xref: /openbmc/linux/net/ipv6/addrconf.c (revision 786e0007e29a58f563bce744e958c692c7cbd435)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181 				   bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188 				struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191 	.forwarding		= 0,
192 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
193 	.mtu6			= IPV6_MIN_MTU,
194 	.accept_ra		= 1,
195 	.accept_redirects	= 1,
196 	.autoconf		= 1,
197 	.force_mld_version	= 0,
198 	.mldv1_unsolicited_report_interval = 10 * HZ,
199 	.mldv2_unsolicited_report_interval = HZ,
200 	.dad_transmits		= 1,
201 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
202 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
203 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
205 	.use_tempaddr		= 0,
206 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
207 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
208 	.regen_max_retry	= REGEN_MAX_RETRY,
209 	.max_desync_factor	= MAX_DESYNC_FACTOR,
210 	.max_addresses		= IPV6_MAX_ADDRESSES,
211 	.accept_ra_defrtr	= 1,
212 	.accept_ra_from_local	= 0,
213 	.accept_ra_min_hop_limit= 1,
214 	.accept_ra_pinfo	= 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216 	.accept_ra_rtr_pref	= 1,
217 	.rtr_probe_interval	= 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219 	.accept_ra_rt_info_min_plen = 0,
220 	.accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223 	.proxy_ndp		= 0,
224 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
225 	.disable_ipv6		= 0,
226 	.accept_dad		= 0,
227 	.suppress_frag_ndisc	= 1,
228 	.accept_ra_mtu		= 1,
229 	.stable_secret		= {
230 		.initialized = false,
231 	},
232 	.use_oif_addrs_only	= 0,
233 	.ignore_routes_with_linkdown = 0,
234 	.keep_addr_on_down	= 0,
235 	.seg6_enabled		= 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237 	.seg6_require_hmac	= 0,
238 #endif
239 	.enhanced_dad           = 1,
240 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
241 	.disable_policy		= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.accept_ra_from_local	= 0,
267 	.accept_ra_min_hop_limit= 1,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 
389 	ndev->cnf.mtu6 = dev->mtu;
390 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
391 	if (!ndev->nd_parms) {
392 		kfree(ndev);
393 		return ERR_PTR(err);
394 	}
395 	if (ndev->cnf.forwarding)
396 		dev_disable_lro(dev);
397 	/* We refer to the device */
398 	dev_hold(dev);
399 
400 	if (snmp6_alloc_dev(ndev) < 0) {
401 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
402 			   __func__);
403 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
404 		dev_put(dev);
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 
409 	if (snmp6_register_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
411 			   __func__, dev->name);
412 		goto err_release;
413 	}
414 
415 	/* One reference from device. */
416 	refcount_set(&ndev->refcnt, 1);
417 
418 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
419 		ndev->cnf.accept_dad = -1;
420 
421 #if IS_ENABLED(CONFIG_IPV6_SIT)
422 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
423 		pr_info("%s: Disabled Multicast RS\n", dev->name);
424 		ndev->cnf.rtr_solicits = 0;
425 	}
426 #endif
427 
428 	INIT_LIST_HEAD(&ndev->tempaddr_list);
429 	ndev->desync_factor = U32_MAX;
430 	if ((dev->flags&IFF_LOOPBACK) ||
431 	    dev->type == ARPHRD_TUNNEL ||
432 	    dev->type == ARPHRD_TUNNEL6 ||
433 	    dev->type == ARPHRD_SIT ||
434 	    dev->type == ARPHRD_NONE) {
435 		ndev->cnf.use_tempaddr = -1;
436 	} else
437 		ipv6_regen_rndid(ndev);
438 
439 	ndev->token = in6addr_any;
440 
441 	if (netif_running(dev) && addrconf_link_ready(dev))
442 		ndev->if_flags |= IF_READY;
443 
444 	ipv6_mc_init_dev(ndev);
445 	ndev->tstamp = jiffies;
446 	err = addrconf_sysctl_register(ndev);
447 	if (err) {
448 		ipv6_mc_destroy_dev(ndev);
449 		snmp6_unregister_dev(ndev);
450 		goto err_release;
451 	}
452 	/* protected by rtnl_lock */
453 	rcu_assign_pointer(dev->ip6_ptr, ndev);
454 
455 	/* Join interface-local all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
457 
458 	/* Join all-node multicast group */
459 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
460 
461 	/* Join all-router multicast group if forwarding is set */
462 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
463 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
464 
465 	return ndev;
466 
467 err_release:
468 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
469 	ndev->dead = 1;
470 	in6_dev_finish_destroy(ndev);
471 	return ERR_PTR(err);
472 }
473 
474 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
475 {
476 	struct inet6_dev *idev;
477 
478 	ASSERT_RTNL();
479 
480 	idev = __in6_dev_get(dev);
481 	if (!idev) {
482 		idev = ipv6_add_dev(dev);
483 		if (IS_ERR(idev))
484 			return NULL;
485 	}
486 
487 	if (dev->flags&IFF_UP)
488 		ipv6_mc_up(idev);
489 	return idev;
490 }
491 
492 static int inet6_netconf_msgsize_devconf(int type)
493 {
494 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
495 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
496 	bool all = false;
497 
498 	if (type == NETCONFA_ALL)
499 		all = true;
500 
501 	if (all || type == NETCONFA_FORWARDING)
502 		size += nla_total_size(4);
503 #ifdef CONFIG_IPV6_MROUTE
504 	if (all || type == NETCONFA_MC_FORWARDING)
505 		size += nla_total_size(4);
506 #endif
507 	if (all || type == NETCONFA_PROXY_NEIGH)
508 		size += nla_total_size(4);
509 
510 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
511 		size += nla_total_size(4);
512 
513 	return size;
514 }
515 
516 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
517 				      struct ipv6_devconf *devconf, u32 portid,
518 				      u32 seq, int event, unsigned int flags,
519 				      int type)
520 {
521 	struct nlmsghdr  *nlh;
522 	struct netconfmsg *ncm;
523 	bool all = false;
524 
525 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
526 			flags);
527 	if (!nlh)
528 		return -EMSGSIZE;
529 
530 	if (type == NETCONFA_ALL)
531 		all = true;
532 
533 	ncm = nlmsg_data(nlh);
534 	ncm->ncm_family = AF_INET6;
535 
536 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
537 		goto nla_put_failure;
538 
539 	if (!devconf)
540 		goto out;
541 
542 	if ((all || type == NETCONFA_FORWARDING) &&
543 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
544 		goto nla_put_failure;
545 #ifdef CONFIG_IPV6_MROUTE
546 	if ((all || type == NETCONFA_MC_FORWARDING) &&
547 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
548 			devconf->mc_forwarding) < 0)
549 		goto nla_put_failure;
550 #endif
551 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
552 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
553 		goto nla_put_failure;
554 
555 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
556 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
557 			devconf->ignore_routes_with_linkdown) < 0)
558 		goto nla_put_failure;
559 
560 out:
561 	nlmsg_end(skb, nlh);
562 	return 0;
563 
564 nla_put_failure:
565 	nlmsg_cancel(skb, nlh);
566 	return -EMSGSIZE;
567 }
568 
569 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
570 				  int ifindex, struct ipv6_devconf *devconf)
571 {
572 	struct sk_buff *skb;
573 	int err = -ENOBUFS;
574 
575 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
576 	if (!skb)
577 		goto errout;
578 
579 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
580 					 event, 0, type);
581 	if (err < 0) {
582 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
583 		WARN_ON(err == -EMSGSIZE);
584 		kfree_skb(skb);
585 		goto errout;
586 	}
587 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
588 	return;
589 errout:
590 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
591 }
592 
593 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
594 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
595 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
596 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
597 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
598 };
599 
600 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
601 				     struct nlmsghdr *nlh,
602 				     struct netlink_ext_ack *extack)
603 {
604 	struct net *net = sock_net(in_skb->sk);
605 	struct nlattr *tb[NETCONFA_MAX+1];
606 	struct inet6_dev *in6_dev = NULL;
607 	struct net_device *dev = NULL;
608 	struct netconfmsg *ncm;
609 	struct sk_buff *skb;
610 	struct ipv6_devconf *devconf;
611 	int ifindex;
612 	int err;
613 
614 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
615 			  devconf_ipv6_policy, extack);
616 	if (err < 0)
617 		return err;
618 
619 	if (!tb[NETCONFA_IFINDEX])
620 		return -EINVAL;
621 
622 	err = -EINVAL;
623 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
624 	switch (ifindex) {
625 	case NETCONFA_IFINDEX_ALL:
626 		devconf = net->ipv6.devconf_all;
627 		break;
628 	case NETCONFA_IFINDEX_DEFAULT:
629 		devconf = net->ipv6.devconf_dflt;
630 		break;
631 	default:
632 		dev = dev_get_by_index(net, ifindex);
633 		if (!dev)
634 			return -EINVAL;
635 		in6_dev = in6_dev_get(dev);
636 		if (!in6_dev)
637 			goto errout;
638 		devconf = &in6_dev->cnf;
639 		break;
640 	}
641 
642 	err = -ENOBUFS;
643 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
644 	if (!skb)
645 		goto errout;
646 
647 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
648 					 NETLINK_CB(in_skb).portid,
649 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
650 					 NETCONFA_ALL);
651 	if (err < 0) {
652 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
653 		WARN_ON(err == -EMSGSIZE);
654 		kfree_skb(skb);
655 		goto errout;
656 	}
657 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
658 errout:
659 	if (in6_dev)
660 		in6_dev_put(in6_dev);
661 	if (dev)
662 		dev_put(dev);
663 	return err;
664 }
665 
666 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
667 				      struct netlink_callback *cb)
668 {
669 	struct net *net = sock_net(skb->sk);
670 	int h, s_h;
671 	int idx, s_idx;
672 	struct net_device *dev;
673 	struct inet6_dev *idev;
674 	struct hlist_head *head;
675 
676 	s_h = cb->args[0];
677 	s_idx = idx = cb->args[1];
678 
679 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
680 		idx = 0;
681 		head = &net->dev_index_head[h];
682 		rcu_read_lock();
683 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
684 			  net->dev_base_seq;
685 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
686 			if (idx < s_idx)
687 				goto cont;
688 			idev = __in6_dev_get(dev);
689 			if (!idev)
690 				goto cont;
691 
692 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
693 						       &idev->cnf,
694 						       NETLINK_CB(cb->skb).portid,
695 						       cb->nlh->nlmsg_seq,
696 						       RTM_NEWNETCONF,
697 						       NLM_F_MULTI,
698 						       NETCONFA_ALL) < 0) {
699 				rcu_read_unlock();
700 				goto done;
701 			}
702 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
703 cont:
704 			idx++;
705 		}
706 		rcu_read_unlock();
707 	}
708 	if (h == NETDEV_HASHENTRIES) {
709 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
710 					       net->ipv6.devconf_all,
711 					       NETLINK_CB(cb->skb).portid,
712 					       cb->nlh->nlmsg_seq,
713 					       RTM_NEWNETCONF, NLM_F_MULTI,
714 					       NETCONFA_ALL) < 0)
715 			goto done;
716 		else
717 			h++;
718 	}
719 	if (h == NETDEV_HASHENTRIES + 1) {
720 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
721 					       net->ipv6.devconf_dflt,
722 					       NETLINK_CB(cb->skb).portid,
723 					       cb->nlh->nlmsg_seq,
724 					       RTM_NEWNETCONF, NLM_F_MULTI,
725 					       NETCONFA_ALL) < 0)
726 			goto done;
727 		else
728 			h++;
729 	}
730 done:
731 	cb->args[0] = h;
732 	cb->args[1] = idx;
733 
734 	return skb->len;
735 }
736 
737 #ifdef CONFIG_SYSCTL
738 static void dev_forward_change(struct inet6_dev *idev)
739 {
740 	struct net_device *dev;
741 	struct inet6_ifaddr *ifa;
742 
743 	if (!idev)
744 		return;
745 	dev = idev->dev;
746 	if (idev->cnf.forwarding)
747 		dev_disable_lro(dev);
748 	if (dev->flags & IFF_MULTICAST) {
749 		if (idev->cnf.forwarding) {
750 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
751 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
752 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
753 		} else {
754 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
755 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
756 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
757 		}
758 	}
759 
760 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
761 		if (ifa->flags&IFA_F_TENTATIVE)
762 			continue;
763 		if (idev->cnf.forwarding)
764 			addrconf_join_anycast(ifa);
765 		else
766 			addrconf_leave_anycast(ifa);
767 	}
768 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
769 				     NETCONFA_FORWARDING,
770 				     dev->ifindex, &idev->cnf);
771 }
772 
773 
774 static void addrconf_forward_change(struct net *net, __s32 newf)
775 {
776 	struct net_device *dev;
777 	struct inet6_dev *idev;
778 
779 	for_each_netdev(net, dev) {
780 		idev = __in6_dev_get(dev);
781 		if (idev) {
782 			int changed = (!idev->cnf.forwarding) ^ (!newf);
783 			idev->cnf.forwarding = newf;
784 			if (changed)
785 				dev_forward_change(idev);
786 		}
787 	}
788 }
789 
790 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
791 {
792 	struct net *net;
793 	int old;
794 
795 	if (!rtnl_trylock())
796 		return restart_syscall();
797 
798 	net = (struct net *)table->extra2;
799 	old = *p;
800 	*p = newf;
801 
802 	if (p == &net->ipv6.devconf_dflt->forwarding) {
803 		if ((!newf) ^ (!old))
804 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
805 						     NETCONFA_FORWARDING,
806 						     NETCONFA_IFINDEX_DEFAULT,
807 						     net->ipv6.devconf_dflt);
808 		rtnl_unlock();
809 		return 0;
810 	}
811 
812 	if (p == &net->ipv6.devconf_all->forwarding) {
813 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
814 
815 		net->ipv6.devconf_dflt->forwarding = newf;
816 		if ((!newf) ^ (!old_dflt))
817 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
818 						     NETCONFA_FORWARDING,
819 						     NETCONFA_IFINDEX_DEFAULT,
820 						     net->ipv6.devconf_dflt);
821 
822 		addrconf_forward_change(net, newf);
823 		if ((!newf) ^ (!old))
824 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
825 						     NETCONFA_FORWARDING,
826 						     NETCONFA_IFINDEX_ALL,
827 						     net->ipv6.devconf_all);
828 	} else if ((!newf) ^ (!old))
829 		dev_forward_change((struct inet6_dev *)table->extra1);
830 	rtnl_unlock();
831 
832 	if (newf)
833 		rt6_purge_dflt_routers(net);
834 	return 1;
835 }
836 
837 static void addrconf_linkdown_change(struct net *net, __s32 newf)
838 {
839 	struct net_device *dev;
840 	struct inet6_dev *idev;
841 
842 	for_each_netdev(net, dev) {
843 		idev = __in6_dev_get(dev);
844 		if (idev) {
845 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
846 
847 			idev->cnf.ignore_routes_with_linkdown = newf;
848 			if (changed)
849 				inet6_netconf_notify_devconf(dev_net(dev),
850 							     RTM_NEWNETCONF,
851 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
852 							     dev->ifindex,
853 							     &idev->cnf);
854 		}
855 	}
856 }
857 
858 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
859 {
860 	struct net *net;
861 	int old;
862 
863 	if (!rtnl_trylock())
864 		return restart_syscall();
865 
866 	net = (struct net *)table->extra2;
867 	old = *p;
868 	*p = newf;
869 
870 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
871 		if ((!newf) ^ (!old))
872 			inet6_netconf_notify_devconf(net,
873 						     RTM_NEWNETCONF,
874 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
875 						     NETCONFA_IFINDEX_DEFAULT,
876 						     net->ipv6.devconf_dflt);
877 		rtnl_unlock();
878 		return 0;
879 	}
880 
881 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
882 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
883 		addrconf_linkdown_change(net, newf);
884 		if ((!newf) ^ (!old))
885 			inet6_netconf_notify_devconf(net,
886 						     RTM_NEWNETCONF,
887 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
888 						     NETCONFA_IFINDEX_ALL,
889 						     net->ipv6.devconf_all);
890 	}
891 	rtnl_unlock();
892 
893 	return 1;
894 }
895 
896 #endif
897 
898 /* Nobody refers to this ifaddr, destroy it */
899 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
900 {
901 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
902 
903 #ifdef NET_REFCNT_DEBUG
904 	pr_debug("%s\n", __func__);
905 #endif
906 
907 	in6_dev_put(ifp->idev);
908 
909 	if (cancel_delayed_work(&ifp->dad_work))
910 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
911 			  ifp);
912 
913 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
914 		pr_warn("Freeing alive inet6 address %p\n", ifp);
915 		return;
916 	}
917 
918 	kfree_rcu(ifp, rcu);
919 }
920 
921 static void
922 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
923 {
924 	struct list_head *p;
925 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
926 
927 	/*
928 	 * Each device address list is sorted in order of scope -
929 	 * global before linklocal.
930 	 */
931 	list_for_each(p, &idev->addr_list) {
932 		struct inet6_ifaddr *ifa
933 			= list_entry(p, struct inet6_ifaddr, if_list);
934 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
935 			break;
936 	}
937 
938 	list_add_tail_rcu(&ifp->if_list, p);
939 }
940 
941 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
942 {
943 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
944 
945 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
946 }
947 
948 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
949 			       struct net_device *dev, unsigned int hash)
950 {
951 	struct inet6_ifaddr *ifp;
952 
953 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
954 		if (!net_eq(dev_net(ifp->idev->dev), net))
955 			continue;
956 		if (ipv6_addr_equal(&ifp->addr, addr)) {
957 			if (!dev || ifp->idev->dev == dev)
958 				return true;
959 		}
960 	}
961 	return false;
962 }
963 
964 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
965 {
966 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
967 	int err = 0;
968 
969 	spin_lock(&addrconf_hash_lock);
970 
971 	/* Ignore adding duplicate addresses on an interface */
972 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
973 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
974 		err = -EEXIST;
975 	} else {
976 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
977 	}
978 
979 	spin_unlock(&addrconf_hash_lock);
980 
981 	return err;
982 }
983 
984 /* On success it returns ifp with increased reference count */
985 
986 static struct inet6_ifaddr *
987 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
988 	      bool can_block, struct netlink_ext_ack *extack)
989 {
990 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
991 	int addr_type = ipv6_addr_type(cfg->pfx);
992 	struct net *net = dev_net(idev->dev);
993 	struct inet6_ifaddr *ifa = NULL;
994 	struct fib6_info *f6i = NULL;
995 	int err = 0;
996 
997 	if (addr_type == IPV6_ADDR_ANY ||
998 	    addr_type & IPV6_ADDR_MULTICAST ||
999 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1000 	     !netif_is_l3_master(idev->dev) &&
1001 	     addr_type & IPV6_ADDR_LOOPBACK))
1002 		return ERR_PTR(-EADDRNOTAVAIL);
1003 
1004 	if (idev->dead) {
1005 		err = -ENODEV;			/*XXX*/
1006 		goto out;
1007 	}
1008 
1009 	if (idev->cnf.disable_ipv6) {
1010 		err = -EACCES;
1011 		goto out;
1012 	}
1013 
1014 	/* validator notifier needs to be blocking;
1015 	 * do not call in atomic context
1016 	 */
1017 	if (can_block) {
1018 		struct in6_validator_info i6vi = {
1019 			.i6vi_addr = *cfg->pfx,
1020 			.i6vi_dev = idev,
1021 			.extack = extack,
1022 		};
1023 
1024 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1025 		err = notifier_to_errno(err);
1026 		if (err < 0)
1027 			goto out;
1028 	}
1029 
1030 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1031 	if (!ifa) {
1032 		err = -ENOBUFS;
1033 		goto out;
1034 	}
1035 
1036 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1037 	if (IS_ERR(f6i)) {
1038 		err = PTR_ERR(f6i);
1039 		f6i = NULL;
1040 		goto out;
1041 	}
1042 
1043 	if (net->ipv6.devconf_all->disable_policy ||
1044 	    idev->cnf.disable_policy)
1045 		f6i->dst_nopolicy = true;
1046 
1047 	neigh_parms_data_state_setall(idev->nd_parms);
1048 
1049 	ifa->addr = *cfg->pfx;
1050 	if (cfg->peer_pfx)
1051 		ifa->peer_addr = *cfg->peer_pfx;
1052 
1053 	spin_lock_init(&ifa->lock);
1054 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1055 	INIT_HLIST_NODE(&ifa->addr_lst);
1056 	ifa->scope = cfg->scope;
1057 	ifa->prefix_len = cfg->plen;
1058 	ifa->rt_priority = cfg->rt_priority;
1059 	ifa->flags = cfg->ifa_flags;
1060 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1061 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1062 		ifa->flags |= IFA_F_TENTATIVE;
1063 	ifa->valid_lft = cfg->valid_lft;
1064 	ifa->prefered_lft = cfg->preferred_lft;
1065 	ifa->cstamp = ifa->tstamp = jiffies;
1066 	ifa->tokenized = false;
1067 
1068 	ifa->rt = f6i;
1069 
1070 	ifa->idev = idev;
1071 	in6_dev_hold(idev);
1072 
1073 	/* For caller */
1074 	refcount_set(&ifa->refcnt, 1);
1075 
1076 	rcu_read_lock_bh();
1077 
1078 	err = ipv6_add_addr_hash(idev->dev, ifa);
1079 	if (err < 0) {
1080 		rcu_read_unlock_bh();
1081 		goto out;
1082 	}
1083 
1084 	write_lock(&idev->lock);
1085 
1086 	/* Add to inet6_dev unicast addr list. */
1087 	ipv6_link_dev_addr(idev, ifa);
1088 
1089 	if (ifa->flags&IFA_F_TEMPORARY) {
1090 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1091 		in6_ifa_hold(ifa);
1092 	}
1093 
1094 	in6_ifa_hold(ifa);
1095 	write_unlock(&idev->lock);
1096 
1097 	rcu_read_unlock_bh();
1098 
1099 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1100 out:
1101 	if (unlikely(err < 0)) {
1102 		fib6_info_release(f6i);
1103 
1104 		if (ifa) {
1105 			if (ifa->idev)
1106 				in6_dev_put(ifa->idev);
1107 			kfree(ifa);
1108 		}
1109 		ifa = ERR_PTR(err);
1110 	}
1111 
1112 	return ifa;
1113 }
1114 
1115 enum cleanup_prefix_rt_t {
1116 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1117 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1118 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1119 };
1120 
1121 /*
1122  * Check, whether the prefix for ifp would still need a prefix route
1123  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1124  * constants.
1125  *
1126  * 1) we don't purge prefix if address was not permanent.
1127  *    prefix is managed by its own lifetime.
1128  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1129  * 3) if there are no addresses, delete prefix.
1130  * 4) if there are still other permanent address(es),
1131  *    corresponding prefix is still permanent.
1132  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1133  *    don't purge the prefix, assume user space is managing it.
1134  * 6) otherwise, update prefix lifetime to the
1135  *    longest valid lifetime among the corresponding
1136  *    addresses on the device.
1137  *    Note: subsequent RA will update lifetime.
1138  **/
1139 static enum cleanup_prefix_rt_t
1140 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1141 {
1142 	struct inet6_ifaddr *ifa;
1143 	struct inet6_dev *idev = ifp->idev;
1144 	unsigned long lifetime;
1145 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1146 
1147 	*expires = jiffies;
1148 
1149 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1150 		if (ifa == ifp)
1151 			continue;
1152 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1153 				       ifp->prefix_len))
1154 			continue;
1155 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1156 			return CLEANUP_PREFIX_RT_NOP;
1157 
1158 		action = CLEANUP_PREFIX_RT_EXPIRE;
1159 
1160 		spin_lock(&ifa->lock);
1161 
1162 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1163 		/*
1164 		 * Note: Because this address is
1165 		 * not permanent, lifetime <
1166 		 * LONG_MAX / HZ here.
