xref: /linux/net/ipv6/addrconf.c (revision 17dc3b245de45b1f2012e3a48ec51889f544e67b)
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 <crypto/sha1.h>
40 #include <linux/errno.h>
41 #include <linux/types.h>
42 #include <linux/kernel.h>
43 #include <linux/sched/signal.h>
44 #include <linux/socket.h>
45 #include <linux/sockios.h>
46 #include <linux/net.h>
47 #include <linux/inet.h>
48 #include <linux/in6.h>
49 #include <linux/netdevice.h>
50 #include <linux/if_addr.h>
51 #include <linux/if_arp.h>
52 #include <linux/if_arcnet.h>
53 #include <linux/if_infiniband.h>
54 #include <linux/route.h>
55 #include <linux/inetdevice.h>
56 #include <linux/init.h>
57 #include <linux/slab.h>
58 #ifdef CONFIG_SYSCTL
59 #include <linux/sysctl.h>
60 #endif
61 #include <linux/capability.h>
62 #include <linux/delay.h>
63 #include <linux/notifier.h>
64 #include <linux/string.h>
65 #include <linux/hash.h>
66 
67 #include <net/ip_tunnels.h>
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/6lowpan.h>
73 #include <net/firewire.h>
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/tcp.h>
80 #include <net/ip.h>
81 #include <net/netlink.h>
82 #include <net/pkt_sched.h>
83 #include <net/l3mdev.h>
84 #include <net/netdev_lock.h>
85 #include <linux/if_tunnel.h>
86 #include <linux/rtnetlink.h>
87 #include <linux/netconf.h>
88 #include <linux/random.h>
89 #include <linux/uaccess.h>
90 #include <linux/unaligned.h>
91 
92 #include <linux/proc_fs.h>
93 #include <linux/seq_file.h>
94 #include <linux/export.h>
95 #include <linux/ioam6.h>
96 
97 #define IPV6_MAX_STRLEN \
98 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
99 
100 static inline u32 cstamp_delta(unsigned long cstamp)
101 {
102 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
103 }
104 
105 static inline s32 rfc3315_s14_backoff_init(s32 irt)
106 {
107 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
108 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
109 	do_div(tmp, 1000000);
110 	return (s32)tmp;
111 }
112 
113 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
114 {
115 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
116 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
117 	do_div(tmp, 1000000);
118 	if ((s32)tmp > mrt) {
119 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
120 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
121 		do_div(tmp, 1000000);
122 	}
123 	return (s32)tmp;
124 }
125 
126 #ifdef CONFIG_SYSCTL
127 static int addrconf_sysctl_register(struct inet6_dev *idev);
128 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
129 #else
130 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
131 {
132 	return 0;
133 }
134 
135 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
136 {
137 }
138 #endif
139 
140 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
141 
142 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
143 static int ipv6_count_addresses(const struct inet6_dev *idev);
144 static int ipv6_generate_stable_address(struct in6_addr *addr,
145 					u8 dad_count,
146 					const struct inet6_dev *idev);
147 
148 #define IN6_ADDR_HSIZE_SHIFT	8
149 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
150 
151 static void addrconf_verify(struct net *net);
152 static void addrconf_verify_rtnl(struct net *net);
153 
154 static struct workqueue_struct *addrconf_wq;
155 
156 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
157 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
158 
159 static void addrconf_type_change(struct net_device *dev,
160 				 unsigned long event);
161 static int addrconf_ifdown(struct net_device *dev, bool unregister);
162 
163 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
164 						  int plen,
165 						  const struct net_device *dev,
166 						  u32 flags, u32 noflags,
167 						  bool no_gw);
168 
169 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
170 static void addrconf_dad_work(struct work_struct *w);
171 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
172 				   bool send_na);
173 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
174 static void addrconf_rs_timer(struct timer_list *t);
175 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
176 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
177 
178 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
179 				struct prefix_info *pinfo);
180 
181 static struct ipv6_devconf ipv6_devconf __read_mostly = {
182 	.forwarding		= 0,
183 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
184 	.mtu6			= IPV6_MIN_MTU,
185 	.accept_ra		= 1,
186 	.accept_redirects	= 1,
187 	.autoconf		= 1,
188 	.force_mld_version	= 0,
189 	.mldv1_unsolicited_report_interval = 10 * HZ,
190 	.mldv2_unsolicited_report_interval = HZ,
191 	.dad_transmits		= 1,
192 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
193 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
194 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
195 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
196 	.use_tempaddr		= 0,
197 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
198 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
199 	.regen_min_advance	= REGEN_MIN_ADVANCE,
200 	.regen_max_retry	= REGEN_MAX_RETRY,
201 	.max_desync_factor	= MAX_DESYNC_FACTOR,
202 	.max_addresses		= IPV6_MAX_ADDRESSES,
203 	.accept_ra_defrtr	= 1,
204 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
205 	.accept_ra_from_local	= 0,
206 	.accept_ra_min_hop_limit= 1,
207 	.accept_ra_min_lft	= 0,
208 	.accept_ra_pinfo	= 1,
209 #ifdef CONFIG_IPV6_ROUTER_PREF
210 	.accept_ra_rtr_pref	= 1,
211 	.rtr_probe_interval	= 60 * HZ,
212 #ifdef CONFIG_IPV6_ROUTE_INFO
213 	.accept_ra_rt_info_min_plen = 0,
214 	.accept_ra_rt_info_max_plen = 0,
215 #endif
216 #endif
217 	.proxy_ndp		= 0,
218 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
219 	.disable_ipv6		= 0,
220 	.accept_dad		= 0,
221 	.suppress_frag_ndisc	= 1,
222 	.accept_ra_mtu		= 1,
223 	.stable_secret		= {
224 		.initialized = false,
225 	},
226 	.use_oif_addrs_only	= 0,
227 	.ignore_routes_with_linkdown = 0,
228 	.keep_addr_on_down	= 0,
229 	.seg6_enabled		= 0,
230 #ifdef CONFIG_IPV6_SEG6_HMAC
231 	.seg6_require_hmac	= 0,
232 #endif
233 	.enhanced_dad           = 1,
234 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
235 	.disable_policy		= 0,
236 	.rpl_seg_enabled	= 0,
237 	.ioam6_enabled		= 0,
238 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
239 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
240 	.ndisc_evict_nocarrier	= 1,
241 	.ra_honor_pio_life	= 0,
242 	.ra_honor_pio_pflag	= 0,
243 	.force_forwarding	= 0,
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_min_advance	= REGEN_MIN_ADVANCE,
265 	.regen_max_retry	= REGEN_MAX_RETRY,
266 	.max_desync_factor	= MAX_DESYNC_FACTOR,
267 	.max_addresses		= IPV6_MAX_ADDRESSES,
268 	.accept_ra_defrtr	= 1,
269 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
270 	.accept_ra_from_local	= 0,
271 	.accept_ra_min_hop_limit= 1,
272 	.accept_ra_min_lft	= 0,
273 	.accept_ra_pinfo	= 1,
274 #ifdef CONFIG_IPV6_ROUTER_PREF
275 	.accept_ra_rtr_pref	= 1,
276 	.rtr_probe_interval	= 60 * HZ,
277 #ifdef CONFIG_IPV6_ROUTE_INFO
278 	.accept_ra_rt_info_min_plen = 0,
279 	.accept_ra_rt_info_max_plen = 0,
280 #endif
281 #endif
282 	.proxy_ndp		= 0,
283 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
284 	.disable_ipv6		= 0,
285 	.accept_dad		= 1,
286 	.suppress_frag_ndisc	= 1,
287 	.accept_ra_mtu		= 1,
288 	.stable_secret		= {
289 		.initialized = false,
290 	},
291 	.use_oif_addrs_only	= 0,
292 	.ignore_routes_with_linkdown = 0,
293 	.keep_addr_on_down	= 0,
294 	.seg6_enabled		= 0,
295 #ifdef CONFIG_IPV6_SEG6_HMAC
296 	.seg6_require_hmac	= 0,
297 #endif
298 	.enhanced_dad           = 1,
299 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
300 	.disable_policy		= 0,
301 	.rpl_seg_enabled	= 0,
302 	.ioam6_enabled		= 0,
303 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
304 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
305 	.ndisc_evict_nocarrier	= 1,
306 	.ra_honor_pio_life	= 0,
307 	.ra_honor_pio_pflag	= 0,
308 	.force_forwarding	= 0,
309 };
310 
311 /* Check if link is ready: is it up and is a valid qdisc available */
312 static inline bool addrconf_link_ready(const struct net_device *dev)
313 {
314 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
315 }
316 
317 static void addrconf_del_rs_timer(struct inet6_dev *idev)
318 {
319 	if (timer_delete(&idev->rs_timer))
320 		__in6_dev_put(idev);
321 }
322 
323 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
324 {
325 	if (cancel_delayed_work(&ifp->dad_work))
326 		__in6_ifa_put(ifp);
327 }
328 
329 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
330 				  unsigned long when)
331 {
332 	if (!mod_timer(&idev->rs_timer, jiffies + when))
333 		in6_dev_hold(idev);
334 }
335 
336 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
337 				   unsigned long delay)
338 {
339 	in6_ifa_hold(ifp);
340 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
341 		in6_ifa_put(ifp);
342 }
343 
344 static int snmp6_alloc_dev(struct inet6_dev *idev)
345 {
346 	int i;
347 
348 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
349 	if (!idev->stats.ipv6)
350 		goto err_ip;
351 
352 	for_each_possible_cpu(i) {
353 		struct ipstats_mib *addrconf_stats;
354 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
355 		u64_stats_init(&addrconf_stats->syncp);
356 	}
357 
358 
359 	idev->stats.icmpv6dev = kzalloc_obj(struct icmpv6_mib_device);
360 	if (!idev->stats.icmpv6dev)
361 		goto err_icmp;
362 	idev->stats.icmpv6msgdev = kzalloc_obj(struct icmpv6msg_mib_device,
363 					       GFP_KERNEL_ACCOUNT);
364 	if (!idev->stats.icmpv6msgdev)
365 		goto err_icmpmsg;
366 
367 	return 0;
368 
369 err_icmpmsg:
370 	kfree(idev->stats.icmpv6dev);
371 err_icmp:
372 	free_percpu(idev->stats.ipv6);
373 err_ip:
374 	return -ENOMEM;
375 }
376 
377 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
378 {
379 	struct inet6_dev *ndev;
380 	int err = -ENOMEM;
381 
382 	ASSERT_RTNL();
383 	netdev_assert_locked_ops_compat(dev);
384 
385 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
386 		return ERR_PTR(-EINVAL);
387 
388 	ndev = kzalloc_obj(*ndev, GFP_KERNEL_ACCOUNT);
389 	if (!ndev)
390 		return ERR_PTR(err);
391 
392 	rwlock_init(&ndev->lock);
393 	ndev->dev = dev;
394 	INIT_LIST_HEAD(&ndev->addr_list);
395 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
396 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
397 
398 	if (ndev->cnf.stable_secret.initialized)
399 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
400 
401 	ndev->cnf.mtu6 = dev->mtu;
402 	ndev->ra_mtu = 0;
403 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
404 	if (!ndev->nd_parms) {
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 	if (ndev->cnf.forwarding)
409 		netif_disable_lro(dev);
410 	/* We refer to the device */
411 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
412 
413 	if (snmp6_alloc_dev(ndev) < 0) {
414 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
415 			   __func__);
416 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
417 		netdev_put(dev, &ndev->dev_tracker);
418 		kfree(ndev);
419 		return ERR_PTR(err);
420 	}
421 
422 	if (dev != blackhole_netdev) {
423 		if (snmp6_register_dev(ndev) < 0) {
424 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
425 				   __func__, dev->name);
426 			goto err_release;
427 		}
428 	}
429 	/* One reference from device. */
430 	refcount_set(&ndev->refcnt, 1);
431 
432 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
433 		ndev->cnf.accept_dad = -1;
434 
435 #if IS_ENABLED(CONFIG_IPV6_SIT)
436 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
437 		pr_info("%s: Disabled Multicast RS\n", dev->name);
438 		ndev->cnf.rtr_solicits = 0;
439 	}
440 #endif
441 
442 	INIT_LIST_HEAD(&ndev->tempaddr_list);
443 	ndev->desync_factor = U32_MAX;
444 	if ((dev->flags&IFF_LOOPBACK) ||
445 	    dev->type == ARPHRD_TUNNEL ||
446 	    dev->type == ARPHRD_TUNNEL6 ||
447 	    dev->type == ARPHRD_SIT ||
448 	    dev->type == ARPHRD_NONE) {
449 		ndev->cnf.use_tempaddr = -1;
450 	}
451 
452 	ndev->token = in6addr_any;
453 
454 	if (netif_running(dev) && addrconf_link_ready(dev))
455 		ndev->if_flags |= IF_READY;
456 
457 	ipv6_mc_init_dev(ndev);
458 	ndev->tstamp = jiffies;
459 	if (dev != blackhole_netdev) {
460 		err = addrconf_sysctl_register(ndev);
461 		if (err) {
462 			ipv6_mc_destroy_dev(ndev);
463 			snmp6_unregister_dev(ndev);
464 			goto err_release;
465 		}
466 	}
467 	/* protected by rtnl_lock */
468 	rcu_assign_pointer(dev->ip6_ptr, ndev);
469 
470 	if (dev != blackhole_netdev) {
471 		/* Join interface-local all-node multicast group */
472 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
473 
474 		/* Join all-node multicast group */
475 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
476 
477 		/* Join all-router multicast group if forwarding is set */
478 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
479 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
480 	}
481 	return ndev;
482 
483 err_release:
484 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
485 	ndev->dead = 1;
486 	in6_dev_finish_destroy(ndev);
487 	return ERR_PTR(err);
488 }
489 
490 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
491 {
492 	struct inet6_dev *idev;
493 
494 	ASSERT_RTNL();
495 
496 	idev = __in6_dev_get(dev);
497 	if (!idev) {
498 		idev = ipv6_add_dev(dev);
499 		if (IS_ERR(idev))
500 			return idev;
501 	}
502 
503 	if (dev->flags&IFF_UP)
504 		ipv6_mc_up(idev);
505 	return idev;
506 }
507 
508 static int inet6_netconf_msgsize_devconf(int type)
509 {
510 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
511 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
512 	bool all = false;
513 
514 	if (type == NETCONFA_ALL)
515 		all = true;
516 
517 	if (all || type == NETCONFA_FORWARDING)
518 		size += nla_total_size(4);
519 #ifdef CONFIG_IPV6_MROUTE
520 	if (all || type == NETCONFA_MC_FORWARDING)
521 		size += nla_total_size(4);
522 #endif
523 	if (all || type == NETCONFA_PROXY_NEIGH)
524 		size += nla_total_size(4);
525 
526 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
527 		size += nla_total_size(4);
528 
529 	return size;
530 }
531 
532 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
533 				      struct ipv6_devconf *devconf, u32 portid,
534 				      u32 seq, int event, unsigned int flags,
535 				      int type)
536 {
537 	struct nlmsghdr  *nlh;
538 	struct netconfmsg *ncm;
539 	bool all = false;
540 
541 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
542 			flags);
543 	if (!nlh)
544 		return -EMSGSIZE;
545 
546 	if (type == NETCONFA_ALL)
547 		all = true;
548 
549 	ncm = nlmsg_data(nlh);
550 	ncm->ncm_family = AF_INET6;
551 
552 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
553 		goto nla_put_failure;
554 
555 	if (!devconf)
556 		goto out;
557 
558 	if ((all || type == NETCONFA_FORWARDING) &&
559 	    nla_put_s32(skb, NETCONFA_FORWARDING,
560 			READ_ONCE(devconf->forwarding)) < 0)
561 		goto nla_put_failure;
562 #ifdef CONFIG_IPV6_MROUTE
563 	if ((all || type == NETCONFA_MC_FORWARDING) &&
564 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
565 			atomic_read(&devconf->mc_forwarding)) < 0)
566 		goto nla_put_failure;
567 #endif
568 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
569 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
570 			READ_ONCE(devconf->proxy_ndp)) < 0)
571 		goto nla_put_failure;
572 
573 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
574 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
575 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
576 		goto nla_put_failure;
577 
578 out:
579 	nlmsg_end(skb, nlh);
580 	return 0;
581 
582 nla_put_failure:
583 	nlmsg_cancel(skb, nlh);
584 	return -EMSGSIZE;
585 }
586 
587 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
588 				  int ifindex, struct ipv6_devconf *devconf)
589 {
590 	struct sk_buff *skb;
591 	int err = -ENOBUFS;
592 
593 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
594 	if (!skb)
595 		goto errout;
596 
597 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
598 					 event, 0, type);
599 	if (err < 0) {
600 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
601 		WARN_ON(err == -EMSGSIZE);
602 		kfree_skb(skb);
603 		goto errout;
604 	}
605 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
606 	return;
607 errout:
608 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
609 }
610 
611 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
612 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
613 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
614 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
615 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
616 };
617 
618 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
619 				       const struct nlmsghdr *nlh,
620 				       struct nlattr **tb,
621 				       struct netlink_ext_ack *extack)
622 {
623 	int i, err;
624 
625 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
626 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
627 		return -EINVAL;
628 	}
629 
630 	if (!netlink_strict_get_check(skb))
631 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
632 					      tb, NETCONFA_MAX,
633 					      devconf_ipv6_policy, extack);
634 
635 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
636 					    tb, NETCONFA_MAX,
637 					    devconf_ipv6_policy, extack);
638 	if (err)
639 		return err;
640 
641 	for (i = 0; i <= NETCONFA_MAX; i++) {
642 		if (!tb[i])
643 			continue;
644 
645 		switch (i) {
646 		case NETCONFA_IFINDEX:
647 			break;
648 		default:
649 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
650 			return -EINVAL;
651 		}
652 	}
653 
654 	return 0;
655 }
656 
657 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
658 				     struct nlmsghdr *nlh,
659 				     struct netlink_ext_ack *extack)
660 {
661 	struct net *net = sock_net(in_skb->sk);
662 	struct nlattr *tb[NETCONFA_MAX+1];
663 	struct inet6_dev *in6_dev = NULL;
664 	struct net_device *dev = NULL;
665 	struct sk_buff *skb;
666 	struct ipv6_devconf *devconf;
667 	int ifindex;
668 	int err;
669 
670 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
671 	if (err < 0)
672 		return err;
673 
674 	if (!tb[NETCONFA_IFINDEX])
675 		return -EINVAL;
676 
677 	err = -EINVAL;
678 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
679 	switch (ifindex) {
680 	case NETCONFA_IFINDEX_ALL:
681 		devconf = net->ipv6.devconf_all;
682 		break;
683 	case NETCONFA_IFINDEX_DEFAULT:
684 		devconf = net->ipv6.devconf_dflt;
685 		break;
686 	default:
687 		dev = dev_get_by_index(net, ifindex);
688 		if (!dev)
689 			return -EINVAL;
690 		in6_dev = in6_dev_get(dev);
691 		if (!in6_dev)
692 			goto errout;
693 		devconf = &in6_dev->cnf;
694 		break;
695 	}
696 
697 	err = -ENOBUFS;
698 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
699 	if (!skb)
700 		goto errout;
701 
702 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
703 					 NETLINK_CB(in_skb).portid,
704 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
705 					 NETCONFA_ALL);
706 	if (err < 0) {
707 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
708 		WARN_ON(err == -EMSGSIZE);
709 		kfree_skb(skb);
710 		goto errout;
711 	}
712 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
713 errout:
714 	if (in6_dev)
715 		in6_dev_put(in6_dev);
716 	dev_put(dev);
717 	return err;
718 }
719 
720 /* Combine dev_addr_genid and dev_base_seq to detect changes.
721  */
722 static u32 inet6_base_seq(const struct net *net)
723 {
724 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
725 		  READ_ONCE(net->dev_base_seq);
726 
727 	/* Must not return 0 (see nl_dump_check_consistent()).
728 	 * Chose a value far away from 0.
729 	 */
730 	if (!res)
731 		res = 0x80000000;
732 	return res;
733 }
734 
735 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
736 				      struct netlink_callback *cb)
737 {
738 	const struct nlmsghdr *nlh = cb->nlh;
739 	struct net *net = sock_net(skb->sk);
740 	struct {
741 		unsigned long ifindex;
742 		unsigned int all_default;
743 	} *ctx = (void *)cb->ctx;
744 	struct net_device *dev;
745 	struct inet6_dev *idev;
746 	int err = 0;
747 
748 	if (cb->strict_check) {
749 		struct netlink_ext_ack *extack = cb->extack;
750 		struct netconfmsg *ncm;
751 
752 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
753 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
754 			return -EINVAL;
755 		}
756 
757 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
758 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
759 			return -EINVAL;
760 		}
761 	}
762 
763 	rcu_read_lock();
764 	for_each_netdev_dump(net, dev, ctx->ifindex) {
765 		idev = __in6_dev_get(dev);
766 		if (!idev)
767 			continue;
768 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
769 					         &idev->cnf,
770 						 NETLINK_CB(cb->skb).portid,
771 						 nlh->nlmsg_seq,
772 						 RTM_NEWNETCONF,
773 						 NLM_F_MULTI,
774 						 NETCONFA_ALL);
775 		if (err < 0)
776 			goto done;
777 	}
778 	if (ctx->all_default == 0) {
779 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
780 						 net->ipv6.devconf_all,
781 						 NETLINK_CB(cb->skb).portid,
782 						 nlh->nlmsg_seq,
783 						 RTM_NEWNETCONF, NLM_F_MULTI,
784 						 NETCONFA_ALL);
785 		if (err < 0)
786 			goto done;
787 		ctx->all_default++;
788 	}
789 	if (ctx->all_default == 1) {
790 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
791 						 net->ipv6.devconf_dflt,
792 						 NETLINK_CB(cb->skb).portid,
793 						 nlh->nlmsg_seq,
794 						 RTM_NEWNETCONF, NLM_F_MULTI,
795 						 NETCONFA_ALL);
796 		if (err < 0)
797 			goto done;
798 		ctx->all_default++;
799 	}
800 done:
801 	rcu_read_unlock();
802 	return err;
803 }
804 
805 #ifdef CONFIG_SYSCTL
806 static void dev_forward_change(struct inet6_dev *idev)
807 {
808 	struct net_device *dev;
809 	struct inet6_ifaddr *ifa;
810 	LIST_HEAD(tmp_addr_list);
811 
812 	if (!idev)
813 		return;
814 	dev = idev->dev;
815 	if (idev->cnf.forwarding)
816 		dev_disable_lro(dev);
817 	if (dev->flags & IFF_MULTICAST) {
818 		if (idev->cnf.forwarding) {
819 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
820 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
821 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
822 		} else {
823 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
824 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
825 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
826 		}
827 	}
828 
829 	read_lock_bh(&idev->lock);
830 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
831 		if (ifa->flags&IFA_F_TENTATIVE)
832 			continue;
833 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
834 	}
835 	read_unlock_bh(&idev->lock);
836 
837 	while (!list_empty(&tmp_addr_list)) {
838 		ifa = list_first_entry(&tmp_addr_list,
839 				       struct inet6_ifaddr, if_list_aux);
840 		list_del(&ifa->if_list_aux);
841 		if (idev->cnf.forwarding)
842 			addrconf_join_anycast(ifa);
843 		else
844 			addrconf_leave_anycast(ifa);
845 	}
846 
847 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
848 				     NETCONFA_FORWARDING,
849 				     dev->ifindex, &idev->cnf);
850 }
851 
852 
853 static void addrconf_forward_change(struct net *net, __s32 newf)
854 {
855 	struct net_device *dev;
856 	struct inet6_dev *idev;
857 
858 	for_each_netdev(net, dev) {
859 		idev = __in6_dev_get_rtnl_net(dev);
860 		if (idev) {
861 			int changed = (!idev->cnf.forwarding) ^ (!newf);
862 			/* Disabling all.forwarding sets 0 to force_forwarding for all interfaces */
863 			if (newf == 0)
864 				WRITE_ONCE(idev->cnf.force_forwarding, 0);
865 
866 			WRITE_ONCE(idev->cnf.forwarding, newf);
867 			if (changed)
868 				dev_forward_change(idev);
869 		}
870 	}
871 }
872 
873 static int addrconf_fixup_forwarding(const struct ctl_table *table, int *p, int newf)
874 {
875 	struct net *net = (struct net *)table->extra2;
876 	int old;
877 
878 	if (!rtnl_net_trylock(net))
879 		return restart_syscall();
880 
881 	old = *p;
882 	WRITE_ONCE(*p, newf);
883 
884 	if (p == &net->ipv6.devconf_dflt->forwarding) {
885 		if ((!newf) ^ (!old))
886 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
887 						     NETCONFA_FORWARDING,
888 						     NETCONFA_IFINDEX_DEFAULT,
889 						     net->ipv6.devconf_dflt);
890 		rtnl_net_unlock(net);
891 		return 0;
892 	}
893 
894 	if (p == &net->ipv6.devconf_all->forwarding) {
895 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
896 
897 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
898 		if ((!newf) ^ (!old_dflt))
899 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
900 						     NETCONFA_FORWARDING,
901 						     NETCONFA_IFINDEX_DEFAULT,
902 						     net->ipv6.devconf_dflt);
903 
904 		addrconf_forward_change(net, newf);
905 		if ((!newf) ^ (!old))
906 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
907 						     NETCONFA_FORWARDING,
908 						     NETCONFA_IFINDEX_ALL,
909 						     net->ipv6.devconf_all);
910 	} else if ((!newf) ^ (!old))
911 		dev_forward_change((struct inet6_dev *)table->extra1);
912 	rtnl_net_unlock(net);
913 
914 	if (newf)
915 		rt6_purge_dflt_routers(net);
916 	return 0;
917 }
918 
919 static void addrconf_linkdown_change(struct net *net, __s32 newf)
920 {
921 	struct net_device *dev;
922 	struct inet6_dev *idev;
923 
924 	for_each_netdev(net, dev) {
925 		idev = __in6_dev_get_rtnl_net(dev);
926 		if (idev) {
927 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
928 
929 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
930 			if (changed)
931 				inet6_netconf_notify_devconf(dev_net(dev),
932 							     RTM_NEWNETCONF,
933 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
934 							     dev->ifindex,
935 							     &idev->cnf);
936 		}
937 	}
938 }
939 
940 static int addrconf_fixup_linkdown(const struct ctl_table *table, int *p, int newf)
941 {
942 	struct net *net = (struct net *)table->extra2;
943 	int old;
944 
945 	if (!rtnl_net_trylock(net))
946 		return restart_syscall();
947 
948 	old = *p;
949 	WRITE_ONCE(*p, newf);
950 
951 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
952 		if ((!newf) ^ (!old))
953 			inet6_netconf_notify_devconf(net,
954 						     RTM_NEWNETCONF,
955 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
956 						     NETCONFA_IFINDEX_DEFAULT,
957 						     net->ipv6.devconf_dflt);
958 	} else if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
959 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
960 		addrconf_linkdown_change(net, newf);
961 		if ((!newf) ^ (!old))
962 			inet6_netconf_notify_devconf(net,
963 						     RTM_NEWNETCONF,
964 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
965 						     NETCONFA_IFINDEX_ALL,
966 						     net->ipv6.devconf_all);
967 	} else {
968 		if (!newf ^ !old) {
969 			struct inet6_dev *idev = table->extra1;
970 
971 			inet6_netconf_notify_devconf(net,
972 						     RTM_NEWNETCONF,
973 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
974 						     idev->dev->ifindex,
975 						     &idev->cnf);
976 		}
977 	}
978 
979 	rtnl_net_unlock(net);
980 
981 	return 0;
982 }
983 
984 #endif
985 
986 /* Nobody refers to this ifaddr, destroy it */
987 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
988 {
989 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
990 
991 #ifdef NET_REFCNT_DEBUG
992 	pr_debug("%s\n", __func__);
993 #endif
994 
995 	in6_dev_put(ifp->idev);
996 
997 	if (cancel_delayed_work(&ifp->dad_work))
998 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
999 			  ifp);
1000 
1001 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
1002 		pr_warn("Freeing alive inet6 address %p\n", ifp);
1003 		return;
1004 	}
1005 
1006 	kfree_rcu(ifp, rcu);
1007 }
1008 
1009 static void
1010 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
1011 {
1012 	struct list_head *p;
1013 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1014 
1015 	/*
1016 	 * Each device address list is sorted in order of scope -
1017 	 * global before linklocal.
