ret;
1647 }
1648 
1649 static int __ipv6_dev_get_saddr(struct net *net,
1650 				struct ipv6_saddr_dst *dst,
1651 				struct inet6_dev *idev,
1652 				struct ipv6_saddr_score *scores,
1653 				int hiscore_idx)
1654 {
1655 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1656 
1657 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1658 		int i;
1659 
1660 		/*
1661 		 * - Tentative Address (RFC2462 section 5.4)
1662 		 *  - A tentative address is not considered
1663 		 *    "assigned to an interface" in the traditional
1664 		 *    sense, unless it is also flagged as optimistic.
1665 		 * - Candidate Source Address (section 4)
1666 		 *  - In any case, anycast addresses, multicast
1667 		 *    addresses, and the unspecified address MUST
1668 		 *    NOT be included in a candidate set.
1669 		 */
1670 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1671 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1672 			continue;
1673 
1674 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1675 
1676 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1677 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1678 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1679 					    idev->dev->name);
1680 			continue;
1681 		}
1682 
1683 		score->rule = -1;
1684 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1685 
1686 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1687 			int minihiscore, miniscore;
1688 
1689 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1690 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1691 
1692 			if (minihiscore > miniscore) {
1693 				if (i == IPV6_SADDR_RULE_SCOPE &&
1694 				    score->scopedist > 0) {
1695 					/*
1696 					 * special case:
1697 					 * each remaining entry
1698 					 * has too small (not enough)
1699 					 * scope, because ifa entries
1700 					 * are sorted by their scope
1701 					 * values.
1702 					 */
1703 					goto out;
1704 				}
1705 				break;
1706 			} else if (minihiscore < miniscore) {
1707 				swap(hiscore, score);
1708 				hiscore_idx = 1 - hiscore_idx;
1709 
1710 				/* restore our iterator */
1711 				score->ifa = hiscore->ifa;
1712 
1713 				break;
1714 			}
1715 		}
1716 	}
1717 out:
1718 	return hiscore_idx;
1719 }
1720 
1721 static int ipv6_get_saddr_master(struct net *net,
1722 				 const struct net_device *dst_dev,
1723 				 const struct net_device *master,
1724 				 struct ipv6_saddr_dst *dst,
1725 				 struct ipv6_saddr_score *scores,
1726 				 int hiscore_idx)
1727 {
1728 	struct inet6_dev *idev;
1729 
1730 	idev = __in6_dev_get(dst_dev);
1731 	if (idev)
1732 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1733 						   scores, hiscore_idx);
1734 
1735 	idev = __in6_dev_get(master);
1736 	if (idev)
1737 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1738 						   scores, hiscore_idx);
1739 
1740 	return hiscore_idx;
1741 }
1742 
1743 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1744 		       const struct in6_addr *daddr, unsigned int prefs,
1745 		       struct in6_addr *saddr)
1746 {
1747 	struct ipv6_saddr_score scores[2], *hiscore;
1748 	struct ipv6_saddr_dst dst;
1749 	struct inet6_dev *idev;
1750 	struct net_device *dev;
1751 	int dst_type;
1752 	bool use_oif_addr = false;
1753 	int hiscore_idx = 0;
1754 	int ret = 0;
1755 
1756 	dst_type = __ipv6_addr_type(daddr);
1757 	dst.addr = daddr;
1758 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1759 	dst.scope = __ipv6_addr_src_scope(dst_type);
1760 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1761 	dst.prefs = prefs;
1762 
1763 	scores[hiscore_idx].rule = -1;
1764 	scores[hiscore_idx].ifa = NULL;
1765 
1766 	rcu_read_lock();
1767 
1768 	/* Candidate Source Address (section 4)
1769 	 *  - multicast and link-local destination address,
1770 	 *    the set of candidate source address MUST only
1771 	 *    include addresses assigned to interfaces
1772 	 *    belonging to the same link as the outgoing
1773 	 *    interface.
1774 	 * (- For site-local destination addresses, the
1775 	 *    set of candidate source addresses MUST only
1776 	 *    include addresses assigned to interfaces
1777 	 *    belonging to the same site as the outgoing
1778 	 *    interface.)
1779 	 *  - "It is RECOMMENDED that the candidate source addresses
1780 	 *    be the set of unicast addresses assigned to the
1781 	 *    interface that will be used to send to the destination
1782 	 *    (the 'outgoing' interface)." (RFC 6724)
1783 	 */
1784 	if (dst_dev) {
1785 		idev = __in6_dev_get(dst_dev);
1786 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1787 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1788 		    (idev && idev->cnf.use_oif_addrs_only)) {
1789 			use_oif_addr = true;
1790 		}
1791 	}
1792 
1793 	if (use_oif_addr) {
1794 		if (idev)
1795 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1796 	} else {
1797 		const struct net_device *master;
1798 		int master_idx = 0;
1799 
1800 		/* if dst_dev exists and is enslaved to an L3 device, then
1801 		 * prefer addresses from dst_dev and then the master over
1802 		 * any other enslaved devices in the L3 domain.
1803 		 */
1804 		master = l3mdev_master_dev_rcu(dst_dev);
1805 		if (master) {
1806 			master_idx = master->ifindex;
1807 
1808 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1809 							    master, &dst,
1810 							    scores, hiscore_idx);
1811 
1812 			if (scores[hiscore_idx].ifa)
1813 				goto out;
1814 		}
1815 
1816 		for_each_netdev_rcu(net, dev) {
1817 			/* only consider addresses on devices in the
1818 			 * same L3 domain
1819 			 */
1820 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1821 				continue;
1822 			idev = __in6_dev_get(dev);
1823 			if (!idev)
1824 				continue;
1825 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1826 		}
1827 	}
1828 
1829 out:
1830 	hiscore = &scores[hiscore_idx];
1831 	if (!hiscore->ifa)
1832 		ret = -EADDRNOTAVAIL;
1833 	else
1834 		*saddr = hiscore->ifa->addr;
1835 
1836 	rcu_read_unlock();
1837 	return ret;
1838 }
1839 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1840 
1841 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1842 		      u32 banned_flags)
1843 {
1844 	struct inet6_ifaddr *ifp;
1845 	int err = -EADDRNOTAVAIL;
1846 
1847 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1848 		if (ifp->scope > IFA_LINK)
1849 			break;
1850 		if (ifp->scope == IFA_LINK &&
1851 		    !(ifp->flags & banned_flags)) {
1852 			*addr = ifp->addr;
1853 			err = 0;
1854 			break;
1855 		}
1856 	}
1857 	return err;
1858 }
1859 
1860 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1861 		    u32 banned_flags)
1862 {
1863 	struct inet6_dev *idev;
1864 	int err = -EADDRNOTAVAIL;
1865 
1866 	rcu_read_lock();
1867 	idev = __in6_dev_get(dev);
1868 	if (idev) {
1869 		read_lock_bh(&idev->lock);
1870 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1871 		read_unlock_bh(&idev->lock);
1872 	}
1873 	rcu_read_unlock();
1874 	return err;
1875 }
1876 
1877 static int ipv6_count_addresses(const struct inet6_dev *idev)
1878 {
1879 	const struct inet6_ifaddr *ifp;
1880 	int cnt = 0;
1881 
1882 	rcu_read_lock();
1883 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1884 		cnt++;
1885 	rcu_read_unlock();
1886 	return cnt;
1887 }
1888 
1889 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1890 		  const struct net_device *dev, int strict)
1891 {
1892 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1893 				       strict, IFA_F_TENTATIVE);
1894 }
1895 EXPORT_SYMBOL(ipv6_chk_addr);
1896 
1897 /* device argument is used to find the L3 domain of interest. If
1898  * skip_dev_check is set, then the ifp device is not checked against
1899  * the passed in dev argument. So the 2 cases for addresses checks are:
1900  *   1. does the address exist in the L3 domain that dev is part of
1901  *      (skip_dev_check = true), or
1902  *
1903  *   2. does the address exist on the specific device
1904  *      (skip_dev_check = false)
1905  */
1906 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1907 			    const struct net_device *dev, bool skip_dev_check,
1908 			    int strict, u32 banned_flags)
1909 {
1910 	unsigned int hash = inet6_addr_hash(net, addr);
1911 	const struct net_device *l3mdev;
1912 	struct inet6_ifaddr *ifp;
1913 	u32 ifp_flags;
1914 
1915 	rcu_read_lock();
1916 
1917 	l3mdev = l3mdev_master_dev_rcu(dev);
1918 	if (skip_dev_check)
1919 		dev = NULL;
1920 
1921 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1922 		if (!net_eq(dev_net(ifp->idev->dev), net))
1923 			continue;
1924 
1925 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1926 			continue;
1927 
1928 		/* Decouple optimistic from tentative for evaluation here.
1929 		 * Ban optimistic addresses explicitly, when required.
1930 		 */
1931 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1932 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1933 			    : ifp->flags;
1934 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1935 		    !(ifp_flags&banned_flags) &&
1936 		    (!dev || ifp->idev->dev == dev ||
1937 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1938 			rcu_read_unlock();
1939 			return 1;
1940 		}
1941 	}
1942 
1943 	rcu_read_unlock();
1944 	return 0;
1945 }
1946 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1947 
1948 
1949 /* Compares an address/prefix_len with addresses on device @dev.
1950  * If one is found it returns true.
1951  */
1952 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1953 	const unsigned int prefix_len, struct net_device *dev)
1954 {
1955 	const struct inet6_ifaddr *ifa;
1956 	const struct inet6_dev *idev;
1957 	bool ret = false;
1958 
1959 	rcu_read_lock();
1960 	idev = __in6_dev_get(dev);
1961 	if (idev) {
1962 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1963 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1964 			if (ret)
1965 				break;
1966 		}
1967 	}
1968 	rcu_read_unlock();
1969 
1970 	return ret;
1971 }
1972 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1973 
1974 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1975 {
1976 	const struct inet6_ifaddr *ifa;
1977 	const struct inet6_dev *idev;
1978 	int	onlink;
1979 
1980 	onlink = 0;
1981 	rcu_read_lock();
1982 	idev = __in6_dev_get(dev);
1983 	if (idev) {
1984 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1985 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1986 						   ifa->prefix_len);
1987 			if (onlink)
1988 				break;
1989 		}
1990 	}
1991 	rcu_read_unlock();
1992 	return onlink;
1993 }
1994 EXPORT_SYMBOL(ipv6_chk_prefix);
1995 
1996 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1997 				     struct net_device *dev, int strict)
1998 {
1999 	unsigned int hash = inet6_addr_hash(net, addr);
2000 	struct inet6_ifaddr *ifp, *result = NULL;
2001 
2002 	rcu_read_lock();
2003 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2004 		if (!net_eq(dev_net(ifp->idev->dev), net))
2005 			continue;
2006 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2007 			if (!dev || ifp->idev->dev == dev ||
2008 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2009 				result = ifp;
2010 				in6_ifa_hold(ifp);
2011 				break;
2012 			}
2013 		}
2014 	}
2015 	rcu_read_unlock();
2016 
2017 	return result;
2018 }
2019 
2020 /* Gets referenced address, destroys ifaddr */
2021 
2022 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2023 {
2024 	if (dad_failed)
2025 		ifp->flags |= IFA_F_DADFAILED;
2026 
2027 	if (ifp->flags&IFA_F_TEMPORARY) {
2028 		struct inet6_ifaddr *ifpub;
2029 		spin_lock_bh(&ifp->lock);
2030 		ifpub = ifp->ifpub;
2031 		if (ifpub) {
2032 			in6_ifa_hold(ifpub);
2033 			spin_unlock_bh(&ifp->lock);
2034 			ipv6_create_tempaddr(ifpub, ifp, true);
2035 			in6_ifa_put(ifpub);
2036 		} else {
2037 			spin_unlock_bh(&ifp->lock);
2038 		}
2039 		ipv6_del_addr(ifp);
2040 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2041 		spin_lock_bh(&ifp->lock);
2042 		addrconf_del_dad_work(ifp);
2043 		ifp->flags |= IFA_F_TENTATIVE;
2044 		if (dad_failed)
2045 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2046 		spin_unlock_bh(&ifp->lock);
2047 		if (dad_failed)
2048 			ipv6_ifa_notify(0, ifp);
2049 		in6_ifa_put(ifp);
2050 	} else {
2051 		ipv6_del_addr(ifp);
2052 	}
2053 }
2054 
2055 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2056 {
2057 	int err = -ENOENT;
2058 
2059 	spin_lock_bh(&ifp->lock);
2060 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2061 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2062 		err = 0;
2063 	}
2064 	spin_unlock_bh(&ifp->lock);
2065 
2066 	return err;
2067 }
2068 
2069 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2070 {
2071 	struct inet6_dev *idev = ifp->idev;
2072 	struct net *net = dev_net(ifp->idev->dev);
2073 
2074 	if (addrconf_dad_end(ifp)) {
2075 		in6_ifa_put(ifp);
2076 		return;
2077 	}
2078 
2079 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2080 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2081 
2082 	spin_lock_bh(&ifp->lock);
2083 
2084 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2085 		struct in6_addr new_addr;
2086 		struct inet6_ifaddr *ifp2;
2087 		int retries = ifp->stable_privacy_retry + 1;
2088 		struct ifa6_config cfg = {
2089 			.pfx = &new_addr,
2090 			.plen = ifp->prefix_len,
2091 			.ifa_flags = ifp->flags,
2092 			.valid_lft = ifp->valid_lft,
2093 			.preferred_lft = ifp->prefered_lft,
2094 			.scope = ifp->scope,
2095 		};
2096 
2097 		if (retries > net->ipv6.sysctl.idgen_retries) {
2098 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2099 					     ifp->idev->dev->name);
2100 			goto errdad;
2101 		}
2102 
2103 		new_addr = ifp->addr;
2104 		if (ipv6_generate_stable_address(&new_addr, retries,
2105 						 idev))
2106 			goto errdad;
2107 
2108 		spin_unlock_bh(&ifp->lock);
2109 
2110 		if (idev->cnf.max_addresses &&
2111 		    ipv6_count_addresses(idev) >=
2112 		    idev->cnf.max_addresses)
2113 			goto lock_errdad;
2114 
2115 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2116 				     ifp->idev->dev->name);
2117 
2118 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2119 		if (IS_ERR(ifp2))
2120 			goto lock_errdad;
2121 
2122 		spin_lock_bh(&ifp2->lock);
2123 		ifp2->stable_privacy_retry = retries;
2124 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2125 		spin_unlock_bh(&ifp2->lock);
2126 
2127 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2128 		in6_ifa_put(ifp2);
2129 lock_errdad:
2130 		spin_lock_bh(&ifp->lock);
2131 	}
2132 
2133 errdad:
2134 	/* transition from _POSTDAD to _ERRDAD */
2135 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2136 	spin_unlock_bh(&ifp->lock);
2137 
2138 	addrconf_mod_dad_work(ifp, 0);
2139 	in6_ifa_put(ifp);
2140 }
2141 
2142 /* Join to solicited addr multicast group.
2143  * caller must hold RTNL */
2144 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2145 {
2146 	struct in6_addr maddr;
2147 
2148 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2149 		return;
2150 
2151 	addrconf_addr_solict_mult(addr, &maddr);
2152 	ipv6_dev_mc_inc(dev, &maddr);
2153 }
2154 
2155 /* caller must hold RTNL */
2156 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2157 {
2158 	struct in6_addr maddr;
2159 
2160 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2161 		return;
2162 
2163 	addrconf_addr_solict_mult(addr, &maddr);
2164 	__ipv6_dev_mc_dec(idev, &maddr);
2165 }
2166 
2167 /* caller must hold RTNL */
2168 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2169 {
2170 	struct in6_addr addr;
2171 
2172 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2173 		return;
2174 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2175 	if (ipv6_addr_any(&addr))
2176 		return;
2177 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2178 }
2179 
2180 /* caller must hold RTNL */
2181 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2182 {
2183 	struct in6_addr addr;
2184 
2185 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2186 		return;
2187 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2188 	if (ipv6_addr_any(&addr))
2189 		return;
2190 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2191 }
2192 
2193 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2194 {
2195 	switch (dev->addr_len) {
2196 	case ETH_ALEN:
2197 		memcpy(eui, dev->dev_addr, 3);
2198 		eui[3] = 0xFF;
2199 		eui[4] = 0xFE;
2200 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2201 		break;
2202 	case EUI64_ADDR_LEN:
2203 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2204 		eui[0] ^= 2;
2205 		break;
2206 	default:
2207 		return -1;
2208 	}
2209 
2210 	return 0;
2211 }
2212 
2213 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2214 {
2215 	union fwnet_hwaddr *ha;
2216 
2217 	if (dev->addr_len != FWNET_ALEN)
2218 		return -1;
2219 
2220 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2221 
2222 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2223 	eui[0] ^= 2;
2224 	return 0;
2225 }
2226 
2227 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2228 {
2229 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2230 	if (dev->addr_len != ARCNET_ALEN)
2231 		return -1;
2232 	memset(eui, 0, 7);
2233 	eui[7] = *(u8 *)dev->dev_addr;
2234 	return 0;
2235 }
2236 
2237 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2238 {
2239 	if (dev->addr_len != INFINIBAND_ALEN)
2240 		return -1;
2241 	memcpy(eui, dev->dev_addr + 12, 8);
2242 	eui[0] |= 2;
2243 	return 0;
2244 }
2245 
2246 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2247 {
2248 	if (addr == 0)
2249 		return -1;
2250 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2251 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2252 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2253 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2254 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2255 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2256 	eui[1] = 0;
2257 	eui[2] = 0x5E;
2258 	eui[3] = 0xFE;
2259 	memcpy(eui + 4, &addr, 4);
2260 	return 0;
2261 }
2262 
2263 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2264 {
2265 	if (dev->priv_flags & IFF_ISATAP)
2266 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2267 	return -1;
2268 }
2269 
2270 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2271 {
2272 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2273 }
2274 
2275 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2276 {
2277 	memcpy(eui, dev->perm_addr, 3);
2278 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2279 	eui[3] = 0xFF;
2280 	eui[4] = 0xFE;
2281 	eui[0] ^= 2;
2282 	return 0;
2283 }
2284 
2285 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2286 {
2287 	switch (dev->type) {
2288 	case ARPHRD_ETHER:
2289 	case ARPHRD_FDDI:
2290 		return addrconf_ifid_eui48(eui, dev);
2291 	case ARPHRD_ARCNET:
2292 		return addrconf_ifid_arcnet(eui, dev);
2293 	case ARPHRD_INFINIBAND:
2294 		return addrconf_ifid_infiniband(eui, dev);
2295 	case ARPHRD_SIT:
2296 		return addrconf_ifid_sit(eui, dev);
2297 	case ARPHRD_IPGRE:
2298 	case ARPHRD_TUNNEL:
2299 		return addrconf_ifid_gre(eui, dev);
2300 	case ARPHRD_6LOWPAN:
2301 		return addrconf_ifid_6lowpan(eui, dev);
2302 	case ARPHRD_IEEE1394:
2303 		return addrconf_ifid_ieee1394(eui, dev);
2304 	case ARPHRD_TUNNEL6:
2305 	case ARPHRD_IP6GRE:
2306 	case ARPHRD_RAWIP:
2307 		return addrconf_ifid_ip6tnl(eui, dev);
2308 	}
2309 	return -1;
2310 }
2311 
2312 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2313 {
2314 	int err = -1;
2315 	struct inet6_ifaddr *ifp;
2316 
2317 	read_lock_bh(&idev->lock);
2318 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2319 		if (ifp->scope > IFA_LINK)
2320 			break;
2321 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2322 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2323 			err = 0;
2324 			break;
2325 		}
2326 	}
2327 	read_unlock_bh(&idev->lock);
2328 	return err;
2329 }
2330 
2331 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2332 static void ipv6_regen_rndid(struct inet6_dev *idev)
2333 {
2334 regen:
2335 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2336 	idev->rndid[0] &= ~0x02;
2337 
2338 	/*
2339 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2340 	 * check if generated address is not inappropriate
2341 	 *
2342 	 *  - Reserved subnet anycast (RFC 2526)
2343 	 *	11111101 11....11 1xxxxxxx
2344 	 *  - ISATAP (RFC4214) 6.1
2345 	 *	00-00-5E-FE-xx-xx-xx-xx
2346 	 *  - value 0
2347 	 *  - XXX: already assigned to an address on the device
2348 	 */
2349 	if (idev->rndid[0] == 0xfd &&
2350 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2351 	    (idev->rndid[7]&0x80))
2352 		goto regen;
2353 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2354 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2355 			goto regen;
2356 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2357 			goto regen;
2358 	}
2359 }
2360 
2361 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2362 {
2363 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2364 		ipv6_regen_rndid(idev);
2365 }
2366 
2367 /*
2368  *	Add prefix route.