1167 		 */
1168 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1169 			*expires = ifa->tstamp + lifetime * HZ;
1170 		spin_unlock(&ifa->lock);
1171 	}
1172 
1173 	return action;
1174 }
1175 
1176 static void
1177 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1178 {
1179 	struct fib6_info *f6i;
1180 
1181 	f6i = addrconf_get_prefix_route(&ifp->addr,
1182 				       ifp->prefix_len,
1183 				       ifp->idev->dev,
1184 				       0, RTF_GATEWAY | RTF_DEFAULT);
1185 	if (f6i) {
1186 		if (del_rt)
1187 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1188 		else {
1189 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1190 				fib6_set_expires(f6i, expires);
1191 			fib6_info_release(f6i);
1192 		}
1193 	}
1194 }
1195 
1196 
1197 /* This function wants to get referenced ifp and releases it before return */
1198 
1199 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1200 {
1201 	int state;
1202 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1203 	unsigned long expires;
1204 
1205 	ASSERT_RTNL();
1206 
1207 	spin_lock_bh(&ifp->lock);
1208 	state = ifp->state;
1209 	ifp->state = INET6_IFADDR_STATE_DEAD;
1210 	spin_unlock_bh(&ifp->lock);
1211 
1212 	if (state == INET6_IFADDR_STATE_DEAD)
1213 		goto out;
1214 
1215 	spin_lock_bh(&addrconf_hash_lock);
1216 	hlist_del_init_rcu(&ifp->addr_lst);
1217 	spin_unlock_bh(&addrconf_hash_lock);
1218 
1219 	write_lock_bh(&ifp->idev->lock);
1220 
1221 	if (ifp->flags&IFA_F_TEMPORARY) {
1222 		list_del(&ifp->tmp_list);
1223 		if (ifp->ifpub) {
1224 			in6_ifa_put(ifp->ifpub);
1225 			ifp->ifpub = NULL;
1226 		}
1227 		__in6_ifa_put(ifp);
1228 	}
1229 
1230 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1231 		action = check_cleanup_prefix_route(ifp, &expires);
1232 
1233 	list_del_rcu(&ifp->if_list);
1234 	__in6_ifa_put(ifp);
1235 
1236 	write_unlock_bh(&ifp->idev->lock);
1237 
1238 	addrconf_del_dad_work(ifp);
1239 
1240 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1241 
1242 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1243 
1244 	if (action != CLEANUP_PREFIX_RT_NOP) {
1245 		cleanup_prefix_route(ifp, expires,
1246 			action == CLEANUP_PREFIX_RT_DEL);
1247 	}
1248 
1249 	/* clean up prefsrc entries */
1250 	rt6_remove_prefsrc(ifp);
1251 out:
1252 	in6_ifa_put(ifp);
1253 }
1254 
1255 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1256 				struct inet6_ifaddr *ift,
1257 				bool block)
1258 {
1259 	struct inet6_dev *idev = ifp->idev;
1260 	struct in6_addr addr, *tmpaddr;
1261 	unsigned long tmp_tstamp, age;
1262 	unsigned long regen_advance;
1263 	struct ifa6_config cfg;
1264 	int ret = 0;
1265 	unsigned long now = jiffies;
1266 	long max_desync_factor;
1267 	s32 cnf_temp_preferred_lft;
1268 
1269 	write_lock_bh(&idev->lock);
1270 	if (ift) {
1271 		spin_lock_bh(&ift->lock);
1272 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1273 		spin_unlock_bh(&ift->lock);
1274 		tmpaddr = &addr;
1275 	} else {
1276 		tmpaddr = NULL;
1277 	}
1278 retry:
1279 	in6_dev_hold(idev);
1280 	if (idev->cnf.use_tempaddr <= 0) {
1281 		write_unlock_bh(&idev->lock);
1282 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1283 		in6_dev_put(idev);
1284 		ret = -1;
1285 		goto out;
1286 	}
1287 	spin_lock_bh(&ifp->lock);
1288 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1289 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1290 		spin_unlock_bh(&ifp->lock);
1291 		write_unlock_bh(&idev->lock);
1292 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1293 			__func__);
1294 		in6_dev_put(idev);
1295 		ret = -1;
1296 		goto out;
1297 	}
1298 	in6_ifa_hold(ifp);
1299 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1300 	ipv6_try_regen_rndid(idev, tmpaddr);
1301 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1302 	age = (now - ifp->tstamp) / HZ;
1303 
1304 	regen_advance = idev->cnf.regen_max_retry *
1305 			idev->cnf.dad_transmits *
1306 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1307 
1308 	/* recalculate max_desync_factor each time and update
1309 	 * idev->desync_factor if it's larger
1310 	 */
1311 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1312 	max_desync_factor = min_t(__u32,
1313 				  idev->cnf.max_desync_factor,
1314 				  cnf_temp_preferred_lft - regen_advance);
1315 
1316 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1317 		if (max_desync_factor > 0) {
1318 			get_random_bytes(&idev->desync_factor,
1319 					 sizeof(idev->desync_factor));
1320 			idev->desync_factor %= max_desync_factor;
1321 		} else {
1322 			idev->desync_factor = 0;
1323 		}
1324 	}
1325 
1326 	memset(&cfg, 0, sizeof(cfg));
1327 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1328 			      idev->cnf.temp_valid_lft + age);
1329 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1330 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1331 
1332 	cfg.plen = ifp->prefix_len;
1333 	tmp_tstamp = ifp->tstamp;
1334 	spin_unlock_bh(&ifp->lock);
1335 
1336 	write_unlock_bh(&idev->lock);
1337 
1338 	/* A temporary address is created only if this calculated Preferred
1339 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1340 	 * an implementation must not create a temporary address with a zero
1341 	 * Preferred Lifetime.
1342 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1343 	 * temporary addresses being generated.
1344 	 */
1345 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1346 	if (cfg.preferred_lft <= regen_advance + age) {
1347 		in6_ifa_put(ifp);
1348 		in6_dev_put(idev);
1349 		ret = -1;
1350 		goto out;
1351 	}
1352 
1353 	cfg.ifa_flags = IFA_F_TEMPORARY;
1354 	/* set in addrconf_prefix_rcv() */
1355 	if (ifp->flags & IFA_F_OPTIMISTIC)
1356 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1357 
1358 	cfg.pfx = &addr;
1359 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1360 
1361 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1362 	if (IS_ERR(ift)) {
1363 		in6_ifa_put(ifp);
1364 		in6_dev_put(idev);
1365 		pr_info("%s: retry temporary address regeneration\n", __func__);
1366 		tmpaddr = &addr;
1367 		write_lock_bh(&idev->lock);
1368 		goto retry;
1369 	}
1370 
1371 	spin_lock_bh(&ift->lock);
1372 	ift->ifpub = ifp;
1373 	ift->cstamp = now;
1374 	ift->tstamp = tmp_tstamp;
1375 	spin_unlock_bh(&ift->lock);
1376 
1377 	addrconf_dad_start(ift);
1378 	in6_ifa_put(ift);
1379 	in6_dev_put(idev);
1380 out:
1381 	return ret;
1382 }
1383 
1384 /*
1385  *	Choose an appropriate source address (RFC3484)
1386  */
1387 enum {
1388 	IPV6_SADDR_RULE_INIT = 0,
1389 	IPV6_SADDR_RULE_LOCAL,
1390 	IPV6_SADDR_RULE_SCOPE,
1391 	IPV6_SADDR_RULE_PREFERRED,
1392 #ifdef CONFIG_IPV6_MIP6
1393 	IPV6_SADDR_RULE_HOA,
1394 #endif
1395 	IPV6_SADDR_RULE_OIF,
1396 	IPV6_SADDR_RULE_LABEL,
1397 	IPV6_SADDR_RULE_PRIVACY,
1398 	IPV6_SADDR_RULE_ORCHID,
1399 	IPV6_SADDR_RULE_PREFIX,
1400 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1401 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1402 #endif
1403 	IPV6_SADDR_RULE_MAX
1404 };
1405 
1406 struct ipv6_saddr_score {
1407 	int			rule;
1408 	int			addr_type;
1409 	struct inet6_ifaddr	*ifa;
1410 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1411 	int			scopedist;
1412 	int			matchlen;
1413 };
1414 
1415 struct ipv6_saddr_dst {
1416 	const struct in6_addr *addr;
1417 	int ifindex;
1418 	int scope;
1419 	int label;
1420 	unsigned int prefs;
1421 };
1422 
1423 static inline int ipv6_saddr_preferred(int type)
1424 {
1425 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1426 		return 1;
1427 	return 0;
1428 }
1429 
1430 static bool ipv6_use_optimistic_addr(struct net *net,
1431 				     struct inet6_dev *idev)
1432 {
1433 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1434 	if (!idev)
1435 		return false;
1436 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1437 		return false;
1438 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1439 		return false;
1440 
1441 	return true;
1442 #else
1443 	return false;
1444 #endif
1445 }
1446 
1447 static bool ipv6_allow_optimistic_dad(struct net *net,
1448 				      struct inet6_dev *idev)
1449 {
1450 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1451 	if (!idev)
1452 		return false;
1453 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1454 		return false;
1455 
1456 	return true;
1457 #else
1458 	return false;
1459 #endif
1460 }
1461 
1462 static int ipv6_get_saddr_eval(struct net *net,
1463 			       struct ipv6_saddr_score *score,
1464 			       struct ipv6_saddr_dst *dst,
1465 			       int i)
1466 {
1467 	int ret;
1468 
1469 	if (i <= score->rule) {
1470 		switch (i) {
1471 		case IPV6_SADDR_RULE_SCOPE:
1472 			ret = score->scopedist;
1473 			break;
1474 		case IPV6_SADDR_RULE_PREFIX:
1475 			ret = score->matchlen;
1476 			break;
1477 		default:
1478 			ret = !!test_bit(i, score->scorebits);
1479 		}
1480 		goto out;
1481 	}
1482 
1483 	switch (i) {
1484 	case IPV6_SADDR_RULE_INIT:
1485 		/* Rule 0: remember if hiscore is not ready yet */
1486 		ret = !!score->ifa;
1487 		break;
1488 	case IPV6_SADDR_RULE_LOCAL:
1489 		/* Rule 1: Prefer same address */
1490 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1491 		break;
1492 	case IPV6_SADDR_RULE_SCOPE:
1493 		/* Rule 2: Prefer appropriate scope
1494 		 *
1495 		 *      ret
1496 		 *       ^
1497 		 *    -1 |  d 15
1498 		 *    ---+--+-+---> scope
1499 		 *       |
1500 		 *       |             d is scope of the destination.
1501 		 *  B-d  |  \
1502 		 *       |   \      <- smaller scope is better if
1503 		 *  B-15 |    \        if scope is enough for destination.
1504 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1505 		 * d-C-1 | /
1506 		 *       |/         <- greater is better
1507 		 *   -C  /             if scope is not enough for destination.
1508 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1509 		 *
1510 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1511 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1512 		 * Assume B = 0 and we get C > 29.
1513 		 */
1514 		ret = __ipv6_addr_src_scope(score->addr_type);
1515 		if (ret >= dst->scope)
1516 			ret = -ret;
1517 		else
1518 			ret -= 128;	/* 30 is enough */
1519 		score->scopedist = ret;
1520 		break;
1521 	case IPV6_SADDR_RULE_PREFERRED:
1522 	    {
1523 		/* Rule 3: Avoid deprecated and optimistic addresses */
1524 		u8 avoid = IFA_F_DEPRECATED;
1525 
1526 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1527 			avoid |= IFA_F_OPTIMISTIC;
1528 		ret = ipv6_saddr_preferred(score->addr_type) ||
1529 		      !(score->ifa->flags & avoid);
1530 		break;
1531 	    }
1532 #ifdef CONFIG_IPV6_MIP6
1533 	case IPV6_SADDR_RULE_HOA:
1534 	    {
1535 		/* Rule 4: Prefer home address */
1536 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1537 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1538 		break;
1539 	    }
1540 #endif
1541 	case IPV6_SADDR_RULE_OIF:
1542 		/* Rule 5: Prefer outgoing interface */
1543 		ret = (!dst->ifindex ||
1544 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1545 		break;
1546 	case IPV6_SADDR_RULE_LABEL:
1547 		/* Rule 6: Prefer matching label */
1548 		ret = ipv6_addr_label(net,
1549 				      &score->ifa->addr, score->addr_type,
1550 				      score->ifa->idev->dev->ifindex) == dst->label;
1551 		break;
1552 	case IPV6_SADDR_RULE_PRIVACY:
1553 	    {
1554 		/* Rule 7: Prefer public address
1555 		 * Note: prefer temporary address if use_tempaddr >= 2
1556 		 */
1557 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1558 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1559 				score->ifa->idev->cnf.use_tempaddr >= 2;
1560 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1561 		break;
1562 	    }
1563 	case IPV6_SADDR_RULE_ORCHID:
1564 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1565 		 *	    non-ORCHID vs non-ORCHID
1566 		 */
1567 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1568 			ipv6_addr_orchid(dst->addr));
1569 		break;
1570 	case IPV6_SADDR_RULE_PREFIX:
1571 		/* Rule 8: Use longest matching prefix */
1572 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1573 		if (ret > score->ifa->prefix_len)
1574 			ret = score->ifa->prefix_len;
1575 		score->matchlen = ret;
1576 		break;
1577 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1578 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1579 		/* Optimistic addresses still have lower precedence than other
1580 		 * preferred addresses.
1581 		 */
1582 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1583 		break;
1584 #endif
1585 	default:
1586 		ret = 0;
1587 	}
1588 
1589 	if (ret)
1590 		__set_bit(i, score->scorebits);
1591 	score->rule = i;
1592 out:
1593 	return ret;
1594 }
1595 
1596 static int __ipv6_dev_get_saddr(struct net *net,
1597 				struct ipv6_saddr_dst *dst,
1598 				struct inet6_dev *idev,
1599 				struct ipv6_saddr_score *scores,
1600 				int hiscore_idx)
1601 {
1602 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1603 
1604 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1605 		int i;
1606 
1607 		/*
1608 		 * - Tentative Address (RFC2462 section 5.4)
1609 		 *  - A tentative address is not considered
1610 		 *    "assigned to an interface" in the traditional
1611 		 *    sense, unless it is also flagged as optimistic.
1612 		 * - Candidate Source Address (section 4)
1613 		 *  - In any case, anycast addresses, multicast
1614 		 *    addresses, and the unspecified address MUST
1615 		 *    NOT be included in a candidate set.
1616 		 */
1617 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1618 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1619 			continue;
1620 
1621 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1622 
1623 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1624 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1625 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1626 					    idev->dev->name);
1627 			continue;
1628 		}
1629 
1630 		score->rule = -1;
1631 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1632 
1633 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1634 			int minihiscore, miniscore;
1635 
1636 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1637 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1638 
1639 			if (minihiscore > miniscore) {
1640 				if (i == IPV6_SADDR_RULE_SCOPE &&
1641 				    score->scopedist > 0) {
1642 					/*
1643 					 * special case:
1644 					 * each remaining entry
1645 					 * has too small (not enough)
1646 					 * scope, because ifa entries
1647 					 * are sorted by their scope
1648 					 * values.
1649 					 */
1650 					goto out;
1651 				}
1652 				break;
1653 			} else if (minihiscore < miniscore) {
1654 				swap(hiscore, score);
1655 				hiscore_idx = 1 - hiscore_idx;
1656 
1657 				/* restore our iterator */
1658 				score->ifa = hiscore->ifa;
1659 
1660 				break;
1661 			}
1662 		}
1663 	}
1664 out:
1665 	return hiscore_idx;
1666 }
1667 
1668 static int ipv6_get_saddr_master(struct net *net,
1669 				 const struct net_device *dst_dev,
1670 				 const struct net_device *master,
1671 				 struct ipv6_saddr_dst *dst,
1672 				 struct ipv6_saddr_score *scores,
1673 				 int hiscore_idx)
1674 {
1675 	struct inet6_dev *idev;
1676 
1677 	idev = __in6_dev_get(dst_dev);
1678 	if (idev)
1679 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1680 						   scores, hiscore_idx);
1681 
1682 	idev = __in6_dev_get(master);
1683 	if (idev)
1684 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1685 						   scores, hiscore_idx);
1686 
1687 	return hiscore_idx;
1688 }
1689 
1690 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1691 		       const struct in6_addr *daddr, unsigned int prefs,
1692 		       struct in6_addr *saddr)
1693 {
1694 	struct ipv6_saddr_score scores[2], *hiscore;
1695 	struct ipv6_saddr_dst dst;
1696 	struct inet6_dev *idev;
1697 	struct net_device *dev;
1698 	int dst_type;
1699 	bool use_oif_addr = false;
1700 	int hiscore_idx = 0;
1701 	int ret = 0;
1702 
1703 	dst_type = __ipv6_addr_type(daddr);
1704 	dst.addr = daddr;
1705 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1706 	dst.scope = __ipv6_addr_src_scope(dst_type);
1707 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1708 	dst.prefs = prefs;
1709 
1710 	scores[hiscore_idx].rule = -1;
1711 	scores[hiscore_idx].ifa = NULL;
1712 
1713 	rcu_read_lock();
1714 
1715 	/* Candidate Source Address (section 4)
1716 	 *  - multicast and link-local destination address,
1717 	 *    the set of candidate source address MUST only
1718 	 *    include addresses assigned to interfaces
1719 	 *    belonging to the same link as the outgoing
1720 	 *    interface.
1721 	 * (- For site-local destination addresses, the
1722 	 *    set of candidate source addresses MUST only
1723 	 *    include addresses assigned to interfaces
1724 	 *    belonging to the same site as the outgoing
1725 	 *    interface.)
1726 	 *  - "It is RECOMMENDED that the candidate source addresses
1727 	 *    be the set of unicast addresses assigned to the
1728 	 *    interface that will be used to send to the destination
1729 	 *    (the 'outgoing' interface)." (RFC 6724)
1730 	 */
1731 	if (dst_dev) {
1732 		idev = __in6_dev_get(dst_dev);
1733 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1734 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1735 		    (idev && idev->cnf.use_oif_addrs_only)) {
1736 			use_oif_addr = true;
1737 		}
1738 	}
1739 
1740 	if (use_oif_addr) {
1741 		if (idev)
1742 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1743 	} else {
1744 		const struct net_device *master;
1745 		int master_idx = 0;
1746 
1747 		/* if dst_dev exists and is enslaved to an L3 device, then
1748 		 * prefer addresses from dst_dev and then the master over
1749 		 * any other enslaved devices in the L3 domain.
1750 		 */
1751 		master = l3mdev_master_dev_rcu(dst_dev);
1752 		if (master) {
1753 			master_idx = master->ifindex;
1754 
1755 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1756 							    master, &dst,
1757 							    scores, hiscore_idx);
1758 
1759 			if (scores[hiscore_idx].ifa)
1760 				goto out;
1761 		}
1762 
1763 		for_each_netdev_rcu(net, dev) {
1764 			/* only consider addresses on devices in the
1765 			 * same L3 domain
1766 			 */
1767 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1768 				continue;
1769 			idev = __in6_dev_get(dev);
1770 			if (!idev)
1771 				continue;
1772 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1773 		}
1774 	}
1775 
1776 out:
1777 	hiscore = &scores[hiscore_idx];
1778 	if (!hiscore->ifa)
1779 		ret = -EADDRNOTAVAIL;
1780 	else
1781 		*saddr = hiscore->ifa->addr;
1782 
1783 	rcu_read_unlock();
1784 	return ret;
1785 }
1786 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1787 
1788 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1789 		      u32 banned_flags)
1790 {
1791 	struct inet6_ifaddr *ifp;
1792 	int err = -EADDRNOTAVAIL;
1793 
1794 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1795 		if (ifp->scope > IFA_LINK)
1796 			break;
1797 		if (ifp->scope == IFA_LINK &&
1798 		    !(ifp->flags & banned_flags)) {
1799 			*addr = ifp->addr;
1800 			err = 0;
1801 			break;
1802 		}
1803 	}
1804 	return err;
1805 }
1806 
1807 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1808 		    u32 banned_flags)
1809 {
1810 	struct inet6_dev *idev;
1811 	int err = -EADDRNOTAVAIL;
1812 
1813 	rcu_read_lock();
1814 	idev = __in6_dev_get(dev);
1815 	if (idev) {
1816 		read_lock_bh(&idev->lock);
1817 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1818 		read_unlock_bh(&idev->lock);
1819 	}
1820 	rcu_read_unlock();
1821 	return err;
1822 }
1823 
1824 static int ipv6_count_addresses(const struct inet6_dev *idev)
1825 {
1826 	const struct inet6_ifaddr *ifp;
1827 	int cnt = 0;
1828 
1829 	rcu_read_lock();
1830 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1831 		cnt++;
1832 	rcu_read_unlock();
1833 	return cnt;
1834 }
1835 
1836 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1837 		  const struct net_device *dev, int strict)
1838 {
1839 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1840 				       strict, IFA_F_TENTATIVE);
1841 }
1842 EXPORT_SYMBOL(ipv6_chk_addr);
1843 
1844 /* device argument is used to find the L3 domain of interest. If
1845  * skip_dev_check is set, then the ifp device is not checked against
1846  * the passed in dev argument. So the 2 cases for addresses checks are:
1847  *   1. does the address exist in the L3 domain that dev is part of
1848  *      (skip_dev_check = true), or
1849  *
1850  *   2. does the address exist on the specific device
1851  *      (skip_dev_check = false)
1852  */
1853 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1854 			    const struct net_device *dev, bool skip_dev_check,
1855 			    int strict, u32 banned_flags)
1856 {
1857 	unsigned int hash = inet6_addr_hash(net, addr);
1858 	const struct net_device *l3mdev;
1859 	struct inet6_ifaddr *ifp;
1860 	u32 ifp_flags;
1861 
1862 	rcu_read_lock();
1863 
1864 	l3mdev = l3mdev_master_dev_rcu(dev);
1865 	if (skip_dev_check)
1866 		dev = NULL;
1867 
1868 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1869 		if (!net_eq(dev_net(ifp->idev->dev), net))
1870 			continue;
1871 
1872 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1873 			continue;
1874 
1875 		/* Decouple optimistic from tentative for evaluation here.
1876 		 * Ban optimistic addresses explicitly, when required.
1877 		 */
1878 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1879 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1880 			    : ifp->flags;
1881 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1882 		    !(ifp_flags&banned_flags) &&
1883 		    (!dev || ifp->idev->dev == dev ||
1884 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1885 			rcu_read_unlock();
1886 			return 1;
1887 		}
1888 	}
1889 
1890 	rcu_read_unlock();
1891 	return 0;
1892 }
1893 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1894 
1895 
1896 /* Compares an address/prefix_len with addresses on device @dev.
1897  * If one is found it returns true.