1018 	 */
1019 	list_for_each(p, &idev->addr_list) {
1020 		struct inet6_ifaddr *ifa
1021 			= list_entry(p, struct inet6_ifaddr, if_list);
1022 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1023 			break;
1024 	}
1025 
1026 	list_add_tail_rcu(&ifp->if_list, p);
1027 }
1028 
1029 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1030 {
1031 	u32 val = __ipv6_addr_jhash(addr, net_hash_mix(net));
1032 
1033 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1034 }
1035 
1036 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1037 			       struct net_device *dev, unsigned int hash)
1038 {
1039 	struct inet6_ifaddr *ifp;
1040 
1041 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1042 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1043 			if (!dev || ifp->idev->dev == dev)
1044 				return true;
1045 		}
1046 	}
1047 	return false;
1048 }
1049 
1050 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1051 {
1052 	struct net *net = dev_net(dev);
1053 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1054 	int err = 0;
1055 
1056 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1057 
1058 	/* Ignore adding duplicate addresses on an interface */
1059 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1060 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1061 		err = -EEXIST;
1062 	} else {
1063 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1064 	}
1065 
1066 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1067 
1068 	return err;
1069 }
1070 
1071 /* On success it returns ifp with increased reference count */
1072 
1073 static struct inet6_ifaddr *
1074 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1075 	      bool can_block, struct netlink_ext_ack *extack)
1076 {
1077 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1078 	int addr_type = ipv6_addr_type(cfg->pfx);
1079 	struct net *net = dev_net(idev->dev);
1080 	struct inet6_ifaddr *ifa = NULL;
1081 	struct fib6_info *f6i = NULL;
1082 	int err = 0;
1083 
1084 	if (addr_type == IPV6_ADDR_ANY) {
1085 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1086 		return ERR_PTR(-EADDRNOTAVAIL);
1087 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1088 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1089 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1090 		return ERR_PTR(-EADDRNOTAVAIL);
1091 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1092 		   !netif_is_l3_master(idev->dev) &&
1093 		   addr_type & IPV6_ADDR_LOOPBACK) {
1094 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1095 		return ERR_PTR(-EADDRNOTAVAIL);
1096 	}
1097 
1098 	if (idev->dead) {
1099 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1100 		err = -ENODEV;
1101 		goto out;
1102 	}
1103 
1104 	if (idev->cnf.disable_ipv6) {
1105 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1106 		err = -EACCES;
1107 		goto out;
1108 	}
1109 
1110 	/* validator notifier needs to be blocking;
1111 	 * do not call in atomic context
1112 	 */
1113 	if (can_block) {
1114 		struct in6_validator_info i6vi = {
1115 			.i6vi_addr = *cfg->pfx,
1116 			.i6vi_dev = idev,
1117 			.extack = extack,
1118 		};
1119 
1120 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1121 		err = notifier_to_errno(err);
1122 		if (err < 0)
1123 			goto out;
1124 	}
1125 
1126 	ifa = kzalloc_obj(*ifa, gfp_flags | __GFP_ACCOUNT);
1127 	if (!ifa) {
1128 		err = -ENOBUFS;
1129 		goto out;
1130 	}
1131 
1132 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1133 	if (IS_ERR(f6i)) {
1134 		err = PTR_ERR(f6i);
1135 		f6i = NULL;
1136 		goto out;
1137 	}
1138 
1139 	neigh_parms_data_state_setall(idev->nd_parms);
1140 
1141 	ifa->addr = *cfg->pfx;
1142 	if (cfg->peer_pfx)
1143 		ifa->peer_addr = *cfg->peer_pfx;
1144 
1145 	spin_lock_init(&ifa->lock);
1146 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1147 	INIT_HLIST_NODE(&ifa->addr_lst);
1148 	ifa->scope = cfg->scope;
1149 	ifa->prefix_len = cfg->plen;
1150 	ifa->rt_priority = cfg->rt_priority;
1151 	ifa->flags = cfg->ifa_flags;
1152 	ifa->ifa_proto = cfg->ifa_proto;
1153 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1154 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1155 		ifa->flags |= IFA_F_TENTATIVE;
1156 	ifa->valid_lft = cfg->valid_lft;
1157 	ifa->prefered_lft = cfg->preferred_lft;
1158 	ifa->cstamp = ifa->tstamp = jiffies;
1159 	ifa->tokenized = false;
1160 
1161 	ifa->rt = f6i;
1162 
1163 	ifa->idev = idev;
1164 	in6_dev_hold(idev);
1165 
1166 	/* For caller */
1167 	refcount_set(&ifa->refcnt, 1);
1168 
1169 	rcu_read_lock();
1170 
1171 	err = ipv6_add_addr_hash(idev->dev, ifa);
1172 	if (err < 0) {
1173 		rcu_read_unlock();
1174 		goto out;
1175 	}
1176 
1177 	write_lock_bh(&idev->lock);
1178 
1179 	/* Add to inet6_dev unicast addr list. */
1180 	ipv6_link_dev_addr(idev, ifa);
1181 
1182 	if (ifa->flags&IFA_F_TEMPORARY) {
1183 		/* manage_tempaddrs() relies on addresses being added to the head */
1184 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1185 		in6_ifa_hold(ifa);
1186 	}
1187 
1188 	in6_ifa_hold(ifa);
1189 	write_unlock_bh(&idev->lock);
1190 
1191 	rcu_read_unlock();
1192 
1193 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1194 out:
1195 	if (unlikely(err < 0)) {
1196 		fib6_info_release(f6i);
1197 
1198 		if (ifa) {
1199 			if (ifa->idev)
1200 				in6_dev_put(ifa->idev);
1201 			kfree(ifa);
1202 		}
1203 		ifa = ERR_PTR(err);
1204 	}
1205 
1206 	return ifa;
1207 }
1208 
1209 enum cleanup_prefix_rt_t {
1210 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1211 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1212 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1213 };
1214 
1215 /*
1216  * Check, whether the prefix for ifp would still need a prefix route
1217  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1218  * constants.
1219  *
1220  * 1) we don't purge prefix if address was not permanent.
1221  *    prefix is managed by its own lifetime.
1222  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1223  * 3) if there are no addresses, delete prefix.
1224  * 4) if there are still other permanent address(es),
1225  *    corresponding prefix is still permanent.
1226  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1227  *    don't purge the prefix, assume user space is managing it.
1228  * 6) otherwise, update prefix lifetime to the
1229  *    longest valid lifetime among the corresponding
1230  *    addresses on the device.
1231  *    Note: subsequent RA will update lifetime.
1232  **/
1233 static enum cleanup_prefix_rt_t
1234 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1235 {
1236 	struct inet6_ifaddr *ifa;
1237 	struct inet6_dev *idev = ifp->idev;
1238 	unsigned long lifetime;
1239 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1240 
1241 	*expires = jiffies;
1242 
1243 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1244 		if (ifa == ifp)
1245 			continue;
1246 		if (ifa->prefix_len != ifp->prefix_len ||
1247 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1248 				       ifp->prefix_len))
1249 			continue;
1250 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1251 			return CLEANUP_PREFIX_RT_NOP;
1252 
1253 		action = CLEANUP_PREFIX_RT_EXPIRE;
1254 
1255 		spin_lock(&ifa->lock);
1256 
1257 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1258 		/*
1259 		 * Note: Because this address is
1260 		 * not permanent, lifetime <
1261 		 * LONG_MAX / HZ here.
1262 		 */
1263 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1264 			*expires = ifa->tstamp + lifetime * HZ;
1265 		spin_unlock(&ifa->lock);
1266 	}
1267 
1268 	return action;
1269 }
1270 
1271 static void
1272 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1273 		     bool del_rt, bool del_peer)
1274 {
1275 	struct net *net = dev_net(ifp->idev->dev);
1276 	struct fib6_table *table;
1277 	struct fib6_info *f6i;
1278 
1279 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1280 					ifp->prefix_len,
1281 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1282 	if (f6i) {
1283 		if (del_rt)
1284 			ip6_del_rt(net, f6i, false);
1285 		else {
1286 			if (f6i != net->ipv6.fib6_null_entry &&
1287 			    !(f6i->fib6_flags & RTF_EXPIRES)) {
1288 				table = f6i->fib6_table;
1289 				spin_lock_bh(&table->tb6_lock);
1290 
1291 				fib6_set_expires(f6i, expires);
1292 				fib6_add_gc_list(f6i);
1293 
1294 				spin_unlock_bh(&table->tb6_lock);
1295 			}
1296 			fib6_info_release(f6i);
1297 		}
1298 	}
1299 }
1300 
1301 
1302 /* This function wants to get referenced ifp and releases it before return */
1303 
1304 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1305 {
1306 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1307 	struct net *net = dev_net(ifp->idev->dev);
1308 	unsigned long expires;
1309 	int state;
1310 
1311 	ASSERT_RTNL();
1312 
1313 	spin_lock_bh(&ifp->lock);
1314 	state = ifp->state;
1315 	ifp->state = INET6_IFADDR_STATE_DEAD;
1316 	spin_unlock_bh(&ifp->lock);
1317 
1318 	if (state == INET6_IFADDR_STATE_DEAD)
1319 		goto out;
1320 
1321 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1322 	hlist_del_init_rcu(&ifp->addr_lst);
1323 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1324 
1325 	write_lock_bh(&ifp->idev->lock);
1326 
1327 	if (ifp->flags&IFA_F_TEMPORARY) {
1328 		list_del(&ifp->tmp_list);
1329 		if (ifp->ifpub) {
1330 			in6_ifa_put(ifp->ifpub);
1331 			ifp->ifpub = NULL;
1332 		}
1333 		__in6_ifa_put(ifp);
1334 	}
1335 
1336 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE))
1337 		action = check_cleanup_prefix_route(ifp, &expires);
1338 
1339 	list_del_rcu(&ifp->if_list);
1340 	__in6_ifa_put(ifp);
1341 
1342 	write_unlock_bh(&ifp->idev->lock);
1343 
1344 	addrconf_del_dad_work(ifp);
1345 
1346 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1347 
1348 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1349 
1350 	if (action != CLEANUP_PREFIX_RT_NOP) {
1351 		cleanup_prefix_route(ifp, expires,
1352 			action == CLEANUP_PREFIX_RT_DEL, false);
1353 	}
1354 
1355 	/* clean up prefsrc entries */
1356 	rt6_remove_prefsrc(ifp);
1357 out:
1358 	in6_ifa_put(ifp);
1359 }
1360 
1361 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1362 {
1363 	return READ_ONCE(idev->cnf.regen_min_advance) +
1364 		READ_ONCE(idev->cnf.regen_max_retry) *
1365 		READ_ONCE(idev->cnf.dad_transmits) *
1366 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1367 }
1368 
1369 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1370 {
1371 	struct inet6_dev *idev = ifp->idev;
1372 	unsigned long tmp_tstamp, age;
1373 	unsigned long regen_advance;
1374 	unsigned long now = jiffies;
1375 	u32 if_public_preferred_lft;
1376 	s32 cnf_temp_preferred_lft;
1377 	struct inet6_ifaddr *ift;
1378 	struct ifa6_config cfg;
1379 	long max_desync_factor;
1380 	struct in6_addr addr;
1381 	int ret = 0;
1382 
1383 	write_lock_bh(&idev->lock);
1384 
1385 retry:
1386 	in6_dev_hold(idev);
1387 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1388 		write_unlock_bh(&idev->lock);
1389 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1390 		in6_dev_put(idev);
1391 		ret = -1;
1392 		goto out;
1393 	}
1394 	spin_lock_bh(&ifp->lock);
1395 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1396 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1397 		spin_unlock_bh(&ifp->lock);
1398 		write_unlock_bh(&idev->lock);
1399 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1400 			__func__);
1401 		in6_dev_put(idev);
1402 		ret = -1;
1403 		goto out;
1404 	}
1405 	in6_ifa_hold(ifp);
1406 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1407 	ipv6_gen_rnd_iid(&addr);
1408 
1409 	age = (now - ifp->tstamp) / HZ;
1410 
1411 	regen_advance = ipv6_get_regen_advance(idev);
1412 
1413 	/* recalculate max_desync_factor each time and update
1414 	 * idev->desync_factor if it's larger
1415 	 */
1416 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1417 	max_desync_factor = min_t(long,
1418 				  READ_ONCE(idev->cnf.max_desync_factor),
1419 				  cnf_temp_preferred_lft - regen_advance);
1420 
1421 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1422 		if (max_desync_factor > 0) {
1423 			get_random_bytes(&idev->desync_factor,
1424 					 sizeof(idev->desync_factor));
1425 			idev->desync_factor %= max_desync_factor;
1426 		} else {
1427 			idev->desync_factor = 0;
1428 		}
1429 	}
1430 
1431 	if_public_preferred_lft = ifp->prefered_lft;
1432 
1433 	memset(&cfg, 0, sizeof(cfg));
1434 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1435 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1436 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1437 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1438 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1439 
1440 	cfg.plen = ifp->prefix_len;
1441 	tmp_tstamp = ifp->tstamp;
1442 	spin_unlock_bh(&ifp->lock);
1443 
1444 	write_unlock_bh(&idev->lock);
1445 
1446 	/* From RFC 4941:
1447 	 *
1448 	 *     A temporary address is created only if this calculated Preferred
1449 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1450 	 *     particular, an implementation must not create a temporary address
1451 	 *     with a zero Preferred Lifetime.
1452 	 *
1453 	 *     ...
1454 	 *
1455 	 *     When creating a temporary address, the lifetime values MUST be
1456 	 *     derived from the corresponding prefix as follows:
1457 	 *
1458 	 *     ...
1459 	 *
1460 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1461 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1462 	 *        DESYNC_FACTOR.
1463 	 *
1464 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1465 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1466 	 * ifp->prefered_lft.
1467 	 *
1468 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1469 	 * temporary addresses being generated.
1470 	 */
1471 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1472 	if (cfg.preferred_lft <= regen_advance + age) {
1473 		cfg.preferred_lft = regen_advance + age + 1;
1474 		if (cfg.preferred_lft > cfg.valid_lft ||
1475 		    cfg.preferred_lft > if_public_preferred_lft) {
1476 			in6_ifa_put(ifp);
1477 			in6_dev_put(idev);
1478 			ret = -1;
1479 			goto out;
1480 		}
1481 	}
1482 
1483 	cfg.ifa_flags = IFA_F_TEMPORARY;
1484 	/* set in addrconf_prefix_rcv() */
1485 	if (ifp->flags & IFA_F_OPTIMISTIC)
1486 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1487 
1488 	cfg.pfx = &addr;
1489 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1490 
1491 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1492 	if (IS_ERR(ift)) {
1493 		in6_ifa_put(ifp);
1494 		in6_dev_put(idev);
1495 		pr_info("%s: retry temporary address regeneration\n", __func__);
1496 		write_lock_bh(&idev->lock);
1497 		goto retry;
1498 	}
1499 
1500 	spin_lock_bh(&ift->lock);
1501 	ift->ifpub = ifp;
1502 	ift->cstamp = now;
1503 	ift->tstamp = tmp_tstamp;
1504 	spin_unlock_bh(&ift->lock);
1505 
1506 	addrconf_dad_start(ift);
1507 	in6_ifa_put(ift);
1508 	in6_dev_put(idev);
1509 out:
1510 	return ret;
1511 }
1512 
1513 /*
1514  *	Choose an appropriate source address (RFC3484)
1515  */
1516 enum {
1517 	IPV6_SADDR_RULE_INIT = 0,
1518 	IPV6_SADDR_RULE_LOCAL,
1519 	IPV6_SADDR_RULE_SCOPE,
1520 	IPV6_SADDR_RULE_PREFERRED,
1521 #ifdef CONFIG_IPV6_MIP6
1522 	IPV6_SADDR_RULE_HOA,
1523 #endif
1524 	IPV6_SADDR_RULE_OIF,
1525 	IPV6_SADDR_RULE_LABEL,
1526 	IPV6_SADDR_RULE_PRIVACY,
1527 	IPV6_SADDR_RULE_ORCHID,
1528 	IPV6_SADDR_RULE_PREFIX,
1529 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1530 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1531 #endif
1532 	IPV6_SADDR_RULE_MAX
1533 };
1534 
1535 struct ipv6_saddr_score {
1536 	int			rule;
1537 	int			addr_type;
1538 	struct inet6_ifaddr	*ifa;
1539 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1540 	int			scopedist;
1541 	int			matchlen;
1542 };
1543 
1544 struct ipv6_saddr_dst {
1545 	const struct in6_addr *addr;
1546 	int ifindex;
1547 	int scope;
1548 	int label;
1549 	unsigned int prefs;
1550 };
1551 
1552 static inline int ipv6_saddr_preferred(int type)
1553 {
1554 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1555 		return 1;
1556 	return 0;
1557 }
1558 
1559 static bool ipv6_use_optimistic_addr(const struct net *net,
1560 				     const struct inet6_dev *idev)
1561 {
1562 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1563 	if (!idev)
1564 		return false;
1565 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1566 	    !READ_ONCE(idev->cnf.optimistic_dad))
1567 		return false;
1568 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1569 	    !READ_ONCE(idev->cnf.use_optimistic))
1570 		return false;
1571 
1572 	return true;
1573 #else
1574 	return false;
1575 #endif
1576 }
1577 
1578 static bool ipv6_allow_optimistic_dad(const struct net *net,
1579 				      const struct inet6_dev *idev)
1580 {
1581 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1582 	if (!idev)
1583 		return false;
1584 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1585 	    !READ_ONCE(idev->cnf.optimistic_dad))
1586 		return false;
1587 
1588 	return true;
1589 #else
1590 	return false;
1591 #endif
1592 }
1593 
1594 static int ipv6_get_saddr_eval(struct net *net,
1595 			       struct ipv6_saddr_score *score,
1596 			       struct ipv6_saddr_dst *dst,
1597 			       int i)
1598 {
1599 	int ret;
1600 
1601 	if (i <= score->rule) {
1602 		switch (i) {
1603 		case IPV6_SADDR_RULE_SCOPE:
1604 			ret = score->scopedist;
1605 			break;
1606 		case IPV6_SADDR_RULE_PREFIX:
1607 			ret = score->matchlen;
1608 			break;
1609 		default:
1610 			ret = !!test_bit(i, score->scorebits);
1611 		}
1612 		goto out;
1613 	}
1614 
1615 	switch (i) {
1616 	case IPV6_SADDR_RULE_INIT:
1617 		/* Rule 0: remember if hiscore is not ready yet */
1618 		ret = !!score->ifa;
1619 		break;
1620 	case IPV6_SADDR_RULE_LOCAL:
1621 		/* Rule 1: Prefer same address */
1622 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1623 		break;
1624 	case IPV6_SADDR_RULE_SCOPE:
1625 		/* Rule 2: Prefer appropriate scope
1626 		 *
1627 		 *      ret
1628 		 *       ^
1629 		 *    -1 |  d 15
1630 		 *    ---+--+-+---> scope
1631 		 *       |
1632 		 *       |             d is scope of the destination.
1633 		 *  B-d  |  \
1634 		 *       |   \      <- smaller scope is better if
1635 		 *  B-15 |    \        if scope is enough for destination.
1636 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1637 		 * d-C-1 | /
1638 		 *       |/         <- greater is better
1639 		 *   -C  /             if scope is not enough for destination.
1640 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1641 		 *
1642 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1643 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1644 		 * Assume B = 0 and we get C > 29.
1645 		 */
1646 		ret = __ipv6_addr_src_scope(score->addr_type);
1647 		if (ret >= dst->scope)
1648 			ret = -ret;
1649 		else
1650 			ret -= 128;	/* 30 is enough */
1651 		score->scopedist = ret;
1652 		break;
1653 	case IPV6_SADDR_RULE_PREFERRED:
1654 	    {
1655 		/* Rule 3: Avoid deprecated and optimistic addresses */
1656 		u8 avoid = IFA_F_DEPRECATED;
1657 
1658 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1659 			avoid |= IFA_F_OPTIMISTIC;
1660 		ret = ipv6_saddr_preferred(score->addr_type) ||
1661 		      !(score->ifa->flags & avoid);
1662 		break;
1663 	    }
1664 #ifdef CONFIG_IPV6_MIP6
1665 	case IPV6_SADDR_RULE_HOA:
1666 	    {
1667 		/* Rule 4: Prefer home address */
1668 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1669 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1670 		break;
1671 	    }
1672 #endif
1673 	case IPV6_SADDR_RULE_OIF:
1674 		/* Rule 5: Prefer outgoing interface */
1675 		ret = (!dst->ifindex ||
1676 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1677 		break;
1678 	case IPV6_SADDR_RULE_LABEL:
1679 		/* Rule 6: Prefer matching label */
1680 		ret = ipv6_addr_label(net,
1681 				      &score->ifa->addr, score->addr_type,
1682 				      score->ifa->idev->dev->ifindex) == dst->label;
1683 		break;
1684 	case IPV6_SADDR_RULE_PRIVACY:
1685 	    {
1686 		/* Rule 7: Prefer public address
1687 		 * Note: prefer temporary address if use_tempaddr >= 2
1688 		 */
1689 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1690 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1691 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1692 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1693 		break;
1694 	    }
1695 	case IPV6_SADDR_RULE_ORCHID:
1696 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1697 		 *	    non-ORCHID vs non-ORCHID
1698 		 */
1699 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1700 			ipv6_addr_orchid(dst->addr));
1701 		break;
1702 	case IPV6_SADDR_RULE_PREFIX:
1703 		/* Rule 8: Use longest matching prefix */
1704 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1705 		if (ret > score->ifa->prefix_len)
1706 			ret = score->ifa->prefix_len;
1707 		score->matchlen = ret;
1708 		break;
1709 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1710 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1711 		/* Optimistic addresses still have lower precedence than other
1712 		 * preferred addresses.