2369  */
2370 
2371 static void
2372 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2373 		      struct net_device *dev, unsigned long expires,
2374 		      u32 flags, gfp_t gfp_flags)
2375 {
2376 	struct fib6_config cfg = {
2377 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2378 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2379 		.fc_ifindex = dev->ifindex,
2380 		.fc_expires = expires,
2381 		.fc_dst_len = plen,
2382 		.fc_flags = RTF_UP | flags,
2383 		.fc_nlinfo.nl_net = dev_net(dev),
2384 		.fc_protocol = RTPROT_KERNEL,
2385 		.fc_type = RTN_UNICAST,
2386 	};
2387 
2388 	cfg.fc_dst = *pfx;
2389 
2390 	/* Prevent useless cloning on PtP SIT.
2391 	   This thing is done here expecting that the whole
2392 	   class of non-broadcast devices need not cloning.
2393 	 */
2394 #if IS_ENABLED(CONFIG_IPV6_SIT)
2395 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2396 		cfg.fc_flags |= RTF_NONEXTHOP;
2397 #endif
2398 
2399 	ip6_route_add(&cfg, gfp_flags, NULL);
2400 }
2401 
2402 
2403 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2404 						  int plen,
2405 						  const struct net_device *dev,
2406 						  u32 flags, u32 noflags,
2407 						  bool no_gw)
2408 {
2409 	struct fib6_node *fn;
2410 	struct fib6_info *rt = NULL;
2411 	struct fib6_table *table;
2412 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2413 
2414 	table = fib6_get_table(dev_net(dev), tb_id);
2415 	if (!table)
2416 		return NULL;
2417 
2418 	rcu_read_lock();
2419 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2420 	if (!fn)
2421 		goto out;
2422 
2423 	for_each_fib6_node_rt_rcu(fn) {
2424 		if (rt->fib6_nh.fib_nh_dev->ifindex != dev->ifindex)
2425 			continue;
2426 		if (no_gw && rt->fib6_nh.fib_nh_gw_family)
2427 			continue;
2428 		if ((rt->fib6_flags & flags) != flags)
2429 			continue;
2430 		if ((rt->fib6_flags & noflags) != 0)
2431 			continue;
2432 		if (!fib6_info_hold_safe(rt))
2433 			continue;
2434 		break;
2435 	}
2436 out:
2437 	rcu_read_unlock();
2438 	return rt;
2439 }
2440 
2441 
2442 /* Create "default" multicast route to the interface */
2443 
2444 static void addrconf_add_mroute(struct net_device *dev)
2445 {
2446 	struct fib6_config cfg = {
2447 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2448 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2449 		.fc_ifindex = dev->ifindex,
2450 		.fc_dst_len = 8,
2451 		.fc_flags = RTF_UP,
2452 		.fc_type = RTN_UNICAST,
2453 		.fc_nlinfo.nl_net = dev_net(dev),
2454 	};
2455 
2456 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2457 
2458 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2459 }
2460 
2461 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2462 {
2463 	struct inet6_dev *idev;
2464 
2465 	ASSERT_RTNL();
2466 
2467 	idev = ipv6_find_idev(dev);
2468 	if (!idev)
2469 		return ERR_PTR(-ENOBUFS);
2470 
2471 	if (idev->cnf.disable_ipv6)
2472 		return ERR_PTR(-EACCES);
2473 
2474 	/* Add default multicast route */
2475 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2476 		addrconf_add_mroute(dev);
2477 
2478 	return idev;
2479 }
2480 
2481 static void manage_tempaddrs(struct inet6_dev *idev,
2482 			     struct inet6_ifaddr *ifp,
2483 			     __u32 valid_lft, __u32 prefered_lft,
2484 			     bool create, unsigned long now)
2485 {
2486 	u32 flags;
2487 	struct inet6_ifaddr *ift;
2488 
2489 	read_lock_bh(&idev->lock);
2490 	/* update all temporary addresses in the list */
2491 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2492 		int age, max_valid, max_prefered;
2493 
2494 		if (ifp != ift->ifpub)
2495 			continue;
2496 
2497 		/* RFC 4941 section 3.3:
2498 		 * If a received option will extend the lifetime of a public
2499 		 * address, the lifetimes of temporary addresses should
2500 		 * be extended, subject to the overall constraint that no
2501 		 * temporary addresses should ever remain "valid" or "preferred"
2502 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2503 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2504 		 */
2505 		age = (now - ift->cstamp) / HZ;
2506 		max_valid = idev->cnf.temp_valid_lft - age;
2507 		if (max_valid < 0)
2508 			max_valid = 0;
2509 
2510 		max_prefered = idev->cnf.temp_prefered_lft -
2511 			       idev->desync_factor - age;
2512 		if (max_prefered < 0)
2513 			max_prefered = 0;
2514 
2515 		if (valid_lft > max_valid)
2516 			valid_lft = max_valid;
2517 
2518 		if (prefered_lft > max_prefered)
2519 			prefered_lft = max_prefered;
2520 
2521 		spin_lock(&ift->lock);
2522 		flags = ift->flags;
2523 		ift->valid_lft = valid_lft;
2524 		ift->prefered_lft = prefered_lft;
2525 		ift->tstamp = now;
2526 		if (prefered_lft > 0)
2527 			ift->flags &= ~IFA_F_DEPRECATED;
2528 
2529 		spin_unlock(&ift->lock);
2530 		if (!(flags&IFA_F_TENTATIVE))
2531 			ipv6_ifa_notify(0, ift);
2532 	}
2533 
2534 	if ((create || list_empty(&idev->tempaddr_list)) &&
2535 	    idev->cnf.use_tempaddr > 0) {
2536 		/* When a new public address is created as described
2537 		 * in [ADDRCONF], also create a new temporary address.
2538 		 * Also create a temporary address if it's enabled but
2539 		 * no temporary address currently exists.
2540 		 */
2541 		read_unlock_bh(&idev->lock);
2542 		ipv6_create_tempaddr(ifp, NULL, false);
2543 	} else {
2544 		read_unlock_bh(&idev->lock);
2545 	}
2546 }
2547 
2548 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2549 {
2550 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2551 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2552 }
2553 
2554 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2555 				 const struct prefix_info *pinfo,
2556 				 struct inet6_dev *in6_dev,
2557 				 const struct in6_addr *addr, int addr_type,
2558 				 u32 addr_flags, bool sllao, bool tokenized,
2559 				 __u32 valid_lft, u32 prefered_lft)
2560 {
2561 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2562 	int create = 0, update_lft = 0;
2563 
2564 	if (!ifp && valid_lft) {
2565 		int max_addresses = in6_dev->cnf.max_addresses;
2566 		struct ifa6_config cfg = {
2567 			.pfx = addr,
2568 			.plen = pinfo->prefix_len,
2569 			.ifa_flags = addr_flags,
2570 			.valid_lft = valid_lft,
2571 			.preferred_lft = prefered_lft,
2572 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2573 		};
2574 
2575 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2576 		if ((net->ipv6.devconf_all->optimistic_dad ||
2577 		     in6_dev->cnf.optimistic_dad) &&
2578 		    !net->ipv6.devconf_all->forwarding && sllao)
2579 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2580 #endif
2581 
2582 		/* Do not allow to create too much of autoconfigured
2583 		 * addresses; this would be too easy way to crash kernel.
2584 		 */
2585 		if (!max_addresses ||
2586 		    ipv6_count_addresses(in6_dev) < max_addresses)
2587 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2588 
2589 		if (IS_ERR_OR_NULL(ifp))
2590 			return -1;
2591 
2592 		create = 1;
2593 		spin_lock_bh(&ifp->lock);
2594 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2595 		ifp->cstamp = jiffies;
2596 		ifp->tokenized = tokenized;
2597 		spin_unlock_bh(&ifp->lock);
2598 		addrconf_dad_start(ifp);
2599 	}
2600 
2601 	if (ifp) {
2602 		u32 flags;
2603 		unsigned long now;
2604 		u32 stored_lft;
2605 
2606 		/* update lifetime (RFC2462 5.5.3 e) */
2607 		spin_lock_bh(&ifp->lock);
2608 		now = jiffies;
2609 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2610 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2611 		else
2612 			stored_lft = 0;
2613 		if (!create && stored_lft) {
2614 			const u32 minimum_lft = min_t(u32,
2615 				stored_lft, MIN_VALID_LIFETIME);
2616 			valid_lft = max(valid_lft, minimum_lft);
2617 
2618 			/* RFC4862 Section 5.5.3e:
2619 			 * "Note that the preferred lifetime of the
2620 			 *  corresponding address is always reset to
2621 			 *  the Preferred Lifetime in the received
2622 			 *  Prefix Information option, regardless of
2623 			 *  whether the valid lifetime is also reset or
2624 			 *  ignored."
2625 			 *
2626 			 * So we should always update prefered_lft here.
2627 			 */
2628 			update_lft = 1;
2629 		}
2630 
2631 		if (update_lft) {
2632 			ifp->valid_lft = valid_lft;
2633 			ifp->prefered_lft = prefered_lft;
2634 			ifp->tstamp = now;
2635 			flags = ifp->flags;
2636 			ifp->flags &= ~IFA_F_DEPRECATED;
2637 			spin_unlock_bh(&ifp->lock);
2638 
2639 			if (!(flags&IFA_F_TENTATIVE))
2640 				ipv6_ifa_notify(0, ifp);
2641 		} else
2642 			spin_unlock_bh(&ifp->lock);
2643 
2644 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2645 				 create, now);
2646 
2647 		in6_ifa_put(ifp);
2648 		addrconf_verify();
2649 	}
2650 
2651 	return 0;
2652 }
2653 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2654 
2655 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2656 {
2657 	struct prefix_info *pinfo;
2658 	__u32 valid_lft;
2659 	__u32 prefered_lft;
2660 	int addr_type, err;
2661 	u32 addr_flags = 0;
2662 	struct inet6_dev *in6_dev;
2663 	struct net *net = dev_net(dev);
2664 
2665 	pinfo = (struct prefix_info *) opt;
2666 
2667 	if (len < sizeof(struct prefix_info)) {
2668 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2669 		return;
2670 	}
2671 
2672 	/*
2673 	 *	Validation checks ([ADDRCONF], page 19)
2674 	 */
2675 
2676 	addr_type = ipv6_addr_type(&pinfo->prefix);
2677 
2678 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2679 		return;
2680 
2681 	valid_lft = ntohl(pinfo->valid);
2682 	prefered_lft = ntohl(pinfo->prefered);
2683 
2684 	if (prefered_lft > valid_lft) {
2685 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2686 		return;
2687 	}
2688 
2689 	in6_dev = in6_dev_get(dev);
2690 
2691 	if (!in6_dev) {
2692 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2693 				    dev->name);
2694 		return;
2695 	}
2696 
2697 	/*
2698 	 *	Two things going on here:
2699 	 *	1) Add routes for on-link prefixes
2700 	 *	2) Configure prefixes with the auto flag set
2701 	 */
2702 
2703 	if (pinfo->onlink) {
2704 		struct fib6_info *rt;
2705 		unsigned long rt_expires;
2706 
2707 		/* Avoid arithmetic overflow. Really, we could
2708 		 * save rt_expires in seconds, likely valid_lft,
2709 		 * but it would require division in fib gc, that it
2710 		 * not good.
2711 		 */
2712 		if (HZ > USER_HZ)
2713 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2714 		else
2715 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2716 
2717 		if (addrconf_finite_timeout(rt_expires))
2718 			rt_expires *= HZ;
2719 
2720 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2721 					       pinfo->prefix_len,
2722 					       dev,
2723 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2724 					       RTF_DEFAULT, true);
2725 
2726 		if (rt) {
2727 			/* Autoconf prefix route */
2728 			if (valid_lft == 0) {
2729 				ip6_del_rt(net, rt);
2730 				rt = NULL;
2731 			} else if (addrconf_finite_timeout(rt_expires)) {
2732 				/* not infinity */
2733 				fib6_set_expires(rt, jiffies + rt_expires);
2734 			} else {
2735 				fib6_clean_expires(rt);
2736 			}
2737 		} else if (valid_lft) {
2738 			clock_t expires = 0;
2739 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2740 			if (addrconf_finite_timeout(rt_expires)) {
2741 				/* not infinity */
2742 				flags |= RTF_EXPIRES;
2743 				expires = jiffies_to_clock_t(rt_expires);
2744 			}
2745 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2746 					      0, dev, expires, flags,
2747 					      GFP_ATOMIC);
2748 		}
2749 		fib6_info_release(rt);
2750 	}
2751 
2752 	/* Try to figure out our local address for this prefix */
2753 
2754 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2755 		struct in6_addr addr;
2756 		bool tokenized = false, dev_addr_generated = false;
2757 
2758 		if (pinfo->prefix_len == 64) {
2759 			memcpy(&addr, &pinfo->prefix, 8);
2760 
2761 			if (!ipv6_addr_any(&in6_dev->token)) {
2762 				read_lock_bh(&in6_dev->lock);
2763 				memcpy(addr.s6_addr + 8,
2764 				       in6_dev->token.s6_addr + 8, 8);
2765 				read_unlock_bh(&in6_dev->lock);
2766 				tokenized = true;
2767 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2768 				   !ipv6_generate_stable_address(&addr, 0,
2769 								 in6_dev)) {
2770 				addr_flags |= IFA_F_STABLE_PRIVACY;
2771 				goto ok;
2772 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2773 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2774 				goto put;
2775 			} else {
2776 				dev_addr_generated = true;
2777 			}
2778 			goto ok;
2779 		}
2780 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2781 				    pinfo->prefix_len);
2782 		goto put;
2783 
2784 ok:
2785 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2786 						   &addr, addr_type,
2787 						   addr_flags, sllao,
2788 						   tokenized, valid_lft,
2789 						   prefered_lft);
2790 		if (err)
2791 			goto put;
2792 
2793 		/* Ignore error case here because previous prefix add addr was
2794 		 * successful which will be notified.
2795 		 */
2796 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2797 					      addr_type, addr_flags, sllao,
2798 					      tokenized, valid_lft,
2799 					      prefered_lft,
2800 					      dev_addr_generated);
2801 	}
2802 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2803 put:
2804 	in6_dev_put(in6_dev);
2805 }
2806 
2807 /*
2808  *	Set destination address.
2809  *	Special case for SIT interfaces where we create a new "virtual"
2810  *	device.
