xref: /openbmc/linux/net/ipv6/addrconf.c (revision e368cd72)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 #include <linux/ioam6.h>
93 
94 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
95 
96 #define IPV6_MAX_STRLEN \
97 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
98 
99 static inline u32 cstamp_delta(unsigned long cstamp)
100 {
101 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
102 }
103 
104 static inline s32 rfc3315_s14_backoff_init(s32 irt)
105 {
106 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
107 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
108 	do_div(tmp, 1000000);
109 	return (s32)tmp;
110 }
111 
112 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
113 {
114 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
115 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
116 	do_div(tmp, 1000000);
117 	if ((s32)tmp > mrt) {
118 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
119 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
120 		do_div(tmp, 1000000);
121 	}
122 	return (s32)tmp;
123 }
124 
125 #ifdef CONFIG_SYSCTL
126 static int addrconf_sysctl_register(struct inet6_dev *idev);
127 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
128 #else
129 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
130 {
131 	return 0;
132 }
133 
134 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
135 {
136 }
137 #endif
138 
139 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 /*
150  *	Configured unicast address hash table
151  */
152 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
153 static DEFINE_SPINLOCK(addrconf_hash_lock);
154 
155 static void addrconf_verify(void);
156 static void addrconf_verify_rtnl(void);
157 static void addrconf_verify_work(struct work_struct *);
158 
159 static struct workqueue_struct *addrconf_wq;
160 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
161 
162 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
163 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
164 
165 static void addrconf_type_change(struct net_device *dev,
166 				 unsigned long event);
167 static int addrconf_ifdown(struct net_device *dev, bool unregister);
168 
169 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
170 						  int plen,
171 						  const struct net_device *dev,
172 						  u32 flags, u32 noflags,
173 						  bool no_gw);
174 
175 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
176 static void addrconf_dad_work(struct work_struct *w);
177 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
178 				   bool send_na);
179 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
180 static void addrconf_rs_timer(struct timer_list *t);
181 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
183 
184 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
185 				struct prefix_info *pinfo);
186 
187 static struct ipv6_devconf ipv6_devconf __read_mostly = {
188 	.forwarding		= 0,
189 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
190 	.mtu6			= IPV6_MIN_MTU,
191 	.accept_ra		= 1,
192 	.accept_redirects	= 1,
193 	.autoconf		= 1,
194 	.force_mld_version	= 0,
195 	.mldv1_unsolicited_report_interval = 10 * HZ,
196 	.mldv2_unsolicited_report_interval = HZ,
197 	.dad_transmits		= 1,
198 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
199 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
200 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
201 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
202 	.use_tempaddr		= 0,
203 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
204 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
205 	.regen_max_retry	= REGEN_MAX_RETRY,
206 	.max_desync_factor	= MAX_DESYNC_FACTOR,
207 	.max_addresses		= IPV6_MAX_ADDRESSES,
208 	.accept_ra_defrtr	= 1,
209 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
210 	.accept_ra_from_local	= 0,
211 	.accept_ra_min_hop_limit= 1,
212 	.accept_ra_pinfo	= 1,
213 #ifdef CONFIG_IPV6_ROUTER_PREF
214 	.accept_ra_rtr_pref	= 1,
215 	.rtr_probe_interval	= 60 * HZ,
216 #ifdef CONFIG_IPV6_ROUTE_INFO
217 	.accept_ra_rt_info_min_plen = 0,
218 	.accept_ra_rt_info_max_plen = 0,
219 #endif
220 #endif
221 	.proxy_ndp		= 0,
222 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
223 	.disable_ipv6		= 0,
224 	.accept_dad		= 0,
225 	.suppress_frag_ndisc	= 1,
226 	.accept_ra_mtu		= 1,
227 	.stable_secret		= {
228 		.initialized = false,
229 	},
230 	.use_oif_addrs_only	= 0,
231 	.ignore_routes_with_linkdown = 0,
232 	.keep_addr_on_down	= 0,
233 	.seg6_enabled		= 0,
234 #ifdef CONFIG_IPV6_SEG6_HMAC
235 	.seg6_require_hmac	= 0,
236 #endif
237 	.enhanced_dad           = 1,
238 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
239 	.disable_policy		= 0,
240 	.rpl_seg_enabled	= 0,
241 	.ioam6_enabled		= 0,
242 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
243 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
244 };
245 
246 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
247 	.forwarding		= 0,
248 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
249 	.mtu6			= IPV6_MIN_MTU,
250 	.accept_ra		= 1,
251 	.accept_redirects	= 1,
252 	.autoconf		= 1,
253 	.force_mld_version	= 0,
254 	.mldv1_unsolicited_report_interval = 10 * HZ,
255 	.mldv2_unsolicited_report_interval = HZ,
256 	.dad_transmits		= 1,
257 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
258 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
259 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
260 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
261 	.use_tempaddr		= 0,
262 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
263 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
264 	.regen_max_retry	= REGEN_MAX_RETRY,
265 	.max_desync_factor	= MAX_DESYNC_FACTOR,
266 	.max_addresses		= IPV6_MAX_ADDRESSES,
267 	.accept_ra_defrtr	= 1,
268 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
269 	.accept_ra_from_local	= 0,
270 	.accept_ra_min_hop_limit= 1,
271 	.accept_ra_pinfo	= 1,
272 #ifdef CONFIG_IPV6_ROUTER_PREF
273 	.accept_ra_rtr_pref	= 1,
274 	.rtr_probe_interval	= 60 * HZ,
275 #ifdef CONFIG_IPV6_ROUTE_INFO
276 	.accept_ra_rt_info_min_plen = 0,
277 	.accept_ra_rt_info_max_plen = 0,
278 #endif
279 #endif
280 	.proxy_ndp		= 0,
281 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
282 	.disable_ipv6		= 0,
283 	.accept_dad		= 1,
284 	.suppress_frag_ndisc	= 1,
285 	.accept_ra_mtu		= 1,
286 	.stable_secret		= {
287 		.initialized = false,
288 	},
289 	.use_oif_addrs_only	= 0,
290 	.ignore_routes_with_linkdown = 0,
291 	.keep_addr_on_down	= 0,
292 	.seg6_enabled		= 0,
293 #ifdef CONFIG_IPV6_SEG6_HMAC
294 	.seg6_require_hmac	= 0,
295 #endif
296 	.enhanced_dad           = 1,
297 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
298 	.disable_policy		= 0,
299 	.rpl_seg_enabled	= 0,
300 	.ioam6_enabled		= 0,
301 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
302 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
303 };
304 
305 /* Check if link is ready: is it up and is a valid qdisc available */
306 static inline bool addrconf_link_ready(const struct net_device *dev)
307 {
308 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
309 }
310 
311 static void addrconf_del_rs_timer(struct inet6_dev *idev)
312 {
313 	if (del_timer(&idev->rs_timer))
314 		__in6_dev_put(idev);
315 }
316 
317 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
318 {
319 	if (cancel_delayed_work(&ifp->dad_work))
320 		__in6_ifa_put(ifp);
321 }
322 
323 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
324 				  unsigned long when)
325 {
326 	if (!timer_pending(&idev->rs_timer))
327 		in6_dev_hold(idev);
328 	mod_timer(&idev->rs_timer, jiffies + when);
329 }
330 
331 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
332 				   unsigned long delay)
333 {
334 	in6_ifa_hold(ifp);
335 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
336 		in6_ifa_put(ifp);
337 }
338 
339 static int snmp6_alloc_dev(struct inet6_dev *idev)
340 {
341 	int i;
342 
343 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
344 	if (!idev->stats.ipv6)
345 		goto err_ip;
346 
347 	for_each_possible_cpu(i) {
348 		struct ipstats_mib *addrconf_stats;
349 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
350 		u64_stats_init(&addrconf_stats->syncp);
351 	}
352 
353 
354 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
355 					GFP_KERNEL);
356 	if (!idev->stats.icmpv6dev)
357 		goto err_icmp;
358 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
359 					   GFP_KERNEL);
360 	if (!idev->stats.icmpv6msgdev)
361 		goto err_icmpmsg;
362 
363 	return 0;
364 
365 err_icmpmsg:
366 	kfree(idev->stats.icmpv6dev);
367 err_icmp:
368 	free_percpu(idev->stats.ipv6);
369 err_ip:
370 	return -ENOMEM;
371 }
372 
373 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
374 {
375 	struct inet6_dev *ndev;
376 	int err = -ENOMEM;
377 
378 	ASSERT_RTNL();
379 
380 	if (dev->mtu < IPV6_MIN_MTU)
381 		return ERR_PTR(-EINVAL);
382 
383 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
384 	if (!ndev)
385 		return ERR_PTR(err);
386 
387 	rwlock_init(&ndev->lock);
388 	ndev->dev = dev;
389 	INIT_LIST_HEAD(&ndev->addr_list);
390 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
391 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
392 
393 	if (ndev->cnf.stable_secret.initialized)
394 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
395 
396 	ndev->cnf.mtu6 = dev->mtu;
397 	ndev->ra_mtu = 0;
398 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
399 	if (!ndev->nd_parms) {
400 		kfree(ndev);
401 		return ERR_PTR(err);
402 	}
403 	if (ndev->cnf.forwarding)
404 		dev_disable_lro(dev);
405 	/* We refer to the device */
406 	dev_hold(dev);
407 
408 	if (snmp6_alloc_dev(ndev) < 0) {
409 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
410 			   __func__);
411 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
412 		dev_put(dev);
413 		kfree(ndev);
414 		return ERR_PTR(err);
415 	}
416 
417 	if (snmp6_register_dev(ndev) < 0) {
418 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
419 			   __func__, dev->name);
420 		goto err_release;
421 	}
422 
423 	/* One reference from device. */
424 	refcount_set(&ndev->refcnt, 1);
425 
426 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
427 		ndev->cnf.accept_dad = -1;
428 
429 #if IS_ENABLED(CONFIG_IPV6_SIT)
430 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
431 		pr_info("%s: Disabled Multicast RS\n", dev->name);
432 		ndev->cnf.rtr_solicits = 0;
433 	}
434 #endif
435 
436 	INIT_LIST_HEAD(&ndev->tempaddr_list);
437 	ndev->desync_factor = U32_MAX;
438 	if ((dev->flags&IFF_LOOPBACK) ||
439 	    dev->type == ARPHRD_TUNNEL ||
440 	    dev->type == ARPHRD_TUNNEL6 ||
441 	    dev->type == ARPHRD_SIT ||
442 	    dev->type == ARPHRD_NONE) {
443 		ndev->cnf.use_tempaddr = -1;
444 	}
445 
446 	ndev->token = in6addr_any;
447 
448 	if (netif_running(dev) && addrconf_link_ready(dev))
449 		ndev->if_flags |= IF_READY;
450 
451 	ipv6_mc_init_dev(ndev);
452 	ndev->tstamp = jiffies;
453 	err = addrconf_sysctl_register(ndev);
454 	if (err) {
455 		ipv6_mc_destroy_dev(ndev);
456 		snmp6_unregister_dev(ndev);
457 		goto err_release;
458 	}
459 	/* protected by rtnl_lock */
460 	rcu_assign_pointer(dev->ip6_ptr, ndev);
461 
462 	/* Join interface-local all-node multicast group */
463 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
464 
465 	/* Join all-node multicast group */
466 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
467 
468 	/* Join all-router multicast group if forwarding is set */
469 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
470 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
471 
472 	return ndev;
473 
474 err_release:
475 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
476 	ndev->dead = 1;
477 	in6_dev_finish_destroy(ndev);
478 	return ERR_PTR(err);
479 }
480 
481 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
482 {
483 	struct inet6_dev *idev;
484 
485 	ASSERT_RTNL();
486 
487 	idev = __in6_dev_get(dev);
488 	if (!idev) {
489 		idev = ipv6_add_dev(dev);
490 		if (IS_ERR(idev))
491 			return idev;
492 	}
493 
494 	if (dev->flags&IFF_UP)
495 		ipv6_mc_up(idev);
496 	return idev;
497 }
498 
499 static int inet6_netconf_msgsize_devconf(int type)
500 {
501 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
502 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
503 	bool all = false;
504 
505 	if (type == NETCONFA_ALL)
506 		all = true;
507 
508 	if (all || type == NETCONFA_FORWARDING)
509 		size += nla_total_size(4);
510 #ifdef CONFIG_IPV6_MROUTE
511 	if (all || type == NETCONFA_MC_FORWARDING)
512 		size += nla_total_size(4);
513 #endif
514 	if (all || type == NETCONFA_PROXY_NEIGH)
515 		size += nla_total_size(4);
516 
517 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
518 		size += nla_total_size(4);
519 
520 	return size;
521 }
522 
523 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
524 				      struct ipv6_devconf *devconf, u32 portid,
525 				      u32 seq, int event, unsigned int flags,
526 				      int type)
527 {
528 	struct nlmsghdr  *nlh;
529 	struct netconfmsg *ncm;
530 	bool all = false;
531 
532 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
533 			flags);
534 	if (!nlh)
535 		return -EMSGSIZE;
536 
537 	if (type == NETCONFA_ALL)
538 		all = true;
539 
540 	ncm = nlmsg_data(nlh);
541 	ncm->ncm_family = AF_INET6;
542 
543 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
544 		goto nla_put_failure;
545 
546 	if (!devconf)
547 		goto out;
548 
549 	if ((all || type == NETCONFA_FORWARDING) &&
550 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
551 		goto nla_put_failure;
552 #ifdef CONFIG_IPV6_MROUTE
553 	if ((all || type == NETCONFA_MC_FORWARDING) &&
554 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
555 			devconf->mc_forwarding) < 0)
556 		goto nla_put_failure;
557 #endif
558 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
559 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
560 		goto nla_put_failure;
561 
562 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
563 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
564 			devconf->ignore_routes_with_linkdown) < 0)
565 		goto nla_put_failure;
566 
567 out:
568 	nlmsg_end(skb, nlh);
569 	return 0;
570 
571 nla_put_failure:
572 	nlmsg_cancel(skb, nlh);
573 	return -EMSGSIZE;
574 }
575 
576 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
577 				  int ifindex, struct ipv6_devconf *devconf)
578 {
579 	struct sk_buff *skb;
580 	int err = -ENOBUFS;
581 
582 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
583 	if (!skb)
584 		goto errout;
585 
586 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
587 					 event, 0, type);
588 	if (err < 0) {
589 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
590 		WARN_ON(err == -EMSGSIZE);
591 		kfree_skb(skb);
592 		goto errout;
593 	}
594 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
595 	return;
596 errout:
597 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
598 }
599 
600 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
601 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
602 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
603 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
604 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
605 };
606 
607 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
608 				       const struct nlmsghdr *nlh,
609 				       struct nlattr **tb,
610 				       struct netlink_ext_ack *extack)
611 {
612 	int i, err;
613 
614 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
615 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
616 		return -EINVAL;
617 	}
618 
619 	if (!netlink_strict_get_check(skb))
620 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
621 					      tb, NETCONFA_MAX,
622 					      devconf_ipv6_policy, extack);
623 
624 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
625 					    tb, NETCONFA_MAX,
626 					    devconf_ipv6_policy, extack);
627 	if (err)
628 		return err;
629 
630 	for (i = 0; i <= NETCONFA_MAX; i++) {
631 		if (!tb[i])
632 			continue;
633 
634 		switch (i) {
635 		case NETCONFA_IFINDEX:
636 			break;
637 		default:
638 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
639 			return -EINVAL;
640 		}
641 	}
642 
643 	return 0;
644 }
645 
646 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
647 				     struct nlmsghdr *nlh,
648 				     struct netlink_ext_ack *extack)
649 {
650 	struct net *net = sock_net(in_skb->sk);
651 	struct nlattr *tb[NETCONFA_MAX+1];
652 	struct inet6_dev *in6_dev = NULL;
653 	struct net_device *dev = NULL;
654 	struct sk_buff *skb;
655 	struct ipv6_devconf *devconf;
656 	int ifindex;
657 	int err;
658 
659 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
660 	if (err < 0)
661 		return err;
662 
663 	if (!tb[NETCONFA_IFINDEX])
664 		return -EINVAL;
665 
666 	err = -EINVAL;
667 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
668 	switch (ifindex) {
669 	case NETCONFA_IFINDEX_ALL:
670 		devconf = net->ipv6.devconf_all;
671 		break;
672 	case NETCONFA_IFINDEX_DEFAULT:
673 		devconf = net->ipv6.devconf_dflt;
674 		break;
675 	default:
676 		dev = dev_get_by_index(net, ifindex);
677 		if (!dev)
678 			return -EINVAL;
679 		in6_dev = in6_dev_get(dev);
680 		if (!in6_dev)
681 			goto errout;
682 		devconf = &in6_dev->cnf;
683 		break;
684 	}
685 
686 	err = -ENOBUFS;
687 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
688 	if (!skb)
689 		goto errout;
690 
691 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
692 					 NETLINK_CB(in_skb).portid,
693 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
694 					 NETCONFA_ALL);
695 	if (err < 0) {
696 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
697 		WARN_ON(err == -EMSGSIZE);
698 		kfree_skb(skb);
699 		goto errout;
700 	}
701 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
702 errout:
703 	if (in6_dev)
704 		in6_dev_put(in6_dev);
705 	dev_put(dev);
706 	return err;
707 }
708 
709 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
710 				      struct netlink_callback *cb)
711 {
712 	const struct nlmsghdr *nlh = cb->nlh;
713 	struct net *net = sock_net(skb->sk);
714 	int h, s_h;
715 	int idx, s_idx;
716 	struct net_device *dev;
717 	struct inet6_dev *idev;
718 	struct hlist_head *head;
719 
720 	if (cb->strict_check) {
721 		struct netlink_ext_ack *extack = cb->extack;
722 		struct netconfmsg *ncm;
723 
724 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
725 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
726 			return -EINVAL;
727 		}
728 
729 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
730 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
731 			return -EINVAL;
732 		}
733 	}
734 
735 	s_h = cb->args[0];
736 	s_idx = idx = cb->args[1];
737 
738 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
739 		idx = 0;
740 		head = &net->dev_index_head[h];
741 		rcu_read_lock();
742 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
743 			  net->dev_base_seq;
744 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
745 			if (idx < s_idx)
746 				goto cont;
747 			idev = __in6_dev_get(dev);
748 			if (!idev)
749 				goto cont;
750 
751 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
752 						       &idev->cnf,
753 						       NETLINK_CB(cb->skb).portid,
754 						       nlh->nlmsg_seq,
755 						       RTM_NEWNETCONF,
756 						       NLM_F_MULTI,
757 						       NETCONFA_ALL) < 0) {
758 				rcu_read_unlock();
759 				goto done;
760 			}
761 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
762 cont:
763 			idx++;
764 		}
765 		rcu_read_unlock();
766 	}
767 	if (h == NETDEV_HASHENTRIES) {
768 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
769 					       net->ipv6.devconf_all,
770 					       NETLINK_CB(cb->skb).portid,
771 					       nlh->nlmsg_seq,
772 					       RTM_NEWNETCONF, NLM_F_MULTI,
773 					       NETCONFA_ALL) < 0)
774 			goto done;
775 		else
776 			h++;
777 	}
778 	if (h == NETDEV_HASHENTRIES + 1) {
779 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
780 					       net->ipv6.devconf_dflt,
781 					       NETLINK_CB(cb->skb).portid,
782 					       nlh->nlmsg_seq,
783 					       RTM_NEWNETCONF, NLM_F_MULTI,
784 					       NETCONFA_ALL) < 0)
785 			goto done;
786 		else
787 			h++;
788 	}
789 done:
790 	cb->args[0] = h;
791 	cb->args[1] = idx;
792 
793 	return skb->len;
794 }
795 
796 #ifdef CONFIG_SYSCTL
797 static void dev_forward_change(struct inet6_dev *idev)
798 {
799 	struct net_device *dev;
800 	struct inet6_ifaddr *ifa;
801 
802 	if (!idev)
803 		return;
804 	dev = idev->dev;
805 	if (idev->cnf.forwarding)
806 		dev_disable_lro(dev);
807 	if (dev->flags & IFF_MULTICAST) {
808 		if (idev->cnf.forwarding) {
809 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
810 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
811 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
812 		} else {
813 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
814 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
815 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
816 		}
817 	}
818 
819 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
820 		if (ifa->flags&IFA_F_TENTATIVE)
821 			continue;
822 		if (idev->cnf.forwarding)
823 			addrconf_join_anycast(ifa);
824 		else
825 			addrconf_leave_anycast(ifa);
826 	}
827 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
828 				     NETCONFA_FORWARDING,
829 				     dev->ifindex, &idev->cnf);
830 }
831 
832 
833 static void addrconf_forward_change(struct net *net, __s32 newf)
834 {
835 	struct net_device *dev;
836 	struct inet6_dev *idev;
837 
838 	for_each_netdev(net, dev) {
839 		idev = __in6_dev_get(dev);
840 		if (idev) {
841 			int changed = (!idev->cnf.forwarding) ^ (!newf);
842 			idev->cnf.forwarding = newf;
843 			if (changed)
844 				dev_forward_change(idev);
845 		}
846 	}
847 }
848 
849 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
850 {
851 	struct net *net;
852 	int old;
853 
854 	if (!rtnl_trylock())
855 		return restart_syscall();
856 
857 	net = (struct net *)table->extra2;
858 	old = *p;
859 	*p = newf;
860 
861 	if (p == &net->ipv6.devconf_dflt->forwarding) {
862 		if ((!newf) ^ (!old))
863 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
864 						     NETCONFA_FORWARDING,
865 						     NETCONFA_IFINDEX_DEFAULT,
866 						     net->ipv6.devconf_dflt);
867 		rtnl_unlock();
868 		return 0;
869 	}
870 
871 	if (p == &net->ipv6.devconf_all->forwarding) {
872 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
873 
874 		net->ipv6.devconf_dflt->forwarding = newf;
875 		if ((!newf) ^ (!old_dflt))
876 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
877 						     NETCONFA_FORWARDING,
878 						     NETCONFA_IFINDEX_DEFAULT,
879 						     net->ipv6.devconf_dflt);
880 
881 		addrconf_forward_change(net, newf);
882 		if ((!newf) ^ (!old))
883 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
884 						     NETCONFA_FORWARDING,
885 						     NETCONFA_IFINDEX_ALL,
886 						     net->ipv6.devconf_all);
887 	} else if ((!newf) ^ (!old))
888 		dev_forward_change((struct inet6_dev *)table->extra1);
889 	rtnl_unlock();
890 
891 	if (newf)
892 		rt6_purge_dflt_routers(net);
893 	return 1;
894 }
895 
896 static void addrconf_linkdown_change(struct net *net, __s32 newf)
897 {
898 	struct net_device *dev;
899 	struct inet6_dev *idev;
900 
901 	for_each_netdev(net, dev) {
902 		idev = __in6_dev_get(dev);
903 		if (idev) {
904 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
905 
906 			idev->cnf.ignore_routes_with_linkdown = newf;
907 			if (changed)
908 				inet6_netconf_notify_devconf(dev_net(dev),
909 							     RTM_NEWNETCONF,
910 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
911 							     dev->ifindex,
912 							     &idev->cnf);
913 		}
914 	}
915 }
916 
917 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
918 {
919 	struct net *net;
920 	int old;
921 
922 	if (!rtnl_trylock())
923 		return restart_syscall();
924 
925 	net = (struct net *)table->extra2;
926 	old = *p;
927 	*p = newf;
928 
929 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
930 		if ((!newf) ^ (!old))
931 			inet6_netconf_notify_devconf(net,
932 						     RTM_NEWNETCONF,
933 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
934 						     NETCONFA_IFINDEX_DEFAULT,
935 						     net->ipv6.devconf_dflt);
936 		rtnl_unlock();
937 		return 0;
938 	}
939 
940 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
941 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
942 		addrconf_linkdown_change(net, newf);
943 		if ((!newf) ^ (!old))
944 			inet6_netconf_notify_devconf(net,
945 						     RTM_NEWNETCONF,
946 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
947 						     NETCONFA_IFINDEX_ALL,
948 						     net->ipv6.devconf_all);
949 	}
950 	rtnl_unlock();
951 
952 	return 1;
953 }
954 
955 #endif
956 
957 /* Nobody refers to this ifaddr, destroy it */
958 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
959 {
960 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
961 
962 #ifdef NET_REFCNT_DEBUG
963 	pr_debug("%s\n", __func__);
964 #endif
965 
966 	in6_dev_put(ifp->idev);
967 
968 	if (cancel_delayed_work(&ifp->dad_work))
969 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
970 			  ifp);
971 
972 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
973 		pr_warn("Freeing alive inet6 address %p\n", ifp);
974 		return;
975 	}
976 
977 	kfree_rcu(ifp, rcu);
978 }
979 
980 static void
981 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
982 {
983 	struct list_head *p;
984 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
985 
986 	/*
987 	 * Each device address list is sorted in order of scope -
988 	 * global before linklocal.