1713 		 */
1714 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1715 		break;
1716 #endif
1717 	default:
1718 		ret = 0;
1719 	}
1720 
1721 	if (ret)
1722 		__set_bit(i, score->scorebits);
1723 	score->rule = i;
1724 out:
1725 	return ret;
1726 }
1727 
1728 static int __ipv6_dev_get_saddr(struct net *net,
1729 				struct ipv6_saddr_dst *dst,
1730 				struct inet6_dev *idev,
1731 				struct ipv6_saddr_score *scores,
1732 				int hiscore_idx)
1733 {
1734 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1735 
1736 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1737 		int i;
1738 
1739 		/*
1740 		 * - Tentative Address (RFC2462 section 5.4)
1741 		 *  - A tentative address is not considered
1742 		 *    "assigned to an interface" in the traditional
1743 		 *    sense, unless it is also flagged as optimistic.
1744 		 * - Candidate Source Address (section 4)
1745 		 *  - In any case, anycast addresses, multicast
1746 		 *    addresses, and the unspecified address MUST
1747 		 *    NOT be included in a candidate set.
1748 		 */
1749 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1750 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1751 			continue;
1752 
1753 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1754 
1755 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1756 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1757 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1758 					    idev->dev->name);
1759 			continue;
1760 		}
1761 
1762 		score->rule = -1;
1763 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1764 
1765 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1766 			int minihiscore, miniscore;
1767 
1768 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1769 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1770 
1771 			if (minihiscore > miniscore) {
1772 				if (i == IPV6_SADDR_RULE_SCOPE &&
1773 				    score->scopedist > 0) {
1774 					/*
1775 					 * special case:
1776 					 * each remaining entry
1777 					 * has too small (not enough)
1778 					 * scope, because ifa entries
1779 					 * are sorted by their scope
1780 					 * values.
1781 					 */
1782 					goto out;
1783 				}
1784 				break;
1785 			} else if (minihiscore < miniscore) {
1786 				swap(hiscore, score);
1787 				hiscore_idx = 1 - hiscore_idx;
1788 
1789 				/* restore our iterator */
1790 				score->ifa = hiscore->ifa;
1791 
1792 				break;
1793 			}
1794 		}
1795 	}
1796 out:
1797 	return hiscore_idx;
1798 }
1799 
1800 static int ipv6_get_saddr_master(struct net *net,
1801 				 const struct net_device *dst_dev,
1802 				 const struct net_device *master,
1803 				 struct ipv6_saddr_dst *dst,
1804 				 struct ipv6_saddr_score *scores,
1805 				 int hiscore_idx)
1806 {
1807 	struct inet6_dev *idev;
1808 
1809 	idev = __in6_dev_get(dst_dev);
1810 	if (idev)
1811 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1812 						   scores, hiscore_idx);
1813 
1814 	idev = __in6_dev_get(master);
1815 	if (idev)
1816 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1817 						   scores, hiscore_idx);
1818 
1819 	return hiscore_idx;
1820 }
1821 
1822 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1823 		       const struct in6_addr *daddr, unsigned int prefs,
1824 		       struct in6_addr *saddr)
1825 {
1826 	struct ipv6_saddr_score scores[2], *hiscore;
1827 	struct ipv6_saddr_dst dst;
1828 	struct inet6_dev *idev;
1829 	struct net_device *dev;
1830 	int dst_type;
1831 	bool use_oif_addr = false;
1832 	int hiscore_idx = 0;
1833 	int ret = 0;
1834 
1835 	dst_type = __ipv6_addr_type(daddr);
1836 	dst.addr = daddr;
1837 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1838 	dst.scope = __ipv6_addr_src_scope(dst_type);
1839 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1840 	dst.prefs = prefs;
1841 
1842 	scores[hiscore_idx].rule = -1;
1843 	scores[hiscore_idx].ifa = NULL;
1844 
1845 	rcu_read_lock();
1846 
1847 	/* Candidate Source Address (section 4)
1848 	 *  - multicast and link-local destination address,
1849 	 *    the set of candidate source address MUST only
1850 	 *    include addresses assigned to interfaces
1851 	 *    belonging to the same link as the outgoing
1852 	 *    interface.
1853 	 * (- For site-local destination addresses, the
1854 	 *    set of candidate source addresses MUST only
1855 	 *    include addresses assigned to interfaces
1856 	 *    belonging to the same site as the outgoing
1857 	 *    interface.)
1858 	 *  - "It is RECOMMENDED that the candidate source addresses
1859 	 *    be the set of unicast addresses assigned to the
1860 	 *    interface that will be used to send to the destination
1861 	 *    (the 'outgoing' interface)." (RFC 6724)
1862 	 */
1863 	if (dst_dev) {
1864 		idev = __in6_dev_get(dst_dev);
1865 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1866 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1867 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1868 			use_oif_addr = true;
1869 		}
1870 	}
1871 
1872 	if (use_oif_addr) {
1873 		if (idev)
1874 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1875 	} else {
1876 		const struct net_device *master;
1877 		int master_idx = 0;
1878 
1879 		/* if dst_dev exists and is enslaved to an L3 device, then
1880 		 * prefer addresses from dst_dev and then the master over
1881 		 * any other enslaved devices in the L3 domain.
1882 		 */
1883 		master = l3mdev_master_dev_rcu(dst_dev);
1884 		if (master) {
1885 			master_idx = master->ifindex;
1886 
1887 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1888 							    master, &dst,
1889 							    scores, hiscore_idx);
1890 
1891 			if (scores[hiscore_idx].ifa &&
1892 			    scores[hiscore_idx].scopedist >= 0)
1893 				goto out;
1894 		}
1895 
1896 		for_each_netdev_rcu(net, dev) {
1897 			/* only consider addresses on devices in the
1898 			 * same L3 domain
1899 			 */
1900 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1901 				continue;
1902 			idev = __in6_dev_get(dev);
1903 			if (!idev)
1904 				continue;
1905 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1906 		}
1907 	}
1908 
1909 out:
1910 	hiscore = &scores[hiscore_idx];
1911 	if (!hiscore->ifa)
1912 		ret = -EADDRNOTAVAIL;
1913 	else
1914 		*saddr = hiscore->ifa->addr;
1915 
1916 	rcu_read_unlock();
1917 	return ret;
1918 }
1919 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1920 
1921 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1922 			      u32 banned_flags)
1923 {
1924 	struct inet6_ifaddr *ifp;
1925 	int err = -EADDRNOTAVAIL;
1926 
1927 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1928 		if (ifp->scope > IFA_LINK)
1929 			break;
1930 		if (ifp->scope == IFA_LINK &&
1931 		    !(ifp->flags & banned_flags)) {
1932 			*addr = ifp->addr;
1933 			err = 0;
1934 			break;
1935 		}
1936 	}
1937 	return err;
1938 }
1939 
1940 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1941 		    u32 banned_flags)
1942 {
1943 	struct inet6_dev *idev;
1944 	int err = -EADDRNOTAVAIL;
1945 
1946 	rcu_read_lock();
1947 	idev = __in6_dev_get(dev);
1948 	if (idev) {
1949 		read_lock_bh(&idev->lock);
1950 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1951 		read_unlock_bh(&idev->lock);
1952 	}
1953 	rcu_read_unlock();
1954 	return err;
1955 }
1956 
1957 static int ipv6_count_addresses(const struct inet6_dev *idev)
1958 {
1959 	const struct inet6_ifaddr *ifp;
1960 	int cnt = 0;
1961 
1962 	rcu_read_lock();
1963 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1964 		cnt++;
1965 	rcu_read_unlock();
1966 	return cnt;
1967 }
1968 
1969 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1970 		  const struct net_device *dev, int strict)
1971 {
1972 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1973 				       strict, IFA_F_TENTATIVE);
1974 }
1975 EXPORT_SYMBOL(ipv6_chk_addr);
1976 
1977 /* device argument is used to find the L3 domain of interest. If
1978  * skip_dev_check is set, then the ifp device is not checked against
1979  * the passed in dev argument. So the 2 cases for addresses checks are:
1980  *   1. does the address exist in the L3 domain that dev is part of
1981  *      (skip_dev_check = true), or
1982  *
1983  *   2. does the address exist on the specific device
1984  *      (skip_dev_check = false)
1985  */
1986 static struct net_device *
1987 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1988 			  const struct net_device *dev, bool skip_dev_check,
1989 			  int strict, u32 banned_flags)
1990 {
1991 	unsigned int hash = inet6_addr_hash(net, addr);
1992 	struct net_device *l3mdev, *ndev;
1993 	struct inet6_ifaddr *ifp;
1994 	u32 ifp_flags;
1995 
1996 	rcu_read_lock();
1997 
1998 	l3mdev = l3mdev_master_dev_rcu(dev);
1999 	if (skip_dev_check)
2000 		dev = NULL;
2001 
2002 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2003 		ndev = ifp->idev->dev;
2004 
2005 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
2006 			continue;
2007 
2008 		/* Decouple optimistic from tentative for evaluation here.
2009 		 * Ban optimistic addresses explicitly, when required.
2010 		 */
2011 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
2012 			    ? (ifp->flags&~IFA_F_TENTATIVE)
2013 			    : ifp->flags;
2014 		if (ipv6_addr_equal(&ifp->addr, addr) &&
2015 		    !(ifp_flags&banned_flags) &&
2016 		    (!dev || ndev == dev ||
2017 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2018 			rcu_read_unlock();
2019 			return ndev;
2020 		}
2021 	}
2022 
2023 	rcu_read_unlock();
2024 	return NULL;
2025 }
2026 
2027 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2028 			    const struct net_device *dev, bool skip_dev_check,
2029 			    int strict, u32 banned_flags)
2030 {
2031 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2032 					 strict, banned_flags) ? 1 : 0;
2033 }
2034 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2035 
2036 
2037 /* Compares an address/prefix_len with addresses on device @dev.
2038  * If one is found it returns true.
2039  */
2040 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2041 	const unsigned int prefix_len, struct net_device *dev)
2042 {
2043 	const struct inet6_ifaddr *ifa;
2044 	const struct inet6_dev *idev;
2045 	bool ret = false;
2046 
2047 	rcu_read_lock();
2048 	idev = __in6_dev_get(dev);
2049 	if (idev) {
2050 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2051 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2052 			if (ret)
2053 				break;
2054 		}
2055 	}
2056 	rcu_read_unlock();
2057 
2058 	return ret;
2059 }
2060 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2061 
2062 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2063 {
2064 	const struct inet6_ifaddr *ifa;
2065 	const struct inet6_dev *idev;
2066 	int	onlink;
2067 
2068 	onlink = 0;
2069 	rcu_read_lock();
2070 	idev = __in6_dev_get(dev);
2071 	if (idev) {
2072 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2073 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2074 						   ifa->prefix_len);
2075 			if (onlink)
2076 				break;
2077 		}
2078 	}
2079 	rcu_read_unlock();
2080 	return onlink;
2081 }
2082 EXPORT_SYMBOL(ipv6_chk_prefix);
2083 
2084 /**
2085  * ipv6_dev_find - find the first device with a given source address.
2086  * @net: the net namespace
2087  * @addr: the source address
2088  * @dev: used to find the L3 domain of interest
2089  *
2090  * The caller should be protected by RCU, or RTNL.
2091  */
2092 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2093 				 struct net_device *dev)
2094 {
2095 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2096 					 IFA_F_TENTATIVE);
2097 }
2098 EXPORT_SYMBOL(ipv6_dev_find);
2099 
2100 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2101 				     struct net_device *dev, int strict)
2102 {
2103 	unsigned int hash = inet6_addr_hash(net, addr);
2104 	struct inet6_ifaddr *ifp, *result = NULL;
2105 
2106 	rcu_read_lock();
2107 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2108 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2109 			if (!dev || ifp->idev->dev == dev ||
2110 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2111 				if (in6_ifa_hold_safe(ifp)) {
2112 					result = ifp;
2113 					break;
2114 				}
2115 			}
2116 		}
2117 	}
2118 	rcu_read_unlock();
2119 
2120 	return result;
2121 }
2122 
2123 /* Gets referenced address, destroys ifaddr */
2124 
2125 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2126 {
2127 	if (dad_failed)
2128 		ifp->flags |= IFA_F_DADFAILED;
2129 
2130 	if (ifp->flags&IFA_F_TEMPORARY) {
2131 		struct inet6_ifaddr *ifpub;
2132 		spin_lock_bh(&ifp->lock);
2133 		ifpub = ifp->ifpub;
2134 		if (ifpub) {
2135 			in6_ifa_hold(ifpub);
2136 			spin_unlock_bh(&ifp->lock);
2137 			ipv6_create_tempaddr(ifpub, true);
2138 			in6_ifa_put(ifpub);
2139 		} else {
2140 			spin_unlock_bh(&ifp->lock);
2141 		}
2142 		ipv6_del_addr(ifp);
2143 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2144 		spin_lock_bh(&ifp->lock);
2145 		addrconf_del_dad_work(ifp);
2146 		ifp->flags |= IFA_F_TENTATIVE;
2147 		if (dad_failed)
2148 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2149 		spin_unlock_bh(&ifp->lock);
2150 		if (dad_failed)
2151 			ipv6_ifa_notify(0, ifp);
2152 		in6_ifa_put(ifp);
2153 	} else {
2154 		ipv6_del_addr(ifp);
2155 	}
2156 }
2157 
2158 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2159 {
2160 	int err = -ENOENT;
2161 
2162 	spin_lock_bh(&ifp->lock);
2163 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2164 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2165 		err = 0;
2166 	}
2167 	spin_unlock_bh(&ifp->lock);
2168 
2169 	return err;
2170 }
2171 
2172 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2173 {
2174 	struct inet6_dev *idev = ifp->idev;
2175 	struct net *net = dev_net(idev->dev);
2176 	int max_addresses;
2177 
2178 	spin_lock_bh(&ifp->lock);
2179 
2180 	if (ifp->state != INET6_IFADDR_STATE_DAD) {
2181 		spin_unlock_bh(&ifp->lock);
2182 		in6_ifa_put(ifp);
2183 		return;
2184 	}
2185 	ifp->state = INET6_IFADDR_STATE_POSTDAD;
2186 
2187 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2188 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2189 
2190 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2191 		struct in6_addr new_addr;
2192 		struct inet6_ifaddr *ifp2;
2193 		int retries = ifp->stable_privacy_retry + 1;
2194 		struct ifa6_config cfg = {
2195 			.pfx = &new_addr,
2196 			.plen = ifp->prefix_len,
2197 			.ifa_flags = ifp->flags,
2198 			.valid_lft = ifp->valid_lft,
2199 			.preferred_lft = ifp->prefered_lft,
2200 			.scope = ifp->scope,
2201 		};
2202 
2203 		if (retries > net->ipv6.sysctl.idgen_retries) {
2204 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2205 					     ifp->idev->dev->name);
2206 			goto errdad;
2207 		}
2208 
2209 		new_addr = ifp->addr;
2210 		if (ipv6_generate_stable_address(&new_addr, retries,
2211 						 idev))
2212 			goto errdad;
2213 
2214 		spin_unlock_bh(&ifp->lock);
2215 
2216 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2217 		if (max_addresses &&
2218 		    ipv6_count_addresses(idev) >= max_addresses)
2219 			goto lock_errdad;
2220 
2221 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2222 				     ifp->idev->dev->name);
2223 
2224 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2225 		if (IS_ERR(ifp2))
2226 			goto lock_errdad;
2227 
2228 		spin_lock_bh(&ifp2->lock);
2229 		ifp2->stable_privacy_retry = retries;
2230 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2231 		spin_unlock_bh(&ifp2->lock);
2232 
2233 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2234 		in6_ifa_put(ifp2);
2235 lock_errdad:
2236 		spin_lock_bh(&ifp->lock);
2237 		if (ifp->state != INET6_IFADDR_STATE_POSTDAD) {
2238 			spin_unlock_bh(&ifp->lock);
2239 			in6_ifa_put(ifp);
2240 			return;
2241 		}
2242 	}
2243 
2244 errdad:
2245 	/* transition from _POSTDAD to _ERRDAD */
2246 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2247 	spin_unlock_bh(&ifp->lock);
2248 
2249 	addrconf_mod_dad_work(ifp, 0);
2250 	in6_ifa_put(ifp);
2251 }
2252 
2253 /* Join to solicited addr multicast group. */
2254 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2255 {
2256 	struct in6_addr maddr;
2257 
2258 	if (READ_ONCE(dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2259 		return;
2260 
2261 	addrconf_addr_solict_mult(addr, &maddr);
2262 	ipv6_dev_mc_inc(dev, &maddr);
2263 }
2264 
2265 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2266 {
2267 	struct in6_addr maddr;
2268 
2269 	if (READ_ONCE(idev->dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2270 		return;
2271 
2272 	addrconf_addr_solict_mult(addr, &maddr);
2273 	__ipv6_dev_mc_dec(idev, &maddr);
2274 }
2275 
2276 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2277 {
2278 	struct in6_addr addr;
2279 
2280 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2281 		return;
2282 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2283 	if (ipv6_addr_any(&addr))
2284 		return;
2285 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2286 }
2287 
2288 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2289 {
2290 	struct in6_addr addr;
2291 
2292 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2293 		return;
2294 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2295 	if (ipv6_addr_any(&addr))
2296 		return;
2297 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2298 }
2299 
2300 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2301 {
2302 	switch (dev->addr_len) {
2303 	case ETH_ALEN:
2304 		memcpy(eui, dev->dev_addr, 3);
2305 		eui[3] = 0xFF;
2306 		eui[4] = 0xFE;
2307 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2308 		break;
2309 	case EUI64_ADDR_LEN:
2310 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2311 		eui[0] ^= 2;
2312 		break;
2313 	default:
2314 		return -1;
2315 	}
2316 
2317 	return 0;
2318 }
2319 
2320 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2321 {
2322 	const union fwnet_hwaddr *ha;
2323 
2324 	if (dev->addr_len != FWNET_ALEN)
2325 		return -1;
2326 
2327 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2328 
2329 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2330 	eui[0] ^= 2;
2331 	return 0;
2332 }
2333 
2334 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2335 {
2336 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2337 	if (dev->addr_len != ARCNET_ALEN)
2338 		return -1;
2339 	memset(eui, 0, 7);
2340 	eui[7] = *(u8 *)dev->dev_addr;
2341 	return 0;
2342 }
2343 
2344 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2345 {
2346 	if (dev->addr_len != INFINIBAND_ALEN)
2347 		return -1;
2348 	memcpy(eui, dev->dev_addr + 12, 8);
2349 	eui[0] |= 2;
2350 	return 0;
2351 }
2352 
2353 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2354 {
2355 	if (addr == 0)
2356 		return -1;
2357 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2358 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2359 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2360 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2361 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2362 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2363 	eui[1] = 0;
2364 	eui[2] = 0x5E;
2365 	eui[3] = 0xFE;
2366 	memcpy(eui + 4, &addr, 4);
2367 	return 0;
2368 }
2369 
2370 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2371 {
2372 	if (dev->priv_flags & IFF_ISATAP)
2373 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2374 	return -1;
2375 }
2376 
2377 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2378 {
2379 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2380 }
2381 
2382 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2383 {
2384 	memcpy(eui, dev->perm_addr, 3);
2385 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2386 	eui[3] = 0xFF;
2387 	eui[4] = 0xFE;
2388 	eui[0] ^= 2;
2389 	return 0;
2390 }
2391 
2392 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2393 {
2394 	switch (dev->type) {
2395 	case ARPHRD_ETHER:
2396 	case ARPHRD_FDDI:
2397 		return addrconf_ifid_eui48(eui, dev);
2398 	case ARPHRD_ARCNET:
2399 		return addrconf_ifid_arcnet(eui, dev);
2400 	case ARPHRD_INFINIBAND:
2401 		return addrconf_ifid_infiniband(eui, dev);
2402 	case ARPHRD_SIT:
2403 		return addrconf_ifid_sit(eui, dev);
2404 	case ARPHRD_IPGRE:
2405 	case ARPHRD_TUNNEL:
2406 		return addrconf_ifid_gre(eui, dev);
2407 	case ARPHRD_6LOWPAN:
2408 		return addrconf_ifid_6lowpan(eui, dev);
2409 	case ARPHRD_IEEE1394:
2410 		return addrconf_ifid_ieee1394(eui, dev);
2411 	case ARPHRD_TUNNEL6:
2412 	case ARPHRD_IP6GRE:
2413 	case ARPHRD_RAWIP:
2414 		return addrconf_ifid_ip6tnl(eui, dev);
2415 	}
2416 	return -1;
2417 }
2418 
2419 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2420 {
2421 	int err = -1;
2422 	struct inet6_ifaddr *ifp;
2423 
2424 	read_lock_bh(&idev->lock);
2425 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2426 		if (ifp->scope > IFA_LINK)
2427 			break;
2428 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2429 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2430 			err = 0;
2431 			break;
2432 		}
2433 	}
2434 	read_unlock_bh(&idev->lock);
2435 	return err;
2436 }
2437 
2438 /* Generation of a randomized Interface Identifier
2439  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2440  */
2441 
2442 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2443 {
2444 regen:
2445 	get_random_bytes(&addr->s6_addr[8], 8);
2446 
2447 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2448 	 * check if generated address is not inappropriate:
2449 	 *
2450 	 * - Reserved IPv6 Interface Identifiers
2451 	 * - XXX: already assigned to an address on the device
2452 	 */
2453 
2454 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2455 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2456 		goto regen;
2457 
2458 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2459 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2460 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2461 	 */
2462 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2463 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2464 		goto regen;
2465 
2466 	/* Reserved subnet anycast addresses */
2467 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2468 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2469 		goto regen;
2470 }
2471 
2472 /*
2473  *	Add prefix route.
2474  */
2475 
2476 static void
2477 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2478 		      struct net_device *dev, unsigned long expires,
2479 		      u32 flags, gfp_t gfp_flags)
2480 {
2481 	struct fib6_config cfg = {
2482 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2483 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2484 		.fc_ifindex = dev->ifindex,
2485 		.fc_expires = expires,
2486 		.fc_dst_len = plen,
2487 		.fc_flags = RTF_UP | flags,
2488 		.fc_nlinfo.nl_net = dev_net(dev),
2489 		.fc_protocol = RTPROT_KERNEL,
2490 		.fc_type = RTN_UNICAST,
2491 	};
2492 
2493 	cfg.fc_dst = *pfx;
2494 
2495 	/* Prevent useless cloning on PtP SIT.
2496 	   This thing is done here expecting that the whole
2497 	   class of non-broadcast devices need not cloning.
2498 	 */
2499 #if IS_ENABLED(CONFIG_IPV6_SIT)
2500 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2501 		cfg.fc_flags |= RTF_NONEXTHOP;
2502 #endif
2503 
2504 	ip6_route_add(&cfg, gfp_flags, NULL);
2505 }
2506 
2507 
2508 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2509 						  int plen,
2510 						  const struct net_device *dev,
2511 						  u32 flags, u32 noflags,
2512 						  bool no_gw)
2513 {
2514 	struct fib6_node *fn;
2515 	struct fib6_info *rt = NULL;
2516 	struct fib6_table *table;
2517 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2518 
2519 	table = fib6_get_table(dev_net(dev), tb_id);
2520 	if (!table)
2521 		return NULL;
2522 
2523 	rcu_read_lock();
2524 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2525 	if (!fn)
2526 		goto out;
2527 
2528 	for_each_fib6_node_rt_rcu(fn) {
2529 		/* prefix routes only use builtin fib6_nh */
2530 		if (rt->nh)
2531 			continue;
2532 
2533 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2534 			continue;
2535 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2536 			continue;
2537 		if ((rt->fib6_flags & flags) != flags)
2538 			continue;
2539 		if ((rt->fib6_flags & noflags) != 0)
2540 			continue;
2541 		if (!fib6_info_hold_safe(rt))
2542 			continue;
2543 		break;
2544 	}
2545 out:
2546 	rcu_read_unlock();
2547 	return rt;
2548 }
2549 
2550 
2551 /* Create "default" multicast route to the interface */
2552 
2553 static void addrconf_add_mroute(struct net_device *dev)
2554 {
2555 	struct fib6_config cfg = {
2556 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2557 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2558 		.fc_ifindex = dev->ifindex,
2559 		.fc_dst_len = 8,
2560 		.fc_flags = RTF_UP,
2561 		.fc_type = RTN_MULTICAST,
2562 		.fc_nlinfo.nl_net = dev_net(dev),
2563 		.fc_protocol = RTPROT_KERNEL,
2564 	};
2565 
2566 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2567 
2568 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2569 }
2570 
2571 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2572 {
2573 	struct inet6_dev *idev;
2574 
2575 	ASSERT_RTNL();
2576 
2577 	idev = ipv6_find_idev(dev);
2578 	if (IS_ERR(idev))
2579 		return idev;
2580 
2581 	if (idev->cnf.disable_ipv6)
2582 		return ERR_PTR(-EACCES);
2583 
2584 	/* Add default multicast route */
2585 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2586 		addrconf_add_mroute(dev);
2587 
2588 	return idev;
2589 }
2590 
2591 static void delete_tempaddrs(struct inet6_dev *idev,
2592 			     struct inet6_ifaddr *ifp)
2593 {
2594 	struct inet6_ifaddr *ift, *tmp;
2595 
2596 	write_lock_bh(&idev->lock);
2597 	list_for_each_entry_safe(ift, tmp, &idev->tempaddr_list, tmp_list) {
2598 		if (ift->ifpub != ifp)
2599 			continue;
2600 
2601 		in6_ifa_hold(ift);
2602 		write_unlock_bh(&idev->lock);
2603 		ipv6_del_addr(ift);
2604 		write_lock_bh(&idev->lock);
2605 	}
2606 	write_unlock_bh(&idev->lock);
2607 }
2608 
2609 static void manage_tempaddrs(struct inet6_dev *idev,
2610 			     struct inet6_ifaddr *ifp,
2611 			     __u32 valid_lft, __u32 prefered_lft,
2612 			     bool create, unsigned long now)
2613 {
2614 	u32 orig_prefered_lft = prefered_lft;
2615 	struct inet6_ifaddr *ift;
2616 	bool reset_done = false;
2617 	u32 flags;
2618 
2619 	read_lock_bh(&idev->lock);
2620 	/* update all temporary addresses in the list */
2621 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2622 		int age, max_valid, max_prefered;
2623 
2624 		if (ifp != ift->ifpub)
2625 			continue;
2626 
2627 		/* RFC 4941 section 3.3:
2628 		 * If a received option will extend the lifetime of a public
2629 		 * address, the lifetimes of temporary addresses should
2630 		 * be extended, subject to the overall constraint that no
2631 		 * temporary addresses should ever remain "valid" or "preferred"
2632 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2633 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2634 		 */
2635 		age = (now - ift->cstamp) / HZ;
2636 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2637 		if (max_valid < 0)
2638 			max_valid = 0;
2639 
2640 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2641 			       idev->desync_factor - age;
2642 		if (max_prefered < 0)
2643 			max_prefered = 0;
2644 
2645 		if (valid_lft > max_valid)
2646 			valid_lft = max_valid;
2647 
2648 		if (prefered_lft > max_prefered)
2649 			prefered_lft = max_prefered;
2650 
2651 		spin_lock(&ift->lock);
2652 		/* the first match is the most recent temp address */
2653 		if (!reset_done && orig_prefered_lft > 0) {
2654 			ift->regen_count = 0;
2655 			reset_done = true;
2656 		}
2657 		flags = ift->flags;
2658 		ift->valid_lft = valid_lft;
2659 		ift->prefered_lft = prefered_lft;
2660 		ift->tstamp = now;
2661 		if (prefered_lft > 0)
2662 			ift->flags &= ~IFA_F_DEPRECATED;
2663 
2664 		spin_unlock(&ift->lock);
2665 		if (!(flags&IFA_F_TENTATIVE))
2666 			ipv6_ifa_notify(0, ift);
2667 	}
2668 
2669 	/* Also create a temporary address if it's enabled but no temporary
2670 	 * address currently exists.