2811  */
2812 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2813 {
2814 	struct in6_ifreq ireq;
2815 	struct net_device *dev;
2816 	int err = -EINVAL;
2817 
2818 	rtnl_lock();
2819 
2820 	err = -EFAULT;
2821 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2822 		goto err_exit;
2823 
2824 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2825 
2826 	err = -ENODEV;
2827 	if (!dev)
2828 		goto err_exit;
2829 
2830 #if IS_ENABLED(CONFIG_IPV6_SIT)
2831 	if (dev->type == ARPHRD_SIT) {
2832 		const struct net_device_ops *ops = dev->netdev_ops;
2833 		struct ifreq ifr;
2834 		struct ip_tunnel_parm p;
2835 
2836 		err = -EADDRNOTAVAIL;
2837 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2838 			goto err_exit;
2839 
2840 		memset(&p, 0, sizeof(p));
2841 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2842 		p.iph.saddr = 0;
2843 		p.iph.version = 4;
2844 		p.iph.ihl = 5;
2845 		p.iph.protocol = IPPROTO_IPV6;
2846 		p.iph.ttl = 64;
2847 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2848 
2849 		if (ops->ndo_do_ioctl) {
2850 			mm_segment_t oldfs = get_fs();
2851 
2852 			set_fs(KERNEL_DS);
2853 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2854 			set_fs(oldfs);
2855 		} else
2856 			err = -EOPNOTSUPP;
2857 
2858 		if (err == 0) {
2859 			err = -ENOBUFS;
2860 			dev = __dev_get_by_name(net, p.name);
2861 			if (!dev)
2862 				goto err_exit;
2863 			err = dev_open(dev, NULL);
2864 		}
2865 	}
2866 #endif
2867 
2868 err_exit:
2869 	rtnl_unlock();
2870 	return err;
2871 }
2872 
2873 static int ipv6_mc_config(struct sock *sk, bool join,
2874 			  const struct in6_addr *addr, int ifindex)
2875 {
2876 	int ret;
2877 
2878 	ASSERT_RTNL();
2879 
2880 	lock_sock(sk);
2881 	if (join)
2882 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2883 	else
2884 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2885 	release_sock(sk);
2886 
2887 	return ret;
2888 }
2889 
2890 /*
2891  *	Manual configuration of address on an interface
2892  */
2893 static int inet6_addr_add(struct net *net, int ifindex,
2894 			  struct ifa6_config *cfg,
2895 			  struct netlink_ext_ack *extack)
2896 {
2897 	struct inet6_ifaddr *ifp;
2898 	struct inet6_dev *idev;
2899 	struct net_device *dev;
2900 	unsigned long timeout;
2901 	clock_t expires;
2902 	u32 flags;
2903 
2904 	ASSERT_RTNL();
2905 
2906 	if (cfg->plen > 128)
2907 		return -EINVAL;
2908 
2909 	/* check the lifetime */
2910 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2911 		return -EINVAL;
2912 
2913 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2914 		return -EINVAL;
2915 
2916 	dev = __dev_get_by_index(net, ifindex);
2917 	if (!dev)
2918 		return -ENODEV;
2919 
2920 	idev = addrconf_add_dev(dev);
2921 	if (IS_ERR(idev))
2922 		return PTR_ERR(idev);
2923 
2924 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2925 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2926 					 true, cfg->pfx, ifindex);
2927 
2928 		if (ret < 0)
2929 			return ret;
2930 	}
2931 
2932 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2933 
2934 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2935 	if (addrconf_finite_timeout(timeout)) {
2936 		expires = jiffies_to_clock_t(timeout * HZ);
2937 		cfg->valid_lft = timeout;
2938 		flags = RTF_EXPIRES;
2939 	} else {
2940 		expires = 0;
2941 		flags = 0;
2942 		cfg->ifa_flags |= IFA_F_PERMANENT;
2943 	}
2944 
2945 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2946 	if (addrconf_finite_timeout(timeout)) {
2947 		if (timeout == 0)
2948 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2949 		cfg->preferred_lft = timeout;
2950 	}
2951 
2952 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2953 	if (!IS_ERR(ifp)) {
2954 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2955 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2956 					      ifp->rt_priority, dev, expires,
2957 					      flags, GFP_KERNEL);
2958 		}
2959 
2960 		/* Send a netlink notification if DAD is enabled and
2961 		 * optimistic flag is not set
2962 		 */
2963 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2964 			ipv6_ifa_notify(0, ifp);
2965 		/*
2966 		 * Note that section 3.1 of RFC 4429 indicates
2967 		 * that the Optimistic flag should not be set for
2968 		 * manually configured addresses
2969 		 */
2970 		addrconf_dad_start(ifp);
2971 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2972 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2973 					 cfg->preferred_lft, true, jiffies);
2974 		in6_ifa_put(ifp);
2975 		addrconf_verify_rtnl();
2976 		return 0;
2977 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2978 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2979 			       cfg->pfx, ifindex);
2980 	}
2981 
2982 	return PTR_ERR(ifp);
2983 }
2984 
2985 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2986 			  const struct in6_addr *pfx, unsigned int plen)
2987 {
2988 	struct inet6_ifaddr *ifp;
2989 	struct inet6_dev *idev;
2990 	struct net_device *dev;
2991 
2992 	if (plen > 128)
2993 		return -EINVAL;
2994 
2995 	dev = __dev_get_by_index(net, ifindex);
2996 	if (!dev)
2997 		return -ENODEV;
2998 
2999 	idev = __in6_dev_get(dev);
3000 	if (!idev)
3001 		return -ENXIO;
3002 
3003 	read_lock_bh(&idev->lock);
3004 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3005 		if (ifp->prefix_len == plen &&
3006 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3007 			in6_ifa_hold(ifp);
3008 			read_unlock_bh(&idev->lock);
3009 
3010 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3011 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3012 				manage_tempaddrs(idev, ifp, 0, 0, false,
3013 						 jiffies);
3014 			ipv6_del_addr(ifp);
3015 			addrconf_verify_rtnl();
3016 			if (ipv6_addr_is_multicast(pfx)) {
3017 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3018 					       false, pfx, dev->ifindex);
3019 			}
3020 			return 0;
3021 		}
3022 	}
3023 	read_unlock_bh(&idev->lock);
3024 	return -EADDRNOTAVAIL;
3025 }
3026 
3027 
3028 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3029 {
3030 	struct ifa6_config cfg = {
3031 		.ifa_flags = IFA_F_PERMANENT,
3032 		.preferred_lft = INFINITY_LIFE_TIME,
3033 		.valid_lft = INFINITY_LIFE_TIME,
3034 	};
3035 	struct in6_ifreq ireq;
3036 	int err;
3037 
3038 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3039 		return -EPERM;
3040 
3041 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3042 		return -EFAULT;
3043 
3044 	cfg.pfx = &ireq.ifr6_addr;
3045 	cfg.plen = ireq.ifr6_prefixlen;
3046 
3047 	rtnl_lock();
3048 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3049 	rtnl_unlock();
3050 	return err;
3051 }
3052 
3053 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3054 {
3055 	struct in6_ifreq ireq;
3056 	int err;
3057 
3058 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3059 		return -EPERM;
3060 
3061 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3062 		return -EFAULT;
3063 
3064 	rtnl_lock();
3065 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3066 			     ireq.ifr6_prefixlen);
3067 	rtnl_unlock();
3068 	return err;
3069 }
3070 
3071 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3072 		     int plen, int scope)
3073 {
3074 	struct inet6_ifaddr *ifp;
3075 	struct ifa6_config cfg = {
3076 		.pfx = addr,
3077 		.plen = plen,
3078 		.ifa_flags = IFA_F_PERMANENT,
3079 		.valid_lft = INFINITY_LIFE_TIME,
3080 		.preferred_lft = INFINITY_LIFE_TIME,
3081 		.scope = scope
3082 	};
3083 
3084 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3085 	if (!IS_ERR(ifp)) {
3086 		spin_lock_bh(&ifp->lock);
3087 		ifp->flags &= ~IFA_F_TENTATIVE;
3088 		spin_unlock_bh(&ifp->lock);
3089 		rt_genid_bump_ipv6(dev_net(idev->dev));
3090 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3091 		in6_ifa_put(ifp);
3092 	}
3093 }
3094 
3095 #if IS_ENABLED(CONFIG_IPV6_SIT)
3096 static void sit_add_v4_addrs(struct inet6_dev *idev)
3097 {
3098 	struct in6_addr addr;
3099 	struct net_device *dev;
3100 	struct net *net = dev_net(idev->dev);
3101 	int scope, plen;
3102 	u32 pflags = 0;
3103 
3104 	ASSERT_RTNL();
3105 
3106 	memset(&addr, 0, sizeof(struct in6_addr));
3107 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3108 
3109 	if (idev->dev->flags&IFF_POINTOPOINT) {
3110 		addr.s6_addr32[0] = htonl(0xfe800000);
3111 		scope = IFA_LINK;
3112 		plen = 64;
3113 	} else {
3114 		scope = IPV6_ADDR_COMPATv4;
3115 		plen = 96;
3116 		pflags |= RTF_NONEXTHOP;
3117 	}
3118 
3119 	if (addr.s6_addr32[3]) {
3120 		add_addr(idev, &addr, plen, scope);
3121 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3122 				      GFP_KERNEL);
3123 		return;
3124 	}
3125 
3126 	for_each_netdev(net, dev) {
3127 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3128 		if (in_dev && (dev->flags & IFF_UP)) {
3129 			struct in_ifaddr *ifa;
3130 
3131 			int flag = scope;
3132 
3133 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3134 
3135 				addr.s6_addr32[3] = ifa->ifa_local;
3136 
3137 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3138 					continue;
3139 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3140 					if (idev->dev->flags&IFF_POINTOPOINT)
3141 						continue;
3142 					flag |= IFA_HOST;
3143 				}
3144 
3145 				add_addr(idev, &addr, plen, flag);
3146 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3147 						      0, pflags, GFP_KERNEL);
3148 			}
3149 		}
3150 	}
3151 }
3152 #endif
3153 
3154 static void init_loopback(struct net_device *dev)
3155 {
3156 	struct inet6_dev  *idev;
3157 
3158 	/* ::1 */
3159 
3160 	ASSERT_RTNL();
3161 
3162 	idev = ipv6_find_idev(dev);
3163 	if (!idev) {
3164 		pr_debug("%s: add_dev failed\n", __func__);
3165 		return;
3166 	}
3167 
3168 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3169 }
3170 
3171 void addrconf_add_linklocal(struct inet6_dev *idev,
3172 			    const struct in6_addr *addr, u32 flags)
3173 {
3174 	struct ifa6_config cfg = {
3175 		.pfx = addr,
3176 		.plen = 64,
3177 		.ifa_flags = flags | IFA_F_PERMANENT,
3178 		.valid_lft = INFINITY_LIFE_TIME,
3179 		.preferred_lft = INFINITY_LIFE_TIME,
3180 		.scope = IFA_LINK
3181 	};
3182 	struct inet6_ifaddr *ifp;
3183 
3184 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3185 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3186 	     idev->cnf.optimistic_dad) &&
3187 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3188 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3189 #endif
3190 
3191 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3192 	if (!IS_ERR(ifp)) {
3193 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3194 				      0, 0, GFP_ATOMIC);
3195 		addrconf_dad_start(ifp);
3196 		in6_ifa_put(ifp);
3197 	}
3198 }
3199 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3200 
3201 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3202 {
3203 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3204 		return true;
3205 
3206 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3207 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3208 		return true;
3209 
3210 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3211 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3212 		return true;
3213 
3214 	return false;
3215 }
3216 
3217 static int ipv6_generate_stable_address(struct in6_addr *address,
3218 					u8 dad_count,
3219 					const struct inet6_dev *idev)
3220 {
3221 	static DEFINE_SPINLOCK(lock);
3222 	static __u32 digest[SHA_DIGEST_WORDS];
3223 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3224 
3225 	static union {
3226 		char __data[SHA_MESSAGE_BYTES];
3227 		struct {
3228 			struct in6_addr secret;
3229 			__be32 prefix[2];
3230 			unsigned char hwaddr[MAX_ADDR_LEN];
3231 			u8 dad_count;
3232 		} __packed;
3233 	} data;
3234 
3235 	struct in6_addr secret;
3236 	struct in6_addr temp;
3237 	struct net *net = dev_net(idev->dev);
3238 
3239 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3240 
3241 	if (idev->cnf.stable_secret.initialized)
3242 		secret = idev->cnf.stable_secret.secret;
3243 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3244 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3245 	else
3246 		return -1;
3247 
3248 retry:
3249 	spin_lock_bh(&lock);
3250 
3251 	sha_init(digest);
3252 	memset(&data, 0, sizeof(data));
3253 	memset(workspace, 0, sizeof(workspace));
3254 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3255 	data.prefix[0] = address->s6_addr32[0];
3256 	data.prefix[1] = address->s6_addr32[1];
3257 	data.secret = secret;
3258 	data.dad_count = dad_count;
3259 
3260 	sha_transform(digest, data.__data, workspace);
3261 
3262 	temp = *address;
3263 	temp.s6_addr32[2] = (__force __be32)digest[0];
3264 	temp.s6_addr32[3] = (__force __be32)digest[1];
3265 
3266 	spin_unlock_bh(&lock);
3267 
3268 	if (ipv6_reserved_interfaceid(temp)) {
3269 		dad_count++;
3270 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3271 			return -1;
3272 		goto retry;
3273 	}
3274 
3275 	*address = temp;
3276 	return 0;
3277 }
3278 
3279 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3280 {
3281 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3282 
3283 	if (s->initialized)
3284 		return;
3285 	s = &idev->cnf.stable_secret;
3286 	get_random_bytes(&s->secret, sizeof(s->secret));
3287 	s->initialized = true;
3288 }
3289 
3290 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3291 {
3292 	struct in6_addr addr;
3293 
3294 	/* no link local addresses on L3 master devices */
3295 	if (netif_is_l3_master(idev->dev))
3296 		return;
3297 
3298 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3299 
3300 	switch (idev->cnf.addr_gen_mode) {
3301 	case IN6_ADDR_GEN_MODE_RANDOM:
3302 		ipv6_gen_mode_random_init(idev);
3303 		/* fallthrough */
3304 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3305 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3306 			addrconf_add_linklocal(idev, &addr,
3307 					       IFA_F_STABLE_PRIVACY);
3308 		else if (prefix_route)
3309 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3310 					      0, 0, GFP_KERNEL);
3311 		break;
3312 	case IN6_ADDR_GEN_MODE_EUI64:
3313 		/* addrconf_add_linklocal also adds a prefix_route and we
3314 		 * only need to care about prefix routes if ipv6_generate_eui64
3315 		 * couldn't generate one.
3316 		 */
3317 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3318 			addrconf_add_linklocal(idev, &addr, 0);
3319 		else if (prefix_route)
3320 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3321 					      0, 0, GFP_KERNEL);
3322 		break;
3323 	case IN6_ADDR_GEN_MODE_NONE:
3324 	default:
3325 		/* will not add any link local address */
3326 		break;
3327 	}
3328 }
3329 
3330 static void addrconf_dev_config(struct net_device *dev)
3331 {
3332 	struct inet6_dev *idev;
3333 
3334 	ASSERT_RTNL();
3335 
3336 	if ((dev->type != ARPHRD_ETHER) &&
3337 	    (dev->type != ARPHRD_FDDI) &&
3338 	    (dev->type != ARPHRD_ARCNET) &&
3339 	    (dev->type != ARPHRD_INFINIBAND) &&
3340 	    (dev->type != ARPHRD_IEEE1394) &&
3341 	    (dev->type != ARPHRD_TUNNEL6) &&
3342 	    (dev->type != ARPHRD_6LOWPAN) &&
3343 	    (dev->type != ARPHRD_IP6GRE) &&
3344 	    (dev->type != ARPHRD_IPGRE) &&
3345 	    (dev->type != ARPHRD_TUNNEL) &&
3346 	    (dev->type != ARPHRD_NONE) &&
3347 	    (dev->type != ARPHRD_RAWIP)) {
3348 		/* Alas, we support only Ethernet autoconfiguration. */
3349 		return;
3350 	}
3351 
3352 	idev = addrconf_add_dev(dev);
3353 	if (IS_ERR(idev))
3354 		return;
3355 
3356 	/* this device type has no EUI support */
3357 	if (dev->type == ARPHRD_NONE &&
3358 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3359 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3360 
3361 	addrconf_addr_gen(idev, false);
3362 }
3363 
3364 #if IS_ENABLED(CONFIG_IPV6_SIT)
3365 static void addrconf_sit_config(struct net_device *dev)
3366 {
3367 	struct inet6_dev *idev;
3368 
3369 	ASSERT_RTNL();
3370 
3371 	/*
3372 	 * Configure the tunnel with one of our IPv4
3373 	 * addresses... we should configure all of
3374 	 * our v4 addrs in the tunnel
3375 	 */
3376 
3377 	idev = ipv6_find_idev(dev);
3378 	if (!idev) {
3379 		pr_debug("%s: add_dev failed\n", __func__);
3380 		return;
3381 	}
3382 
3383 	if (dev->priv_flags & IFF_ISATAP) {
3384 		addrconf_addr_gen(idev, false);
3385 		return;
3386 	}
3387 
3388 	sit_add_v4_addrs(idev);
3389 
3390 	if (dev->flags&IFF_POINTOPOINT)
3391 		addrconf_add_mroute(dev);
3392 }
3393 #endif
3394 
3395 #if IS_ENABLED(CONFIG_NET_IPGRE)
3396 static void addrconf_gre_config(struct net_device *dev)
3397 {
3398 	struct inet6_dev *idev;
3399 
3400 	ASSERT_RTNL();
3401 
3402 	idev = ipv6_find_idev(dev);
3403 	if (!idev) {
3404 		pr_debug("%s: add_dev failed\n", __func__);
3405 		return;
3406 	}
3407 
3408 	addrconf_addr_gen(idev, true);
3409 	if (dev->flags & IFF_POINTOPOINT)
3410 		addrconf_add_mroute(dev);
3411 }
3412 #endif
3413 
3414 static int fixup_permanent_addr(struct net *net,
3415 				struct inet6_dev *idev,
3416 				struct inet6_ifaddr *ifp)
3417 {
3418 	/* !fib6_node means the host route was removed from the
3419 	 * FIB, for example, if 'lo' device is taken down. In that
3420 	 * case regenerate the host route.
3421 	 */
3422 	if (!ifp->rt || !ifp->rt->fib6_node) {
3423 		struct fib6_info *f6i, *prev;
3424 
3425 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3426 					 GFP_ATOMIC);
3427 		if (IS_ERR(f6i))
3428 			return PTR_ERR(f6i);
3429 
3430 		/* ifp->rt can be accessed outside of rtnl */
3431 		spin_lock(&ifp->lock);
3432 		prev = ifp->rt;
3433 		ifp->rt = f6i;
3434 		spin_unlock(&ifp->lock);
3435 
3436 		fib6_info_release(prev);
3437 	}
3438 
3439 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3440 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3441 				      ifp->rt_priority, idev->dev, 0, 0,
3442 				      GFP_ATOMIC);
3443 	}
3444 
3445 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3446 		addrconf_dad_start(ifp);
3447 
3448 	return 0;
3449 }
3450 
3451 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3452 {
3453 	struct inet6_ifaddr *ifp, *tmp;
3454 	struct inet6_dev *idev;
3455 
3456 	idev = __in6_dev_get(dev);
3457 	if (!idev)
3458 		return;
3459 
3460 	write_lock_bh(&idev->lock);
3461 
3462 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3463 		if ((ifp->flags & IFA_F_PERMANENT) &&
3464 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3465 			write_unlock_bh(&idev->lock);
3466 			in6_ifa_hold(ifp);
3467 			ipv6_del_addr(ifp);
3468 			write_lock_bh(&idev->lock);
3469 
3470 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3471 					     idev->dev->name, &ifp->addr);
3472 		}
3473 	}
3474 
3475 	write_unlock_bh(&idev->lock);
3476 }
3477 
3478 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3479 			   void *ptr)
3480 {
3481 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3482 	struct netdev_notifier_change_info *change_info;
3483 	struct netdev_notifier_changeupper_info *info;
3484 	struct inet6_dev *idev = __in6_dev_get(dev);
3485 	struct net *net = dev_net(dev);
3486 	int run_pending = 0;
3487 	int err;
3488 
3489 	switch (event) {
3490 	case NETDEV_REGISTER:
3491 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3492 			idev = ipv6_add_dev(dev);
3493 			if (IS_ERR(idev))
3494 				return notifier_from_errno(PTR_ERR(idev));
3495 		}
3496 		break;
3497 
3498 	case NETDEV_CHANGEMTU:
3499 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3500 		if (dev->mtu < IPV6_MIN_MTU) {
3501 			addrconf_ifdown(dev, dev != net->loopback_dev);
3502 			break;
3503 		}
3504 
3505 		if (idev) {
3506 			rt6_mtu_change(dev, dev->mtu);
3507 			idev->cnf.mtu6 = dev->mtu;
3508 			break;
3509 		}
3510 
3511 		/* allocate new idev */
3512 		idev = ipv6_add_dev(dev);
3513 		if (IS_ERR(idev))
3514 			break;
3515 
3516 		/* device is still not ready */
3517 		if (!(idev->if_flags & IF_READY))
3518 			break;
3519 
3520 		run_pending = 1;
3521 
3522 		/* fall through */
3523 
3524 	case NETDEV_UP:
3525 	case NETDEV_CHANGE:
3526 		if (dev->flags & IFF_SLAVE)
3527 			break;
3528 
3529 		if (idev && idev->cnf.disable_ipv6)
3530 			break;
3531 
3532 		if (event == NETDEV_UP) {
3533 			/* restore routes for permanent addresses */
3534 			addrconf_permanent_addr(net, dev);
3535 
3536 			if (!addrconf_link_ready(dev)) {
3537 				/* device is not ready yet. */
3538 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3539 					 dev->name);
3540 				break;
3541 			}
3542 
3543 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3544 				idev = ipv6_add_dev(dev);
3545 
3546 			if (!IS_ERR_OR_NULL(idev)) {
3547 				idev->if_flags |= IF_READY;
3548 				run_pending = 1;
3549 			}
3550 		} else if (event == NETDEV_CHANGE) {
3551 			if (!addrconf_link_ready(dev)) {
3552 				/* device is still not ready. */
3553 				rt6_sync_down_dev(dev, event);
3554 				break;
3555 			}
3556 
3557 			if (!IS_ERR_OR_NULL(idev)) {
3558 				if (idev->if_flags & IF_READY) {
3559 					/* device is already configured -
3560 					 * but resend MLD reports, we might
3561 					 * have roamed and need to update
3562 					 * multicast snooping switches
3563 					 */
3564 					ipv6_mc_up(idev);
3565 					change_info = ptr;
3566 					if (change_info->flags_changed & IFF_NOARP)
3567 						addrconf_dad_run(idev, true);
3568 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3569 					break;
3570 				}
3571 				idev->if_flags |= IF_READY;
3572 			}
3573 
3574 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3575 				dev->name);
3576 
3577 			run_pending = 1;
3578 		}
3579 
3580 		switch (dev->type) {
3581 #if IS_ENABLED(CONFIG_IPV6_SIT)
3582 		case ARPHRD_SIT:
3583 			addrconf_sit_config(dev);
3584 			break;
3585 #endif
3586 #if IS_ENABLED(CONFIG_NET_IPGRE)
3587 		case ARPHRD_IPGRE:
3588 			addrconf_gre_config(dev);
3589 			break;
3590 #endif
3591 		case ARPHRD_LOOPBACK:
3592 			init_loopback(dev);
3593 			break;
3594 
3595 		default:
3596 			addrconf_dev_config(dev);
3597 			break;
3598 		}
3599 
3600 		if (!IS_ERR_OR_NULL(idev)) {
3601 			if (run_pending)
3602 				addrconf_dad_run(idev, false);
3603 
3604 			/* Device has an address by now */
3605 			rt6_sync_up(dev, RTNH_F_DEAD);
3606 
3607 			/*
3608 			 * If the MTU changed during the interface down,
3609 			 * when the interface up, the changed MTU must be
3610 			 * reflected in the idev as well as routers.
3611 			 */
3612 			if (idev->cnf.mtu6 != dev->mtu &&
3613 			    dev->mtu >= IPV6_MIN_MTU) {
3614 				rt6_mtu_change(dev, dev->mtu);
3615 				idev->cnf.mtu6 = dev->mtu;
3616 			}
3617 			idev->tstamp = jiffies;
3618 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3619 
3620 			/*
3621 			 * If the changed mtu during down is lower than
3622 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3623 			 */
3624 			if (dev->mtu < IPV6_MIN_MTU)
3625 				addrconf_ifdown(dev, dev != net->loopback_dev);
3626 		}
3627 		break;
3628 
3629 	case NETDEV_DOWN:
3630 	case NETDEV_UNREGISTER:
3631 		/*
3632 		 *	Remove all addresses from this interface.