1898  */
1899 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1900 	const unsigned int prefix_len, struct net_device *dev)
1901 {
1902 	const struct inet6_ifaddr *ifa;
1903 	const struct inet6_dev *idev;
1904 	bool ret = false;
1905 
1906 	rcu_read_lock();
1907 	idev = __in6_dev_get(dev);
1908 	if (idev) {
1909 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1910 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1911 			if (ret)
1912 				break;
1913 		}
1914 	}
1915 	rcu_read_unlock();
1916 
1917 	return ret;
1918 }
1919 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1920 
1921 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1922 {
1923 	const struct inet6_ifaddr *ifa;
1924 	const struct inet6_dev *idev;
1925 	int	onlink;
1926 
1927 	onlink = 0;
1928 	rcu_read_lock();
1929 	idev = __in6_dev_get(dev);
1930 	if (idev) {
1931 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1932 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1933 						   ifa->prefix_len);
1934 			if (onlink)
1935 				break;
1936 		}
1937 	}
1938 	rcu_read_unlock();
1939 	return onlink;
1940 }
1941 EXPORT_SYMBOL(ipv6_chk_prefix);
1942 
1943 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1944 				     struct net_device *dev, int strict)
1945 {
1946 	unsigned int hash = inet6_addr_hash(net, addr);
1947 	struct inet6_ifaddr *ifp, *result = NULL;
1948 
1949 	rcu_read_lock();
1950 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1951 		if (!net_eq(dev_net(ifp->idev->dev), net))
1952 			continue;
1953 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1954 			if (!dev || ifp->idev->dev == dev ||
1955 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1956 				result = ifp;
1957 				in6_ifa_hold(ifp);
1958 				break;
1959 			}
1960 		}
1961 	}
1962 	rcu_read_unlock();
1963 
1964 	return result;
1965 }
1966 
1967 /* Gets referenced address, destroys ifaddr */
1968 
1969 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1970 {
1971 	if (dad_failed)
1972 		ifp->flags |= IFA_F_DADFAILED;
1973 
1974 	if (ifp->flags&IFA_F_TEMPORARY) {
1975 		struct inet6_ifaddr *ifpub;
1976 		spin_lock_bh(&ifp->lock);
1977 		ifpub = ifp->ifpub;
1978 		if (ifpub) {
1979 			in6_ifa_hold(ifpub);
1980 			spin_unlock_bh(&ifp->lock);
1981 			ipv6_create_tempaddr(ifpub, ifp, true);
1982 			in6_ifa_put(ifpub);
1983 		} else {
1984 			spin_unlock_bh(&ifp->lock);
1985 		}
1986 		ipv6_del_addr(ifp);
1987 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1988 		spin_lock_bh(&ifp->lock);
1989 		addrconf_del_dad_work(ifp);
1990 		ifp->flags |= IFA_F_TENTATIVE;
1991 		if (dad_failed)
1992 			ifp->flags &= ~IFA_F_OPTIMISTIC;
1993 		spin_unlock_bh(&ifp->lock);
1994 		if (dad_failed)
1995 			ipv6_ifa_notify(0, ifp);
1996 		in6_ifa_put(ifp);
1997 	} else {
1998 		ipv6_del_addr(ifp);
1999 	}
2000 }
2001 
2002 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2003 {
2004 	int err = -ENOENT;
2005 
2006 	spin_lock_bh(&ifp->lock);
2007 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2008 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2009 		err = 0;
2010 	}
2011 	spin_unlock_bh(&ifp->lock);
2012 
2013 	return err;
2014 }
2015 
2016 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2017 {
2018 	struct inet6_dev *idev = ifp->idev;
2019 	struct net *net = dev_net(ifp->idev->dev);
2020 
2021 	if (addrconf_dad_end(ifp)) {
2022 		in6_ifa_put(ifp);
2023 		return;
2024 	}
2025 
2026 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2027 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2028 
2029 	spin_lock_bh(&ifp->lock);
2030 
2031 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2032 		struct in6_addr new_addr;
2033 		struct inet6_ifaddr *ifp2;
2034 		int retries = ifp->stable_privacy_retry + 1;
2035 		struct ifa6_config cfg = {
2036 			.pfx = &new_addr,
2037 			.plen = ifp->prefix_len,
2038 			.ifa_flags = ifp->flags,
2039 			.valid_lft = ifp->valid_lft,
2040 			.preferred_lft = ifp->prefered_lft,
2041 			.scope = ifp->scope,
2042 		};
2043 
2044 		if (retries > net->ipv6.sysctl.idgen_retries) {
2045 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2046 					     ifp->idev->dev->name);
2047 			goto errdad;
2048 		}
2049 
2050 		new_addr = ifp->addr;
2051 		if (ipv6_generate_stable_address(&new_addr, retries,
2052 						 idev))
2053 			goto errdad;
2054 
2055 		spin_unlock_bh(&ifp->lock);
2056 
2057 		if (idev->cnf.max_addresses &&
2058 		    ipv6_count_addresses(idev) >=
2059 		    idev->cnf.max_addresses)
2060 			goto lock_errdad;
2061 
2062 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2063 				     ifp->idev->dev->name);
2064 
2065 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2066 		if (IS_ERR(ifp2))
2067 			goto lock_errdad;
2068 
2069 		spin_lock_bh(&ifp2->lock);
2070 		ifp2->stable_privacy_retry = retries;
2071 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2072 		spin_unlock_bh(&ifp2->lock);
2073 
2074 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2075 		in6_ifa_put(ifp2);
2076 lock_errdad:
2077 		spin_lock_bh(&ifp->lock);
2078 	}
2079 
2080 errdad:
2081 	/* transition from _POSTDAD to _ERRDAD */
2082 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2083 	spin_unlock_bh(&ifp->lock);
2084 
2085 	addrconf_mod_dad_work(ifp, 0);
2086 	in6_ifa_put(ifp);
2087 }
2088 
2089 /* Join to solicited addr multicast group.
2090  * caller must hold RTNL */
2091 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2092 {
2093 	struct in6_addr maddr;
2094 
2095 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2096 		return;
2097 
2098 	addrconf_addr_solict_mult(addr, &maddr);
2099 	ipv6_dev_mc_inc(dev, &maddr);
2100 }
2101 
2102 /* caller must hold RTNL */
2103 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2104 {
2105 	struct in6_addr maddr;
2106 
2107 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2108 		return;
2109 
2110 	addrconf_addr_solict_mult(addr, &maddr);
2111 	__ipv6_dev_mc_dec(idev, &maddr);
2112 }
2113 
2114 /* caller must hold RTNL */
2115 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2116 {
2117 	struct in6_addr addr;
2118 
2119 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2120 		return;
2121 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2122 	if (ipv6_addr_any(&addr))
2123 		return;
2124 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2125 }
2126 
2127 /* caller must hold RTNL */
2128 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2129 {
2130 	struct in6_addr addr;
2131 
2132 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2133 		return;
2134 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2135 	if (ipv6_addr_any(&addr))
2136 		return;
2137 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2138 }
2139 
2140 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2141 {
2142 	switch (dev->addr_len) {
2143 	case ETH_ALEN:
2144 		memcpy(eui, dev->dev_addr, 3);
2145 		eui[3] = 0xFF;
2146 		eui[4] = 0xFE;
2147 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2148 		break;
2149 	case EUI64_ADDR_LEN:
2150 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2151 		eui[0] ^= 2;
2152 		break;
2153 	default:
2154 		return -1;
2155 	}
2156 
2157 	return 0;
2158 }
2159 
2160 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2161 {
2162 	union fwnet_hwaddr *ha;
2163 
2164 	if (dev->addr_len != FWNET_ALEN)
2165 		return -1;
2166 
2167 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2168 
2169 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2170 	eui[0] ^= 2;
2171 	return 0;
2172 }
2173 
2174 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2175 {
2176 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2177 	if (dev->addr_len != ARCNET_ALEN)
2178 		return -1;
2179 	memset(eui, 0, 7);
2180 	eui[7] = *(u8 *)dev->dev_addr;
2181 	return 0;
2182 }
2183 
2184 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2185 {
2186 	if (dev->addr_len != INFINIBAND_ALEN)
2187 		return -1;
2188 	memcpy(eui, dev->dev_addr + 12, 8);
2189 	eui[0] |= 2;
2190 	return 0;
2191 }
2192 
2193 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2194 {
2195 	if (addr == 0)
2196 		return -1;
2197 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2198 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2199 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2200 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2201 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2202 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2203 	eui[1] = 0;
2204 	eui[2] = 0x5E;
2205 	eui[3] = 0xFE;
2206 	memcpy(eui + 4, &addr, 4);
2207 	return 0;
2208 }
2209 
2210 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2211 {
2212 	if (dev->priv_flags & IFF_ISATAP)
2213 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2214 	return -1;
2215 }
2216 
2217 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2218 {
2219 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2220 }
2221 
2222 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2223 {
2224 	memcpy(eui, dev->perm_addr, 3);
2225 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2226 	eui[3] = 0xFF;
2227 	eui[4] = 0xFE;
2228 	eui[0] ^= 2;
2229 	return 0;
2230 }
2231 
2232 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2233 {
2234 	switch (dev->type) {
2235 	case ARPHRD_ETHER:
2236 	case ARPHRD_FDDI:
2237 		return addrconf_ifid_eui48(eui, dev);
2238 	case ARPHRD_ARCNET:
2239 		return addrconf_ifid_arcnet(eui, dev);
2240 	case ARPHRD_INFINIBAND:
2241 		return addrconf_ifid_infiniband(eui, dev);
2242 	case ARPHRD_SIT:
2243 		return addrconf_ifid_sit(eui, dev);
2244 	case ARPHRD_IPGRE:
2245 	case ARPHRD_TUNNEL:
2246 		return addrconf_ifid_gre(eui, dev);
2247 	case ARPHRD_6LOWPAN:
2248 		return addrconf_ifid_6lowpan(eui, dev);
2249 	case ARPHRD_IEEE1394:
2250 		return addrconf_ifid_ieee1394(eui, dev);
2251 	case ARPHRD_TUNNEL6:
2252 	case ARPHRD_IP6GRE:
2253 	case ARPHRD_RAWIP:
2254 		return addrconf_ifid_ip6tnl(eui, dev);
2255 	}
2256 	return -1;
2257 }
2258 
2259 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2260 {
2261 	int err = -1;
2262 	struct inet6_ifaddr *ifp;
2263 
2264 	read_lock_bh(&idev->lock);
2265 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2266 		if (ifp->scope > IFA_LINK)
2267 			break;
2268 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2269 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2270 			err = 0;
2271 			break;
2272 		}
2273 	}
2274 	read_unlock_bh(&idev->lock);
2275 	return err;
2276 }
2277 
2278 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2279 static void ipv6_regen_rndid(struct inet6_dev *idev)
2280 {
2281 regen:
2282 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2283 	idev->rndid[0] &= ~0x02;
2284 
2285 	/*
2286 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2287 	 * check if generated address is not inappropriate
2288 	 *
2289 	 *  - Reserved subnet anycast (RFC 2526)
2290 	 *	11111101 11....11 1xxxxxxx
2291 	 *  - ISATAP (RFC4214) 6.1
2292 	 *	00-00-5E-FE-xx-xx-xx-xx
2293 	 *  - value 0
2294 	 *  - XXX: already assigned to an address on the device
2295 	 */
2296 	if (idev->rndid[0] == 0xfd &&
2297 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2298 	    (idev->rndid[7]&0x80))
2299 		goto regen;
2300 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2301 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2302 			goto regen;
2303 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2304 			goto regen;
2305 	}
2306 }
2307 
2308 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2309 {
2310 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2311 		ipv6_regen_rndid(idev);
2312 }
2313 
2314 /*
2315  *	Add prefix route.
2316  */
2317 
2318 static void
2319 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2320 		      struct net_device *dev, unsigned long expires,
2321 		      u32 flags, gfp_t gfp_flags)
2322 {
2323 	struct fib6_config cfg = {
2324 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2325 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2326 		.fc_ifindex = dev->ifindex,
2327 		.fc_expires = expires,
2328 		.fc_dst_len = plen,
2329 		.fc_flags = RTF_UP | flags,
2330 		.fc_nlinfo.nl_net = dev_net(dev),
2331 		.fc_protocol = RTPROT_KERNEL,
2332 		.fc_type = RTN_UNICAST,
2333 	};
2334 
2335 	cfg.fc_dst = *pfx;
2336 
2337 	/* Prevent useless cloning on PtP SIT.
2338 	   This thing is done here expecting that the whole
2339 	   class of non-broadcast devices need not cloning.
2340 	 */
2341 #if IS_ENABLED(CONFIG_IPV6_SIT)
2342 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2343 		cfg.fc_flags |= RTF_NONEXTHOP;
2344 #endif
2345 
2346 	ip6_route_add(&cfg, gfp_flags, NULL);
2347 }
2348 
2349 
2350 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2351 						  int plen,
2352 						  const struct net_device *dev,
2353 						  u32 flags, u32 noflags)
2354 {
2355 	struct fib6_node *fn;
2356 	struct fib6_info *rt = NULL;
2357 	struct fib6_table *table;
2358 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2359 
2360 	table = fib6_get_table(dev_net(dev), tb_id);
2361 	if (!table)
2362 		return NULL;
2363 
2364 	rcu_read_lock();
2365 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2366 	if (!fn)
2367 		goto out;
2368 
2369 	for_each_fib6_node_rt_rcu(fn) {
2370 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
2371 			continue;
2372 		if ((rt->fib6_flags & flags) != flags)
2373 			continue;
2374 		if ((rt->fib6_flags & noflags) != 0)
2375 			continue;
2376 		if (!fib6_info_hold_safe(rt))
2377 			continue;
2378 		break;
2379 	}
2380 out:
2381 	rcu_read_unlock();
2382 	return rt;
2383 }
2384 
2385 
2386 /* Create "default" multicast route to the interface */
2387 
2388 static void addrconf_add_mroute(struct net_device *dev)
2389 {
2390 	struct fib6_config cfg = {
2391 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2392 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2393 		.fc_ifindex = dev->ifindex,
2394 		.fc_dst_len = 8,
2395 		.fc_flags = RTF_UP,
2396 		.fc_type = RTN_UNICAST,
2397 		.fc_nlinfo.nl_net = dev_net(dev),
2398 	};
2399 
2400 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2401 
2402 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2403 }
2404 
2405 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2406 {
2407 	struct inet6_dev *idev;
2408 
2409 	ASSERT_RTNL();
2410 
2411 	idev = ipv6_find_idev(dev);
2412 	if (!idev)
2413 		return ERR_PTR(-ENOBUFS);
2414 
2415 	if (idev->cnf.disable_ipv6)
2416 		return ERR_PTR(-EACCES);
2417 
2418 	/* Add default multicast route */
2419 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2420 		addrconf_add_mroute(dev);
2421 
2422 	return idev;
2423 }
2424 
2425 static void manage_tempaddrs(struct inet6_dev *idev,
2426 			     struct inet6_ifaddr *ifp,
2427 			     __u32 valid_lft, __u32 prefered_lft,
2428 			     bool create, unsigned long now)
2429 {
2430 	u32 flags;
2431 	struct inet6_ifaddr *ift;
2432 
2433 	read_lock_bh(&idev->lock);
2434 	/* update all temporary addresses in the list */
2435 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2436 		int age, max_valid, max_prefered;
2437 
2438 		if (ifp != ift->ifpub)
2439 			continue;
2440 
2441 		/* RFC 4941 section 3.3:
2442 		 * If a received option will extend the lifetime of a public
2443 		 * address, the lifetimes of temporary addresses should
2444 		 * be extended, subject to the overall constraint that no
2445 		 * temporary addresses should ever remain "valid" or "preferred"
2446 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2447 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2448 		 */
2449 		age = (now - ift->cstamp) / HZ;
2450 		max_valid = idev->cnf.temp_valid_lft - age;
2451 		if (max_valid < 0)
2452 			max_valid = 0;
2453 
2454 		max_prefered = idev->cnf.temp_prefered_lft -
2455 			       idev->desync_factor - age;
2456 		if (max_prefered < 0)
2457 			max_prefered = 0;
2458 
2459 		if (valid_lft > max_valid)
2460 			valid_lft = max_valid;
2461 
2462 		if (prefered_lft > max_prefered)
2463 			prefered_lft = max_prefered;
2464 
2465 		spin_lock(&ift->lock);
2466 		flags = ift->flags;
2467 		ift->valid_lft = valid_lft;
2468 		ift->prefered_lft = prefered_lft;
2469 		ift->tstamp = now;
2470 		if (prefered_lft > 0)
2471 			ift->flags &= ~IFA_F_DEPRECATED;
2472 
2473 		spin_unlock(&ift->lock);
2474 		if (!(flags&IFA_F_TENTATIVE))
2475 			ipv6_ifa_notify(0, ift);
2476 	}
2477 
2478 	if ((create || list_empty(&idev->tempaddr_list)) &&
2479 	    idev->cnf.use_tempaddr > 0) {
2480 		/* When a new public address is created as described
2481 		 * in [ADDRCONF], also create a new temporary address.
2482 		 * Also create a temporary address if it's enabled but
2483 		 * no temporary address currently exists.
2484 		 */
2485 		read_unlock_bh(&idev->lock);
2486 		ipv6_create_tempaddr(ifp, NULL, false);
2487 	} else {
2488 		read_unlock_bh(&idev->lock);
2489 	}
2490 }
2491 
2492 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2493 {
2494 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2495 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2496 }
2497 
2498 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2499 				 const struct prefix_info *pinfo,
2500 				 struct inet6_dev *in6_dev,
2501 				 const struct in6_addr *addr, int addr_type,
2502 				 u32 addr_flags, bool sllao, bool tokenized,
2503 				 __u32 valid_lft, u32 prefered_lft)
2504 {
2505 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2506 	int create = 0, update_lft = 0;
2507 
2508 	if (!ifp && valid_lft) {
2509 		int max_addresses = in6_dev->cnf.max_addresses;
2510 		struct ifa6_config cfg = {
2511 			.pfx = addr,
2512 			.plen = pinfo->prefix_len,
2513 			.ifa_flags = addr_flags,
2514 			.valid_lft = valid_lft,
2515 			.preferred_lft = prefered_lft,
2516 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2517 		};
2518 
2519 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2520 		if ((net->ipv6.devconf_all->optimistic_dad ||
2521 		     in6_dev->cnf.optimistic_dad) &&
2522 		    !net->ipv6.devconf_all->forwarding && sllao)
2523 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2524 #endif
2525 
2526 		/* Do not allow to create too much of autoconfigured
2527 		 * addresses; this would be too easy way to crash kernel.
2528 		 */
2529 		if (!max_addresses ||
2530 		    ipv6_count_addresses(in6_dev) < max_addresses)
2531 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2532 
2533 		if (IS_ERR_OR_NULL(ifp))
2534 			return -1;
2535 
2536 		create = 1;
2537 		spin_lock_bh(&ifp->lock);
2538 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2539 		ifp->cstamp = jiffies;
2540 		ifp->tokenized = tokenized;
2541 		spin_unlock_bh(&ifp->lock);
2542 		addrconf_dad_start(ifp);
2543 	}
2544 
2545 	if (ifp) {
2546 		u32 flags;
2547 		unsigned long now;
2548 		u32 stored_lft;
2549 
2550 		/* update lifetime (RFC2462 5.5.3 e) */
2551 		spin_lock_bh(&ifp->lock);
2552 		now = jiffies;
2553 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2554 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2555 		else
2556 			stored_lft = 0;
2557 		if (!create && stored_lft) {
2558 			const u32 minimum_lft = min_t(u32,
2559 				stored_lft, MIN_VALID_LIFETIME);
2560 			valid_lft = max(valid_lft, minimum_lft);
2561 
2562 			/* RFC4862 Section 5.5.3e:
2563 			 * "Note that the preferred lifetime of the
2564 			 *  corresponding address is always reset to
2565 			 *  the Preferred Lifetime in the received
2566 			 *  Prefix Information option, regardless of
2567 			 *  whether the valid lifetime is also reset or
2568 			 *  ignored."
2569 			 *
2570 			 * So we should always update prefered_lft here.
2571 			 */
2572 			update_lft = 1;
2573 		}
2574 
2575 		if (update_lft) {
2576 			ifp->valid_lft = valid_lft;
2577 			ifp->prefered_lft = prefered_lft;
2578 			ifp->tstamp = now;
2579 			flags = ifp->flags;
2580 			ifp->flags &= ~IFA_F_DEPRECATED;
2581 			spin_unlock_bh(&ifp->lock);
2582 
2583 			if (!(flags&IFA_F_TENTATIVE))
2584 				ipv6_ifa_notify(0, ifp);
2585 		} else
2586 			spin_unlock_bh(&ifp->lock);
2587 
2588 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2589 				 create, now);
2590 
2591 		in6_ifa_put(ifp);
2592 		addrconf_verify();
2593 	}
2594 
2595 	return 0;
2596 }
2597 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2598 
2599 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2600 {
2601 	struct prefix_info *pinfo;
2602 	__u32 valid_lft;
2603 	__u32 prefered_lft;
2604 	int addr_type, err;
2605 	u32 addr_flags = 0;
2606 	struct inet6_dev *in6_dev;
2607 	struct net *net = dev_net(dev);
2608 
2609 	pinfo = (struct prefix_info *) opt;
2610 
2611 	if (len < sizeof(struct prefix_info)) {
2612 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2613 		return;
2614 	}
2615 
2616 	/*
2617 	 *	Validation checks ([ADDRCONF], page 19)
2618 	 */
2619 
2620 	addr_type = ipv6_addr_type(&pinfo->prefix);
2621 
2622 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2623 		return;
2624 
2625 	valid_lft = ntohl(pinfo->valid);
2626 	prefered_lft = ntohl(pinfo->prefered);
2627 
2628 	if (prefered_lft > valid_lft) {
2629 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2630 		return;
2631 	}
2632 
2633 	in6_dev = in6_dev_get(dev);
2634 
2635 	if (!in6_dev) {
2636 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2637 				    dev->name);
2638 		return;
2639 	}
2640 
2641 	/*
2642 	 *	Two things going on here:
2643 	 *	1) Add routes for on-link prefixes
2644 	 *	2) Configure prefixes with the auto flag set
2645 	 */
2646 
2647 	if (pinfo->onlink) {
2648 		struct fib6_info *rt;
2649 		unsigned long rt_expires;
2650 
2651 		/* Avoid arithmetic overflow. Really, we could
2652 		 * save rt_expires in seconds, likely valid_lft,
2653 		 * but it would require division in fib gc, that it
2654 		 * not good.
2655 		 */
2656 		if (HZ > USER_HZ)
2657 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2658 		else
2659 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2660 
2661 		if (addrconf_finite_timeout(rt_expires))
2662 			rt_expires *= HZ;
2663 
2664 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2665 					       pinfo->prefix_len,
2666 					       dev,
2667 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2668 					       RTF_GATEWAY | RTF_DEFAULT);
2669 
2670 		if (rt) {
2671 			/* Autoconf prefix route */
2672 			if (valid_lft == 0) {
2673 				ip6_del_rt(net, rt);
2674 				rt = NULL;
2675 			} else if (addrconf_finite_timeout(rt_expires)) {
2676 				/* not infinity */
2677 				fib6_set_expires(rt, jiffies + rt_expires);
2678 			} else {
2679 				fib6_clean_expires(rt);
2680 			}
2681 		} else if (valid_lft) {
2682 			clock_t expires = 0;
2683 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2684 			if (addrconf_finite_timeout(rt_expires)) {
2685 				/* not infinity */
2686 				flags |= RTF_EXPIRES;
2687 				expires = jiffies_to_clock_t(rt_expires);
2688 			}
2689 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2690 					      0, dev, expires, flags,
2691 					      GFP_ATOMIC);
2692 		}
2693 		fib6_info_release(rt);
2694 	}
2695 
2696 	/* Try to figure out our local address for this prefix */
2697 
2698 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2699 		struct in6_addr addr;
2700 		bool tokenized = false, dev_addr_generated = false;
2701 
2702 		if (pinfo->prefix_len == 64) {
2703 			memcpy(&addr, &pinfo->prefix, 8);
2704 
2705 			if (!ipv6_addr_any(&in6_dev->token)) {
2706 				read_lock_bh(&in6_dev->lock);
2707 				memcpy(addr.s6_addr + 8,
2708 				       in6_dev->token.s6_addr + 8, 8);
2709 				read_unlock_bh(&in6_dev->lock);
2710 				tokenized = true;
2711 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2712 				   !ipv6_generate_stable_address(&addr, 0,
2713 								 in6_dev)) {
2714 				addr_flags |= IFA_F_STABLE_PRIVACY;
2715 				goto ok;
2716 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2717 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2718 				goto put;
2719 			} else {
2720 				dev_addr_generated = true;
2721 			}
2722 			goto ok;
2723 		}
2724 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2725 				    pinfo->prefix_len);
2726 		goto put;
2727 
2728 ok:
2729 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2730 						   &addr, addr_type,
2731 						   addr_flags, sllao,
2732 						   tokenized, valid_lft,
2733 						   prefered_lft);
2734 		if (err)
2735 			goto put;
2736 
2737 		/* Ignore error case here because previous prefix add addr was
2738 		 * successful which will be notified.
2739 		 */
2740 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2741 					      addr_type, addr_flags, sllao,
2742 					      tokenized, valid_lft,
2743 					      prefered_lft,
2744 					      dev_addr_generated);
2745 	}
2746 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2747 put:
2748 	in6_dev_put(in6_dev);
2749 }
2750 
2751 /*
2752  *	Set destination address.
2753  *	Special case for SIT interfaces where we create a new "virtual"
2754  *	device.