989 	 */
990 	list_for_each(p, &idev->addr_list) {
991 		struct inet6_ifaddr *ifa
992 			= list_entry(p, struct inet6_ifaddr, if_list);
993 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
994 			break;
995 	}
996 
997 	list_add_tail_rcu(&ifp->if_list, p);
998 }
999 
1000 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1001 {
1002 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
1003 
1004 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1005 }
1006 
1007 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1008 			       struct net_device *dev, unsigned int hash)
1009 {
1010 	struct inet6_ifaddr *ifp;
1011 
1012 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1013 		if (!net_eq(dev_net(ifp->idev->dev), net))
1014 			continue;
1015 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1016 			if (!dev || ifp->idev->dev == dev)
1017 				return true;
1018 		}
1019 	}
1020 	return false;
1021 }
1022 
1023 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1024 {
1025 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1026 	int err = 0;
1027 
1028 	spin_lock(&addrconf_hash_lock);
1029 
1030 	/* Ignore adding duplicate addresses on an interface */
1031 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1032 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1033 		err = -EEXIST;
1034 	} else {
1035 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1036 	}
1037 
1038 	spin_unlock(&addrconf_hash_lock);
1039 
1040 	return err;
1041 }
1042 
1043 /* On success it returns ifp with increased reference count */
1044 
1045 static struct inet6_ifaddr *
1046 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1047 	      bool can_block, struct netlink_ext_ack *extack)
1048 {
1049 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1050 	int addr_type = ipv6_addr_type(cfg->pfx);
1051 	struct net *net = dev_net(idev->dev);
1052 	struct inet6_ifaddr *ifa = NULL;
1053 	struct fib6_info *f6i = NULL;
1054 	int err = 0;
1055 
1056 	if (addr_type == IPV6_ADDR_ANY ||
1057 	    (addr_type & IPV6_ADDR_MULTICAST &&
1058 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1059 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1060 	     !netif_is_l3_master(idev->dev) &&
1061 	     addr_type & IPV6_ADDR_LOOPBACK))
1062 		return ERR_PTR(-EADDRNOTAVAIL);
1063 
1064 	if (idev->dead) {
1065 		err = -ENODEV;			/*XXX*/
1066 		goto out;
1067 	}
1068 
1069 	if (idev->cnf.disable_ipv6) {
1070 		err = -EACCES;
1071 		goto out;
1072 	}
1073 
1074 	/* validator notifier needs to be blocking;
1075 	 * do not call in atomic context
1076 	 */
1077 	if (can_block) {
1078 		struct in6_validator_info i6vi = {
1079 			.i6vi_addr = *cfg->pfx,
1080 			.i6vi_dev = idev,
1081 			.extack = extack,
1082 		};
1083 
1084 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1085 		err = notifier_to_errno(err);
1086 		if (err < 0)
1087 			goto out;
1088 	}
1089 
1090 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1091 	if (!ifa) {
1092 		err = -ENOBUFS;
1093 		goto out;
1094 	}
1095 
1096 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1097 	if (IS_ERR(f6i)) {
1098 		err = PTR_ERR(f6i);
1099 		f6i = NULL;
1100 		goto out;
1101 	}
1102 
1103 	if (net->ipv6.devconf_all->disable_policy ||
1104 	    idev->cnf.disable_policy)
1105 		f6i->dst_nopolicy = true;
1106 
1107 	neigh_parms_data_state_setall(idev->nd_parms);
1108 
1109 	ifa->addr = *cfg->pfx;
1110 	if (cfg->peer_pfx)
1111 		ifa->peer_addr = *cfg->peer_pfx;
1112 
1113 	spin_lock_init(&ifa->lock);
1114 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1115 	INIT_HLIST_NODE(&ifa->addr_lst);
1116 	ifa->scope = cfg->scope;
1117 	ifa->prefix_len = cfg->plen;
1118 	ifa->rt_priority = cfg->rt_priority;
1119 	ifa->flags = cfg->ifa_flags;
1120 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1121 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1122 		ifa->flags |= IFA_F_TENTATIVE;
1123 	ifa->valid_lft = cfg->valid_lft;
1124 	ifa->prefered_lft = cfg->preferred_lft;
1125 	ifa->cstamp = ifa->tstamp = jiffies;
1126 	ifa->tokenized = false;
1127 
1128 	ifa->rt = f6i;
1129 
1130 	ifa->idev = idev;
1131 	in6_dev_hold(idev);
1132 
1133 	/* For caller */
1134 	refcount_set(&ifa->refcnt, 1);
1135 
1136 	rcu_read_lock_bh();
1137 
1138 	err = ipv6_add_addr_hash(idev->dev, ifa);
1139 	if (err < 0) {
1140 		rcu_read_unlock_bh();
1141 		goto out;
1142 	}
1143 
1144 	write_lock(&idev->lock);
1145 
1146 	/* Add to inet6_dev unicast addr list. */
1147 	ipv6_link_dev_addr(idev, ifa);
1148 
1149 	if (ifa->flags&IFA_F_TEMPORARY) {
1150 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1151 		in6_ifa_hold(ifa);
1152 	}
1153 
1154 	in6_ifa_hold(ifa);
1155 	write_unlock(&idev->lock);
1156 
1157 	rcu_read_unlock_bh();
1158 
1159 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1160 out:
1161 	if (unlikely(err < 0)) {
1162 		fib6_info_release(f6i);
1163 
1164 		if (ifa) {
1165 			if (ifa->idev)
1166 				in6_dev_put(ifa->idev);
1167 			kfree(ifa);
1168 		}
1169 		ifa = ERR_PTR(err);
1170 	}
1171 
1172 	return ifa;
1173 }
1174 
1175 enum cleanup_prefix_rt_t {
1176 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1177 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1178 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1179 };
1180 
1181 /*
1182  * Check, whether the prefix for ifp would still need a prefix route
1183  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1184  * constants.
1185  *
1186  * 1) we don't purge prefix if address was not permanent.
1187  *    prefix is managed by its own lifetime.
1188  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1189  * 3) if there are no addresses, delete prefix.
1190  * 4) if there are still other permanent address(es),
1191  *    corresponding prefix is still permanent.
1192  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1193  *    don't purge the prefix, assume user space is managing it.
1194  * 6) otherwise, update prefix lifetime to the
1195  *    longest valid lifetime among the corresponding
1196  *    addresses on the device.
1197  *    Note: subsequent RA will update lifetime.
1198  **/
1199 static enum cleanup_prefix_rt_t
1200 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1201 {
1202 	struct inet6_ifaddr *ifa;
1203 	struct inet6_dev *idev = ifp->idev;
1204 	unsigned long lifetime;
1205 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1206 
1207 	*expires = jiffies;
1208 
1209 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1210 		if (ifa == ifp)
1211 			continue;
1212 		if (ifa->prefix_len != ifp->prefix_len ||
1213 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1214 				       ifp->prefix_len))
1215 			continue;
1216 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1217 			return CLEANUP_PREFIX_RT_NOP;
1218 
1219 		action = CLEANUP_PREFIX_RT_EXPIRE;
1220 
1221 		spin_lock(&ifa->lock);
1222 
1223 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1224 		/*
1225 		 * Note: Because this address is
1226 		 * not permanent, lifetime <
1227 		 * LONG_MAX / HZ here.
1228 		 */
1229 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1230 			*expires = ifa->tstamp + lifetime * HZ;
1231 		spin_unlock(&ifa->lock);
1232 	}
1233 
1234 	return action;
1235 }
1236 
1237 static void
1238 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1239 		     bool del_rt, bool del_peer)
1240 {
1241 	struct fib6_info *f6i;
1242 
1243 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1244 					ifp->prefix_len,
1245 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1246 	if (f6i) {
1247 		if (del_rt)
1248 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1249 		else {
1250 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1251 				fib6_set_expires(f6i, expires);
1252 			fib6_info_release(f6i);
1253 		}
1254 	}
1255 }
1256 
1257 
1258 /* This function wants to get referenced ifp and releases it before return */
1259 
1260 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1261 {
1262 	int state;
1263 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1264 	unsigned long expires;
1265 
1266 	ASSERT_RTNL();
1267 
1268 	spin_lock_bh(&ifp->lock);
1269 	state = ifp->state;
1270 	ifp->state = INET6_IFADDR_STATE_DEAD;
1271 	spin_unlock_bh(&ifp->lock);
1272 
1273 	if (state == INET6_IFADDR_STATE_DEAD)
1274 		goto out;
1275 
1276 	spin_lock_bh(&addrconf_hash_lock);
1277 	hlist_del_init_rcu(&ifp->addr_lst);
1278 	spin_unlock_bh(&addrconf_hash_lock);
1279 
1280 	write_lock_bh(&ifp->idev->lock);
1281 
1282 	if (ifp->flags&IFA_F_TEMPORARY) {
1283 		list_del(&ifp->tmp_list);
1284 		if (ifp->ifpub) {
1285 			in6_ifa_put(ifp->ifpub);
1286 			ifp->ifpub = NULL;
1287 		}
1288 		__in6_ifa_put(ifp);
1289 	}
1290 
1291 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1292 		action = check_cleanup_prefix_route(ifp, &expires);
1293 
1294 	list_del_rcu(&ifp->if_list);
1295 	__in6_ifa_put(ifp);
1296 
1297 	write_unlock_bh(&ifp->idev->lock);
1298 
1299 	addrconf_del_dad_work(ifp);
1300 
1301 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1302 
1303 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1304 
1305 	if (action != CLEANUP_PREFIX_RT_NOP) {
1306 		cleanup_prefix_route(ifp, expires,
1307 			action == CLEANUP_PREFIX_RT_DEL, false);
1308 	}
1309 
1310 	/* clean up prefsrc entries */
1311 	rt6_remove_prefsrc(ifp);
1312 out:
1313 	in6_ifa_put(ifp);
1314 }
1315 
1316 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1317 {
1318 	struct inet6_dev *idev = ifp->idev;
1319 	unsigned long tmp_tstamp, age;
1320 	unsigned long regen_advance;
1321 	unsigned long now = jiffies;
1322 	s32 cnf_temp_preferred_lft;
1323 	struct inet6_ifaddr *ift;
1324 	struct ifa6_config cfg;
1325 	long max_desync_factor;
1326 	struct in6_addr addr;
1327 	int ret = 0;
1328 
1329 	write_lock_bh(&idev->lock);
1330 
1331 retry:
1332 	in6_dev_hold(idev);
1333 	if (idev->cnf.use_tempaddr <= 0) {
1334 		write_unlock_bh(&idev->lock);
1335 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1336 		in6_dev_put(idev);
1337 		ret = -1;
1338 		goto out;
1339 	}
1340 	spin_lock_bh(&ifp->lock);
1341 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1342 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1343 		spin_unlock_bh(&ifp->lock);
1344 		write_unlock_bh(&idev->lock);
1345 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1346 			__func__);
1347 		in6_dev_put(idev);
1348 		ret = -1;
1349 		goto out;
1350 	}
1351 	in6_ifa_hold(ifp);
1352 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1353 	ipv6_gen_rnd_iid(&addr);
1354 
1355 	age = (now - ifp->tstamp) / HZ;
1356 
1357 	regen_advance = idev->cnf.regen_max_retry *
1358 			idev->cnf.dad_transmits *
1359 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1360 
1361 	/* recalculate max_desync_factor each time and update
1362 	 * idev->desync_factor if it's larger
1363 	 */
1364 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1365 	max_desync_factor = min_t(__u32,
1366 				  idev->cnf.max_desync_factor,
1367 				  cnf_temp_preferred_lft - regen_advance);
1368 
1369 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1370 		if (max_desync_factor > 0) {
1371 			get_random_bytes(&idev->desync_factor,
1372 					 sizeof(idev->desync_factor));
1373 			idev->desync_factor %= max_desync_factor;
1374 		} else {
1375 			idev->desync_factor = 0;
1376 		}
1377 	}
1378 
1379 	memset(&cfg, 0, sizeof(cfg));
1380 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1381 			      idev->cnf.temp_valid_lft + age);
1382 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1383 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1384 
1385 	cfg.plen = ifp->prefix_len;
1386 	tmp_tstamp = ifp->tstamp;
1387 	spin_unlock_bh(&ifp->lock);
1388 
1389 	write_unlock_bh(&idev->lock);
1390 
1391 	/* A temporary address is created only if this calculated Preferred
1392 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1393 	 * an implementation must not create a temporary address with a zero
1394 	 * Preferred Lifetime.
1395 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1396 	 * temporary addresses being generated.
1397 	 */
1398 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1399 	if (cfg.preferred_lft <= regen_advance + age) {
1400 		in6_ifa_put(ifp);
1401 		in6_dev_put(idev);
1402 		ret = -1;
1403 		goto out;
1404 	}
1405 
1406 	cfg.ifa_flags = IFA_F_TEMPORARY;
1407 	/* set in addrconf_prefix_rcv() */
1408 	if (ifp->flags & IFA_F_OPTIMISTIC)
1409 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1410 
1411 	cfg.pfx = &addr;
1412 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1413 
1414 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1415 	if (IS_ERR(ift)) {
1416 		in6_ifa_put(ifp);
1417 		in6_dev_put(idev);
1418 		pr_info("%s: retry temporary address regeneration\n", __func__);
1419 		write_lock_bh(&idev->lock);
1420 		goto retry;
1421 	}
1422 
1423 	spin_lock_bh(&ift->lock);
1424 	ift->ifpub = ifp;
1425 	ift->cstamp = now;
1426 	ift->tstamp = tmp_tstamp;
1427 	spin_unlock_bh(&ift->lock);
1428 
1429 	addrconf_dad_start(ift);
1430 	in6_ifa_put(ift);
1431 	in6_dev_put(idev);
1432 out:
1433 	return ret;
1434 }
1435 
1436 /*
1437  *	Choose an appropriate source address (RFC3484)
1438  */
1439 enum {
1440 	IPV6_SADDR_RULE_INIT = 0,
1441 	IPV6_SADDR_RULE_LOCAL,
1442 	IPV6_SADDR_RULE_SCOPE,
1443 	IPV6_SADDR_RULE_PREFERRED,
1444 #ifdef CONFIG_IPV6_MIP6
1445 	IPV6_SADDR_RULE_HOA,
1446 #endif
1447 	IPV6_SADDR_RULE_OIF,
1448 	IPV6_SADDR_RULE_LABEL,
1449 	IPV6_SADDR_RULE_PRIVACY,
1450 	IPV6_SADDR_RULE_ORCHID,
1451 	IPV6_SADDR_RULE_PREFIX,
1452 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1453 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1454 #endif
1455 	IPV6_SADDR_RULE_MAX
1456 };
1457 
1458 struct ipv6_saddr_score {
1459 	int			rule;
1460 	int			addr_type;
1461 	struct inet6_ifaddr	*ifa;
1462 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1463 	int			scopedist;
1464 	int			matchlen;
1465 };
1466 
1467 struct ipv6_saddr_dst {
1468 	const struct in6_addr *addr;
1469 	int ifindex;
1470 	int scope;
1471 	int label;
1472 	unsigned int prefs;
1473 };
1474 
1475 static inline int ipv6_saddr_preferred(int type)
1476 {
1477 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1478 		return 1;
1479 	return 0;
1480 }
1481 
1482 static bool ipv6_use_optimistic_addr(struct net *net,
1483 				     struct inet6_dev *idev)
1484 {
1485 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1486 	if (!idev)
1487 		return false;
1488 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1489 		return false;
1490 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1491 		return false;
1492 
1493 	return true;
1494 #else
1495 	return false;
1496 #endif
1497 }
1498 
1499 static bool ipv6_allow_optimistic_dad(struct net *net,
1500 				      struct inet6_dev *idev)
1501 {
1502 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1503 	if (!idev)
1504 		return false;
1505 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1506 		return false;
1507 
1508 	return true;
1509 #else
1510 	return false;
1511 #endif
1512 }
1513 
1514 static int ipv6_get_saddr_eval(struct net *net,
1515 			       struct ipv6_saddr_score *score,
1516 			       struct ipv6_saddr_dst *dst,
1517 			       int i)
1518 {
1519 	int ret;
1520 
1521 	if (i <= score->rule) {
1522 		switch (i) {
1523 		case IPV6_SADDR_RULE_SCOPE:
1524 			ret = score->scopedist;
1525 			break;
1526 		case IPV6_SADDR_RULE_PREFIX:
1527 			ret = score->matchlen;
1528 			break;
1529 		default:
1530 			ret = !!test_bit(i, score->scorebits);
1531 		}
1532 		goto out;
1533 	}
1534 
1535 	switch (i) {
1536 	case IPV6_SADDR_RULE_INIT:
1537 		/* Rule 0: remember if hiscore is not ready yet */
1538 		ret = !!score->ifa;
1539 		break;
1540 	case IPV6_SADDR_RULE_LOCAL:
1541 		/* Rule 1: Prefer same address */
1542 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1543 		break;
1544 	case IPV6_SADDR_RULE_SCOPE:
1545 		/* Rule 2: Prefer appropriate scope
1546 		 *
1547 		 *      ret
1548 		 *       ^
1549 		 *    -1 |  d 15
1550 		 *    ---+--+-+---> scope
1551 		 *       |
1552 		 *       |             d is scope of the destination.
1553 		 *  B-d  |  \
1554 		 *       |   \      <- smaller scope is better if
1555 		 *  B-15 |    \        if scope is enough for destination.
1556 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1557 		 * d-C-1 | /
1558 		 *       |/         <- greater is better
1559 		 *   -C  /             if scope is not enough for destination.
1560 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1561 		 *
1562 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1563 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1564 		 * Assume B = 0 and we get C > 29.
1565 		 */
1566 		ret = __ipv6_addr_src_scope(score->addr_type);
1567 		if (ret >= dst->scope)
1568 			ret = -ret;
1569 		else
1570 			ret -= 128;	/* 30 is enough */
1571 		score->scopedist = ret;
1572 		break;
1573 	case IPV6_SADDR_RULE_PREFERRED:
1574 	    {
1575 		/* Rule 3: Avoid deprecated and optimistic addresses */
1576 		u8 avoid = IFA_F_DEPRECATED;
1577 
1578 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1579 			avoid |= IFA_F_OPTIMISTIC;
1580 		ret = ipv6_saddr_preferred(score->addr_type) ||
1581 		      !(score->ifa->flags & avoid);
1582 		break;
1583 	    }
1584 #ifdef CONFIG_IPV6_MIP6
1585 	case IPV6_SADDR_RULE_HOA:
1586 	    {
1587 		/* Rule 4: Prefer home address */
1588 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1589 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1590 		break;
1591 	    }
1592 #endif
1593 	case IPV6_SADDR_RULE_OIF:
1594 		/* Rule 5: Prefer outgoing interface */
1595 		ret = (!dst->ifindex ||
1596 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1597 		break;
1598 	case IPV6_SADDR_RULE_LABEL:
1599 		/* Rule 6: Prefer matching label */
1600 		ret = ipv6_addr_label(net,
1601 				      &score->ifa->addr, score->addr_type,
1602 				      score->ifa->idev->dev->ifindex) == dst->label;
1603 		break;
1604 	case IPV6_SADDR_RULE_PRIVACY:
1605 	    {
1606 		/* Rule 7: Prefer public address
1607 		 * Note: prefer temporary address if use_tempaddr >= 2
1608 		 */
1609 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1610 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1611 				score->ifa->idev->cnf.use_tempaddr >= 2;
1612 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1613 		break;
1614 	    }
1615 	case IPV6_SADDR_RULE_ORCHID:
1616 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1617 		 *	    non-ORCHID vs non-ORCHID
1618 		 */
1619 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1620 			ipv6_addr_orchid(dst->addr));
1621 		break;
1622 	case IPV6_SADDR_RULE_PREFIX:
1623 		/* Rule 8: Use longest matching prefix */
1624 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1625 		if (ret > score->ifa->prefix_len)
1626 			ret = score->ifa->prefix_len;
1627 		score->matchlen = ret;
1628 		break;
1629 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1630 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1631 		/* Optimistic addresses still have lower precedence than other
1632 		 * preferred addresses.
1633 		 */
1634 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1635 		break;
1636 #endif
1637 	default:
1638 		ret = 0;
1639 	}
1640 
1641 	if (ret)
1642 		__set_bit(i, score->scorebits);
1643 	score->rule = i;
1644 out:
1645 	return ret;
1646 }
1647 
1648 static int __ipv6_dev_get_saddr(struct net *net,
1649 				struct ipv6_saddr_dst *dst,
1650 				struct inet6_dev *idev,
1651 				struct ipv6_saddr_score *scores,
1652 				int hiscore_idx)
1653 {
1654 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1655 
1656 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1657 		int i;
1658 
1659 		/*
1660 		 * - Tentative Address (RFC2462 section 5.4)
1661 		 *  - A tentative address is not considered
1662 		 *    "assigned to an interface" in the traditional
1663 		 *    sense, unless it is also flagged as optimistic.
1664 		 * - Candidate Source Address (section 4)
1665 		 *  - In any case, anycast addresses, multicast
1666 		 *    addresses, and the unspecified address MUST
1667 		 *    NOT be included in a candidate set.
1668 		 */
1669 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1670 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1671 			continue;
1672 
1673 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1674 
1675 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1676 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1677 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1678 					    idev->dev->name);
1679 			continue;
1680 		}
1681 
1682 		score->rule = -1;
1683 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1684 
1685 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1686 			int minihiscore, miniscore;
1687 
1688 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1689 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1690 
1691 			if (minihiscore > miniscore) {
1692 				if (i == IPV6_SADDR_RULE_SCOPE &&
1693 				    score->scopedist > 0) {
1694 					/*
1695 					 * special case:
1696 					 * each remaining entry
1697 					 * has too small (not enough)
1698 					 * scope, because ifa entries
1699 					 * are sorted by their scope
1700 					 * values.
1701 					 */
1702 					goto out;
1703 				}
1704 				break;
1705 			} else if (minihiscore < miniscore) {
1706 				swap(hiscore, score);
1707 				hiscore_idx = 1 - hiscore_idx;
1708 
1709 				/* restore our iterator */
1710 				score->ifa = hiscore->ifa;
1711 
1712 				break;
1713 			}
1714 		}
1715 	}
1716 out:
1717 	return hiscore_idx;
1718 }
1719 
1720 static int ipv6_get_saddr_master(struct net *net,
1721 				 const struct net_device *dst_dev,
1722 				 const struct net_device *master,
1723 				 struct ipv6_saddr_dst *dst,
1724 				 struct ipv6_saddr_score *scores,
1725 				 int hiscore_idx)
1726 {
1727 	struct inet6_dev *idev;
1728 
1729 	idev = __in6_dev_get(dst_dev);
1730 	if (idev)
1731 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1732 						   scores, hiscore_idx);
1733 
1734 	idev = __in6_dev_get(master);
1735 	if (idev)
1736 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1737 						   scores, hiscore_idx);
1738 
1739 	return hiscore_idx;
1740 }
1741 
1742 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1743 		       const struct in6_addr *daddr, unsigned int prefs,
1744 		       struct in6_addr *saddr)
1745 {
1746 	struct ipv6_saddr_score scores[2], *hiscore;
1747 	struct ipv6_saddr_dst dst;
1748 	struct inet6_dev *idev;
1749 	struct net_device *dev;
1750 	int dst_type;
1751 	bool use_oif_addr = false;
1752 	int hiscore_idx = 0;
1753 	int ret = 0;
1754 
1755 	dst_type = __ipv6_addr_type(daddr);
1756 	dst.addr = daddr;
1757 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1758 	dst.scope = __ipv6_addr_src_scope(dst_type);
1759 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1760 	dst.prefs = prefs;
1761 
1762 	scores[hiscore_idx].rule = -1;
1763 	scores[hiscore_idx].ifa = NULL;
1764 
1765 	rcu_read_lock();
1766 
1767 	/* Candidate Source Address (section 4)
1768 	 *  - multicast and link-local destination address,
1769 	 *    the set of candidate source address MUST only
1770 	 *    include addresses assigned to interfaces
1771 	 *    belonging to the same link as the outgoing
1772 	 *    interface.
1773 	 * (- For site-local destination addresses, the
1774 	 *    set of candidate source addresses MUST only
1775 	 *    include addresses assigned to interfaces
1776 	 *    belonging to the same site as the outgoing
1777 	 *    interface.)
1778 	 *  - "It is RECOMMENDED that the candidate source addresses
1779 	 *    be the set of unicast addresses assigned to the
1780 	 *    interface that will be used to send to the destination
1781 	 *    (the 'outgoing' interface)." (RFC 6724)
1782 	 */
1783 	if (dst_dev) {
1784 		idev = __in6_dev_get(dst_dev);
1785 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1786 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1787 		    (idev && idev->cnf.use_oif_addrs_only)) {
1788 			use_oif_addr = true;
1789 		}
1790 	}
1791 
1792 	if (use_oif_addr) {
1793 		if (idev)
1794 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1795 	} else {
1796 		const struct net_device *master;
1797 		int master_idx = 0;
1798 
1799 		/* if dst_dev exists and is enslaved to an L3 device, then
1800 		 * prefer addresses from dst_dev and then the master over
1801 		 * any other enslaved devices in the L3 domain.
1802 		 */
1803 		master = l3mdev_master_dev_rcu(dst_dev);
1804 		if (master) {
1805 			master_idx = master->ifindex;
1806 
1807 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1808 							    master, &dst,
1809 							    scores, hiscore_idx);
1810 
1811 			if (scores[hiscore_idx].ifa)
1812 				goto out;
1813 		}
1814 
1815 		for_each_netdev_rcu(net, dev) {
1816 			/* only consider addresses on devices in the
1817 			 * same L3 domain
1818 			 */
1819 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1820 				continue;
1821 			idev = __in6_dev_get(dev);
1822 			if (!idev)
1823 				continue;
1824 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1825 		}
1826 	}
1827 
1828 out:
1829 	hiscore = &scores[hiscore_idx];
1830 	if (!hiscore->ifa)
1831 		ret = -EADDRNOTAVAIL;
1832 	else
1833 		*saddr = hiscore->ifa->addr;
1834 
1835 	rcu_read_unlock();
1836 	return ret;
1837 }
1838 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1839 
1840 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1841 		      u32 banned_flags)
1842 {
1843 	struct inet6_ifaddr *ifp;
1844 	int err = -EADDRNOTAVAIL;
1845 
1846 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1847 		if (ifp->scope > IFA_LINK)
1848 			break;
1849 		if (ifp->scope == IFA_LINK &&
1850 		    !(ifp->flags & banned_flags)) {
1851 			*addr = ifp->addr;
1852 			err = 0;
1853 			break;
1854 		}
1855 	}
1856 	return err;
1857 }
1858 
1859 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1860 		    u32 banned_flags)
1861 {
1862 	struct inet6_dev *idev;
1863 	int err = -EADDRNOTAVAIL;
1864 
1865 	rcu_read_lock();
1866 	idev = __in6_dev_get(dev);
1867 	if (idev) {
1868 		read_lock_bh(&idev->lock);
1869 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1870 		read_unlock_bh(&idev->lock);
1871 	}
1872 	rcu_read_unlock();
1873 	return err;
1874 }
1875 
1876 static int ipv6_count_addresses(const struct inet6_dev *idev)
1877 {
1878 	const struct inet6_ifaddr *ifp;
1879 	int cnt = 0;
1880 
1881 	rcu_read_lock();
1882 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1883 		cnt++;
1884 	rcu_read_unlock();
1885 	return cnt;
1886 }
1887 
1888 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1889 		  const struct net_device *dev, int strict)
1890 {
1891 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1892 				       strict, IFA_F_TENTATIVE);
1893 }
1894 EXPORT_SYMBOL(ipv6_chk_addr);
1895 
1896 /* device argument is used to find the L3 domain of interest. If
1897  * skip_dev_check is set, then the ifp device is not checked against
1898  * the passed in dev argument. So the 2 cases for addresses checks are:
1899  *   1. does the address exist in the L3 domain that dev is part of
1900  *      (skip_dev_check = true), or
1901  *
1902  *   2. does the address exist on the specific device
1903  *      (skip_dev_check = false)
1904  */
1905 static struct net_device *
1906 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1907 			  const struct net_device *dev, bool skip_dev_check,
1908 			  int strict, u32 banned_flags)
1909 {
1910 	unsigned int hash = inet6_addr_hash(net, addr);
1911 	struct net_device *l3mdev, *ndev;
1912 	struct inet6_ifaddr *ifp;
1913 	u32 ifp_flags;
1914 
1915 	rcu_read_lock();
1916 
1917 	l3mdev = l3mdev_master_dev_rcu(dev);
1918 	if (skip_dev_check)
1919 		dev = NULL;
1920 
1921 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1922 		ndev = ifp->idev->dev;
1923 		if (!net_eq(dev_net(ndev), net))
1924 			continue;
1925 
1926 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1927 			continue;
1928 
1929 		/* Decouple optimistic from tentative for evaluation here.