3633 		 */
3634 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3635 		break;
3636 
3637 	case NETDEV_CHANGENAME:
3638 		if (idev) {
3639 			snmp6_unregister_dev(idev);
3640 			addrconf_sysctl_unregister(idev);
3641 			err = addrconf_sysctl_register(idev);
3642 			if (err)
3643 				return notifier_from_errno(err);
3644 			err = snmp6_register_dev(idev);
3645 			if (err) {
3646 				addrconf_sysctl_unregister(idev);
3647 				return notifier_from_errno(err);
3648 			}
3649 		}
3650 		break;
3651 
3652 	case NETDEV_PRE_TYPE_CHANGE:
3653 	case NETDEV_POST_TYPE_CHANGE:
3654 		if (idev)
3655 			addrconf_type_change(dev, event);
3656 		break;
3657 
3658 	case NETDEV_CHANGEUPPER:
3659 		info = ptr;
3660 
3661 		/* flush all routes if dev is linked to or unlinked from
3662 		 * an L3 master device (e.g., VRF)
3663 		 */
3664 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3665 			addrconf_ifdown(dev, 0);
3666 	}
3667 
3668 	return NOTIFY_OK;
3669 }
3670 
3671 /*
3672  *	addrconf module should be notified of a device going up
3673  */
3674 static struct notifier_block ipv6_dev_notf = {
3675 	.notifier_call = addrconf_notify,
3676 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3677 };
3678 
3679 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3680 {
3681 	struct inet6_dev *idev;
3682 	ASSERT_RTNL();
3683 
3684 	idev = __in6_dev_get(dev);
3685 
3686 	if (event == NETDEV_POST_TYPE_CHANGE)
3687 		ipv6_mc_remap(idev);
3688 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3689 		ipv6_mc_unmap(idev);
3690 }
3691 
3692 static bool addr_is_local(const struct in6_addr *addr)
3693 {
3694 	return ipv6_addr_type(addr) &
3695 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3696 }
3697 
3698 static int addrconf_ifdown(struct net_device *dev, int how)
3699 {
3700 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3701 	struct net *net = dev_net(dev);
3702 	struct inet6_dev *idev;
3703 	struct inet6_ifaddr *ifa, *tmp;
3704 	bool keep_addr = false;
3705 	int state, i;
3706 
3707 	ASSERT_RTNL();
3708 
3709 	rt6_disable_ip(dev, event);
3710 
3711 	idev = __in6_dev_get(dev);
3712 	if (!idev)
3713 		return -ENODEV;
3714 
3715 	/*
3716 	 * Step 1: remove reference to ipv6 device from parent device.
3717 	 *	   Do not dev_put!
3718 	 */
3719 	if (how) {
3720 		idev->dead = 1;
3721 
3722 		/* protected by rtnl_lock */
3723 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3724 
3725 		/* Step 1.5: remove snmp6 entry */
3726 		snmp6_unregister_dev(idev);
3727 
3728 	}
3729 
3730 	/* combine the user config with event to determine if permanent
3731 	 * addresses are to be removed from address hash table
3732 	 */
3733 	if (!how && !idev->cnf.disable_ipv6) {
3734 		/* aggregate the system setting and interface setting */
3735 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3736 
3737 		if (!_keep_addr)
3738 			_keep_addr = idev->cnf.keep_addr_on_down;
3739 
3740 		keep_addr = (_keep_addr > 0);
3741 	}
3742 
3743 	/* Step 2: clear hash table */
3744 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3745 		struct hlist_head *h = &inet6_addr_lst[i];
3746 
3747 		spin_lock_bh(&addrconf_hash_lock);
3748 restart:
3749 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3750 			if (ifa->idev == idev) {
3751 				addrconf_del_dad_work(ifa);
3752 				/* combined flag + permanent flag decide if
3753 				 * address is retained on a down event
3754 				 */
3755 				if (!keep_addr ||
3756 				    !(ifa->flags & IFA_F_PERMANENT) ||
3757 				    addr_is_local(&ifa->addr)) {
3758 					hlist_del_init_rcu(&ifa->addr_lst);
3759 					goto restart;
3760 				}
3761 			}
3762 		}
3763 		spin_unlock_bh(&addrconf_hash_lock);
3764 	}
3765 
3766 	write_lock_bh(&idev->lock);
3767 
3768 	addrconf_del_rs_timer(idev);
3769 
3770 	/* Step 2: clear flags for stateless addrconf */
3771 	if (!how)
3772 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3773 
3774 	/* Step 3: clear tempaddr list */
3775 	while (!list_empty(&idev->tempaddr_list)) {
3776 		ifa = list_first_entry(&idev->tempaddr_list,
3777 				       struct inet6_ifaddr, tmp_list);
3778 		list_del(&ifa->tmp_list);
3779 		write_unlock_bh(&idev->lock);
3780 		spin_lock_bh(&ifa->lock);
3781 
3782 		if (ifa->ifpub) {
3783 			in6_ifa_put(ifa->ifpub);
3784 			ifa->ifpub = NULL;
3785 		}
3786 		spin_unlock_bh(&ifa->lock);
3787 		in6_ifa_put(ifa);
3788 		write_lock_bh(&idev->lock);
3789 	}
3790 
3791 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3792 		struct fib6_info *rt = NULL;
3793 		bool keep;
3794 
3795 		addrconf_del_dad_work(ifa);
3796 
3797 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3798 			!addr_is_local(&ifa->addr);
3799 
3800 		write_unlock_bh(&idev->lock);
3801 		spin_lock_bh(&ifa->lock);
3802 
3803 		if (keep) {
3804 			/* set state to skip the notifier below */
3805 			state = INET6_IFADDR_STATE_DEAD;
3806 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3807 			if (!(ifa->flags & IFA_F_NODAD))
3808 				ifa->flags |= IFA_F_TENTATIVE;
3809 
3810 			rt = ifa->rt;
3811 			ifa->rt = NULL;
3812 		} else {
3813 			state = ifa->state;
3814 			ifa->state = INET6_IFADDR_STATE_DEAD;
3815 		}
3816 
3817 		spin_unlock_bh(&ifa->lock);
3818 
3819 		if (rt)
3820 			ip6_del_rt(net, rt);
3821 
3822 		if (state != INET6_IFADDR_STATE_DEAD) {
3823 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3824 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3825 		} else {
3826 			if (idev->cnf.forwarding)
3827 				addrconf_leave_anycast(ifa);
3828 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3829 		}
3830 
3831 		write_lock_bh(&idev->lock);
3832 		if (!keep) {
3833 			list_del_rcu(&ifa->if_list);
3834 			in6_ifa_put(ifa);
3835 		}
3836 	}
3837 
3838 	write_unlock_bh(&idev->lock);
3839 
3840 	/* Step 5: Discard anycast and multicast list */
3841 	if (how) {
3842 		ipv6_ac_destroy_dev(idev);
3843 		ipv6_mc_destroy_dev(idev);
3844 	} else {
3845 		ipv6_mc_down(idev);
3846 	}
3847 
3848 	idev->tstamp = jiffies;
3849 
3850 	/* Last: Shot the device (if unregistered) */
3851 	if (how) {
3852 		addrconf_sysctl_unregister(idev);
3853 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3854 		neigh_ifdown(&nd_tbl, dev);
3855 		in6_dev_put(idev);
3856 	}
3857 	return 0;
3858 }
3859 
3860 static void addrconf_rs_timer(struct timer_list *t)
3861 {
3862 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3863 	struct net_device *dev = idev->dev;
3864 	struct in6_addr lladdr;
3865 
3866 	write_lock(&idev->lock);
3867 	if (idev->dead || !(idev->if_flags & IF_READY))
3868 		goto out;
3869 
3870 	if (!ipv6_accept_ra(idev))
3871 		goto out;
3872 
3873 	/* Announcement received after solicitation was sent */
3874 	if (idev->if_flags & IF_RA_RCVD)
3875 		goto out;
3876 
3877 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3878 		write_unlock(&idev->lock);
3879 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3880 			ndisc_send_rs(dev, &lladdr,
3881 				      &in6addr_linklocal_allrouters);
3882 		else
3883 			goto put;
3884 
3885 		write_lock(&idev->lock);
3886 		idev->rs_interval = rfc3315_s14_backoff_update(
3887 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3888 		/* The wait after the last probe can be shorter */
3889 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3890 					     idev->cnf.rtr_solicits) ?
3891 				      idev->cnf.rtr_solicit_delay :
3892 				      idev->rs_interval);
3893 	} else {
3894 		/*
3895 		 * Note: we do not support deprecated "all on-link"
3896 		 * assumption any longer.
3897 		 */
3898 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3899 	}
3900 
3901 out:
3902 	write_unlock(&idev->lock);
3903 put:
3904 	in6_dev_put(idev);
3905 }
3906 
3907 /*
3908  *	Duplicate Address Detection
3909  */
3910 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3911 {
3912 	unsigned long rand_num;
3913 	struct inet6_dev *idev = ifp->idev;
3914 	u64 nonce;
3915 
3916 	if (ifp->flags & IFA_F_OPTIMISTIC)
3917 		rand_num = 0;
3918 	else
3919 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3920 
3921 	nonce = 0;
3922 	if (idev->cnf.enhanced_dad ||
3923 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3924 		do
3925 			get_random_bytes(&nonce, 6);
3926 		while (nonce == 0);
3927 	}
3928 	ifp->dad_nonce = nonce;
3929 	ifp->dad_probes = idev->cnf.dad_transmits;
3930 	addrconf_mod_dad_work(ifp, rand_num);
3931 }
3932 
3933 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3934 {
3935 	struct inet6_dev *idev = ifp->idev;
3936 	struct net_device *dev = idev->dev;
3937 	bool bump_id, notify = false;
3938 	struct net *net;
3939 
3940 	addrconf_join_solict(dev, &ifp->addr);
3941 
3942 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3943 
3944 	read_lock_bh(&idev->lock);
3945 	spin_lock(&ifp->lock);
3946 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3947 		goto out;
3948 
3949 	net = dev_net(dev);
3950 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3951 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3952 	     idev->cnf.accept_dad < 1) ||
3953 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3954 	    ifp->flags & IFA_F_NODAD) {
3955 		bool send_na = false;
3956 
3957 		if (ifp->flags & IFA_F_TENTATIVE &&
3958 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3959 			send_na = true;
3960 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3961 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3962 		spin_unlock(&ifp->lock);
3963 		read_unlock_bh(&idev->lock);
3964 
3965 		addrconf_dad_completed(ifp, bump_id, send_na);
3966 		return;
3967 	}
3968 
3969 	if (!(idev->if_flags & IF_READY)) {
3970 		spin_unlock(&ifp->lock);
3971 		read_unlock_bh(&idev->lock);
3972 		/*
3973 		 * If the device is not ready:
3974 		 * - keep it tentative if it is a permanent address.
3975 		 * - otherwise, kill it.
3976 		 */
3977 		in6_ifa_hold(ifp);
3978 		addrconf_dad_stop(ifp, 0);
3979 		return;
3980 	}
3981 
3982 	/*
3983 	 * Optimistic nodes can start receiving
3984 	 * Frames right away
3985 	 */
3986 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3987 		ip6_ins_rt(net, ifp->rt);
3988 		if (ipv6_use_optimistic_addr(net, idev)) {
3989 			/* Because optimistic nodes can use this address,
3990 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3991 			 */
3992 			notify = true;
3993 		}
3994 	}
3995 
3996 	addrconf_dad_kick(ifp);
3997 out:
3998 	spin_unlock(&ifp->lock);
3999 	read_unlock_bh(&idev->lock);
4000 	if (notify)
4001 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4002 }
4003 
4004 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4005 {
4006 	bool begin_dad = false;
4007 
4008 	spin_lock_bh(&ifp->lock);
4009 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4010 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4011 		begin_dad = true;
4012 	}
4013 	spin_unlock_bh(&ifp->lock);
4014 
4015 	if (begin_dad)
4016 		addrconf_mod_dad_work(ifp, 0);
4017 }
4018 
4019 static void addrconf_dad_work(struct work_struct *w)
4020 {
4021 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4022 						struct inet6_ifaddr,
4023 						dad_work);
4024 	struct inet6_dev *idev = ifp->idev;
4025 	bool bump_id, disable_ipv6 = false;
4026 	struct in6_addr mcaddr;
4027 
4028 	enum {
4029 		DAD_PROCESS,
4030 		DAD_BEGIN,
4031 		DAD_ABORT,
4032 	} action = DAD_PROCESS;
4033 
4034 	rtnl_lock();
4035 
4036 	spin_lock_bh(&ifp->lock);
4037 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4038 		action = DAD_BEGIN;
4039 		ifp->state = INET6_IFADDR_STATE_DAD;
4040 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4041 		action = DAD_ABORT;
4042 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4043 
4044 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4045 		     idev->cnf.accept_dad > 1) &&
4046 		    !idev->cnf.disable_ipv6 &&
4047 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4048 			struct in6_addr addr;
4049 
4050 			addr.s6_addr32[0] = htonl(0xfe800000);
4051 			addr.s6_addr32[1] = 0;
4052 
4053 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4054 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4055 				/* DAD failed for link-local based on MAC */
4056 				idev->cnf.disable_ipv6 = 1;
4057 
4058 				pr_info("%s: IPv6 being disabled!\n",
4059 					ifp->idev->dev->name);
4060 				disable_ipv6 = true;
4061 			}
4062 		}
4063 	}
4064 	spin_unlock_bh(&ifp->lock);
4065 
4066 	if (action == DAD_BEGIN) {
4067 		addrconf_dad_begin(ifp);
4068 		goto out;
4069 	} else if (action == DAD_ABORT) {
4070 		in6_ifa_hold(ifp);
4071 		addrconf_dad_stop(ifp, 1);
4072 		if (disable_ipv6)
4073 			addrconf_ifdown(idev->dev, 0);
4074 		goto out;
4075 	}
4076 
4077 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4078 		goto out;
4079 
4080 	write_lock_bh(&idev->lock);
4081 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4082 		write_unlock_bh(&idev->lock);
4083 		goto out;
4084 	}
4085 
4086 	spin_lock(&ifp->lock);
4087 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4088 		spin_unlock(&ifp->lock);
4089 		write_unlock_bh(&idev->lock);
4090 		goto out;
4091 	}
4092 
4093 	if (ifp->dad_probes == 0) {
4094 		bool send_na = false;
4095 
4096 		/*
4097 		 * DAD was successful
4098 		 */
4099 
4100 		if (ifp->flags & IFA_F_TENTATIVE &&
4101 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4102 			send_na = true;
4103 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4104 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4105 		spin_unlock(&ifp->lock);
4106 		write_unlock_bh(&idev->lock);
4107 
4108 		addrconf_dad_completed(ifp, bump_id, send_na);
4109 
4110 		goto out;
4111 	}
4112 
4113 	ifp->dad_probes--;
4114 	addrconf_mod_dad_work(ifp,
4115 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4116 	spin_unlock(&ifp->lock);
4117 	write_unlock_bh(&idev->lock);
4118 
4119 	/* send a neighbour solicitation for our addr */
4120 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4121 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4122 		      ifp->dad_nonce);
4123 out:
4124 	in6_ifa_put(ifp);
4125 	rtnl_unlock();
4126 }
4127 
4128 /* ifp->idev must be at least read locked */
4129 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4130 {
4131 	struct inet6_ifaddr *ifpiter;
4132 	struct inet6_dev *idev = ifp->idev;
4133 
4134 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4135 		if (ifpiter->scope > IFA_LINK)
4136 			break;
4137 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4138 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4139 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4140 		    IFA_F_PERMANENT)
4141 			return false;
4142 	}
4143 	return true;
4144 }
4145 
4146 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4147 				   bool send_na)
4148 {
4149 	struct net_device *dev = ifp->idev->dev;
4150 	struct in6_addr lladdr;
4151 	bool send_rs, send_mld;
4152 
4153 	addrconf_del_dad_work(ifp);
4154 
4155 	/*
4156 	 *	Configure the address for reception. Now it is valid.
4157 	 */
4158 
4159 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4160 
4161 	/* If added prefix is link local and we are prepared to process
4162 	   router advertisements, start sending router solicitations.
4163 	 */
4164 
4165 	read_lock_bh(&ifp->idev->lock);
4166 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4167 	send_rs = send_mld &&
4168 		  ipv6_accept_ra(ifp->idev) &&
4169 		  ifp->idev->cnf.rtr_solicits != 0 &&
4170 		  (dev->flags&IFF_LOOPBACK) == 0;
4171 	read_unlock_bh(&ifp->idev->lock);
4172 
4173 	/* While dad is in progress mld report's source address is in6_addrany.
4174 	 * Resend with proper ll now.
4175 	 */
4176 	if (send_mld)
4177 		ipv6_mc_dad_complete(ifp->idev);
4178 
4179 	/* send unsolicited NA if enabled */
4180 	if (send_na &&
4181 	    (ifp->idev->cnf.ndisc_notify ||
4182 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4183 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4184 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4185 			      /*solicited=*/ false, /*override=*/ true,
4186 			      /*inc_opt=*/ true);
4187 	}
4188 
4189 	if (send_rs) {
4190 		/*
4191 		 *	If a host as already performed a random delay
4192 		 *	[...] as part of DAD [...] there is no need
4193 		 *	to delay again before sending the first RS
4194 		 */
4195 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4196 			return;
4197 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4198 
4199 		write_lock_bh(&ifp->idev->lock);
4200 		spin_lock(&ifp->lock);
4201 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4202 			ifp->idev->cnf.rtr_solicit_interval);
4203 		ifp->idev->rs_probes = 1;
4204 		ifp->idev->if_flags |= IF_RS_SENT;
4205 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4206 		spin_unlock(&ifp->lock);
4207 		write_unlock_bh(&ifp->idev->lock);
4208 	}
4209 
4210 	if (bump_id)
4211 		rt_genid_bump_ipv6(dev_net(dev));
4212 
4213 	/* Make sure that a new temporary address will be created
4214 	 * before this temporary address becomes deprecated.