2671 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2672 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2673 	 * We don't want that to result in creating a new temporary ip address.
2674 	 */
2675 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2676 		create = true;
2677 
2678 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2679 		/* When a new public address is created as described
2680 		 * in [ADDRCONF], also create a new temporary address.
2681 		 */
2682 		read_unlock_bh(&idev->lock);
2683 		ipv6_create_tempaddr(ifp, false);
2684 	} else {
2685 		read_unlock_bh(&idev->lock);
2686 	}
2687 }
2688 
2689 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2690 {
2691 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2692 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2693 }
2694 
2695 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2696 				 const struct prefix_info *pinfo,
2697 				 struct inet6_dev *in6_dev,
2698 				 const struct in6_addr *addr, int addr_type,
2699 				 u32 addr_flags, bool sllao, bool tokenized,
2700 				 __u32 valid_lft, u32 prefered_lft)
2701 {
2702 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2703 	int create = 0, update_lft = 0;
2704 
2705 	if (!ifp && valid_lft) {
2706 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2707 		struct ifa6_config cfg = {
2708 			.pfx = addr,
2709 			.plen = pinfo->prefix_len,
2710 			.ifa_flags = addr_flags,
2711 			.valid_lft = valid_lft,
2712 			.preferred_lft = prefered_lft,
2713 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2714 			.ifa_proto = IFAPROT_KERNEL_RA
2715 		};
2716 
2717 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2718 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2719 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2720 		    !net->ipv6.devconf_all->forwarding && sllao)
2721 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2722 #endif
2723 
2724 		/* Do not allow to create too much of autoconfigured
2725 		 * addresses; this would be too easy way to crash kernel.
2726 		 */
2727 		if (!max_addresses ||
2728 		    ipv6_count_addresses(in6_dev) < max_addresses)
2729 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2730 
2731 		if (IS_ERR_OR_NULL(ifp))
2732 			return -1;
2733 
2734 		create = 1;
2735 		spin_lock_bh(&ifp->lock);
2736 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2737 		ifp->cstamp = jiffies;
2738 		ifp->tokenized = tokenized;
2739 		spin_unlock_bh(&ifp->lock);
2740 		addrconf_dad_start(ifp);
2741 	}
2742 
2743 	if (ifp) {
2744 		u32 flags;
2745 		unsigned long now;
2746 		u32 stored_lft;
2747 
2748 		/* update lifetime (RFC2462 5.5.3 e) */
2749 		spin_lock_bh(&ifp->lock);
2750 		now = jiffies;
2751 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2752 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2753 		else
2754 			stored_lft = 0;
2755 
2756 		/* RFC4862 Section 5.5.3e:
2757 		 * "Note that the preferred lifetime of the
2758 		 *  corresponding address is always reset to
2759 		 *  the Preferred Lifetime in the received
2760 		 *  Prefix Information option, regardless of
2761 		 *  whether the valid lifetime is also reset or
2762 		 *  ignored."
2763 		 *
2764 		 * So we should always update prefered_lft here.
2765 		 */
2766 		update_lft = !create && stored_lft;
2767 
2768 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2769 			const u32 minimum_lft = min_t(u32,
2770 				stored_lft, MIN_VALID_LIFETIME);
2771 			valid_lft = max(valid_lft, minimum_lft);
2772 		}
2773 
2774 		if (update_lft) {
2775 			ifp->valid_lft = valid_lft;
2776 			ifp->prefered_lft = prefered_lft;
2777 			WRITE_ONCE(ifp->tstamp, now);
2778 			flags = ifp->flags;
2779 			ifp->flags &= ~IFA_F_DEPRECATED;
2780 			spin_unlock_bh(&ifp->lock);
2781 
2782 			if (!(flags&IFA_F_TENTATIVE))
2783 				ipv6_ifa_notify(0, ifp);
2784 		} else
2785 			spin_unlock_bh(&ifp->lock);
2786 
2787 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2788 				 create, now);
2789 
2790 		in6_ifa_put(ifp);
2791 		addrconf_verify(net);
2792 	}
2793 
2794 	return 0;
2795 }
2796 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2797 
2798 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2799 {
2800 	struct prefix_info *pinfo;
2801 	struct fib6_table *table;
2802 	__u32 valid_lft;
2803 	__u32 prefered_lft;
2804 	int addr_type, err;
2805 	u32 addr_flags = 0;
2806 	struct inet6_dev *in6_dev;
2807 	struct net *net = dev_net(dev);
2808 	bool ignore_autoconf = false;
2809 
2810 	pinfo = (struct prefix_info *) opt;
2811 
2812 	if (len < sizeof(struct prefix_info)) {
2813 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2814 		return;
2815 	}
2816 
2817 	/*
2818 	 *	Validation checks ([ADDRCONF], page 19)
2819 	 */
2820 
2821 	addr_type = ipv6_addr_type(&pinfo->prefix);
2822 
2823 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2824 		return;
2825 
2826 	valid_lft = ntohl(pinfo->valid);
2827 	prefered_lft = ntohl(pinfo->prefered);
2828 
2829 	if (prefered_lft > valid_lft) {
2830 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2831 		return;
2832 	}
2833 
2834 	in6_dev = in6_dev_get(dev);
2835 
2836 	if (!in6_dev) {
2837 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2838 				    dev->name);
2839 		return;
2840 	}
2841 
2842 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2843 		goto put;
2844 
2845 	/*
2846 	 *	Two things going on here:
2847 	 *	1) Add routes for on-link prefixes
2848 	 *	2) Configure prefixes with the auto flag set
2849 	 */
2850 
2851 	if (pinfo->onlink) {
2852 		struct fib6_info *rt;
2853 		unsigned long rt_expires;
2854 
2855 		/* Avoid arithmetic overflow. Really, we could
2856 		 * save rt_expires in seconds, likely valid_lft,
2857 		 * but it would require division in fib gc, that it
2858 		 * not good.
2859 		 */
2860 		if (HZ > USER_HZ)
2861 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2862 		else
2863 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2864 
2865 		if (addrconf_finite_timeout(rt_expires))
2866 			rt_expires *= HZ;
2867 
2868 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2869 					       pinfo->prefix_len,
2870 					       dev,
2871 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2872 					       RTF_DEFAULT, true);
2873 
2874 		if (rt) {
2875 			/* Autoconf prefix route */
2876 			if (valid_lft == 0) {
2877 				ip6_del_rt(net, rt, false);
2878 				rt = NULL;
2879 			} else {
2880 				table = rt->fib6_table;
2881 				spin_lock_bh(&table->tb6_lock);
2882 
2883 				if (addrconf_finite_timeout(rt_expires)) {
2884 					/* not infinity */
2885 					fib6_set_expires(rt, jiffies + rt_expires);
2886 					fib6_add_gc_list(rt);
2887 				} else {
2888 					fib6_clean_expires(rt);
2889 					fib6_may_remove_gc_list(net, rt);
2890 				}
2891 
2892 				spin_unlock_bh(&table->tb6_lock);
2893 			}
2894 		} else if (valid_lft) {
2895 			clock_t expires = 0;
2896 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2897 			if (addrconf_finite_timeout(rt_expires)) {
2898 				/* not infinity */
2899 				flags |= RTF_EXPIRES;
2900 				expires = jiffies_to_clock_t(rt_expires);
2901 			}
2902 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2903 					      0, dev, expires, flags,
2904 					      GFP_ATOMIC);
2905 		}
2906 		fib6_info_release(rt);
2907 	}
2908 
2909 	/* Try to figure out our local address for this prefix */
2910 
2911 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2912 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2913 		struct in6_addr addr;
2914 		bool tokenized = false, dev_addr_generated = false;
2915 
2916 		if (pinfo->prefix_len == 64) {
2917 			memcpy(&addr, &pinfo->prefix, 8);
2918 
2919 			if (!ipv6_addr_any(&in6_dev->token)) {
2920 				read_lock_bh(&in6_dev->lock);
2921 				memcpy(addr.s6_addr + 8,
2922 				       in6_dev->token.s6_addr + 8, 8);
2923 				read_unlock_bh(&in6_dev->lock);
2924 				tokenized = true;
2925 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2926 				   !ipv6_generate_stable_address(&addr, 0,
2927 								 in6_dev)) {
2928 				addr_flags |= IFA_F_STABLE_PRIVACY;
2929 				goto ok;
2930 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2931 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2932 				goto put;
2933 			} else {
2934 				dev_addr_generated = true;
2935 			}
2936 			goto ok;
2937 		}
2938 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2939 				    pinfo->prefix_len);
2940 		goto put;
2941 
2942 ok:
2943 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2944 						   &addr, addr_type,
2945 						   addr_flags, sllao,
2946 						   tokenized, valid_lft,
2947 						   prefered_lft);
2948 		if (err)
2949 			goto put;
2950 
2951 		/* Ignore error case here because previous prefix add addr was
2952 		 * successful which will be notified.
2953 		 */
2954 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2955 					      addr_type, addr_flags, sllao,
2956 					      tokenized, valid_lft,
2957 					      prefered_lft,
2958 					      dev_addr_generated);
2959 	}
2960 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2961 put:
2962 	in6_dev_put(in6_dev);
2963 }
2964 
2965 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2966 		struct in6_ifreq *ireq)
2967 {
2968 	struct ip_tunnel_parm_kern p = { };
2969 	int err;
2970 
2971 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2972 		return -EADDRNOTAVAIL;
2973 
2974 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2975 	p.iph.version = 4;
2976 	p.iph.ihl = 5;
2977 	p.iph.protocol = IPPROTO_IPV6;
2978 	p.iph.ttl = 64;
2979 
2980 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2981 		return -EOPNOTSUPP;
2982 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2983 	if (err)
2984 		return err;
2985 
2986 	dev = __dev_get_by_name(net, p.name);
2987 	if (!dev)
2988 		return -ENOBUFS;
2989 	return dev_open(dev, NULL);
2990 }
2991 
2992 /*
2993  *	Set destination address.
2994  *	Special case for SIT interfaces where we create a new "virtual"
2995  *	device.
2996  */
2997 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2998 {
2999 	struct net_device *dev;
3000 	struct in6_ifreq ireq;
3001 	int err = -ENODEV;
3002 
3003 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
3004 		return -ENODEV;
3005 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3006 		return -EFAULT;
3007 
3008 	rtnl_net_lock(net);
3009 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3010 	if (dev && dev->type == ARPHRD_SIT)
3011 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
3012 	rtnl_net_unlock(net);
3013 	return err;
3014 }
3015 
3016 static int ipv6_mc_config(struct sock *sk, bool join,
3017 			  const struct in6_addr *addr, int ifindex)
3018 {
3019 	int ret;
3020 
3021 	ASSERT_RTNL();
3022 
3023 	lock_sock(sk);
3024 	if (join)
3025 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
3026 	else
3027 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
3028 	release_sock(sk);
3029 
3030 	return ret;
3031 }
3032 
3033 /*
3034  *	Manual configuration of address on an interface
3035  */
3036 static int inet6_addr_add(struct net *net, struct net_device *dev,
3037 			  struct ifa6_config *cfg, clock_t expires, u32 flags,
3038 			  struct netlink_ext_ack *extack)
3039 {
3040 	struct inet6_ifaddr *ifp;
3041 	struct inet6_dev *idev;
3042 
3043 	ASSERT_RTNL_NET(net);
3044 
3045 	if (cfg->plen > 128) {
3046 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3047 		return -EINVAL;
3048 	}
3049 
3050 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3051 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3052 		return -EINVAL;
3053 	}
3054 
3055 	idev = addrconf_add_dev(dev);
3056 	if (IS_ERR(idev)) {
3057 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3058 		return PTR_ERR(idev);
3059 	}
3060 
3061 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3062 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3063 					 true, cfg->pfx, dev->ifindex);
3064 
3065 		if (ret < 0) {
3066 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3067 			return ret;
3068 		}
3069 	}
3070 
3071 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3072 
3073 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3074 	if (!IS_ERR(ifp)) {
3075 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3076 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3077 					      ifp->rt_priority, dev, expires,
3078 					      flags, GFP_KERNEL);
3079 		}
3080 
3081 		/* Send a netlink notification if DAD is enabled and
3082 		 * optimistic flag is not set
3083 		 */
3084 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3085 			ipv6_ifa_notify(0, ifp);
3086 		/*
3087 		 * Note that section 3.1 of RFC 4429 indicates
3088 		 * that the Optimistic flag should not be set for
3089 		 * manually configured addresses
3090 		 */
3091 		addrconf_dad_start(ifp);
3092 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3093 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3094 					 cfg->preferred_lft, true, jiffies);
3095 		in6_ifa_put(ifp);
3096 		addrconf_verify_rtnl(net);
3097 		return 0;
3098 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3099 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3100 			       cfg->pfx, dev->ifindex);
3101 	}
3102 
3103 	return PTR_ERR(ifp);
3104 }
3105 
3106 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3107 			  const struct in6_addr *pfx, unsigned int plen,
3108 			  struct netlink_ext_ack *extack)
3109 {
3110 	struct inet6_ifaddr *ifp;
3111 	struct inet6_dev *idev;
3112 	struct net_device *dev;
3113 
3114 	if (plen > 128) {
3115 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3116 		return -EINVAL;
3117 	}
3118 
3119 	dev = __dev_get_by_index(net, ifindex);
3120 	if (!dev) {
3121 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3122 		return -ENODEV;
3123 	}
3124 
3125 	idev = __in6_dev_get_rtnl_net(dev);
3126 	if (!idev) {
3127 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3128 		return -ENXIO;
3129 	}
3130 
3131 	read_lock_bh(&idev->lock);
3132 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3133 		if (ifp->prefix_len == plen &&
3134 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3135 			in6_ifa_hold(ifp);
3136 			read_unlock_bh(&idev->lock);
3137 
3138 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3139 			    (ifp->flags & IFA_F_MANAGETEMPADDR))
3140 				delete_tempaddrs(idev, ifp);
3141 
3142 			ipv6_del_addr(ifp);
3143 
3144 			addrconf_verify_rtnl(net);
3145 			if (ipv6_addr_is_multicast(pfx)) {
3146 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3147 					       false, pfx, dev->ifindex);
3148 			}
3149 			return 0;
3150 		}
3151 	}
3152 	read_unlock_bh(&idev->lock);
3153 
3154 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3155 	return -EADDRNOTAVAIL;
3156 }
3157 
3158 
3159 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3160 {
3161 	struct ifa6_config cfg = {
3162 		.ifa_flags = IFA_F_PERMANENT,
3163 		.preferred_lft = INFINITY_LIFE_TIME,
3164 		.valid_lft = INFINITY_LIFE_TIME,
3165 	};
3166 	struct net_device *dev;
3167 	struct in6_ifreq ireq;
3168 	int err;
3169 
3170 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3171 		return -EPERM;
3172 
3173 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3174 		return -EFAULT;
3175 
3176 	cfg.pfx = &ireq.ifr6_addr;
3177 	cfg.plen = ireq.ifr6_prefixlen;
3178 
3179 	rtnl_net_lock(net);
3180 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3181 	if (dev) {
3182 		netdev_lock_ops(dev);
3183 		err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
3184 		netdev_unlock_ops(dev);
3185 	} else {
3186 		err = -ENODEV;
3187 	}
3188 	rtnl_net_unlock(net);
3189 	return err;
3190 }
3191 
3192 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3193 {
3194 	struct in6_ifreq ireq;
3195 	int err;
3196 
3197 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3198 		return -EPERM;
3199 
3200 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3201 		return -EFAULT;
3202 
3203 	rtnl_net_lock(net);
3204 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3205 			     ireq.ifr6_prefixlen, NULL);
3206 	rtnl_net_unlock(net);
3207 	return err;
3208 }
3209 
3210 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3211 		     int plen, int scope, u8 proto)
3212 {
3213 	struct inet6_ifaddr *ifp;
3214 	struct ifa6_config cfg = {
3215 		.pfx = addr,
3216 		.plen = plen,
3217 		.ifa_flags = IFA_F_PERMANENT,
3218 		.valid_lft = INFINITY_LIFE_TIME,
3219 		.preferred_lft = INFINITY_LIFE_TIME,
3220 		.scope = scope,
3221 		.ifa_proto = proto
3222 	};
3223 
3224 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3225 	if (!IS_ERR(ifp)) {
3226 		spin_lock_bh(&ifp->lock);
3227 		ifp->flags &= ~IFA_F_TENTATIVE;
3228 		spin_unlock_bh(&ifp->lock);
3229 		rt_genid_bump_ipv6(dev_net(idev->dev));
3230 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3231 		in6_ifa_put(ifp);
3232 	}
3233 }
3234 
3235 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE)
3236 static void add_v4_addrs(struct inet6_dev *idev)
3237 {
3238 	struct in6_addr addr;
3239 	struct net_device *dev;
3240 	struct net *net = dev_net(idev->dev);
3241 	int scope, plen;
3242 	u32 pflags = 0;
3243 
3244 	ASSERT_RTNL();
3245 
3246 	memset(&addr, 0, sizeof(struct in6_addr));
3247 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3248 
3249 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3250 		scope = IPV6_ADDR_COMPATv4;
3251 		plen = 96;
3252 		pflags |= RTF_NONEXTHOP;
3253 	} else {
3254 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3255 			return;
3256 
3257 		addr.s6_addr32[0] = htonl(0xfe800000);
3258 		scope = IFA_LINK;
3259 		plen = 64;
3260 	}
3261 
3262 	if (addr.s6_addr32[3]) {
3263 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3264 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3265 				      GFP_KERNEL);
3266 		return;
3267 	}
3268 
3269 	for_each_netdev(net, dev) {
3270 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3271 		if (in_dev && (dev->flags & IFF_UP)) {
3272 			struct in_ifaddr *ifa;
3273 			int flag = scope;
3274 
3275 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3276 				addr.s6_addr32[3] = ifa->ifa_local;
3277 
3278 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3279 					continue;
3280 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3281 					if (idev->dev->flags&IFF_POINTOPOINT)
3282 						continue;
3283 					flag |= IFA_HOST;
3284 				}
3285 
3286 				add_addr(idev, &addr, plen, flag,
3287 					 IFAPROT_UNSPEC);
3288 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3289 						      0, pflags, GFP_KERNEL);
3290 			}
3291 		}
3292 	}
3293 }
3294 #endif
3295 
3296 static void init_loopback(struct net_device *dev)
3297 {
3298 	struct inet6_dev  *idev;
3299 
3300 	/* ::1 */
3301 
3302 	ASSERT_RTNL();
3303 
3304 	idev = ipv6_find_idev(dev);
3305 	if (IS_ERR(idev)) {
3306 		pr_debug("%s: add_dev failed\n", __func__);
3307 		return;
3308 	}
3309 
3310 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3311 }
3312 
3313 void addrconf_add_linklocal(struct inet6_dev *idev,
3314 			    const struct in6_addr *addr, u32 flags)
3315 {
3316 	struct ifa6_config cfg = {
3317 		.pfx = addr,
3318 		.plen = 64,
3319 		.ifa_flags = flags | IFA_F_PERMANENT,
3320 		.valid_lft = INFINITY_LIFE_TIME,
3321 		.preferred_lft = INFINITY_LIFE_TIME,
3322 		.scope = IFA_LINK,
3323 		.ifa_proto = IFAPROT_KERNEL_LL
3324 	};
3325 	struct inet6_ifaddr *ifp;
3326 
3327 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3328 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3329 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3330 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3331 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3332 #endif
3333 
3334 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3335 	if (!IS_ERR(ifp)) {
3336 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3337 				      0, 0, GFP_ATOMIC);
3338 		addrconf_dad_start(ifp);
3339 		in6_ifa_put(ifp);
3340 	}
3341 }
3342 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3343 
3344 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3345 {
3346 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3347 		return true;
3348 
3349 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3350 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3351 		return true;
3352 
3353 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3354 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3355 		return true;
3356 
3357 	return false;
3358 }
3359 
3360 static int ipv6_generate_stable_address(struct in6_addr *address,
3361 					u8 dad_count,
3362 					const struct inet6_dev *idev)
3363 {
3364 	static DEFINE_SPINLOCK(lock);
3365 	static struct sha1_ctx sha_ctx;
3366 
3367 	static union {
3368 		u8 __data[SHA1_BLOCK_SIZE];
3369 		struct {
3370 			struct in6_addr secret;
3371 			__be32 prefix[2];
3372 			unsigned char hwaddr[MAX_ADDR_LEN];
3373 			u8 dad_count;
3374 		} __packed;
3375 	} data;
3376 
3377 	struct in6_addr secret;
3378 	struct in6_addr temp;
3379 	struct net *net = dev_net(idev->dev);
3380 
3381 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3382 
3383 	if (idev->cnf.stable_secret.initialized)
3384 		secret = idev->cnf.stable_secret.secret;
3385 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3386 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3387 	else
3388 		return -1;
3389 
3390 retry:
3391 	spin_lock_bh(&lock);
3392 
3393 	sha1_init(&sha_ctx);
3394 
3395 	memset(&data, 0, sizeof(data));
3396 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3397 	data.prefix[0] = address->s6_addr32[0];
3398 	data.prefix[1] = address->s6_addr32[1];
3399 	data.secret = secret;
3400 	data.dad_count = dad_count;
3401 
3402 	sha1_update(&sha_ctx, data.__data, sizeof(data));
3403 
3404 	/*
3405 	 * Note that the SHA-1 finalization is omitted here, and the digest is
3406 	 * pulled directly from the internal SHA-1 state (making it incompatible
3407 	 * with standard SHA-1).  Unusual, but technically okay since the data
3408 	 * length is fixed and is a multiple of the SHA-1 block size.