1930 		 * Ban optimistic addresses explicitly, when required.
1931 		 */
1932 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1933 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1934 			    : ifp->flags;
1935 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1936 		    !(ifp_flags&banned_flags) &&
1937 		    (!dev || ndev == dev ||
1938 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1939 			rcu_read_unlock();
1940 			return ndev;
1941 		}
1942 	}
1943 
1944 	rcu_read_unlock();
1945 	return NULL;
1946 }
1947 
1948 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1949 			    const struct net_device *dev, bool skip_dev_check,
1950 			    int strict, u32 banned_flags)
1951 {
1952 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1953 					 strict, banned_flags) ? 1 : 0;
1954 }
1955 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1956 
1957 
1958 /* Compares an address/prefix_len with addresses on device @dev.
1959  * If one is found it returns true.
1960  */
1961 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1962 	const unsigned int prefix_len, struct net_device *dev)
1963 {
1964 	const struct inet6_ifaddr *ifa;
1965 	const struct inet6_dev *idev;
1966 	bool ret = false;
1967 
1968 	rcu_read_lock();
1969 	idev = __in6_dev_get(dev);
1970 	if (idev) {
1971 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1972 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1973 			if (ret)
1974 				break;
1975 		}
1976 	}
1977 	rcu_read_unlock();
1978 
1979 	return ret;
1980 }
1981 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1982 
1983 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1984 {
1985 	const struct inet6_ifaddr *ifa;
1986 	const struct inet6_dev *idev;
1987 	int	onlink;
1988 
1989 	onlink = 0;
1990 	rcu_read_lock();
1991 	idev = __in6_dev_get(dev);
1992 	if (idev) {
1993 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1994 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1995 						   ifa->prefix_len);
1996 			if (onlink)
1997 				break;
1998 		}
1999 	}
2000 	rcu_read_unlock();
2001 	return onlink;
2002 }
2003 EXPORT_SYMBOL(ipv6_chk_prefix);
2004 
2005 /**
2006  * ipv6_dev_find - find the first device with a given source address.
2007  * @net: the net namespace
2008  * @addr: the source address
2009  * @dev: used to find the L3 domain of interest
2010  *
2011  * The caller should be protected by RCU, or RTNL.
2012  */
2013 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2014 				 struct net_device *dev)
2015 {
2016 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2017 					 IFA_F_TENTATIVE);
2018 }
2019 EXPORT_SYMBOL(ipv6_dev_find);
2020 
2021 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2022 				     struct net_device *dev, int strict)
2023 {
2024 	unsigned int hash = inet6_addr_hash(net, addr);
2025 	struct inet6_ifaddr *ifp, *result = NULL;
2026 
2027 	rcu_read_lock();
2028 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2029 		if (!net_eq(dev_net(ifp->idev->dev), net))
2030 			continue;
2031 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2032 			if (!dev || ifp->idev->dev == dev ||
2033 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2034 				result = ifp;
2035 				in6_ifa_hold(ifp);
2036 				break;
2037 			}
2038 		}
2039 	}
2040 	rcu_read_unlock();
2041 
2042 	return result;
2043 }
2044 
2045 /* Gets referenced address, destroys ifaddr */
2046 
2047 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2048 {
2049 	if (dad_failed)
2050 		ifp->flags |= IFA_F_DADFAILED;
2051 
2052 	if (ifp->flags&IFA_F_TEMPORARY) {
2053 		struct inet6_ifaddr *ifpub;
2054 		spin_lock_bh(&ifp->lock);
2055 		ifpub = ifp->ifpub;
2056 		if (ifpub) {
2057 			in6_ifa_hold(ifpub);
2058 			spin_unlock_bh(&ifp->lock);
2059 			ipv6_create_tempaddr(ifpub, true);
2060 			in6_ifa_put(ifpub);
2061 		} else {
2062 			spin_unlock_bh(&ifp->lock);
2063 		}
2064 		ipv6_del_addr(ifp);
2065 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2066 		spin_lock_bh(&ifp->lock);
2067 		addrconf_del_dad_work(ifp);
2068 		ifp->flags |= IFA_F_TENTATIVE;
2069 		if (dad_failed)
2070 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2071 		spin_unlock_bh(&ifp->lock);
2072 		if (dad_failed)
2073 			ipv6_ifa_notify(0, ifp);
2074 		in6_ifa_put(ifp);
2075 	} else {
2076 		ipv6_del_addr(ifp);
2077 	}
2078 }
2079 
2080 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2081 {
2082 	int err = -ENOENT;
2083 
2084 	spin_lock_bh(&ifp->lock);
2085 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2086 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2087 		err = 0;
2088 	}
2089 	spin_unlock_bh(&ifp->lock);
2090 
2091 	return err;
2092 }
2093 
2094 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2095 {
2096 	struct inet6_dev *idev = ifp->idev;
2097 	struct net *net = dev_net(ifp->idev->dev);
2098 
2099 	if (addrconf_dad_end(ifp)) {
2100 		in6_ifa_put(ifp);
2101 		return;
2102 	}
2103 
2104 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2105 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2106 
2107 	spin_lock_bh(&ifp->lock);
2108 
2109 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2110 		struct in6_addr new_addr;
2111 		struct inet6_ifaddr *ifp2;
2112 		int retries = ifp->stable_privacy_retry + 1;
2113 		struct ifa6_config cfg = {
2114 			.pfx = &new_addr,
2115 			.plen = ifp->prefix_len,
2116 			.ifa_flags = ifp->flags,
2117 			.valid_lft = ifp->valid_lft,
2118 			.preferred_lft = ifp->prefered_lft,
2119 			.scope = ifp->scope,
2120 		};
2121 
2122 		if (retries > net->ipv6.sysctl.idgen_retries) {
2123 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2124 					     ifp->idev->dev->name);
2125 			goto errdad;
2126 		}
2127 
2128 		new_addr = ifp->addr;
2129 		if (ipv6_generate_stable_address(&new_addr, retries,
2130 						 idev))
2131 			goto errdad;
2132 
2133 		spin_unlock_bh(&ifp->lock);
2134 
2135 		if (idev->cnf.max_addresses &&
2136 		    ipv6_count_addresses(idev) >=
2137 		    idev->cnf.max_addresses)
2138 			goto lock_errdad;
2139 
2140 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2141 				     ifp->idev->dev->name);
2142 
2143 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2144 		if (IS_ERR(ifp2))
2145 			goto lock_errdad;
2146 
2147 		spin_lock_bh(&ifp2->lock);
2148 		ifp2->stable_privacy_retry = retries;
2149 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2150 		spin_unlock_bh(&ifp2->lock);
2151 
2152 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2153 		in6_ifa_put(ifp2);
2154 lock_errdad:
2155 		spin_lock_bh(&ifp->lock);
2156 	}
2157 
2158 errdad:
2159 	/* transition from _POSTDAD to _ERRDAD */
2160 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2161 	spin_unlock_bh(&ifp->lock);
2162 
2163 	addrconf_mod_dad_work(ifp, 0);
2164 	in6_ifa_put(ifp);
2165 }
2166 
2167 /* Join to solicited addr multicast group.
2168  * caller must hold RTNL */
2169 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2170 {
2171 	struct in6_addr maddr;
2172 
2173 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2174 		return;
2175 
2176 	addrconf_addr_solict_mult(addr, &maddr);
2177 	ipv6_dev_mc_inc(dev, &maddr);
2178 }
2179 
2180 /* caller must hold RTNL */
2181 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2182 {
2183 	struct in6_addr maddr;
2184 
2185 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2186 		return;
2187 
2188 	addrconf_addr_solict_mult(addr, &maddr);
2189 	__ipv6_dev_mc_dec(idev, &maddr);
2190 }
2191 
2192 /* caller must hold RTNL */
2193 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2194 {
2195 	struct in6_addr addr;
2196 
2197 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2198 		return;
2199 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2200 	if (ipv6_addr_any(&addr))
2201 		return;
2202 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2203 }
2204 
2205 /* caller must hold RTNL */
2206 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2207 {
2208 	struct in6_addr addr;
2209 
2210 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2211 		return;
2212 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2213 	if (ipv6_addr_any(&addr))
2214 		return;
2215 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2216 }
2217 
2218 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2219 {
2220 	switch (dev->addr_len) {
2221 	case ETH_ALEN:
2222 		memcpy(eui, dev->dev_addr, 3);
2223 		eui[3] = 0xFF;
2224 		eui[4] = 0xFE;
2225 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2226 		break;
2227 	case EUI64_ADDR_LEN:
2228 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2229 		eui[0] ^= 2;
2230 		break;
2231 	default:
2232 		return -1;
2233 	}
2234 
2235 	return 0;
2236 }
2237 
2238 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2239 {
2240 	union fwnet_hwaddr *ha;
2241 
2242 	if (dev->addr_len != FWNET_ALEN)
2243 		return -1;
2244 
2245 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2246 
2247 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2248 	eui[0] ^= 2;
2249 	return 0;
2250 }
2251 
2252 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2253 {
2254 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2255 	if (dev->addr_len != ARCNET_ALEN)
2256 		return -1;
2257 	memset(eui, 0, 7);
2258 	eui[7] = *(u8 *)dev->dev_addr;
2259 	return 0;
2260 }
2261 
2262 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2263 {
2264 	if (dev->addr_len != INFINIBAND_ALEN)
2265 		return -1;
2266 	memcpy(eui, dev->dev_addr + 12, 8);
2267 	eui[0] |= 2;
2268 	return 0;
2269 }
2270 
2271 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2272 {
2273 	if (addr == 0)
2274 		return -1;
2275 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2276 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2277 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2278 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2279 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2280 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2281 	eui[1] = 0;
2282 	eui[2] = 0x5E;
2283 	eui[3] = 0xFE;
2284 	memcpy(eui + 4, &addr, 4);
2285 	return 0;
2286 }
2287 
2288 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2289 {
2290 	if (dev->priv_flags & IFF_ISATAP)
2291 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2292 	return -1;
2293 }
2294 
2295 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2296 {
2297 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2298 }
2299 
2300 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2301 {
2302 	memcpy(eui, dev->perm_addr, 3);
2303 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2304 	eui[3] = 0xFF;
2305 	eui[4] = 0xFE;
2306 	eui[0] ^= 2;
2307 	return 0;
2308 }
2309 
2310 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2311 {
2312 	switch (dev->type) {
2313 	case ARPHRD_ETHER:
2314 	case ARPHRD_FDDI:
2315 		return addrconf_ifid_eui48(eui, dev);
2316 	case ARPHRD_ARCNET:
2317 		return addrconf_ifid_arcnet(eui, dev);
2318 	case ARPHRD_INFINIBAND:
2319 		return addrconf_ifid_infiniband(eui, dev);
2320 	case ARPHRD_SIT:
2321 		return addrconf_ifid_sit(eui, dev);
2322 	case ARPHRD_IPGRE:
2323 	case ARPHRD_TUNNEL:
2324 		return addrconf_ifid_gre(eui, dev);
2325 	case ARPHRD_6LOWPAN:
2326 		return addrconf_ifid_6lowpan(eui, dev);
2327 	case ARPHRD_IEEE1394:
2328 		return addrconf_ifid_ieee1394(eui, dev);
2329 	case ARPHRD_TUNNEL6:
2330 	case ARPHRD_IP6GRE:
2331 	case ARPHRD_RAWIP:
2332 		return addrconf_ifid_ip6tnl(eui, dev);
2333 	}
2334 	return -1;
2335 }
2336 
2337 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2338 {
2339 	int err = -1;
2340 	struct inet6_ifaddr *ifp;
2341 
2342 	read_lock_bh(&idev->lock);
2343 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2344 		if (ifp->scope > IFA_LINK)
2345 			break;
2346 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2347 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2348 			err = 0;
2349 			break;
2350 		}
2351 	}
2352 	read_unlock_bh(&idev->lock);
2353 	return err;
2354 }
2355 
2356 /* Generation of a randomized Interface Identifier
2357  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2358  */
2359 
2360 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2361 {
2362 regen:
2363 	get_random_bytes(&addr->s6_addr[8], 8);
2364 
2365 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2366 	 * check if generated address is not inappropriate:
2367 	 *
2368 	 * - Reserved IPv6 Interface Identifiers
2369 	 * - XXX: already assigned to an address on the device
2370 	 */
2371 
2372 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2373 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2374 		goto regen;
2375 
2376 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2377 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2378 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2379 	 */
2380 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2381 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2382 		goto regen;
2383 
2384 	/* Reserved subnet anycast addresses */
2385 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2386 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2387 		goto regen;
2388 }
2389 
2390 /*
2391  *	Add prefix route.
2392  */
2393 
2394 static void
2395 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2396 		      struct net_device *dev, unsigned long expires,
2397 		      u32 flags, gfp_t gfp_flags)
2398 {
2399 	struct fib6_config cfg = {
2400 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2401 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2402 		.fc_ifindex = dev->ifindex,
2403 		.fc_expires = expires,
2404 		.fc_dst_len = plen,
2405 		.fc_flags = RTF_UP | flags,
2406 		.fc_nlinfo.nl_net = dev_net(dev),
2407 		.fc_protocol = RTPROT_KERNEL,
2408 		.fc_type = RTN_UNICAST,
2409 	};
2410 
2411 	cfg.fc_dst = *pfx;
2412 
2413 	/* Prevent useless cloning on PtP SIT.
2414 	   This thing is done here expecting that the whole
2415 	   class of non-broadcast devices need not cloning.
2416 	 */
2417 #if IS_ENABLED(CONFIG_IPV6_SIT)
2418 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2419 		cfg.fc_flags |= RTF_NONEXTHOP;
2420 #endif
2421 
2422 	ip6_route_add(&cfg, gfp_flags, NULL);
2423 }
2424 
2425 
2426 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2427 						  int plen,
2428 						  const struct net_device *dev,
2429 						  u32 flags, u32 noflags,
2430 						  bool no_gw)
2431 {
2432 	struct fib6_node *fn;
2433 	struct fib6_info *rt = NULL;
2434 	struct fib6_table *table;
2435 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2436 
2437 	table = fib6_get_table(dev_net(dev), tb_id);
2438 	if (!table)
2439 		return NULL;
2440 
2441 	rcu_read_lock();
2442 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2443 	if (!fn)
2444 		goto out;
2445 
2446 	for_each_fib6_node_rt_rcu(fn) {
2447 		/* prefix routes only use builtin fib6_nh */
2448 		if (rt->nh)
2449 			continue;
2450 
2451 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2452 			continue;
2453 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2454 			continue;
2455 		if ((rt->fib6_flags & flags) != flags)
2456 			continue;
2457 		if ((rt->fib6_flags & noflags) != 0)
2458 			continue;
2459 		if (!fib6_info_hold_safe(rt))
2460 			continue;
2461 		break;
2462 	}
2463 out:
2464 	rcu_read_unlock();
2465 	return rt;
2466 }
2467 
2468 
2469 /* Create "default" multicast route to the interface */
2470 
2471 static void addrconf_add_mroute(struct net_device *dev)
2472 {
2473 	struct fib6_config cfg = {
2474 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2475 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2476 		.fc_ifindex = dev->ifindex,
2477 		.fc_dst_len = 8,
2478 		.fc_flags = RTF_UP,
2479 		.fc_type = RTN_MULTICAST,
2480 		.fc_nlinfo.nl_net = dev_net(dev),
2481 		.fc_protocol = RTPROT_KERNEL,
2482 	};
2483 
2484 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2485 
2486 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2487 }
2488 
2489 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2490 {
2491 	struct inet6_dev *idev;
2492 
2493 	ASSERT_RTNL();
2494 
2495 	idev = ipv6_find_idev(dev);
2496 	if (IS_ERR(idev))
2497 		return idev;
2498 
2499 	if (idev->cnf.disable_ipv6)
2500 		return ERR_PTR(-EACCES);
2501 
2502 	/* Add default multicast route */
2503 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2504 		addrconf_add_mroute(dev);
2505 
2506 	return idev;
2507 }
2508 
2509 static void manage_tempaddrs(struct inet6_dev *idev,
2510 			     struct inet6_ifaddr *ifp,
2511 			     __u32 valid_lft, __u32 prefered_lft,
2512 			     bool create, unsigned long now)
2513 {
2514 	u32 flags;
2515 	struct inet6_ifaddr *ift;
2516 
2517 	read_lock_bh(&idev->lock);
2518 	/* update all temporary addresses in the list */
2519 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2520 		int age, max_valid, max_prefered;
2521 
2522 		if (ifp != ift->ifpub)
2523 			continue;
2524 
2525 		/* RFC 4941 section 3.3:
2526 		 * If a received option will extend the lifetime of a public
2527 		 * address, the lifetimes of temporary addresses should
2528 		 * be extended, subject to the overall constraint that no
2529 		 * temporary addresses should ever remain "valid" or "preferred"
2530 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2531 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2532 		 */
2533 		age = (now - ift->cstamp) / HZ;
2534 		max_valid = idev->cnf.temp_valid_lft - age;
2535 		if (max_valid < 0)
2536 			max_valid = 0;
2537 
2538 		max_prefered = idev->cnf.temp_prefered_lft -
2539 			       idev->desync_factor - age;
2540 		if (max_prefered < 0)
2541 			max_prefered = 0;
2542 
2543 		if (valid_lft > max_valid)
2544 			valid_lft = max_valid;
2545 
2546 		if (prefered_lft > max_prefered)
2547 			prefered_lft = max_prefered;
2548 
2549 		spin_lock(&ift->lock);
2550 		flags = ift->flags;
2551 		ift->valid_lft = valid_lft;
2552 		ift->prefered_lft = prefered_lft;
2553 		ift->tstamp = now;
2554 		if (prefered_lft > 0)
2555 			ift->flags &= ~IFA_F_DEPRECATED;
2556 
2557 		spin_unlock(&ift->lock);
2558 		if (!(flags&IFA_F_TENTATIVE))
2559 			ipv6_ifa_notify(0, ift);
2560 	}
2561 
2562 	if ((create || list_empty(&idev->tempaddr_list)) &&
2563 	    idev->cnf.use_tempaddr > 0) {
2564 		/* When a new public address is created as described
2565 		 * in [ADDRCONF], also create a new temporary address.
2566 		 * Also create a temporary address if it's enabled but
2567 		 * no temporary address currently exists.
2568 		 */
2569 		read_unlock_bh(&idev->lock);
2570 		ipv6_create_tempaddr(ifp, false);
2571 	} else {
2572 		read_unlock_bh(&idev->lock);
2573 	}
2574 }
2575 
2576 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2577 {
2578 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2579 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2580 }
2581 
2582 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2583 				 const struct prefix_info *pinfo,
2584 				 struct inet6_dev *in6_dev,
2585 				 const struct in6_addr *addr, int addr_type,
2586 				 u32 addr_flags, bool sllao, bool tokenized,
2587 				 __u32 valid_lft, u32 prefered_lft)
2588 {
2589 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2590 	int create = 0;
2591 
2592 	if (!ifp && valid_lft) {
2593 		int max_addresses = in6_dev->cnf.max_addresses;
2594 		struct ifa6_config cfg = {
2595 			.pfx = addr,
2596 			.plen = pinfo->prefix_len,
2597 			.ifa_flags = addr_flags,
2598 			.valid_lft = valid_lft,
2599 			.preferred_lft = prefered_lft,
2600 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2601 		};
2602 
2603 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2604 		if ((net->ipv6.devconf_all->optimistic_dad ||
2605 		     in6_dev->cnf.optimistic_dad) &&
2606 		    !net->ipv6.devconf_all->forwarding && sllao)
2607 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2608 #endif
2609 
2610 		/* Do not allow to create too much of autoconfigured
2611 		 * addresses; this would be too easy way to crash kernel.
2612 		 */
2613 		if (!max_addresses ||
2614 		    ipv6_count_addresses(in6_dev) < max_addresses)
2615 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2616 
2617 		if (IS_ERR_OR_NULL(ifp))
2618 			return -1;
2619 
2620 		create = 1;
2621 		spin_lock_bh(&ifp->lock);
2622 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2623 		ifp->cstamp = jiffies;
2624 		ifp->tokenized = tokenized;
2625 		spin_unlock_bh(&ifp->lock);
2626 		addrconf_dad_start(ifp);
2627 	}
2628 
2629 	if (ifp) {
2630 		u32 flags;
2631 		unsigned long now;
2632 		u32 stored_lft;
2633 
2634 		/* Update lifetime (RFC4862 5.5.3 e)
2635 		 * We deviate from RFC4862 by honoring all Valid Lifetimes to
2636 		 * improve the reaction of SLAAC to renumbering events
2637 		 * (draft-gont-6man-slaac-renum-06, Section 4.2)
2638 		 */
2639 		spin_lock_bh(&ifp->lock);
2640 		now = jiffies;
2641 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2642 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2643 		else
2644 			stored_lft = 0;
2645 
2646 		if (!create && stored_lft) {
2647 			ifp->valid_lft = valid_lft;
2648 			ifp->prefered_lft = prefered_lft;
2649 			ifp->tstamp = now;
2650 			flags = ifp->flags;
2651 			ifp->flags &= ~IFA_F_DEPRECATED;
2652 			spin_unlock_bh(&ifp->lock);
2653 
2654 			if (!(flags&IFA_F_TENTATIVE))
2655 				ipv6_ifa_notify(0, ifp);
2656 		} else
2657 			spin_unlock_bh(&ifp->lock);
2658 
2659 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2660 				 create, now);
2661 
2662 		in6_ifa_put(ifp);
2663 		addrconf_verify();
2664 	}
2665 
2666 	return 0;
2667 }
2668 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2669 
2670 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2671 {
2672 	struct prefix_info *pinfo;
2673 	__u32 valid_lft;
2674 	__u32 prefered_lft;
2675 	int addr_type, err;
2676 	u32 addr_flags = 0;
2677 	struct inet6_dev *in6_dev;
2678 	struct net *net = dev_net(dev);
2679 
2680 	pinfo = (struct prefix_info *) opt;
2681 
2682 	if (len < sizeof(struct prefix_info)) {
2683 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2684 		return;
2685 	}
2686 
2687 	/*
2688 	 *	Validation checks ([ADDRCONF], page 19)
2689 	 */
2690 
2691 	addr_type = ipv6_addr_type(&pinfo->prefix);
2692 
2693 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2694 		return;
2695 
2696 	valid_lft = ntohl(pinfo->valid);
2697 	prefered_lft = ntohl(pinfo->prefered);
2698 
2699 	if (prefered_lft > valid_lft) {
2700 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2701 		return;
2702 	}
2703 
2704 	in6_dev = in6_dev_get(dev);
2705 
2706 	if (!in6_dev) {
2707 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2708 				    dev->name);
2709 		return;
2710 	}
2711 
2712 	/*
2713 	 *	Two things going on here:
2714 	 *	1) Add routes for on-link prefixes
2715 	 *	2) Configure prefixes with the auto flag set
2716 	 */
2717 
2718 	if (pinfo->onlink) {
2719 		struct fib6_info *rt;
2720 		unsigned long rt_expires;
2721 
2722 		/* Avoid arithmetic overflow. Really, we could
2723 		 * save rt_expires in seconds, likely valid_lft,
2724 		 * but it would require division in fib gc, that it
2725 		 * not good.
2726 		 */
2727 		if (HZ > USER_HZ)
2728 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2729 		else
2730 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2731 
2732 		if (addrconf_finite_timeout(rt_expires))
2733 			rt_expires *= HZ;
2734 
2735 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2736 					       pinfo->prefix_len,
2737 					       dev,
2738 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2739 					       RTF_DEFAULT, true);
2740 
2741 		if (rt) {
2742 			/* Autoconf prefix route */
2743 			if (valid_lft == 0) {
2744 				ip6_del_rt(net, rt, false);
2745 				rt = NULL;
2746 			} else if (addrconf_finite_timeout(rt_expires)) {
2747 				/* not infinity */
2748 				fib6_set_expires(rt, jiffies + rt_expires);
2749 			} else {
2750 				fib6_clean_expires(rt);
2751 			}
2752 		} else if (valid_lft) {
2753 			clock_t expires = 0;
2754 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2755 			if (addrconf_finite_timeout(rt_expires)) {
2756 				/* not infinity */
2757 				flags |= RTF_EXPIRES;
2758 				expires = jiffies_to_clock_t(rt_expires);
2759 			}
2760 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2761 					      0, dev, expires, flags,
2762 					      GFP_ATOMIC);
2763 		}
2764 		fib6_info_release(rt);
2765 	}
2766 
2767 	/* Try to figure out our local address for this prefix */
2768 
2769 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2770 		struct in6_addr addr;
2771 		bool tokenized = false, dev_addr_generated = false;
2772 
2773 		if (pinfo->prefix_len == 64) {
2774 			memcpy(&addr, &pinfo->prefix, 8);
2775 
2776 			if (!ipv6_addr_any(&in6_dev->token)) {
2777 				read_lock_bh(&in6_dev->lock);
2778 				memcpy(addr.s6_addr + 8,
2779 				       in6_dev->token.s6_addr + 8, 8);
2780 				read_unlock_bh(&in6_dev->lock);
2781 				tokenized = true;
2782 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2783 				   !ipv6_generate_stable_address(&addr, 0,
2784 								 in6_dev)) {
2785 				addr_flags |= IFA_F_STABLE_PRIVACY;
2786 				goto ok;
2787 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2788 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2789 				goto put;
2790 			} else {
2791 				dev_addr_generated = true;
2792 			}
2793 			goto ok;
2794 		}
2795 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2796 				    pinfo->prefix_len);
2797 		goto put;
2798 
2799 ok:
2800 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2801 						   &addr, addr_type,
2802 						   addr_flags, sllao,
2803 						   tokenized, valid_lft,
2804 						   prefered_lft);
2805 		if (err)
2806 			goto put;
2807 
2808 		/* Ignore error case here because previous prefix add addr was
2809 		 * successful which will be notified.