4215 	 */
4216 	if (ifp->flags & IFA_F_TEMPORARY)
4217 		addrconf_verify_rtnl();
4218 }
4219 
4220 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4221 {
4222 	struct inet6_ifaddr *ifp;
4223 
4224 	read_lock_bh(&idev->lock);
4225 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4226 		spin_lock(&ifp->lock);
4227 		if ((ifp->flags & IFA_F_TENTATIVE &&
4228 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4229 			if (restart)
4230 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4231 			addrconf_dad_kick(ifp);
4232 		}
4233 		spin_unlock(&ifp->lock);
4234 	}
4235 	read_unlock_bh(&idev->lock);
4236 }
4237 
4238 #ifdef CONFIG_PROC_FS
4239 struct if6_iter_state {
4240 	struct seq_net_private p;
4241 	int bucket;
4242 	int offset;
4243 };
4244 
4245 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4246 {
4247 	struct if6_iter_state *state = seq->private;
4248 	struct net *net = seq_file_net(seq);
4249 	struct inet6_ifaddr *ifa = NULL;
4250 	int p = 0;
4251 
4252 	/* initial bucket if pos is 0 */
4253 	if (pos == 0) {
4254 		state->bucket = 0;
4255 		state->offset = 0;
4256 	}
4257 
4258 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4259 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4260 					 addr_lst) {
4261 			if (!net_eq(dev_net(ifa->idev->dev), net))
4262 				continue;
4263 			/* sync with offset */
4264 			if (p < state->offset) {
4265 				p++;
4266 				continue;
4267 			}
4268 			return ifa;
4269 		}
4270 
4271 		/* prepare for next bucket */
4272 		state->offset = 0;
4273 		p = 0;
4274 	}
4275 	return NULL;
4276 }
4277 
4278 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4279 					 struct inet6_ifaddr *ifa)
4280 {
4281 	struct if6_iter_state *state = seq->private;
4282 	struct net *net = seq_file_net(seq);
4283 
4284 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4285 		if (!net_eq(dev_net(ifa->idev->dev), net))
4286 			continue;
4287 		state->offset++;
4288 		return ifa;
4289 	}
4290 
4291 	state->offset = 0;
4292 	while (++state->bucket < IN6_ADDR_HSIZE) {
4293 		hlist_for_each_entry_rcu(ifa,
4294 				     &inet6_addr_lst[state->bucket], addr_lst) {
4295 			if (!net_eq(dev_net(ifa->idev->dev), net))
4296 				continue;
4297 			return ifa;
4298 		}
4299 	}
4300 
4301 	return NULL;
4302 }
4303 
4304 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4305 	__acquires(rcu)
4306 {
4307 	rcu_read_lock();
4308 	return if6_get_first(seq, *pos);
4309 }
4310 
4311 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4312 {
4313 	struct inet6_ifaddr *ifa;
4314 
4315 	ifa = if6_get_next(seq, v);
4316 	++*pos;
4317 	return ifa;
4318 }
4319 
4320 static void if6_seq_stop(struct seq_file *seq, void *v)
4321 	__releases(rcu)
4322 {
4323 	rcu_read_unlock();
4324 }
4325 
4326 static int if6_seq_show(struct seq_file *seq, void *v)
4327 {
4328 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4329 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4330 		   &ifp->addr,
4331 		   ifp->idev->dev->ifindex,
4332 		   ifp->prefix_len,
4333 		   ifp->scope,
4334 		   (u8) ifp->flags,
4335 		   ifp->idev->dev->name);
4336 	return 0;
4337 }
4338 
4339 static const struct seq_operations if6_seq_ops = {
4340 	.start	= if6_seq_start,
4341 	.next	= if6_seq_next,
4342 	.show	= if6_seq_show,
4343 	.stop	= if6_seq_stop,
4344 };
4345 
4346 static int __net_init if6_proc_net_init(struct net *net)
4347 {
4348 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4349 			sizeof(struct if6_iter_state)))
4350 		return -ENOMEM;
4351 	return 0;
4352 }
4353 
4354 static void __net_exit if6_proc_net_exit(struct net *net)
4355 {
4356 	remove_proc_entry("if_inet6", net->proc_net);
4357 }
4358 
4359 static struct pernet_operations if6_proc_net_ops = {
4360 	.init = if6_proc_net_init,
4361 	.exit = if6_proc_net_exit,
4362 };
4363 
4364 int __init if6_proc_init(void)
4365 {
4366 	return register_pernet_subsys(&if6_proc_net_ops);
4367 }
4368 
4369 void if6_proc_exit(void)
4370 {
4371 	unregister_pernet_subsys(&if6_proc_net_ops);
4372 }
4373 #endif	/* CONFIG_PROC_FS */
4374 
4375 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4376 /* Check if address is a home address configured on any interface. */
4377 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4378 {
4379 	unsigned int hash = inet6_addr_hash(net, addr);
4380 	struct inet6_ifaddr *ifp = NULL;
4381 	int ret = 0;
4382 
4383 	rcu_read_lock();
4384 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4385 		if (!net_eq(dev_net(ifp->idev->dev), net))
4386 			continue;
4387 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4388 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4389 			ret = 1;
4390 			break;
4391 		}
4392 	}
4393 	rcu_read_unlock();
4394 	return ret;
4395 }
4396 #endif
4397 
4398 /*
4399  *	Periodic address status verification
4400  */
4401 
4402 static void addrconf_verify_rtnl(void)
4403 {
4404 	unsigned long now, next, next_sec, next_sched;
4405 	struct inet6_ifaddr *ifp;
4406 	int i;
4407 
4408 	ASSERT_RTNL();
4409 
4410 	rcu_read_lock_bh();
4411 	now = jiffies;
4412 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4413 
4414 	cancel_delayed_work(&addr_chk_work);
4415 
4416 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4417 restart:
4418 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4419 			unsigned long age;
4420 
4421 			/* When setting preferred_lft to a value not zero or
4422 			 * infinity, while valid_lft is infinity
4423 			 * IFA_F_PERMANENT has a non-infinity life time.
4424 			 */
4425 			if ((ifp->flags & IFA_F_PERMANENT) &&
4426 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4427 				continue;
4428 
4429 			spin_lock(&ifp->lock);
4430 			/* We try to batch several events at once. */
4431 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4432 
4433 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4434 			    age >= ifp->valid_lft) {
4435 				spin_unlock(&ifp->lock);
4436 				in6_ifa_hold(ifp);
4437 				ipv6_del_addr(ifp);
4438 				goto restart;
4439 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4440 				spin_unlock(&ifp->lock);
4441 				continue;
4442 			} else if (age >= ifp->prefered_lft) {
4443 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4444 				int deprecate = 0;
4445 
4446 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4447 					deprecate = 1;
4448 					ifp->flags |= IFA_F_DEPRECATED;
4449 				}
4450 
4451 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4452 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4453 					next = ifp->tstamp + ifp->valid_lft * HZ;
4454 
4455 				spin_unlock(&ifp->lock);
4456 
4457 				if (deprecate) {
4458 					in6_ifa_hold(ifp);
4459 
4460 					ipv6_ifa_notify(0, ifp);
4461 					in6_ifa_put(ifp);
4462 					goto restart;
4463 				}
4464 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4465 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4466 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4467 					ifp->idev->cnf.dad_transmits *
4468 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4469 
4470 				if (age >= ifp->prefered_lft - regen_advance) {
4471 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4472 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4473 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4474 					if (!ifp->regen_count && ifpub) {
4475 						ifp->regen_count++;
4476 						in6_ifa_hold(ifp);
4477 						in6_ifa_hold(ifpub);
4478 						spin_unlock(&ifp->lock);
4479 
4480 						spin_lock(&ifpub->lock);
4481 						ifpub->regen_count = 0;
4482 						spin_unlock(&ifpub->lock);
4483 						rcu_read_unlock_bh();
4484 						ipv6_create_tempaddr(ifpub, ifp, true);
4485 						in6_ifa_put(ifpub);
4486 						in6_ifa_put(ifp);
4487 						rcu_read_lock_bh();
4488 						goto restart;
4489 					}
4490 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4491 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4492 				spin_unlock(&ifp->lock);
4493 			} else {
4494 				/* ifp->prefered_lft <= ifp->valid_lft */
4495 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4496 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4497 				spin_unlock(&ifp->lock);
4498 			}
4499 		}
4500 	}
4501 
4502 	next_sec = round_jiffies_up(next);
4503 	next_sched = next;
4504 
4505 	/* If rounded timeout is accurate enough, accept it. */
4506 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4507 		next_sched = next_sec;
4508 
4509 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4510 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4511 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4512 
4513 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4514 		 now, next, next_sec, next_sched);
4515 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4516 	rcu_read_unlock_bh();
4517 }
4518 
4519 static void addrconf_verify_work(struct work_struct *w)
4520 {
4521 	rtnl_lock();
4522 	addrconf_verify_rtnl();
4523 	rtnl_unlock();
4524 }
4525 
4526 static void addrconf_verify(void)
4527 {
4528 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4529 }
4530 
4531 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4532 				     struct in6_addr **peer_pfx)
4533 {
4534 	struct in6_addr *pfx = NULL;
4535 
4536 	*peer_pfx = NULL;
4537 
4538 	if (addr)
4539 		pfx = nla_data(addr);
4540 
4541 	if (local) {
4542 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4543 			*peer_pfx = pfx;
4544 		pfx = nla_data(local);
4545 	}
4546 
4547 	return pfx;
4548 }
4549 
4550 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4551 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4552 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4553 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4554 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4555 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4556 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4557 };
4558 
4559 static int
4560 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4561 		  struct netlink_ext_ack *extack)
4562 {
4563 	struct net *net = sock_net(skb->sk);
4564 	struct ifaddrmsg *ifm;
4565 	struct nlattr *tb[IFA_MAX+1];
4566 	struct in6_addr *pfx, *peer_pfx;
4567 	u32 ifa_flags;
4568 	int err;
4569 
4570 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4571 				     ifa_ipv6_policy, extack);
4572 	if (err < 0)
4573 		return err;
4574 
4575 	ifm = nlmsg_data(nlh);
4576 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4577 	if (!pfx)
4578 		return -EINVAL;
4579 
4580 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4581 
4582 	/* We ignore other flags so far. */
4583 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4584 
4585 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4586 			      ifm->ifa_prefixlen);
4587 }
4588 
4589 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4590 			       unsigned long expires, u32 flags)
4591 {
4592 	struct fib6_info *f6i;
4593 	u32 prio;
4594 
4595 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
4596 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4597 	if (!f6i)
4598 		return -ENOENT;
4599 
4600 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4601 	if (f6i->fib6_metric != prio) {
4602 		/* delete old one */
4603 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4604 
4605 		/* add new one */
4606 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4607 				      ifp->rt_priority, ifp->idev->dev,
4608 				      expires, flags, GFP_KERNEL);
4609 	} else {
4610 		if (!expires)
4611 			fib6_clean_expires(f6i);
4612 		else
4613 			fib6_set_expires(f6i, expires);
4614 
4615 		fib6_info_release(f6i);
4616 	}
4617 
4618 	return 0;
4619 }
4620 
4621 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4622 {
4623 	u32 flags;
4624 	clock_t expires;
4625 	unsigned long timeout;
4626 	bool was_managetempaddr;
4627 	bool had_prefixroute;
4628 
4629 	ASSERT_RTNL();
4630 
4631 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4632 		return -EINVAL;
4633 
4634 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4635 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4636 		return -EINVAL;
4637 
4638 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4639 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4640 
4641 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4642 	if (addrconf_finite_timeout(timeout)) {
4643 		expires = jiffies_to_clock_t(timeout * HZ);
4644 		cfg->valid_lft = timeout;
4645 		flags = RTF_EXPIRES;
4646 	} else {
4647 		expires = 0;
4648 		flags = 0;
4649 		cfg->ifa_flags |= IFA_F_PERMANENT;
4650 	}
4651 
4652 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4653 	if (addrconf_finite_timeout(timeout)) {
4654 		if (timeout == 0)
4655 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4656 		cfg->preferred_lft = timeout;
4657 	}
4658 
4659 	spin_lock_bh(&ifp->lock);
4660 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4661 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4662 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4663 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4664 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4665 			IFA_F_NOPREFIXROUTE);
4666 	ifp->flags |= cfg->ifa_flags;
4667 	ifp->tstamp = jiffies;
4668 	ifp->valid_lft = cfg->valid_lft;
4669 	ifp->prefered_lft = cfg->preferred_lft;
4670 
4671 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4672 		ifp->rt_priority = cfg->rt_priority;
4673 
4674 	spin_unlock_bh(&ifp->lock);
4675 	if (!(ifp->flags&IFA_F_TENTATIVE))
4676 		ipv6_ifa_notify(0, ifp);
4677 
4678 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4679 		int rc = -ENOENT;
4680 
4681 		if (had_prefixroute)
4682 			rc = modify_prefix_route(ifp, expires, flags);
4683 
4684 		/* prefix route could have been deleted; if so restore it */
4685 		if (rc == -ENOENT) {
4686 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4687 					      ifp->rt_priority, ifp->idev->dev,
4688 					      expires, flags, GFP_KERNEL);
4689 		}
4690 	} else if (had_prefixroute) {
4691 		enum cleanup_prefix_rt_t action;
4692 		unsigned long rt_expires;
4693 
4694 		write_lock_bh(&ifp->idev->lock);
4695 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4696 		write_unlock_bh(&ifp->idev->lock);
4697 
4698 		if (action != CLEANUP_PREFIX_RT_NOP) {
4699 			cleanup_prefix_route(ifp, rt_expires,
4700 				action == CLEANUP_PREFIX_RT_DEL);
4701 		}
4702 	}
4703 
4704 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4705 		if (was_managetempaddr &&
4706 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4707 			cfg->valid_lft = 0;
4708 			cfg->preferred_lft = 0;
4709 		}
4710 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4711 				 cfg->preferred_lft, !was_managetempaddr,
4712 				 jiffies);
4713 	}
4714 
4715 	addrconf_verify_rtnl();
4716 
4717 	return 0;
4718 }
4719 
4720 static int
4721 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4722 		  struct netlink_ext_ack *extack)
4723 {
4724 	struct net *net = sock_net(skb->sk);
4725 	struct ifaddrmsg *ifm;
4726 	struct nlattr *tb[IFA_MAX+1];
4727 	struct in6_addr *peer_pfx;
4728 	struct inet6_ifaddr *ifa;
4729 	struct net_device *dev;
4730 	struct inet6_dev *idev;
4731 	struct ifa6_config cfg;
4732 	int err;
4733 
4734 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4735 				     ifa_ipv6_policy, extack);
4736 	if (err < 0)
4737 		return err;
4738 
4739 	memset(&cfg, 0, sizeof(cfg));
4740 
4741 	ifm = nlmsg_data(nlh);
4742 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4743 	if (!cfg.pfx)
4744 		return -EINVAL;
4745 
4746 	cfg.peer_pfx = peer_pfx;
4747 	cfg.plen = ifm->ifa_prefixlen;
4748 	if (tb[IFA_RT_PRIORITY])
4749 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4750 
4751 	cfg.valid_lft = INFINITY_LIFE_TIME;
4752 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4753 
4754 	if (tb[IFA_CACHEINFO]) {
4755 		struct ifa_cacheinfo *ci;
4756 
4757 		ci = nla_data(tb[IFA_CACHEINFO]);
4758 		cfg.valid_lft = ci->ifa_valid;
4759 		cfg.preferred_lft = ci->ifa_prefered;
4760 	}
4761 
4762 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4763 	if (!dev)
4764 		return -ENODEV;
4765 
4766 	if (tb[IFA_FLAGS])
4767 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4768 	else
4769 		cfg.ifa_flags = ifm->ifa_flags;
4770 
4771 	/* We ignore other flags so far. */
4772 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4773 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4774 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4775 
4776 	idev = ipv6_find_idev(dev);
4777 	if (!idev)
4778 		return -ENOBUFS;
4779 
4780 	if (!ipv6_allow_optimistic_dad(net, idev))
4781 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4782 
4783 	if (cfg.ifa_flags & IFA_F_NODAD &&
4784 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4785 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4786 		return -EINVAL;
4787 	}
4788 
4789 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4790 	if (!ifa) {
4791 		/*
4792 		 * It would be best to check for !NLM_F_CREATE here but
4793 		 * userspace already relies on not having to provide this.
4794 		 */
4795 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4796 	}
4797 
4798 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4799 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4800 		err = -EEXIST;
4801 	else
4802 		err = inet6_addr_modify(ifa, &cfg);
4803 
4804 	in6_ifa_put(ifa);
4805 
4806 	return err;
4807 }
4808 
4809 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4810 			  u8 scope, int ifindex)
4811 {
4812 	struct ifaddrmsg *ifm;
4813 
4814 	ifm = nlmsg_data(nlh);
4815 	ifm->ifa_family = AF_INET6;
4816 	ifm->ifa_prefixlen = prefixlen;
4817 	ifm->ifa_flags = flags;
4818 	ifm->ifa_scope = scope;
4819 	ifm->ifa_index = ifindex;
4820 }
4821 
4822 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4823 			 unsigned long tstamp, u32 preferred, u32 valid)
4824 {
4825 	struct ifa_cacheinfo ci;
4826 
4827 	ci.cstamp = cstamp_delta(cstamp);
4828 	ci.tstamp = cstamp_delta(tstamp);
4829 	ci.ifa_prefered = preferred;
4830 	ci.ifa_valid = valid;
4831 
4832 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4833 }
4834 
4835 static inline int rt_scope(int ifa_scope)
4836 {
4837 	if (ifa_scope & IFA_HOST)
4838 		return RT_SCOPE_HOST;
4839 	else if (ifa_scope & IFA_LINK)
4840 		return RT_SCOPE_LINK;
4841 	else if (ifa_scope & IFA_SITE)
4842 		return RT_SCOPE_SITE;
4843 	else
4844 		return RT_SCOPE_UNIVERSE;
4845 }
4846 
4847 static inline int inet6_ifaddr_msgsize(void)
4848 {
4849 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4850 	       + nla_total_size(16) /* IFA_LOCAL */
4851 	       + nla_total_size(16) /* IFA_ADDRESS */
4852 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4853 	       + nla_total_size(4)  /* IFA_FLAGS */
4854 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4855 }
4856 
4857 enum addr_type_t {
4858 	UNICAST_ADDR,
4859 	MULTICAST_ADDR,
4860 	ANYCAST_ADDR,
4861 };
4862 
4863 struct inet6_fill_args {
4864 	u32 portid;
4865 	u32 seq;
4866 	int event;
4867 	unsigned int flags;
4868 	int netnsid;
4869 	int ifindex;
4870 	enum addr_type_t type;
4871 };
4872 
4873 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4874 			     struct inet6_fill_args *args)
4875 {
4876 	struct nlmsghdr  *nlh;
4877 	u32 preferred, valid;
4878 
4879 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4880 			sizeof(struct ifaddrmsg), args->flags);
4881 	if (!nlh)
4882 		return -EMSGSIZE;
4883 
4884 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4885 		      ifa->idev->dev->ifindex);
4886 
4887 	if (args->netnsid >= 0 &&
4888 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4889 		goto error;
4890 
4891 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4892 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4893 		preferred = ifa->prefered_lft;
4894 		valid = ifa->valid_lft;
4895 		if (preferred != INFINITY_LIFE_TIME) {
4896 			long tval = (jiffies - ifa->tstamp)/HZ;
4897 			if (preferred > tval)
4898 				preferred -= tval;
4899 			else
4900 				preferred = 0;
4901 			if (valid != INFINITY_LIFE_TIME) {
4902 				if (valid > tval)
4903 					valid -= tval;
4904 				else
4905 					valid = 0;
4906 			}
4907 		}
4908 	} else {
4909 		preferred = INFINITY_LIFE_TIME;
4910 		valid = INFINITY_LIFE_TIME;
4911 	}
4912 
4913 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4914 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4915 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4916 			goto error;
4917 	} else
4918 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4919 			goto error;
4920 
4921 	if (ifa->rt_priority &&
4922 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4923 		goto error;
4924 
4925 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4926 		goto error;
4927 
4928 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4929 		goto error;
4930 
4931 	nlmsg_end(skb, nlh);
4932 	return 0;
4933 
4934 error:
4935 	nlmsg_cancel(skb, nlh);
4936 	return -EMSGSIZE;
4937 }
4938 
4939 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4940 			       struct inet6_fill_args *args)
4941 {
4942 	struct nlmsghdr  *nlh;