2755  */
2756 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2757 {
2758 	struct in6_ifreq ireq;
2759 	struct net_device *dev;
2760 	int err = -EINVAL;
2761 
2762 	rtnl_lock();
2763 
2764 	err = -EFAULT;
2765 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2766 		goto err_exit;
2767 
2768 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2769 
2770 	err = -ENODEV;
2771 	if (!dev)
2772 		goto err_exit;
2773 
2774 #if IS_ENABLED(CONFIG_IPV6_SIT)
2775 	if (dev->type == ARPHRD_SIT) {
2776 		const struct net_device_ops *ops = dev->netdev_ops;
2777 		struct ifreq ifr;
2778 		struct ip_tunnel_parm p;
2779 
2780 		err = -EADDRNOTAVAIL;
2781 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2782 			goto err_exit;
2783 
2784 		memset(&p, 0, sizeof(p));
2785 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2786 		p.iph.saddr = 0;
2787 		p.iph.version = 4;
2788 		p.iph.ihl = 5;
2789 		p.iph.protocol = IPPROTO_IPV6;
2790 		p.iph.ttl = 64;
2791 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2792 
2793 		if (ops->ndo_do_ioctl) {
2794 			mm_segment_t oldfs = get_fs();
2795 
2796 			set_fs(KERNEL_DS);
2797 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2798 			set_fs(oldfs);
2799 		} else
2800 			err = -EOPNOTSUPP;
2801 
2802 		if (err == 0) {
2803 			err = -ENOBUFS;
2804 			dev = __dev_get_by_name(net, p.name);
2805 			if (!dev)
2806 				goto err_exit;
2807 			err = dev_open(dev);
2808 		}
2809 	}
2810 #endif
2811 
2812 err_exit:
2813 	rtnl_unlock();
2814 	return err;
2815 }
2816 
2817 static int ipv6_mc_config(struct sock *sk, bool join,
2818 			  const struct in6_addr *addr, int ifindex)
2819 {
2820 	int ret;
2821 
2822 	ASSERT_RTNL();
2823 
2824 	lock_sock(sk);
2825 	if (join)
2826 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2827 	else
2828 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2829 	release_sock(sk);
2830 
2831 	return ret;
2832 }
2833 
2834 /*
2835  *	Manual configuration of address on an interface
2836  */
2837 static int inet6_addr_add(struct net *net, int ifindex,
2838 			  struct ifa6_config *cfg,
2839 			  struct netlink_ext_ack *extack)
2840 {
2841 	struct inet6_ifaddr *ifp;
2842 	struct inet6_dev *idev;
2843 	struct net_device *dev;
2844 	unsigned long timeout;
2845 	clock_t expires;
2846 	u32 flags;
2847 
2848 	ASSERT_RTNL();
2849 
2850 	if (cfg->plen > 128)
2851 		return -EINVAL;
2852 
2853 	/* check the lifetime */
2854 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2855 		return -EINVAL;
2856 
2857 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2858 		return -EINVAL;
2859 
2860 	dev = __dev_get_by_index(net, ifindex);
2861 	if (!dev)
2862 		return -ENODEV;
2863 
2864 	idev = addrconf_add_dev(dev);
2865 	if (IS_ERR(idev))
2866 		return PTR_ERR(idev);
2867 
2868 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2869 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2870 					 true, cfg->pfx, ifindex);
2871 
2872 		if (ret < 0)
2873 			return ret;
2874 	}
2875 
2876 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2877 
2878 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2879 	if (addrconf_finite_timeout(timeout)) {
2880 		expires = jiffies_to_clock_t(timeout * HZ);
2881 		cfg->valid_lft = timeout;
2882 		flags = RTF_EXPIRES;
2883 	} else {
2884 		expires = 0;
2885 		flags = 0;
2886 		cfg->ifa_flags |= IFA_F_PERMANENT;
2887 	}
2888 
2889 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2890 	if (addrconf_finite_timeout(timeout)) {
2891 		if (timeout == 0)
2892 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2893 		cfg->preferred_lft = timeout;
2894 	}
2895 
2896 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2897 	if (!IS_ERR(ifp)) {
2898 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2899 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2900 					      ifp->rt_priority, dev, expires,
2901 					      flags, GFP_KERNEL);
2902 		}
2903 
2904 		/* Send a netlink notification if DAD is enabled and
2905 		 * optimistic flag is not set
2906 		 */
2907 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2908 			ipv6_ifa_notify(0, ifp);
2909 		/*
2910 		 * Note that section 3.1 of RFC 4429 indicates
2911 		 * that the Optimistic flag should not be set for
2912 		 * manually configured addresses
2913 		 */
2914 		addrconf_dad_start(ifp);
2915 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2916 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2917 					 cfg->preferred_lft, true, jiffies);
2918 		in6_ifa_put(ifp);
2919 		addrconf_verify_rtnl();
2920 		return 0;
2921 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2922 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2923 			       cfg->pfx, ifindex);
2924 	}
2925 
2926 	return PTR_ERR(ifp);
2927 }
2928 
2929 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2930 			  const struct in6_addr *pfx, unsigned int plen)
2931 {
2932 	struct inet6_ifaddr *ifp;
2933 	struct inet6_dev *idev;
2934 	struct net_device *dev;
2935 
2936 	if (plen > 128)
2937 		return -EINVAL;
2938 
2939 	dev = __dev_get_by_index(net, ifindex);
2940 	if (!dev)
2941 		return -ENODEV;
2942 
2943 	idev = __in6_dev_get(dev);
2944 	if (!idev)
2945 		return -ENXIO;
2946 
2947 	read_lock_bh(&idev->lock);
2948 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2949 		if (ifp->prefix_len == plen &&
2950 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2951 			in6_ifa_hold(ifp);
2952 			read_unlock_bh(&idev->lock);
2953 
2954 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2955 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2956 				manage_tempaddrs(idev, ifp, 0, 0, false,
2957 						 jiffies);
2958 			ipv6_del_addr(ifp);
2959 			addrconf_verify_rtnl();
2960 			if (ipv6_addr_is_multicast(pfx)) {
2961 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2962 					       false, pfx, dev->ifindex);
2963 			}
2964 			return 0;
2965 		}
2966 	}
2967 	read_unlock_bh(&idev->lock);
2968 	return -EADDRNOTAVAIL;
2969 }
2970 
2971 
2972 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2973 {
2974 	struct ifa6_config cfg = {
2975 		.ifa_flags = IFA_F_PERMANENT,
2976 		.preferred_lft = INFINITY_LIFE_TIME,
2977 		.valid_lft = INFINITY_LIFE_TIME,
2978 	};
2979 	struct in6_ifreq ireq;
2980 	int err;
2981 
2982 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2983 		return -EPERM;
2984 
2985 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2986 		return -EFAULT;
2987 
2988 	cfg.pfx = &ireq.ifr6_addr;
2989 	cfg.plen = ireq.ifr6_prefixlen;
2990 
2991 	rtnl_lock();
2992 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
2993 	rtnl_unlock();
2994 	return err;
2995 }
2996 
2997 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2998 {
2999 	struct in6_ifreq ireq;
3000 	int err;
3001 
3002 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3003 		return -EPERM;
3004 
3005 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3006 		return -EFAULT;
3007 
3008 	rtnl_lock();
3009 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3010 			     ireq.ifr6_prefixlen);
3011 	rtnl_unlock();
3012 	return err;
3013 }
3014 
3015 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3016 		     int plen, int scope)
3017 {
3018 	struct inet6_ifaddr *ifp;
3019 	struct ifa6_config cfg = {
3020 		.pfx = addr,
3021 		.plen = plen,
3022 		.ifa_flags = IFA_F_PERMANENT,
3023 		.valid_lft = INFINITY_LIFE_TIME,
3024 		.preferred_lft = INFINITY_LIFE_TIME,
3025 		.scope = scope
3026 	};
3027 
3028 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3029 	if (!IS_ERR(ifp)) {
3030 		spin_lock_bh(&ifp->lock);
3031 		ifp->flags &= ~IFA_F_TENTATIVE;
3032 		spin_unlock_bh(&ifp->lock);
3033 		rt_genid_bump_ipv6(dev_net(idev->dev));
3034 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3035 		in6_ifa_put(ifp);
3036 	}
3037 }
3038 
3039 #if IS_ENABLED(CONFIG_IPV6_SIT)
3040 static void sit_add_v4_addrs(struct inet6_dev *idev)
3041 {
3042 	struct in6_addr addr;
3043 	struct net_device *dev;
3044 	struct net *net = dev_net(idev->dev);
3045 	int scope, plen;
3046 	u32 pflags = 0;
3047 
3048 	ASSERT_RTNL();
3049 
3050 	memset(&addr, 0, sizeof(struct in6_addr));
3051 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3052 
3053 	if (idev->dev->flags&IFF_POINTOPOINT) {
3054 		addr.s6_addr32[0] = htonl(0xfe800000);
3055 		scope = IFA_LINK;
3056 		plen = 64;
3057 	} else {
3058 		scope = IPV6_ADDR_COMPATv4;
3059 		plen = 96;
3060 		pflags |= RTF_NONEXTHOP;
3061 	}
3062 
3063 	if (addr.s6_addr32[3]) {
3064 		add_addr(idev, &addr, plen, scope);
3065 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3066 				      GFP_KERNEL);
3067 		return;
3068 	}
3069 
3070 	for_each_netdev(net, dev) {
3071 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3072 		if (in_dev && (dev->flags & IFF_UP)) {
3073 			struct in_ifaddr *ifa;
3074 
3075 			int flag = scope;
3076 
3077 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3078 
3079 				addr.s6_addr32[3] = ifa->ifa_local;
3080 
3081 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3082 					continue;
3083 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3084 					if (idev->dev->flags&IFF_POINTOPOINT)
3085 						continue;
3086 					flag |= IFA_HOST;
3087 				}
3088 
3089 				add_addr(idev, &addr, plen, flag);
3090 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3091 						      0, pflags, GFP_KERNEL);
3092 			}
3093 		}
3094 	}
3095 }
3096 #endif
3097 
3098 static void init_loopback(struct net_device *dev)
3099 {
3100 	struct inet6_dev  *idev;
3101 
3102 	/* ::1 */
3103 
3104 	ASSERT_RTNL();
3105 
3106 	idev = ipv6_find_idev(dev);
3107 	if (!idev) {
3108 		pr_debug("%s: add_dev failed\n", __func__);
3109 		return;
3110 	}
3111 
3112 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3113 }
3114 
3115 void addrconf_add_linklocal(struct inet6_dev *idev,
3116 			    const struct in6_addr *addr, u32 flags)
3117 {
3118 	struct ifa6_config cfg = {
3119 		.pfx = addr,
3120 		.plen = 64,
3121 		.ifa_flags = flags | IFA_F_PERMANENT,
3122 		.valid_lft = INFINITY_LIFE_TIME,
3123 		.preferred_lft = INFINITY_LIFE_TIME,
3124 		.scope = IFA_LINK
3125 	};
3126 	struct inet6_ifaddr *ifp;
3127 
3128 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3129 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3130 	     idev->cnf.optimistic_dad) &&
3131 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3132 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3133 #endif
3134 
3135 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3136 	if (!IS_ERR(ifp)) {
3137 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3138 				      0, 0, GFP_ATOMIC);
3139 		addrconf_dad_start(ifp);
3140 		in6_ifa_put(ifp);
3141 	}
3142 }
3143 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3144 
3145 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3146 {
3147 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3148 		return true;
3149 
3150 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3151 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3152 		return true;
3153 
3154 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3155 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3156 		return true;
3157 
3158 	return false;
3159 }
3160 
3161 static int ipv6_generate_stable_address(struct in6_addr *address,
3162 					u8 dad_count,
3163 					const struct inet6_dev *idev)
3164 {
3165 	static DEFINE_SPINLOCK(lock);
3166 	static __u32 digest[SHA_DIGEST_WORDS];
3167 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3168 
3169 	static union {
3170 		char __data[SHA_MESSAGE_BYTES];
3171 		struct {
3172 			struct in6_addr secret;
3173 			__be32 prefix[2];
3174 			unsigned char hwaddr[MAX_ADDR_LEN];
3175 			u8 dad_count;
3176 		} __packed;
3177 	} data;
3178 
3179 	struct in6_addr secret;
3180 	struct in6_addr temp;
3181 	struct net *net = dev_net(idev->dev);
3182 
3183 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3184 
3185 	if (idev->cnf.stable_secret.initialized)
3186 		secret = idev->cnf.stable_secret.secret;
3187 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3188 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3189 	else
3190 		return -1;
3191 
3192 retry:
3193 	spin_lock_bh(&lock);
3194 
3195 	sha_init(digest);
3196 	memset(&data, 0, sizeof(data));
3197 	memset(workspace, 0, sizeof(workspace));
3198 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3199 	data.prefix[0] = address->s6_addr32[0];
3200 	data.prefix[1] = address->s6_addr32[1];
3201 	data.secret = secret;
3202 	data.dad_count = dad_count;
3203 
3204 	sha_transform(digest, data.__data, workspace);
3205 
3206 	temp = *address;
3207 	temp.s6_addr32[2] = (__force __be32)digest[0];
3208 	temp.s6_addr32[3] = (__force __be32)digest[1];
3209 
3210 	spin_unlock_bh(&lock);
3211 
3212 	if (ipv6_reserved_interfaceid(temp)) {
3213 		dad_count++;
3214 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3215 			return -1;
3216 		goto retry;
3217 	}
3218 
3219 	*address = temp;
3220 	return 0;
3221 }
3222 
3223 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3224 {
3225 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3226 
3227 	if (s->initialized)
3228 		return;
3229 	s = &idev->cnf.stable_secret;
3230 	get_random_bytes(&s->secret, sizeof(s->secret));
3231 	s->initialized = true;
3232 }
3233 
3234 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3235 {
3236 	struct in6_addr addr;
3237 
3238 	/* no link local addresses on L3 master devices */
3239 	if (netif_is_l3_master(idev->dev))
3240 		return;
3241 
3242 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3243 
3244 	switch (idev->cnf.addr_gen_mode) {
3245 	case IN6_ADDR_GEN_MODE_RANDOM:
3246 		ipv6_gen_mode_random_init(idev);
3247 		/* fallthrough */
3248 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3249 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3250 			addrconf_add_linklocal(idev, &addr,
3251 					       IFA_F_STABLE_PRIVACY);
3252 		else if (prefix_route)
3253 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3254 					      0, 0, GFP_KERNEL);
3255 		break;
3256 	case IN6_ADDR_GEN_MODE_EUI64:
3257 		/* addrconf_add_linklocal also adds a prefix_route and we
3258 		 * only need to care about prefix routes if ipv6_generate_eui64
3259 		 * couldn't generate one.
3260 		 */
3261 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3262 			addrconf_add_linklocal(idev, &addr, 0);
3263 		else if (prefix_route)
3264 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3265 					      0, 0, GFP_KERNEL);
3266 		break;
3267 	case IN6_ADDR_GEN_MODE_NONE:
3268 	default:
3269 		/* will not add any link local address */
3270 		break;
3271 	}
3272 }
3273 
3274 static void addrconf_dev_config(struct net_device *dev)
3275 {
3276 	struct inet6_dev *idev;
3277 
3278 	ASSERT_RTNL();
3279 
3280 	if ((dev->type != ARPHRD_ETHER) &&
3281 	    (dev->type != ARPHRD_FDDI) &&
3282 	    (dev->type != ARPHRD_ARCNET) &&
3283 	    (dev->type != ARPHRD_INFINIBAND) &&
3284 	    (dev->type != ARPHRD_IEEE1394) &&
3285 	    (dev->type != ARPHRD_TUNNEL6) &&
3286 	    (dev->type != ARPHRD_6LOWPAN) &&
3287 	    (dev->type != ARPHRD_IP6GRE) &&
3288 	    (dev->type != ARPHRD_IPGRE) &&
3289 	    (dev->type != ARPHRD_TUNNEL) &&
3290 	    (dev->type != ARPHRD_NONE) &&
3291 	    (dev->type != ARPHRD_RAWIP)) {
3292 		/* Alas, we support only Ethernet autoconfiguration. */
3293 		return;
3294 	}
3295 
3296 	idev = addrconf_add_dev(dev);
3297 	if (IS_ERR(idev))
3298 		return;
3299 
3300 	/* this device type has no EUI support */
3301 	if (dev->type == ARPHRD_NONE &&
3302 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3303 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3304 
3305 	addrconf_addr_gen(idev, false);
3306 }
3307 
3308 #if IS_ENABLED(CONFIG_IPV6_SIT)
3309 static void addrconf_sit_config(struct net_device *dev)
3310 {
3311 	struct inet6_dev *idev;
3312 
3313 	ASSERT_RTNL();
3314 
3315 	/*
3316 	 * Configure the tunnel with one of our IPv4
3317 	 * addresses... we should configure all of
3318 	 * our v4 addrs in the tunnel
3319 	 */
3320 
3321 	idev = ipv6_find_idev(dev);
3322 	if (!idev) {
3323 		pr_debug("%s: add_dev failed\n", __func__);
3324 		return;
3325 	}
3326 
3327 	if (dev->priv_flags & IFF_ISATAP) {
3328 		addrconf_addr_gen(idev, false);
3329 		return;
3330 	}
3331 
3332 	sit_add_v4_addrs(idev);
3333 
3334 	if (dev->flags&IFF_POINTOPOINT)
3335 		addrconf_add_mroute(dev);
3336 }
3337 #endif
3338 
3339 #if IS_ENABLED(CONFIG_NET_IPGRE)
3340 static void addrconf_gre_config(struct net_device *dev)
3341 {
3342 	struct inet6_dev *idev;
3343 
3344 	ASSERT_RTNL();
3345 
3346 	idev = ipv6_find_idev(dev);
3347 	if (!idev) {
3348 		pr_debug("%s: add_dev failed\n", __func__);
3349 		return;
3350 	}
3351 
3352 	addrconf_addr_gen(idev, true);
3353 	if (dev->flags & IFF_POINTOPOINT)
3354 		addrconf_add_mroute(dev);
3355 }
3356 #endif
3357 
3358 static int fixup_permanent_addr(struct net *net,
3359 				struct inet6_dev *idev,
3360 				struct inet6_ifaddr *ifp)
3361 {
3362 	/* !fib6_node means the host route was removed from the
3363 	 * FIB, for example, if 'lo' device is taken down. In that
3364 	 * case regenerate the host route.
3365 	 */
3366 	if (!ifp->rt || !ifp->rt->fib6_node) {
3367 		struct fib6_info *f6i, *prev;
3368 
3369 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3370 					 GFP_ATOMIC);
3371 		if (IS_ERR(f6i))
3372 			return PTR_ERR(f6i);
3373 
3374 		/* ifp->rt can be accessed outside of rtnl */
3375 		spin_lock(&ifp->lock);
3376 		prev = ifp->rt;
3377 		ifp->rt = f6i;
3378 		spin_unlock(&ifp->lock);
3379 
3380 		fib6_info_release(prev);
3381 	}
3382 
3383 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3384 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3385 				      ifp->rt_priority, idev->dev, 0, 0,
3386 				      GFP_ATOMIC);
3387 	}
3388 
3389 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3390 		addrconf_dad_start(ifp);
3391 
3392 	return 0;
3393 }
3394 
3395 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3396 {
3397 	struct inet6_ifaddr *ifp, *tmp;
3398 	struct inet6_dev *idev;
3399 
3400 	idev = __in6_dev_get(dev);
3401 	if (!idev)
3402 		return;
3403 
3404 	write_lock_bh(&idev->lock);
3405 
3406 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3407 		if ((ifp->flags & IFA_F_PERMANENT) &&
3408 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3409 			write_unlock_bh(&idev->lock);
3410 			in6_ifa_hold(ifp);
3411 			ipv6_del_addr(ifp);
3412 			write_lock_bh(&idev->lock);
3413 
3414 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3415 					     idev->dev->name, &ifp->addr);
3416 		}
3417 	}
3418 
3419 	write_unlock_bh(&idev->lock);
3420 }
3421 
3422 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3423 			   void *ptr)
3424 {
3425 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3426 	struct netdev_notifier_changeupper_info *info;
3427 	struct inet6_dev *idev = __in6_dev_get(dev);
3428 	struct net *net = dev_net(dev);
3429 	int run_pending = 0;
3430 	int err;
3431 
3432 	switch (event) {
3433 	case NETDEV_REGISTER:
3434 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3435 			idev = ipv6_add_dev(dev);
3436 			if (IS_ERR(idev))
3437 				return notifier_from_errno(PTR_ERR(idev));
3438 		}
3439 		break;
3440 
3441 	case NETDEV_CHANGEMTU:
3442 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3443 		if (dev->mtu < IPV6_MIN_MTU) {
3444 			addrconf_ifdown(dev, dev != net->loopback_dev);
3445 			break;
3446 		}
3447 
3448 		if (idev) {
3449 			rt6_mtu_change(dev, dev->mtu);
3450 			idev->cnf.mtu6 = dev->mtu;
3451 			break;
3452 		}
3453 
3454 		/* allocate new idev */
3455 		idev = ipv6_add_dev(dev);
3456 		if (IS_ERR(idev))
3457 			break;
3458 
3459 		/* device is still not ready */
3460 		if (!(idev->if_flags & IF_READY))
3461 			break;
3462 
3463 		run_pending = 1;
3464 
3465 		/* fall through */
3466 
3467 	case NETDEV_UP:
3468 	case NETDEV_CHANGE:
3469 		if (dev->flags & IFF_SLAVE)
3470 			break;
3471 
3472 		if (idev && idev->cnf.disable_ipv6)
3473 			break;
3474 
3475 		if (event == NETDEV_UP) {
3476 			/* restore routes for permanent addresses */
3477 			addrconf_permanent_addr(net, dev);
3478 
3479 			if (!addrconf_link_ready(dev)) {
3480 				/* device is not ready yet. */
3481 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3482 					dev->name);
3483 				break;
3484 			}
3485 
3486 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3487 				idev = ipv6_add_dev(dev);
3488 
3489 			if (!IS_ERR_OR_NULL(idev)) {
3490 				idev->if_flags |= IF_READY;
3491 				run_pending = 1;
3492 			}
3493 		} else if (event == NETDEV_CHANGE) {
3494 			if (!addrconf_link_ready(dev)) {
3495 				/* device is still not ready. */
3496 				rt6_sync_down_dev(dev, event);
3497 				break;
3498 			}
3499 
3500 			if (idev) {
3501 				if (idev->if_flags & IF_READY) {
3502 					/* device is already configured -
3503 					 * but resend MLD reports, we might
3504 					 * have roamed and need to update
3505 					 * multicast snooping switches
3506 					 */
3507 					ipv6_mc_up(idev);
3508 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3509 					break;
3510 				}
3511 				idev->if_flags |= IF_READY;
3512 			}
3513 
3514 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3515 				dev->name);
3516 
3517 			run_pending = 1;
3518 		}
3519 
3520 		switch (dev->type) {
3521 #if IS_ENABLED(CONFIG_IPV6_SIT)
3522 		case ARPHRD_SIT:
3523 			addrconf_sit_config(dev);
3524 			break;
3525 #endif
3526 #if IS_ENABLED(CONFIG_NET_IPGRE)
3527 		case ARPHRD_IPGRE:
3528 			addrconf_gre_config(dev);
3529 			break;
3530 #endif
3531 		case ARPHRD_LOOPBACK:
3532 			init_loopback(dev);
3533 			break;
3534 
3535 		default:
3536 			addrconf_dev_config(dev);
3537 			break;
3538 		}
3539 
3540 		if (!IS_ERR_OR_NULL(idev)) {
3541 			if (run_pending)
3542 				addrconf_dad_run(idev);
3543 
3544 			/* Device has an address by now */
3545 			rt6_sync_up(dev, RTNH_F_DEAD);
3546 
3547 			/*
3548 			 * If the MTU changed during the interface down,
3549 			 * when the interface up, the changed MTU must be
3550 			 * reflected in the idev as well as routers.
3551 			 */
3552 			if (idev->cnf.mtu6 != dev->mtu &&
3553 			    dev->mtu >= IPV6_MIN_MTU) {
3554 				rt6_mtu_change(dev, dev->mtu);
3555 				idev->cnf.mtu6 = dev->mtu;
3556 			}
3557 			idev->tstamp = jiffies;
3558 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3559 
3560 			/*
3561 			 * If the changed mtu during down is lower than
3562 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3563 			 */
3564 			if (dev->mtu < IPV6_MIN_MTU)
3565 				addrconf_ifdown(dev, dev != net->loopback_dev);
3566 		}
3567 		break;
3568 
3569 	case NETDEV_DOWN:
3570 	case NETDEV_UNREGISTER:
3571 		/*
3572 		 *	Remove all addresses from this interface.
3573 		 */
3574 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3575 		break;
3576 
3577 	case NETDEV_CHANGENAME:
3578 		if (idev) {
3579 			snmp6_unregister_dev(idev);
3580 			addrconf_sysctl_unregister(idev);
3581 			err = addrconf_sysctl_register(idev);
3582 			if (err)
3583 				return notifier_from_errno(err);
3584 			err = snmp6_register_dev(idev);
3585 			if (err) {
3586 				addrconf_sysctl_unregister(idev);
3587 				return notifier_from_errno(err);
3588 			}
3589 		}
3590 		break;
3591 
3592 	case NETDEV_PRE_TYPE_CHANGE:
3593 	case NETDEV_POST_TYPE_CHANGE:
3594 		if (idev)
3595 			addrconf_type_change(dev, event);
3596 		break;
3597 
3598 	case NETDEV_CHANGEUPPER:
3599 		info = ptr;
3600 
3601 		/* flush all routes if dev is linked to or unlinked from
3602 		 * an L3 master device (e.g., VRF)
3603 		 */
3604 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3605 			addrconf_ifdown(dev, 0);
3606 	}
3607 
3608 	return NOTIFY_OK;
3609 }
3610 
3611 /*
3612  *	addrconf module should be notified of a device going up
3613  */
3614 static struct notifier_block ipv6_dev_notf = {
3615 	.notifier_call = addrconf_notify,
3616 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3617 };
3618 
3619 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3620 {
3621 	struct inet6_dev *idev;
3622 	ASSERT_RTNL();
3623 
3624 	idev = __in6_dev_get(dev);
3625 
3626 	if (event == NETDEV_POST_TYPE_CHANGE)
3627 		ipv6_mc_remap(idev);
3628 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3629 		ipv6_mc_unmap(idev);
3630 }
3631 
3632 static bool addr_is_local(const struct in6_addr *addr)
3633 {
3634 	return ipv6_addr_type(addr) &
3635 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3636 }
3637 
3638 static int addrconf_ifdown(struct net_device *dev, int how)
3639 {
3640 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3641 	struct net *net = dev_net(dev);
3642 	struct inet6_dev *idev;
3643 	struct inet6_ifaddr *ifa, *tmp;
3644 	bool keep_addr = false;
3645 	int state, i;
3646 
3647 	ASSERT_RTNL();
3648 
3649 	rt6_disable_ip(dev, event);
3650 
3651 	idev = __in6_dev_get(dev);
3652 	if (!idev)
3653 		return -ENODEV;
3654 
3655 	/*
3656 	 * Step 1: remove reference to ipv6 device from parent device.