2810 		 */
2811 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2812 					      addr_type, addr_flags, sllao,
2813 					      tokenized, valid_lft,
2814 					      prefered_lft,
2815 					      dev_addr_generated);
2816 	}
2817 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2818 put:
2819 	in6_dev_put(in6_dev);
2820 }
2821 
2822 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2823 		struct in6_ifreq *ireq)
2824 {
2825 	struct ip_tunnel_parm p = { };
2826 	int err;
2827 
2828 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2829 		return -EADDRNOTAVAIL;
2830 
2831 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2832 	p.iph.version = 4;
2833 	p.iph.ihl = 5;
2834 	p.iph.protocol = IPPROTO_IPV6;
2835 	p.iph.ttl = 64;
2836 
2837 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2838 		return -EOPNOTSUPP;
2839 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2840 	if (err)
2841 		return err;
2842 
2843 	dev = __dev_get_by_name(net, p.name);
2844 	if (!dev)
2845 		return -ENOBUFS;
2846 	return dev_open(dev, NULL);
2847 }
2848 
2849 /*
2850  *	Set destination address.
2851  *	Special case for SIT interfaces where we create a new "virtual"
2852  *	device.
2853  */
2854 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2855 {
2856 	struct net_device *dev;
2857 	struct in6_ifreq ireq;
2858 	int err = -ENODEV;
2859 
2860 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2861 		return -ENODEV;
2862 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2863 		return -EFAULT;
2864 
2865 	rtnl_lock();
2866 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2867 	if (dev && dev->type == ARPHRD_SIT)
2868 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2869 	rtnl_unlock();
2870 	return err;
2871 }
2872 
2873 static int ipv6_mc_config(struct sock *sk, bool join,
2874 			  const struct in6_addr *addr, int ifindex)
2875 {
2876 	int ret;
2877 
2878 	ASSERT_RTNL();
2879 
2880 	lock_sock(sk);
2881 	if (join)
2882 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2883 	else
2884 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2885 	release_sock(sk);
2886 
2887 	return ret;
2888 }
2889 
2890 /*
2891  *	Manual configuration of address on an interface
2892  */
2893 static int inet6_addr_add(struct net *net, int ifindex,
2894 			  struct ifa6_config *cfg,
2895 			  struct netlink_ext_ack *extack)
2896 {
2897 	struct inet6_ifaddr *ifp;
2898 	struct inet6_dev *idev;
2899 	struct net_device *dev;
2900 	unsigned long timeout;
2901 	clock_t expires;
2902 	u32 flags;
2903 
2904 	ASSERT_RTNL();
2905 
2906 	if (cfg->plen > 128)
2907 		return -EINVAL;
2908 
2909 	/* check the lifetime */
2910 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2911 		return -EINVAL;
2912 
2913 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2914 		return -EINVAL;
2915 
2916 	dev = __dev_get_by_index(net, ifindex);
2917 	if (!dev)
2918 		return -ENODEV;
2919 
2920 	idev = addrconf_add_dev(dev);
2921 	if (IS_ERR(idev))
2922 		return PTR_ERR(idev);
2923 
2924 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2925 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2926 					 true, cfg->pfx, ifindex);
2927 
2928 		if (ret < 0)
2929 			return ret;
2930 	}
2931 
2932 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2933 
2934 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2935 	if (addrconf_finite_timeout(timeout)) {
2936 		expires = jiffies_to_clock_t(timeout * HZ);
2937 		cfg->valid_lft = timeout;
2938 		flags = RTF_EXPIRES;
2939 	} else {
2940 		expires = 0;
2941 		flags = 0;
2942 		cfg->ifa_flags |= IFA_F_PERMANENT;
2943 	}
2944 
2945 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2946 	if (addrconf_finite_timeout(timeout)) {
2947 		if (timeout == 0)
2948 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2949 		cfg->preferred_lft = timeout;
2950 	}
2951 
2952 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2953 	if (!IS_ERR(ifp)) {
2954 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2955 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2956 					      ifp->rt_priority, dev, expires,
2957 					      flags, GFP_KERNEL);
2958 		}
2959 
2960 		/* Send a netlink notification if DAD is enabled and
2961 		 * optimistic flag is not set
2962 		 */
2963 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2964 			ipv6_ifa_notify(0, ifp);
2965 		/*
2966 		 * Note that section 3.1 of RFC 4429 indicates
2967 		 * that the Optimistic flag should not be set for
2968 		 * manually configured addresses
2969 		 */
2970 		addrconf_dad_start(ifp);
2971 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2972 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2973 					 cfg->preferred_lft, true, jiffies);
2974 		in6_ifa_put(ifp);
2975 		addrconf_verify_rtnl();
2976 		return 0;
2977 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2978 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2979 			       cfg->pfx, ifindex);
2980 	}
2981 
2982 	return PTR_ERR(ifp);
2983 }
2984 
2985 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2986 			  const struct in6_addr *pfx, unsigned int plen)
2987 {
2988 	struct inet6_ifaddr *ifp;
2989 	struct inet6_dev *idev;
2990 	struct net_device *dev;
2991 
2992 	if (plen > 128)
2993 		return -EINVAL;
2994 
2995 	dev = __dev_get_by_index(net, ifindex);
2996 	if (!dev)
2997 		return -ENODEV;
2998 
2999 	idev = __in6_dev_get(dev);
3000 	if (!idev)
3001 		return -ENXIO;
3002 
3003 	read_lock_bh(&idev->lock);
3004 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3005 		if (ifp->prefix_len == plen &&
3006 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3007 			in6_ifa_hold(ifp);
3008 			read_unlock_bh(&idev->lock);
3009 
3010 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3011 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3012 				manage_tempaddrs(idev, ifp, 0, 0, false,
3013 						 jiffies);
3014 			ipv6_del_addr(ifp);
3015 			addrconf_verify_rtnl();
3016 			if (ipv6_addr_is_multicast(pfx)) {
3017 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3018 					       false, pfx, dev->ifindex);
3019 			}
3020 			return 0;
3021 		}
3022 	}
3023 	read_unlock_bh(&idev->lock);
3024 	return -EADDRNOTAVAIL;
3025 }
3026 
3027 
3028 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3029 {
3030 	struct ifa6_config cfg = {
3031 		.ifa_flags = IFA_F_PERMANENT,
3032 		.preferred_lft = INFINITY_LIFE_TIME,
3033 		.valid_lft = INFINITY_LIFE_TIME,
3034 	};
3035 	struct in6_ifreq ireq;
3036 	int err;
3037 
3038 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3039 		return -EPERM;
3040 
3041 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3042 		return -EFAULT;
3043 
3044 	cfg.pfx = &ireq.ifr6_addr;
3045 	cfg.plen = ireq.ifr6_prefixlen;
3046 
3047 	rtnl_lock();
3048 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3049 	rtnl_unlock();
3050 	return err;
3051 }
3052 
3053 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3054 {
3055 	struct in6_ifreq ireq;
3056 	int err;
3057 
3058 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3059 		return -EPERM;
3060 
3061 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3062 		return -EFAULT;
3063 
3064 	rtnl_lock();
3065 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3066 			     ireq.ifr6_prefixlen);
3067 	rtnl_unlock();
3068 	return err;
3069 }
3070 
3071 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3072 		     int plen, int scope)
3073 {
3074 	struct inet6_ifaddr *ifp;
3075 	struct ifa6_config cfg = {
3076 		.pfx = addr,
3077 		.plen = plen,
3078 		.ifa_flags = IFA_F_PERMANENT,
3079 		.valid_lft = INFINITY_LIFE_TIME,
3080 		.preferred_lft = INFINITY_LIFE_TIME,
3081 		.scope = scope
3082 	};
3083 
3084 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3085 	if (!IS_ERR(ifp)) {
3086 		spin_lock_bh(&ifp->lock);
3087 		ifp->flags &= ~IFA_F_TENTATIVE;
3088 		spin_unlock_bh(&ifp->lock);
3089 		rt_genid_bump_ipv6(dev_net(idev->dev));
3090 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3091 		in6_ifa_put(ifp);
3092 	}
3093 }
3094 
3095 #if IS_ENABLED(CONFIG_IPV6_SIT)
3096 static void sit_add_v4_addrs(struct inet6_dev *idev)
3097 {
3098 	struct in6_addr addr;
3099 	struct net_device *dev;
3100 	struct net *net = dev_net(idev->dev);
3101 	int scope, plen;
3102 	u32 pflags = 0;
3103 
3104 	ASSERT_RTNL();
3105 
3106 	memset(&addr, 0, sizeof(struct in6_addr));
3107 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3108 
3109 	if (idev->dev->flags&IFF_POINTOPOINT) {
3110 		addr.s6_addr32[0] = htonl(0xfe800000);
3111 		scope = IFA_LINK;
3112 		plen = 64;
3113 	} else {
3114 		scope = IPV6_ADDR_COMPATv4;
3115 		plen = 96;
3116 		pflags |= RTF_NONEXTHOP;
3117 	}
3118 
3119 	if (addr.s6_addr32[3]) {
3120 		add_addr(idev, &addr, plen, scope);
3121 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3122 				      GFP_KERNEL);
3123 		return;
3124 	}
3125 
3126 	for_each_netdev(net, dev) {
3127 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3128 		if (in_dev && (dev->flags & IFF_UP)) {
3129 			struct in_ifaddr *ifa;
3130 			int flag = scope;
3131 
3132 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3133 				addr.s6_addr32[3] = ifa->ifa_local;
3134 
3135 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3136 					continue;
3137 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3138 					if (idev->dev->flags&IFF_POINTOPOINT)
3139 						continue;
3140 					flag |= IFA_HOST;
3141 				}
3142 
3143 				add_addr(idev, &addr, plen, flag);
3144 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3145 						      0, pflags, GFP_KERNEL);
3146 			}
3147 		}
3148 	}
3149 }
3150 #endif
3151 
3152 static void init_loopback(struct net_device *dev)
3153 {
3154 	struct inet6_dev  *idev;
3155 
3156 	/* ::1 */
3157 
3158 	ASSERT_RTNL();
3159 
3160 	idev = ipv6_find_idev(dev);
3161 	if (IS_ERR(idev)) {
3162 		pr_debug("%s: add_dev failed\n", __func__);
3163 		return;
3164 	}
3165 
3166 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3167 }
3168 
3169 void addrconf_add_linklocal(struct inet6_dev *idev,
3170 			    const struct in6_addr *addr, u32 flags)
3171 {
3172 	struct ifa6_config cfg = {
3173 		.pfx = addr,
3174 		.plen = 64,
3175 		.ifa_flags = flags | IFA_F_PERMANENT,
3176 		.valid_lft = INFINITY_LIFE_TIME,
3177 		.preferred_lft = INFINITY_LIFE_TIME,
3178 		.scope = IFA_LINK
3179 	};
3180 	struct inet6_ifaddr *ifp;
3181 
3182 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3183 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3184 	     idev->cnf.optimistic_dad) &&
3185 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3186 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3187 #endif
3188 
3189 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3190 	if (!IS_ERR(ifp)) {
3191 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3192 				      0, 0, GFP_ATOMIC);
3193 		addrconf_dad_start(ifp);
3194 		in6_ifa_put(ifp);
3195 	}
3196 }
3197 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3198 
3199 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3200 {
3201 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3202 		return true;
3203 
3204 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3205 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3206 		return true;
3207 
3208 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3209 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3210 		return true;
3211 
3212 	return false;
3213 }
3214 
3215 static int ipv6_generate_stable_address(struct in6_addr *address,
3216 					u8 dad_count,
3217 					const struct inet6_dev *idev)
3218 {
3219 	static DEFINE_SPINLOCK(lock);
3220 	static __u32 digest[SHA1_DIGEST_WORDS];
3221 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3222 
3223 	static union {
3224 		char __data[SHA1_BLOCK_SIZE];
3225 		struct {
3226 			struct in6_addr secret;
3227 			__be32 prefix[2];
3228 			unsigned char hwaddr[MAX_ADDR_LEN];
3229 			u8 dad_count;
3230 		} __packed;
3231 	} data;
3232 
3233 	struct in6_addr secret;
3234 	struct in6_addr temp;
3235 	struct net *net = dev_net(idev->dev);
3236 
3237 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3238 
3239 	if (idev->cnf.stable_secret.initialized)
3240 		secret = idev->cnf.stable_secret.secret;
3241 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3242 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3243 	else
3244 		return -1;
3245 
3246 retry:
3247 	spin_lock_bh(&lock);
3248 
3249 	sha1_init(digest);
3250 	memset(&data, 0, sizeof(data));
3251 	memset(workspace, 0, sizeof(workspace));
3252 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3253 	data.prefix[0] = address->s6_addr32[0];
3254 	data.prefix[1] = address->s6_addr32[1];
3255 	data.secret = secret;
3256 	data.dad_count = dad_count;
3257 
3258 	sha1_transform(digest, data.__data, workspace);
3259 
3260 	temp = *address;
3261 	temp.s6_addr32[2] = (__force __be32)digest[0];
3262 	temp.s6_addr32[3] = (__force __be32)digest[1];
3263 
3264 	spin_unlock_bh(&lock);
3265 
3266 	if (ipv6_reserved_interfaceid(temp)) {
3267 		dad_count++;
3268 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3269 			return -1;
3270 		goto retry;
3271 	}
3272 
3273 	*address = temp;
3274 	return 0;
3275 }
3276 
3277 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3278 {
3279 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3280 
3281 	if (s->initialized)
3282 		return;
3283 	s = &idev->cnf.stable_secret;
3284 	get_random_bytes(&s->secret, sizeof(s->secret));
3285 	s->initialized = true;
3286 }
3287 
3288 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3289 {
3290 	struct in6_addr addr;
3291 
3292 	/* no link local addresses on L3 master devices */
3293 	if (netif_is_l3_master(idev->dev))
3294 		return;
3295 
3296 	/* no link local addresses on devices flagged as slaves */
3297 	if (idev->dev->flags & IFF_SLAVE)
3298 		return;
3299 
3300 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3301 
3302 	switch (idev->cnf.addr_gen_mode) {
3303 	case IN6_ADDR_GEN_MODE_RANDOM:
3304 		ipv6_gen_mode_random_init(idev);
3305 		fallthrough;
3306 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3307 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3308 			addrconf_add_linklocal(idev, &addr,
3309 					       IFA_F_STABLE_PRIVACY);
3310 		else if (prefix_route)
3311 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3312 					      0, 0, GFP_KERNEL);
3313 		break;
3314 	case IN6_ADDR_GEN_MODE_EUI64:
3315 		/* addrconf_add_linklocal also adds a prefix_route and we
3316 		 * only need to care about prefix routes if ipv6_generate_eui64
3317 		 * couldn't generate one.
3318 		 */
3319 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3320 			addrconf_add_linklocal(idev, &addr, 0);
3321 		else if (prefix_route)
3322 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3323 					      0, 0, GFP_KERNEL);
3324 		break;
3325 	case IN6_ADDR_GEN_MODE_NONE:
3326 	default:
3327 		/* will not add any link local address */
3328 		break;
3329 	}
3330 }
3331 
3332 static void addrconf_dev_config(struct net_device *dev)
3333 {
3334 	struct inet6_dev *idev;
3335 
3336 	ASSERT_RTNL();
3337 
3338 	if ((dev->type != ARPHRD_ETHER) &&
3339 	    (dev->type != ARPHRD_FDDI) &&
3340 	    (dev->type != ARPHRD_ARCNET) &&
3341 	    (dev->type != ARPHRD_INFINIBAND) &&
3342 	    (dev->type != ARPHRD_IEEE1394) &&
3343 	    (dev->type != ARPHRD_TUNNEL6) &&
3344 	    (dev->type != ARPHRD_6LOWPAN) &&
3345 	    (dev->type != ARPHRD_IP6GRE) &&
3346 	    (dev->type != ARPHRD_IPGRE) &&
3347 	    (dev->type != ARPHRD_TUNNEL) &&
3348 	    (dev->type != ARPHRD_NONE) &&
3349 	    (dev->type != ARPHRD_RAWIP)) {
3350 		/* Alas, we support only Ethernet autoconfiguration. */
3351 		idev = __in6_dev_get(dev);
3352 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3353 		    dev->flags & IFF_MULTICAST)
3354 			ipv6_mc_up(idev);
3355 		return;
3356 	}
3357 
3358 	idev = addrconf_add_dev(dev);
3359 	if (IS_ERR(idev))
3360 		return;
3361 
3362 	/* this device type has no EUI support */
3363 	if (dev->type == ARPHRD_NONE &&
3364 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3365 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3366 
3367 	addrconf_addr_gen(idev, false);
3368 }
3369 
3370 #if IS_ENABLED(CONFIG_IPV6_SIT)
3371 static void addrconf_sit_config(struct net_device *dev)
3372 {
3373 	struct inet6_dev *idev;
3374 
3375 	ASSERT_RTNL();
3376 
3377 	/*
3378 	 * Configure the tunnel with one of our IPv4
3379 	 * addresses... we should configure all of
3380 	 * our v4 addrs in the tunnel
3381 	 */
3382 
3383 	idev = ipv6_find_idev(dev);
3384 	if (IS_ERR(idev)) {
3385 		pr_debug("%s: add_dev failed\n", __func__);
3386 		return;
3387 	}
3388 
3389 	if (dev->priv_flags & IFF_ISATAP) {
3390 		addrconf_addr_gen(idev, false);
3391 		return;
3392 	}
3393 
3394 	sit_add_v4_addrs(idev);
3395 
3396 	if (dev->flags&IFF_POINTOPOINT)
3397 		addrconf_add_mroute(dev);
3398 }
3399 #endif
3400 
3401 #if IS_ENABLED(CONFIG_NET_IPGRE)
3402 static void addrconf_gre_config(struct net_device *dev)
3403 {
3404 	struct inet6_dev *idev;
3405 
3406 	ASSERT_RTNL();
3407 
3408 	idev = ipv6_find_idev(dev);
3409 	if (IS_ERR(idev)) {
3410 		pr_debug("%s: add_dev failed\n", __func__);
3411 		return;
3412 	}
3413 
3414 	addrconf_addr_gen(idev, true);
3415 	if (dev->flags & IFF_POINTOPOINT)
3416 		addrconf_add_mroute(dev);
3417 }
3418 #endif
3419 
3420 static int fixup_permanent_addr(struct net *net,
3421 				struct inet6_dev *idev,
3422 				struct inet6_ifaddr *ifp)
3423 {
3424 	/* !fib6_node means the host route was removed from the
3425 	 * FIB, for example, if 'lo' device is taken down. In that
3426 	 * case regenerate the host route.
3427 	 */
3428 	if (!ifp->rt || !ifp->rt->fib6_node) {
3429 		struct fib6_info *f6i, *prev;
3430 
3431 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3432 					 GFP_ATOMIC);
3433 		if (IS_ERR(f6i))
3434 			return PTR_ERR(f6i);
3435 
3436 		/* ifp->rt can be accessed outside of rtnl */
3437 		spin_lock(&ifp->lock);
3438 		prev = ifp->rt;
3439 		ifp->rt = f6i;
3440 		spin_unlock(&ifp->lock);
3441 
3442 		fib6_info_release(prev);
3443 	}
3444 
3445 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3446 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3447 				      ifp->rt_priority, idev->dev, 0, 0,
3448 				      GFP_ATOMIC);
3449 	}
3450 
3451 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3452 		addrconf_dad_start(ifp);
3453 
3454 	return 0;
3455 }
3456 
3457 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3458 {
3459 	struct inet6_ifaddr *ifp, *tmp;
3460 	struct inet6_dev *idev;
3461 
3462 	idev = __in6_dev_get(dev);
3463 	if (!idev)
3464 		return;
3465 
3466 	write_lock_bh(&idev->lock);
3467 
3468 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3469 		if ((ifp->flags & IFA_F_PERMANENT) &&
3470 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3471 			write_unlock_bh(&idev->lock);
3472 			in6_ifa_hold(ifp);
3473 			ipv6_del_addr(ifp);
3474 			write_lock_bh(&idev->lock);
3475 
3476 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3477 					     idev->dev->name, &ifp->addr);
3478 		}
3479 	}
3480 
3481 	write_unlock_bh(&idev->lock);
3482 }
3483 
3484 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3485 			   void *ptr)
3486 {
3487 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3488 	struct netdev_notifier_change_info *change_info;
3489 	struct netdev_notifier_changeupper_info *info;
3490 	struct inet6_dev *idev = __in6_dev_get(dev);
3491 	struct net *net = dev_net(dev);
3492 	int run_pending = 0;
3493 	int err;
3494 
3495 	switch (event) {
3496 	case NETDEV_REGISTER:
3497 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3498 			idev = ipv6_add_dev(dev);
3499 			if (IS_ERR(idev))
3500 				return notifier_from_errno(PTR_ERR(idev));
3501 		}
3502 		break;
3503 
3504 	case NETDEV_CHANGEMTU:
3505 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3506 		if (dev->mtu < IPV6_MIN_MTU) {
3507 			addrconf_ifdown(dev, dev != net->loopback_dev);
3508 			break;
3509 		}
3510 
3511 		if (idev) {
3512 			rt6_mtu_change(dev, dev->mtu);
3513 			idev->cnf.mtu6 = dev->mtu;
3514 			break;
3515 		}
3516 
3517 		/* allocate new idev */
3518 		idev = ipv6_add_dev(dev);
3519 		if (IS_ERR(idev))
3520 			break;
3521 
3522 		/* device is still not ready */
3523 		if (!(idev->if_flags & IF_READY))
3524 			break;
3525 
3526 		run_pending = 1;
3527 		fallthrough;
3528 	case NETDEV_UP:
3529 	case NETDEV_CHANGE:
3530 		if (dev->flags & IFF_SLAVE)
3531 			break;
3532 
3533 		if (idev && idev->cnf.disable_ipv6)
3534 			break;
3535 
3536 		if (event == NETDEV_UP) {
3537 			/* restore routes for permanent addresses */
3538 			addrconf_permanent_addr(net, dev);
3539 
3540 			if (!addrconf_link_ready(dev)) {
3541 				/* device is not ready yet. */
3542 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3543 					 dev->name);
3544 				break;
3545 			}
3546 
3547 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3548 				idev = ipv6_add_dev(dev);
3549 
3550 			if (!IS_ERR_OR_NULL(idev)) {
3551 				idev->if_flags |= IF_READY;
3552 				run_pending = 1;
3553 			}
3554 		} else if (event == NETDEV_CHANGE) {
3555 			if (!addrconf_link_ready(dev)) {
3556 				/* device is still not ready. */
3557 				rt6_sync_down_dev(dev, event);
3558 				break;
3559 			}
3560 
3561 			if (!IS_ERR_OR_NULL(idev)) {
3562 				if (idev->if_flags & IF_READY) {
3563 					/* device is already configured -
3564 					 * but resend MLD reports, we might
3565 					 * have roamed and need to update
3566 					 * multicast snooping switches
3567 					 */
3568 					ipv6_mc_up(idev);
3569 					change_info = ptr;
3570 					if (change_info->flags_changed & IFF_NOARP)
3571 						addrconf_dad_run(idev, true);
3572 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3573 					break;
3574 				}
3575 				idev->if_flags |= IF_READY;
3576 			}
3577 
3578 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3579 				dev->name);
3580 
3581 			run_pending = 1;
3582 		}
3583 
3584 		switch (dev->type) {
3585 #if IS_ENABLED(CONFIG_IPV6_SIT)
3586 		case ARPHRD_SIT:
3587 			addrconf_sit_config(dev);
3588 			break;
3589 #endif
3590 #if IS_ENABLED(CONFIG_NET_IPGRE)
3591 		case ARPHRD_IPGRE:
3592 			addrconf_gre_config(dev);
3593 			break;
3594 #endif
3595 		case ARPHRD_LOOPBACK:
3596 			init_loopback(dev);
3597 			break;
3598 
3599 		default:
3600 			addrconf_dev_config(dev);
3601 			break;
3602 		}
3603 
3604 		if (!IS_ERR_OR_NULL(idev)) {
3605 			if (run_pending)
3606 				addrconf_dad_run(idev, false);
3607 
3608 			/* Device has an address by now */
3609 			rt6_sync_up(dev, RTNH_F_DEAD);
3610 
3611 			/*
3612 			 * If the MTU changed during the interface down,
3613 			 * when the interface up, the changed MTU must be
3614 			 * reflected in the idev as well as routers.
3615 			 */
3616 			if (idev->cnf.mtu6 != dev->mtu &&
3617 			    dev->mtu >= IPV6_MIN_MTU) {
3618 				rt6_mtu_change(dev, dev->mtu);
3619 				idev->cnf.mtu6 = dev->mtu;
3620 			}
3621 			idev->tstamp = jiffies;
3622 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3623 
3624 			/*
3625 			 * If the changed mtu during down is lower than
3626 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3627 			 */
3628 			if (dev->mtu < IPV6_MIN_MTU)
3629 				addrconf_ifdown(dev, dev != net->loopback_dev);
3630 		}
3631 		break;
3632 
3633 	case NETDEV_DOWN:
3634 	case NETDEV_UNREGISTER:
3635 		/*
3636 		 *	Remove all addresses from this interface.
3637 		 */
3638 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3639 		break;
3640 
3641 	case NETDEV_CHANGENAME:
3642 		if (idev) {
3643 			snmp6_unregister_dev(idev);
3644 			addrconf_sysctl_unregister(idev);
3645 			err = addrconf_sysctl_register(idev);
3646 			if (err)
3647 				return notifier_from_errno(err);
3648 			err = snmp6_register_dev(idev);
3649 			if (err) {
3650 				addrconf_sysctl_unregister(idev);
3651 				return notifier_from_errno(err);
3652 			}
3653 		}
3654 		break;
3655 
3656 	case NETDEV_PRE_TYPE_CHANGE:
3657 	case NETDEV_POST_TYPE_CHANGE:
3658 		if (idev)
3659 			addrconf_type_change(dev, event);
3660 		break;
3661 
3662 	case NETDEV_CHANGEUPPER:
3663 		info = ptr;
3664 
3665 		/* flush all routes if dev is linked to or unlinked from
3666 		 * an L3 master device (e.g., VRF)
3667 		 */
3668 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3669 			addrconf_ifdown(dev, false);
3670 	}
3671 
3672 	return NOTIFY_OK;
3673 }
3674 
3675 /*
3676  *	addrconf module should be notified of a device going up
3677  */
3678 static struct notifier_block ipv6_dev_notf = {
3679 	.notifier_call = addrconf_notify,
3680 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3681 };
3682 
3683 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3684 {
3685 	struct inet6_dev *idev;
3686 	ASSERT_RTNL();
3687 
3688 	idev = __in6_dev_get(dev);
3689 
3690 	if (event == NETDEV_POST_TYPE_CHANGE)
3691 		ipv6_mc_remap(idev);
3692 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3693 		ipv6_mc_unmap(idev);
3694 }
3695 
3696 static bool addr_is_local(const struct in6_addr *addr)
3697 {
3698 	return ipv6_addr_type(addr) &
3699 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3700 }
3701 
3702 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3703 {
3704 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3705 	struct net *net = dev_net(dev);
3706 	struct inet6_dev *idev;
3707 	struct inet6_ifaddr *ifa, *tmp;
3708 	bool keep_addr = false;
3709 	int state, i;
3710 
3711 	ASSERT_RTNL();
3712 
3713 	rt6_disable_ip(dev, event);
3714 
3715 	idev = __in6_dev_get(dev);
3716 	if (!idev)
3717 		return -ENODEV;
3718 
3719 	/*
3720 	 * Step 1: remove reference to ipv6 device from parent device.