4943 	u8 scope = RT_SCOPE_UNIVERSE;
4944 	int ifindex = ifmca->idev->dev->ifindex;
4945 
4946 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4947 		scope = RT_SCOPE_SITE;
4948 
4949 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4950 			sizeof(struct ifaddrmsg), args->flags);
4951 	if (!nlh)
4952 		return -EMSGSIZE;
4953 
4954 	if (args->netnsid >= 0 &&
4955 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4956 		return -EMSGSIZE;
4957 
4958 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4959 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4960 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4961 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4962 		nlmsg_cancel(skb, nlh);
4963 		return -EMSGSIZE;
4964 	}
4965 
4966 	nlmsg_end(skb, nlh);
4967 	return 0;
4968 }
4969 
4970 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4971 			       struct inet6_fill_args *args)
4972 {
4973 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4974 	int ifindex = dev ? dev->ifindex : 1;
4975 	struct nlmsghdr  *nlh;
4976 	u8 scope = RT_SCOPE_UNIVERSE;
4977 
4978 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4979 		scope = RT_SCOPE_SITE;
4980 
4981 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4982 			sizeof(struct ifaddrmsg), args->flags);
4983 	if (!nlh)
4984 		return -EMSGSIZE;
4985 
4986 	if (args->netnsid >= 0 &&
4987 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4988 		return -EMSGSIZE;
4989 
4990 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4991 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4992 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4993 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4994 		nlmsg_cancel(skb, nlh);
4995 		return -EMSGSIZE;
4996 	}
4997 
4998 	nlmsg_end(skb, nlh);
4999 	return 0;
5000 }
5001 
5002 /* called with rcu_read_lock() */
5003 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5004 			  struct netlink_callback *cb, int s_ip_idx,
5005 			  struct inet6_fill_args *fillargs)
5006 {
5007 	struct ifmcaddr6 *ifmca;
5008 	struct ifacaddr6 *ifaca;
5009 	int ip_idx = 0;
5010 	int err = 1;
5011 
5012 	read_lock_bh(&idev->lock);
5013 	switch (fillargs->type) {
5014 	case UNICAST_ADDR: {
5015 		struct inet6_ifaddr *ifa;
5016 		fillargs->event = RTM_NEWADDR;
5017 
5018 		/* unicast address incl. temp addr */
5019 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5020 			if (ip_idx < s_ip_idx)
5021 				goto next;
5022 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5023 			if (err < 0)
5024 				break;
5025 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5026 next:
5027 			ip_idx++;
5028 		}
5029 		break;
5030 	}
5031 	case MULTICAST_ADDR:
5032 		fillargs->event = RTM_GETMULTICAST;
5033 
5034 		/* multicast address */
5035 		for (ifmca = idev->mc_list; ifmca;
5036 		     ifmca = ifmca->next, ip_idx++) {
5037 			if (ip_idx < s_ip_idx)
5038 				continue;
5039 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5040 			if (err < 0)
5041 				break;
5042 		}
5043 		break;
5044 	case ANYCAST_ADDR:
5045 		fillargs->event = RTM_GETANYCAST;
5046 		/* anycast address */
5047 		for (ifaca = idev->ac_list; ifaca;
5048 		     ifaca = ifaca->aca_next, ip_idx++) {
5049 			if (ip_idx < s_ip_idx)
5050 				continue;
5051 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5052 			if (err < 0)
5053 				break;
5054 		}
5055 		break;
5056 	default:
5057 		break;
5058 	}
5059 	read_unlock_bh(&idev->lock);
5060 	cb->args[2] = ip_idx;
5061 	return err;
5062 }
5063 
5064 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5065 				       struct inet6_fill_args *fillargs,
5066 				       struct net **tgt_net, struct sock *sk,
5067 				       struct netlink_callback *cb)
5068 {
5069 	struct netlink_ext_ack *extack = cb->extack;
5070 	struct nlattr *tb[IFA_MAX+1];
5071 	struct ifaddrmsg *ifm;
5072 	int err, i;
5073 
5074 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5075 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5076 		return -EINVAL;
5077 	}
5078 
5079 	ifm = nlmsg_data(nlh);
5080 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5081 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5082 		return -EINVAL;
5083 	}
5084 
5085 	fillargs->ifindex = ifm->ifa_index;
5086 	if (fillargs->ifindex) {
5087 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5088 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5089 	}
5090 
5091 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5092 					    ifa_ipv6_policy, extack);
5093 	if (err < 0)
5094 		return err;
5095 
5096 	for (i = 0; i <= IFA_MAX; ++i) {
5097 		if (!tb[i])
5098 			continue;
5099 
5100 		if (i == IFA_TARGET_NETNSID) {
5101 			struct net *net;
5102 
5103 			fillargs->netnsid = nla_get_s32(tb[i]);
5104 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5105 			if (IS_ERR(net)) {
5106 				fillargs->netnsid = -1;
5107 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5108 				return PTR_ERR(net);
5109 			}
5110 			*tgt_net = net;
5111 		} else {
5112 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5113 			return -EINVAL;
5114 		}
5115 	}
5116 
5117 	return 0;
5118 }
5119 
5120 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5121 			   enum addr_type_t type)
5122 {
5123 	const struct nlmsghdr *nlh = cb->nlh;
5124 	struct inet6_fill_args fillargs = {
5125 		.portid = NETLINK_CB(cb->skb).portid,
5126 		.seq = cb->nlh->nlmsg_seq,
5127 		.flags = NLM_F_MULTI,
5128 		.netnsid = -1,
5129 		.type = type,
5130 	};
5131 	struct net *net = sock_net(skb->sk);
5132 	struct net *tgt_net = net;
5133 	int idx, s_idx, s_ip_idx;
5134 	int h, s_h;
5135 	struct net_device *dev;
5136 	struct inet6_dev *idev;
5137 	struct hlist_head *head;
5138 	int err = 0;
5139 
5140 	s_h = cb->args[0];
5141 	s_idx = idx = cb->args[1];
5142 	s_ip_idx = cb->args[2];
5143 
5144 	if (cb->strict_check) {
5145 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5146 						  skb->sk, cb);
5147 		if (err < 0)
5148 			goto put_tgt_net;
5149 
5150 		err = 0;
5151 		if (fillargs.ifindex) {
5152 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5153 			if (!dev) {
5154 				err = -ENODEV;
5155 				goto put_tgt_net;
5156 			}
5157 			idev = __in6_dev_get(dev);
5158 			if (idev) {
5159 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5160 						     &fillargs);
5161 				if (err > 0)
5162 					err = 0;
5163 			}
5164 			goto put_tgt_net;
5165 		}
5166 	}
5167 
5168 	rcu_read_lock();
5169 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5170 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5171 		idx = 0;
5172 		head = &tgt_net->dev_index_head[h];
5173 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5174 			if (idx < s_idx)
5175 				goto cont;
5176 			if (h > s_h || idx > s_idx)
5177 				s_ip_idx = 0;
5178 			idev = __in6_dev_get(dev);
5179 			if (!idev)
5180 				goto cont;
5181 
5182 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5183 					   &fillargs) < 0)
5184 				goto done;
5185 cont:
5186 			idx++;
5187 		}
5188 	}
5189 done:
5190 	rcu_read_unlock();
5191 	cb->args[0] = h;
5192 	cb->args[1] = idx;
5193 put_tgt_net:
5194 	if (fillargs.netnsid >= 0)
5195 		put_net(tgt_net);
5196 
5197 	return skb->len ? : err;
5198 }
5199 
5200 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5201 {
5202 	enum addr_type_t type = UNICAST_ADDR;
5203 
5204 	return inet6_dump_addr(skb, cb, type);
5205 }
5206 
5207 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5208 {
5209 	enum addr_type_t type = MULTICAST_ADDR;
5210 
5211 	return inet6_dump_addr(skb, cb, type);
5212 }
5213 
5214 
5215 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5216 {
5217 	enum addr_type_t type = ANYCAST_ADDR;
5218 
5219 	return inet6_dump_addr(skb, cb, type);
5220 }
5221 
5222 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5223 				       const struct nlmsghdr *nlh,
5224 				       struct nlattr **tb,
5225 				       struct netlink_ext_ack *extack)
5226 {
5227 	struct ifaddrmsg *ifm;
5228 	int i, err;
5229 
5230 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5231 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5232 		return -EINVAL;
5233 	}
5234 
5235 	ifm = nlmsg_data(nlh);
5236 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5237 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5238 		return -EINVAL;
5239 	}
5240 
5241 	if (!netlink_strict_get_check(skb))
5242 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5243 					      ifa_ipv6_policy, extack);
5244 
5245 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5246 					    ifa_ipv6_policy, extack);
5247 	if (err)
5248 		return err;
5249 
5250 	for (i = 0; i <= IFA_MAX; i++) {
5251 		if (!tb[i])
5252 			continue;
5253 
5254 		switch (i) {
5255 		case IFA_TARGET_NETNSID:
5256 		case IFA_ADDRESS:
5257 		case IFA_LOCAL:
5258 			break;
5259 		default:
5260 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5261 			return -EINVAL;
5262 		}
5263 	}
5264 
5265 	return 0;
5266 }
5267 
5268 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5269 			     struct netlink_ext_ack *extack)
5270 {
5271 	struct net *net = sock_net(in_skb->sk);
5272 	struct inet6_fill_args fillargs = {
5273 		.portid = NETLINK_CB(in_skb).portid,
5274 		.seq = nlh->nlmsg_seq,
5275 		.event = RTM_NEWADDR,
5276 		.flags = 0,
5277 		.netnsid = -1,
5278 	};
5279 	struct net *tgt_net = net;
5280 	struct ifaddrmsg *ifm;
5281 	struct nlattr *tb[IFA_MAX+1];
5282 	struct in6_addr *addr = NULL, *peer;
5283 	struct net_device *dev = NULL;
5284 	struct inet6_ifaddr *ifa;
5285 	struct sk_buff *skb;
5286 	int err;
5287 
5288 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5289 	if (err < 0)
5290 		return err;
5291 
5292 	if (tb[IFA_TARGET_NETNSID]) {
5293 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5294 
5295 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5296 						  fillargs.netnsid);
5297 		if (IS_ERR(tgt_net))
5298 			return PTR_ERR(tgt_net);
5299 	}
5300 
5301 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5302 	if (!addr)
5303 		return -EINVAL;
5304 
5305 	ifm = nlmsg_data(nlh);
5306 	if (ifm->ifa_index)
5307 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5308 
5309 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5310 	if (!ifa) {
5311 		err = -EADDRNOTAVAIL;
5312 		goto errout;
5313 	}
5314 
5315 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5316 	if (!skb) {
5317 		err = -ENOBUFS;
5318 		goto errout_ifa;
5319 	}
5320 
5321 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5322 	if (err < 0) {
5323 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5324 		WARN_ON(err == -EMSGSIZE);
5325 		kfree_skb(skb);
5326 		goto errout_ifa;
5327 	}
5328 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5329 errout_ifa:
5330 	in6_ifa_put(ifa);
5331 errout:
5332 	if (dev)
5333 		dev_put(dev);
5334 	if (fillargs.netnsid >= 0)
5335 		put_net(tgt_net);
5336 
5337 	return err;
5338 }
5339 
5340 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5341 {
5342 	struct sk_buff *skb;
5343 	struct net *net = dev_net(ifa->idev->dev);
5344 	struct inet6_fill_args fillargs = {
5345 		.portid = 0,
5346 		.seq = 0,
5347 		.event = event,
5348 		.flags = 0,
5349 		.netnsid = -1,
5350 	};
5351 	int err = -ENOBUFS;
5352 
5353 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5354 	if (!skb)
5355 		goto errout;
5356 
5357 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5358 	if (err < 0) {
5359 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5360 		WARN_ON(err == -EMSGSIZE);
5361 		kfree_skb(skb);
5362 		goto errout;
5363 	}
5364 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5365 	return;
5366 errout:
5367 	if (err < 0)
5368 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5369 }
5370 
5371 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5372 				__s32 *array, int bytes)
5373 {
5374 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5375 
5376 	memset(array, 0, bytes);
5377 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5378 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5379 	array[DEVCONF_MTU6] = cnf->mtu6;
5380 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5381 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5382 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5383 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5384 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5385 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5386 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5387 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5388 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5389 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5390 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5391 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5392 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5393 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5394 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5395 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5396 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5397 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5398 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5399 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5400 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5401 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5402 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5403 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5404 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5405 #ifdef CONFIG_IPV6_ROUTER_PREF
5406 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5407 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5408 		jiffies_to_msecs(cnf->rtr_probe_interval);
5409 #ifdef CONFIG_IPV6_ROUTE_INFO
5410 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5411 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5412 #endif
5413 #endif
5414 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5415 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5416 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5417 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5418 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5419 #endif
5420 #ifdef CONFIG_IPV6_MROUTE
5421 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5422 #endif
5423 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5424 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5425 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5426 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5427 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5428 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5429 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5430 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5431 	/* we omit DEVCONF_STABLE_SECRET for now */
5432 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5433 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5434 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5435 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5436 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5437 #ifdef CONFIG_IPV6_SEG6_HMAC
5438 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5439 #endif
5440 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5441 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5442 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5443 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5444 }
5445 
5446 static inline size_t inet6_ifla6_size(void)
5447 {
5448 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5449 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5450 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5451 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5452 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5453 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5454 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5455 	     + 0;
5456 }
5457 
5458 static inline size_t inet6_if_nlmsg_size(void)
5459 {
5460 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5461 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5462 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5463 	       + nla_total_size(4) /* IFLA_MTU */
5464 	       + nla_total_size(4) /* IFLA_LINK */
5465 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5466 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5467 }
5468 
5469 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5470 					int bytes)
5471 {
5472 	int i;
5473 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5474 	BUG_ON(pad < 0);
5475 
5476 	/* Use put_unaligned() because stats may not be aligned for u64. */
5477 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5478 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5479 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5480 
5481 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5482 }
5483 
5484 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5485 					int bytes, size_t syncpoff)
5486 {
5487 	int i, c;
5488 	u64 buff[IPSTATS_MIB_MAX];
5489 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5490 
5491 	BUG_ON(pad < 0);
5492 
5493 	memset(buff, 0, sizeof(buff));
5494 	buff[0] = IPSTATS_MIB_MAX;
5495 
5496 	for_each_possible_cpu(c) {
5497 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5498 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5499 	}
5500 
5501 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5502 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5503 }
5504 
5505 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5506 			     int bytes)
5507 {
5508 	switch (attrtype) {
5509 	case IFLA_INET6_STATS:
5510 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5511 				     offsetof(struct ipstats_mib, syncp));
5512 		break;
5513 	case IFLA_INET6_ICMP6STATS:
5514 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5515 		break;
5516 	}
5517 }
5518 
5519 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5520 				  u32 ext_filter_mask)
5521 {
5522 	struct nlattr *nla;
5523 	struct ifla_cacheinfo ci;
5524 
5525 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5526 		goto nla_put_failure;
5527 	ci.max_reasm_len = IPV6_MAXPLEN;
5528 	ci.tstamp = cstamp_delta(idev->tstamp);
5529 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5530 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5531 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5532 		goto nla_put_failure;
5533 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5534 	if (!nla)
5535 		goto nla_put_failure;
5536 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5537 
5538 	/* XXX - MC not implemented */
5539 
5540 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5541 		return 0;
5542 
5543 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5544 	if (!nla)
5545 		goto nla_put_failure;
5546 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5547 
5548 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5549 	if (!nla)
5550 		goto nla_put_failure;
5551 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5552 
5553 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5554 	if (!nla)
5555 		goto nla_put_failure;
5556 
5557 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5558 		goto nla_put_failure;
5559 
5560 	read_lock_bh(&idev->lock);
5561 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5562 	read_unlock_bh(&idev->lock);
5563 
5564 	return 0;
5565 
5566 nla_put_failure:
5567 	return -EMSGSIZE;
5568 }
5569 
5570 static size_t inet6_get_link_af_size(const struct net_device *dev,
5571 				     u32 ext_filter_mask)
5572 {
5573 	if (!__in6_dev_get(dev))
5574 		return 0;
5575 
5576 	return inet6_ifla6_size();
5577 }
5578 
5579 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5580 			      u32 ext_filter_mask)
5581 {
5582 	struct inet6_dev *idev = __in6_dev_get(dev);
5583 
5584 	if (!idev)
5585 		return -ENODATA;
5586 
5587 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5588 		return -EMSGSIZE;
5589 
5590 	return 0;
5591 }
5592 
5593 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5594 {
5595 	struct inet6_ifaddr *ifp;
5596 	struct net_device *dev = idev->dev;
5597 	bool clear_token, update_rs = false;
5598 	struct in6_addr ll_addr;
5599 
5600 	ASSERT_RTNL();
5601 
5602 	if (!token)
5603 		return -EINVAL;
5604 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5605 		return -EINVAL;
5606 	if (!ipv6_accept_ra(idev))
5607 		return -EINVAL;
5608 	if (idev->cnf.rtr_solicits == 0)
5609 		return -EINVAL;
5610 
5611 	write_lock_bh(&idev->lock);
5612 
5613 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5614 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5615 
5616 	write_unlock_bh(&idev->lock);
5617 
5618 	clear_token = ipv6_addr_any(token);
5619 	if (clear_token)
5620 		goto update_lft;
5621 
5622 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5623 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5624 			     IFA_F_OPTIMISTIC)) {
5625 		/* If we're not ready, then normal ifup will take care
5626 		 * of this. Otherwise, we need to request our rs here.