3657 	 *	   Do not dev_put!
3658 	 */
3659 	if (how) {
3660 		idev->dead = 1;
3661 
3662 		/* protected by rtnl_lock */
3663 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3664 
3665 		/* Step 1.5: remove snmp6 entry */
3666 		snmp6_unregister_dev(idev);
3667 
3668 	}
3669 
3670 	/* combine the user config with event to determine if permanent
3671 	 * addresses are to be removed from address hash table
3672 	 */
3673 	if (!how && !idev->cnf.disable_ipv6) {
3674 		/* aggregate the system setting and interface setting */
3675 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3676 
3677 		if (!_keep_addr)
3678 			_keep_addr = idev->cnf.keep_addr_on_down;
3679 
3680 		keep_addr = (_keep_addr > 0);
3681 	}
3682 
3683 	/* Step 2: clear hash table */
3684 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3685 		struct hlist_head *h = &inet6_addr_lst[i];
3686 
3687 		spin_lock_bh(&addrconf_hash_lock);
3688 restart:
3689 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3690 			if (ifa->idev == idev) {
3691 				addrconf_del_dad_work(ifa);
3692 				/* combined flag + permanent flag decide if
3693 				 * address is retained on a down event
3694 				 */
3695 				if (!keep_addr ||
3696 				    !(ifa->flags & IFA_F_PERMANENT) ||
3697 				    addr_is_local(&ifa->addr)) {
3698 					hlist_del_init_rcu(&ifa->addr_lst);
3699 					goto restart;
3700 				}
3701 			}
3702 		}
3703 		spin_unlock_bh(&addrconf_hash_lock);
3704 	}
3705 
3706 	write_lock_bh(&idev->lock);
3707 
3708 	addrconf_del_rs_timer(idev);
3709 
3710 	/* Step 2: clear flags for stateless addrconf */
3711 	if (!how)
3712 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3713 
3714 	/* Step 3: clear tempaddr list */
3715 	while (!list_empty(&idev->tempaddr_list)) {
3716 		ifa = list_first_entry(&idev->tempaddr_list,
3717 				       struct inet6_ifaddr, tmp_list);
3718 		list_del(&ifa->tmp_list);
3719 		write_unlock_bh(&idev->lock);
3720 		spin_lock_bh(&ifa->lock);
3721 
3722 		if (ifa->ifpub) {
3723 			in6_ifa_put(ifa->ifpub);
3724 			ifa->ifpub = NULL;
3725 		}
3726 		spin_unlock_bh(&ifa->lock);
3727 		in6_ifa_put(ifa);
3728 		write_lock_bh(&idev->lock);
3729 	}
3730 
3731 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3732 		struct fib6_info *rt = NULL;
3733 		bool keep;
3734 
3735 		addrconf_del_dad_work(ifa);
3736 
3737 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3738 			!addr_is_local(&ifa->addr);
3739 
3740 		write_unlock_bh(&idev->lock);
3741 		spin_lock_bh(&ifa->lock);
3742 
3743 		if (keep) {
3744 			/* set state to skip the notifier below */
3745 			state = INET6_IFADDR_STATE_DEAD;
3746 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3747 			if (!(ifa->flags & IFA_F_NODAD))
3748 				ifa->flags |= IFA_F_TENTATIVE;
3749 
3750 			rt = ifa->rt;
3751 			ifa->rt = NULL;
3752 		} else {
3753 			state = ifa->state;
3754 			ifa->state = INET6_IFADDR_STATE_DEAD;
3755 		}
3756 
3757 		spin_unlock_bh(&ifa->lock);
3758 
3759 		if (rt)
3760 			ip6_del_rt(net, rt);
3761 
3762 		if (state != INET6_IFADDR_STATE_DEAD) {
3763 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3764 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3765 		} else {
3766 			if (idev->cnf.forwarding)
3767 				addrconf_leave_anycast(ifa);
3768 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3769 		}
3770 
3771 		write_lock_bh(&idev->lock);
3772 		if (!keep) {
3773 			list_del_rcu(&ifa->if_list);
3774 			in6_ifa_put(ifa);
3775 		}
3776 	}
3777 
3778 	write_unlock_bh(&idev->lock);
3779 
3780 	/* Step 5: Discard anycast and multicast list */
3781 	if (how) {
3782 		ipv6_ac_destroy_dev(idev);
3783 		ipv6_mc_destroy_dev(idev);
3784 	} else {
3785 		ipv6_mc_down(idev);
3786 	}
3787 
3788 	idev->tstamp = jiffies;
3789 
3790 	/* Last: Shot the device (if unregistered) */
3791 	if (how) {
3792 		addrconf_sysctl_unregister(idev);
3793 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3794 		neigh_ifdown(&nd_tbl, dev);
3795 		in6_dev_put(idev);
3796 	}
3797 	return 0;
3798 }
3799 
3800 static void addrconf_rs_timer(struct timer_list *t)
3801 {
3802 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3803 	struct net_device *dev = idev->dev;
3804 	struct in6_addr lladdr;
3805 
3806 	write_lock(&idev->lock);
3807 	if (idev->dead || !(idev->if_flags & IF_READY))
3808 		goto out;
3809 
3810 	if (!ipv6_accept_ra(idev))
3811 		goto out;
3812 
3813 	/* Announcement received after solicitation was sent */
3814 	if (idev->if_flags & IF_RA_RCVD)
3815 		goto out;
3816 
3817 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3818 		write_unlock(&idev->lock);
3819 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3820 			ndisc_send_rs(dev, &lladdr,
3821 				      &in6addr_linklocal_allrouters);
3822 		else
3823 			goto put;
3824 
3825 		write_lock(&idev->lock);
3826 		idev->rs_interval = rfc3315_s14_backoff_update(
3827 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3828 		/* The wait after the last probe can be shorter */
3829 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3830 					     idev->cnf.rtr_solicits) ?
3831 				      idev->cnf.rtr_solicit_delay :
3832 				      idev->rs_interval);
3833 	} else {
3834 		/*
3835 		 * Note: we do not support deprecated "all on-link"
3836 		 * assumption any longer.
3837 		 */
3838 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3839 	}
3840 
3841 out:
3842 	write_unlock(&idev->lock);
3843 put:
3844 	in6_dev_put(idev);
3845 }
3846 
3847 /*
3848  *	Duplicate Address Detection
3849  */
3850 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3851 {
3852 	unsigned long rand_num;
3853 	struct inet6_dev *idev = ifp->idev;
3854 	u64 nonce;
3855 
3856 	if (ifp->flags & IFA_F_OPTIMISTIC)
3857 		rand_num = 0;
3858 	else
3859 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3860 
3861 	nonce = 0;
3862 	if (idev->cnf.enhanced_dad ||
3863 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3864 		do
3865 			get_random_bytes(&nonce, 6);
3866 		while (nonce == 0);
3867 	}
3868 	ifp->dad_nonce = nonce;
3869 	ifp->dad_probes = idev->cnf.dad_transmits;
3870 	addrconf_mod_dad_work(ifp, rand_num);
3871 }
3872 
3873 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3874 {
3875 	struct inet6_dev *idev = ifp->idev;
3876 	struct net_device *dev = idev->dev;
3877 	bool bump_id, notify = false;
3878 	struct net *net;
3879 
3880 	addrconf_join_solict(dev, &ifp->addr);
3881 
3882 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3883 
3884 	read_lock_bh(&idev->lock);
3885 	spin_lock(&ifp->lock);
3886 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3887 		goto out;
3888 
3889 	net = dev_net(dev);
3890 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3891 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3892 	     idev->cnf.accept_dad < 1) ||
3893 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3894 	    ifp->flags & IFA_F_NODAD) {
3895 		bool send_na = false;
3896 
3897 		if (ifp->flags & IFA_F_TENTATIVE &&
3898 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3899 			send_na = true;
3900 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3901 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3902 		spin_unlock(&ifp->lock);
3903 		read_unlock_bh(&idev->lock);
3904 
3905 		addrconf_dad_completed(ifp, bump_id, send_na);
3906 		return;
3907 	}
3908 
3909 	if (!(idev->if_flags & IF_READY)) {
3910 		spin_unlock(&ifp->lock);
3911 		read_unlock_bh(&idev->lock);
3912 		/*
3913 		 * If the device is not ready:
3914 		 * - keep it tentative if it is a permanent address.
3915 		 * - otherwise, kill it.
3916 		 */
3917 		in6_ifa_hold(ifp);
3918 		addrconf_dad_stop(ifp, 0);
3919 		return;
3920 	}
3921 
3922 	/*
3923 	 * Optimistic nodes can start receiving
3924 	 * Frames right away
3925 	 */
3926 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3927 		ip6_ins_rt(net, ifp->rt);
3928 		if (ipv6_use_optimistic_addr(net, idev)) {
3929 			/* Because optimistic nodes can use this address,
3930 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3931 			 */
3932 			notify = true;
3933 		}
3934 	}
3935 
3936 	addrconf_dad_kick(ifp);
3937 out:
3938 	spin_unlock(&ifp->lock);
3939 	read_unlock_bh(&idev->lock);
3940 	if (notify)
3941 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3942 }
3943 
3944 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3945 {
3946 	bool begin_dad = false;
3947 
3948 	spin_lock_bh(&ifp->lock);
3949 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3950 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3951 		begin_dad = true;
3952 	}
3953 	spin_unlock_bh(&ifp->lock);
3954 
3955 	if (begin_dad)
3956 		addrconf_mod_dad_work(ifp, 0);
3957 }
3958 
3959 static void addrconf_dad_work(struct work_struct *w)
3960 {
3961 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3962 						struct inet6_ifaddr,
3963 						dad_work);
3964 	struct inet6_dev *idev = ifp->idev;
3965 	bool bump_id, disable_ipv6 = false;
3966 	struct in6_addr mcaddr;
3967 
3968 	enum {
3969 		DAD_PROCESS,
3970 		DAD_BEGIN,
3971 		DAD_ABORT,
3972 	} action = DAD_PROCESS;
3973 
3974 	rtnl_lock();
3975 
3976 	spin_lock_bh(&ifp->lock);
3977 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3978 		action = DAD_BEGIN;
3979 		ifp->state = INET6_IFADDR_STATE_DAD;
3980 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3981 		action = DAD_ABORT;
3982 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3983 
3984 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3985 		     idev->cnf.accept_dad > 1) &&
3986 		    !idev->cnf.disable_ipv6 &&
3987 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3988 			struct in6_addr addr;
3989 
3990 			addr.s6_addr32[0] = htonl(0xfe800000);
3991 			addr.s6_addr32[1] = 0;
3992 
3993 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3994 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3995 				/* DAD failed for link-local based on MAC */
3996 				idev->cnf.disable_ipv6 = 1;
3997 
3998 				pr_info("%s: IPv6 being disabled!\n",
3999 					ifp->idev->dev->name);
4000 				disable_ipv6 = true;
4001 			}
4002 		}
4003 	}
4004 	spin_unlock_bh(&ifp->lock);
4005 
4006 	if (action == DAD_BEGIN) {
4007 		addrconf_dad_begin(ifp);
4008 		goto out;
4009 	} else if (action == DAD_ABORT) {
4010 		in6_ifa_hold(ifp);
4011 		addrconf_dad_stop(ifp, 1);
4012 		if (disable_ipv6)
4013 			addrconf_ifdown(idev->dev, 0);
4014 		goto out;
4015 	}
4016 
4017 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4018 		goto out;
4019 
4020 	write_lock_bh(&idev->lock);
4021 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4022 		write_unlock_bh(&idev->lock);
4023 		goto out;
4024 	}
4025 
4026 	spin_lock(&ifp->lock);
4027 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4028 		spin_unlock(&ifp->lock);
4029 		write_unlock_bh(&idev->lock);
4030 		goto out;
4031 	}
4032 
4033 	if (ifp->dad_probes == 0) {
4034 		bool send_na = false;
4035 
4036 		/*
4037 		 * DAD was successful
4038 		 */
4039 
4040 		if (ifp->flags & IFA_F_TENTATIVE &&
4041 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4042 			send_na = true;
4043 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4044 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4045 		spin_unlock(&ifp->lock);
4046 		write_unlock_bh(&idev->lock);
4047 
4048 		addrconf_dad_completed(ifp, bump_id, send_na);
4049 
4050 		goto out;
4051 	}
4052 
4053 	ifp->dad_probes--;
4054 	addrconf_mod_dad_work(ifp,
4055 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4056 	spin_unlock(&ifp->lock);
4057 	write_unlock_bh(&idev->lock);
4058 
4059 	/* send a neighbour solicitation for our addr */
4060 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4061 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4062 		      ifp->dad_nonce);
4063 out:
4064 	in6_ifa_put(ifp);
4065 	rtnl_unlock();
4066 }
4067 
4068 /* ifp->idev must be at least read locked */
4069 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4070 {
4071 	struct inet6_ifaddr *ifpiter;
4072 	struct inet6_dev *idev = ifp->idev;
4073 
4074 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4075 		if (ifpiter->scope > IFA_LINK)
4076 			break;
4077 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4078 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4079 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4080 		    IFA_F_PERMANENT)
4081 			return false;
4082 	}
4083 	return true;
4084 }
4085 
4086 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4087 				   bool send_na)
4088 {
4089 	struct net_device *dev = ifp->idev->dev;
4090 	struct in6_addr lladdr;
4091 	bool send_rs, send_mld;
4092 
4093 	addrconf_del_dad_work(ifp);
4094 
4095 	/*
4096 	 *	Configure the address for reception. Now it is valid.
4097 	 */
4098 
4099 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4100 
4101 	/* If added prefix is link local and we are prepared to process
4102 	   router advertisements, start sending router solicitations.
4103 	 */
4104 
4105 	read_lock_bh(&ifp->idev->lock);
4106 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4107 	send_rs = send_mld &&
4108 		  ipv6_accept_ra(ifp->idev) &&
4109 		  ifp->idev->cnf.rtr_solicits != 0 &&
4110 		  (dev->flags&IFF_LOOPBACK) == 0;
4111 	read_unlock_bh(&ifp->idev->lock);
4112 
4113 	/* While dad is in progress mld report's source address is in6_addrany.
4114 	 * Resend with proper ll now.
4115 	 */
4116 	if (send_mld)
4117 		ipv6_mc_dad_complete(ifp->idev);
4118 
4119 	/* send unsolicited NA if enabled */
4120 	if (send_na &&
4121 	    (ifp->idev->cnf.ndisc_notify ||
4122 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4123 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4124 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4125 			      /*solicited=*/ false, /*override=*/ true,
4126 			      /*inc_opt=*/ true);
4127 	}
4128 
4129 	if (send_rs) {
4130 		/*
4131 		 *	If a host as already performed a random delay
4132 		 *	[...] as part of DAD [...] there is no need
4133 		 *	to delay again before sending the first RS
4134 		 */
4135 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4136 			return;
4137 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4138 
4139 		write_lock_bh(&ifp->idev->lock);
4140 		spin_lock(&ifp->lock);
4141 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4142 			ifp->idev->cnf.rtr_solicit_interval);
4143 		ifp->idev->rs_probes = 1;
4144 		ifp->idev->if_flags |= IF_RS_SENT;
4145 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4146 		spin_unlock(&ifp->lock);
4147 		write_unlock_bh(&ifp->idev->lock);
4148 	}
4149 
4150 	if (bump_id)
4151 		rt_genid_bump_ipv6(dev_net(dev));
4152 
4153 	/* Make sure that a new temporary address will be created
4154 	 * before this temporary address becomes deprecated.
4155 	 */
4156 	if (ifp->flags & IFA_F_TEMPORARY)
4157 		addrconf_verify_rtnl();
4158 }
4159 
4160 static void addrconf_dad_run(struct inet6_dev *idev)
4161 {
4162 	struct inet6_ifaddr *ifp;
4163 
4164 	read_lock_bh(&idev->lock);
4165 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4166 		spin_lock(&ifp->lock);
4167 		if (ifp->flags & IFA_F_TENTATIVE &&
4168 		    ifp->state == INET6_IFADDR_STATE_DAD)
4169 			addrconf_dad_kick(ifp);
4170 		spin_unlock(&ifp->lock);
4171 	}
4172 	read_unlock_bh(&idev->lock);
4173 }
4174 
4175 #ifdef CONFIG_PROC_FS
4176 struct if6_iter_state {
4177 	struct seq_net_private p;
4178 	int bucket;
4179 	int offset;
4180 };
4181 
4182 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4183 {
4184 	struct if6_iter_state *state = seq->private;
4185 	struct net *net = seq_file_net(seq);
4186 	struct inet6_ifaddr *ifa = NULL;
4187 	int p = 0;
4188 
4189 	/* initial bucket if pos is 0 */
4190 	if (pos == 0) {
4191 		state->bucket = 0;
4192 		state->offset = 0;
4193 	}
4194 
4195 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4196 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4197 					 addr_lst) {
4198 			if (!net_eq(dev_net(ifa->idev->dev), net))
4199 				continue;
4200 			/* sync with offset */
4201 			if (p < state->offset) {
4202 				p++;
4203 				continue;
4204 			}
4205 			return ifa;
4206 		}
4207 
4208 		/* prepare for next bucket */
4209 		state->offset = 0;
4210 		p = 0;
4211 	}
4212 	return NULL;
4213 }
4214 
4215 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4216 					 struct inet6_ifaddr *ifa)
4217 {
4218 	struct if6_iter_state *state = seq->private;
4219 	struct net *net = seq_file_net(seq);
4220 
4221 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4222 		if (!net_eq(dev_net(ifa->idev->dev), net))
4223 			continue;
4224 		state->offset++;
4225 		return ifa;
4226 	}
4227 
4228 	state->offset = 0;
4229 	while (++state->bucket < IN6_ADDR_HSIZE) {
4230 		hlist_for_each_entry_rcu(ifa,
4231 				     &inet6_addr_lst[state->bucket], addr_lst) {
4232 			if (!net_eq(dev_net(ifa->idev->dev), net))
4233 				continue;
4234 			return ifa;
4235 		}
4236 	}
4237 
4238 	return NULL;
4239 }
4240 
4241 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4242 	__acquires(rcu)
4243 {
4244 	rcu_read_lock();
4245 	return if6_get_first(seq, *pos);
4246 }
4247 
4248 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4249 {
4250 	struct inet6_ifaddr *ifa;
4251 
4252 	ifa = if6_get_next(seq, v);
4253 	++*pos;
4254 	return ifa;
4255 }
4256 
4257 static void if6_seq_stop(struct seq_file *seq, void *v)
4258 	__releases(rcu)
4259 {
4260 	rcu_read_unlock();
4261 }
4262 
4263 static int if6_seq_show(struct seq_file *seq, void *v)
4264 {
4265 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4266 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4267 		   &ifp->addr,
4268 		   ifp->idev->dev->ifindex,
4269 		   ifp->prefix_len,
4270 		   ifp->scope,
4271 		   (u8) ifp->flags,
4272 		   ifp->idev->dev->name);
4273 	return 0;
4274 }
4275 
4276 static const struct seq_operations if6_seq_ops = {
4277 	.start	= if6_seq_start,
4278 	.next	= if6_seq_next,
4279 	.show	= if6_seq_show,
4280 	.stop	= if6_seq_stop,
4281 };
4282 
4283 static int __net_init if6_proc_net_init(struct net *net)
4284 {
4285 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4286 			sizeof(struct if6_iter_state)))
4287 		return -ENOMEM;
4288 	return 0;
4289 }
4290 
4291 static void __net_exit if6_proc_net_exit(struct net *net)
4292 {
4293 	remove_proc_entry("if_inet6", net->proc_net);
4294 }
4295 
4296 static struct pernet_operations if6_proc_net_ops = {
4297 	.init = if6_proc_net_init,
4298 	.exit = if6_proc_net_exit,
4299 };
4300 
4301 int __init if6_proc_init(void)
4302 {
4303 	return register_pernet_subsys(&if6_proc_net_ops);
4304 }
4305 
4306 void if6_proc_exit(void)
4307 {
4308 	unregister_pernet_subsys(&if6_proc_net_ops);
4309 }
4310 #endif	/* CONFIG_PROC_FS */
4311 
4312 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4313 /* Check if address is a home address configured on any interface. */
4314 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4315 {
4316 	unsigned int hash = inet6_addr_hash(net, addr);
4317 	struct inet6_ifaddr *ifp = NULL;
4318 	int ret = 0;
4319 
4320 	rcu_read_lock();
4321 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4322 		if (!net_eq(dev_net(ifp->idev->dev), net))
4323 			continue;
4324 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4325 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4326 			ret = 1;
4327 			break;
4328 		}
4329 	}
4330 	rcu_read_unlock();
4331 	return ret;
4332 }
4333 #endif
4334 
4335 /*
4336  *	Periodic address status verification
4337  */
4338 
4339 static void addrconf_verify_rtnl(void)
4340 {
4341 	unsigned long now, next, next_sec, next_sched;
4342 	struct inet6_ifaddr *ifp;
4343 	int i;
4344 
4345 	ASSERT_RTNL();
4346 
4347 	rcu_read_lock_bh();
4348 	now = jiffies;
4349 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4350 
4351 	cancel_delayed_work(&addr_chk_work);
4352 
4353 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4354 restart:
4355 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4356 			unsigned long age;
4357 
4358 			/* When setting preferred_lft to a value not zero or
4359 			 * infinity, while valid_lft is infinity
4360 			 * IFA_F_PERMANENT has a non-infinity life time.