3721 	 *	   Do not dev_put!
3722 	 */
3723 	if (unregister) {
3724 		idev->dead = 1;
3725 
3726 		/* protected by rtnl_lock */
3727 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3728 
3729 		/* Step 1.5: remove snmp6 entry */
3730 		snmp6_unregister_dev(idev);
3731 
3732 	}
3733 
3734 	/* combine the user config with event to determine if permanent
3735 	 * addresses are to be removed from address hash table
3736 	 */
3737 	if (!unregister && !idev->cnf.disable_ipv6) {
3738 		/* aggregate the system setting and interface setting */
3739 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3740 
3741 		if (!_keep_addr)
3742 			_keep_addr = idev->cnf.keep_addr_on_down;
3743 
3744 		keep_addr = (_keep_addr > 0);
3745 	}
3746 
3747 	/* Step 2: clear hash table */
3748 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3749 		struct hlist_head *h = &inet6_addr_lst[i];
3750 
3751 		spin_lock_bh(&addrconf_hash_lock);
3752 restart:
3753 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3754 			if (ifa->idev == idev) {
3755 				addrconf_del_dad_work(ifa);
3756 				/* combined flag + permanent flag decide if
3757 				 * address is retained on a down event
3758 				 */
3759 				if (!keep_addr ||
3760 				    !(ifa->flags & IFA_F_PERMANENT) ||
3761 				    addr_is_local(&ifa->addr)) {
3762 					hlist_del_init_rcu(&ifa->addr_lst);
3763 					goto restart;
3764 				}
3765 			}
3766 		}
3767 		spin_unlock_bh(&addrconf_hash_lock);
3768 	}
3769 
3770 	write_lock_bh(&idev->lock);
3771 
3772 	addrconf_del_rs_timer(idev);
3773 
3774 	/* Step 2: clear flags for stateless addrconf */
3775 	if (!unregister)
3776 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3777 
3778 	/* Step 3: clear tempaddr list */
3779 	while (!list_empty(&idev->tempaddr_list)) {
3780 		ifa = list_first_entry(&idev->tempaddr_list,
3781 				       struct inet6_ifaddr, tmp_list);
3782 		list_del(&ifa->tmp_list);
3783 		write_unlock_bh(&idev->lock);
3784 		spin_lock_bh(&ifa->lock);
3785 
3786 		if (ifa->ifpub) {
3787 			in6_ifa_put(ifa->ifpub);
3788 			ifa->ifpub = NULL;
3789 		}
3790 		spin_unlock_bh(&ifa->lock);
3791 		in6_ifa_put(ifa);
3792 		write_lock_bh(&idev->lock);
3793 	}
3794 
3795 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3796 		struct fib6_info *rt = NULL;
3797 		bool keep;
3798 
3799 		addrconf_del_dad_work(ifa);
3800 
3801 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3802 			!addr_is_local(&ifa->addr);
3803 
3804 		write_unlock_bh(&idev->lock);
3805 		spin_lock_bh(&ifa->lock);
3806 
3807 		if (keep) {
3808 			/* set state to skip the notifier below */
3809 			state = INET6_IFADDR_STATE_DEAD;
3810 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3811 			if (!(ifa->flags & IFA_F_NODAD))
3812 				ifa->flags |= IFA_F_TENTATIVE;
3813 
3814 			rt = ifa->rt;
3815 			ifa->rt = NULL;
3816 		} else {
3817 			state = ifa->state;
3818 			ifa->state = INET6_IFADDR_STATE_DEAD;
3819 		}
3820 
3821 		spin_unlock_bh(&ifa->lock);
3822 
3823 		if (rt)
3824 			ip6_del_rt(net, rt, false);
3825 
3826 		if (state != INET6_IFADDR_STATE_DEAD) {
3827 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3828 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3829 		} else {
3830 			if (idev->cnf.forwarding)
3831 				addrconf_leave_anycast(ifa);
3832 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3833 		}
3834 
3835 		write_lock_bh(&idev->lock);
3836 		if (!keep) {
3837 			list_del_rcu(&ifa->if_list);
3838 			in6_ifa_put(ifa);
3839 		}
3840 	}
3841 
3842 	write_unlock_bh(&idev->lock);
3843 
3844 	/* Step 5: Discard anycast and multicast list */
3845 	if (unregister) {
3846 		ipv6_ac_destroy_dev(idev);
3847 		ipv6_mc_destroy_dev(idev);
3848 	} else {
3849 		ipv6_mc_down(idev);
3850 	}
3851 
3852 	idev->tstamp = jiffies;
3853 	idev->ra_mtu = 0;
3854 
3855 	/* Last: Shot the device (if unregistered) */
3856 	if (unregister) {
3857 		addrconf_sysctl_unregister(idev);
3858 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3859 		neigh_ifdown(&nd_tbl, dev);
3860 		in6_dev_put(idev);
3861 	}
3862 	return 0;
3863 }
3864 
3865 static void addrconf_rs_timer(struct timer_list *t)
3866 {
3867 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3868 	struct net_device *dev = idev->dev;
3869 	struct in6_addr lladdr;
3870 
3871 	write_lock(&idev->lock);
3872 	if (idev->dead || !(idev->if_flags & IF_READY))
3873 		goto out;
3874 
3875 	if (!ipv6_accept_ra(idev))
3876 		goto out;
3877 
3878 	/* Announcement received after solicitation was sent */
3879 	if (idev->if_flags & IF_RA_RCVD)
3880 		goto out;
3881 
3882 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3883 		write_unlock(&idev->lock);
3884 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3885 			ndisc_send_rs(dev, &lladdr,
3886 				      &in6addr_linklocal_allrouters);
3887 		else
3888 			goto put;
3889 
3890 		write_lock(&idev->lock);
3891 		idev->rs_interval = rfc3315_s14_backoff_update(
3892 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3893 		/* The wait after the last probe can be shorter */
3894 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3895 					     idev->cnf.rtr_solicits) ?
3896 				      idev->cnf.rtr_solicit_delay :
3897 				      idev->rs_interval);
3898 	} else {
3899 		/*
3900 		 * Note: we do not support deprecated "all on-link"
3901 		 * assumption any longer.
3902 		 */
3903 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3904 	}
3905 
3906 out:
3907 	write_unlock(&idev->lock);
3908 put:
3909 	in6_dev_put(idev);
3910 }
3911 
3912 /*
3913  *	Duplicate Address Detection
3914  */
3915 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3916 {
3917 	unsigned long rand_num;
3918 	struct inet6_dev *idev = ifp->idev;
3919 	u64 nonce;
3920 
3921 	if (ifp->flags & IFA_F_OPTIMISTIC)
3922 		rand_num = 0;
3923 	else
3924 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3925 
3926 	nonce = 0;
3927 	if (idev->cnf.enhanced_dad ||
3928 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3929 		do
3930 			get_random_bytes(&nonce, 6);
3931 		while (nonce == 0);
3932 	}
3933 	ifp->dad_nonce = nonce;
3934 	ifp->dad_probes = idev->cnf.dad_transmits;
3935 	addrconf_mod_dad_work(ifp, rand_num);
3936 }
3937 
3938 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3939 {
3940 	struct inet6_dev *idev = ifp->idev;
3941 	struct net_device *dev = idev->dev;
3942 	bool bump_id, notify = false;
3943 	struct net *net;
3944 
3945 	addrconf_join_solict(dev, &ifp->addr);
3946 
3947 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3948 
3949 	read_lock_bh(&idev->lock);
3950 	spin_lock(&ifp->lock);
3951 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3952 		goto out;
3953 
3954 	net = dev_net(dev);
3955 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3956 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3957 	     idev->cnf.accept_dad < 1) ||
3958 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3959 	    ifp->flags & IFA_F_NODAD) {
3960 		bool send_na = false;
3961 
3962 		if (ifp->flags & IFA_F_TENTATIVE &&
3963 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3964 			send_na = true;
3965 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3966 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3967 		spin_unlock(&ifp->lock);
3968 		read_unlock_bh(&idev->lock);
3969 
3970 		addrconf_dad_completed(ifp, bump_id, send_na);
3971 		return;
3972 	}
3973 
3974 	if (!(idev->if_flags & IF_READY)) {
3975 		spin_unlock(&ifp->lock);
3976 		read_unlock_bh(&idev->lock);
3977 		/*
3978 		 * If the device is not ready:
3979 		 * - keep it tentative if it is a permanent address.
3980 		 * - otherwise, kill it.
3981 		 */
3982 		in6_ifa_hold(ifp);
3983 		addrconf_dad_stop(ifp, 0);
3984 		return;
3985 	}
3986 
3987 	/*
3988 	 * Optimistic nodes can start receiving
3989 	 * Frames right away
3990 	 */
3991 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3992 		ip6_ins_rt(net, ifp->rt);
3993 		if (ipv6_use_optimistic_addr(net, idev)) {
3994 			/* Because optimistic nodes can use this address,
3995 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3996 			 */
3997 			notify = true;
3998 		}
3999 	}
4000 
4001 	addrconf_dad_kick(ifp);
4002 out:
4003 	spin_unlock(&ifp->lock);
4004 	read_unlock_bh(&idev->lock);
4005 	if (notify)
4006 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4007 }
4008 
4009 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4010 {
4011 	bool begin_dad = false;
4012 
4013 	spin_lock_bh(&ifp->lock);
4014 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4015 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4016 		begin_dad = true;
4017 	}
4018 	spin_unlock_bh(&ifp->lock);
4019 
4020 	if (begin_dad)
4021 		addrconf_mod_dad_work(ifp, 0);
4022 }
4023 
4024 static void addrconf_dad_work(struct work_struct *w)
4025 {
4026 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4027 						struct inet6_ifaddr,
4028 						dad_work);
4029 	struct inet6_dev *idev = ifp->idev;
4030 	bool bump_id, disable_ipv6 = false;
4031 	struct in6_addr mcaddr;
4032 
4033 	enum {
4034 		DAD_PROCESS,
4035 		DAD_BEGIN,
4036 		DAD_ABORT,
4037 	} action = DAD_PROCESS;
4038 
4039 	rtnl_lock();
4040 
4041 	spin_lock_bh(&ifp->lock);
4042 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4043 		action = DAD_BEGIN;
4044 		ifp->state = INET6_IFADDR_STATE_DAD;
4045 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4046 		action = DAD_ABORT;
4047 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4048 
4049 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4050 		     idev->cnf.accept_dad > 1) &&
4051 		    !idev->cnf.disable_ipv6 &&
4052 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4053 			struct in6_addr addr;
4054 
4055 			addr.s6_addr32[0] = htonl(0xfe800000);
4056 			addr.s6_addr32[1] = 0;
4057 
4058 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4059 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4060 				/* DAD failed for link-local based on MAC */
4061 				idev->cnf.disable_ipv6 = 1;
4062 
4063 				pr_info("%s: IPv6 being disabled!\n",
4064 					ifp->idev->dev->name);
4065 				disable_ipv6 = true;
4066 			}
4067 		}
4068 	}
4069 	spin_unlock_bh(&ifp->lock);
4070 
4071 	if (action == DAD_BEGIN) {
4072 		addrconf_dad_begin(ifp);
4073 		goto out;
4074 	} else if (action == DAD_ABORT) {
4075 		in6_ifa_hold(ifp);
4076 		addrconf_dad_stop(ifp, 1);
4077 		if (disable_ipv6)
4078 			addrconf_ifdown(idev->dev, false);
4079 		goto out;
4080 	}
4081 
4082 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4083 		goto out;
4084 
4085 	write_lock_bh(&idev->lock);
4086 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4087 		write_unlock_bh(&idev->lock);
4088 		goto out;
4089 	}
4090 
4091 	spin_lock(&ifp->lock);
4092 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4093 		spin_unlock(&ifp->lock);
4094 		write_unlock_bh(&idev->lock);
4095 		goto out;
4096 	}
4097 
4098 	if (ifp->dad_probes == 0) {
4099 		bool send_na = false;
4100 
4101 		/*
4102 		 * DAD was successful
4103 		 */
4104 
4105 		if (ifp->flags & IFA_F_TENTATIVE &&
4106 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4107 			send_na = true;
4108 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4109 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4110 		spin_unlock(&ifp->lock);
4111 		write_unlock_bh(&idev->lock);
4112 
4113 		addrconf_dad_completed(ifp, bump_id, send_na);
4114 
4115 		goto out;
4116 	}
4117 
4118 	ifp->dad_probes--;
4119 	addrconf_mod_dad_work(ifp,
4120 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4121 				  HZ/100));
4122 	spin_unlock(&ifp->lock);
4123 	write_unlock_bh(&idev->lock);
4124 
4125 	/* send a neighbour solicitation for our addr */
4126 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4127 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4128 		      ifp->dad_nonce);
4129 out:
4130 	in6_ifa_put(ifp);
4131 	rtnl_unlock();
4132 }
4133 
4134 /* ifp->idev must be at least read locked */
4135 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4136 {
4137 	struct inet6_ifaddr *ifpiter;
4138 	struct inet6_dev *idev = ifp->idev;
4139 
4140 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4141 		if (ifpiter->scope > IFA_LINK)
4142 			break;
4143 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4144 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4145 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4146 		    IFA_F_PERMANENT)
4147 			return false;
4148 	}
4149 	return true;
4150 }
4151 
4152 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4153 				   bool send_na)
4154 {
4155 	struct net_device *dev = ifp->idev->dev;
4156 	struct in6_addr lladdr;
4157 	bool send_rs, send_mld;
4158 
4159 	addrconf_del_dad_work(ifp);
4160 
4161 	/*
4162 	 *	Configure the address for reception. Now it is valid.
4163 	 */
4164 
4165 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4166 
4167 	/* If added prefix is link local and we are prepared to process
4168 	   router advertisements, start sending router solicitations.
4169 	 */
4170 
4171 	read_lock_bh(&ifp->idev->lock);
4172 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4173 	send_rs = send_mld &&
4174 		  ipv6_accept_ra(ifp->idev) &&
4175 		  ifp->idev->cnf.rtr_solicits != 0 &&
4176 		  (dev->flags&IFF_LOOPBACK) == 0;
4177 	read_unlock_bh(&ifp->idev->lock);
4178 
4179 	/* While dad is in progress mld report's source address is in6_addrany.
4180 	 * Resend with proper ll now.
4181 	 */
4182 	if (send_mld)
4183 		ipv6_mc_dad_complete(ifp->idev);
4184 
4185 	/* send unsolicited NA if enabled */
4186 	if (send_na &&
4187 	    (ifp->idev->cnf.ndisc_notify ||
4188 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4189 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4190 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4191 			      /*solicited=*/ false, /*override=*/ true,
4192 			      /*inc_opt=*/ true);
4193 	}
4194 
4195 	if (send_rs) {
4196 		/*
4197 		 *	If a host as already performed a random delay
4198 		 *	[...] as part of DAD [...] there is no need
4199 		 *	to delay again before sending the first RS
4200 		 */
4201 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4202 			return;
4203 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4204 
4205 		write_lock_bh(&ifp->idev->lock);
4206 		spin_lock(&ifp->lock);
4207 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4208 			ifp->idev->cnf.rtr_solicit_interval);
4209 		ifp->idev->rs_probes = 1;
4210 		ifp->idev->if_flags |= IF_RS_SENT;
4211 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4212 		spin_unlock(&ifp->lock);
4213 		write_unlock_bh(&ifp->idev->lock);
4214 	}
4215 
4216 	if (bump_id)
4217 		rt_genid_bump_ipv6(dev_net(dev));
4218 
4219 	/* Make sure that a new temporary address will be created
4220 	 * before this temporary address becomes deprecated.
4221 	 */
4222 	if (ifp->flags & IFA_F_TEMPORARY)
4223 		addrconf_verify_rtnl();
4224 }
4225 
4226 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4227 {
4228 	struct inet6_ifaddr *ifp;
4229 
4230 	read_lock_bh(&idev->lock);
4231 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4232 		spin_lock(&ifp->lock);
4233 		if ((ifp->flags & IFA_F_TENTATIVE &&
4234 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4235 			if (restart)
4236 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4237 			addrconf_dad_kick(ifp);
4238 		}
4239 		spin_unlock(&ifp->lock);
4240 	}
4241 	read_unlock_bh(&idev->lock);
4242 }
4243 
4244 #ifdef CONFIG_PROC_FS
4245 struct if6_iter_state {
4246 	struct seq_net_private p;
4247 	int bucket;
4248 	int offset;
4249 };
4250 
4251 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4252 {
4253 	struct if6_iter_state *state = seq->private;
4254 	struct net *net = seq_file_net(seq);
4255 	struct inet6_ifaddr *ifa = NULL;
4256 	int p = 0;
4257 
4258 	/* initial bucket if pos is 0 */
4259 	if (pos == 0) {
4260 		state->bucket = 0;
4261 		state->offset = 0;
4262 	}
4263 
4264 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4265 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4266 					 addr_lst) {
4267 			if (!net_eq(dev_net(ifa->idev->dev), net))
4268 				continue;
4269 			/* sync with offset */
4270 			if (p < state->offset) {
4271 				p++;
4272 				continue;
4273 			}
4274 			return ifa;
4275 		}
4276 
4277 		/* prepare for next bucket */
4278 		state->offset = 0;
4279 		p = 0;
4280 	}
4281 	return NULL;
4282 }
4283 
4284 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4285 					 struct inet6_ifaddr *ifa)
4286 {
4287 	struct if6_iter_state *state = seq->private;
4288 	struct net *net = seq_file_net(seq);
4289 
4290 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4291 		if (!net_eq(dev_net(ifa->idev->dev), net))
4292 			continue;
4293 		state->offset++;
4294 		return ifa;
4295 	}
4296 
4297 	state->offset = 0;
4298 	while (++state->bucket < IN6_ADDR_HSIZE) {
4299 		hlist_for_each_entry_rcu(ifa,
4300 				     &inet6_addr_lst[state->bucket], addr_lst) {
4301 			if (!net_eq(dev_net(ifa->idev->dev), net))
4302 				continue;
4303 			return ifa;
4304 		}
4305 	}
4306 
4307 	return NULL;
4308 }
4309 
4310 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4311 	__acquires(rcu)
4312 {
4313 	rcu_read_lock();
4314 	return if6_get_first(seq, *pos);
4315 }
4316 
4317 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4318 {
4319 	struct inet6_ifaddr *ifa;
4320 
4321 	ifa = if6_get_next(seq, v);
4322 	++*pos;
4323 	return ifa;
4324 }
4325 
4326 static void if6_seq_stop(struct seq_file *seq, void *v)
4327 	__releases(rcu)
4328 {
4329 	rcu_read_unlock();
4330 }
4331 
4332 static int if6_seq_show(struct seq_file *seq, void *v)
4333 {
4334 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4335 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4336 		   &ifp->addr,
4337 		   ifp->idev->dev->ifindex,
4338 		   ifp->prefix_len,
4339 		   ifp->scope,
4340 		   (u8) ifp->flags,
4341 		   ifp->idev->dev->name);
4342 	return 0;
4343 }
4344 
4345 static const struct seq_operations if6_seq_ops = {
4346 	.start	= if6_seq_start,
4347 	.next	= if6_seq_next,
4348 	.show	= if6_seq_show,
4349 	.stop	= if6_seq_stop,
4350 };
4351 
4352 static int __net_init if6_proc_net_init(struct net *net)
4353 {
4354 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4355 			sizeof(struct if6_iter_state)))
4356 		return -ENOMEM;
4357 	return 0;
4358 }
4359 
4360 static void __net_exit if6_proc_net_exit(struct net *net)
4361 {
4362 	remove_proc_entry("if_inet6", net->proc_net);
4363 }
4364 
4365 static struct pernet_operations if6_proc_net_ops = {
4366 	.init = if6_proc_net_init,
4367 	.exit = if6_proc_net_exit,
4368 };
4369 
4370 int __init if6_proc_init(void)
4371 {
4372 	return register_pernet_subsys(&if6_proc_net_ops);
4373 }
4374 
4375 void if6_proc_exit(void)
4376 {
4377 	unregister_pernet_subsys(&if6_proc_net_ops);
4378 }
4379 #endif	/* CONFIG_PROC_FS */
4380 
4381 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4382 /* Check if address is a home address configured on any interface. */
4383 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4384 {
4385 	unsigned int hash = inet6_addr_hash(net, addr);
4386 	struct inet6_ifaddr *ifp = NULL;
4387 	int ret = 0;
4388 
4389 	rcu_read_lock();
4390 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4391 		if (!net_eq(dev_net(ifp->idev->dev), net))
4392 			continue;
4393 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4394 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4395 			ret = 1;
4396 			break;
4397 		}
4398 	}
4399 	rcu_read_unlock();
4400 	return ret;
4401 }
4402 #endif
4403 
4404 /* RFC6554 has some algorithm to avoid loops in segment routing by
4405  * checking if the segments contains any of a local interface address.
4406  *
4407  * Quote:
4408  *
4409  * To detect loops in the SRH, a router MUST determine if the SRH
4410  * includes multiple addresses assigned to any interface on that router.
4411  * If such addresses appear more than once and are separated by at least
4412  * one address not assigned to that router.
4413  */
4414 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4415 			  unsigned char nsegs)
4416 {
4417 	const struct in6_addr *addr;
4418 	int i, ret = 0, found = 0;
4419 	struct inet6_ifaddr *ifp;
4420 	bool separated = false;
4421 	unsigned int hash;
4422 	bool hash_found;
4423 
4424 	rcu_read_lock();
4425 	for (i = 0; i < nsegs; i++) {
4426 		addr = &segs[i];
4427 		hash = inet6_addr_hash(net, addr);
4428 
4429 		hash_found = false;
4430 		hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4431 			if (!net_eq(dev_net(ifp->idev->dev), net))
4432 				continue;
4433 
4434 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4435 				hash_found = true;
4436 				break;
4437 			}
4438 		}
4439 
4440 		if (hash_found) {
4441 			if (found > 1 && separated) {
4442 				ret = 1;
4443 				break;
4444 			}
4445 
4446 			separated = false;
4447 			found++;
4448 		} else {
4449 			separated = true;
4450 		}
4451 	}
4452 	rcu_read_unlock();
4453 
4454 	return ret;
4455 }
4456 
4457 /*
4458  *	Periodic address status verification
4459  */
4460 
4461 static void addrconf_verify_rtnl(void)
4462 {
4463 	unsigned long now, next, next_sec, next_sched;
4464 	struct inet6_ifaddr *ifp;
4465 	int i;
4466 
4467 	ASSERT_RTNL();
4468 
4469 	rcu_read_lock_bh();
4470 	now = jiffies;
4471 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4472 
4473 	cancel_delayed_work(&addr_chk_work);
4474 
4475 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4476 restart:
4477 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4478 			unsigned long age;
4479 
4480 			/* When setting preferred_lft to a value not zero or
4481 			 * infinity, while valid_lft is infinity
4482 			 * IFA_F_PERMANENT has a non-infinity life time.