5627 		 */
5628 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5629 		update_rs = true;
5630 	}
5631 
5632 update_lft:
5633 	write_lock_bh(&idev->lock);
5634 
5635 	if (update_rs) {
5636 		idev->if_flags |= IF_RS_SENT;
5637 		idev->rs_interval = rfc3315_s14_backoff_init(
5638 			idev->cnf.rtr_solicit_interval);
5639 		idev->rs_probes = 1;
5640 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5641 	}
5642 
5643 	/* Well, that's kinda nasty ... */
5644 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5645 		spin_lock(&ifp->lock);
5646 		if (ifp->tokenized) {
5647 			ifp->valid_lft = 0;
5648 			ifp->prefered_lft = 0;
5649 		}
5650 		spin_unlock(&ifp->lock);
5651 	}
5652 
5653 	write_unlock_bh(&idev->lock);
5654 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5655 	addrconf_verify_rtnl();
5656 	return 0;
5657 }
5658 
5659 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5660 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5661 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5662 };
5663 
5664 static int inet6_validate_link_af(const struct net_device *dev,
5665 				  const struct nlattr *nla)
5666 {
5667 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5668 
5669 	if (dev && !__in6_dev_get(dev))
5670 		return -EAFNOSUPPORT;
5671 
5672 	return nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5673 					   inet6_af_policy, NULL);
5674 }
5675 
5676 static int check_addr_gen_mode(int mode)
5677 {
5678 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5679 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5680 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5681 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5682 		return -EINVAL;
5683 	return 1;
5684 }
5685 
5686 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5687 				int mode)
5688 {
5689 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5690 	    !idev->cnf.stable_secret.initialized &&
5691 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5692 		return -EINVAL;
5693 	return 1;
5694 }
5695 
5696 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5697 {
5698 	int err = -EINVAL;
5699 	struct inet6_dev *idev = __in6_dev_get(dev);
5700 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5701 
5702 	if (!idev)
5703 		return -EAFNOSUPPORT;
5704 
5705 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5706 		BUG();
5707 
5708 	if (tb[IFLA_INET6_TOKEN]) {
5709 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5710 		if (err)
5711 			return err;
5712 	}
5713 
5714 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5715 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5716 
5717 		if (check_addr_gen_mode(mode) < 0 ||
5718 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5719 			return -EINVAL;
5720 
5721 		idev->cnf.addr_gen_mode = mode;
5722 		err = 0;
5723 	}
5724 
5725 	return err;
5726 }
5727 
5728 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5729 			     u32 portid, u32 seq, int event, unsigned int flags)
5730 {
5731 	struct net_device *dev = idev->dev;
5732 	struct ifinfomsg *hdr;
5733 	struct nlmsghdr *nlh;
5734 	void *protoinfo;
5735 
5736 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5737 	if (!nlh)
5738 		return -EMSGSIZE;
5739 
5740 	hdr = nlmsg_data(nlh);
5741 	hdr->ifi_family = AF_INET6;
5742 	hdr->__ifi_pad = 0;
5743 	hdr->ifi_type = dev->type;
5744 	hdr->ifi_index = dev->ifindex;
5745 	hdr->ifi_flags = dev_get_flags(dev);
5746 	hdr->ifi_change = 0;
5747 
5748 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5749 	    (dev->addr_len &&
5750 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5751 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5752 	    (dev->ifindex != dev_get_iflink(dev) &&
5753 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5754 	    nla_put_u8(skb, IFLA_OPERSTATE,
5755 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5756 		goto nla_put_failure;
5757 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5758 	if (!protoinfo)
5759 		goto nla_put_failure;
5760 
5761 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5762 		goto nla_put_failure;
5763 
5764 	nla_nest_end(skb, protoinfo);
5765 	nlmsg_end(skb, nlh);
5766 	return 0;
5767 
5768 nla_put_failure:
5769 	nlmsg_cancel(skb, nlh);
5770 	return -EMSGSIZE;
5771 }
5772 
5773 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5774 				   struct netlink_ext_ack *extack)
5775 {
5776 	struct ifinfomsg *ifm;
5777 
5778 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5779 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5780 		return -EINVAL;
5781 	}
5782 
5783 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5784 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5785 		return -EINVAL;
5786 	}
5787 
5788 	ifm = nlmsg_data(nlh);
5789 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5790 	    ifm->ifi_change || ifm->ifi_index) {
5791 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5792 		return -EINVAL;
5793 	}
5794 
5795 	return 0;
5796 }
5797 
5798 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5799 {
5800 	struct net *net = sock_net(skb->sk);
5801 	int h, s_h;
5802 	int idx = 0, s_idx;
5803 	struct net_device *dev;
5804 	struct inet6_dev *idev;
5805 	struct hlist_head *head;
5806 
5807 	/* only requests using strict checking can pass data to
5808 	 * influence the dump
5809 	 */
5810 	if (cb->strict_check) {
5811 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5812 
5813 		if (err < 0)
5814 			return err;
5815 	}
5816 
5817 	s_h = cb->args[0];
5818 	s_idx = cb->args[1];
5819 
5820 	rcu_read_lock();
5821 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5822 		idx = 0;
5823 		head = &net->dev_index_head[h];
5824 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5825 			if (idx < s_idx)
5826 				goto cont;
5827 			idev = __in6_dev_get(dev);
5828 			if (!idev)
5829 				goto cont;
5830 			if (inet6_fill_ifinfo(skb, idev,
5831 					      NETLINK_CB(cb->skb).portid,
5832 					      cb->nlh->nlmsg_seq,
5833 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5834 				goto out;
5835 cont:
5836 			idx++;
5837 		}
5838 	}
5839 out:
5840 	rcu_read_unlock();
5841 	cb->args[1] = idx;
5842 	cb->args[0] = h;
5843 
5844 	return skb->len;
5845 }
5846 
5847 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5848 {
5849 	struct sk_buff *skb;
5850 	struct net *net = dev_net(idev->dev);
5851 	int err = -ENOBUFS;
5852 
5853 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5854 	if (!skb)
5855 		goto errout;
5856 
5857 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5858 	if (err < 0) {
5859 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5860 		WARN_ON(err == -EMSGSIZE);
5861 		kfree_skb(skb);
5862 		goto errout;
5863 	}
5864 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5865 	return;
5866 errout:
5867 	if (err < 0)
5868 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5869 }
5870 
5871 static inline size_t inet6_prefix_nlmsg_size(void)
5872 {
5873 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5874 	       + nla_total_size(sizeof(struct in6_addr))
5875 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5876 }
5877 
5878 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5879 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5880 			     int event, unsigned int flags)
5881 {
5882 	struct prefixmsg *pmsg;
5883 	struct nlmsghdr *nlh;
5884 	struct prefix_cacheinfo	ci;
5885 
5886 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5887 	if (!nlh)
5888 		return -EMSGSIZE;
5889 
5890 	pmsg = nlmsg_data(nlh);
5891 	pmsg->prefix_family = AF_INET6;
5892 	pmsg->prefix_pad1 = 0;
5893 	pmsg->prefix_pad2 = 0;
5894 	pmsg->prefix_ifindex = idev->dev->ifindex;
5895 	pmsg->prefix_len = pinfo->prefix_len;
5896 	pmsg->prefix_type = pinfo->type;
5897 	pmsg->prefix_pad3 = 0;
5898 	pmsg->prefix_flags = 0;
5899 	if (pinfo->onlink)
5900 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5901 	if (pinfo->autoconf)
5902 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5903 
5904 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5905 		goto nla_put_failure;
5906 	ci.preferred_time = ntohl(pinfo->prefered);
5907 	ci.valid_time = ntohl(pinfo->valid);
5908 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5909 		goto nla_put_failure;
5910 	nlmsg_end(skb, nlh);
5911 	return 0;
5912 
5913 nla_put_failure:
5914 	nlmsg_cancel(skb, nlh);
5915 	return -EMSGSIZE;
5916 }
5917 
5918 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5919 			 struct prefix_info *pinfo)
5920 {
5921 	struct sk_buff *skb;
5922 	struct net *net = dev_net(idev->dev);
5923 	int err = -ENOBUFS;
5924 
5925 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5926 	if (!skb)
5927 		goto errout;
5928 
5929 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5930 	if (err < 0) {
5931 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5932 		WARN_ON(err == -EMSGSIZE);
5933 		kfree_skb(skb);
5934 		goto errout;
5935 	}
5936 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5937 	return;
5938 errout:
5939 	if (err < 0)
5940 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5941 }
5942 
5943 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5944 {
5945 	struct net *net = dev_net(ifp->idev->dev);
5946 
5947 	if (event)
5948 		ASSERT_RTNL();
5949 
5950 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5951 
5952 	switch (event) {
5953 	case RTM_NEWADDR:
5954 		/*
5955 		 * If the address was optimistic
5956 		 * we inserted the route at the start of
5957 		 * our DAD process, so we don't need
5958 		 * to do it again
5959 		 */
5960 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5961 			ip6_ins_rt(net, ifp->rt);
5962 		if (ifp->idev->cnf.forwarding)
5963 			addrconf_join_anycast(ifp);
5964 		if (!ipv6_addr_any(&ifp->peer_addr))
5965 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5966 					      ifp->idev->dev, 0, 0,
5967 					      GFP_ATOMIC);
5968 		break;
5969 	case RTM_DELADDR:
5970 		if (ifp->idev->cnf.forwarding)
5971 			addrconf_leave_anycast(ifp);
5972 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5973 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5974 			struct fib6_info *rt;
5975 
5976 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5977 						       ifp->idev->dev, 0, 0,
5978 						       false);
5979 			if (rt)
5980 				ip6_del_rt(net, rt);
5981 		}
5982 		if (ifp->rt) {
5983 			ip6_del_rt(net, ifp->rt);
5984 			ifp->rt = NULL;
5985 		}
5986 		rt_genid_bump_ipv6(net);
5987 		break;
5988 	}
5989 	atomic_inc(&net->ipv6.dev_addr_genid);
5990 }
5991 
5992 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5993 {
5994 	rcu_read_lock_bh();
5995 	if (likely(ifp->idev->dead == 0))
5996 		__ipv6_ifa_notify(event, ifp);
5997 	rcu_read_unlock_bh();
5998 }
5999 
6000 #ifdef CONFIG_SYSCTL
6001 
6002 static
6003 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6004 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6005 {
6006 	int *valp = ctl->data;
6007 	int val = *valp;
6008 	loff_t pos = *ppos;
6009 	struct ctl_table lctl;
6010 	int ret;
6011 
6012 	/*
6013 	 * ctl->data points to idev->cnf.forwarding, we should
6014 	 * not modify it until we get the rtnl lock.
6015 	 */
6016 	lctl = *ctl;
6017 	lctl.data = &val;
6018 
6019 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6020 
6021 	if (write)
6022 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6023 	if (ret)
6024 		*ppos = pos;
6025 	return ret;
6026 }
6027 
6028 static
6029 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6030 			void __user *buffer, size_t *lenp, loff_t *ppos)
6031 {
6032 	struct inet6_dev *idev = ctl->extra1;
6033 	int min_mtu = IPV6_MIN_MTU;
6034 	struct ctl_table lctl;
6035 
6036 	lctl = *ctl;
6037 	lctl.extra1 = &min_mtu;
6038 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6039 
6040 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6041 }
6042 
6043 static void dev_disable_change(struct inet6_dev *idev)
6044 {
6045 	struct netdev_notifier_info info;
6046 
6047 	if (!idev || !idev->dev)
6048 		return;
6049 
6050 	netdev_notifier_info_init(&info, idev->dev);
6051 	if (idev->cnf.disable_ipv6)
6052 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6053 	else
6054 		addrconf_notify(NULL, NETDEV_UP, &info);
6055 }
6056 
6057 static void addrconf_disable_change(struct net *net, __s32 newf)
6058 {
6059 	struct net_device *dev;
6060 	struct inet6_dev *idev;
6061 
6062 	for_each_netdev(net, dev) {
6063 		idev = __in6_dev_get(dev);
6064 		if (idev) {
6065 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6066 			idev->cnf.disable_ipv6 = newf;
6067 			if (changed)
6068 				dev_disable_change(idev);
6069 		}
6070 	}
6071 }
6072 
6073 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6074 {
6075 	struct net *net;
6076 	int old;
6077 
6078 	if (!rtnl_trylock())
6079 		return restart_syscall();
6080 
6081 	net = (struct net *)table->extra2;
6082 	old = *p;
6083 	*p = newf;
6084 
6085 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6086 		rtnl_unlock();
6087 		return 0;
6088 	}
6089 
6090 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6091 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6092 		addrconf_disable_change(net, newf);
6093 	} else if ((!newf) ^ (!old))
6094 		dev_disable_change((struct inet6_dev *)table->extra1);
6095 
6096 	rtnl_unlock();
6097 	return 0;
6098 }
6099 
6100 static
6101 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6102 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6103 {
6104 	int *valp = ctl->data;
6105 	int val = *valp;
6106 	loff_t pos = *ppos;
6107 	struct ctl_table lctl;
6108 	int ret;
6109 
6110 	/*
6111 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6112 	 * not modify it until we get the rtnl lock.
6113 	 */
6114 	lctl = *ctl;
6115 	lctl.data = &val;
6116 
6117 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6118 
6119 	if (write)
6120 		ret = addrconf_disable_ipv6(ctl, valp, val);
6121 	if (ret)
6122 		*ppos = pos;
6123 	return ret;
6124 }
6125 
6126 static
6127 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6128 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6129 {
6130 	int *valp = ctl->data;
6131 	int ret;
6132 	int old, new;
6133 
6134 	old = *valp;
6135 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6136 	new = *valp;
6137 
6138 	if (write && old != new) {
6139 		struct net *net = ctl->extra2;
6140 
6141 		if (!rtnl_trylock())
6142 			return restart_syscall();
6143 
6144 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6145 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6146 						     NETCONFA_PROXY_NEIGH,
6147 						     NETCONFA_IFINDEX_DEFAULT,
6148 						     net->ipv6.devconf_dflt);
6149 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6150 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6151 						     NETCONFA_PROXY_NEIGH,
6152 						     NETCONFA_IFINDEX_ALL,
6153 						     net->ipv6.devconf_all);
6154 		else {
6155 			struct inet6_dev *idev = ctl->extra1;
6156 
6157 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6158 						     NETCONFA_PROXY_NEIGH,
6159 						     idev->dev->ifindex,
6160 						     &idev->cnf);
6161 		}
6162 		rtnl_unlock();
6163 	}
6164 
6165 	return ret;
6166 }
6167 
6168 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6169 					 void __user *buffer, size_t *lenp,
6170 					 loff_t *ppos)
6171 {
6172 	int ret = 0;
6173 	u32 new_val;
6174 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6175 	struct net *net = (struct net *)ctl->extra2;
6176 	struct ctl_table tmp = {
6177 		.data = &new_val,
6178 		.maxlen = sizeof(new_val),
6179 		.mode = ctl->mode,
6180 	};
6181 
6182 	if (!rtnl_trylock())
6183 		return restart_syscall();
6184 
6185 	new_val = *((u32 *)ctl->data);
6186 
6187 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6188 	if (ret != 0)
6189 		goto out;
6190 
6191 	if (write) {
6192 		if (check_addr_gen_mode(new_val) < 0) {
6193 			ret = -EINVAL;
6194 			goto out;
6195 		}
6196 
6197 		if (idev) {
6198 			if (check_stable_privacy(idev, net, new_val) < 0) {
6199 				ret = -EINVAL;
6200 				goto out;
6201 			}
6202 
6203 			if (idev->cnf.addr_gen_mode != new_val) {
6204 				idev->cnf.addr_gen_mode = new_val;
6205 				addrconf_dev_config(idev->dev);
6206 			}
6207 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6208 			struct net_device *dev;
6209 
6210 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6211 			for_each_netdev(net, dev) {
6212 				idev = __in6_dev_get(dev);
6213 				if (idev &&
6214 				    idev->cnf.addr_gen_mode != new_val) {
6215 					idev->cnf.addr_gen_mode = new_val;
6216 					addrconf_dev_config(idev->dev);
6217 				}
6218 			}
6219 		}
6220 
6221 		*((u32 *)ctl->data) = new_val;
6222 	}
6223 
6224 out:
6225 	rtnl_unlock();
6226 
6227 	return ret;
6228 }
6229 
6230 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6231 					 void __user *buffer, size_t *lenp,
6232 					 loff_t *ppos)
6233 {
6234 	int err;
6235 	struct in6_addr addr;
6236 	char str[IPV6_MAX_STRLEN];
6237 	struct ctl_table lctl = *ctl;
6238 	struct net *net = ctl->extra2;
6239 	struct ipv6_stable_secret *secret = ctl->data;
6240 
6241 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6242 		return -EIO;
6243 
6244 	lctl.maxlen = IPV6_MAX_STRLEN;
6245 	lctl.data = str;
6246 
6247 	if (!rtnl_trylock())
6248 		return restart_syscall();
6249 
6250 	if (!write && !secret->initialized) {
6251 		err = -EIO;
6252 		goto out;
6253 	}
6254 
6255 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6256 	if (err >= sizeof(str)) {
6257 		err = -EIO;
6258 		goto out;
6259 	}
6260 
6261 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6262 	if (err || !write)
6263 		goto out;
6264 
6265 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6266 		err = -EIO;
6267 		goto out;
6268 	}
6269 
6270 	secret->initialized = true;
6271 	secret->secret = addr;
6272 
6273 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6274 		struct net_device *dev;
6275 
6276 		for_each_netdev(net, dev) {
6277 			struct inet6_dev *idev = __in6_dev_get(dev);
6278 
6279 			if (idev) {
6280 				idev->cnf.addr_gen_mode =
6281 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6282 			}
6283 		}
6284 	} else {
6285 		struct inet6_dev *idev = ctl->extra1;
6286 
6287 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6288 	}
6289 
6290 out:
6291 	rtnl_unlock();
6292 
6293 	return err;
6294 }
6295 
6296 static
6297 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6298 						int write,
6299 						void __user *buffer,
6300 						size_t *lenp,
6301 						loff_t *ppos)
6302 {
6303 	int *valp = ctl->data;
6304 	int val = *valp;
6305 	loff_t pos = *ppos;
6306 	struct ctl_table lctl;
6307 	int ret;
6308 
6309 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6310 	 * we should not modify it until we get the rtnl lock.
6311 	 */
6312 	lctl = *ctl;
6313 	lctl.data = &val;
6314 
6315 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6316 
6317 	if (write)
6318 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6319 	if (ret)
6320 		*ppos = pos;
6321 	return ret;
6322 }
6323 
6324 static
6325 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6326 {
6327 	if (rt) {
6328 		if (action)
6329 			rt->dst.flags |= DST_NOPOLICY;
6330 		else
6331 			rt->dst.flags &= ~DST_NOPOLICY;
6332 	}
6333 }
6334 
6335 static
6336 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6337 {
6338 	struct inet6_ifaddr *ifa;
6339 
6340 	read_lock_bh(&idev->lock);
6341 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6342 		spin_lock(&ifa->lock);
6343 		if (ifa->rt) {
6344 			struct fib6_info *rt = ifa->rt;
6345 			int cpu;
6346 
6347 			rcu_read_lock();
6348 			ifa->rt->dst_nopolicy = val ? true : false;
6349 			if (rt->rt6i_pcpu) {
6350 				for_each_possible_cpu(cpu) {
6351 					struct rt6_info **rtp;
6352 
6353 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6354 					addrconf_set_nopolicy(*rtp, val);
6355 				}
6356 			}
6357 			rcu_read_unlock();
6358 		}
6359 		spin_unlock(&ifa->lock);
6360 	}
6361 	read_unlock_bh(&idev->lock);
6362 }
6363 
6364 static
6365 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6366 {
6367 	struct inet6_dev *idev;
6368 	struct net *net;
6369 
6370 	if (!rtnl_trylock())
6371 		return restart_syscall();
6372 
6373 	*valp = val;
6374 
6375 	net = (struct net *)ctl->extra2;
6376 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6377 		rtnl_unlock();
6378 		return 0;
6379 	}
6380 
6381 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6382 		struct net_device *dev;
6383 
6384 		for_each_netdev(net, dev) {
6385 			idev = __in6_dev_get(dev);
6386 			if (idev)
6387 				addrconf_disable_policy_idev(idev, val);
6388 		}
6389 	} else {
6390 		idev = (struct inet6_dev *)ctl->extra1;
6391 		addrconf_disable_policy_idev(idev, val);