4361 			 */
4362 			if ((ifp->flags & IFA_F_PERMANENT) &&
4363 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4364 				continue;
4365 
4366 			spin_lock(&ifp->lock);
4367 			/* We try to batch several events at once. */
4368 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4369 
4370 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4371 			    age >= ifp->valid_lft) {
4372 				spin_unlock(&ifp->lock);
4373 				in6_ifa_hold(ifp);
4374 				ipv6_del_addr(ifp);
4375 				goto restart;
4376 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4377 				spin_unlock(&ifp->lock);
4378 				continue;
4379 			} else if (age >= ifp->prefered_lft) {
4380 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4381 				int deprecate = 0;
4382 
4383 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4384 					deprecate = 1;
4385 					ifp->flags |= IFA_F_DEPRECATED;
4386 				}
4387 
4388 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4389 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4390 					next = ifp->tstamp + ifp->valid_lft * HZ;
4391 
4392 				spin_unlock(&ifp->lock);
4393 
4394 				if (deprecate) {
4395 					in6_ifa_hold(ifp);
4396 
4397 					ipv6_ifa_notify(0, ifp);
4398 					in6_ifa_put(ifp);
4399 					goto restart;
4400 				}
4401 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4402 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4403 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4404 					ifp->idev->cnf.dad_transmits *
4405 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4406 
4407 				if (age >= ifp->prefered_lft - regen_advance) {
4408 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4409 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4410 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4411 					if (!ifp->regen_count && ifpub) {
4412 						ifp->regen_count++;
4413 						in6_ifa_hold(ifp);
4414 						in6_ifa_hold(ifpub);
4415 						spin_unlock(&ifp->lock);
4416 
4417 						spin_lock(&ifpub->lock);
4418 						ifpub->regen_count = 0;
4419 						spin_unlock(&ifpub->lock);
4420 						rcu_read_unlock_bh();
4421 						ipv6_create_tempaddr(ifpub, ifp, true);
4422 						in6_ifa_put(ifpub);
4423 						in6_ifa_put(ifp);
4424 						rcu_read_lock_bh();
4425 						goto restart;
4426 					}
4427 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4428 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4429 				spin_unlock(&ifp->lock);
4430 			} else {
4431 				/* ifp->prefered_lft <= ifp->valid_lft */
4432 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4433 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4434 				spin_unlock(&ifp->lock);
4435 			}
4436 		}
4437 	}
4438 
4439 	next_sec = round_jiffies_up(next);
4440 	next_sched = next;
4441 
4442 	/* If rounded timeout is accurate enough, accept it. */
4443 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4444 		next_sched = next_sec;
4445 
4446 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4447 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4448 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4449 
4450 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4451 		 now, next, next_sec, next_sched);
4452 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4453 	rcu_read_unlock_bh();
4454 }
4455 
4456 static void addrconf_verify_work(struct work_struct *w)
4457 {
4458 	rtnl_lock();
4459 	addrconf_verify_rtnl();
4460 	rtnl_unlock();
4461 }
4462 
4463 static void addrconf_verify(void)
4464 {
4465 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4466 }
4467 
4468 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4469 				     struct in6_addr **peer_pfx)
4470 {
4471 	struct in6_addr *pfx = NULL;
4472 
4473 	*peer_pfx = NULL;
4474 
4475 	if (addr)
4476 		pfx = nla_data(addr);
4477 
4478 	if (local) {
4479 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4480 			*peer_pfx = pfx;
4481 		pfx = nla_data(local);
4482 	}
4483 
4484 	return pfx;
4485 }
4486 
4487 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4488 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4489 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4490 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4491 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4492 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4493 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4494 };
4495 
4496 static int
4497 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4498 		  struct netlink_ext_ack *extack)
4499 {
4500 	struct net *net = sock_net(skb->sk);
4501 	struct ifaddrmsg *ifm;
4502 	struct nlattr *tb[IFA_MAX+1];
4503 	struct in6_addr *pfx, *peer_pfx;
4504 	u32 ifa_flags;
4505 	int err;
4506 
4507 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4508 			  extack);
4509 	if (err < 0)
4510 		return err;
4511 
4512 	ifm = nlmsg_data(nlh);
4513 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4514 	if (!pfx)
4515 		return -EINVAL;
4516 
4517 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4518 
4519 	/* We ignore other flags so far. */
4520 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4521 
4522 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4523 			      ifm->ifa_prefixlen);
4524 }
4525 
4526 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4527 			       unsigned long expires, u32 flags)
4528 {
4529 	struct fib6_info *f6i;
4530 	u32 prio;
4531 
4532 	f6i = addrconf_get_prefix_route(&ifp->addr,
4533 					ifp->prefix_len,
4534 					ifp->idev->dev,
4535 					0, RTF_GATEWAY | RTF_DEFAULT);
4536 	if (!f6i)
4537 		return -ENOENT;
4538 
4539 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4540 	if (f6i->fib6_metric != prio) {
4541 		/* delete old one */
4542 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4543 
4544 		/* add new one */
4545 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4546 				      ifp->rt_priority, ifp->idev->dev,
4547 				      expires, flags, GFP_KERNEL);
4548 	} else {
4549 		if (!expires)
4550 			fib6_clean_expires(f6i);
4551 		else
4552 			fib6_set_expires(f6i, expires);
4553 
4554 		fib6_info_release(f6i);
4555 	}
4556 
4557 	return 0;
4558 }
4559 
4560 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4561 {
4562 	u32 flags;
4563 	clock_t expires;
4564 	unsigned long timeout;
4565 	bool was_managetempaddr;
4566 	bool had_prefixroute;
4567 
4568 	ASSERT_RTNL();
4569 
4570 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4571 		return -EINVAL;
4572 
4573 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4574 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4575 		return -EINVAL;
4576 
4577 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4578 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4579 
4580 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4581 	if (addrconf_finite_timeout(timeout)) {
4582 		expires = jiffies_to_clock_t(timeout * HZ);
4583 		cfg->valid_lft = timeout;
4584 		flags = RTF_EXPIRES;
4585 	} else {
4586 		expires = 0;
4587 		flags = 0;
4588 		cfg->ifa_flags |= IFA_F_PERMANENT;
4589 	}
4590 
4591 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4592 	if (addrconf_finite_timeout(timeout)) {
4593 		if (timeout == 0)
4594 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4595 		cfg->preferred_lft = timeout;
4596 	}
4597 
4598 	spin_lock_bh(&ifp->lock);
4599 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4600 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4601 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4602 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4603 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4604 			IFA_F_NOPREFIXROUTE);
4605 	ifp->flags |= cfg->ifa_flags;
4606 	ifp->tstamp = jiffies;
4607 	ifp->valid_lft = cfg->valid_lft;
4608 	ifp->prefered_lft = cfg->preferred_lft;
4609 
4610 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4611 		ifp->rt_priority = cfg->rt_priority;
4612 
4613 	spin_unlock_bh(&ifp->lock);
4614 	if (!(ifp->flags&IFA_F_TENTATIVE))
4615 		ipv6_ifa_notify(0, ifp);
4616 
4617 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4618 		int rc = -ENOENT;
4619 
4620 		if (had_prefixroute)
4621 			rc = modify_prefix_route(ifp, expires, flags);
4622 
4623 		/* prefix route could have been deleted; if so restore it */
4624 		if (rc == -ENOENT) {
4625 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4626 					      ifp->rt_priority, ifp->idev->dev,
4627 					      expires, flags, GFP_KERNEL);
4628 		}
4629 	} else if (had_prefixroute) {
4630 		enum cleanup_prefix_rt_t action;
4631 		unsigned long rt_expires;
4632 
4633 		write_lock_bh(&ifp->idev->lock);
4634 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4635 		write_unlock_bh(&ifp->idev->lock);
4636 
4637 		if (action != CLEANUP_PREFIX_RT_NOP) {
4638 			cleanup_prefix_route(ifp, rt_expires,
4639 				action == CLEANUP_PREFIX_RT_DEL);
4640 		}
4641 	}
4642 
4643 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4644 		if (was_managetempaddr &&
4645 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4646 			cfg->valid_lft = 0;
4647 			cfg->preferred_lft = 0;
4648 		}
4649 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4650 				 cfg->preferred_lft, !was_managetempaddr,
4651 				 jiffies);
4652 	}
4653 
4654 	addrconf_verify_rtnl();
4655 
4656 	return 0;
4657 }
4658 
4659 static int
4660 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4661 		  struct netlink_ext_ack *extack)
4662 {
4663 	struct net *net = sock_net(skb->sk);
4664 	struct ifaddrmsg *ifm;
4665 	struct nlattr *tb[IFA_MAX+1];
4666 	struct in6_addr *peer_pfx;
4667 	struct inet6_ifaddr *ifa;
4668 	struct net_device *dev;
4669 	struct inet6_dev *idev;
4670 	struct ifa6_config cfg;
4671 	int err;
4672 
4673 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4674 			  extack);
4675 	if (err < 0)
4676 		return err;
4677 
4678 	memset(&cfg, 0, sizeof(cfg));
4679 
4680 	ifm = nlmsg_data(nlh);
4681 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4682 	if (!cfg.pfx)
4683 		return -EINVAL;
4684 
4685 	cfg.peer_pfx = peer_pfx;
4686 	cfg.plen = ifm->ifa_prefixlen;
4687 	if (tb[IFA_RT_PRIORITY])
4688 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4689 
4690 	cfg.valid_lft = INFINITY_LIFE_TIME;
4691 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4692 
4693 	if (tb[IFA_CACHEINFO]) {
4694 		struct ifa_cacheinfo *ci;
4695 
4696 		ci = nla_data(tb[IFA_CACHEINFO]);
4697 		cfg.valid_lft = ci->ifa_valid;
4698 		cfg.preferred_lft = ci->ifa_prefered;
4699 	}
4700 
4701 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4702 	if (!dev)
4703 		return -ENODEV;
4704 
4705 	if (tb[IFA_FLAGS])
4706 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4707 	else
4708 		cfg.ifa_flags = ifm->ifa_flags;
4709 
4710 	/* We ignore other flags so far. */
4711 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4712 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4713 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4714 
4715 	idev = ipv6_find_idev(dev);
4716 	if (IS_ERR(idev))
4717 		return PTR_ERR(idev);
4718 
4719 	if (!ipv6_allow_optimistic_dad(net, idev))
4720 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4721 
4722 	if (cfg.ifa_flags & IFA_F_NODAD &&
4723 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4724 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4725 		return -EINVAL;
4726 	}
4727 
4728 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4729 	if (!ifa) {
4730 		/*
4731 		 * It would be best to check for !NLM_F_CREATE here but
4732 		 * userspace already relies on not having to provide this.
4733 		 */
4734 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4735 	}
4736 
4737 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4738 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4739 		err = -EEXIST;
4740 	else
4741 		err = inet6_addr_modify(ifa, &cfg);
4742 
4743 	in6_ifa_put(ifa);
4744 
4745 	return err;
4746 }
4747 
4748 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4749 			  u8 scope, int ifindex)
4750 {
4751 	struct ifaddrmsg *ifm;
4752 
4753 	ifm = nlmsg_data(nlh);
4754 	ifm->ifa_family = AF_INET6;
4755 	ifm->ifa_prefixlen = prefixlen;
4756 	ifm->ifa_flags = flags;
4757 	ifm->ifa_scope = scope;
4758 	ifm->ifa_index = ifindex;
4759 }
4760 
4761 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4762 			 unsigned long tstamp, u32 preferred, u32 valid)
4763 {
4764 	struct ifa_cacheinfo ci;
4765 
4766 	ci.cstamp = cstamp_delta(cstamp);
4767 	ci.tstamp = cstamp_delta(tstamp);
4768 	ci.ifa_prefered = preferred;
4769 	ci.ifa_valid = valid;
4770 
4771 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4772 }
4773 
4774 static inline int rt_scope(int ifa_scope)
4775 {
4776 	if (ifa_scope & IFA_HOST)
4777 		return RT_SCOPE_HOST;
4778 	else if (ifa_scope & IFA_LINK)
4779 		return RT_SCOPE_LINK;
4780 	else if (ifa_scope & IFA_SITE)
4781 		return RT_SCOPE_SITE;
4782 	else
4783 		return RT_SCOPE_UNIVERSE;
4784 }
4785 
4786 static inline int inet6_ifaddr_msgsize(void)
4787 {
4788 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4789 	       + nla_total_size(16) /* IFA_LOCAL */
4790 	       + nla_total_size(16) /* IFA_ADDRESS */
4791 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4792 	       + nla_total_size(4)  /* IFA_FLAGS */
4793 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4794 }
4795 
4796 enum addr_type_t {
4797 	UNICAST_ADDR,
4798 	MULTICAST_ADDR,
4799 	ANYCAST_ADDR,
4800 };
4801 
4802 struct inet6_fill_args {
4803 	u32 portid;
4804 	u32 seq;
4805 	int event;
4806 	unsigned int flags;
4807 	int netnsid;
4808 	enum addr_type_t type;
4809 };
4810 
4811 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4812 			     struct inet6_fill_args *args)
4813 {
4814 	struct nlmsghdr  *nlh;
4815 	u32 preferred, valid;
4816 
4817 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4818 			sizeof(struct ifaddrmsg), args->flags);
4819 	if (!nlh)
4820 		return -EMSGSIZE;
4821 
4822 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4823 		      ifa->idev->dev->ifindex);
4824 
4825 	if (args->netnsid >= 0 &&
4826 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4827 		goto error;
4828 
4829 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4830 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4831 		preferred = ifa->prefered_lft;
4832 		valid = ifa->valid_lft;
4833 		if (preferred != INFINITY_LIFE_TIME) {
4834 			long tval = (jiffies - ifa->tstamp)/HZ;
4835 			if (preferred > tval)
4836 				preferred -= tval;
4837 			else
4838 				preferred = 0;
4839 			if (valid != INFINITY_LIFE_TIME) {
4840 				if (valid > tval)
4841 					valid -= tval;
4842 				else
4843 					valid = 0;
4844 			}
4845 		}
4846 	} else {
4847 		preferred = INFINITY_LIFE_TIME;
4848 		valid = INFINITY_LIFE_TIME;
4849 	}
4850 
4851 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4852 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4853 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4854 			goto error;
4855 	} else
4856 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4857 			goto error;
4858 
4859 	if (ifa->rt_priority &&
4860 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4861 		goto error;
4862 
4863 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4864 		goto error;
4865 
4866 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4867 		goto error;
4868 
4869 	nlmsg_end(skb, nlh);
4870 	return 0;
4871 
4872 error:
4873 	nlmsg_cancel(skb, nlh);
4874 	return -EMSGSIZE;
4875 }
4876 
4877 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4878 			       struct inet6_fill_args *args)
4879 {
4880 	struct nlmsghdr  *nlh;
4881 	u8 scope = RT_SCOPE_UNIVERSE;
4882 	int ifindex = ifmca->idev->dev->ifindex;
4883 
4884 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4885 		scope = RT_SCOPE_SITE;
4886 
4887 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4888 			sizeof(struct ifaddrmsg), args->flags);
4889 	if (!nlh)
4890 		return -EMSGSIZE;
4891 
4892 	if (args->netnsid >= 0 &&
4893 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4894 		return -EMSGSIZE;
4895 
4896 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4897 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4898 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4899 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4900 		nlmsg_cancel(skb, nlh);
4901 		return -EMSGSIZE;
4902 	}
4903 
4904 	nlmsg_end(skb, nlh);
4905 	return 0;
4906 }
4907 
4908 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4909 			       struct inet6_fill_args *args)
4910 {
4911 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4912 	int ifindex = dev ? dev->ifindex : 1;
4913 	struct nlmsghdr  *nlh;
4914 	u8 scope = RT_SCOPE_UNIVERSE;
4915 
4916 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4917 		scope = RT_SCOPE_SITE;
4918 
4919 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4920 			sizeof(struct ifaddrmsg), args->flags);
4921 	if (!nlh)
4922 		return -EMSGSIZE;
4923 
4924 	if (args->netnsid >= 0 &&
4925 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4926 		return -EMSGSIZE;
4927 
4928 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4929 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4930 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4931 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4932 		nlmsg_cancel(skb, nlh);
4933 		return -EMSGSIZE;
4934 	}
4935 
4936 	nlmsg_end(skb, nlh);
4937 	return 0;
4938 }
4939 
4940 /* called with rcu_read_lock() */
4941 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4942 			  struct netlink_callback *cb,
4943 			  int s_ip_idx, int *p_ip_idx,
4944 			  struct inet6_fill_args *fillargs)
4945 {
4946 	struct ifmcaddr6 *ifmca;
4947 	struct ifacaddr6 *ifaca;
4948 	int err = 1;
4949 	int ip_idx = *p_ip_idx;
4950 
4951 	read_lock_bh(&idev->lock);
4952 	switch (fillargs->type) {
4953 	case UNICAST_ADDR: {
4954 		struct inet6_ifaddr *ifa;
4955 		fillargs->event = RTM_NEWADDR;
4956 
4957 		/* unicast address incl. temp addr */
4958 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4959 			if (++ip_idx < s_ip_idx)
4960 				continue;
4961 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
4962 			if (err < 0)
4963 				break;
4964 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4965 		}
4966 		break;
4967 	}
4968 	case MULTICAST_ADDR:
4969 		fillargs->event = RTM_GETMULTICAST;
4970 
4971 		/* multicast address */
4972 		for (ifmca = idev->mc_list; ifmca;
4973 		     ifmca = ifmca->next, ip_idx++) {
4974 			if (ip_idx < s_ip_idx)
4975 				continue;
4976 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
4977 			if (err < 0)
4978 				break;
4979 		}
4980 		break;
4981 	case ANYCAST_ADDR:
4982 		fillargs->event = RTM_GETANYCAST;
4983 		/* anycast address */
4984 		for (ifaca = idev->ac_list; ifaca;
4985 		     ifaca = ifaca->aca_next, ip_idx++) {
4986 			if (ip_idx < s_ip_idx)
4987 				continue;
4988 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
4989 			if (err < 0)
4990 				break;
4991 		}
4992 		break;
4993 	default:
4994 		break;
4995 	}
4996 	read_unlock_bh(&idev->lock);
4997 	*p_ip_idx = ip_idx;
4998 	return err;
4999 }
5000 
5001 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5002 				       struct inet6_fill_args *fillargs,
5003 				       struct net **tgt_net, struct sock *sk,
5004 				       struct netlink_ext_ack *extack)
5005 {
5006 	struct nlattr *tb[IFA_MAX+1];
5007 	struct ifaddrmsg *ifm;
5008 	int err, i;
5009 
5010 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5011 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5012 		return -EINVAL;
5013 	}
5014 
5015 	ifm = nlmsg_data(nlh);
5016 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5017 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5018 		return -EINVAL;
5019 	}
5020 	if (ifm->ifa_index) {
5021 		NL_SET_ERR_MSG_MOD(extack, "Filter by device index not supported for address dump");
5022 		return -EINVAL;
5023 	}
5024 
5025 	err = nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5026 				 ifa_ipv6_policy, extack);
5027 	if (err < 0)
5028 		return err;
5029 
5030 	for (i = 0; i <= IFA_MAX; ++i) {
5031 		if (!tb[i])
5032 			continue;
5033 
5034 		if (i == IFA_TARGET_NETNSID) {
5035 			struct net *net;
5036 
5037 			fillargs->netnsid = nla_get_s32(tb[i]);
5038 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5039 			if (IS_ERR(net)) {
5040 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5041 				return PTR_ERR(net);
5042 			}
5043 			*tgt_net = net;
5044 		} else {
5045 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5046 			return -EINVAL;
5047 		}
5048 	}
5049 
5050 	return 0;
5051 }
5052 
5053 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5054 			   enum addr_type_t type)
5055 {
5056 	const struct nlmsghdr *nlh = cb->nlh;
5057 	struct inet6_fill_args fillargs = {
5058 		.portid = NETLINK_CB(cb->skb).portid,
5059 		.seq = cb->nlh->nlmsg_seq,
5060 		.flags = NLM_F_MULTI,
5061 		.netnsid = -1,
5062 		.type = type,
5063 	};
5064 	struct net *net = sock_net(skb->sk);
5065 	struct net *tgt_net = net;
5066 	int h, s_h;
5067 	int idx, ip_idx;
5068 	int s_idx, s_ip_idx;
5069 	struct net_device *dev;
5070 	struct inet6_dev *idev;
5071 	struct hlist_head *head;
5072 
5073 	s_h = cb->args[0];
5074 	s_idx = idx = cb->args[1];
5075 	s_ip_idx = ip_idx = cb->args[2];
5076 
5077 	if (cb->strict_check) {
5078 		int err;
5079 
5080 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5081 						  skb->sk, cb->extack);
5082 		if (err < 0)
5083 			return err;
5084 	}
5085 
5086 	rcu_read_lock();
5087 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5088 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5089 		idx = 0;
5090 		head = &tgt_net->dev_index_head[h];
5091 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5092 			if (idx < s_idx)
5093 				goto cont;
5094 			if (h > s_h || idx > s_idx)
5095 				s_ip_idx = 0;
5096 			ip_idx = 0;
5097 			idev = __in6_dev_get(dev);
5098 			if (!idev)
5099 				goto cont;
5100 
5101 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx, &ip_idx,
5102 					   &fillargs) < 0)
5103 				goto done;
5104 cont:
5105 			idx++;
5106 		}
5107 	}
5108 done:
5109 	rcu_read_unlock();
5110 	cb->args[0] = h;
5111 	cb->args[1] = idx;
5112 	cb->args[2] = ip_idx;
5113 	if (fillargs.netnsid >= 0)
5114 		put_net(tgt_net);
5115 
5116 	return skb->len;
5117 }
5118 
5119 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5120 {
5121 	enum addr_type_t type = UNICAST_ADDR;
5122 
5123 	return inet6_dump_addr(skb, cb, type);
5124 }
5125 
5126 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5127 {
5128 	enum addr_type_t type = MULTICAST_ADDR;
5129 
5130 	return inet6_dump_addr(skb, cb, type);
5131 }
5132 
5133 
5134 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5135 {
5136 	enum addr_type_t type = ANYCAST_ADDR;
5137 
5138 	return inet6_dump_addr(skb, cb, type);
5139 }
5140 
5141 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5142 			     struct netlink_ext_ack *extack)
5143 {
5144 	struct net *net = sock_net(in_skb->sk);
5145 	struct inet6_fill_args fillargs = {
5146 		.portid = NETLINK_CB(in_skb).portid,
5147 		.seq = nlh->nlmsg_seq,
5148 		.event = RTM_NEWADDR,
5149 		.flags = 0,
5150 		.netnsid = -1,
5151 	};
5152 	struct net *tgt_net = net;
5153 	struct ifaddrmsg *ifm;
5154 	struct nlattr *tb[IFA_MAX+1];
5155 	struct in6_addr *addr = NULL, *peer;
5156 	struct net_device *dev = NULL;
5157 	struct inet6_ifaddr *ifa;
5158 	struct sk_buff *skb;
5159 	int err;
5160 
5161 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
5162 			  extack);
5163 	if (err < 0)
5164 		return err;
5165 
5166 	if (tb[IFA_TARGET_NETNSID]) {
5167 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5168 
5169 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5170 						  fillargs.netnsid);
5171 		if (IS_ERR(tgt_net))
5172 			return PTR_ERR(tgt_net);
5173 	}
5174 
5175 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5176 	if (!addr)
5177 		return -EINVAL;
5178 
5179 	ifm = nlmsg_data(nlh);
5180 	if (ifm->ifa_index)
5181 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5182 
5183 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5184 	if (!ifa) {
5185 		err = -EADDRNOTAVAIL;
5186 		goto errout;
5187 	}
5188 
5189 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5190 	if (!skb) {
5191 		err = -ENOBUFS;
5192 		goto errout_ifa;
5193 	}
5194 
5195 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5196 	if (err < 0) {
5197 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5198 		WARN_ON(err == -EMSGSIZE);
5199 		kfree_skb(skb);
5200 		goto errout_ifa;
5201 	}
5202 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5203 errout_ifa:
5204 	in6_ifa_put(ifa);
5205 errout:
5206 	if (dev)
5207 		dev_put(dev);
5208 	if (fillargs.netnsid >= 0)
5209 		put_net(tgt_net);
5210 
5211 	return err;
5212 }
5213 
5214 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5215 {
5216 	struct sk_buff *skb;
5217 	struct net *net = dev_net(ifa->idev->dev);
5218 	struct inet6_fill_args fillargs = {
5219 		.portid = 0,
5220 		.seq = 0,
5221 		.event = event,
5222 		.flags = 0,
5223 		.netnsid = -1,
5224 	};
5225 	int err = -ENOBUFS;
5226 
5227 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5228 	if (!skb)
5229 		goto errout;
5230 
5231 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5232 	if (err < 0) {
5233 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5234 		WARN_ON(err == -EMSGSIZE);
5235 		kfree_skb(skb);
5236 		goto errout;
5237 	}
5238 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5239 	return;
5240 errout:
5241 	if (err < 0)
5242 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5243 }
5244 
5245 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5246 				__s32 *array, int bytes)
5247 {
5248 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5249 
5250 	memset(array, 0, bytes);
5251 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5252 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5253 	array[DEVCONF_MTU6] = cnf->mtu6;
5254 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5255 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5256 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5257 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5258 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5259 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5260 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5261 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5262 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5263 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5264 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5265 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5266 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5267 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5268 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5269 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5270 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5271 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5272 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5273 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5274 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5275 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5276 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5277 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5278 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5279 #ifdef CONFIG_IPV6_ROUTER_PREF
5280 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5281 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5282 		jiffies_to_msecs(cnf->rtr_probe_interval);
5283 #ifdef CONFIG_IPV6_ROUTE_INFO
5284 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5285 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5286 #endif
5287 #endif
5288 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5289 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5290 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5291 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5292 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5293 #endif
5294 #ifdef CONFIG_IPV6_MROUTE
5295 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5296 #endif
5297 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5298 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5299 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5300 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5301 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5302 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5303 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5304 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5305 	/* we omit DEVCONF_STABLE_SECRET for now */
5306 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5307 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5308 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5309 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5310 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5311 #ifdef CONFIG_IPV6_SEG6_HMAC
5312 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5313 #endif
5314 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5315 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5316 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5317 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5318 }
5319 
5320 static inline size_t inet6_ifla6_size(void)
5321 {
5322 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5323 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5324 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5325 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5326 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5327 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5328 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5329 	     + 0;
5330 }
5331 
5332 static inline size_t inet6_if_nlmsg_size(void)
5333 {
5334 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5335 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5336 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5337 	       + nla_total_size(4) /* IFLA_MTU */
5338 	       + nla_total_size(4) /* IFLA_LINK */
5339 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5340 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5341 }
5342 
5343 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5344 					int bytes)
5345 {
5346 	int i;
5347 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5348 	BUG_ON(pad < 0);
5349 
5350 	/* Use put_unaligned() because stats may not be aligned for u64. */
5351 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5352 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5353 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5354 
5355 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5356 }
5357 
5358 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5359 					int bytes, size_t syncpoff)
5360 {
5361 	int i, c;
5362 	u64 buff[IPSTATS_MIB_MAX];
5363 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5364 
5365 	BUG_ON(pad < 0);
5366 
5367 	memset(buff, 0, sizeof(buff));
5368 	buff[0] = IPSTATS_MIB_MAX;
5369 
5370 	for_each_possible_cpu(c) {
5371 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5372 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5373 	}
5374 
5375 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5376 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5377 }
5378 
5379 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5380 			     int bytes)
5381 {
5382 	switch (attrtype) {
5383 	case IFLA_INET6_STATS:
5384 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5385 				     offsetof(struct ipstats_mib, syncp));
5386 		break;
5387 	case IFLA_INET6_ICMP6STATS:
5388 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5389 		break;
5390 	}
5391 }
5392 
5393 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5394 				  u32 ext_filter_mask)
5395 {
5396 	struct nlattr *nla;
5397 	struct ifla_cacheinfo ci;
5398 
5399 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5400 		goto nla_put_failure;
5401 	ci.max_reasm_len = IPV6_MAXPLEN;
5402 	ci.tstamp = cstamp_delta(idev->tstamp);
5403 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5404 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5405 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5406 		goto nla_put_failure;
5407 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5408 	if (!nla)
5409 		goto nla_put_failure;
5410 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5411 
5412 	/* XXX - MC not implemented */
5413 
5414 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5415 		return 0;
5416 
5417 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5418 	if (!nla)
5419 		goto nla_put_failure;
5420 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5421 
5422 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5423 	if (!nla)
5424 		goto nla_put_failure;
5425 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5426 
5427 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5428 	if (!nla)
5429 		goto nla_put_failure;
5430 
5431 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5432 		goto nla_put_failure;
5433 
5434 	read_lock_bh(&idev->lock);
5435 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5436 	read_unlock_bh(&idev->lock);
5437 
5438 	return 0;
5439 
5440 nla_put_failure:
5441 	return -EMSGSIZE;
5442 }
5443 
5444 static size_t inet6_get_link_af_size(const struct net_device *dev,
5445 				     u32 ext_filter_mask)
5446 {
5447 	if (!__in6_dev_get(dev))
5448 		return 0;
5449 
5450 	return inet6_ifla6_size();
5451 }
5452 
5453 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5454 			      u32 ext_filter_mask)
5455 {
5456 	struct inet6_dev *idev = __in6_dev_get(dev);
5457 
5458 	if (!idev)
5459 		return -ENODATA;
5460 
5461 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5462 		return -EMSGSIZE;
5463 
5464 	return 0;
5465 }
5466 
5467 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5468 {
5469 	struct inet6_ifaddr *ifp;
5470 	struct net_device *dev = idev->dev;
5471 	bool clear_token, update_rs = false;
5472 	struct in6_addr ll_addr;
5473 
5474 	ASSERT_RTNL();
5475 
5476 	if (!token)
5477 		return -EINVAL;
5478 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5479 		return -EINVAL;
5480 	if (!ipv6_accept_ra(idev))
5481 		return -EINVAL;
5482 	if (idev->cnf.rtr_solicits == 0)
5483 		return -EINVAL;
5484 
5485 	write_lock_bh(&idev->lock);
5486 
5487 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5488 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5489 
5490 	write_unlock_bh(&idev->lock);
5491 
5492 	clear_token = ipv6_addr_any(token);
5493 	if (clear_token)
5494 		goto update_lft;
5495 
5496 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5497 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5498 			     IFA_F_OPTIMISTIC)) {
5499 		/* If we're not ready, then normal ifup will take care
5500 		 * of this. Otherwise, we need to request our rs here.