4483 			 */
4484 			if ((ifp->flags & IFA_F_PERMANENT) &&
4485 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4486 				continue;
4487 
4488 			spin_lock(&ifp->lock);
4489 			/* We try to batch several events at once. */
4490 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4491 
4492 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4493 			    age >= ifp->valid_lft) {
4494 				spin_unlock(&ifp->lock);
4495 				in6_ifa_hold(ifp);
4496 				rcu_read_unlock_bh();
4497 				ipv6_del_addr(ifp);
4498 				rcu_read_lock_bh();
4499 				goto restart;
4500 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4501 				spin_unlock(&ifp->lock);
4502 				continue;
4503 			} else if (age >= ifp->prefered_lft) {
4504 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4505 				int deprecate = 0;
4506 
4507 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4508 					deprecate = 1;
4509 					ifp->flags |= IFA_F_DEPRECATED;
4510 				}
4511 
4512 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4513 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4514 					next = ifp->tstamp + ifp->valid_lft * HZ;
4515 
4516 				spin_unlock(&ifp->lock);
4517 
4518 				if (deprecate) {
4519 					in6_ifa_hold(ifp);
4520 
4521 					ipv6_ifa_notify(0, ifp);
4522 					in6_ifa_put(ifp);
4523 					goto restart;
4524 				}
4525 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4526 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4527 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4528 					ifp->idev->cnf.dad_transmits *
4529 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4530 
4531 				if (age >= ifp->prefered_lft - regen_advance) {
4532 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4533 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4534 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4535 					if (!ifp->regen_count && ifpub) {
4536 						ifp->regen_count++;
4537 						in6_ifa_hold(ifp);
4538 						in6_ifa_hold(ifpub);
4539 						spin_unlock(&ifp->lock);
4540 
4541 						spin_lock(&ifpub->lock);
4542 						ifpub->regen_count = 0;
4543 						spin_unlock(&ifpub->lock);
4544 						rcu_read_unlock_bh();
4545 						ipv6_create_tempaddr(ifpub, true);
4546 						in6_ifa_put(ifpub);
4547 						in6_ifa_put(ifp);
4548 						rcu_read_lock_bh();
4549 						goto restart;
4550 					}
4551 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4552 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4553 				spin_unlock(&ifp->lock);
4554 			} else {
4555 				/* ifp->prefered_lft <= ifp->valid_lft */
4556 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4557 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4558 				spin_unlock(&ifp->lock);
4559 			}
4560 		}
4561 	}
4562 
4563 	next_sec = round_jiffies_up(next);
4564 	next_sched = next;
4565 
4566 	/* If rounded timeout is accurate enough, accept it. */
4567 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4568 		next_sched = next_sec;
4569 
4570 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4571 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4572 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4573 
4574 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4575 		 now, next, next_sec, next_sched);
4576 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4577 	rcu_read_unlock_bh();
4578 }
4579 
4580 static void addrconf_verify_work(struct work_struct *w)
4581 {
4582 	rtnl_lock();
4583 	addrconf_verify_rtnl();
4584 	rtnl_unlock();
4585 }
4586 
4587 static void addrconf_verify(void)
4588 {
4589 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4590 }
4591 
4592 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4593 				     struct in6_addr **peer_pfx)
4594 {
4595 	struct in6_addr *pfx = NULL;
4596 
4597 	*peer_pfx = NULL;
4598 
4599 	if (addr)
4600 		pfx = nla_data(addr);
4601 
4602 	if (local) {
4603 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4604 			*peer_pfx = pfx;
4605 		pfx = nla_data(local);
4606 	}
4607 
4608 	return pfx;
4609 }
4610 
4611 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4612 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4613 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4614 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4615 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4616 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4617 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4618 };
4619 
4620 static int
4621 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4622 		  struct netlink_ext_ack *extack)
4623 {
4624 	struct net *net = sock_net(skb->sk);
4625 	struct ifaddrmsg *ifm;
4626 	struct nlattr *tb[IFA_MAX+1];
4627 	struct in6_addr *pfx, *peer_pfx;
4628 	u32 ifa_flags;
4629 	int err;
4630 
4631 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4632 				     ifa_ipv6_policy, extack);
4633 	if (err < 0)
4634 		return err;
4635 
4636 	ifm = nlmsg_data(nlh);
4637 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4638 	if (!pfx)
4639 		return -EINVAL;
4640 
4641 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4642 
4643 	/* We ignore other flags so far. */
4644 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4645 
4646 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4647 			      ifm->ifa_prefixlen);
4648 }
4649 
4650 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4651 			       unsigned long expires, u32 flags,
4652 			       bool modify_peer)
4653 {
4654 	struct fib6_info *f6i;
4655 	u32 prio;
4656 
4657 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4658 					ifp->prefix_len,
4659 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4660 	if (!f6i)
4661 		return -ENOENT;
4662 
4663 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4664 	if (f6i->fib6_metric != prio) {
4665 		/* delete old one */
4666 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4667 
4668 		/* add new one */
4669 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4670 				      ifp->prefix_len,
4671 				      ifp->rt_priority, ifp->idev->dev,
4672 				      expires, flags, GFP_KERNEL);
4673 	} else {
4674 		if (!expires)
4675 			fib6_clean_expires(f6i);
4676 		else
4677 			fib6_set_expires(f6i, expires);
4678 
4679 		fib6_info_release(f6i);
4680 	}
4681 
4682 	return 0;
4683 }
4684 
4685 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4686 {
4687 	u32 flags;
4688 	clock_t expires;
4689 	unsigned long timeout;
4690 	bool was_managetempaddr;
4691 	bool had_prefixroute;
4692 	bool new_peer = false;
4693 
4694 	ASSERT_RTNL();
4695 
4696 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4697 		return -EINVAL;
4698 
4699 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4700 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4701 		return -EINVAL;
4702 
4703 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4704 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4705 
4706 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4707 	if (addrconf_finite_timeout(timeout)) {
4708 		expires = jiffies_to_clock_t(timeout * HZ);
4709 		cfg->valid_lft = timeout;
4710 		flags = RTF_EXPIRES;
4711 	} else {
4712 		expires = 0;
4713 		flags = 0;
4714 		cfg->ifa_flags |= IFA_F_PERMANENT;
4715 	}
4716 
4717 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4718 	if (addrconf_finite_timeout(timeout)) {
4719 		if (timeout == 0)
4720 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4721 		cfg->preferred_lft = timeout;
4722 	}
4723 
4724 	if (cfg->peer_pfx &&
4725 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4726 		if (!ipv6_addr_any(&ifp->peer_addr))
4727 			cleanup_prefix_route(ifp, expires, true, true);
4728 		new_peer = true;
4729 	}
4730 
4731 	spin_lock_bh(&ifp->lock);
4732 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4733 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4734 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4735 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4736 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4737 			IFA_F_NOPREFIXROUTE);
4738 	ifp->flags |= cfg->ifa_flags;
4739 	ifp->tstamp = jiffies;
4740 	ifp->valid_lft = cfg->valid_lft;
4741 	ifp->prefered_lft = cfg->preferred_lft;
4742 
4743 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4744 		ifp->rt_priority = cfg->rt_priority;
4745 
4746 	if (new_peer)
4747 		ifp->peer_addr = *cfg->peer_pfx;
4748 
4749 	spin_unlock_bh(&ifp->lock);
4750 	if (!(ifp->flags&IFA_F_TENTATIVE))
4751 		ipv6_ifa_notify(0, ifp);
4752 
4753 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4754 		int rc = -ENOENT;
4755 
4756 		if (had_prefixroute)
4757 			rc = modify_prefix_route(ifp, expires, flags, false);
4758 
4759 		/* prefix route could have been deleted; if so restore it */
4760 		if (rc == -ENOENT) {
4761 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4762 					      ifp->rt_priority, ifp->idev->dev,
4763 					      expires, flags, GFP_KERNEL);
4764 		}
4765 
4766 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4767 			rc = modify_prefix_route(ifp, expires, flags, true);
4768 
4769 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4770 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4771 					      ifp->rt_priority, ifp->idev->dev,
4772 					      expires, flags, GFP_KERNEL);
4773 		}
4774 	} else if (had_prefixroute) {
4775 		enum cleanup_prefix_rt_t action;
4776 		unsigned long rt_expires;
4777 
4778 		write_lock_bh(&ifp->idev->lock);
4779 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4780 		write_unlock_bh(&ifp->idev->lock);
4781 
4782 		if (action != CLEANUP_PREFIX_RT_NOP) {
4783 			cleanup_prefix_route(ifp, rt_expires,
4784 				action == CLEANUP_PREFIX_RT_DEL, false);
4785 		}
4786 	}
4787 
4788 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4789 		if (was_managetempaddr &&
4790 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4791 			cfg->valid_lft = 0;
4792 			cfg->preferred_lft = 0;
4793 		}
4794 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4795 				 cfg->preferred_lft, !was_managetempaddr,
4796 				 jiffies);
4797 	}
4798 
4799 	addrconf_verify_rtnl();
4800 
4801 	return 0;
4802 }
4803 
4804 static int
4805 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4806 		  struct netlink_ext_ack *extack)
4807 {
4808 	struct net *net = sock_net(skb->sk);
4809 	struct ifaddrmsg *ifm;
4810 	struct nlattr *tb[IFA_MAX+1];
4811 	struct in6_addr *peer_pfx;
4812 	struct inet6_ifaddr *ifa;
4813 	struct net_device *dev;
4814 	struct inet6_dev *idev;
4815 	struct ifa6_config cfg;
4816 	int err;
4817 
4818 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4819 				     ifa_ipv6_policy, extack);
4820 	if (err < 0)
4821 		return err;
4822 
4823 	memset(&cfg, 0, sizeof(cfg));
4824 
4825 	ifm = nlmsg_data(nlh);
4826 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4827 	if (!cfg.pfx)
4828 		return -EINVAL;
4829 
4830 	cfg.peer_pfx = peer_pfx;
4831 	cfg.plen = ifm->ifa_prefixlen;
4832 	if (tb[IFA_RT_PRIORITY])
4833 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4834 
4835 	cfg.valid_lft = INFINITY_LIFE_TIME;
4836 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4837 
4838 	if (tb[IFA_CACHEINFO]) {
4839 		struct ifa_cacheinfo *ci;
4840 
4841 		ci = nla_data(tb[IFA_CACHEINFO]);
4842 		cfg.valid_lft = ci->ifa_valid;
4843 		cfg.preferred_lft = ci->ifa_prefered;
4844 	}
4845 
4846 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4847 	if (!dev)
4848 		return -ENODEV;
4849 
4850 	if (tb[IFA_FLAGS])
4851 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4852 	else
4853 		cfg.ifa_flags = ifm->ifa_flags;
4854 
4855 	/* We ignore other flags so far. */
4856 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4857 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4858 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4859 
4860 	idev = ipv6_find_idev(dev);
4861 	if (IS_ERR(idev))
4862 		return PTR_ERR(idev);
4863 
4864 	if (!ipv6_allow_optimistic_dad(net, idev))
4865 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4866 
4867 	if (cfg.ifa_flags & IFA_F_NODAD &&
4868 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4869 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4870 		return -EINVAL;
4871 	}
4872 
4873 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4874 	if (!ifa) {
4875 		/*
4876 		 * It would be best to check for !NLM_F_CREATE here but
4877 		 * userspace already relies on not having to provide this.
4878 		 */
4879 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4880 	}
4881 
4882 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4883 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4884 		err = -EEXIST;
4885 	else
4886 		err = inet6_addr_modify(ifa, &cfg);
4887 
4888 	in6_ifa_put(ifa);
4889 
4890 	return err;
4891 }
4892 
4893 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4894 			  u8 scope, int ifindex)
4895 {
4896 	struct ifaddrmsg *ifm;
4897 
4898 	ifm = nlmsg_data(nlh);
4899 	ifm->ifa_family = AF_INET6;
4900 	ifm->ifa_prefixlen = prefixlen;
4901 	ifm->ifa_flags = flags;
4902 	ifm->ifa_scope = scope;
4903 	ifm->ifa_index = ifindex;
4904 }
4905 
4906 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4907 			 unsigned long tstamp, u32 preferred, u32 valid)
4908 {
4909 	struct ifa_cacheinfo ci;
4910 
4911 	ci.cstamp = cstamp_delta(cstamp);
4912 	ci.tstamp = cstamp_delta(tstamp);
4913 	ci.ifa_prefered = preferred;
4914 	ci.ifa_valid = valid;
4915 
4916 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4917 }
4918 
4919 static inline int rt_scope(int ifa_scope)
4920 {
4921 	if (ifa_scope & IFA_HOST)
4922 		return RT_SCOPE_HOST;
4923 	else if (ifa_scope & IFA_LINK)
4924 		return RT_SCOPE_LINK;
4925 	else if (ifa_scope & IFA_SITE)
4926 		return RT_SCOPE_SITE;
4927 	else
4928 		return RT_SCOPE_UNIVERSE;
4929 }
4930 
4931 static inline int inet6_ifaddr_msgsize(void)
4932 {
4933 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4934 	       + nla_total_size(16) /* IFA_LOCAL */
4935 	       + nla_total_size(16) /* IFA_ADDRESS */
4936 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4937 	       + nla_total_size(4)  /* IFA_FLAGS */
4938 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4939 }
4940 
4941 enum addr_type_t {
4942 	UNICAST_ADDR,
4943 	MULTICAST_ADDR,
4944 	ANYCAST_ADDR,
4945 };
4946 
4947 struct inet6_fill_args {
4948 	u32 portid;
4949 	u32 seq;
4950 	int event;
4951 	unsigned int flags;
4952 	int netnsid;
4953 	int ifindex;
4954 	enum addr_type_t type;
4955 };
4956 
4957 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4958 			     struct inet6_fill_args *args)
4959 {
4960 	struct nlmsghdr  *nlh;
4961 	u32 preferred, valid;
4962 
4963 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4964 			sizeof(struct ifaddrmsg), args->flags);
4965 	if (!nlh)
4966 		return -EMSGSIZE;
4967 
4968 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4969 		      ifa->idev->dev->ifindex);
4970 
4971 	if (args->netnsid >= 0 &&
4972 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4973 		goto error;
4974 
4975 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4976 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4977 		preferred = ifa->prefered_lft;
4978 		valid = ifa->valid_lft;
4979 		if (preferred != INFINITY_LIFE_TIME) {
4980 			long tval = (jiffies - ifa->tstamp)/HZ;
4981 			if (preferred > tval)
4982 				preferred -= tval;
4983 			else
4984 				preferred = 0;
4985 			if (valid != INFINITY_LIFE_TIME) {
4986 				if (valid > tval)
4987 					valid -= tval;
4988 				else
4989 					valid = 0;
4990 			}
4991 		}
4992 	} else {
4993 		preferred = INFINITY_LIFE_TIME;
4994 		valid = INFINITY_LIFE_TIME;
4995 	}
4996 
4997 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4998 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4999 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5000 			goto error;
5001 	} else
5002 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5003 			goto error;
5004 
5005 	if (ifa->rt_priority &&
5006 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
5007 		goto error;
5008 
5009 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5010 		goto error;
5011 
5012 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5013 		goto error;
5014 
5015 	nlmsg_end(skb, nlh);
5016 	return 0;
5017 
5018 error:
5019 	nlmsg_cancel(skb, nlh);
5020 	return -EMSGSIZE;
5021 }
5022 
5023 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5024 			       struct inet6_fill_args *args)
5025 {
5026 	struct nlmsghdr  *nlh;
5027 	u8 scope = RT_SCOPE_UNIVERSE;
5028 	int ifindex = ifmca->idev->dev->ifindex;
5029 
5030 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5031 		scope = RT_SCOPE_SITE;
5032 
5033 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5034 			sizeof(struct ifaddrmsg), args->flags);
5035 	if (!nlh)
5036 		return -EMSGSIZE;
5037 
5038 	if (args->netnsid >= 0 &&
5039 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5040 		nlmsg_cancel(skb, nlh);
5041 		return -EMSGSIZE;
5042 	}
5043 
5044 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5045 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5046 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5047 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5048 		nlmsg_cancel(skb, nlh);
5049 		return -EMSGSIZE;
5050 	}
5051 
5052 	nlmsg_end(skb, nlh);
5053 	return 0;
5054 }
5055 
5056 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5057 			       struct inet6_fill_args *args)
5058 {
5059 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5060 	int ifindex = dev ? dev->ifindex : 1;
5061 	struct nlmsghdr  *nlh;
5062 	u8 scope = RT_SCOPE_UNIVERSE;
5063 
5064 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5065 		scope = RT_SCOPE_SITE;
5066 
5067 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5068 			sizeof(struct ifaddrmsg), args->flags);
5069 	if (!nlh)
5070 		return -EMSGSIZE;
5071 
5072 	if (args->netnsid >= 0 &&
5073 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5074 		nlmsg_cancel(skb, nlh);
5075 		return -EMSGSIZE;
5076 	}
5077 
5078 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5079 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5080 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5081 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5082 		nlmsg_cancel(skb, nlh);
5083 		return -EMSGSIZE;
5084 	}
5085 
5086 	nlmsg_end(skb, nlh);
5087 	return 0;
5088 }
5089 
5090 /* called with rcu_read_lock() */
5091 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5092 			  struct netlink_callback *cb, int s_ip_idx,
5093 			  struct inet6_fill_args *fillargs)
5094 {
5095 	struct ifmcaddr6 *ifmca;
5096 	struct ifacaddr6 *ifaca;
5097 	int ip_idx = 0;
5098 	int err = 1;
5099 
5100 	read_lock_bh(&idev->lock);
5101 	switch (fillargs->type) {
5102 	case UNICAST_ADDR: {
5103 		struct inet6_ifaddr *ifa;
5104 		fillargs->event = RTM_NEWADDR;
5105 
5106 		/* unicast address incl. temp addr */
5107 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5108 			if (ip_idx < s_ip_idx)
5109 				goto next;
5110 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5111 			if (err < 0)
5112 				break;
5113 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5114 next:
5115 			ip_idx++;
5116 		}
5117 		break;
5118 	}
5119 	case MULTICAST_ADDR:
5120 		read_unlock_bh(&idev->lock);
5121 		fillargs->event = RTM_GETMULTICAST;
5122 
5123 		/* multicast address */
5124 		for (ifmca = rcu_dereference(idev->mc_list);
5125 		     ifmca;
5126 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5127 			if (ip_idx < s_ip_idx)
5128 				continue;
5129 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5130 			if (err < 0)
5131 				break;
5132 		}
5133 		read_lock_bh(&idev->lock);
5134 		break;
5135 	case ANYCAST_ADDR:
5136 		fillargs->event = RTM_GETANYCAST;
5137 		/* anycast address */
5138 		for (ifaca = idev->ac_list; ifaca;
5139 		     ifaca = ifaca->aca_next, ip_idx++) {
5140 			if (ip_idx < s_ip_idx)
5141 				continue;
5142 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5143 			if (err < 0)
5144 				break;
5145 		}
5146 		break;
5147 	default:
5148 		break;
5149 	}
5150 	read_unlock_bh(&idev->lock);
5151 	cb->args[2] = ip_idx;
5152 	return err;
5153 }
5154 
5155 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5156 				       struct inet6_fill_args *fillargs,
5157 				       struct net **tgt_net, struct sock *sk,
5158 				       struct netlink_callback *cb)
5159 {
5160 	struct netlink_ext_ack *extack = cb->extack;
5161 	struct nlattr *tb[IFA_MAX+1];
5162 	struct ifaddrmsg *ifm;
5163 	int err, i;
5164 
5165 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5166 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5167 		return -EINVAL;
5168 	}
5169 
5170 	ifm = nlmsg_data(nlh);
5171 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5172 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5173 		return -EINVAL;
5174 	}
5175 
5176 	fillargs->ifindex = ifm->ifa_index;
5177 	if (fillargs->ifindex) {
5178 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5179 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5180 	}
5181 
5182 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5183 					    ifa_ipv6_policy, extack);
5184 	if (err < 0)
5185 		return err;
5186 
5187 	for (i = 0; i <= IFA_MAX; ++i) {
5188 		if (!tb[i])
5189 			continue;
5190 
5191 		if (i == IFA_TARGET_NETNSID) {
5192 			struct net *net;
5193 
5194 			fillargs->netnsid = nla_get_s32(tb[i]);
5195 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5196 			if (IS_ERR(net)) {
5197 				fillargs->netnsid = -1;
5198 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5199 				return PTR_ERR(net);
5200 			}
5201 			*tgt_net = net;
5202 		} else {
5203 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5204 			return -EINVAL;
5205 		}
5206 	}
5207 
5208 	return 0;
5209 }
5210 
5211 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5212 			   enum addr_type_t type)
5213 {
5214 	const struct nlmsghdr *nlh = cb->nlh;
5215 	struct inet6_fill_args fillargs = {
5216 		.portid = NETLINK_CB(cb->skb).portid,
5217 		.seq = cb->nlh->nlmsg_seq,
5218 		.flags = NLM_F_MULTI,
5219 		.netnsid = -1,
5220 		.type = type,
5221 	};
5222 	struct net *tgt_net = sock_net(skb->sk);
5223 	int idx, s_idx, s_ip_idx;
5224 	int h, s_h;
5225 	struct net_device *dev;
5226 	struct inet6_dev *idev;
5227 	struct hlist_head *head;
5228 	int err = 0;
5229 
5230 	s_h = cb->args[0];
5231 	s_idx = idx = cb->args[1];
5232 	s_ip_idx = cb->args[2];
5233 
5234 	if (cb->strict_check) {
5235 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5236 						  skb->sk, cb);
5237 		if (err < 0)
5238 			goto put_tgt_net;
5239 
5240 		err = 0;
5241 		if (fillargs.ifindex) {
5242 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5243 			if (!dev) {
5244 				err = -ENODEV;
5245 				goto put_tgt_net;
5246 			}
5247 			idev = __in6_dev_get(dev);
5248 			if (idev) {
5249 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5250 						     &fillargs);
5251 				if (err > 0)
5252 					err = 0;
5253 			}
5254 			goto put_tgt_net;
5255 		}
5256 	}
5257 
5258 	rcu_read_lock();
5259 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5260 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5261 		idx = 0;
5262 		head = &tgt_net->dev_index_head[h];
5263 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5264 			if (idx < s_idx)
5265 				goto cont;
5266 			if (h > s_h || idx > s_idx)
5267 				s_ip_idx = 0;
5268 			idev = __in6_dev_get(dev);
5269 			if (!idev)
5270 				goto cont;
5271 
5272 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5273 					   &fillargs) < 0)
5274 				goto done;
5275 cont:
5276 			idx++;
5277 		}
5278 	}
5279 done:
5280 	rcu_read_unlock();
5281 	cb->args[0] = h;
5282 	cb->args[1] = idx;
5283 put_tgt_net:
5284 	if (fillargs.netnsid >= 0)
5285 		put_net(tgt_net);
5286 
5287 	return skb->len ? : err;
5288 }
5289 
5290 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5291 {
5292 	enum addr_type_t type = UNICAST_ADDR;
5293 
5294 	return inet6_dump_addr(skb, cb, type);
5295 }
5296 
5297 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5298 {
5299 	enum addr_type_t type = MULTICAST_ADDR;
5300 
5301 	return inet6_dump_addr(skb, cb, type);
5302 }
5303 
5304 
5305 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5306 {
5307 	enum addr_type_t type = ANYCAST_ADDR;
5308 
5309 	return inet6_dump_addr(skb, cb, type);
5310 }
5311 
5312 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5313 				       const struct nlmsghdr *nlh,
5314 				       struct nlattr **tb,
5315 				       struct netlink_ext_ack *extack)
5316 {
5317 	struct ifaddrmsg *ifm;
5318 	int i, err;
5319 
5320 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5321 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5322 		return -EINVAL;
5323 	}
5324 
5325 	if (!netlink_strict_get_check(skb))
5326 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5327 					      ifa_ipv6_policy, extack);
5328 
5329 	ifm = nlmsg_data(nlh);
5330 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5331 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5332 		return -EINVAL;
5333 	}
5334 
5335 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5336 					    ifa_ipv6_policy, extack);
5337 	if (err)
5338 		return err;
5339 
5340 	for (i = 0; i <= IFA_MAX; i++) {
5341 		if (!tb[i])
5342 			continue;
5343 
5344 		switch (i) {
5345 		case IFA_TARGET_NETNSID:
5346 		case IFA_ADDRESS:
5347 		case IFA_LOCAL:
5348 			break;
5349 		default:
5350 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5351 			return -EINVAL;
5352 		}
5353 	}
5354 
5355 	return 0;
5356 }
5357 
5358 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5359 			     struct netlink_ext_ack *extack)
5360 {
5361 	struct net *tgt_net = sock_net(in_skb->sk);
5362 	struct inet6_fill_args fillargs = {
5363 		.portid = NETLINK_CB(in_skb).portid,
5364 		.seq = nlh->nlmsg_seq,
5365 		.event = RTM_NEWADDR,
5366 		.flags = 0,
5367 		.netnsid = -1,
5368 	};
5369 	struct ifaddrmsg *ifm;
5370 	struct nlattr *tb[IFA_MAX+1];
5371 	struct in6_addr *addr = NULL, *peer;
5372 	struct net_device *dev = NULL;
5373 	struct inet6_ifaddr *ifa;
5374 	struct sk_buff *skb;
5375 	int err;
5376 
5377 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5378 	if (err < 0)
5379 		return err;
5380 
5381 	if (tb[IFA_TARGET_NETNSID]) {
5382 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5383 
5384 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5385 						  fillargs.netnsid);
5386 		if (IS_ERR(tgt_net))
5387 			return PTR_ERR(tgt_net);
5388 	}
5389 
5390 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5391 	if (!addr)
5392 		return -EINVAL;
5393 
5394 	ifm = nlmsg_data(nlh);
5395 	if (ifm->ifa_index)
5396 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5397 
5398 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5399 	if (!ifa) {
5400 		err = -EADDRNOTAVAIL;
5401 		goto errout;
5402 	}
5403 
5404 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5405 	if (!skb) {
5406 		err = -ENOBUFS;
5407 		goto errout_ifa;
5408 	}
5409 
5410 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5411 	if (err < 0) {
5412 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5413 		WARN_ON(err == -EMSGSIZE);
5414 		kfree_skb(skb);
5415 		goto errout_ifa;
5416 	}
5417 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5418 errout_ifa:
5419 	in6_ifa_put(ifa);
5420 errout:
5421 	dev_put(dev);
5422 	if (fillargs.netnsid >= 0)
5423 		put_net(tgt_net);
5424 
5425 	return err;
5426 }
5427 
5428 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5429 {
5430 	struct sk_buff *skb;
5431 	struct net *net = dev_net(ifa->idev->dev);
5432 	struct inet6_fill_args fillargs = {
5433 		.portid = 0,
5434 		.seq = 0,
5435 		.event = event,
5436 		.flags = 0,
5437 		.netnsid = -1,
5438 	};
5439 	int err = -ENOBUFS;
5440 
5441 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5442 	if (!skb)
5443 		goto errout;
5444 
5445 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5446 	if (err < 0) {
5447 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5448 		WARN_ON(err == -EMSGSIZE);
5449 		kfree_skb(skb);
5450 		goto errout;
5451 	}
5452 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5453 	return;
5454 errout:
5455 	if (err < 0)
5456 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5457 }
5458 
5459 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5460 				__s32 *array, int bytes)
5461 {
5462 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5463 
5464 	memset(array, 0, bytes);
5465 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5466 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5467 	array[DEVCONF_MTU6] = cnf->mtu6;
5468 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5469 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5470 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5471 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5472 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5473 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5474 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5475 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5476 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5477 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5478 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5479 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5480 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5481 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5482 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5483 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5484 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5485 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5486 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5487 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5488 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5489 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5490 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5491 	array[DEVCONF_RA_DEFRTR_METRIC] = cnf->ra_defrtr_metric;
5492 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5493 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5494 #ifdef CONFIG_IPV6_ROUTER_PREF
5495 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5496 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5497 		jiffies_to_msecs(cnf->rtr_probe_interval);
5498 #ifdef CONFIG_IPV6_ROUTE_INFO
5499 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5500 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5501 #endif
5502 #endif
5503 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5504 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5505 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5506 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5507 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5508 #endif
5509 #ifdef CONFIG_IPV6_MROUTE
5510 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5511 #endif
5512 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5513 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5514 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5515 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5516 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5517 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5518 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5519 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5520 	/* we omit DEVCONF_STABLE_SECRET for now */
5521 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5522 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5523 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5524 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5525 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5526 #ifdef CONFIG_IPV6_SEG6_HMAC
5527 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5528 #endif
5529 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5530 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5531 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5532 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5533 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5534 	array[DEVCONF_IOAM6_ENABLED] = cnf->ioam6_enabled;
5535 	array[DEVCONF_IOAM6_ID] = cnf->ioam6_id;
5536 	array[DEVCONF_IOAM6_ID_WIDE] = cnf->ioam6_id_wide;
5537 }
5538 
5539 static inline size_t inet6_ifla6_size(void)
5540 {
5541 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5542 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5543 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5544 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5545 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5546 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5547 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5548 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5549 	     + 0;
5550 }
5551 
5552 static inline size_t inet6_if_nlmsg_size(void)
5553 {
5554 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5555 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5556 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5557 	       + nla_total_size(4) /* IFLA_MTU */
5558 	       + nla_total_size(4) /* IFLA_LINK */
5559 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5560 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5561 }
5562 
5563 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5564 					int bytes)
5565 {
5566 	int i;
5567 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5568 	BUG_ON(pad < 0);
5569 
5570 	/* Use put_unaligned() because stats may not be aligned for u64. */
5571 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5572 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5573 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5574 
5575 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5576 }
5577 
5578 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5579 					int bytes, size_t syncpoff)
5580 {
5581 	int i, c;
5582 	u64 buff[IPSTATS_MIB_MAX];
5583 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5584 
5585 	BUG_ON(pad < 0);
5586 
5587 	memset(buff, 0, sizeof(buff));
5588 	buff[0] = IPSTATS_MIB_MAX;
5589 
5590 	for_each_possible_cpu(c) {
5591 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5592 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5593 	}
5594 
5595 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5596 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5597 }
5598 
5599 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5600 			     int bytes)
5601 {
5602 	switch (attrtype) {
5603 	case IFLA_INET6_STATS:
5604 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5605 				     offsetof(struct ipstats_mib, syncp));
5606 		break;
5607 	case IFLA_INET6_ICMP6STATS:
5608 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5609 		break;
5610 	}
5611 }
5612 
5613 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5614 				  u32 ext_filter_mask)
5615 {
5616 	struct nlattr *nla;
5617 	struct ifla_cacheinfo ci;
5618 
5619 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5620 		goto nla_put_failure;
5621 	ci.max_reasm_len = IPV6_MAXPLEN;
5622 	ci.tstamp = cstamp_delta(idev->tstamp);
5623 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5624 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5625 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5626 		goto nla_put_failure;
5627 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5628 	if (!nla)
5629 		goto nla_put_failure;
5630 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5631 
5632 	/* XXX - MC not implemented */
5633 
5634 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5635 		return 0;
5636 
5637 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5638 	if (!nla)
5639 		goto nla_put_failure;
5640 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5641 
5642 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5643 	if (!nla)
5644 		goto nla_put_failure;
5645 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5646 
5647 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5648 	if (!nla)
5649 		goto nla_put_failure;
5650 	read_lock_bh(&idev->lock);
5651 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5652 	read_unlock_bh(&idev->lock);
5653 
5654 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5655 		goto nla_put_failure;
5656 
5657 	if (idev->ra_mtu &&
5658 	    nla_put_u32(skb, IFLA_INET6_RA_MTU, idev->ra_mtu))
5659 		goto nla_put_failure;
5660 
5661 	return 0;
5662 
5663 nla_put_failure:
5664 	return -EMSGSIZE;
5665 }
5666 
5667 static size_t inet6_get_link_af_size(const struct net_device *dev,
5668 				     u32 ext_filter_mask)
5669 {
5670 	if (!__in6_dev_get(dev))
5671 		return 0;
5672 
5673 	return inet6_ifla6_size();
5674 }
5675 
5676 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5677 			      u32 ext_filter_mask)
5678 {
5679 	struct inet6_dev *idev = __in6_dev_get(dev);
5680 
5681 	if (!idev)
5682 		return -ENODATA;
5683 
5684 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5685 		return -EMSGSIZE;
5686 
5687 	return 0;
5688 }
5689 
5690 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5691 			     struct netlink_ext_ack *extack)
5692 {
5693 	struct inet6_ifaddr *ifp;
5694 	struct net_device *dev = idev->dev;
5695 	bool clear_token, update_rs = false;
5696 	struct in6_addr ll_addr;
5697 
5698 	ASSERT_RTNL();
5699 
5700 	if (!token)
5701 		return -EINVAL;
5702 
5703 	if (dev->flags & IFF_LOOPBACK) {
5704 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5705 		return -EINVAL;
5706 	}
5707 
5708 	if (dev->flags & IFF_NOARP) {
5709 		NL_SET_ERR_MSG_MOD(extack,
5710 				   "Device does not do neighbour discovery");
5711 		return -EINVAL;
5712 	}
5713 
5714 	if (!ipv6_accept_ra(idev)) {
5715 		NL_SET_ERR_MSG_MOD(extack,
5716 				   "Router advertisement is disabled on device");
5717 		return -EINVAL;
5718 	}
5719 
5720 	if (idev->cnf.rtr_solicits == 0) {
5721 		NL_SET_ERR_MSG(extack,
5722 			       "Router solicitation is disabled on device");
5723 		return -EINVAL;
5724 	}
5725 
5726 	write_lock_bh(&idev->lock);
5727 
5728 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5729 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5730 
5731 	write_unlock_bh(&idev->lock);
5732 
5733 	clear_token = ipv6_addr_any(token);
5734 	if (clear_token)
5735 		goto update_lft;
5736 
5737 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5738 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5739 			     IFA_F_OPTIMISTIC)) {
5740 		/* If we're not ready, then normal ifup will take care
5741 		 * of this. Otherwise, we need to request our rs here.