6392 	}
6393 
6394 	rtnl_unlock();
6395 	return 0;
6396 }
6397 
6398 static
6399 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6400 				   void __user *buffer, size_t *lenp,
6401 				   loff_t *ppos)
6402 {
6403 	int *valp = ctl->data;
6404 	int val = *valp;
6405 	loff_t pos = *ppos;
6406 	struct ctl_table lctl;
6407 	int ret;
6408 
6409 	lctl = *ctl;
6410 	lctl.data = &val;
6411 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6412 
6413 	if (write && (*valp != val))
6414 		ret = addrconf_disable_policy(ctl, valp, val);
6415 
6416 	if (ret)
6417 		*ppos = pos;
6418 
6419 	return ret;
6420 }
6421 
6422 static int minus_one = -1;
6423 static const int zero = 0;
6424 static const int one = 1;
6425 static const int two_five_five = 255;
6426 
6427 static const struct ctl_table addrconf_sysctl[] = {
6428 	{
6429 		.procname	= "forwarding",
6430 		.data		= &ipv6_devconf.forwarding,
6431 		.maxlen		= sizeof(int),
6432 		.mode		= 0644,
6433 		.proc_handler	= addrconf_sysctl_forward,
6434 	},
6435 	{
6436 		.procname	= "hop_limit",
6437 		.data		= &ipv6_devconf.hop_limit,
6438 		.maxlen		= sizeof(int),
6439 		.mode		= 0644,
6440 		.proc_handler	= proc_dointvec_minmax,
6441 		.extra1		= (void *)&one,
6442 		.extra2		= (void *)&two_five_five,
6443 	},
6444 	{
6445 		.procname	= "mtu",
6446 		.data		= &ipv6_devconf.mtu6,
6447 		.maxlen		= sizeof(int),
6448 		.mode		= 0644,
6449 		.proc_handler	= addrconf_sysctl_mtu,
6450 	},
6451 	{
6452 		.procname	= "accept_ra",
6453 		.data		= &ipv6_devconf.accept_ra,
6454 		.maxlen		= sizeof(int),
6455 		.mode		= 0644,
6456 		.proc_handler	= proc_dointvec,
6457 	},
6458 	{
6459 		.procname	= "accept_redirects",
6460 		.data		= &ipv6_devconf.accept_redirects,
6461 		.maxlen		= sizeof(int),
6462 		.mode		= 0644,
6463 		.proc_handler	= proc_dointvec,
6464 	},
6465 	{
6466 		.procname	= "autoconf",
6467 		.data		= &ipv6_devconf.autoconf,
6468 		.maxlen		= sizeof(int),
6469 		.mode		= 0644,
6470 		.proc_handler	= proc_dointvec,
6471 	},
6472 	{
6473 		.procname	= "dad_transmits",
6474 		.data		= &ipv6_devconf.dad_transmits,
6475 		.maxlen		= sizeof(int),
6476 		.mode		= 0644,
6477 		.proc_handler	= proc_dointvec,
6478 	},
6479 	{
6480 		.procname	= "router_solicitations",
6481 		.data		= &ipv6_devconf.rtr_solicits,
6482 		.maxlen		= sizeof(int),
6483 		.mode		= 0644,
6484 		.proc_handler	= proc_dointvec_minmax,
6485 		.extra1		= &minus_one,
6486 	},
6487 	{
6488 		.procname	= "router_solicitation_interval",
6489 		.data		= &ipv6_devconf.rtr_solicit_interval,
6490 		.maxlen		= sizeof(int),
6491 		.mode		= 0644,
6492 		.proc_handler	= proc_dointvec_jiffies,
6493 	},
6494 	{
6495 		.procname	= "router_solicitation_max_interval",
6496 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6497 		.maxlen		= sizeof(int),
6498 		.mode		= 0644,
6499 		.proc_handler	= proc_dointvec_jiffies,
6500 	},
6501 	{
6502 		.procname	= "router_solicitation_delay",
6503 		.data		= &ipv6_devconf.rtr_solicit_delay,
6504 		.maxlen		= sizeof(int),
6505 		.mode		= 0644,
6506 		.proc_handler	= proc_dointvec_jiffies,
6507 	},
6508 	{
6509 		.procname	= "force_mld_version",
6510 		.data		= &ipv6_devconf.force_mld_version,
6511 		.maxlen		= sizeof(int),
6512 		.mode		= 0644,
6513 		.proc_handler	= proc_dointvec,
6514 	},
6515 	{
6516 		.procname	= "mldv1_unsolicited_report_interval",
6517 		.data		=
6518 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6519 		.maxlen		= sizeof(int),
6520 		.mode		= 0644,
6521 		.proc_handler	= proc_dointvec_ms_jiffies,
6522 	},
6523 	{
6524 		.procname	= "mldv2_unsolicited_report_interval",
6525 		.data		=
6526 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6527 		.maxlen		= sizeof(int),
6528 		.mode		= 0644,
6529 		.proc_handler	= proc_dointvec_ms_jiffies,
6530 	},
6531 	{
6532 		.procname	= "use_tempaddr",
6533 		.data		= &ipv6_devconf.use_tempaddr,
6534 		.maxlen		= sizeof(int),
6535 		.mode		= 0644,
6536 		.proc_handler	= proc_dointvec,
6537 	},
6538 	{
6539 		.procname	= "temp_valid_lft",
6540 		.data		= &ipv6_devconf.temp_valid_lft,
6541 		.maxlen		= sizeof(int),
6542 		.mode		= 0644,
6543 		.proc_handler	= proc_dointvec,
6544 	},
6545 	{
6546 		.procname	= "temp_prefered_lft",
6547 		.data		= &ipv6_devconf.temp_prefered_lft,
6548 		.maxlen		= sizeof(int),
6549 		.mode		= 0644,
6550 		.proc_handler	= proc_dointvec,
6551 	},
6552 	{
6553 		.procname	= "regen_max_retry",
6554 		.data		= &ipv6_devconf.regen_max_retry,
6555 		.maxlen		= sizeof(int),
6556 		.mode		= 0644,
6557 		.proc_handler	= proc_dointvec,
6558 	},
6559 	{
6560 		.procname	= "max_desync_factor",
6561 		.data		= &ipv6_devconf.max_desync_factor,
6562 		.maxlen		= sizeof(int),
6563 		.mode		= 0644,
6564 		.proc_handler	= proc_dointvec,
6565 	},
6566 	{
6567 		.procname	= "max_addresses",
6568 		.data		= &ipv6_devconf.max_addresses,
6569 		.maxlen		= sizeof(int),
6570 		.mode		= 0644,
6571 		.proc_handler	= proc_dointvec,
6572 	},
6573 	{
6574 		.procname	= "accept_ra_defrtr",
6575 		.data		= &ipv6_devconf.accept_ra_defrtr,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec,
6579 	},
6580 	{
6581 		.procname	= "accept_ra_min_hop_limit",
6582 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6583 		.maxlen		= sizeof(int),
6584 		.mode		= 0644,
6585 		.proc_handler	= proc_dointvec,
6586 	},
6587 	{
6588 		.procname	= "accept_ra_pinfo",
6589 		.data		= &ipv6_devconf.accept_ra_pinfo,
6590 		.maxlen		= sizeof(int),
6591 		.mode		= 0644,
6592 		.proc_handler	= proc_dointvec,
6593 	},
6594 #ifdef CONFIG_IPV6_ROUTER_PREF
6595 	{
6596 		.procname	= "accept_ra_rtr_pref",
6597 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6598 		.maxlen		= sizeof(int),
6599 		.mode		= 0644,
6600 		.proc_handler	= proc_dointvec,
6601 	},
6602 	{
6603 		.procname	= "router_probe_interval",
6604 		.data		= &ipv6_devconf.rtr_probe_interval,
6605 		.maxlen		= sizeof(int),
6606 		.mode		= 0644,
6607 		.proc_handler	= proc_dointvec_jiffies,
6608 	},
6609 #ifdef CONFIG_IPV6_ROUTE_INFO
6610 	{
6611 		.procname	= "accept_ra_rt_info_min_plen",
6612 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6613 		.maxlen		= sizeof(int),
6614 		.mode		= 0644,
6615 		.proc_handler	= proc_dointvec,
6616 	},
6617 	{
6618 		.procname	= "accept_ra_rt_info_max_plen",
6619 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6620 		.maxlen		= sizeof(int),
6621 		.mode		= 0644,
6622 		.proc_handler	= proc_dointvec,
6623 	},
6624 #endif
6625 #endif
6626 	{
6627 		.procname	= "proxy_ndp",
6628 		.data		= &ipv6_devconf.proxy_ndp,
6629 		.maxlen		= sizeof(int),
6630 		.mode		= 0644,
6631 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6632 	},
6633 	{
6634 		.procname	= "accept_source_route",
6635 		.data		= &ipv6_devconf.accept_source_route,
6636 		.maxlen		= sizeof(int),
6637 		.mode		= 0644,
6638 		.proc_handler	= proc_dointvec,
6639 	},
6640 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6641 	{
6642 		.procname	= "optimistic_dad",
6643 		.data		= &ipv6_devconf.optimistic_dad,
6644 		.maxlen		= sizeof(int),
6645 		.mode		= 0644,
6646 		.proc_handler   = proc_dointvec,
6647 	},
6648 	{
6649 		.procname	= "use_optimistic",
6650 		.data		= &ipv6_devconf.use_optimistic,
6651 		.maxlen		= sizeof(int),
6652 		.mode		= 0644,
6653 		.proc_handler	= proc_dointvec,
6654 	},
6655 #endif
6656 #ifdef CONFIG_IPV6_MROUTE
6657 	{
6658 		.procname	= "mc_forwarding",
6659 		.data		= &ipv6_devconf.mc_forwarding,
6660 		.maxlen		= sizeof(int),
6661 		.mode		= 0444,
6662 		.proc_handler	= proc_dointvec,
6663 	},
6664 #endif
6665 	{
6666 		.procname	= "disable_ipv6",
6667 		.data		= &ipv6_devconf.disable_ipv6,
6668 		.maxlen		= sizeof(int),
6669 		.mode		= 0644,
6670 		.proc_handler	= addrconf_sysctl_disable,
6671 	},
6672 	{
6673 		.procname	= "accept_dad",
6674 		.data		= &ipv6_devconf.accept_dad,
6675 		.maxlen		= sizeof(int),
6676 		.mode		= 0644,
6677 		.proc_handler	= proc_dointvec,
6678 	},
6679 	{
6680 		.procname	= "force_tllao",
6681 		.data		= &ipv6_devconf.force_tllao,
6682 		.maxlen		= sizeof(int),
6683 		.mode		= 0644,
6684 		.proc_handler	= proc_dointvec
6685 	},
6686 	{
6687 		.procname	= "ndisc_notify",
6688 		.data		= &ipv6_devconf.ndisc_notify,
6689 		.maxlen		= sizeof(int),
6690 		.mode		= 0644,
6691 		.proc_handler	= proc_dointvec
6692 	},
6693 	{
6694 		.procname	= "suppress_frag_ndisc",
6695 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6696 		.maxlen		= sizeof(int),
6697 		.mode		= 0644,
6698 		.proc_handler	= proc_dointvec
6699 	},
6700 	{
6701 		.procname	= "accept_ra_from_local",
6702 		.data		= &ipv6_devconf.accept_ra_from_local,
6703 		.maxlen		= sizeof(int),
6704 		.mode		= 0644,
6705 		.proc_handler	= proc_dointvec,
6706 	},
6707 	{
6708 		.procname	= "accept_ra_mtu",
6709 		.data		= &ipv6_devconf.accept_ra_mtu,
6710 		.maxlen		= sizeof(int),
6711 		.mode		= 0644,
6712 		.proc_handler	= proc_dointvec,
6713 	},
6714 	{
6715 		.procname	= "stable_secret",
6716 		.data		= &ipv6_devconf.stable_secret,
6717 		.maxlen		= IPV6_MAX_STRLEN,
6718 		.mode		= 0600,
6719 		.proc_handler	= addrconf_sysctl_stable_secret,
6720 	},
6721 	{
6722 		.procname	= "use_oif_addrs_only",
6723 		.data		= &ipv6_devconf.use_oif_addrs_only,
6724 		.maxlen		= sizeof(int),
6725 		.mode		= 0644,
6726 		.proc_handler	= proc_dointvec,
6727 	},
6728 	{
6729 		.procname	= "ignore_routes_with_linkdown",
6730 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6731 		.maxlen		= sizeof(int),
6732 		.mode		= 0644,
6733 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6734 	},
6735 	{
6736 		.procname	= "drop_unicast_in_l2_multicast",
6737 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6738 		.maxlen		= sizeof(int),
6739 		.mode		= 0644,
6740 		.proc_handler	= proc_dointvec,
6741 	},
6742 	{
6743 		.procname	= "drop_unsolicited_na",
6744 		.data		= &ipv6_devconf.drop_unsolicited_na,
6745 		.maxlen		= sizeof(int),
6746 		.mode		= 0644,
6747 		.proc_handler	= proc_dointvec,
6748 	},
6749 	{
6750 		.procname	= "keep_addr_on_down",
6751 		.data		= &ipv6_devconf.keep_addr_on_down,
6752 		.maxlen		= sizeof(int),
6753 		.mode		= 0644,
6754 		.proc_handler	= proc_dointvec,
6755 
6756 	},
6757 	{
6758 		.procname	= "seg6_enabled",
6759 		.data		= &ipv6_devconf.seg6_enabled,
6760 		.maxlen		= sizeof(int),
6761 		.mode		= 0644,
6762 		.proc_handler	= proc_dointvec,
6763 	},
6764 #ifdef CONFIG_IPV6_SEG6_HMAC
6765 	{
6766 		.procname	= "seg6_require_hmac",
6767 		.data		= &ipv6_devconf.seg6_require_hmac,
6768 		.maxlen		= sizeof(int),
6769 		.mode		= 0644,
6770 		.proc_handler	= proc_dointvec,
6771 	},
6772 #endif
6773 	{
6774 		.procname       = "enhanced_dad",
6775 		.data           = &ipv6_devconf.enhanced_dad,
6776 		.maxlen         = sizeof(int),
6777 		.mode           = 0644,
6778 		.proc_handler   = proc_dointvec,
6779 	},
6780 	{
6781 		.procname		= "addr_gen_mode",
6782 		.data			= &ipv6_devconf.addr_gen_mode,
6783 		.maxlen			= sizeof(int),
6784 		.mode			= 0644,
6785 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6786 	},
6787 	{
6788 		.procname       = "disable_policy",
6789 		.data           = &ipv6_devconf.disable_policy,
6790 		.maxlen         = sizeof(int),
6791 		.mode           = 0644,
6792 		.proc_handler   = addrconf_sysctl_disable_policy,
6793 	},
6794 	{
6795 		.procname	= "ndisc_tclass",
6796 		.data		= &ipv6_devconf.ndisc_tclass,
6797 		.maxlen		= sizeof(int),
6798 		.mode		= 0644,
6799 		.proc_handler	= proc_dointvec_minmax,
6800 		.extra1		= (void *)&zero,
6801 		.extra2		= (void *)&two_five_five,
6802 	},
6803 	{
6804 		/* sentinel */
6805 	}
6806 };
6807 
6808 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6809 		struct inet6_dev *idev, struct ipv6_devconf *p)
6810 {
6811 	int i, ifindex;
6812 	struct ctl_table *table;
6813 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6814 
6815 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6816 	if (!table)
6817 		goto out;
6818 
6819 	for (i = 0; table[i].data; i++) {
6820 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6821 		/* If one of these is already set, then it is not safe to
6822 		 * overwrite either of them: this makes proc_dointvec_minmax
6823 		 * usable.
6824 		 */
6825 		if (!table[i].extra1 && !table[i].extra2) {
6826 			table[i].extra1 = idev; /* embedded; no ref */
6827 			table[i].extra2 = net;
6828 		}
6829 	}
6830 
6831 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6832 
6833 	p->sysctl_header = register_net_sysctl(net, path, table);
6834 	if (!p->sysctl_header)
6835 		goto free;
6836 
6837 	if (!strcmp(dev_name, "all"))
6838 		ifindex = NETCONFA_IFINDEX_ALL;
6839 	else if (!strcmp(dev_name, "default"))
6840 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6841 	else
6842 		ifindex = idev->dev->ifindex;
6843 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6844 				     ifindex, p);
6845 	return 0;
6846 
6847 free:
6848 	kfree(table);
6849 out:
6850 	return -ENOBUFS;
6851 }
6852 
6853 static void __addrconf_sysctl_unregister(struct net *net,
6854 					 struct ipv6_devconf *p, int ifindex)
6855 {
6856 	struct ctl_table *table;
6857 
6858 	if (!p->sysctl_header)
6859 		return;
6860 
6861 	table = p->sysctl_header->ctl_table_arg;
6862 	unregister_net_sysctl_table(p->sysctl_header);
6863 	p->sysctl_header = NULL;
6864 	kfree(table);
6865 
6866 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6867 }
6868 
6869 static int addrconf_sysctl_register(struct inet6_dev *idev)
6870 {
6871 	int err;
6872 
6873 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6874 		return -EINVAL;
6875 
6876 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6877 				    &ndisc_ifinfo_sysctl_change);
6878 	if (err)
6879 		return err;
6880 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6881 					 idev, &idev->cnf);
6882 	if (err)
6883 		neigh_sysctl_unregister(idev->nd_parms);
6884 
6885 	return err;
6886 }
6887 
6888 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6889 {
6890 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6891 				     idev->dev->ifindex);
6892 	neigh_sysctl_unregister(idev->nd_parms);
6893 }
6894 
6895 
6896 #endif
6897 
6898 static int __net_init addrconf_init_net(struct net *net)
6899 {
6900 	int err = -ENOMEM;
6901 	struct ipv6_devconf *all, *dflt;
6902 
6903 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6904 	if (!all)
6905 		goto err_alloc_all;
6906 
6907 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6908 	if (!dflt)
6909 		goto err_alloc_dflt;
6910 
6911 	if (IS_ENABLED(CONFIG_SYSCTL) &&
6912 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
6913 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
6914 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
6915 	}
6916 
6917 	/* these will be inherited by all namespaces */
6918 	dflt->autoconf = ipv6_defaults.autoconf;
6919 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6920 
6921 	dflt->stable_secret.initialized = false;
6922 	all->stable_secret.initialized = false;
6923 
6924 	net->ipv6.devconf_all = all;
6925 	net->ipv6.devconf_dflt = dflt;
6926 
6927 #ifdef CONFIG_SYSCTL
6928 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6929 	if (err < 0)
6930 		goto err_reg_all;
6931 
6932 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6933 	if (err < 0)
6934 		goto err_reg_dflt;
6935 #endif
6936 	return 0;
6937 
6938 #ifdef CONFIG_SYSCTL
6939 err_reg_dflt:
6940 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6941 err_reg_all:
6942 	kfree(dflt);
6943 #endif
6944 err_alloc_dflt:
6945 	kfree(all);
6946 err_alloc_all:
6947 	return err;
6948 }
6949 
6950 static void __net_exit addrconf_exit_net(struct net *net)
6951 {
6952 #ifdef CONFIG_SYSCTL
6953 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6954 				     NETCONFA_IFINDEX_DEFAULT);
6955 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6956 				     NETCONFA_IFINDEX_ALL);
6957 #endif
6958 	kfree(net->ipv6.devconf_dflt);
6959 	kfree(net->ipv6.devconf_all);
6960 }
6961 
6962 static struct pernet_operations addrconf_ops = {
6963 	.init = addrconf_init_net,
6964 	.exit = addrconf_exit_net,
6965 };
6966 
6967 static struct rtnl_af_ops inet6_ops __read_mostly = {
6968 	.family		  = AF_INET6,
6969 	.fill_link_af	  = inet6_fill_link_af,
6970 	.get_link_af_size = inet6_get_link_af_size,
6971 	.validate_link_af = inet6_validate_link_af,
6972 	.set_link_af	  = inet6_set_link_af,
6973 };
6974 
6975 /*
6976  *	Init / cleanup code
6977  */
6978 
6979 int __init addrconf_init(void)
6980 {
6981 	struct inet6_dev *idev;
6982 	int i, err;
6983 
6984 	err = ipv6_addr_label_init();
6985 	if (err < 0) {
6986 		pr_crit("%s: cannot initialize default policy table: %d\n",
6987 			__func__, err);
6988 		goto out;
6989 	}
6990 
6991 	err = register_pernet_subsys(&addrconf_ops);
6992 	if (err < 0)
6993 		goto out_addrlabel;
6994 
6995 	addrconf_wq = create_workqueue("ipv6_addrconf");
6996 	if (!addrconf_wq) {
6997 		err = -ENOMEM;
6998 		goto out_nowq;
6999 	}
7000 
7001 	/* The addrconf netdev notifier requires that loopback_dev
7002 	 * has it's ipv6 private information allocated and setup
7003 	 * before it can bring up and give link-local addresses
7004 	 * to other devices which are up.
7005 	 *
7006 	 * Unfortunately, loopback_dev is not necessarily the first
7007 	 * entry in the global dev_base list of net devices.  In fact,
7008 	 * it is likely to be the very last entry on that list.
7009 	 * So this causes the notifier registry below to try and
7010 	 * give link-local addresses to all devices besides loopback_dev
7011 	 * first, then loopback_dev, which cases all the non-loopback_dev
7012 	 * devices to fail to get a link-local address.
7013 	 *
7014 	 * So, as a temporary fix, allocate the ipv6 structure for
7015 	 * loopback_dev first by hand.
7016 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7017 	 * device and it being up should be removed.
7018 	 */
7019 	rtnl_lock();
7020 	idev = ipv6_add_dev(init_net.loopback_dev);
7021 	rtnl_unlock();
7022 	if (IS_ERR(idev)) {
7023 		err = PTR_ERR(idev);
7024 		goto errlo;
7025 	}
7026 
7027 	ip6_route_init_special_entries();
7028 
7029 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7030 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7031 
7032 	register_netdevice_notifier(&ipv6_dev_notf);
7033 
7034 	addrconf_verify();
7035 
7036 	rtnl_af_register(&inet6_ops);
7037 
7038 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7039 				   NULL, inet6_dump_ifinfo, 0);
7040 	if (err < 0)
7041 		goto errout;
7042 
7043 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7044 				   inet6_rtm_newaddr, NULL, 0);
7045 	if (err < 0)
7046 		goto errout;
7047 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7048 				   inet6_rtm_deladdr, NULL, 0);
7049 	if (err < 0)
7050 		goto errout;
7051 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7052 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7053 				   RTNL_FLAG_DOIT_UNLOCKED);
7054 	if (err < 0)
7055 		goto errout;
7056 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7057 				   NULL, inet6_dump_ifmcaddr, 0);
7058 	if (err < 0)
7059 		goto errout;
7060 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7061 				   NULL, inet6_dump_ifacaddr, 0);
7062 	if (err < 0)
7063 		goto errout;
7064 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7065 				   inet6_netconf_get_devconf,
7066 				   inet6_netconf_dump_devconf,
7067 				   RTNL_FLAG_DOIT_UNLOCKED);
7068 	if (err < 0)
7069 		goto errout;
7070 	err = ipv6_addr_label_rtnl_register();
7071 	if (err < 0)
7072 		goto errout;
7073 
7074 	return 0;
7075 errout:
7076 	rtnl_unregister_all(PF_INET6);
7077 	rtnl_af_unregister(&inet6_ops);
7078 	unregister_netdevice_notifier(&ipv6_dev_notf);
7079 errlo:
7080 	destroy_workqueue(addrconf_wq);
7081 out_nowq:
7082 	unregister_pernet_subsys(&addrconf_ops);
7083 out_addrlabel:
7084 	ipv6_addr_label_cleanup();
7085 out:
7086 	return err;
7087 }
7088 
7089 void addrconf_cleanup(void)
7090 {
7091 	struct net_device *dev;
7092 	int i;
7093 
7094 	unregister_netdevice_notifier(&ipv6_dev_notf);
7095 	unregister_pernet_subsys(&addrconf_ops);
7096 	ipv6_addr_label_cleanup();
7097 
7098 	rtnl_af_unregister(&inet6_ops);
7099 
7100 	rtnl_lock();
7101 
7102 	/* clean dev list */
7103 	for_each_netdev(&init_net, dev) {
7104 		if (__in6_dev_get(dev) == NULL)
7105 			continue;
7106 		addrconf_ifdown(dev, 1);
7107 	}
7108 	addrconf_ifdown(init_net.loopback_dev, 2);
7109 
7110 	/*
7111 	 *	Check hash table.
7112 	 */
7113 	spin_lock_bh(&addrconf_hash_lock);
7114 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7115 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7116 	spin_unlock_bh(&addrconf_hash_lock);
7117 	cancel_delayed_work(&addr_chk_work);
7118 	rtnl_unlock();
7119 
7120 	destroy_workqueue(addrconf_wq);
7121 }
7122