3409 	 */
3410 	temp = *address;
3411 	temp.s6_addr32[2] = (__force __be32)sha_ctx.state.h[0];
3412 	temp.s6_addr32[3] = (__force __be32)sha_ctx.state.h[1];
3413 
3414 	spin_unlock_bh(&lock);
3415 
3416 	if (ipv6_reserved_interfaceid(temp)) {
3417 		dad_count++;
3418 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3419 			return -1;
3420 		goto retry;
3421 	}
3422 
3423 	*address = temp;
3424 	return 0;
3425 }
3426 
3427 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3428 {
3429 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3430 
3431 	if (s->initialized)
3432 		return;
3433 	s = &idev->cnf.stable_secret;
3434 	get_random_bytes(&s->secret, sizeof(s->secret));
3435 	s->initialized = true;
3436 }
3437 
3438 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3439 {
3440 	struct in6_addr addr;
3441 
3442 	/* no link local addresses on L3 master devices */
3443 	if (netif_is_l3_master(idev->dev))
3444 		return;
3445 
3446 	/* no link local addresses on devices flagged as slaves */
3447 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3448 		return;
3449 
3450 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3451 
3452 	switch (idev->cnf.addr_gen_mode) {
3453 	case IN6_ADDR_GEN_MODE_RANDOM:
3454 		ipv6_gen_mode_random_init(idev);
3455 		fallthrough;
3456 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3457 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3458 			addrconf_add_linklocal(idev, &addr,
3459 					       IFA_F_STABLE_PRIVACY);
3460 		else if (prefix_route)
3461 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3462 					      0, 0, GFP_KERNEL);
3463 		break;
3464 	case IN6_ADDR_GEN_MODE_EUI64:
3465 		/* addrconf_add_linklocal also adds a prefix_route and we
3466 		 * only need to care about prefix routes if ipv6_generate_eui64
3467 		 * couldn't generate one.
3468 		 */
3469 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3470 			addrconf_add_linklocal(idev, &addr, 0);
3471 		else if (prefix_route)
3472 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3473 					      0, 0, GFP_KERNEL);
3474 		break;
3475 	case IN6_ADDR_GEN_MODE_NONE:
3476 	default:
3477 		/* will not add any link local address */
3478 		break;
3479 	}
3480 }
3481 
3482 static void addrconf_dev_config(struct net_device *dev)
3483 {
3484 	struct inet6_dev *idev;
3485 
3486 	ASSERT_RTNL();
3487 
3488 	if ((dev->type != ARPHRD_ETHER) &&
3489 	    (dev->type != ARPHRD_FDDI) &&
3490 	    (dev->type != ARPHRD_ARCNET) &&
3491 	    (dev->type != ARPHRD_INFINIBAND) &&
3492 	    (dev->type != ARPHRD_IEEE1394) &&
3493 	    (dev->type != ARPHRD_TUNNEL6) &&
3494 	    (dev->type != ARPHRD_6LOWPAN) &&
3495 	    (dev->type != ARPHRD_IP6GRE) &&
3496 	    (dev->type != ARPHRD_TUNNEL) &&
3497 	    (dev->type != ARPHRD_NONE) &&
3498 	    (dev->type != ARPHRD_RAWIP)) {
3499 		/* Alas, we support only Ethernet autoconfiguration. */
3500 		idev = __in6_dev_get(dev);
3501 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3502 		    dev->flags & IFF_MULTICAST)
3503 			ipv6_mc_up(idev);
3504 		return;
3505 	}
3506 
3507 	idev = addrconf_add_dev(dev);
3508 	if (IS_ERR(idev))
3509 		return;
3510 
3511 	/* this device type has no EUI support */
3512 	if (dev->type == ARPHRD_NONE &&
3513 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3514 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3515 			   IN6_ADDR_GEN_MODE_RANDOM);
3516 
3517 	addrconf_addr_gen(idev, false);
3518 }
3519 
3520 #if IS_ENABLED(CONFIG_IPV6_SIT)
3521 static void addrconf_sit_config(struct net_device *dev)
3522 {
3523 	struct inet6_dev *idev;
3524 
3525 	ASSERT_RTNL();
3526 
3527 	/*
3528 	 * Configure the tunnel with one of our IPv4
3529 	 * addresses... we should configure all of
3530 	 * our v4 addrs in the tunnel
3531 	 */
3532 
3533 	idev = ipv6_find_idev(dev);
3534 	if (IS_ERR(idev)) {
3535 		pr_debug("%s: add_dev failed\n", __func__);
3536 		return;
3537 	}
3538 
3539 	if (dev->priv_flags & IFF_ISATAP) {
3540 		addrconf_addr_gen(idev, false);
3541 		return;
3542 	}
3543 
3544 	add_v4_addrs(idev);
3545 
3546 	if (dev->flags&IFF_POINTOPOINT)
3547 		addrconf_add_mroute(dev);
3548 }
3549 #endif
3550 
3551 #if IS_ENABLED(CONFIG_NET_IPGRE)
3552 static void addrconf_gre_config(struct net_device *dev)
3553 {
3554 	struct inet6_dev *idev;
3555 
3556 	ASSERT_RTNL();
3557 
3558 	idev = addrconf_add_dev(dev);
3559 	if (IS_ERR(idev))
3560 		return;
3561 
3562 	/* Generate the IPv6 link-local address using addrconf_addr_gen(),
3563 	 * unless we have an IPv4 GRE device not bound to an IP address and
3564 	 * which is in EUI64 mode (as __ipv6_isatap_ifid() would fail in this
3565 	 * case). Such devices fall back to add_v4_addrs() instead.
3566 	 */
3567 	if (!(*(__be32 *)dev->dev_addr == 0 &&
3568 	      idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)) {
3569 		addrconf_addr_gen(idev, true);
3570 		return;
3571 	}
3572 
3573 	add_v4_addrs(idev);
3574 }
3575 #endif
3576 
3577 static void addrconf_init_auto_addrs(struct net_device *dev)
3578 {
3579 	switch (dev->type) {
3580 #if IS_ENABLED(CONFIG_IPV6_SIT)
3581 	case ARPHRD_SIT:
3582 		addrconf_sit_config(dev);
3583 		break;
3584 #endif
3585 #if IS_ENABLED(CONFIG_NET_IPGRE)
3586 	case ARPHRD_IPGRE:
3587 		addrconf_gre_config(dev);
3588 		break;
3589 #endif
3590 	case ARPHRD_LOOPBACK:
3591 		init_loopback(dev);
3592 		break;
3593 
3594 	default:
3595 		addrconf_dev_config(dev);
3596 		break;
3597 	}
3598 }
3599 
3600 static int fixup_permanent_addr(struct net *net,
3601 				struct inet6_dev *idev,
3602 				struct inet6_ifaddr *ifp)
3603 {
3604 	/* !fib6_node means the host route was removed from the
3605 	 * FIB, for example, if 'lo' device is taken down. In that
3606 	 * case regenerate the host route.
3607 	 */
3608 	if (!ifp->rt || !ifp->rt->fib6_node) {
3609 		struct fib6_info *f6i, *prev;
3610 
3611 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3612 					 GFP_KERNEL, NULL);
3613 		if (IS_ERR(f6i))
3614 			return PTR_ERR(f6i);
3615 
3616 		/* ifp->rt can be accessed outside of rtnl */
3617 		spin_lock_bh(&ifp->lock);
3618 		prev = ifp->rt;
3619 		ifp->rt = f6i;
3620 		spin_unlock_bh(&ifp->lock);
3621 
3622 		fib6_info_release(prev);
3623 	}
3624 
3625 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3626 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3627 				      ifp->rt_priority, idev->dev, 0, 0,
3628 				      GFP_KERNEL);
3629 	}
3630 
3631 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3632 		addrconf_dad_start(ifp);
3633 
3634 	return 0;
3635 }
3636 
3637 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3638 {
3639 	struct inet6_ifaddr *ifp;
3640 	LIST_HEAD(tmp_addr_list);
3641 	struct inet6_dev *idev;
3642 
3643 	/* Mutual exclusion with other if_list_aux users. */
3644 	ASSERT_RTNL();
3645 
3646 	idev = __in6_dev_get(dev);
3647 	if (!idev)
3648 		return;
3649 
3650 	write_lock_bh(&idev->lock);
3651 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3652 		if (ifp->flags & IFA_F_PERMANENT)
3653 			list_add_tail(&ifp->if_list_aux, &tmp_addr_list);
3654 	}
3655 	write_unlock_bh(&idev->lock);
3656 
3657 	while (!list_empty(&tmp_addr_list)) {
3658 		ifp = list_first_entry(&tmp_addr_list,
3659 				       struct inet6_ifaddr, if_list_aux);
3660 		list_del(&ifp->if_list_aux);
3661 
3662 		if (fixup_permanent_addr(net, idev, ifp) < 0) {
3663 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3664 					     idev->dev->name, &ifp->addr);
3665 			in6_ifa_hold(ifp);
3666 			ipv6_del_addr(ifp);
3667 		}
3668 	}
3669 }
3670 
3671 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3672 			   void *ptr)
3673 {
3674 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3675 	struct netdev_notifier_change_info *change_info;
3676 	struct netdev_notifier_changeupper_info *info;
3677 	struct inet6_dev *idev = __in6_dev_get(dev);
3678 	struct net *net = dev_net(dev);
3679 	int run_pending = 0;
3680 	int err;
3681 
3682 	switch (event) {
3683 	case NETDEV_REGISTER:
3684 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3685 			idev = ipv6_add_dev(dev);
3686 			if (IS_ERR(idev))
3687 				return notifier_from_errno(PTR_ERR(idev));
3688 		}
3689 		break;
3690 
3691 	case NETDEV_CHANGEMTU:
3692 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3693 		if (dev->mtu < IPV6_MIN_MTU) {
3694 			addrconf_ifdown(dev, dev != net->loopback_dev);
3695 			break;
3696 		}
3697 
3698 		if (idev) {
3699 			rt6_mtu_change(dev, dev->mtu);
3700 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3701 			break;
3702 		}
3703 
3704 		/* allocate new idev */
3705 		idev = ipv6_add_dev(dev);
3706 		if (IS_ERR(idev))
3707 			break;
3708 
3709 		/* device is still not ready */
3710 		if (!(idev->if_flags & IF_READY))
3711 			break;
3712 
3713 		run_pending = 1;
3714 		fallthrough;
3715 	case NETDEV_UP:
3716 	case NETDEV_CHANGE:
3717 		if (idev && idev->cnf.disable_ipv6)
3718 			break;
3719 
3720 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3721 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3722 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3723 				ipv6_mc_up(idev);
3724 			break;
3725 		}
3726 
3727 		if (event == NETDEV_UP) {
3728 			/* restore routes for permanent addresses */
3729 			addrconf_permanent_addr(net, dev);
3730 
3731 			if (!addrconf_link_ready(dev)) {
3732 				/* device is not ready yet. */
3733 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3734 					 dev->name);
3735 				break;
3736 			}
3737 
3738 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3739 				idev = ipv6_add_dev(dev);
3740 
3741 			if (!IS_ERR_OR_NULL(idev)) {
3742 				idev->if_flags |= IF_READY;
3743 				run_pending = 1;
3744 			}
3745 		} else if (event == NETDEV_CHANGE) {
3746 			if (!addrconf_link_ready(dev)) {
3747 				/* device is still not ready. */
3748 				rt6_sync_down_dev(dev, event);
3749 				break;
3750 			}
3751 
3752 			if (!IS_ERR_OR_NULL(idev)) {
3753 				if (idev->if_flags & IF_READY) {
3754 					/* device is already configured -
3755 					 * but resend MLD reports, we might
3756 					 * have roamed and need to update
3757 					 * multicast snooping switches
3758 					 */
3759 					ipv6_mc_up(idev);
3760 					change_info = ptr;
3761 					if (change_info->flags_changed & IFF_NOARP)
3762 						addrconf_dad_run(idev, true);
3763 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3764 					break;
3765 				}
3766 				idev->if_flags |= IF_READY;
3767 			}
3768 
3769 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3770 				 dev->name);
3771 
3772 			run_pending = 1;
3773 		}
3774 
3775 		addrconf_init_auto_addrs(dev);
3776 
3777 		if (!IS_ERR_OR_NULL(idev)) {
3778 			if (run_pending)
3779 				addrconf_dad_run(idev, false);
3780 
3781 			/* Device has an address by now */
3782 			rt6_sync_up(dev, RTNH_F_DEAD);
3783 
3784 			/*
3785 			 * If the MTU changed during the interface down,
3786 			 * when the interface up, the changed MTU must be
3787 			 * reflected in the idev as well as routers.
3788 			 */
3789 			if (idev->cnf.mtu6 != dev->mtu &&
3790 			    dev->mtu >= IPV6_MIN_MTU) {
3791 				rt6_mtu_change(dev, dev->mtu);
3792 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3793 			}
3794 			WRITE_ONCE(idev->tstamp, jiffies);
3795 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3796 
3797 			/*
3798 			 * If the changed mtu during down is lower than
3799 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3800 			 */
3801 			if (dev->mtu < IPV6_MIN_MTU)
3802 				addrconf_ifdown(dev, dev != net->loopback_dev);
3803 		}
3804 		break;
3805 
3806 	case NETDEV_DOWN:
3807 	case NETDEV_UNREGISTER:
3808 		/*
3809 		 *	Remove all addresses from this interface.
3810 		 */
3811 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3812 		break;
3813 
3814 	case NETDEV_CHANGENAME:
3815 		if (idev) {
3816 			snmp6_unregister_dev(idev);
3817 			addrconf_sysctl_unregister(idev);
3818 			err = addrconf_sysctl_register(idev);
3819 			if (err)
3820 				return notifier_from_errno(err);
3821 			err = snmp6_register_dev(idev);
3822 			if (err) {
3823 				addrconf_sysctl_unregister(idev);
3824 				return notifier_from_errno(err);
3825 			}
3826 		}
3827 		break;
3828 
3829 	case NETDEV_PRE_TYPE_CHANGE:
3830 	case NETDEV_POST_TYPE_CHANGE:
3831 		if (idev)
3832 			addrconf_type_change(dev, event);
3833 		break;
3834 
3835 	case NETDEV_CHANGEUPPER:
3836 		info = ptr;
3837 
3838 		/* flush all routes if dev is linked to or unlinked from
3839 		 * an L3 master device (e.g., VRF)
3840 		 */
3841 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3842 			addrconf_ifdown(dev, false);
3843 	}
3844 
3845 	return NOTIFY_OK;
3846 }
3847 
3848 /*
3849  *	addrconf module should be notified of a device going up
3850  */
3851 static struct notifier_block ipv6_dev_notf = {
3852 	.notifier_call = addrconf_notify,
3853 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3854 };
3855 
3856 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3857 {
3858 	struct inet6_dev *idev;
3859 	ASSERT_RTNL();
3860 
3861 	idev = __in6_dev_get(dev);
3862 
3863 	if (event == NETDEV_POST_TYPE_CHANGE)
3864 		ipv6_mc_remap(idev);
3865 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3866 		ipv6_mc_unmap(idev);
3867 }
3868 
3869 static bool addr_is_local(const struct in6_addr *addr)
3870 {
3871 	return ipv6_addr_type(addr) &
3872 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3873 }
3874 
3875 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3876 {
3877 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3878 	struct net *net = dev_net(dev);
3879 	struct inet6_dev *idev;
3880 	struct inet6_ifaddr *ifa;
3881 	LIST_HEAD(tmp_addr_list);
3882 	bool keep_addr = false;
3883 	bool was_ready;
3884 	int state, i;
3885 
3886 	ASSERT_RTNL();
3887 
3888 	rt6_disable_ip(dev, event);
3889 
3890 	idev = __in6_dev_get(dev);
3891 	if (!idev)
3892 		return -ENODEV;
3893 
3894 	/*
3895 	 * Step 1: remove reference to ipv6 device from parent device.
3896 	 *	   Do not dev_put!
3897 	 */
3898 	if (unregister) {
3899 		WRITE_ONCE(idev->dead, 1);
3900 
3901 		/* protected by rtnl_lock */
3902 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3903 
3904 		/* Step 1.5: remove snmp6 entry */
3905 		snmp6_unregister_dev(idev);
3906 
3907 	}
3908 
3909 	/* combine the user config with event to determine if permanent
3910 	 * addresses are to be removed from address hash table
3911 	 */
3912 	if (!unregister && !idev->cnf.disable_ipv6) {
3913 		/* aggregate the system setting and interface setting */
3914 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3915 
3916 		if (!_keep_addr)
3917 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3918 
3919 		keep_addr = (_keep_addr > 0);
3920 	}
3921 
3922 	/* Step 2: clear hash table */
3923 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3924 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3925 
3926 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3927 restart:
3928 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3929 			if (ifa->idev == idev) {
3930 				addrconf_del_dad_work(ifa);
3931 				/* combined flag + permanent flag decide if
3932 				 * address is retained on a down event
3933 				 */
3934 				if (!keep_addr ||
3935 				    !(ifa->flags & IFA_F_PERMANENT) ||
3936 				    addr_is_local(&ifa->addr)) {
3937 					hlist_del_init_rcu(&ifa->addr_lst);
3938 					goto restart;
3939 				}
3940 			}
3941 		}
3942 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3943 	}
3944 
3945 	write_lock_bh(&idev->lock);
3946 
3947 	addrconf_del_rs_timer(idev);
3948 
3949 	/* Step 2: clear flags for stateless addrconf, repeated down
3950 	 *         detection
3951 	 */
3952 	was_ready = idev->if_flags & IF_READY;
3953 	if (!unregister)
3954 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3955 
3956 	/* Step 3: clear tempaddr list */
3957 	while (!list_empty(&idev->tempaddr_list)) {
3958 		ifa = list_first_entry(&idev->tempaddr_list,
3959 				       struct inet6_ifaddr, tmp_list);
3960 		list_del(&ifa->tmp_list);
3961 		write_unlock_bh(&idev->lock);
3962 		spin_lock_bh(&ifa->lock);
3963 
3964 		if (ifa->ifpub) {
3965 			in6_ifa_put(ifa->ifpub);
3966 			ifa->ifpub = NULL;
3967 		}
3968 		spin_unlock_bh(&ifa->lock);
3969 		in6_ifa_put(ifa);
3970 		write_lock_bh(&idev->lock);
3971 	}
3972 
3973 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3974 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3975 	write_unlock_bh(&idev->lock);
3976 
3977 	while (!list_empty(&tmp_addr_list)) {
3978 		struct fib6_info *rt = NULL;
3979 		bool keep;
3980 
3981 		ifa = list_first_entry(&tmp_addr_list,
3982 				       struct inet6_ifaddr, if_list_aux);
3983 		list_del(&ifa->if_list_aux);
3984 
3985 		addrconf_del_dad_work(ifa);
3986 
3987 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3988 			!addr_is_local(&ifa->addr);
3989 
3990 		spin_lock_bh(&ifa->lock);
3991 
3992 		if (keep) {
3993 			/* set state to skip the notifier below */
3994 			state = INET6_IFADDR_STATE_DEAD;
3995 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3996 			if (!(ifa->flags & IFA_F_NODAD))
3997 				ifa->flags |= IFA_F_TENTATIVE;
3998 
3999 			rt = ifa->rt;
4000 			ifa->rt = NULL;
4001 		} else {
4002 			state = ifa->state;
4003 			ifa->state = INET6_IFADDR_STATE_DEAD;
4004 		}
4005 
4006 		spin_unlock_bh(&ifa->lock);
4007 
4008 		if (rt)
4009 			ip6_del_rt(net, rt, false);
4010 
4011 		if (state != INET6_IFADDR_STATE_DEAD) {
4012 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
4013 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
4014 		} else {
4015 			if (idev->cnf.forwarding)
4016 				addrconf_leave_anycast(ifa);
4017 			addrconf_leave_solict(ifa->idev, &ifa->addr);
4018 		}
4019 
4020 		if (!keep) {
4021 			write_lock_bh(&idev->lock);
4022 			list_del_rcu(&ifa->if_list);
4023 			write_unlock_bh(&idev->lock);
4024 			in6_ifa_put(ifa);
4025 		}
4026 	}
4027 
4028 	/* Step 5: Discard anycast and multicast list */
4029 	if (unregister) {
4030 		ipv6_ac_destroy_dev(idev);
4031 		ipv6_mc_destroy_dev(idev);
4032 	} else if (was_ready) {
4033 		ipv6_mc_down(idev);
4034 	}
4035 
4036 	WRITE_ONCE(idev->tstamp, jiffies);
4037 	idev->ra_mtu = 0;
4038 
4039 	/* Last: Shot the device (if unregistered) */
4040 	if (unregister) {
4041 		addrconf_sysctl_unregister(idev);
4042 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4043 		neigh_ifdown(&nd_tbl, dev);
4044 		in6_dev_put(idev);
4045 	}
4046 	return 0;
4047 }
4048 
4049 static void addrconf_rs_timer(struct timer_list *t)
4050 {
4051 	struct inet6_dev *idev = timer_container_of(idev, t, rs_timer);
4052 	struct net_device *dev = idev->dev;
4053 	struct in6_addr lladdr;
4054 	int rtr_solicits;
4055 
4056 	write_lock(&idev->lock);
4057 	if (idev->dead || !(idev->if_flags & IF_READY))
4058 		goto out;
4059 
4060 	if (!ipv6_accept_ra(idev))
4061 		goto out;
4062 
4063 	/* Announcement received after solicitation was sent */
4064 	if (idev->if_flags & IF_RA_RCVD)
4065 		goto out;
4066 
4067 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4068 
4069 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4070 		write_unlock(&idev->lock);
4071 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4072 			ndisc_send_rs(dev, &lladdr,
4073 				      &in6addr_linklocal_allrouters);
4074 		else
4075 			goto put;
4076 
4077 		write_lock(&idev->lock);
4078 		idev->rs_interval = rfc3315_s14_backoff_update(
4079 				idev->rs_interval,
4080 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4081 		/* The wait after the last probe can be shorter */
4082 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4083 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4084 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4085 				      idev->rs_interval);
4086 	} else {
4087 		/*
4088 		 * Note: we do not support deprecated "all on-link"
4089 		 * assumption any longer.
4090 		 */
4091 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4092 	}
4093 
4094 out:
4095 	write_unlock(&idev->lock);
4096 put:
4097 	in6_dev_put(idev);
4098 }
4099 
4100 /*
4101  *	Duplicate Address Detection
4102  */
4103 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4104 {
4105 	struct inet6_dev *idev = ifp->idev;
4106 	unsigned long rand_num;
4107 	u64 nonce;
4108 
4109 	if (ifp->flags & IFA_F_OPTIMISTIC)
4110 		rand_num = 0;
4111 	else
4112 		rand_num = get_random_u32_below(
4113 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4114 
4115 	nonce = 0;
4116 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4117 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4118 		do
4119 			get_random_bytes(&nonce, 6);
4120 		while (nonce == 0);
4121 	}
4122 	ifp->dad_nonce = nonce;
4123 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4124 	addrconf_mod_dad_work(ifp, rand_num);
4125 }
4126 
4127 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4128 {
4129 	struct inet6_dev *idev = ifp->idev;
4130 	struct net_device *dev = idev->dev;
4131 	bool bump_id, notify = false;
4132 	struct net *net;
4133 
4134 	addrconf_join_solict(dev, &ifp->addr);
4135 
4136 	read_lock_bh(&idev->lock);
4137 	spin_lock(&ifp->lock);
4138 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4139 		goto out;
4140 
4141 	net = dev_net(dev);
4142 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4143 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4144 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4145 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4146 	    ifp->flags & IFA_F_NODAD) {
4147 		bool send_na = false;
4148 
4149 		if (ifp->flags & IFA_F_TENTATIVE &&
4150 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4151 			send_na = true;
4152 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4153 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4154 		spin_unlock(&ifp->lock);
4155 		read_unlock_bh(&idev->lock);
4156 
4157 		addrconf_dad_completed(ifp, bump_id, send_na);
4158 		return;
4159 	}
4160 
4161 	if (!(idev->if_flags & IF_READY)) {
4162 		spin_unlock(&ifp->lock);
4163 		read_unlock_bh(&idev->lock);
4164 		/*
4165 		 * If the device is not ready:
4166 		 * - keep it tentative if it is a permanent address.
4167 		 * - otherwise, kill it.