5742 		 */
5743 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5744 		update_rs = true;
5745 	}
5746 
5747 update_lft:
5748 	write_lock_bh(&idev->lock);
5749 
5750 	if (update_rs) {
5751 		idev->if_flags |= IF_RS_SENT;
5752 		idev->rs_interval = rfc3315_s14_backoff_init(
5753 			idev->cnf.rtr_solicit_interval);
5754 		idev->rs_probes = 1;
5755 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5756 	}
5757 
5758 	/* Well, that's kinda nasty ... */
5759 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5760 		spin_lock(&ifp->lock);
5761 		if (ifp->tokenized) {
5762 			ifp->valid_lft = 0;
5763 			ifp->prefered_lft = 0;
5764 		}
5765 		spin_unlock(&ifp->lock);
5766 	}
5767 
5768 	write_unlock_bh(&idev->lock);
5769 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5770 	addrconf_verify_rtnl();
5771 	return 0;
5772 }
5773 
5774 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5775 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5776 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5777 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5778 					    .reject_message =
5779 						"IFLA_INET6_RA_MTU can not be set" },
5780 };
5781 
5782 static int check_addr_gen_mode(int mode)
5783 {
5784 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5785 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5786 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5787 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5788 		return -EINVAL;
5789 	return 1;
5790 }
5791 
5792 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5793 				int mode)
5794 {
5795 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5796 	    !idev->cnf.stable_secret.initialized &&
5797 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5798 		return -EINVAL;
5799 	return 1;
5800 }
5801 
5802 static int inet6_validate_link_af(const struct net_device *dev,
5803 				  const struct nlattr *nla,
5804 				  struct netlink_ext_ack *extack)
5805 {
5806 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5807 	struct inet6_dev *idev = NULL;
5808 	int err;
5809 
5810 	if (dev) {
5811 		idev = __in6_dev_get(dev);
5812 		if (!idev)
5813 			return -EAFNOSUPPORT;
5814 	}
5815 
5816 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5817 					  inet6_af_policy, extack);
5818 	if (err)
5819 		return err;
5820 
5821 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5822 		return -EINVAL;
5823 
5824 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5825 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5826 
5827 		if (check_addr_gen_mode(mode) < 0)
5828 			return -EINVAL;
5829 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5830 			return -EINVAL;
5831 	}
5832 
5833 	return 0;
5834 }
5835 
5836 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
5837 			     struct netlink_ext_ack *extack)
5838 {
5839 	struct inet6_dev *idev = __in6_dev_get(dev);
5840 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5841 	int err;
5842 
5843 	if (!idev)
5844 		return -EAFNOSUPPORT;
5845 
5846 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5847 		return -EINVAL;
5848 
5849 	if (tb[IFLA_INET6_TOKEN]) {
5850 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
5851 					extack);
5852 		if (err)
5853 			return err;
5854 	}
5855 
5856 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5857 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5858 
5859 		idev->cnf.addr_gen_mode = mode;
5860 	}
5861 
5862 	return 0;
5863 }
5864 
5865 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5866 			     u32 portid, u32 seq, int event, unsigned int flags)
5867 {
5868 	struct net_device *dev = idev->dev;
5869 	struct ifinfomsg *hdr;
5870 	struct nlmsghdr *nlh;
5871 	void *protoinfo;
5872 
5873 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5874 	if (!nlh)
5875 		return -EMSGSIZE;
5876 
5877 	hdr = nlmsg_data(nlh);
5878 	hdr->ifi_family = AF_INET6;
5879 	hdr->__ifi_pad = 0;
5880 	hdr->ifi_type = dev->type;
5881 	hdr->ifi_index = dev->ifindex;
5882 	hdr->ifi_flags = dev_get_flags(dev);
5883 	hdr->ifi_change = 0;
5884 
5885 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5886 	    (dev->addr_len &&
5887 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5888 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5889 	    (dev->ifindex != dev_get_iflink(dev) &&
5890 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5891 	    nla_put_u8(skb, IFLA_OPERSTATE,
5892 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5893 		goto nla_put_failure;
5894 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5895 	if (!protoinfo)
5896 		goto nla_put_failure;
5897 
5898 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5899 		goto nla_put_failure;
5900 
5901 	nla_nest_end(skb, protoinfo);
5902 	nlmsg_end(skb, nlh);
5903 	return 0;
5904 
5905 nla_put_failure:
5906 	nlmsg_cancel(skb, nlh);
5907 	return -EMSGSIZE;
5908 }
5909 
5910 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5911 				   struct netlink_ext_ack *extack)
5912 {
5913 	struct ifinfomsg *ifm;
5914 
5915 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5916 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5917 		return -EINVAL;
5918 	}
5919 
5920 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5921 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5922 		return -EINVAL;
5923 	}
5924 
5925 	ifm = nlmsg_data(nlh);
5926 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5927 	    ifm->ifi_change || ifm->ifi_index) {
5928 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5929 		return -EINVAL;
5930 	}
5931 
5932 	return 0;
5933 }
5934 
5935 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5936 {
5937 	struct net *net = sock_net(skb->sk);
5938 	int h, s_h;
5939 	int idx = 0, s_idx;
5940 	struct net_device *dev;
5941 	struct inet6_dev *idev;
5942 	struct hlist_head *head;
5943 
5944 	/* only requests using strict checking can pass data to
5945 	 * influence the dump
5946 	 */
5947 	if (cb->strict_check) {
5948 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5949 
5950 		if (err < 0)
5951 			return err;
5952 	}
5953 
5954 	s_h = cb->args[0];
5955 	s_idx = cb->args[1];
5956 
5957 	rcu_read_lock();
5958 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5959 		idx = 0;
5960 		head = &net->dev_index_head[h];
5961 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5962 			if (idx < s_idx)
5963 				goto cont;
5964 			idev = __in6_dev_get(dev);
5965 			if (!idev)
5966 				goto cont;
5967 			if (inet6_fill_ifinfo(skb, idev,
5968 					      NETLINK_CB(cb->skb).portid,
5969 					      cb->nlh->nlmsg_seq,
5970 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5971 				goto out;
5972 cont:
5973 			idx++;
5974 		}
5975 	}
5976 out:
5977 	rcu_read_unlock();
5978 	cb->args[1] = idx;
5979 	cb->args[0] = h;
5980 
5981 	return skb->len;
5982 }
5983 
5984 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5985 {
5986 	struct sk_buff *skb;
5987 	struct net *net = dev_net(idev->dev);
5988 	int err = -ENOBUFS;
5989 
5990 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5991 	if (!skb)
5992 		goto errout;
5993 
5994 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5995 	if (err < 0) {
5996 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5997 		WARN_ON(err == -EMSGSIZE);
5998 		kfree_skb(skb);
5999 		goto errout;
6000 	}
6001 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6002 	return;
6003 errout:
6004 	if (err < 0)
6005 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6006 }
6007 
6008 static inline size_t inet6_prefix_nlmsg_size(void)
6009 {
6010 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6011 	       + nla_total_size(sizeof(struct in6_addr))
6012 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6013 }
6014 
6015 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6016 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6017 			     int event, unsigned int flags)
6018 {
6019 	struct prefixmsg *pmsg;
6020 	struct nlmsghdr *nlh;
6021 	struct prefix_cacheinfo	ci;
6022 
6023 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6024 	if (!nlh)
6025 		return -EMSGSIZE;
6026 
6027 	pmsg = nlmsg_data(nlh);
6028 	pmsg->prefix_family = AF_INET6;
6029 	pmsg->prefix_pad1 = 0;
6030 	pmsg->prefix_pad2 = 0;
6031 	pmsg->prefix_ifindex = idev->dev->ifindex;
6032 	pmsg->prefix_len = pinfo->prefix_len;
6033 	pmsg->prefix_type = pinfo->type;
6034 	pmsg->prefix_pad3 = 0;
6035 	pmsg->prefix_flags = 0;
6036 	if (pinfo->onlink)
6037 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
6038 	if (pinfo->autoconf)
6039 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
6040 
6041 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6042 		goto nla_put_failure;
6043 	ci.preferred_time = ntohl(pinfo->prefered);
6044 	ci.valid_time = ntohl(pinfo->valid);
6045 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6046 		goto nla_put_failure;
6047 	nlmsg_end(skb, nlh);
6048 	return 0;
6049 
6050 nla_put_failure:
6051 	nlmsg_cancel(skb, nlh);
6052 	return -EMSGSIZE;
6053 }
6054 
6055 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6056 			 struct prefix_info *pinfo)
6057 {
6058 	struct sk_buff *skb;
6059 	struct net *net = dev_net(idev->dev);
6060 	int err = -ENOBUFS;
6061 
6062 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6063 	if (!skb)
6064 		goto errout;
6065 
6066 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6067 	if (err < 0) {
6068 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6069 		WARN_ON(err == -EMSGSIZE);
6070 		kfree_skb(skb);
6071 		goto errout;
6072 	}
6073 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6074 	return;
6075 errout:
6076 	if (err < 0)
6077 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6078 }
6079 
6080 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6081 {
6082 	struct net *net = dev_net(ifp->idev->dev);
6083 
6084 	if (event)
6085 		ASSERT_RTNL();
6086 
6087 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6088 
6089 	switch (event) {
6090 	case RTM_NEWADDR:
6091 		/*
6092 		 * If the address was optimistic we inserted the route at the
6093 		 * start of our DAD process, so we don't need to do it again.
6094 		 * If the device was taken down in the middle of the DAD
6095 		 * cycle there is a race where we could get here without a
6096 		 * host route, so nothing to insert. That will be fixed when
6097 		 * the device is brought up.
6098 		 */
6099 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6100 			ip6_ins_rt(net, ifp->rt);
6101 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6102 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6103 				&ifp->addr, ifp->idev->dev->name);
6104 		}
6105 
6106 		if (ifp->idev->cnf.forwarding)
6107 			addrconf_join_anycast(ifp);
6108 		if (!ipv6_addr_any(&ifp->peer_addr))
6109 			addrconf_prefix_route(&ifp->peer_addr, 128,
6110 					      ifp->rt_priority, ifp->idev->dev,
6111 					      0, 0, GFP_ATOMIC);
6112 		break;
6113 	case RTM_DELADDR:
6114 		if (ifp->idev->cnf.forwarding)
6115 			addrconf_leave_anycast(ifp);
6116 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6117 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6118 			struct fib6_info *rt;
6119 
6120 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6121 						       ifp->idev->dev, 0, 0,
6122 						       false);
6123 			if (rt)
6124 				ip6_del_rt(net, rt, false);
6125 		}
6126 		if (ifp->rt) {
6127 			ip6_del_rt(net, ifp->rt, false);
6128 			ifp->rt = NULL;
6129 		}
6130 		rt_genid_bump_ipv6(net);
6131 		break;
6132 	}
6133 	atomic_inc(&net->ipv6.dev_addr_genid);
6134 }
6135 
6136 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6137 {
6138 	if (likely(ifp->idev->dead == 0))
6139 		__ipv6_ifa_notify(event, ifp);
6140 }
6141 
6142 #ifdef CONFIG_SYSCTL
6143 
6144 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6145 		void *buffer, size_t *lenp, loff_t *ppos)
6146 {
6147 	int *valp = ctl->data;
6148 	int val = *valp;
6149 	loff_t pos = *ppos;
6150 	struct ctl_table lctl;
6151 	int ret;
6152 
6153 	/*
6154 	 * ctl->data points to idev->cnf.forwarding, we should
6155 	 * not modify it until we get the rtnl lock.
6156 	 */
6157 	lctl = *ctl;
6158 	lctl.data = &val;
6159 
6160 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6161 
6162 	if (write)
6163 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6164 	if (ret)
6165 		*ppos = pos;
6166 	return ret;
6167 }
6168 
6169 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6170 		void *buffer, size_t *lenp, loff_t *ppos)
6171 {
6172 	struct inet6_dev *idev = ctl->extra1;
6173 	int min_mtu = IPV6_MIN_MTU;
6174 	struct ctl_table lctl;
6175 
6176 	lctl = *ctl;
6177 	lctl.extra1 = &min_mtu;
6178 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6179 
6180 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6181 }
6182 
6183 static void dev_disable_change(struct inet6_dev *idev)
6184 {
6185 	struct netdev_notifier_info info;
6186 
6187 	if (!idev || !idev->dev)
6188 		return;
6189 
6190 	netdev_notifier_info_init(&info, idev->dev);
6191 	if (idev->cnf.disable_ipv6)
6192 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6193 	else
6194 		addrconf_notify(NULL, NETDEV_UP, &info);
6195 }
6196 
6197 static void addrconf_disable_change(struct net *net, __s32 newf)
6198 {
6199 	struct net_device *dev;
6200 	struct inet6_dev *idev;
6201 
6202 	for_each_netdev(net, dev) {
6203 		idev = __in6_dev_get(dev);
6204 		if (idev) {
6205 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6206 			idev->cnf.disable_ipv6 = newf;
6207 			if (changed)
6208 				dev_disable_change(idev);
6209 		}
6210 	}
6211 }
6212 
6213 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6214 {
6215 	struct net *net;
6216 	int old;
6217 
6218 	if (!rtnl_trylock())
6219 		return restart_syscall();
6220 
6221 	net = (struct net *)table->extra2;
6222 	old = *p;
6223 	*p = newf;
6224 
6225 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6226 		rtnl_unlock();
6227 		return 0;
6228 	}
6229 
6230 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6231 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6232 		addrconf_disable_change(net, newf);
6233 	} else if ((!newf) ^ (!old))
6234 		dev_disable_change((struct inet6_dev *)table->extra1);
6235 
6236 	rtnl_unlock();
6237 	return 0;
6238 }
6239 
6240 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6241 		void *buffer, size_t *lenp, loff_t *ppos)
6242 {
6243 	int *valp = ctl->data;
6244 	int val = *valp;
6245 	loff_t pos = *ppos;
6246 	struct ctl_table lctl;
6247 	int ret;
6248 
6249 	/*
6250 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6251 	 * not modify it until we get the rtnl lock.
6252 	 */
6253 	lctl = *ctl;
6254 	lctl.data = &val;
6255 
6256 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6257 
6258 	if (write)
6259 		ret = addrconf_disable_ipv6(ctl, valp, val);
6260 	if (ret)
6261 		*ppos = pos;
6262 	return ret;
6263 }
6264 
6265 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6266 		void *buffer, size_t *lenp, loff_t *ppos)
6267 {
6268 	int *valp = ctl->data;
6269 	int ret;
6270 	int old, new;
6271 
6272 	old = *valp;
6273 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6274 	new = *valp;
6275 
6276 	if (write && old != new) {
6277 		struct net *net = ctl->extra2;
6278 
6279 		if (!rtnl_trylock())
6280 			return restart_syscall();
6281 
6282 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6283 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6284 						     NETCONFA_PROXY_NEIGH,
6285 						     NETCONFA_IFINDEX_DEFAULT,
6286 						     net->ipv6.devconf_dflt);
6287 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6288 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6289 						     NETCONFA_PROXY_NEIGH,
6290 						     NETCONFA_IFINDEX_ALL,
6291 						     net->ipv6.devconf_all);
6292 		else {
6293 			struct inet6_dev *idev = ctl->extra1;
6294 
6295 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6296 						     NETCONFA_PROXY_NEIGH,
6297 						     idev->dev->ifindex,
6298 						     &idev->cnf);
6299 		}
6300 		rtnl_unlock();
6301 	}
6302 
6303 	return ret;
6304 }
6305 
6306 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6307 					 void *buffer, size_t *lenp,
6308 					 loff_t *ppos)
6309 {
6310 	int ret = 0;
6311 	u32 new_val;
6312 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6313 	struct net *net = (struct net *)ctl->extra2;
6314 	struct ctl_table tmp = {
6315 		.data = &new_val,
6316 		.maxlen = sizeof(new_val),
6317 		.mode = ctl->mode,
6318 	};
6319 
6320 	if (!rtnl_trylock())
6321 		return restart_syscall();
6322 
6323 	new_val = *((u32 *)ctl->data);
6324 
6325 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6326 	if (ret != 0)
6327 		goto out;
6328 
6329 	if (write) {
6330 		if (check_addr_gen_mode(new_val) < 0) {
6331 			ret = -EINVAL;
6332 			goto out;
6333 		}
6334 
6335 		if (idev) {
6336 			if (check_stable_privacy(idev, net, new_val) < 0) {
6337 				ret = -EINVAL;
6338 				goto out;
6339 			}
6340 
6341 			if (idev->cnf.addr_gen_mode != new_val) {
6342 				idev->cnf.addr_gen_mode = new_val;
6343 				addrconf_dev_config(idev->dev);
6344 			}
6345 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6346 			struct net_device *dev;
6347 
6348 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6349 			for_each_netdev(net, dev) {
6350 				idev = __in6_dev_get(dev);
6351 				if (idev &&
6352 				    idev->cnf.addr_gen_mode != new_val) {
6353 					idev->cnf.addr_gen_mode = new_val;
6354 					addrconf_dev_config(idev->dev);
6355 				}
6356 			}
6357 		}
6358 
6359 		*((u32 *)ctl->data) = new_val;
6360 	}
6361 
6362 out:
6363 	rtnl_unlock();
6364 
6365 	return ret;
6366 }
6367 
6368 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6369 					 void *buffer, size_t *lenp,
6370 					 loff_t *ppos)
6371 {
6372 	int err;
6373 	struct in6_addr addr;
6374 	char str[IPV6_MAX_STRLEN];
6375 	struct ctl_table lctl = *ctl;
6376 	struct net *net = ctl->extra2;
6377 	struct ipv6_stable_secret *secret = ctl->data;
6378 
6379 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6380 		return -EIO;
6381 
6382 	lctl.maxlen = IPV6_MAX_STRLEN;
6383 	lctl.data = str;
6384 
6385 	if (!rtnl_trylock())
6386 		return restart_syscall();
6387 
6388 	if (!write && !secret->initialized) {
6389 		err = -EIO;
6390 		goto out;
6391 	}
6392 
6393 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6394 	if (err >= sizeof(str)) {
6395 		err = -EIO;
6396 		goto out;
6397 	}
6398 
6399 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6400 	if (err || !write)
6401 		goto out;
6402 
6403 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6404 		err = -EIO;
6405 		goto out;
6406 	}
6407 
6408 	secret->initialized = true;
6409 	secret->secret = addr;
6410 
6411 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6412 		struct net_device *dev;
6413 
6414 		for_each_netdev(net, dev) {
6415 			struct inet6_dev *idev = __in6_dev_get(dev);
6416 
6417 			if (idev) {
6418 				idev->cnf.addr_gen_mode =
6419 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6420 			}
6421 		}
6422 	} else {
6423 		struct inet6_dev *idev = ctl->extra1;
6424 
6425 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6426 	}
6427 
6428 out:
6429 	rtnl_unlock();
6430 
6431 	return err;
6432 }
6433 
6434 static
6435 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6436 						int write, void *buffer,
6437 						size_t *lenp,
6438 						loff_t *ppos)
6439 {
6440 	int *valp = ctl->data;
6441 	int val = *valp;
6442 	loff_t pos = *ppos;
6443 	struct ctl_table lctl;
6444 	int ret;
6445 
6446 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6447 	 * we should not modify it until we get the rtnl lock.