5501 		 */
5502 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5503 		update_rs = true;
5504 	}
5505 
5506 update_lft:
5507 	write_lock_bh(&idev->lock);
5508 
5509 	if (update_rs) {
5510 		idev->if_flags |= IF_RS_SENT;
5511 		idev->rs_interval = rfc3315_s14_backoff_init(
5512 			idev->cnf.rtr_solicit_interval);
5513 		idev->rs_probes = 1;
5514 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5515 	}
5516 
5517 	/* Well, that's kinda nasty ... */
5518 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5519 		spin_lock(&ifp->lock);
5520 		if (ifp->tokenized) {
5521 			ifp->valid_lft = 0;
5522 			ifp->prefered_lft = 0;
5523 		}
5524 		spin_unlock(&ifp->lock);
5525 	}
5526 
5527 	write_unlock_bh(&idev->lock);
5528 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5529 	addrconf_verify_rtnl();
5530 	return 0;
5531 }
5532 
5533 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5534 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5535 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5536 };
5537 
5538 static int inet6_validate_link_af(const struct net_device *dev,
5539 				  const struct nlattr *nla)
5540 {
5541 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5542 
5543 	if (dev && !__in6_dev_get(dev))
5544 		return -EAFNOSUPPORT;
5545 
5546 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5547 				NULL);
5548 }
5549 
5550 static int check_addr_gen_mode(int mode)
5551 {
5552 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5553 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5554 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5555 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5556 		return -EINVAL;
5557 	return 1;
5558 }
5559 
5560 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5561 				int mode)
5562 {
5563 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5564 	    !idev->cnf.stable_secret.initialized &&
5565 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5566 		return -EINVAL;
5567 	return 1;
5568 }
5569 
5570 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5571 {
5572 	int err = -EINVAL;
5573 	struct inet6_dev *idev = __in6_dev_get(dev);
5574 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5575 
5576 	if (!idev)
5577 		return -EAFNOSUPPORT;
5578 
5579 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5580 		BUG();
5581 
5582 	if (tb[IFLA_INET6_TOKEN]) {
5583 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5584 		if (err)
5585 			return err;
5586 	}
5587 
5588 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5589 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5590 
5591 		if (check_addr_gen_mode(mode) < 0 ||
5592 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5593 			return -EINVAL;
5594 
5595 		idev->cnf.addr_gen_mode = mode;
5596 		err = 0;
5597 	}
5598 
5599 	return err;
5600 }
5601 
5602 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5603 			     u32 portid, u32 seq, int event, unsigned int flags)
5604 {
5605 	struct net_device *dev = idev->dev;
5606 	struct ifinfomsg *hdr;
5607 	struct nlmsghdr *nlh;
5608 	void *protoinfo;
5609 
5610 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5611 	if (!nlh)
5612 		return -EMSGSIZE;
5613 
5614 	hdr = nlmsg_data(nlh);
5615 	hdr->ifi_family = AF_INET6;
5616 	hdr->__ifi_pad = 0;
5617 	hdr->ifi_type = dev->type;
5618 	hdr->ifi_index = dev->ifindex;
5619 	hdr->ifi_flags = dev_get_flags(dev);
5620 	hdr->ifi_change = 0;
5621 
5622 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5623 	    (dev->addr_len &&
5624 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5625 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5626 	    (dev->ifindex != dev_get_iflink(dev) &&
5627 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5628 	    nla_put_u8(skb, IFLA_OPERSTATE,
5629 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5630 		goto nla_put_failure;
5631 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5632 	if (!protoinfo)
5633 		goto nla_put_failure;
5634 
5635 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5636 		goto nla_put_failure;
5637 
5638 	nla_nest_end(skb, protoinfo);
5639 	nlmsg_end(skb, nlh);
5640 	return 0;
5641 
5642 nla_put_failure:
5643 	nlmsg_cancel(skb, nlh);
5644 	return -EMSGSIZE;
5645 }
5646 
5647 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5648 				   struct netlink_ext_ack *extack)
5649 {
5650 	struct ifinfomsg *ifm;
5651 
5652 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5653 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5654 		return -EINVAL;
5655 	}
5656 
5657 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5658 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5659 		return -EINVAL;
5660 	}
5661 
5662 	ifm = nlmsg_data(nlh);
5663 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5664 	    ifm->ifi_change || ifm->ifi_index) {
5665 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5666 		return -EINVAL;
5667 	}
5668 
5669 	return 0;
5670 }
5671 
5672 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5673 {
5674 	struct net *net = sock_net(skb->sk);
5675 	int h, s_h;
5676 	int idx = 0, s_idx;
5677 	struct net_device *dev;
5678 	struct inet6_dev *idev;
5679 	struct hlist_head *head;
5680 
5681 	/* only requests using strict checking can pass data to
5682 	 * influence the dump
5683 	 */
5684 	if (cb->strict_check) {
5685 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5686 
5687 		if (err < 0)
5688 			return err;
5689 	}
5690 
5691 	s_h = cb->args[0];
5692 	s_idx = cb->args[1];
5693 
5694 	rcu_read_lock();
5695 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5696 		idx = 0;
5697 		head = &net->dev_index_head[h];
5698 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5699 			if (idx < s_idx)
5700 				goto cont;
5701 			idev = __in6_dev_get(dev);
5702 			if (!idev)
5703 				goto cont;
5704 			if (inet6_fill_ifinfo(skb, idev,
5705 					      NETLINK_CB(cb->skb).portid,
5706 					      cb->nlh->nlmsg_seq,
5707 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5708 				goto out;
5709 cont:
5710 			idx++;
5711 		}
5712 	}
5713 out:
5714 	rcu_read_unlock();
5715 	cb->args[1] = idx;
5716 	cb->args[0] = h;
5717 
5718 	return skb->len;
5719 }
5720 
5721 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5722 {
5723 	struct sk_buff *skb;
5724 	struct net *net = dev_net(idev->dev);
5725 	int err = -ENOBUFS;
5726 
5727 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5728 	if (!skb)
5729 		goto errout;
5730 
5731 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5732 	if (err < 0) {
5733 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5734 		WARN_ON(err == -EMSGSIZE);
5735 		kfree_skb(skb);
5736 		goto errout;
5737 	}
5738 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5739 	return;
5740 errout:
5741 	if (err < 0)
5742 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5743 }
5744 
5745 static inline size_t inet6_prefix_nlmsg_size(void)
5746 {
5747 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5748 	       + nla_total_size(sizeof(struct in6_addr))
5749 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5750 }
5751 
5752 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5753 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5754 			     int event, unsigned int flags)
5755 {
5756 	struct prefixmsg *pmsg;
5757 	struct nlmsghdr *nlh;
5758 	struct prefix_cacheinfo	ci;
5759 
5760 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5761 	if (!nlh)
5762 		return -EMSGSIZE;
5763 
5764 	pmsg = nlmsg_data(nlh);
5765 	pmsg->prefix_family = AF_INET6;
5766 	pmsg->prefix_pad1 = 0;
5767 	pmsg->prefix_pad2 = 0;
5768 	pmsg->prefix_ifindex = idev->dev->ifindex;
5769 	pmsg->prefix_len = pinfo->prefix_len;
5770 	pmsg->prefix_type = pinfo->type;
5771 	pmsg->prefix_pad3 = 0;
5772 	pmsg->prefix_flags = 0;
5773 	if (pinfo->onlink)
5774 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5775 	if (pinfo->autoconf)
5776 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5777 
5778 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5779 		goto nla_put_failure;
5780 	ci.preferred_time = ntohl(pinfo->prefered);
5781 	ci.valid_time = ntohl(pinfo->valid);
5782 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5783 		goto nla_put_failure;
5784 	nlmsg_end(skb, nlh);
5785 	return 0;
5786 
5787 nla_put_failure:
5788 	nlmsg_cancel(skb, nlh);
5789 	return -EMSGSIZE;
5790 }
5791 
5792 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5793 			 struct prefix_info *pinfo)
5794 {
5795 	struct sk_buff *skb;
5796 	struct net *net = dev_net(idev->dev);
5797 	int err = -ENOBUFS;
5798 
5799 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5800 	if (!skb)
5801 		goto errout;
5802 
5803 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5804 	if (err < 0) {
5805 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5806 		WARN_ON(err == -EMSGSIZE);
5807 		kfree_skb(skb);
5808 		goto errout;
5809 	}
5810 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5811 	return;
5812 errout:
5813 	if (err < 0)
5814 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5815 }
5816 
5817 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5818 {
5819 	struct net *net = dev_net(ifp->idev->dev);
5820 
5821 	if (event)
5822 		ASSERT_RTNL();
5823 
5824 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5825 
5826 	switch (event) {
5827 	case RTM_NEWADDR:
5828 		/*
5829 		 * If the address was optimistic
5830 		 * we inserted the route at the start of
5831 		 * our DAD process, so we don't need
5832 		 * to do it again
5833 		 */
5834 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5835 			ip6_ins_rt(net, ifp->rt);
5836 		if (ifp->idev->cnf.forwarding)
5837 			addrconf_join_anycast(ifp);
5838 		if (!ipv6_addr_any(&ifp->peer_addr))
5839 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5840 					      ifp->idev->dev, 0, 0,
5841 					      GFP_ATOMIC);
5842 		break;
5843 	case RTM_DELADDR:
5844 		if (ifp->idev->cnf.forwarding)
5845 			addrconf_leave_anycast(ifp);
5846 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5847 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5848 			struct fib6_info *rt;
5849 
5850 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5851 						       ifp->idev->dev, 0, 0);
5852 			if (rt)
5853 				ip6_del_rt(net, rt);
5854 		}
5855 		if (ifp->rt) {
5856 			ip6_del_rt(net, ifp->rt);
5857 			ifp->rt = NULL;
5858 		}
5859 		rt_genid_bump_ipv6(net);
5860 		break;
5861 	}
5862 	atomic_inc(&net->ipv6.dev_addr_genid);
5863 }
5864 
5865 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5866 {
5867 	rcu_read_lock_bh();
5868 	if (likely(ifp->idev->dead == 0))
5869 		__ipv6_ifa_notify(event, ifp);
5870 	rcu_read_unlock_bh();
5871 }
5872 
5873 #ifdef CONFIG_SYSCTL
5874 
5875 static
5876 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5877 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5878 {
5879 	int *valp = ctl->data;
5880 	int val = *valp;
5881 	loff_t pos = *ppos;
5882 	struct ctl_table lctl;
5883 	int ret;
5884 
5885 	/*
5886 	 * ctl->data points to idev->cnf.forwarding, we should
5887 	 * not modify it until we get the rtnl lock.
5888 	 */
5889 	lctl = *ctl;
5890 	lctl.data = &val;
5891 
5892 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5893 
5894 	if (write)
5895 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5896 	if (ret)
5897 		*ppos = pos;
5898 	return ret;
5899 }
5900 
5901 static
5902 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5903 			void __user *buffer, size_t *lenp, loff_t *ppos)
5904 {
5905 	struct inet6_dev *idev = ctl->extra1;
5906 	int min_mtu = IPV6_MIN_MTU;
5907 	struct ctl_table lctl;
5908 
5909 	lctl = *ctl;
5910 	lctl.extra1 = &min_mtu;
5911 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5912 
5913 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5914 }
5915 
5916 static void dev_disable_change(struct inet6_dev *idev)
5917 {
5918 	struct netdev_notifier_info info;
5919 
5920 	if (!idev || !idev->dev)
5921 		return;
5922 
5923 	netdev_notifier_info_init(&info, idev->dev);
5924 	if (idev->cnf.disable_ipv6)
5925 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5926 	else
5927 		addrconf_notify(NULL, NETDEV_UP, &info);
5928 }
5929 
5930 static void addrconf_disable_change(struct net *net, __s32 newf)
5931 {
5932 	struct net_device *dev;
5933 	struct inet6_dev *idev;
5934 
5935 	for_each_netdev(net, dev) {
5936 		idev = __in6_dev_get(dev);
5937 		if (idev) {
5938 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5939 			idev->cnf.disable_ipv6 = newf;
5940 			if (changed)
5941 				dev_disable_change(idev);
5942 		}
5943 	}
5944 }
5945 
5946 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5947 {
5948 	struct net *net;
5949 	int old;
5950 
5951 	if (!rtnl_trylock())
5952 		return restart_syscall();
5953 
5954 	net = (struct net *)table->extra2;
5955 	old = *p;
5956 	*p = newf;
5957 
5958 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5959 		rtnl_unlock();
5960 		return 0;
5961 	}
5962 
5963 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5964 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5965 		addrconf_disable_change(net, newf);
5966 	} else if ((!newf) ^ (!old))
5967 		dev_disable_change((struct inet6_dev *)table->extra1);
5968 
5969 	rtnl_unlock();
5970 	return 0;
5971 }
5972 
5973 static
5974 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5975 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5976 {
5977 	int *valp = ctl->data;
5978 	int val = *valp;
5979 	loff_t pos = *ppos;
5980 	struct ctl_table lctl;
5981 	int ret;
5982 
5983 	/*
5984 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5985 	 * not modify it until we get the rtnl lock.
5986 	 */
5987 	lctl = *ctl;
5988 	lctl.data = &val;
5989 
5990 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5991 
5992 	if (write)
5993 		ret = addrconf_disable_ipv6(ctl, valp, val);
5994 	if (ret)
5995 		*ppos = pos;
5996 	return ret;
5997 }
5998 
5999 static
6000 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6001 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6002 {
6003 	int *valp = ctl->data;
6004 	int ret;
6005 	int old, new;
6006 
6007 	old = *valp;
6008 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6009 	new = *valp;
6010 
6011 	if (write && old != new) {
6012 		struct net *net = ctl->extra2;
6013 
6014 		if (!rtnl_trylock())
6015 			return restart_syscall();
6016 
6017 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6018 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6019 						     NETCONFA_PROXY_NEIGH,
6020 						     NETCONFA_IFINDEX_DEFAULT,
6021 						     net->ipv6.devconf_dflt);
6022 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6023 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6024 						     NETCONFA_PROXY_NEIGH,
6025 						     NETCONFA_IFINDEX_ALL,
6026 						     net->ipv6.devconf_all);
6027 		else {
6028 			struct inet6_dev *idev = ctl->extra1;
6029 
6030 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6031 						     NETCONFA_PROXY_NEIGH,
6032 						     idev->dev->ifindex,
6033 						     &idev->cnf);
6034 		}
6035 		rtnl_unlock();
6036 	}
6037 
6038 	return ret;
6039 }
6040 
6041 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6042 					 void __user *buffer, size_t *lenp,
6043 					 loff_t *ppos)
6044 {
6045 	int ret = 0;
6046 	u32 new_val;
6047 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6048 	struct net *net = (struct net *)ctl->extra2;
6049 	struct ctl_table tmp = {
6050 		.data = &new_val,
6051 		.maxlen = sizeof(new_val),
6052 		.mode = ctl->mode,
6053 	};
6054 
6055 	if (!rtnl_trylock())
6056 		return restart_syscall();
6057 
6058 	new_val = *((u32 *)ctl->data);
6059 
6060 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6061 	if (ret != 0)
6062 		goto out;
6063 
6064 	if (write) {
6065 		if (check_addr_gen_mode(new_val) < 0) {
6066 			ret = -EINVAL;
6067 			goto out;
6068 		}
6069 
6070 		if (idev) {
6071 			if (check_stable_privacy(idev, net, new_val) < 0) {
6072 				ret = -EINVAL;
6073 				goto out;
6074 			}
6075 
6076 			if (idev->cnf.addr_gen_mode != new_val) {
6077 				idev->cnf.addr_gen_mode = new_val;
6078 				addrconf_dev_config(idev->dev);
6079 			}
6080 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6081 			struct net_device *dev;
6082 
6083 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6084 			for_each_netdev(net, dev) {
6085 				idev = __in6_dev_get(dev);
6086 				if (idev &&
6087 				    idev->cnf.addr_gen_mode != new_val) {
6088 					idev->cnf.addr_gen_mode = new_val;
6089 					addrconf_dev_config(idev->dev);
6090 				}
6091 			}
6092 		}
6093 
6094 		*((u32 *)ctl->data) = new_val;
6095 	}
6096 
6097 out:
6098 	rtnl_unlock();
6099 
6100 	return ret;
6101 }
6102 
6103 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6104 					 void __user *buffer, size_t *lenp,
6105 					 loff_t *ppos)
6106 {
6107 	int err;
6108 	struct in6_addr addr;
6109 	char str[IPV6_MAX_STRLEN];
6110 	struct ctl_table lctl = *ctl;
6111 	struct net *net = ctl->extra2;
6112 	struct ipv6_stable_secret *secret = ctl->data;
6113 
6114 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6115 		return -EIO;
6116 
6117 	lctl.maxlen = IPV6_MAX_STRLEN;
6118 	lctl.data = str;
6119 
6120 	if (!rtnl_trylock())
6121 		return restart_syscall();
6122 
6123 	if (!write && !secret->initialized) {
6124 		err = -EIO;
6125 		goto out;
6126 	}
6127 
6128 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6129 	if (err >= sizeof(str)) {
6130 		err = -EIO;
6131 		goto out;
6132 	}
6133 
6134 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6135 	if (err || !write)
6136 		goto out;
6137 
6138 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6139 		err = -EIO;
6140 		goto out;
6141 	}
6142 
6143 	secret->initialized = true;
6144 	secret->secret = addr;
6145 
6146 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6147 		struct net_device *dev;
6148 
6149 		for_each_netdev(net, dev) {
6150 			struct inet6_dev *idev = __in6_dev_get(dev);
6151 
6152 			if (idev) {
6153 				idev->cnf.addr_gen_mode =
6154 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6155 			}
6156 		}
6157 	} else {
6158 		struct inet6_dev *idev = ctl->extra1;
6159 
6160 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6161 	}
6162 
6163 out:
6164 	rtnl_unlock();
6165 
6166 	return err;
6167 }
6168 
6169 static
6170 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6171 						int write,
6172 						void __user *buffer,
6173 						size_t *lenp,
6174 						loff_t *ppos)
6175 {
6176 	int *valp = ctl->data;
6177 	int val = *valp;
6178 	loff_t pos = *ppos;
6179 	struct ctl_table lctl;
6180 	int ret;
6181 
6182 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6183 	 * we should not modify it until we get the rtnl lock.