4168 		 */
4169 		in6_ifa_hold(ifp);
4170 		addrconf_dad_stop(ifp, 0);
4171 		return;
4172 	}
4173 
4174 	/*
4175 	 * Optimistic nodes can start receiving
4176 	 * Frames right away
4177 	 */
4178 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4179 		ip6_ins_rt(net, ifp->rt);
4180 		if (ipv6_use_optimistic_addr(net, idev)) {
4181 			/* Because optimistic nodes can use this address,
4182 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4183 			 */
4184 			notify = true;
4185 		}
4186 	}
4187 
4188 	addrconf_dad_kick(ifp);
4189 out:
4190 	spin_unlock(&ifp->lock);
4191 	read_unlock_bh(&idev->lock);
4192 	if (notify)
4193 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4194 }
4195 
4196 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4197 {
4198 	bool begin_dad = false;
4199 
4200 	spin_lock_bh(&ifp->lock);
4201 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4202 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4203 		begin_dad = true;
4204 	}
4205 	spin_unlock_bh(&ifp->lock);
4206 
4207 	if (begin_dad)
4208 		addrconf_mod_dad_work(ifp, 0);
4209 }
4210 
4211 static void addrconf_dad_work(struct work_struct *w)
4212 {
4213 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4214 						struct inet6_ifaddr,
4215 						dad_work);
4216 	struct inet6_dev *idev = ifp->idev;
4217 	bool bump_id, disable_ipv6 = false;
4218 	struct in6_addr mcaddr;
4219 	struct net *net;
4220 
4221 	enum {
4222 		DAD_PROCESS,
4223 		DAD_BEGIN,
4224 		DAD_ABORT,
4225 	} action = DAD_PROCESS;
4226 
4227 	net = dev_net(idev->dev);
4228 
4229 	rtnl_net_lock(net);
4230 
4231 	spin_lock_bh(&ifp->lock);
4232 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4233 		action = DAD_BEGIN;
4234 		ifp->state = INET6_IFADDR_STATE_DAD;
4235 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4236 		action = DAD_ABORT;
4237 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4238 
4239 		if ((READ_ONCE(net->ipv6.devconf_all->accept_dad) > 1 ||
4240 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4241 		    !idev->cnf.disable_ipv6 &&
4242 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4243 			struct in6_addr addr;
4244 
4245 			addr.s6_addr32[0] = htonl(0xfe800000);
4246 			addr.s6_addr32[1] = 0;
4247 
4248 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4249 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4250 				/* DAD failed for link-local based on MAC */
4251 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4252 
4253 				pr_info("%s: IPv6 being disabled!\n",
4254 					ifp->idev->dev->name);
4255 				disable_ipv6 = true;
4256 			}
4257 		}
4258 	}
4259 	spin_unlock_bh(&ifp->lock);
4260 
4261 	if (action == DAD_BEGIN) {
4262 		addrconf_dad_begin(ifp);
4263 		goto out;
4264 	} else if (action == DAD_ABORT) {
4265 		in6_ifa_hold(ifp);
4266 		addrconf_dad_stop(ifp, 1);
4267 		if (disable_ipv6)
4268 			addrconf_ifdown(idev->dev, false);
4269 		goto out;
4270 	}
4271 
4272 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4273 		goto out;
4274 
4275 	write_lock_bh(&idev->lock);
4276 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4277 		write_unlock_bh(&idev->lock);
4278 		goto out;
4279 	}
4280 
4281 	spin_lock(&ifp->lock);
4282 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4283 		spin_unlock(&ifp->lock);
4284 		write_unlock_bh(&idev->lock);
4285 		goto out;
4286 	}
4287 
4288 	if (ifp->dad_probes == 0) {
4289 		bool send_na = false;
4290 
4291 		/*
4292 		 * DAD was successful
4293 		 */
4294 
4295 		if (ifp->flags & IFA_F_TENTATIVE &&
4296 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4297 			send_na = true;
4298 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4299 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4300 		spin_unlock(&ifp->lock);
4301 		write_unlock_bh(&idev->lock);
4302 
4303 		addrconf_dad_completed(ifp, bump_id, send_na);
4304 
4305 		goto out;
4306 	}
4307 
4308 	ifp->dad_probes--;
4309 	addrconf_mod_dad_work(ifp,
4310 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4311 				  HZ/100));
4312 	spin_unlock(&ifp->lock);
4313 	write_unlock_bh(&idev->lock);
4314 
4315 	/* send a neighbour solicitation for our addr */
4316 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4317 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4318 		      ifp->dad_nonce);
4319 out:
4320 	in6_ifa_put(ifp);
4321 	rtnl_net_unlock(net);
4322 }
4323 
4324 /* ifp->idev must be at least read locked */
4325 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4326 {
4327 	struct inet6_ifaddr *ifpiter;
4328 	struct inet6_dev *idev = ifp->idev;
4329 
4330 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4331 		if (ifpiter->scope > IFA_LINK)
4332 			break;
4333 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4334 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4335 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4336 		    IFA_F_PERMANENT)
4337 			return false;
4338 	}
4339 	return true;
4340 }
4341 
4342 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4343 				   bool send_na)
4344 {
4345 	struct net_device *dev = ifp->idev->dev;
4346 	struct in6_addr lladdr;
4347 	bool send_rs, send_mld;
4348 
4349 	addrconf_del_dad_work(ifp);
4350 
4351 	/*
4352 	 *	Configure the address for reception. Now it is valid.
4353 	 */
4354 
4355 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4356 
4357 	/* If added prefix is link local and we are prepared to process
4358 	   router advertisements, start sending router solicitations.
4359 	 */
4360 
4361 	read_lock_bh(&ifp->idev->lock);
4362 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4363 	send_rs = send_mld &&
4364 		  ipv6_accept_ra(ifp->idev) &&
4365 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4366 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4367 		  (dev->type != ARPHRD_TUNNEL) &&
4368 		  !netif_is_team_port(dev);
4369 	read_unlock_bh(&ifp->idev->lock);
4370 
4371 	/* While dad is in progress mld report's source address is in6_addrany.
4372 	 * Resend with proper ll now.
4373 	 */
4374 	if (send_mld)
4375 		ipv6_mc_dad_complete(ifp->idev);
4376 
4377 	/* send unsolicited NA if enabled */
4378 	if (send_na &&
4379 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4380 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4381 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4382 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4383 			      /*solicited=*/ false, /*override=*/ true,
4384 			      /*inc_opt=*/ true);
4385 	}
4386 
4387 	if (send_rs) {
4388 		/*
4389 		 *	If a host as already performed a random delay
4390 		 *	[...] as part of DAD [...] there is no need
4391 		 *	to delay again before sending the first RS
4392 		 */
4393 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4394 			return;
4395 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4396 
4397 		write_lock_bh(&ifp->idev->lock);
4398 		spin_lock(&ifp->lock);
4399 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4400 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4401 		ifp->idev->rs_probes = 1;
4402 		ifp->idev->if_flags |= IF_RS_SENT;
4403 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4404 		spin_unlock(&ifp->lock);
4405 		write_unlock_bh(&ifp->idev->lock);
4406 	}
4407 
4408 	if (bump_id)
4409 		rt_genid_bump_ipv6(dev_net(dev));
4410 
4411 	/* Make sure that a new temporary address will be created
4412 	 * before this temporary address becomes deprecated.
4413 	 */
4414 	if (ifp->flags & IFA_F_TEMPORARY)
4415 		addrconf_verify_rtnl(dev_net(dev));
4416 }
4417 
4418 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4419 {
4420 	struct inet6_ifaddr *ifp;
4421 
4422 	read_lock_bh(&idev->lock);
4423 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4424 		spin_lock(&ifp->lock);
4425 		if ((ifp->flags & IFA_F_TENTATIVE &&
4426 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4427 			if (restart)
4428 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4429 			addrconf_dad_kick(ifp);
4430 		}
4431 		spin_unlock(&ifp->lock);
4432 	}
4433 	read_unlock_bh(&idev->lock);
4434 }
4435 
4436 #ifdef CONFIG_PROC_FS
4437 struct if6_iter_state {
4438 	struct seq_net_private p;
4439 	int bucket;
4440 	int offset;
4441 };
4442 
4443 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4444 {
4445 	struct if6_iter_state *state = seq->private;
4446 	struct net *net = seq_file_net(seq);
4447 	struct inet6_ifaddr *ifa = NULL;
4448 	int p = 0;
4449 
4450 	/* initial bucket if pos is 0 */
4451 	if (pos == 0) {
4452 		state->bucket = 0;
4453 		state->offset = 0;
4454 	}
4455 
4456 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4457 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4458 					 addr_lst) {
4459 			/* sync with offset */
4460 			if (p < state->offset) {
4461 				p++;
4462 				continue;
4463 			}
4464 			return ifa;
4465 		}
4466 
4467 		/* prepare for next bucket */
4468 		state->offset = 0;
4469 		p = 0;
4470 	}
4471 	return NULL;
4472 }
4473 
4474 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4475 					 struct inet6_ifaddr *ifa)
4476 {
4477 	struct if6_iter_state *state = seq->private;
4478 	struct net *net = seq_file_net(seq);
4479 
4480 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4481 		state->offset++;
4482 		return ifa;
4483 	}
4484 
4485 	state->offset = 0;
4486 	while (++state->bucket < IN6_ADDR_HSIZE) {
4487 		hlist_for_each_entry_rcu(ifa,
4488 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4489 			return ifa;
4490 		}
4491 	}
4492 
4493 	return NULL;
4494 }
4495 
4496 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4497 	__acquires(rcu)
4498 {
4499 	rcu_read_lock();
4500 	return if6_get_first(seq, *pos);
4501 }
4502 
4503 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4504 {
4505 	struct inet6_ifaddr *ifa;
4506 
4507 	ifa = if6_get_next(seq, v);
4508 	++*pos;
4509 	return ifa;
4510 }
4511 
4512 static void if6_seq_stop(struct seq_file *seq, void *v)
4513 	__releases(rcu)
4514 {
4515 	rcu_read_unlock();
4516 }
4517 
4518 static int if6_seq_show(struct seq_file *seq, void *v)
4519 {
4520 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4521 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4522 		   &ifp->addr,
4523 		   ifp->idev->dev->ifindex,
4524 		   ifp->prefix_len,
4525 		   ifp->scope,
4526 		   (u8) ifp->flags,
4527 		   ifp->idev->dev->name);
4528 	return 0;
4529 }
4530 
4531 static const struct seq_operations if6_seq_ops = {
4532 	.start	= if6_seq_start,
4533 	.next	= if6_seq_next,
4534 	.show	= if6_seq_show,
4535 	.stop	= if6_seq_stop,
4536 };
4537 
4538 static int __net_init if6_proc_net_init(struct net *net)
4539 {
4540 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4541 			sizeof(struct if6_iter_state)))
4542 		return -ENOMEM;
4543 	return 0;
4544 }
4545 
4546 static void __net_exit if6_proc_net_exit(struct net *net)
4547 {
4548 	remove_proc_entry("if_inet6", net->proc_net);
4549 }
4550 
4551 static struct pernet_operations if6_proc_net_ops = {
4552 	.init = if6_proc_net_init,
4553 	.exit = if6_proc_net_exit,
4554 };
4555 
4556 int __init if6_proc_init(void)
4557 {
4558 	return register_pernet_subsys(&if6_proc_net_ops);
4559 }
4560 
4561 void if6_proc_exit(void)
4562 {
4563 	unregister_pernet_subsys(&if6_proc_net_ops);
4564 }
4565 #endif	/* CONFIG_PROC_FS */
4566 
4567 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4568 /* Check if address is a home address configured on any interface. */
4569 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4570 {
4571 	unsigned int hash = inet6_addr_hash(net, addr);
4572 	struct inet6_ifaddr *ifp = NULL;
4573 	int ret = 0;
4574 
4575 	rcu_read_lock();
4576 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4577 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4578 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4579 			ret = 1;
4580 			break;
4581 		}
4582 	}
4583 	rcu_read_unlock();
4584 	return ret;
4585 }
4586 #endif
4587 
4588 /* RFC6554 has some algorithm to avoid loops in segment routing by
4589  * checking if the segments contains any of a local interface address.
4590  *
4591  * Quote:
4592  *
4593  * To detect loops in the SRH, a router MUST determine if the SRH
4594  * includes multiple addresses assigned to any interface on that router.
4595  * If such addresses appear more than once and are separated by at least
4596  * one address not assigned to that router.
4597  */
4598 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4599 			  unsigned char nsegs)
4600 {
4601 	const struct in6_addr *addr;
4602 	int i, ret = 0, found = 0;
4603 	struct inet6_ifaddr *ifp;
4604 	bool separated = false;
4605 	unsigned int hash;
4606 	bool hash_found;
4607 
4608 	rcu_read_lock();
4609 	for (i = 0; i < nsegs; i++) {
4610 		addr = &segs[i];
4611 		hash = inet6_addr_hash(net, addr);
4612 
4613 		hash_found = false;
4614 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4615 
4616 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4617 				hash_found = true;
4618 				break;
4619 			}
4620 		}
4621 
4622 		if (hash_found) {
4623 			if (found > 1 && separated) {
4624 				ret = 1;
4625 				break;
4626 			}
4627 
4628 			separated = false;
4629 			found++;
4630 		} else {
4631 			separated = true;
4632 		}
4633 	}
4634 	rcu_read_unlock();
4635 
4636 	return ret;
4637 }
4638 
4639 /*
4640  *	Periodic address status verification
4641  */
4642 
4643 static void addrconf_verify_rtnl(struct net *net)
4644 {
4645 	unsigned long now, next, next_sec, next_sched;
4646 	struct inet6_ifaddr *ifp;
4647 	int i;
4648 
4649 	ASSERT_RTNL();
4650 
4651 	rcu_read_lock_bh();
4652 	now = jiffies;
4653 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4654 
4655 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4656 
4657 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4658 restart:
4659 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4660 			unsigned long age;
4661 
4662 			/* When setting preferred_lft to a value not zero or
4663 			 * infinity, while valid_lft is infinity
4664 			 * IFA_F_PERMANENT has a non-infinity life time.
4665 			 */
4666 			if ((ifp->flags & IFA_F_PERMANENT) &&
4667 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4668 				continue;
4669 
4670 			spin_lock(&ifp->lock);
4671 			/* We try to batch several events at once. */
4672 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4673 
4674 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4675 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4676 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4677 			    !ifp->regen_count && ifp->ifpub) {
4678 				/* This is a non-regenerated temporary addr. */
4679 
4680 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4681 
4682 				if (age + regen_advance >= ifp->prefered_lft) {
4683 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4684 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4685 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4686 
4687 					ifp->regen_count++;
4688 					in6_ifa_hold(ifp);
4689 					in6_ifa_hold(ifpub);
4690 					spin_unlock(&ifp->lock);
4691 
4692 					spin_lock(&ifpub->lock);
4693 					ifpub->regen_count = 0;
4694 					spin_unlock(&ifpub->lock);
4695 					rcu_read_unlock_bh();
4696 					ipv6_create_tempaddr(ifpub, true);
4697 					in6_ifa_put(ifpub);
4698 					in6_ifa_put(ifp);
4699 					rcu_read_lock_bh();
4700 					goto restart;
4701 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4702 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4703 			}
4704 
4705 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4706 			    age >= ifp->valid_lft) {
4707 				spin_unlock(&ifp->lock);
4708 				in6_ifa_hold(ifp);
4709 				rcu_read_unlock_bh();
4710 				ipv6_del_addr(ifp);
4711 				rcu_read_lock_bh();
4712 				goto restart;
4713 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4714 				spin_unlock(&ifp->lock);
4715 				continue;
4716 			} else if (age >= ifp->prefered_lft) {
4717 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4718 				int deprecate = 0;
4719 
4720 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4721 					deprecate = 1;
4722 					ifp->flags |= IFA_F_DEPRECATED;
4723 				}
4724 
4725 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4726 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4727 					next = ifp->tstamp + ifp->valid_lft * HZ;
4728 
4729 				spin_unlock(&ifp->lock);
4730 
4731 				if (deprecate) {
4732 					in6_ifa_hold(ifp);
4733 
4734 					ipv6_ifa_notify(0, ifp);
4735 					in6_ifa_put(ifp);
4736 					goto restart;
4737 				}
4738 			} else {
4739 				/* ifp->prefered_lft <= ifp->valid_lft */
4740 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4741 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4742 				spin_unlock(&ifp->lock);
4743 			}
4744 		}
4745 	}
4746 
4747 	next_sec = round_jiffies_up(next);
4748 	next_sched = next;
4749 
4750 	/* If rounded timeout is accurate enough, accept it. */
4751 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4752 		next_sched = next_sec;
4753 
4754 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4755 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4756 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4757 
4758 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4759 		 now, next, next_sec, next_sched);
4760 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4761 	rcu_read_unlock_bh();
4762 }
4763 
4764 static void addrconf_verify_work(struct work_struct *w)
4765 {
4766 	struct net *net = container_of(to_delayed_work(w), struct net,
4767 				       ipv6.addr_chk_work);
4768 
4769 	rtnl_net_lock(net);
4770 	addrconf_verify_rtnl(net);
4771 	rtnl_net_unlock(net);
4772 }
4773 
4774 static void addrconf_verify(struct net *net)
4775 {
4776 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4777 }
4778 
4779 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4780 				     struct in6_addr **peer_pfx)
4781 {
4782 	struct in6_addr *pfx = NULL;
4783 
4784 	*peer_pfx = NULL;
4785 
4786 	if (addr)
4787 		pfx = nla_data(addr);
4788 
4789 	if (local) {
4790 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4791 			*peer_pfx = pfx;
4792 		pfx = nla_data(local);
4793 	}
4794 
4795 	return pfx;
4796 }
4797 
4798 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4799 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4800 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4801 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4802 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4803 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4804 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4805 	[IFA_PROTO]		= { .type = NLA_U8 },
4806 };
4807 
4808 static int
4809 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4810 		  struct netlink_ext_ack *extack)
4811 {
4812 	struct net *net = sock_net(skb->sk);
4813 	struct ifaddrmsg *ifm;
4814 	struct nlattr *tb[IFA_MAX+1];
4815 	struct in6_addr *pfx, *peer_pfx;
4816 	u32 ifa_flags;
4817 	int err;
4818 
4819 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4820 				     ifa_ipv6_policy, extack);
4821 	if (err < 0)
4822 		return err;
4823 
4824 	ifm = nlmsg_data(nlh);
4825 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4826 	if (!pfx)
4827 		return -EINVAL;
4828 
4829 	ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4830 
4831 	/* We ignore other flags so far. */
4832 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4833 
4834 	rtnl_net_lock(net);
4835 	err = inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4836 			     ifm->ifa_prefixlen, extack);
4837 	rtnl_net_unlock(net);
4838 
4839 	return err;
4840 }
4841 
4842 static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp,
4843 			       unsigned long expires, u32 flags,
4844 			       bool modify_peer)
4845 {
4846 	struct fib6_table *table;
4847 	struct fib6_info *f6i;
4848 	u32 prio;
4849 
4850 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4851 					ifp->prefix_len,
4852 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4853 	if (!f6i)
4854 		return -ENOENT;
4855 
4856 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4857 	if (f6i->fib6_metric != prio) {
4858 		/* delete old one */
4859 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4860 
4861 		/* add new one */
4862 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4863 				      ifp->prefix_len,
4864 				      ifp->rt_priority, ifp->idev->dev,
4865 				      expires, flags, GFP_KERNEL);
4866 		return 0;
4867 	}
4868 	if (f6i != net->ipv6.fib6_null_entry) {
4869 		table = f6i->fib6_table;
4870 		spin_lock_bh(&table->tb6_lock);
4871 
4872 		if (!(flags & RTF_EXPIRES)) {
4873 			fib6_clean_expires(f6i);
4874 			fib6_may_remove_gc_list(net, f6i);
4875 		} else {
4876 			fib6_set_expires(f6i, expires);
4877 			fib6_add_gc_list(f6i);
4878 		}
4879 
4880 		spin_unlock_bh(&table->tb6_lock);
4881 	}
4882 	fib6_info_release(f6i);
4883 
4884 	return 0;
4885 }
4886 
4887 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4888 			     struct ifa6_config *cfg, clock_t expires,
4889 			     u32 flags)
4890 {
4891 	bool was_managetempaddr;
4892 	bool new_peer = false;
4893 	bool had_prefixroute;
4894 
4895 	ASSERT_RTNL_NET(net);
4896 
4897 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4898 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4899 		return -EINVAL;
4900 
4901 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4902 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4903 
4904 	if (cfg->peer_pfx &&
4905 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4906 		if (!ipv6_addr_any(&ifp->peer_addr))
4907 			cleanup_prefix_route(ifp, expires, true, true);
4908 		new_peer = true;
4909 	}
4910 
4911 	spin_lock_bh(&ifp->lock);
4912 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4913 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4914 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4915 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4916 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4917 			IFA_F_NOPREFIXROUTE);
4918 	ifp->flags |= cfg->ifa_flags;
4919 	WRITE_ONCE(ifp->tstamp, jiffies);
4920 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4921 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4922 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4923 
4924 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4925 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4926 
4927 	if (new_peer)
4928 		ifp->peer_addr = *cfg->peer_pfx;
4929 
4930 	spin_unlock_bh(&ifp->lock);
4931 	if (!(ifp->flags&IFA_F_TENTATIVE))
4932 		ipv6_ifa_notify(0, ifp);
4933 
4934 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4935 		int rc = -ENOENT;
4936 
4937 		if (had_prefixroute)
4938 			rc = modify_prefix_route(net, ifp, expires, flags, false);
4939 
4940 		/* prefix route could have been deleted; if so restore it */
4941 		if (rc == -ENOENT) {
4942 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4943 					      ifp->rt_priority, ifp->idev->dev,
4944 					      expires, flags, GFP_KERNEL);
4945 		}
4946 
4947 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4948 			rc = modify_prefix_route(net, ifp, expires, flags, true);
4949 
4950 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4951 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4952 					      ifp->rt_priority, ifp->idev->dev,
4953 					      expires, flags, GFP_KERNEL);
4954 		}
4955 	} else if (had_prefixroute) {
4956 		enum cleanup_prefix_rt_t action;
4957 		unsigned long rt_expires;
4958 
4959 		write_lock_bh(&ifp->idev->lock);
4960 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4961 		write_unlock_bh(&ifp->idev->lock);
4962 
4963 		if (action != CLEANUP_PREFIX_RT_NOP) {
4964 			cleanup_prefix_route(ifp, rt_expires,
4965 				action == CLEANUP_PREFIX_RT_DEL, false);
4966 		}
4967 	}
4968 
4969 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4970 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4971 			delete_tempaddrs(ifp->idev, ifp);
4972 		else
4973 			manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4974 					 cfg->preferred_lft, !was_managetempaddr,
4975 					 jiffies);
4976 	}
4977 
4978 	addrconf_verify_rtnl(net);
4979 
4980 	return 0;
4981 }
4982 
4983 static int
4984 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4985 		  struct netlink_ext_ack *extack)
4986 {
4987 	struct net *net = sock_net(skb->sk);
4988 	struct nlattr *tb[IFA_MAX+1];
4989 	struct in6_addr *peer_pfx;
4990 	struct inet6_ifaddr *ifa;
4991 	struct net_device *dev;
4992 	struct inet6_dev *idev;
4993 	struct ifa6_config cfg;
4994 	struct ifaddrmsg *ifm;
4995 	unsigned long timeout;
4996 	clock_t expires;
4997 	u32 flags;
4998 	int err;
4999 
5000 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5001 				     ifa_ipv6_policy, extack);
5002 	if (err < 0)
5003 		return err;
5004 
5005 	memset(&cfg, 0, sizeof(cfg));
5006 
5007 	ifm = nlmsg_data(nlh);
5008 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
5009 	if (!cfg.pfx)
5010 		return -EINVAL;
5011 
5012 	cfg.peer_pfx = peer_pfx;
5013 	cfg.plen = ifm->ifa_prefixlen;
5014 	if (tb[IFA_RT_PRIORITY])
5015 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
5016 
5017 	if (tb[IFA_PROTO])
5018 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
5019 
5020 	cfg.ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
5021 
5022 	/* We ignore other flags so far. */
5023 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
5024 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
5025 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
5026 
5027 	cfg.ifa_flags |= IFA_F_PERMANENT;
5028 	cfg.valid_lft = INFINITY_LIFE_TIME;
5029 	cfg.preferred_lft = INFINITY_LIFE_TIME;
5030 	expires = 0;
5031 	flags = 0;
5032 
5033 	if (tb[IFA_CACHEINFO]) {
5034 		struct ifa_cacheinfo *ci;
5035 
5036 		ci = nla_data(tb[IFA_CACHEINFO]);
5037 		cfg.valid_lft = ci->ifa_valid;
5038 		cfg.preferred_lft = ci->ifa_prefered;
5039 
5040 		if (!cfg.valid_lft || cfg.preferred_lft > cfg.valid_lft) {
5041 			NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
5042 			return -EINVAL;
5043 		}
5044 
5045 		timeout = addrconf_timeout_fixup(cfg.valid_lft, HZ);
5046 		if (addrconf_finite_timeout(timeout)) {
5047 			cfg.ifa_flags &= ~IFA_F_PERMANENT;
5048 			cfg.valid_lft = timeout;
5049 			expires = jiffies_to_clock_t(timeout * HZ);
5050 			flags = RTF_EXPIRES;
5051 		}
5052 
5053 		timeout = addrconf_timeout_fixup(cfg.preferred_lft, HZ);
5054 		if (addrconf_finite_timeout(timeout)) {
5055 			if (timeout == 0)
5056 				cfg.ifa_flags |= IFA_F_DEPRECATED;
5057 
5058 			cfg.preferred_lft = timeout;
5059 		}
5060 	}
5061 
5062 	rtnl_net_lock(net);
5063 
5064 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5065 	if (!dev) {
5066 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5067 		err = -ENODEV;
5068 		goto unlock_rtnl;
5069 	}
5070 
5071 	netdev_lock_ops(dev);
5072 	idev = ipv6_find_idev(dev);
5073 	if (IS_ERR(idev)) {
5074 		err = PTR_ERR(idev);
5075 		goto unlock;
5076 	}
5077 
5078 	if (!ipv6_allow_optimistic_dad(net, idev))
5079 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5080 
5081 	if (cfg.ifa_flags & IFA_F_NODAD &&
5082 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5083 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5084 		err = -EINVAL;
5085 		goto unlock;
5086 	}
5087 
5088 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5089 	if (!ifa) {
5090 		/*
5091 		 * It would be best to check for !NLM_F_CREATE here but
5092 		 * userspace already relies on not having to provide this.