6448 	 */
6449 	lctl = *ctl;
6450 	lctl.data = &val;
6451 
6452 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6453 
6454 	if (write)
6455 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6456 	if (ret)
6457 		*ppos = pos;
6458 	return ret;
6459 }
6460 
6461 static
6462 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6463 {
6464 	if (rt) {
6465 		if (action)
6466 			rt->dst.flags |= DST_NOPOLICY;
6467 		else
6468 			rt->dst.flags &= ~DST_NOPOLICY;
6469 	}
6470 }
6471 
6472 static
6473 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6474 {
6475 	struct inet6_ifaddr *ifa;
6476 
6477 	read_lock_bh(&idev->lock);
6478 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6479 		spin_lock(&ifa->lock);
6480 		if (ifa->rt) {
6481 			/* host routes only use builtin fib6_nh */
6482 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6483 			int cpu;
6484 
6485 			rcu_read_lock();
6486 			ifa->rt->dst_nopolicy = val ? true : false;
6487 			if (nh->rt6i_pcpu) {
6488 				for_each_possible_cpu(cpu) {
6489 					struct rt6_info **rtp;
6490 
6491 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6492 					addrconf_set_nopolicy(*rtp, val);
6493 				}
6494 			}
6495 			rcu_read_unlock();
6496 		}
6497 		spin_unlock(&ifa->lock);
6498 	}
6499 	read_unlock_bh(&idev->lock);
6500 }
6501 
6502 static
6503 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6504 {
6505 	struct inet6_dev *idev;
6506 	struct net *net;
6507 
6508 	if (!rtnl_trylock())
6509 		return restart_syscall();
6510 
6511 	*valp = val;
6512 
6513 	net = (struct net *)ctl->extra2;
6514 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6515 		rtnl_unlock();
6516 		return 0;
6517 	}
6518 
6519 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6520 		struct net_device *dev;
6521 
6522 		for_each_netdev(net, dev) {
6523 			idev = __in6_dev_get(dev);
6524 			if (idev)
6525 				addrconf_disable_policy_idev(idev, val);
6526 		}
6527 	} else {
6528 		idev = (struct inet6_dev *)ctl->extra1;
6529 		addrconf_disable_policy_idev(idev, val);
6530 	}
6531 
6532 	rtnl_unlock();
6533 	return 0;
6534 }
6535 
6536 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6537 				   void *buffer, size_t *lenp, loff_t *ppos)
6538 {
6539 	int *valp = ctl->data;
6540 	int val = *valp;
6541 	loff_t pos = *ppos;
6542 	struct ctl_table lctl;
6543 	int ret;
6544 
6545 	lctl = *ctl;
6546 	lctl.data = &val;
6547 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6548 
6549 	if (write && (*valp != val))
6550 		ret = addrconf_disable_policy(ctl, valp, val);
6551 
6552 	if (ret)
6553 		*ppos = pos;
6554 
6555 	return ret;
6556 }
6557 
6558 static int minus_one = -1;
6559 static const int two_five_five = 255;
6560 static u32 ioam6_if_id_max = U16_MAX;
6561 
6562 static const struct ctl_table addrconf_sysctl[] = {
6563 	{
6564 		.procname	= "forwarding",
6565 		.data		= &ipv6_devconf.forwarding,
6566 		.maxlen		= sizeof(int),
6567 		.mode		= 0644,
6568 		.proc_handler	= addrconf_sysctl_forward,
6569 	},
6570 	{
6571 		.procname	= "hop_limit",
6572 		.data		= &ipv6_devconf.hop_limit,
6573 		.maxlen		= sizeof(int),
6574 		.mode		= 0644,
6575 		.proc_handler	= proc_dointvec_minmax,
6576 		.extra1		= (void *)SYSCTL_ONE,
6577 		.extra2		= (void *)&two_five_five,
6578 	},
6579 	{
6580 		.procname	= "mtu",
6581 		.data		= &ipv6_devconf.mtu6,
6582 		.maxlen		= sizeof(int),
6583 		.mode		= 0644,
6584 		.proc_handler	= addrconf_sysctl_mtu,
6585 	},
6586 	{
6587 		.procname	= "accept_ra",
6588 		.data		= &ipv6_devconf.accept_ra,
6589 		.maxlen		= sizeof(int),
6590 		.mode		= 0644,
6591 		.proc_handler	= proc_dointvec,
6592 	},
6593 	{
6594 		.procname	= "accept_redirects",
6595 		.data		= &ipv6_devconf.accept_redirects,
6596 		.maxlen		= sizeof(int),
6597 		.mode		= 0644,
6598 		.proc_handler	= proc_dointvec,
6599 	},
6600 	{
6601 		.procname	= "autoconf",
6602 		.data		= &ipv6_devconf.autoconf,
6603 		.maxlen		= sizeof(int),
6604 		.mode		= 0644,
6605 		.proc_handler	= proc_dointvec,
6606 	},
6607 	{
6608 		.procname	= "dad_transmits",
6609 		.data		= &ipv6_devconf.dad_transmits,
6610 		.maxlen		= sizeof(int),
6611 		.mode		= 0644,
6612 		.proc_handler	= proc_dointvec,
6613 	},
6614 	{
6615 		.procname	= "router_solicitations",
6616 		.data		= &ipv6_devconf.rtr_solicits,
6617 		.maxlen		= sizeof(int),
6618 		.mode		= 0644,
6619 		.proc_handler	= proc_dointvec_minmax,
6620 		.extra1		= &minus_one,
6621 	},
6622 	{
6623 		.procname	= "router_solicitation_interval",
6624 		.data		= &ipv6_devconf.rtr_solicit_interval,
6625 		.maxlen		= sizeof(int),
6626 		.mode		= 0644,
6627 		.proc_handler	= proc_dointvec_jiffies,
6628 	},
6629 	{
6630 		.procname	= "router_solicitation_max_interval",
6631 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6632 		.maxlen		= sizeof(int),
6633 		.mode		= 0644,
6634 		.proc_handler	= proc_dointvec_jiffies,
6635 	},
6636 	{
6637 		.procname	= "router_solicitation_delay",
6638 		.data		= &ipv6_devconf.rtr_solicit_delay,
6639 		.maxlen		= sizeof(int),
6640 		.mode		= 0644,
6641 		.proc_handler	= proc_dointvec_jiffies,
6642 	},
6643 	{
6644 		.procname	= "force_mld_version",
6645 		.data		= &ipv6_devconf.force_mld_version,
6646 		.maxlen		= sizeof(int),
6647 		.mode		= 0644,
6648 		.proc_handler	= proc_dointvec,
6649 	},
6650 	{
6651 		.procname	= "mldv1_unsolicited_report_interval",
6652 		.data		=
6653 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6654 		.maxlen		= sizeof(int),
6655 		.mode		= 0644,
6656 		.proc_handler	= proc_dointvec_ms_jiffies,
6657 	},
6658 	{
6659 		.procname	= "mldv2_unsolicited_report_interval",
6660 		.data		=
6661 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6662 		.maxlen		= sizeof(int),
6663 		.mode		= 0644,
6664 		.proc_handler	= proc_dointvec_ms_jiffies,
6665 	},
6666 	{
6667 		.procname	= "use_tempaddr",
6668 		.data		= &ipv6_devconf.use_tempaddr,
6669 		.maxlen		= sizeof(int),
6670 		.mode		= 0644,
6671 		.proc_handler	= proc_dointvec,
6672 	},
6673 	{
6674 		.procname	= "temp_valid_lft",
6675 		.data		= &ipv6_devconf.temp_valid_lft,
6676 		.maxlen		= sizeof(int),
6677 		.mode		= 0644,
6678 		.proc_handler	= proc_dointvec,
6679 	},
6680 	{
6681 		.procname	= "temp_prefered_lft",
6682 		.data		= &ipv6_devconf.temp_prefered_lft,
6683 		.maxlen		= sizeof(int),
6684 		.mode		= 0644,
6685 		.proc_handler	= proc_dointvec,
6686 	},
6687 	{
6688 		.procname	= "regen_max_retry",
6689 		.data		= &ipv6_devconf.regen_max_retry,
6690 		.maxlen		= sizeof(int),
6691 		.mode		= 0644,
6692 		.proc_handler	= proc_dointvec,
6693 	},
6694 	{
6695 		.procname	= "max_desync_factor",
6696 		.data		= &ipv6_devconf.max_desync_factor,
6697 		.maxlen		= sizeof(int),
6698 		.mode		= 0644,
6699 		.proc_handler	= proc_dointvec,
6700 	},
6701 	{
6702 		.procname	= "max_addresses",
6703 		.data		= &ipv6_devconf.max_addresses,
6704 		.maxlen		= sizeof(int),
6705 		.mode		= 0644,
6706 		.proc_handler	= proc_dointvec,
6707 	},
6708 	{
6709 		.procname	= "accept_ra_defrtr",
6710 		.data		= &ipv6_devconf.accept_ra_defrtr,
6711 		.maxlen		= sizeof(int),
6712 		.mode		= 0644,
6713 		.proc_handler	= proc_dointvec,
6714 	},
6715 	{
6716 		.procname	= "ra_defrtr_metric",
6717 		.data		= &ipv6_devconf.ra_defrtr_metric,
6718 		.maxlen		= sizeof(u32),
6719 		.mode		= 0644,
6720 		.proc_handler	= proc_douintvec_minmax,
6721 		.extra1		= (void *)SYSCTL_ONE,
6722 	},
6723 	{
6724 		.procname	= "accept_ra_min_hop_limit",
6725 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6726 		.maxlen		= sizeof(int),
6727 		.mode		= 0644,
6728 		.proc_handler	= proc_dointvec,
6729 	},
6730 	{
6731 		.procname	= "accept_ra_pinfo",
6732 		.data		= &ipv6_devconf.accept_ra_pinfo,
6733 		.maxlen		= sizeof(int),
6734 		.mode		= 0644,
6735 		.proc_handler	= proc_dointvec,
6736 	},
6737 #ifdef CONFIG_IPV6_ROUTER_PREF
6738 	{
6739 		.procname	= "accept_ra_rtr_pref",
6740 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6741 		.maxlen		= sizeof(int),
6742 		.mode		= 0644,
6743 		.proc_handler	= proc_dointvec,
6744 	},
6745 	{
6746 		.procname	= "router_probe_interval",
6747 		.data		= &ipv6_devconf.rtr_probe_interval,
6748 		.maxlen		= sizeof(int),
6749 		.mode		= 0644,
6750 		.proc_handler	= proc_dointvec_jiffies,
6751 	},
6752 #ifdef CONFIG_IPV6_ROUTE_INFO
6753 	{
6754 		.procname	= "accept_ra_rt_info_min_plen",
6755 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6756 		.maxlen		= sizeof(int),
6757 		.mode		= 0644,
6758 		.proc_handler	= proc_dointvec,
6759 	},
6760 	{
6761 		.procname	= "accept_ra_rt_info_max_plen",
6762 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6763 		.maxlen		= sizeof(int),
6764 		.mode		= 0644,
6765 		.proc_handler	= proc_dointvec,
6766 	},
6767 #endif
6768 #endif
6769 	{
6770 		.procname	= "proxy_ndp",
6771 		.data		= &ipv6_devconf.proxy_ndp,
6772 		.maxlen		= sizeof(int),
6773 		.mode		= 0644,
6774 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6775 	},
6776 	{
6777 		.procname	= "accept_source_route",
6778 		.data		= &ipv6_devconf.accept_source_route,
6779 		.maxlen		= sizeof(int),
6780 		.mode		= 0644,
6781 		.proc_handler	= proc_dointvec,
6782 	},
6783 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6784 	{
6785 		.procname	= "optimistic_dad",
6786 		.data		= &ipv6_devconf.optimistic_dad,
6787 		.maxlen		= sizeof(int),
6788 		.mode		= 0644,
6789 		.proc_handler   = proc_dointvec,
6790 	},
6791 	{
6792 		.procname	= "use_optimistic",
6793 		.data		= &ipv6_devconf.use_optimistic,
6794 		.maxlen		= sizeof(int),
6795 		.mode		= 0644,
6796 		.proc_handler	= proc_dointvec,
6797 	},
6798 #endif
6799 #ifdef CONFIG_IPV6_MROUTE
6800 	{
6801 		.procname	= "mc_forwarding",
6802 		.data		= &ipv6_devconf.mc_forwarding,
6803 		.maxlen		= sizeof(int),
6804 		.mode		= 0444,
6805 		.proc_handler	= proc_dointvec,
6806 	},
6807 #endif
6808 	{
6809 		.procname	= "disable_ipv6",
6810 		.data		= &ipv6_devconf.disable_ipv6,
6811 		.maxlen		= sizeof(int),
6812 		.mode		= 0644,
6813 		.proc_handler	= addrconf_sysctl_disable,
6814 	},
6815 	{
6816 		.procname	= "accept_dad",
6817 		.data		= &ipv6_devconf.accept_dad,
6818 		.maxlen		= sizeof(int),
6819 		.mode		= 0644,
6820 		.proc_handler	= proc_dointvec,
6821 	},
6822 	{
6823 		.procname	= "force_tllao",
6824 		.data		= &ipv6_devconf.force_tllao,
6825 		.maxlen		= sizeof(int),
6826 		.mode		= 0644,
6827 		.proc_handler	= proc_dointvec
6828 	},
6829 	{
6830 		.procname	= "ndisc_notify",
6831 		.data		= &ipv6_devconf.ndisc_notify,
6832 		.maxlen		= sizeof(int),
6833 		.mode		= 0644,
6834 		.proc_handler	= proc_dointvec
6835 	},
6836 	{
6837 		.procname	= "suppress_frag_ndisc",
6838 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6839 		.maxlen		= sizeof(int),
6840 		.mode		= 0644,
6841 		.proc_handler	= proc_dointvec
6842 	},
6843 	{
6844 		.procname	= "accept_ra_from_local",
6845 		.data		= &ipv6_devconf.accept_ra_from_local,
6846 		.maxlen		= sizeof(int),
6847 		.mode		= 0644,
6848 		.proc_handler	= proc_dointvec,
6849 	},
6850 	{
6851 		.procname	= "accept_ra_mtu",
6852 		.data		= &ipv6_devconf.accept_ra_mtu,
6853 		.maxlen		= sizeof(int),
6854 		.mode		= 0644,
6855 		.proc_handler	= proc_dointvec,
6856 	},
6857 	{
6858 		.procname	= "stable_secret",
6859 		.data		= &ipv6_devconf.stable_secret,
6860 		.maxlen		= IPV6_MAX_STRLEN,
6861 		.mode		= 0600,
6862 		.proc_handler	= addrconf_sysctl_stable_secret,
6863 	},
6864 	{
6865 		.procname	= "use_oif_addrs_only",
6866 		.data		= &ipv6_devconf.use_oif_addrs_only,
6867 		.maxlen		= sizeof(int),
6868 		.mode		= 0644,
6869 		.proc_handler	= proc_dointvec,
6870 	},
6871 	{
6872 		.procname	= "ignore_routes_with_linkdown",
6873 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6874 		.maxlen		= sizeof(int),
6875 		.mode		= 0644,
6876 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6877 	},
6878 	{
6879 		.procname	= "drop_unicast_in_l2_multicast",
6880 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6881 		.maxlen		= sizeof(int),
6882 		.mode		= 0644,
6883 		.proc_handler	= proc_dointvec,
6884 	},
6885 	{
6886 		.procname	= "drop_unsolicited_na",
6887 		.data		= &ipv6_devconf.drop_unsolicited_na,
6888 		.maxlen		= sizeof(int),
6889 		.mode		= 0644,
6890 		.proc_handler	= proc_dointvec,
6891 	},
6892 	{
6893 		.procname	= "keep_addr_on_down",
6894 		.data		= &ipv6_devconf.keep_addr_on_down,
6895 		.maxlen		= sizeof(int),
6896 		.mode		= 0644,
6897 		.proc_handler	= proc_dointvec,
6898 
6899 	},
6900 	{
6901 		.procname	= "seg6_enabled",
6902 		.data		= &ipv6_devconf.seg6_enabled,
6903 		.maxlen		= sizeof(int),
6904 		.mode		= 0644,
6905 		.proc_handler	= proc_dointvec,
6906 	},
6907 #ifdef CONFIG_IPV6_SEG6_HMAC
6908 	{
6909 		.procname	= "seg6_require_hmac",
6910 		.data		= &ipv6_devconf.seg6_require_hmac,
6911 		.maxlen		= sizeof(int),
6912 		.mode		= 0644,
6913 		.proc_handler	= proc_dointvec,
6914 	},
6915 #endif
6916 	{
6917 		.procname       = "enhanced_dad",
6918 		.data           = &ipv6_devconf.enhanced_dad,
6919 		.maxlen         = sizeof(int),
6920 		.mode           = 0644,
6921 		.proc_handler   = proc_dointvec,
6922 	},
6923 	{
6924 		.procname	= "addr_gen_mode",
6925 		.data		= &ipv6_devconf.addr_gen_mode,
6926 		.maxlen		= sizeof(int),
6927 		.mode		= 0644,
6928 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6929 	},
6930 	{
6931 		.procname       = "disable_policy",
6932 		.data           = &ipv6_devconf.disable_policy,
6933 		.maxlen         = sizeof(int),
6934 		.mode           = 0644,
6935 		.proc_handler   = addrconf_sysctl_disable_policy,
6936 	},
6937 	{
6938 		.procname	= "ndisc_tclass",
6939 		.data		= &ipv6_devconf.ndisc_tclass,
6940 		.maxlen		= sizeof(int),
6941 		.mode		= 0644,
6942 		.proc_handler	= proc_dointvec_minmax,
6943 		.extra1		= (void *)SYSCTL_ZERO,
6944 		.extra2		= (void *)&two_five_five,
6945 	},
6946 	{
6947 		.procname	= "rpl_seg_enabled",
6948 		.data		= &ipv6_devconf.rpl_seg_enabled,
6949 		.maxlen		= sizeof(int),
6950 		.mode		= 0644,
6951 		.proc_handler	= proc_dointvec,
6952 	},
6953 	{
6954 		.procname	= "ioam6_enabled",
6955 		.data		= &ipv6_devconf.ioam6_enabled,
6956 		.maxlen		= sizeof(u8),
6957 		.mode		= 0644,
6958 		.proc_handler	= proc_dou8vec_minmax,
6959 		.extra1		= (void *)SYSCTL_ZERO,
6960 		.extra2		= (void *)SYSCTL_ONE,
6961 	},
6962 	{
6963 		.procname	= "ioam6_id",
6964 		.data		= &ipv6_devconf.ioam6_id,
6965 		.maxlen		= sizeof(u32),
6966 		.mode		= 0644,
6967 		.proc_handler	= proc_douintvec_minmax,
6968 		.extra1		= (void *)SYSCTL_ZERO,
6969 		.extra2		= (void *)&ioam6_if_id_max,
6970 	},
6971 	{
6972 		.procname	= "ioam6_id_wide",
6973 		.data		= &ipv6_devconf.ioam6_id_wide,
6974 		.maxlen		= sizeof(u32),
6975 		.mode		= 0644,
6976 		.proc_handler	= proc_douintvec,
6977 	},
6978 	{
6979 		/* sentinel */
6980 	}
6981 };
6982 
6983 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6984 		struct inet6_dev *idev, struct ipv6_devconf *p)
6985 {
6986 	int i, ifindex;
6987 	struct ctl_table *table;
6988 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6989 
6990 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6991 	if (!table)
6992 		goto out;
6993 
6994 	for (i = 0; table[i].data; i++) {
6995 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6996 		/* If one of these is already set, then it is not safe to
6997 		 * overwrite either of them: this makes proc_dointvec_minmax
6998 		 * usable.
6999 		 */
7000 		if (!table[i].extra1 && !table[i].extra2) {
7001 			table[i].extra1 = idev; /* embedded; no ref */
7002 			table[i].extra2 = net;
7003 		}
7004 	}
7005 
7006 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7007 
7008 	p->sysctl_header = register_net_sysctl(net, path, table);
7009 	if (!p->sysctl_header)
7010 		goto free;
7011 
7012 	if (!strcmp(dev_name, "all"))
7013 		ifindex = NETCONFA_IFINDEX_ALL;
7014 	else if (!strcmp(dev_name, "default"))
7015 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7016 	else
7017 		ifindex = idev->dev->ifindex;
7018 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7019 				     ifindex, p);
7020 	return 0;
7021 
7022 free:
7023 	kfree(table);
7024 out:
7025 	return -ENOBUFS;
7026 }
7027 
7028 static void __addrconf_sysctl_unregister(struct net *net,
7029 					 struct ipv6_devconf *p, int ifindex)
7030 {
7031 	struct ctl_table *table;
7032 
7033 	if (!p->sysctl_header)
7034 		return;
7035 
7036 	table = p->sysctl_header->ctl_table_arg;
7037 	unregister_net_sysctl_table(p->sysctl_header);
7038 	p->sysctl_header = NULL;
7039 	kfree(table);
7040 
7041 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7042 }
7043 
7044 static int addrconf_sysctl_register(struct inet6_dev *idev)
7045 {
7046 	int err;
7047 
7048 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7049 		return -EINVAL;
7050 
7051 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7052 				    &ndisc_ifinfo_sysctl_change);
7053 	if (err)
7054 		return err;
7055 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7056 					 idev, &idev->cnf);
7057 	if (err)
7058 		neigh_sysctl_unregister(idev->nd_parms);
7059 
7060 	return err;
7061 }
7062 
7063 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7064 {
7065 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7066 				     idev->dev->ifindex);
7067 	neigh_sysctl_unregister(idev->nd_parms);
7068 }
7069 
7070 
7071 #endif
7072 
7073 static int __net_init addrconf_init_net(struct net *net)
7074 {
7075 	int err = -ENOMEM;
7076 	struct ipv6_devconf *all, *dflt;
7077 
7078 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7079 	if (!all)
7080 		goto err_alloc_all;
7081 
7082 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7083 	if (!dflt)
7084 		goto err_alloc_dflt;
7085 
7086 	if (IS_ENABLED(CONFIG_SYSCTL) &&
7087 	    !net_eq(net, &init_net)) {
7088 		switch (sysctl_devconf_inherit_init_net) {
7089 		case 1:  /* copy from init_net */
7090 			memcpy(all, init_net.ipv6.devconf_all,
7091 			       sizeof(ipv6_devconf));
7092 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7093 			       sizeof(ipv6_devconf_dflt));
7094 			break;
7095 		case 3: /* copy from the current netns */
7096 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7097 			       sizeof(ipv6_devconf));
7098 			memcpy(dflt,
7099 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7100 			       sizeof(ipv6_devconf_dflt));
7101 			break;
7102 		case 0:
7103 		case 2:
7104 			/* use compiled values */
7105 			break;
7106 		}
7107 	}
7108 
7109 	/* these will be inherited by all namespaces */
7110 	dflt->autoconf = ipv6_defaults.autoconf;
7111 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7112 
7113 	dflt->stable_secret.initialized = false;
7114 	all->stable_secret.initialized = false;
7115 
7116 	net->ipv6.devconf_all = all;
7117 	net->ipv6.devconf_dflt = dflt;
7118 
7119 #ifdef CONFIG_SYSCTL
7120 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7121 	if (err < 0)
7122 		goto err_reg_all;
7123 
7124 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7125 	if (err < 0)
7126 		goto err_reg_dflt;
7127 #endif
7128 	return 0;
7129 
7130 #ifdef CONFIG_SYSCTL
7131 err_reg_dflt:
7132 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7133 err_reg_all:
7134 	kfree(dflt);
7135 #endif
7136 err_alloc_dflt:
7137 	kfree(all);
7138 err_alloc_all:
7139 	return err;
7140 }
7141 
7142 static void __net_exit addrconf_exit_net(struct net *net)
7143 {
7144 #ifdef CONFIG_SYSCTL
7145 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7146 				     NETCONFA_IFINDEX_DEFAULT);
7147 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7148 				     NETCONFA_IFINDEX_ALL);
7149 #endif
7150 	kfree(net->ipv6.devconf_dflt);
7151 	kfree(net->ipv6.devconf_all);
7152 }
7153 
7154 static struct pernet_operations addrconf_ops = {
7155 	.init = addrconf_init_net,
7156 	.exit = addrconf_exit_net,
7157 };
7158 
7159 static struct rtnl_af_ops inet6_ops __read_mostly = {
7160 	.family		  = AF_INET6,
7161 	.fill_link_af	  = inet6_fill_link_af,
7162 	.get_link_af_size = inet6_get_link_af_size,
7163 	.validate_link_af = inet6_validate_link_af,
7164 	.set_link_af	  = inet6_set_link_af,
7165 };
7166 
7167 /*
7168  *	Init / cleanup code
7169  */
7170 
7171 int __init addrconf_init(void)
7172 {
7173 	struct inet6_dev *idev;
7174 	int i, err;
7175 
7176 	err = ipv6_addr_label_init();
7177 	if (err < 0) {
7178 		pr_crit("%s: cannot initialize default policy table: %d\n",
7179 			__func__, err);
7180 		goto out;
7181 	}
7182 
7183 	err = register_pernet_subsys(&addrconf_ops);
7184 	if (err < 0)
7185 		goto out_addrlabel;
7186 
7187 	addrconf_wq = create_workqueue("ipv6_addrconf");
7188 	if (!addrconf_wq) {
7189 		err = -ENOMEM;
7190 		goto out_nowq;
7191 	}
7192 
7193 	/* The addrconf netdev notifier requires that loopback_dev
7194 	 * has it's ipv6 private information allocated and setup
7195 	 * before it can bring up and give link-local addresses
7196 	 * to other devices which are up.
7197 	 *
7198 	 * Unfortunately, loopback_dev is not necessarily the first
7199 	 * entry in the global dev_base list of net devices.  In fact,
7200 	 * it is likely to be the very last entry on that list.
7201 	 * So this causes the notifier registry below to try and
7202 	 * give link-local addresses to all devices besides loopback_dev
7203 	 * first, then loopback_dev, which cases all the non-loopback_dev
7204 	 * devices to fail to get a link-local address.
7205 	 *
7206 	 * So, as a temporary fix, allocate the ipv6 structure for
7207 	 * loopback_dev first by hand.
7208 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7209 	 * device and it being up should be removed.
7210 	 */
7211 	rtnl_lock();
7212 	idev = ipv6_add_dev(init_net.loopback_dev);
7213 	rtnl_unlock();
7214 	if (IS_ERR(idev)) {
7215 		err = PTR_ERR(idev);
7216 		goto errlo;
7217 	}
7218 
7219 	ip6_route_init_special_entries();
7220 
7221 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7222 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7223 
7224 	register_netdevice_notifier(&ipv6_dev_notf);
7225 
7226 	addrconf_verify();
7227 
7228 	rtnl_af_register(&inet6_ops);
7229 
7230 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7231 				   NULL, inet6_dump_ifinfo, 0);
7232 	if (err < 0)
7233 		goto errout;
7234 
7235 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7236 				   inet6_rtm_newaddr, NULL, 0);
7237 	if (err < 0)
7238 		goto errout;
7239 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7240 				   inet6_rtm_deladdr, NULL, 0);
7241 	if (err < 0)
7242 		goto errout;
7243 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7244 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7245 				   RTNL_FLAG_DOIT_UNLOCKED);
7246 	if (err < 0)
7247 		goto errout;
7248 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7249 				   NULL, inet6_dump_ifmcaddr, 0);
7250 	if (err < 0)
7251 		goto errout;
7252 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7253 				   NULL, inet6_dump_ifacaddr, 0);
7254 	if (err < 0)
7255 		goto errout;
7256 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7257 				   inet6_netconf_get_devconf,
7258 				   inet6_netconf_dump_devconf,
7259 				   RTNL_FLAG_DOIT_UNLOCKED);
7260 	if (err < 0)
7261 		goto errout;
7262 	err = ipv6_addr_label_rtnl_register();
7263 	if (err < 0)
7264 		goto errout;
7265 
7266 	return 0;
7267 errout:
7268 	rtnl_unregister_all(PF_INET6);
7269 	rtnl_af_unregister(&inet6_ops);
7270 	unregister_netdevice_notifier(&ipv6_dev_notf);
7271 errlo:
7272 	destroy_workqueue(addrconf_wq);
7273 out_nowq:
7274 	unregister_pernet_subsys(&addrconf_ops);
7275 out_addrlabel:
7276 	ipv6_addr_label_cleanup();
7277 out:
7278 	return err;
7279 }
7280 
7281 void addrconf_cleanup(void)
7282 {
7283 	struct net_device *dev;
7284 	int i;
7285 
7286 	unregister_netdevice_notifier(&ipv6_dev_notf);
7287 	unregister_pernet_subsys(&addrconf_ops);
7288 	ipv6_addr_label_cleanup();
7289 
7290 	rtnl_af_unregister(&inet6_ops);
7291 
7292 	rtnl_lock();
7293 
7294 	/* clean dev list */
7295 	for_each_netdev(&init_net, dev) {
7296 		if (__in6_dev_get(dev) == NULL)
7297 			continue;
7298 		addrconf_ifdown(dev, true);
7299 	}
7300 	addrconf_ifdown(init_net.loopback_dev, true);
7301 
7302 	/*
7303 	 *	Check hash table.
7304 	 */
7305 	spin_lock_bh(&addrconf_hash_lock);
7306 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7307 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7308 	spin_unlock_bh(&addrconf_hash_lock);
7309 	cancel_delayed_work(&addr_chk_work);
7310 	rtnl_unlock();
7311 
7312 	destroy_workqueue(addrconf_wq);
7313 }
7314