6184 	 */
6185 	lctl = *ctl;
6186 	lctl.data = &val;
6187 
6188 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6189 
6190 	if (write)
6191 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6192 	if (ret)
6193 		*ppos = pos;
6194 	return ret;
6195 }
6196 
6197 static
6198 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6199 {
6200 	if (rt) {
6201 		if (action)
6202 			rt->dst.flags |= DST_NOPOLICY;
6203 		else
6204 			rt->dst.flags &= ~DST_NOPOLICY;
6205 	}
6206 }
6207 
6208 static
6209 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6210 {
6211 	struct inet6_ifaddr *ifa;
6212 
6213 	read_lock_bh(&idev->lock);
6214 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6215 		spin_lock(&ifa->lock);
6216 		if (ifa->rt) {
6217 			struct fib6_info *rt = ifa->rt;
6218 			int cpu;
6219 
6220 			rcu_read_lock();
6221 			ifa->rt->dst_nopolicy = val ? true : false;
6222 			if (rt->rt6i_pcpu) {
6223 				for_each_possible_cpu(cpu) {
6224 					struct rt6_info **rtp;
6225 
6226 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6227 					addrconf_set_nopolicy(*rtp, val);
6228 				}
6229 			}
6230 			rcu_read_unlock();
6231 		}
6232 		spin_unlock(&ifa->lock);
6233 	}
6234 	read_unlock_bh(&idev->lock);
6235 }
6236 
6237 static
6238 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6239 {
6240 	struct inet6_dev *idev;
6241 	struct net *net;
6242 
6243 	if (!rtnl_trylock())
6244 		return restart_syscall();
6245 
6246 	*valp = val;
6247 
6248 	net = (struct net *)ctl->extra2;
6249 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6250 		rtnl_unlock();
6251 		return 0;
6252 	}
6253 
6254 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6255 		struct net_device *dev;
6256 
6257 		for_each_netdev(net, dev) {
6258 			idev = __in6_dev_get(dev);
6259 			if (idev)
6260 				addrconf_disable_policy_idev(idev, val);
6261 		}
6262 	} else {
6263 		idev = (struct inet6_dev *)ctl->extra1;
6264 		addrconf_disable_policy_idev(idev, val);
6265 	}
6266 
6267 	rtnl_unlock();
6268 	return 0;
6269 }
6270 
6271 static
6272 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6273 				   void __user *buffer, size_t *lenp,
6274 				   loff_t *ppos)
6275 {
6276 	int *valp = ctl->data;
6277 	int val = *valp;
6278 	loff_t pos = *ppos;
6279 	struct ctl_table lctl;
6280 	int ret;
6281 
6282 	lctl = *ctl;
6283 	lctl.data = &val;
6284 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6285 
6286 	if (write && (*valp != val))
6287 		ret = addrconf_disable_policy(ctl, valp, val);
6288 
6289 	if (ret)
6290 		*ppos = pos;
6291 
6292 	return ret;
6293 }
6294 
6295 static int minus_one = -1;
6296 static const int zero = 0;
6297 static const int one = 1;
6298 static const int two_five_five = 255;
6299 
6300 static const struct ctl_table addrconf_sysctl[] = {
6301 	{
6302 		.procname	= "forwarding",
6303 		.data		= &ipv6_devconf.forwarding,
6304 		.maxlen		= sizeof(int),
6305 		.mode		= 0644,
6306 		.proc_handler	= addrconf_sysctl_forward,
6307 	},
6308 	{
6309 		.procname	= "hop_limit",
6310 		.data		= &ipv6_devconf.hop_limit,
6311 		.maxlen		= sizeof(int),
6312 		.mode		= 0644,
6313 		.proc_handler	= proc_dointvec_minmax,
6314 		.extra1		= (void *)&one,
6315 		.extra2		= (void *)&two_five_five,
6316 	},
6317 	{
6318 		.procname	= "mtu",
6319 		.data		= &ipv6_devconf.mtu6,
6320 		.maxlen		= sizeof(int),
6321 		.mode		= 0644,
6322 		.proc_handler	= addrconf_sysctl_mtu,
6323 	},
6324 	{
6325 		.procname	= "accept_ra",
6326 		.data		= &ipv6_devconf.accept_ra,
6327 		.maxlen		= sizeof(int),
6328 		.mode		= 0644,
6329 		.proc_handler	= proc_dointvec,
6330 	},
6331 	{
6332 		.procname	= "accept_redirects",
6333 		.data		= &ipv6_devconf.accept_redirects,
6334 		.maxlen		= sizeof(int),
6335 		.mode		= 0644,
6336 		.proc_handler	= proc_dointvec,
6337 	},
6338 	{
6339 		.procname	= "autoconf",
6340 		.data		= &ipv6_devconf.autoconf,
6341 		.maxlen		= sizeof(int),
6342 		.mode		= 0644,
6343 		.proc_handler	= proc_dointvec,
6344 	},
6345 	{
6346 		.procname	= "dad_transmits",
6347 		.data		= &ipv6_devconf.dad_transmits,
6348 		.maxlen		= sizeof(int),
6349 		.mode		= 0644,
6350 		.proc_handler	= proc_dointvec,
6351 	},
6352 	{
6353 		.procname	= "router_solicitations",
6354 		.data		= &ipv6_devconf.rtr_solicits,
6355 		.maxlen		= sizeof(int),
6356 		.mode		= 0644,
6357 		.proc_handler	= proc_dointvec_minmax,
6358 		.extra1		= &minus_one,
6359 	},
6360 	{
6361 		.procname	= "router_solicitation_interval",
6362 		.data		= &ipv6_devconf.rtr_solicit_interval,
6363 		.maxlen		= sizeof(int),
6364 		.mode		= 0644,
6365 		.proc_handler	= proc_dointvec_jiffies,
6366 	},
6367 	{
6368 		.procname	= "router_solicitation_max_interval",
6369 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6370 		.maxlen		= sizeof(int),
6371 		.mode		= 0644,
6372 		.proc_handler	= proc_dointvec_jiffies,
6373 	},
6374 	{
6375 		.procname	= "router_solicitation_delay",
6376 		.data		= &ipv6_devconf.rtr_solicit_delay,
6377 		.maxlen		= sizeof(int),
6378 		.mode		= 0644,
6379 		.proc_handler	= proc_dointvec_jiffies,
6380 	},
6381 	{
6382 		.procname	= "force_mld_version",
6383 		.data		= &ipv6_devconf.force_mld_version,
6384 		.maxlen		= sizeof(int),
6385 		.mode		= 0644,
6386 		.proc_handler	= proc_dointvec,
6387 	},
6388 	{
6389 		.procname	= "mldv1_unsolicited_report_interval",
6390 		.data		=
6391 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6392 		.maxlen		= sizeof(int),
6393 		.mode		= 0644,
6394 		.proc_handler	= proc_dointvec_ms_jiffies,
6395 	},
6396 	{
6397 		.procname	= "mldv2_unsolicited_report_interval",
6398 		.data		=
6399 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6400 		.maxlen		= sizeof(int),
6401 		.mode		= 0644,
6402 		.proc_handler	= proc_dointvec_ms_jiffies,
6403 	},
6404 	{
6405 		.procname	= "use_tempaddr",
6406 		.data		= &ipv6_devconf.use_tempaddr,
6407 		.maxlen		= sizeof(int),
6408 		.mode		= 0644,
6409 		.proc_handler	= proc_dointvec,
6410 	},
6411 	{
6412 		.procname	= "temp_valid_lft",
6413 		.data		= &ipv6_devconf.temp_valid_lft,
6414 		.maxlen		= sizeof(int),
6415 		.mode		= 0644,
6416 		.proc_handler	= proc_dointvec,
6417 	},
6418 	{
6419 		.procname	= "temp_prefered_lft",
6420 		.data		= &ipv6_devconf.temp_prefered_lft,
6421 		.maxlen		= sizeof(int),
6422 		.mode		= 0644,
6423 		.proc_handler	= proc_dointvec,
6424 	},
6425 	{
6426 		.procname	= "regen_max_retry",
6427 		.data		= &ipv6_devconf.regen_max_retry,
6428 		.maxlen		= sizeof(int),
6429 		.mode		= 0644,
6430 		.proc_handler	= proc_dointvec,
6431 	},
6432 	{
6433 		.procname	= "max_desync_factor",
6434 		.data		= &ipv6_devconf.max_desync_factor,
6435 		.maxlen		= sizeof(int),
6436 		.mode		= 0644,
6437 		.proc_handler	= proc_dointvec,
6438 	},
6439 	{
6440 		.procname	= "max_addresses",
6441 		.data		= &ipv6_devconf.max_addresses,
6442 		.maxlen		= sizeof(int),
6443 		.mode		= 0644,
6444 		.proc_handler	= proc_dointvec,
6445 	},
6446 	{
6447 		.procname	= "accept_ra_defrtr",
6448 		.data		= &ipv6_devconf.accept_ra_defrtr,
6449 		.maxlen		= sizeof(int),
6450 		.mode		= 0644,
6451 		.proc_handler	= proc_dointvec,
6452 	},
6453 	{
6454 		.procname	= "accept_ra_min_hop_limit",
6455 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6456 		.maxlen		= sizeof(int),
6457 		.mode		= 0644,
6458 		.proc_handler	= proc_dointvec,
6459 	},
6460 	{
6461 		.procname	= "accept_ra_pinfo",
6462 		.data		= &ipv6_devconf.accept_ra_pinfo,
6463 		.maxlen		= sizeof(int),
6464 		.mode		= 0644,
6465 		.proc_handler	= proc_dointvec,
6466 	},
6467 #ifdef CONFIG_IPV6_ROUTER_PREF
6468 	{
6469 		.procname	= "accept_ra_rtr_pref",
6470 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6471 		.maxlen		= sizeof(int),
6472 		.mode		= 0644,
6473 		.proc_handler	= proc_dointvec,
6474 	},
6475 	{
6476 		.procname	= "router_probe_interval",
6477 		.data		= &ipv6_devconf.rtr_probe_interval,
6478 		.maxlen		= sizeof(int),
6479 		.mode		= 0644,
6480 		.proc_handler	= proc_dointvec_jiffies,
6481 	},
6482 #ifdef CONFIG_IPV6_ROUTE_INFO
6483 	{
6484 		.procname	= "accept_ra_rt_info_min_plen",
6485 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6486 		.maxlen		= sizeof(int),
6487 		.mode		= 0644,
6488 		.proc_handler	= proc_dointvec,
6489 	},
6490 	{
6491 		.procname	= "accept_ra_rt_info_max_plen",
6492 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6493 		.maxlen		= sizeof(int),
6494 		.mode		= 0644,
6495 		.proc_handler	= proc_dointvec,
6496 	},
6497 #endif
6498 #endif
6499 	{
6500 		.procname	= "proxy_ndp",
6501 		.data		= &ipv6_devconf.proxy_ndp,
6502 		.maxlen		= sizeof(int),
6503 		.mode		= 0644,
6504 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6505 	},
6506 	{
6507 		.procname	= "accept_source_route",
6508 		.data		= &ipv6_devconf.accept_source_route,
6509 		.maxlen		= sizeof(int),
6510 		.mode		= 0644,
6511 		.proc_handler	= proc_dointvec,
6512 	},
6513 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6514 	{
6515 		.procname	= "optimistic_dad",
6516 		.data		= &ipv6_devconf.optimistic_dad,
6517 		.maxlen		= sizeof(int),
6518 		.mode		= 0644,
6519 		.proc_handler   = proc_dointvec,
6520 	},
6521 	{
6522 		.procname	= "use_optimistic",
6523 		.data		= &ipv6_devconf.use_optimistic,
6524 		.maxlen		= sizeof(int),
6525 		.mode		= 0644,
6526 		.proc_handler	= proc_dointvec,
6527 	},
6528 #endif
6529 #ifdef CONFIG_IPV6_MROUTE
6530 	{
6531 		.procname	= "mc_forwarding",
6532 		.data		= &ipv6_devconf.mc_forwarding,
6533 		.maxlen		= sizeof(int),
6534 		.mode		= 0444,
6535 		.proc_handler	= proc_dointvec,
6536 	},
6537 #endif
6538 	{
6539 		.procname	= "disable_ipv6",
6540 		.data		= &ipv6_devconf.disable_ipv6,
6541 		.maxlen		= sizeof(int),
6542 		.mode		= 0644,
6543 		.proc_handler	= addrconf_sysctl_disable,
6544 	},
6545 	{
6546 		.procname	= "accept_dad",
6547 		.data		= &ipv6_devconf.accept_dad,
6548 		.maxlen		= sizeof(int),
6549 		.mode		= 0644,
6550 		.proc_handler	= proc_dointvec,
6551 	},
6552 	{
6553 		.procname	= "force_tllao",
6554 		.data		= &ipv6_devconf.force_tllao,
6555 		.maxlen		= sizeof(int),
6556 		.mode		= 0644,
6557 		.proc_handler	= proc_dointvec
6558 	},
6559 	{
6560 		.procname	= "ndisc_notify",
6561 		.data		= &ipv6_devconf.ndisc_notify,
6562 		.maxlen		= sizeof(int),
6563 		.mode		= 0644,
6564 		.proc_handler	= proc_dointvec
6565 	},
6566 	{
6567 		.procname	= "suppress_frag_ndisc",
6568 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6569 		.maxlen		= sizeof(int),
6570 		.mode		= 0644,
6571 		.proc_handler	= proc_dointvec
6572 	},
6573 	{
6574 		.procname	= "accept_ra_from_local",
6575 		.data		= &ipv6_devconf.accept_ra_from_local,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec,
6579 	},
6580 	{
6581 		.procname	= "accept_ra_mtu",
6582 		.data		= &ipv6_devconf.accept_ra_mtu,
6583 		.maxlen		= sizeof(int),
6584 		.mode		= 0644,
6585 		.proc_handler	= proc_dointvec,
6586 	},
6587 	{
6588 		.procname	= "stable_secret",
6589 		.data		= &ipv6_devconf.stable_secret,
6590 		.maxlen		= IPV6_MAX_STRLEN,
6591 		.mode		= 0600,
6592 		.proc_handler	= addrconf_sysctl_stable_secret,
6593 	},
6594 	{
6595 		.procname	= "use_oif_addrs_only",
6596 		.data		= &ipv6_devconf.use_oif_addrs_only,
6597 		.maxlen		= sizeof(int),
6598 		.mode		= 0644,
6599 		.proc_handler	= proc_dointvec,
6600 	},
6601 	{
6602 		.procname	= "ignore_routes_with_linkdown",
6603 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6604 		.maxlen		= sizeof(int),
6605 		.mode		= 0644,
6606 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6607 	},
6608 	{
6609 		.procname	= "drop_unicast_in_l2_multicast",
6610 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6611 		.maxlen		= sizeof(int),
6612 		.mode		= 0644,
6613 		.proc_handler	= proc_dointvec,
6614 	},
6615 	{
6616 		.procname	= "drop_unsolicited_na",
6617 		.data		= &ipv6_devconf.drop_unsolicited_na,
6618 		.maxlen		= sizeof(int),
6619 		.mode		= 0644,
6620 		.proc_handler	= proc_dointvec,
6621 	},
6622 	{
6623 		.procname	= "keep_addr_on_down",
6624 		.data		= &ipv6_devconf.keep_addr_on_down,
6625 		.maxlen		= sizeof(int),
6626 		.mode		= 0644,
6627 		.proc_handler	= proc_dointvec,
6628 
6629 	},
6630 	{
6631 		.procname	= "seg6_enabled",
6632 		.data		= &ipv6_devconf.seg6_enabled,
6633 		.maxlen		= sizeof(int),
6634 		.mode		= 0644,
6635 		.proc_handler	= proc_dointvec,
6636 	},
6637 #ifdef CONFIG_IPV6_SEG6_HMAC
6638 	{
6639 		.procname	= "seg6_require_hmac",
6640 		.data		= &ipv6_devconf.seg6_require_hmac,
6641 		.maxlen		= sizeof(int),
6642 		.mode		= 0644,
6643 		.proc_handler	= proc_dointvec,
6644 	},
6645 #endif
6646 	{
6647 		.procname       = "enhanced_dad",
6648 		.data           = &ipv6_devconf.enhanced_dad,
6649 		.maxlen         = sizeof(int),
6650 		.mode           = 0644,
6651 		.proc_handler   = proc_dointvec,
6652 	},
6653 	{
6654 		.procname		= "addr_gen_mode",
6655 		.data			= &ipv6_devconf.addr_gen_mode,
6656 		.maxlen			= sizeof(int),
6657 		.mode			= 0644,
6658 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6659 	},
6660 	{
6661 		.procname       = "disable_policy",
6662 		.data           = &ipv6_devconf.disable_policy,
6663 		.maxlen         = sizeof(int),
6664 		.mode           = 0644,
6665 		.proc_handler   = addrconf_sysctl_disable_policy,
6666 	},
6667 	{
6668 		.procname	= "ndisc_tclass",
6669 		.data		= &ipv6_devconf.ndisc_tclass,
6670 		.maxlen		= sizeof(int),
6671 		.mode		= 0644,
6672 		.proc_handler	= proc_dointvec_minmax,
6673 		.extra1		= (void *)&zero,
6674 		.extra2		= (void *)&two_five_five,
6675 	},
6676 	{
6677 		/* sentinel */
6678 	}
6679 };
6680 
6681 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6682 		struct inet6_dev *idev, struct ipv6_devconf *p)
6683 {
6684 	int i, ifindex;
6685 	struct ctl_table *table;
6686 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6687 
6688 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6689 	if (!table)
6690 		goto out;
6691 
6692 	for (i = 0; table[i].data; i++) {
6693 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6694 		/* If one of these is already set, then it is not safe to
6695 		 * overwrite either of them: this makes proc_dointvec_minmax
6696 		 * usable.
6697 		 */
6698 		if (!table[i].extra1 && !table[i].extra2) {
6699 			table[i].extra1 = idev; /* embedded; no ref */
6700 			table[i].extra2 = net;
6701 		}
6702 	}
6703 
6704 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6705 
6706 	p->sysctl_header = register_net_sysctl(net, path, table);
6707 	if (!p->sysctl_header)
6708 		goto free;
6709 
6710 	if (!strcmp(dev_name, "all"))
6711 		ifindex = NETCONFA_IFINDEX_ALL;
6712 	else if (!strcmp(dev_name, "default"))
6713 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6714 	else
6715 		ifindex = idev->dev->ifindex;
6716 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6717 				     ifindex, p);
6718 	return 0;
6719 
6720 free:
6721 	kfree(table);
6722 out:
6723 	return -ENOBUFS;
6724 }
6725 
6726 static void __addrconf_sysctl_unregister(struct net *net,
6727 					 struct ipv6_devconf *p, int ifindex)
6728 {
6729 	struct ctl_table *table;
6730 
6731 	if (!p->sysctl_header)
6732 		return;
6733 
6734 	table = p->sysctl_header->ctl_table_arg;
6735 	unregister_net_sysctl_table(p->sysctl_header);
6736 	p->sysctl_header = NULL;
6737 	kfree(table);
6738 
6739 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6740 }
6741 
6742 static int addrconf_sysctl_register(struct inet6_dev *idev)
6743 {
6744 	int err;
6745 
6746 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6747 		return -EINVAL;
6748 
6749 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6750 				    &ndisc_ifinfo_sysctl_change);
6751 	if (err)
6752 		return err;
6753 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6754 					 idev, &idev->cnf);
6755 	if (err)
6756 		neigh_sysctl_unregister(idev->nd_parms);
6757 
6758 	return err;
6759 }
6760 
6761 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6762 {
6763 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6764 				     idev->dev->ifindex);
6765 	neigh_sysctl_unregister(idev->nd_parms);
6766 }
6767 
6768 
6769 #endif
6770 
6771 static int __net_init addrconf_init_net(struct net *net)
6772 {
6773 	int err = -ENOMEM;
6774 	struct ipv6_devconf *all, *dflt;
6775 
6776 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6777 	if (!all)
6778 		goto err_alloc_all;
6779 
6780 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6781 	if (!dflt)
6782 		goto err_alloc_dflt;
6783 
6784 	/* these will be inherited by all namespaces */
6785 	dflt->autoconf = ipv6_defaults.autoconf;
6786 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6787 
6788 	dflt->stable_secret.initialized = false;
6789 	all->stable_secret.initialized = false;
6790 
6791 	net->ipv6.devconf_all = all;
6792 	net->ipv6.devconf_dflt = dflt;
6793 
6794 #ifdef CONFIG_SYSCTL
6795 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6796 	if (err < 0)
6797 		goto err_reg_all;
6798 
6799 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6800 	if (err < 0)
6801 		goto err_reg_dflt;
6802 #endif
6803 	return 0;
6804 
6805 #ifdef CONFIG_SYSCTL
6806 err_reg_dflt:
6807 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6808 err_reg_all:
6809 	kfree(dflt);
6810 #endif
6811 err_alloc_dflt:
6812 	kfree(all);
6813 err_alloc_all:
6814 	return err;
6815 }
6816 
6817 static void __net_exit addrconf_exit_net(struct net *net)
6818 {
6819 #ifdef CONFIG_SYSCTL
6820 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6821 				     NETCONFA_IFINDEX_DEFAULT);
6822 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6823 				     NETCONFA_IFINDEX_ALL);
6824 #endif
6825 	kfree(net->ipv6.devconf_dflt);
6826 	kfree(net->ipv6.devconf_all);
6827 }
6828 
6829 static struct pernet_operations addrconf_ops = {
6830 	.init = addrconf_init_net,
6831 	.exit = addrconf_exit_net,
6832 };
6833 
6834 static struct rtnl_af_ops inet6_ops __read_mostly = {
6835 	.family		  = AF_INET6,
6836 	.fill_link_af	  = inet6_fill_link_af,
6837 	.get_link_af_size = inet6_get_link_af_size,
6838 	.validate_link_af = inet6_validate_link_af,
6839 	.set_link_af	  = inet6_set_link_af,
6840 };
6841 
6842 /*
6843  *	Init / cleanup code
6844  */
6845 
6846 int __init addrconf_init(void)
6847 {
6848 	struct inet6_dev *idev;
6849 	int i, err;
6850 
6851 	err = ipv6_addr_label_init();
6852 	if (err < 0) {
6853 		pr_crit("%s: cannot initialize default policy table: %d\n",
6854 			__func__, err);
6855 		goto out;
6856 	}
6857 
6858 	err = register_pernet_subsys(&addrconf_ops);
6859 	if (err < 0)
6860 		goto out_addrlabel;
6861 
6862 	addrconf_wq = create_workqueue("ipv6_addrconf");
6863 	if (!addrconf_wq) {
6864 		err = -ENOMEM;
6865 		goto out_nowq;
6866 	}
6867 
6868 	/* The addrconf netdev notifier requires that loopback_dev
6869 	 * has it's ipv6 private information allocated and setup
6870 	 * before it can bring up and give link-local addresses
6871 	 * to other devices which are up.
6872 	 *
6873 	 * Unfortunately, loopback_dev is not necessarily the first
6874 	 * entry in the global dev_base list of net devices.  In fact,
6875 	 * it is likely to be the very last entry on that list.
6876 	 * So this causes the notifier registry below to try and
6877 	 * give link-local addresses to all devices besides loopback_dev
6878 	 * first, then loopback_dev, which cases all the non-loopback_dev
6879 	 * devices to fail to get a link-local address.
6880 	 *
6881 	 * So, as a temporary fix, allocate the ipv6 structure for
6882 	 * loopback_dev first by hand.
6883 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6884 	 * device and it being up should be removed.
6885 	 */
6886 	rtnl_lock();
6887 	idev = ipv6_add_dev(init_net.loopback_dev);
6888 	rtnl_unlock();
6889 	if (IS_ERR(idev)) {
6890 		err = PTR_ERR(idev);
6891 		goto errlo;
6892 	}
6893 
6894 	ip6_route_init_special_entries();
6895 
6896 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6897 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6898 
6899 	register_netdevice_notifier(&ipv6_dev_notf);
6900 
6901 	addrconf_verify();
6902 
6903 	rtnl_af_register(&inet6_ops);
6904 
6905 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
6906 				   NULL, inet6_dump_ifinfo, 0);
6907 	if (err < 0)
6908 		goto errout;
6909 
6910 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
6911 				   inet6_rtm_newaddr, NULL, 0);
6912 	if (err < 0)
6913 		goto errout;
6914 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
6915 				   inet6_rtm_deladdr, NULL, 0);
6916 	if (err < 0)
6917 		goto errout;
6918 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
6919 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
6920 				   RTNL_FLAG_DOIT_UNLOCKED);
6921 	if (err < 0)
6922 		goto errout;
6923 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
6924 				   NULL, inet6_dump_ifmcaddr, 0);
6925 	if (err < 0)
6926 		goto errout;
6927 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
6928 				   NULL, inet6_dump_ifacaddr, 0);
6929 	if (err < 0)
6930 		goto errout;
6931 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
6932 				   inet6_netconf_get_devconf,
6933 				   inet6_netconf_dump_devconf,
6934 				   RTNL_FLAG_DOIT_UNLOCKED);
6935 	if (err < 0)
6936 		goto errout;
6937 	err = ipv6_addr_label_rtnl_register();
6938 	if (err < 0)
6939 		goto errout;
6940 
6941 	return 0;
6942 errout:
6943 	rtnl_unregister_all(PF_INET6);
6944 	rtnl_af_unregister(&inet6_ops);
6945 	unregister_netdevice_notifier(&ipv6_dev_notf);
6946 errlo:
6947 	destroy_workqueue(addrconf_wq);
6948 out_nowq:
6949 	unregister_pernet_subsys(&addrconf_ops);
6950 out_addrlabel:
6951 	ipv6_addr_label_cleanup();
6952 out:
6953 	return err;
6954 }
6955 
6956 void addrconf_cleanup(void)
6957 {
6958 	struct net_device *dev;
6959 	int i;
6960 
6961 	unregister_netdevice_notifier(&ipv6_dev_notf);
6962 	unregister_pernet_subsys(&addrconf_ops);
6963 	ipv6_addr_label_cleanup();
6964 
6965 	rtnl_af_unregister(&inet6_ops);
6966 
6967 	rtnl_lock();
6968 
6969 	/* clean dev list */
6970 	for_each_netdev(&init_net, dev) {
6971 		if (__in6_dev_get(dev) == NULL)
6972 			continue;
6973 		addrconf_ifdown(dev, 1);
6974 	}
6975 	addrconf_ifdown(init_net.loopback_dev, 2);
6976 
6977 	/*
6978 	 *	Check hash table.
6979 	 */
6980 	spin_lock_bh(&addrconf_hash_lock);
6981 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6982 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6983 	spin_unlock_bh(&addrconf_hash_lock);
6984 	cancel_delayed_work(&addr_chk_work);
6985 	rtnl_unlock();
6986 
6987 	destroy_workqueue(addrconf_wq);
6988 }
6989