5093 		 */
5094 		err = inet6_addr_add(net, dev, &cfg, expires, flags, extack);
5095 		goto unlock;
5096 	}
5097 
5098 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5099 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5100 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5101 		err = -EEXIST;
5102 	} else {
5103 		err = inet6_addr_modify(net, ifa, &cfg, expires, flags);
5104 	}
5105 
5106 	in6_ifa_put(ifa);
5107 unlock:
5108 	netdev_unlock_ops(dev);
5109 unlock_rtnl:
5110 	rtnl_net_unlock(net);
5111 
5112 	return err;
5113 }
5114 
5115 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5116 			  u8 scope, int ifindex)
5117 {
5118 	struct ifaddrmsg *ifm;
5119 
5120 	ifm = nlmsg_data(nlh);
5121 	ifm->ifa_family = AF_INET6;
5122 	ifm->ifa_prefixlen = prefixlen;
5123 	ifm->ifa_flags = flags;
5124 	ifm->ifa_scope = scope;
5125 	ifm->ifa_index = ifindex;
5126 }
5127 
5128 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5129 			 unsigned long tstamp, u32 preferred, u32 valid)
5130 {
5131 	struct ifa_cacheinfo ci;
5132 
5133 	ci.cstamp = cstamp_delta(cstamp);
5134 	ci.tstamp = cstamp_delta(tstamp);
5135 	ci.ifa_prefered = preferred;
5136 	ci.ifa_valid = valid;
5137 
5138 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5139 }
5140 
5141 static inline int rt_scope(int ifa_scope)
5142 {
5143 	if (ifa_scope & IFA_HOST)
5144 		return RT_SCOPE_HOST;
5145 	else if (ifa_scope & IFA_LINK)
5146 		return RT_SCOPE_LINK;
5147 	else if (ifa_scope & IFA_SITE)
5148 		return RT_SCOPE_SITE;
5149 	else
5150 		return RT_SCOPE_UNIVERSE;
5151 }
5152 
5153 static inline int inet6_ifaddr_msgsize(void)
5154 {
5155 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5156 	       + nla_total_size(16) /* IFA_LOCAL */
5157 	       + nla_total_size(16) /* IFA_ADDRESS */
5158 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5159 	       + nla_total_size(4)  /* IFA_FLAGS */
5160 	       + nla_total_size(1)  /* IFA_PROTO */
5161 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5162 }
5163 
5164 static int inet6_fill_ifaddr(struct sk_buff *skb,
5165 			     const struct inet6_ifaddr *ifa,
5166 			     struct inet6_fill_args *args)
5167 {
5168 	struct nlmsghdr *nlh;
5169 	u32 preferred, valid;
5170 	u32 flags, priority;
5171 	u8 proto;
5172 
5173 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5174 			sizeof(struct ifaddrmsg), args->flags);
5175 	if (!nlh)
5176 		return -EMSGSIZE;
5177 
5178 	flags = READ_ONCE(ifa->flags);
5179 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5180 		      ifa->idev->dev->ifindex);
5181 
5182 	if (args->netnsid >= 0 &&
5183 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5184 		goto error;
5185 
5186 	preferred = READ_ONCE(ifa->prefered_lft);
5187 	valid = READ_ONCE(ifa->valid_lft);
5188 
5189 	if (!((flags & IFA_F_PERMANENT) &&
5190 	      (preferred == INFINITY_LIFE_TIME))) {
5191 		if (preferred != INFINITY_LIFE_TIME) {
5192 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5193 
5194 			if (preferred > tval)
5195 				preferred -= tval;
5196 			else
5197 				preferred = 0;
5198 			if (valid != INFINITY_LIFE_TIME) {
5199 				if (valid > tval)
5200 					valid -= tval;
5201 				else
5202 					valid = 0;
5203 			}
5204 		}
5205 	} else {
5206 		preferred = INFINITY_LIFE_TIME;
5207 		valid = INFINITY_LIFE_TIME;
5208 	}
5209 
5210 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5211 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5212 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5213 			goto error;
5214 	} else {
5215 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5216 			goto error;
5217 	}
5218 
5219 	priority = READ_ONCE(ifa->rt_priority);
5220 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5221 		goto error;
5222 
5223 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5224 			  preferred, valid) < 0)
5225 		goto error;
5226 
5227 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5228 		goto error;
5229 
5230 	proto = READ_ONCE(ifa->ifa_proto);
5231 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5232 		goto error;
5233 
5234 	nlmsg_end(skb, nlh);
5235 	return 0;
5236 
5237 error:
5238 	nlmsg_cancel(skb, nlh);
5239 	return -EMSGSIZE;
5240 }
5241 
5242 int inet6_fill_ifmcaddr(struct sk_buff *skb,
5243 			const struct ifmcaddr6 *ifmca,
5244 			struct inet6_fill_args *args)
5245 {
5246 	int ifindex = ifmca->idev->dev->ifindex;
5247 	u8 scope = RT_SCOPE_UNIVERSE;
5248 	struct nlmsghdr *nlh;
5249 
5250 	if (!args->force_rt_scope_universe &&
5251 	    ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5252 		scope = RT_SCOPE_SITE;
5253 
5254 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5255 			sizeof(struct ifaddrmsg), args->flags);
5256 	if (!nlh)
5257 		return -EMSGSIZE;
5258 
5259 	if (args->netnsid >= 0 &&
5260 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5261 		nlmsg_cancel(skb, nlh);
5262 		return -EMSGSIZE;
5263 	}
5264 
5265 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5266 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5267 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5268 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5269 		nlmsg_cancel(skb, nlh);
5270 		return -EMSGSIZE;
5271 	}
5272 
5273 	nlmsg_end(skb, nlh);
5274 	return 0;
5275 }
5276 
5277 int inet6_fill_ifacaddr(struct sk_buff *skb,
5278 			const struct ifacaddr6 *ifaca,
5279 			struct inet6_fill_args *args)
5280 {
5281 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5282 	int ifindex = dev ? dev->ifindex : 1;
5283 	u8 scope = RT_SCOPE_UNIVERSE;
5284 	struct nlmsghdr *nlh;
5285 
5286 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5287 		scope = RT_SCOPE_SITE;
5288 
5289 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5290 			sizeof(struct ifaddrmsg), args->flags);
5291 	if (!nlh)
5292 		return -EMSGSIZE;
5293 
5294 	if (args->netnsid >= 0 &&
5295 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5296 		nlmsg_cancel(skb, nlh);
5297 		return -EMSGSIZE;
5298 	}
5299 
5300 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5301 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5302 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5303 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5304 		nlmsg_cancel(skb, nlh);
5305 		return -EMSGSIZE;
5306 	}
5307 
5308 	nlmsg_end(skb, nlh);
5309 	return 0;
5310 }
5311 
5312 /* called with rcu_read_lock() */
5313 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5314 			  struct netlink_callback *cb, int *s_ip_idx,
5315 			  struct inet6_fill_args *fillargs)
5316 {
5317 	const struct ifmcaddr6 *ifmca;
5318 	const struct ifacaddr6 *ifaca;
5319 	int ip_idx = 0;
5320 	int err = 0;
5321 
5322 	switch (fillargs->type) {
5323 	case UNICAST_ADDR: {
5324 		const struct inet6_ifaddr *ifa;
5325 		fillargs->event = RTM_NEWADDR;
5326 
5327 		/* unicast address incl. temp addr */
5328 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5329 			if (ip_idx < *s_ip_idx)
5330 				goto next;
5331 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5332 			if (err < 0)
5333 				break;
5334 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5335 next:
5336 			ip_idx++;
5337 		}
5338 		break;
5339 	}
5340 	case MULTICAST_ADDR:
5341 		fillargs->event = RTM_GETMULTICAST;
5342 
5343 		/* multicast address */
5344 		for (ifmca = rcu_dereference(idev->mc_list);
5345 		     ifmca;
5346 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5347 			if (ip_idx < *s_ip_idx)
5348 				continue;
5349 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5350 			if (err < 0)
5351 				break;
5352 		}
5353 		break;
5354 	case ANYCAST_ADDR:
5355 		fillargs->event = RTM_GETANYCAST;
5356 		/* anycast address */
5357 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5358 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5359 			if (ip_idx < *s_ip_idx)
5360 				continue;
5361 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5362 			if (err < 0)
5363 				break;
5364 		}
5365 		break;
5366 	default:
5367 		break;
5368 	}
5369 	*s_ip_idx = err ? ip_idx : 0;
5370 	return err;
5371 }
5372 
5373 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5374 				       struct inet6_fill_args *fillargs,
5375 				       struct net **tgt_net, struct sock *sk,
5376 				       struct netlink_callback *cb)
5377 {
5378 	struct netlink_ext_ack *extack = cb->extack;
5379 	struct nlattr *tb[IFA_MAX+1];
5380 	struct ifaddrmsg *ifm;
5381 	int err, i;
5382 
5383 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5384 	if (!ifm) {
5385 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5386 		return -EINVAL;
5387 	}
5388 
5389 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5390 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5391 		return -EINVAL;
5392 	}
5393 
5394 	fillargs->ifindex = ifm->ifa_index;
5395 	if (fillargs->ifindex) {
5396 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5397 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5398 	}
5399 
5400 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5401 					    ifa_ipv6_policy, extack);
5402 	if (err < 0)
5403 		return err;
5404 
5405 	for (i = 0; i <= IFA_MAX; ++i) {
5406 		if (!tb[i])
5407 			continue;
5408 
5409 		if (i == IFA_TARGET_NETNSID) {
5410 			struct net *net;
5411 
5412 			fillargs->netnsid = nla_get_s32(tb[i]);
5413 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5414 			if (IS_ERR(net)) {
5415 				fillargs->netnsid = -1;
5416 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5417 				return PTR_ERR(net);
5418 			}
5419 			*tgt_net = net;
5420 		} else {
5421 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5422 			return -EINVAL;
5423 		}
5424 	}
5425 
5426 	return 0;
5427 }
5428 
5429 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5430 			   enum addr_type_t type)
5431 {
5432 	struct net *tgt_net = sock_net(skb->sk);
5433 	const struct nlmsghdr *nlh = cb->nlh;
5434 	struct inet6_fill_args fillargs = {
5435 		.portid = NETLINK_CB(cb->skb).portid,
5436 		.seq = cb->nlh->nlmsg_seq,
5437 		.flags = NLM_F_MULTI,
5438 		.netnsid = -1,
5439 		.type = type,
5440 		.force_rt_scope_universe = false,
5441 	};
5442 	struct {
5443 		unsigned long ifindex;
5444 		int ip_idx;
5445 	} *ctx = (void *)cb->ctx;
5446 	struct net_device *dev;
5447 	struct inet6_dev *idev;
5448 	int err = 0;
5449 
5450 	rcu_read_lock();
5451 	if (cb->strict_check) {
5452 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5453 						  skb->sk, cb);
5454 		if (err < 0)
5455 			goto done;
5456 
5457 		err = 0;
5458 		if (fillargs.ifindex) {
5459 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5460 			if (!dev) {
5461 				err = -ENODEV;
5462 				goto done;
5463 			}
5464 			idev = __in6_dev_get(dev);
5465 			if (idev)
5466 				err = in6_dump_addrs(idev, skb, cb,
5467 						     &ctx->ip_idx,
5468 						     &fillargs);
5469 			goto done;
5470 		}
5471 	}
5472 
5473 	cb->seq = inet6_base_seq(tgt_net);
5474 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5475 		idev = __in6_dev_get(dev);
5476 		if (!idev)
5477 			continue;
5478 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5479 				     &fillargs);
5480 		if (err < 0)
5481 			goto done;
5482 	}
5483 done:
5484 	rcu_read_unlock();
5485 	if (fillargs.netnsid >= 0)
5486 		put_net(tgt_net);
5487 
5488 	return err;
5489 }
5490 
5491 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5492 {
5493 	enum addr_type_t type = UNICAST_ADDR;
5494 
5495 	return inet6_dump_addr(skb, cb, type);
5496 }
5497 
5498 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5499 {
5500 	enum addr_type_t type = MULTICAST_ADDR;
5501 
5502 	return inet6_dump_addr(skb, cb, type);
5503 }
5504 
5505 
5506 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5507 {
5508 	enum addr_type_t type = ANYCAST_ADDR;
5509 
5510 	return inet6_dump_addr(skb, cb, type);
5511 }
5512 
5513 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5514 				       const struct nlmsghdr *nlh,
5515 				       struct nlattr **tb,
5516 				       struct netlink_ext_ack *extack)
5517 {
5518 	struct ifaddrmsg *ifm;
5519 	int i, err;
5520 
5521 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5522 	if (!ifm) {
5523 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5524 		return -EINVAL;
5525 	}
5526 
5527 	if (!netlink_strict_get_check(skb))
5528 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5529 					      ifa_ipv6_policy, extack);
5530 
5531 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5532 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5533 		return -EINVAL;
5534 	}
5535 
5536 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5537 					    ifa_ipv6_policy, extack);
5538 	if (err)
5539 		return err;
5540 
5541 	for (i = 0; i <= IFA_MAX; i++) {
5542 		if (!tb[i])
5543 			continue;
5544 
5545 		switch (i) {
5546 		case IFA_TARGET_NETNSID:
5547 		case IFA_ADDRESS:
5548 		case IFA_LOCAL:
5549 			break;
5550 		default:
5551 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5552 			return -EINVAL;
5553 		}
5554 	}
5555 
5556 	return 0;
5557 }
5558 
5559 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5560 			     struct netlink_ext_ack *extack)
5561 {
5562 	struct net *tgt_net = sock_net(in_skb->sk);
5563 	struct inet6_fill_args fillargs = {
5564 		.portid = NETLINK_CB(in_skb).portid,
5565 		.seq = nlh->nlmsg_seq,
5566 		.event = RTM_NEWADDR,
5567 		.flags = 0,
5568 		.netnsid = -1,
5569 		.force_rt_scope_universe = false,
5570 	};
5571 	struct ifaddrmsg *ifm;
5572 	struct nlattr *tb[IFA_MAX+1];
5573 	struct in6_addr *addr = NULL, *peer;
5574 	struct net_device *dev = NULL;
5575 	struct inet6_ifaddr *ifa;
5576 	struct sk_buff *skb;
5577 	int err;
5578 
5579 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5580 	if (err < 0)
5581 		return err;
5582 
5583 	if (tb[IFA_TARGET_NETNSID]) {
5584 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5585 
5586 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5587 						  fillargs.netnsid);
5588 		if (IS_ERR(tgt_net))
5589 			return PTR_ERR(tgt_net);
5590 	}
5591 
5592 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5593 	if (!addr) {
5594 		err = -EINVAL;
5595 		goto errout;
5596 	}
5597 	ifm = nlmsg_data(nlh);
5598 	if (ifm->ifa_index)
5599 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5600 
5601 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5602 	if (!ifa) {
5603 		err = -EADDRNOTAVAIL;
5604 		goto errout;
5605 	}
5606 
5607 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5608 	if (!skb) {
5609 		err = -ENOBUFS;
5610 		goto errout_ifa;
5611 	}
5612 
5613 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5614 	if (err < 0) {
5615 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5616 		WARN_ON(err == -EMSGSIZE);
5617 		kfree_skb(skb);
5618 		goto errout_ifa;
5619 	}
5620 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5621 errout_ifa:
5622 	in6_ifa_put(ifa);
5623 errout:
5624 	dev_put(dev);
5625 	if (fillargs.netnsid >= 0)
5626 		put_net(tgt_net);
5627 
5628 	return err;
5629 }
5630 
5631 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5632 {
5633 	struct sk_buff *skb;
5634 	struct net *net = dev_net(ifa->idev->dev);
5635 	struct inet6_fill_args fillargs = {
5636 		.portid = 0,
5637 		.seq = 0,
5638 		.event = event,
5639 		.flags = 0,
5640 		.netnsid = -1,
5641 		.force_rt_scope_universe = false,
5642 	};
5643 	int err = -ENOBUFS;
5644 
5645 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5646 	if (!skb)
5647 		goto errout;
5648 
5649 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5650 	if (err < 0) {
5651 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5652 		WARN_ON(err == -EMSGSIZE);
5653 		kfree_skb(skb);
5654 		goto errout;
5655 	}
5656 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5657 	return;
5658 errout:
5659 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5660 }
5661 
5662 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5663 			       __s32 *array, int bytes)
5664 {
5665 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5666 
5667 	memset(array, 0, bytes);
5668 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5669 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5670 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5671 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5672 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5673 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5674 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5675 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5676 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5677 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5678 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5679 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5680 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5681 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5682 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5683 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5684 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5685 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5686 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5687 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5688 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5689 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5690 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5691 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5692 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5693 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5694 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5695 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5696 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5697 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5698 #ifdef CONFIG_IPV6_ROUTER_PREF
5699 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5700 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5701 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5702 #ifdef CONFIG_IPV6_ROUTE_INFO
5703 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5704 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5705 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5706 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5707 #endif
5708 #endif
5709 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5710 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5711 		READ_ONCE(cnf->accept_source_route);
5712 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5713 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5714 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5715 #endif
5716 #ifdef CONFIG_IPV6_MROUTE
5717 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5718 #endif
5719 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5720 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5721 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5722 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5723 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5724 		READ_ONCE(cnf->suppress_frag_ndisc);
5725 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5726 		READ_ONCE(cnf->accept_ra_from_local);
5727 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5728 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5729 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5730 	/* we omit DEVCONF_STABLE_SECRET for now */
5731 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5732 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5733 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5734 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5735 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5736 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5737 #ifdef CONFIG_IPV6_SEG6_HMAC
5738 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5739 #endif
5740 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5741 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5742 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5743 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5744 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5745 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5746 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5747 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5748 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5749 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5750 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5751 		READ_ONCE(cnf->accept_untracked_na);
5752 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5753 	array[DEVCONF_FORCE_FORWARDING] = READ_ONCE(cnf->force_forwarding);
5754 }
5755 
5756 static inline size_t inet6_ifla6_size(void)
5757 {
5758 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5759 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5760 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5761 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5762 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5763 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5764 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5765 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5766 	     + 0;
5767 }
5768 
5769 static inline size_t inet6_if_nlmsg_size(void)
5770 {
5771 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5772 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5773 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5774 	       + nla_total_size(4) /* IFLA_MTU */
5775 	       + nla_total_size(4) /* IFLA_LINK */
5776 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5777 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5778 }
5779 
5780 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5781 					int bytes)
5782 {
5783 	int i;
5784 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5785 	BUG_ON(pad < 0);
5786 
5787 	/* Use put_unaligned() because stats may not be aligned for u64. */
5788 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5789 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5790 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5791 
5792 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5793 }
5794 
5795 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5796 					int bytes, size_t syncpoff)
5797 {
5798 	int i, c;
5799 	u64 buff[IPSTATS_MIB_MAX];
5800 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5801 
5802 	BUG_ON(pad < 0);
5803 
5804 	memset(buff, 0, sizeof(buff));
5805 	buff[0] = IPSTATS_MIB_MAX;
5806 
5807 	for_each_possible_cpu(c) {
5808 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5809 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5810 	}
5811 
5812 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5813 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5814 }
5815 
5816 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5817 			     int bytes)
5818 {
5819 	switch (attrtype) {
5820 	case IFLA_INET6_STATS:
5821 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5822 				     offsetof(struct ipstats_mib, syncp));
5823 		break;
5824 	case IFLA_INET6_ICMP6STATS:
5825 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5826 		break;
5827 	}
5828 }
5829 
5830 static int inet6_fill_ifla6_stats_attrs(struct sk_buff *skb,
5831 					struct inet6_dev *idev)
5832 {
5833 	struct nlattr *nla;
5834 
5835 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5836 	if (!nla)
5837 		goto nla_put_failure;
5838 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5839 
5840 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5841 	if (!nla)
5842 		goto nla_put_failure;
5843 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5844 
5845 	return 0;
5846 
5847 nla_put_failure:
5848 	return -EMSGSIZE;
5849 }
5850 
5851 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5852 				  u32 ext_filter_mask)
5853 {
5854 	struct ifla_cacheinfo ci;
5855 	struct nlattr *nla;
5856 	u32 ra_mtu;
5857 
5858 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5859 		goto nla_put_failure;
5860 	ci.max_reasm_len = IPV6_MAXPLEN;
5861 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5862 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5863 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5864 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5865 		goto nla_put_failure;
5866 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5867 	if (!nla)
5868 		goto nla_put_failure;
5869 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5870 
5871 	/* XXX - MC not implemented */
5872 
5873 	if (!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS)) {
5874 		if (inet6_fill_ifla6_stats_attrs(skb, idev) < 0)
5875 			goto nla_put_failure;
5876 	}
5877 
5878 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5879 	if (!nla)
5880 		goto nla_put_failure;
5881 	read_lock_bh(&idev->lock);
5882 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5883 	read_unlock_bh(&idev->lock);
5884 
5885 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5886 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5887 		goto nla_put_failure;
5888 
5889 	ra_mtu = READ_ONCE(idev->ra_mtu);
5890 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5891 		goto nla_put_failure;
5892 
5893 	return 0;
5894 
5895 nla_put_failure:
5896 	return -EMSGSIZE;
5897 }
5898 
5899 static size_t inet6_get_link_af_size(const struct net_device *dev,
5900 				     u32 ext_filter_mask)
5901 {
5902 	if (!__in6_dev_get(dev))
5903 		return 0;
5904 
5905 	return inet6_ifla6_size();
5906 }
5907 
5908 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5909 			      u32 ext_filter_mask)
5910 {
5911 	struct inet6_dev *idev = __in6_dev_get(dev);
5912 
5913 	if (!idev)
5914 		return -ENODATA;
5915 
5916 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5917 		return -EMSGSIZE;
5918 
5919 	return 0;
5920 }
5921 
5922 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5923 			     struct netlink_ext_ack *extack)
5924 {
5925 	struct inet6_ifaddr *ifp;
5926 	struct net_device *dev = idev->dev;
5927 	bool clear_token, update_rs = false;
5928 	struct in6_addr ll_addr;
5929 
5930 	ASSERT_RTNL();
5931 
5932 	if (!token)
5933 		return -EINVAL;
5934 
5935 	if (dev->flags & IFF_LOOPBACK) {
5936 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5937 		return -EINVAL;
5938 	}
5939 
5940 	if (dev->flags & IFF_NOARP) {
5941 		NL_SET_ERR_MSG_MOD(extack,
5942 				   "Device does not do neighbour discovery");
5943 		return -EINVAL;
5944 	}
5945 
5946 	if (!ipv6_accept_ra(idev)) {
5947 		NL_SET_ERR_MSG_MOD(extack,
5948 				   "Router advertisement is disabled on device");
5949 		return -EINVAL;
5950 	}
5951 
5952 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5953 		NL_SET_ERR_MSG(extack,
5954 			       "Router solicitation is disabled on device");
5955 		return -EINVAL;
5956 	}
5957 
5958 	write_lock_bh(&idev->lock);
5959 
5960 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5961 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5962 
5963 	write_unlock_bh(&idev->lock);
5964 
5965 	clear_token = ipv6_addr_any(token);
5966 	if (clear_token)
5967 		goto update_lft;
5968 
5969 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5970 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5971 			     IFA_F_OPTIMISTIC)) {
5972 		/* If we're not ready, then normal ifup will take care
5973 		 * of this. Otherwise, we need to request our rs here.
5974 		 */
5975 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5976 		update_rs = true;
5977 	}
5978 
5979 update_lft:
5980 	write_lock_bh(&idev->lock);
5981 
5982 	if (update_rs) {
5983 		idev->if_flags |= IF_RS_SENT;
5984 		idev->rs_interval = rfc3315_s14_backoff_init(
5985 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5986 		idev->rs_probes = 1;
5987 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5988 	}
5989 
5990 	/* Well, that's kinda nasty ... */
5991 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5992 		spin_lock(&ifp->lock);
5993 		if (ifp->tokenized) {
5994 			ifp->valid_lft = 0;
5995 			ifp->prefered_lft = 0;
5996 		}
5997 		spin_unlock(&ifp->lock);
5998 	}
5999 
6000 	write_unlock_bh(&idev->lock);
6001 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
6002 	addrconf_verify_rtnl(dev_net(dev));
6003 	return 0;
6004 }
6005 
6006 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
6007 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
6008 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
6009 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
6010 					    .reject_message =
6011 						"IFLA_INET6_RA_MTU can not be set" },
6012 };
6013 
6014 static int check_addr_gen_mode(int mode)
6015 {
6016 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
6017 	    mode != IN6_ADDR_GEN_MODE_NONE &&
6018 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
6019 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
6020 		return -EINVAL;
6021 	return 1;
6022 }
6023 
6024 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
6025 				int mode)
6026 {
6027 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
6028 	    !idev->cnf.stable_secret.initialized &&
6029 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
6030 		return -EINVAL;
6031 	return 1;
6032 }
6033 
6034 static int inet6_validate_link_af(const struct net_device *dev,
6035 				  const struct nlattr *nla,
6036 				  struct netlink_ext_ack *extack)
6037 {
6038 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6039 	struct inet6_dev *idev = NULL;
6040 	int err;
6041 
6042 	if (dev) {
6043 		idev = __in6_dev_get(dev);
6044 		if (!idev)
6045 			return -EAFNOSUPPORT;
6046 	}
6047 
6048 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
6049 					  inet6_af_policy, extack);
6050 	if (err)
6051 		return err;
6052 
6053 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6054 		return -EINVAL;
6055 
6056 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6057 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6058 
6059 		if (check_addr_gen_mode(mode) < 0)
6060 			return -EINVAL;
6061 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6062 			return -EINVAL;
6063 	}
6064 
6065 	return 0;
6066 }
6067 
6068 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6069 			     struct netlink_ext_ack *extack)
6070 {
6071 	struct inet6_dev *idev = __in6_dev_get(dev);
6072 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6073 	int err;
6074 
6075 	if (!idev)
6076 		return -EAFNOSUPPORT;
6077 
6078 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6079 		return -EINVAL;
6080 
6081 	if (tb[IFLA_INET6_TOKEN]) {
6082 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6083 					extack);
6084 		if (err)
6085 			return err;
6086 	}
6087 
6088 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6089 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6090 
6091 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6092 	}
6093 
6094 	return 0;
6095 }
6096 
6097 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6098 			     u32 portid, u32 seq, int event, unsigned int flags)
6099 {
6100 	struct net_device *dev = idev->dev;
6101 	struct ifinfomsg *hdr;
6102 	struct nlmsghdr *nlh;
6103 	int ifindex, iflink;
6104 	void *protoinfo;
6105 
6106 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6107 	if (!nlh)
6108 		return -EMSGSIZE;
6109 
6110 	hdr = nlmsg_data(nlh);
6111 	hdr->ifi_family = AF_INET6;
6112 	hdr->__ifi_pad = 0;
6113 	hdr->ifi_type = dev->type;
6114 	ifindex = READ_ONCE(dev->ifindex);
6115 	hdr->ifi_index = ifindex;
6116 	hdr->ifi_flags = netif_get_flags(dev);
6117 	hdr->ifi_change = 0;
6118 
6119 	iflink = dev_get_iflink(dev);
6120 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6121 	    (dev->addr_len &&
6122 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6123 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6124 	    (ifindex != iflink &&
6125 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6126 	    nla_put_u8(skb, IFLA_OPERSTATE,
6127 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6128 		goto nla_put_failure;
6129 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6130 	if (!protoinfo)
6131 		goto nla_put_failure;
6132 
6133 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6134 		goto nla_put_failure;
6135 
6136 	nla_nest_end(skb, protoinfo);
6137 	nlmsg_end(skb, nlh);
6138 	return 0;
6139 
6140 nla_put_failure:
6141 	nlmsg_cancel(skb, nlh);
6142 	return -EMSGSIZE;
6143 }
6144 
6145 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6146 				   struct netlink_ext_ack *extack)
6147 {
6148 	struct ifinfomsg *ifm;
6149 
6150 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
6151 	if (!ifm) {
6152 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6153 		return -EINVAL;
6154 	}
6155 
6156 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6157 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6158 		return -EINVAL;
6159 	}
6160 
6161 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6162 	    ifm->ifi_change || ifm->ifi_index) {
6163 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6164 		return -EINVAL;
6165 	}
6166 
6167 	return 0;
6168 }
6169 
6170 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6171 {
6172 	struct net *net = sock_net(skb->sk);
6173 	struct {
6174 		unsigned long ifindex;
6175 	} *ctx = (void *)cb->ctx;
6176 	struct net_device *dev;
6177 	struct inet6_dev *idev;
6178 	int err;
6179 
6180 	/* only requests using strict checking can pass data to
6181 	 * influence the dump
6182 	 */
6183 	if (cb->strict_check) {
6184 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6185 
6186 		if (err < 0)
6187 			return err;
6188 	}
6189 
6190 	err = 0;
6191 	rcu_read_lock();
6192 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6193 		idev = __in6_dev_get(dev);
6194 		if (!idev)
6195 			continue;
6196 		err = inet6_fill_ifinfo(skb, idev,
6197 					NETLINK_CB(cb->skb).portid,
6198 					cb->nlh->nlmsg_seq,
6199 					RTM_NEWLINK, NLM_F_MULTI);
6200 		if (err < 0)
6201 			break;
6202 	}
6203 	rcu_read_unlock();
6204 
6205 	return err;
6206 }
6207 
6208 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6209 {
6210 	struct sk_buff *skb;
6211 	struct net *net = dev_net(idev->dev);
6212 	int err = -ENOBUFS;
6213 
6214 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6215 	if (!skb)
6216 		goto errout;
6217 
6218 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6219 	if (err < 0) {
6220 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6221 		WARN_ON(err == -EMSGSIZE);
6222 		kfree_skb(skb);
6223 		goto errout;
6224 	}
6225 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6226 	return;
6227 errout:
6228 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6229 }
6230 
6231 static inline size_t inet6_prefix_nlmsg_size(void)
6232 {
6233 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6234 	       + nla_total_size(sizeof(struct in6_addr))
6235 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6236 }
6237 
6238 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6239 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6240 			     int event, unsigned int flags)
6241 {
6242 	struct prefixmsg *pmsg;
6243 	struct nlmsghdr *nlh;
6244 	struct prefix_cacheinfo	ci;
6245 
6246 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6247 	if (!nlh)
6248 		return -EMSGSIZE;
6249 
6250 	pmsg = nlmsg_data(nlh);
6251 	pmsg->prefix_family = AF_INET6;
6252 	pmsg->prefix_pad1 = 0;
6253 	pmsg->prefix_pad2 = 0;
6254 	pmsg->prefix_ifindex = idev->dev->ifindex;
6255 	pmsg->prefix_len = pinfo->prefix_len;
6256 	pmsg->prefix_type = pinfo->type;
6257 	pmsg->prefix_pad3 = 0;
6258 	pmsg->prefix_flags = pinfo->flags;
6259 
6260 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6261 		goto nla_put_failure;
6262 	ci.preferred_time = ntohl(pinfo->prefered);
6263 	ci.valid_time = ntohl(pinfo->valid);
6264 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6265 		goto nla_put_failure;
6266 	nlmsg_end(skb, nlh);
6267 	return 0;
6268 
6269 nla_put_failure:
6270 	nlmsg_cancel(skb, nlh);
6271 	return -EMSGSIZE;
6272 }
6273 
6274 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6275 			 struct prefix_info *pinfo)
6276 {
6277 	struct sk_buff *skb;
6278 	struct net *net = dev_net(idev->dev);
6279 	int err = -ENOBUFS;
6280 
6281 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6282 	if (!skb)
6283 		goto errout;
6284 
6285 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6286 	if (err < 0) {
6287 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6288 		WARN_ON(err == -EMSGSIZE);
6289 		kfree_skb(skb);
6290 		goto errout;
6291 	}
6292 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6293 	return;
6294 errout:
6295 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6296 }
6297 
6298 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6299 {
6300 	struct net *net = dev_net(ifp->idev->dev);
6301 
6302 	if (event)
6303 		ASSERT_RTNL();
6304 
6305 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6306 
6307 	switch (event) {
6308 	case RTM_NEWADDR:
6309 		/*
6310 		 * If the address was optimistic we inserted the route at the
6311 		 * start of our DAD process, so we don't need to do it again.
6312 		 * If the device was taken down in the middle of the DAD
6313 		 * cycle there is a race where we could get here without a
6314 		 * host route, so nothing to insert. That will be fixed when
6315 		 * the device is brought up.
6316 		 */
6317 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6318 			ip6_ins_rt(net, ifp->rt);
6319 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6320 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6321 				&ifp->addr, ifp->idev->dev->name);
6322 		}
6323 
6324 		if (ifp->idev->cnf.forwarding)
6325 			addrconf_join_anycast(ifp);
6326 		if (!ipv6_addr_any(&ifp->peer_addr))
6327 			addrconf_prefix_route(&ifp->peer_addr, 128,
6328 					      ifp->rt_priority, ifp->idev->dev,
6329 					      0, 0, GFP_ATOMIC);
6330 		break;
6331 	case RTM_DELADDR:
6332 		if (ifp->idev->cnf.forwarding)
6333 			addrconf_leave_anycast(ifp);
6334 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6335 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6336 			struct fib6_info *rt;
6337 
6338 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6339 						       ifp->idev->dev, 0, 0,
6340 						       false);
6341 			if (rt)
6342 				ip6_del_rt(net, rt, false);
6343 		}
6344 		if (ifp->rt) {
6345 			ip6_del_rt(net, ifp->rt, false);
6346 			ifp->rt = NULL;
6347 		}
6348 		rt_genid_bump_ipv6(net);
6349 		break;
6350 	}
6351 	atomic_inc(&net->ipv6.dev_addr_genid);
6352 }
6353 
6354 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6355 {
6356 	if (likely(ifp->idev->dead == 0))
6357 		__ipv6_ifa_notify(event, ifp);
6358 }
6359 
6360 #ifdef CONFIG_SYSCTL
6361 
6362 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6363 		void *buffer, size_t *lenp, loff_t *ppos)
6364 {
6365 	int *valp = ctl->data;
6366 	int val = *valp;
6367 	loff_t pos = *ppos;
6368 	struct ctl_table lctl;
6369 	int ret;
6370 
6371 	/*
6372 	 * ctl->data points to idev->cnf.forwarding, we should
6373 	 * not modify it until we get the rtnl lock.
6374 	 */
6375 	lctl = *ctl;
6376 	lctl.data = &val;
6377 
6378 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6379 	if (ret)
6380 		return ret;
6381 
6382 	if (write)
6383 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6384 	if (ret)
6385 		*ppos = pos;
6386 	return ret;
6387 }
6388 
6389 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6390 		void *buffer, size_t *lenp, loff_t *ppos)
6391 {
6392 	struct inet6_dev *idev = ctl->extra1;
6393 	int min_mtu = IPV6_MIN_MTU;
6394 	struct ctl_table lctl;
6395 
6396 	lctl = *ctl;
6397 	lctl.extra1 = &min_mtu;
6398 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6399 
6400 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6401 }
6402 
6403 static void dev_disable_change(struct inet6_dev *idev)
6404 {
6405 	struct netdev_notifier_info info;
6406 
6407 	if (!idev || !idev->dev)
6408 		return;
6409 
6410 	netdev_notifier_info_init(&info, idev->dev);
6411 	if (idev->cnf.disable_ipv6)
6412 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6413 	else
6414 		addrconf_notify(NULL, NETDEV_UP, &info);
6415 }
6416 
6417 static void addrconf_disable_change(struct net *net, __s32 newf)
6418 {
6419 	struct net_device *dev;
6420 	struct inet6_dev *idev;
6421 
6422 	for_each_netdev(net, dev) {
6423 		idev = __in6_dev_get_rtnl_net(dev);
6424 		if (idev) {
6425 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6426 
6427 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6428 			if (changed)
6429 				dev_disable_change(idev);
6430 		}
6431 	}
6432 }
6433 
6434 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6435 {
6436 	struct net *net = (struct net *)table->extra2;
6437 	int old;
6438 
6439 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6440 		WRITE_ONCE(*p, newf);
6441 		return 0;
6442 	}
6443 
6444 	if (!rtnl_net_trylock(net))
6445 		return restart_syscall();
6446 
6447 	old = *p;
6448 	WRITE_ONCE(*p, newf);
6449 
6450 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6451 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6452 		addrconf_disable_change(net, newf);
6453 	} else if ((!newf) ^ (!old)) {
6454 		dev_disable_change((struct inet6_dev *)table->extra1);
6455 	}
6456 
6457 	rtnl_net_unlock(net);
6458 	return 0;
6459 }
6460 
6461 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6462 		void *buffer, size_t *lenp, loff_t *ppos)
6463 {
6464 	int *valp = ctl->data;
6465 	int val = *valp;
6466 	loff_t pos = *ppos;
6467 	struct ctl_table lctl;
6468 	int ret;
6469 
6470 	/*
6471 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6472 	 * not modify it until we get the rtnl lock.
6473 	 */
6474 	lctl = *ctl;
6475 	lctl.data = &val;
6476 
6477 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6478 	if (ret)
6479 		return ret;
6480 
6481 	if (write)
6482 		ret = addrconf_disable_ipv6(ctl, valp, val);
6483 	if (ret)
6484 		*ppos = pos;
6485 	return ret;
6486 }
6487 
6488 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6489 		void *buffer, size_t *lenp, loff_t *ppos)
6490 {
6491 	struct net *net = ctl->extra2;
6492 	int *valp = ctl->data;
6493 	int old, new;
6494 	int ret;
6495 
6496 	if (write && !rtnl_net_trylock(net))
6497 		return restart_syscall();
6498 
6499 	old = *valp;
6500 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6501 	new = *valp;
6502 
6503 	if (write && old != new) {
6504 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp) {
6505 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6506 						     NETCONFA_PROXY_NEIGH,
6507 						     NETCONFA_IFINDEX_DEFAULT,
6508 						     net->ipv6.devconf_dflt);
6509 		} else if (valp == &net->ipv6.devconf_all->proxy_ndp) {
6510 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6511 						     NETCONFA_PROXY_NEIGH,
6512 						     NETCONFA_IFINDEX_ALL,
6513 						     net->ipv6.devconf_all);
6514 		} else {
6515 			struct inet6_dev *idev = ctl->extra1;
6516 
6517 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6518 						     NETCONFA_PROXY_NEIGH,
6519 						     idev->dev->ifindex,
6520 						     &idev->cnf);
6521 		}
6522 	}
6523 	if (write)
6524 		rtnl_net_unlock(net);
6525 
6526 	return ret;
6527 }
6528 
6529 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6530 					 void *buffer, size_t *lenp,
6531 					 loff_t *ppos)
6532 {
6533 	int ret = 0;
6534 	u32 new_val;
6535 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6536 	struct net *net = (struct net *)ctl->extra2;
6537 	struct ctl_table tmp = {
6538 		.data = &new_val,
6539 		.maxlen = sizeof(new_val),
6540 		.mode = ctl->mode,
6541 	};
6542 
6543 	if (!rtnl_net_trylock(net))
6544 		return restart_syscall();
6545 
6546 	new_val = *((u32 *)ctl->data);
6547 
6548 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6549 	if (ret != 0)
6550 		goto out;
6551 
6552 	if (write) {
6553 		if (check_addr_gen_mode(new_val) < 0) {
6554 			ret = -EINVAL;
6555 			goto out;
6556 		}
6557 
6558 		if (idev) {
6559 			if (check_stable_privacy(idev, net, new_val) < 0) {
6560 				ret = -EINVAL;
6561 				goto out;
6562 			}
6563 
6564 			if (idev->cnf.addr_gen_mode != new_val) {
6565 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6566 				netdev_lock_ops(idev->dev);
6567 				addrconf_init_auto_addrs(idev->dev);
6568 				netdev_unlock_ops(idev->dev);
6569 			}
6570 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6571 			struct net_device *dev;
6572 
6573 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6574 			for_each_netdev(net, dev) {
6575 				idev = __in6_dev_get_rtnl_net(dev);
6576 				if (idev &&
6577 				    idev->cnf.addr_gen_mode != new_val) {
6578 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6579 						  new_val);
6580 					netdev_lock_ops(idev->dev);
6581 					addrconf_init_auto_addrs(idev->dev);
6582 					netdev_unlock_ops(idev->dev);
6583 				}
6584 			}
6585 		}
6586 
6587 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6588 	}
6589 
6590 out:
6591 	rtnl_net_unlock(net);
6592 
6593 	return ret;
6594 }
6595 
6596 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6597 					 void *buffer, size_t *lenp,
6598 					 loff_t *ppos)
6599 {
6600 	int err;
6601 	struct in6_addr addr;
6602 	char str[IPV6_MAX_STRLEN];
6603 	struct ctl_table lctl = *ctl;
6604 	struct net *net = ctl->extra2;
6605 	struct ipv6_stable_secret *secret = ctl->data;
6606 
6607 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6608 		return -EIO;
6609 
6610 	lctl.maxlen = IPV6_MAX_STRLEN;
6611 	lctl.data = str;
6612 
6613 	if (!rtnl_net_trylock(net))
6614 		return restart_syscall();
6615 
6616 	if (!write && !secret->initialized) {
6617 		err = -EIO;
6618 		goto out;
6619 	}
6620 
6621 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6622 	if (err >= sizeof(str)) {
6623 		err = -EIO;
6624 		goto out;
6625 	}
6626 
6627 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6628 	if (err || !write)
6629 		goto out;
6630 
6631 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6632 		err = -EIO;
6633 		goto out;
6634 	}
6635 
6636 	secret->initialized = true;
6637 	secret->secret = addr;
6638 
6639 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6640 		struct net_device *dev;
6641 
6642 		for_each_netdev(net, dev) {
6643 			struct inet6_dev *idev = __in6_dev_get_rtnl_net(dev);
6644 
6645 			if (idev) {
6646 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6647 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6648 			}
6649 		}
6650 	} else {
6651 		struct inet6_dev *idev = ctl->extra1;
6652 
6653 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6654 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6655 	}
6656 
6657 out:
6658 	rtnl_net_unlock(net);
6659 
6660 	return err;
6661 }
6662 
6663 static
6664 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6665 						int write, void *buffer,
6666 						size_t *lenp,
6667 						loff_t *ppos)
6668 {
6669 	int *valp = ctl->data;
6670 	int val = *valp;
6671 	loff_t pos = *ppos;
6672 	struct ctl_table lctl;
6673 	int ret;
6674 
6675 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6676 	 * we should not modify it until we get the rtnl lock.
6677 	 */
6678 	lctl = *ctl;
6679 	lctl.data = &val;
6680 
6681 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6682 	if (ret)
6683 		return ret;
6684 
6685 	if (write)
6686 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6687 	if (ret)
6688 		*ppos = pos;
6689 	return ret;
6690 }
6691 
6692 static
6693 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6694 {
6695 	if (rt) {
6696 		if (action)
6697 			rt->dst.flags |= DST_NOPOLICY;
6698 		else
6699 			rt->dst.flags &= ~DST_NOPOLICY;
6700 	}
6701 }
6702 
6703 static
6704 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6705 {
6706 	struct inet6_ifaddr *ifa;
6707 
6708 	read_lock_bh(&idev->lock);
6709 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6710 		spin_lock(&ifa->lock);
6711 		if (ifa->rt) {
6712 			/* host routes only use builtin fib6_nh */
6713 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6714 			int cpu;
6715 
6716 			rcu_read_lock();
6717 			ifa->rt->dst_nopolicy = val ? true : false;
6718 			if (nh->rt6i_pcpu) {
6719 				for_each_possible_cpu(cpu) {
6720 					struct rt6_info **rtp;
6721 
6722 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6723 					addrconf_set_nopolicy(*rtp, val);
6724 				}
6725 			}
6726 			rcu_read_unlock();
6727 		}
6728 		spin_unlock(&ifa->lock);
6729 	}
6730 	read_unlock_bh(&idev->lock);
6731 }
6732 
6733 static
6734 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6735 {
6736 	struct net *net = (struct net *)ctl->extra2;
6737 	struct inet6_dev *idev;
6738 
6739 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6740 		WRITE_ONCE(*valp, val);
6741 		return 0;
6742 	}
6743 
6744 	if (!rtnl_net_trylock(net))
6745 		return restart_syscall();
6746 
6747 	WRITE_ONCE(*valp, val);
6748 
6749 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6750 		struct net_device *dev;
6751 
6752 		for_each_netdev(net, dev) {
6753 			idev = __in6_dev_get_rtnl_net(dev);
6754 			if (idev)
6755 				addrconf_disable_policy_idev(idev, val);
6756 		}
6757 	} else {
6758 		idev = (struct inet6_dev *)ctl->extra1;
6759 		addrconf_disable_policy_idev(idev, val);
6760 	}
6761 
6762 	rtnl_net_unlock(net);
6763 	return 0;
6764 }
6765 
6766 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6767 				   void *buffer, size_t *lenp, loff_t *ppos)
6768 {
6769 	int *valp = ctl->data;
6770 	int val = *valp;
6771 	loff_t pos = *ppos;
6772 	struct ctl_table lctl;
6773 	int ret;
6774 
6775 	lctl = *ctl;
6776 	lctl.data = &val;
6777 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6778 	if (ret)
6779 		return ret;
6780 
6781 	if (write && (*valp != val))
6782 		ret = addrconf_disable_policy(ctl, valp, val);
6783 
6784 	if (ret)
6785 		*ppos = pos;
6786 
6787 	return ret;
6788 }
6789 
6790 static void addrconf_force_forward_change(struct net *net, __s32 newf)
6791 {
6792 	struct net_device *dev;
6793 	struct inet6_dev *idev;
6794 
6795 	for_each_netdev(net, dev) {
6796 		idev = __in6_dev_get_rtnl_net(dev);
6797 		if (idev) {
6798 			int changed = (!idev->cnf.force_forwarding) ^ (!newf);
6799 
6800 			WRITE_ONCE(idev->cnf.force_forwarding, newf);
6801 			if (changed)
6802 				inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
6803 							     NETCONFA_FORCE_FORWARDING,
6804 							     dev->ifindex, &idev->cnf);
6805 		}
6806 	}
6807 }
6808 
6809 static int addrconf_sysctl_force_forwarding(const struct ctl_table *ctl, int write,
6810 					    void *buffer, size_t *lenp, loff_t *ppos)
6811 {
6812 	struct inet6_dev *idev = ctl->extra1;
6813 	struct ctl_table tmp_ctl = *ctl;
6814 	struct net *net = ctl->extra2;
6815 	int *valp = ctl->data;
6816 	int new_val = *valp;
6817 	int old_val = *valp;
6818 	loff_t pos = *ppos;
6819 	int ret;
6820 
6821 	tmp_ctl.extra1 = SYSCTL_ZERO;
6822 	tmp_ctl.extra2 = SYSCTL_ONE;
6823 	tmp_ctl.data = &new_val;
6824 
6825 	ret = proc_douintvec_minmax(&tmp_ctl, write, buffer, lenp, ppos);
6826 
6827 	if (write && old_val != new_val) {
6828 		if (!rtnl_net_trylock(net))
6829 			return restart_syscall();
6830 
6831 		WRITE_ONCE(*valp, new_val);
6832 
6833 		if (valp == &net->ipv6.devconf_dflt->force_forwarding) {
6834 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6835 						     NETCONFA_FORCE_FORWARDING,
6836 						     NETCONFA_IFINDEX_DEFAULT,
6837 						     net->ipv6.devconf_dflt);
6838 		} else if (valp == &net->ipv6.devconf_all->force_forwarding) {
6839 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6840 						     NETCONFA_FORCE_FORWARDING,
6841 						     NETCONFA_IFINDEX_ALL,
6842 						     net->ipv6.devconf_all);
6843 
6844 			addrconf_force_forward_change(net, new_val);
6845 		} else {
6846 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6847 						     NETCONFA_FORCE_FORWARDING,
6848 						     idev->dev->ifindex,
6849 						     &idev->cnf);
6850 		}
6851 		rtnl_net_unlock(net);
6852 	}
6853 
6854 	if (ret)
6855 		*ppos = pos;
6856 	return ret;
6857 }
6858 
6859 static int minus_one = -1;
6860 static const int two_five_five = 255;
6861 static u32 ioam6_if_id_max = U16_MAX;
6862 
6863 static const struct ctl_table addrconf_sysctl[] = {
6864 	{
6865 		.procname	= "forwarding",
6866 		.data		= &ipv6_devconf.forwarding,
6867 		.maxlen		= sizeof(int),
6868 		.mode		= 0644,
6869 		.proc_handler	= addrconf_sysctl_forward,
6870 	},
6871 	{
6872 		.procname	= "hop_limit",
6873 		.data		= &ipv6_devconf.hop_limit,
6874 		.maxlen		= sizeof(int),
6875 		.mode		= 0644,
6876 		.proc_handler	= proc_dointvec_minmax,
6877 		.extra1		= (void *)SYSCTL_ONE,
6878 		.extra2		= (void *)&two_five_five,
6879 	},
6880 	{
6881 		.procname	= "mtu",
6882 		.data		= &ipv6_devconf.mtu6,
6883 		.maxlen		= sizeof(int),
6884 		.mode		= 0644,
6885 		.proc_handler	= addrconf_sysctl_mtu,
6886 	},
6887 	{
6888 		.procname	= "accept_ra",
6889 		.data		= &ipv6_devconf.accept_ra,
6890 		.maxlen		= sizeof(int),
6891 		.mode		= 0644,
6892 		.proc_handler	= proc_dointvec,
6893 	},
6894 	{
6895 		.procname	= "accept_redirects",
6896 		.data		= &ipv6_devconf.accept_redirects,
6897 		.maxlen		= sizeof(int),
6898 		.mode		= 0644,
6899 		.proc_handler	= proc_dointvec,
6900 	},
6901 	{
6902 		.procname	= "autoconf",
6903 		.data		= &ipv6_devconf.autoconf,
6904 		.maxlen		= sizeof(int),
6905 		.mode		= 0644,
6906 		.proc_handler	= proc_dointvec,
6907 	},
6908 	{
6909 		.procname	= "dad_transmits",
6910 		.data		= &ipv6_devconf.dad_transmits,
6911 		.maxlen		= sizeof(int),
6912 		.mode		= 0644,
6913 		.proc_handler	= proc_dointvec,
6914 	},
6915 	{
6916 		.procname	= "router_solicitations",
6917 		.data		= &ipv6_devconf.rtr_solicits,
6918 		.maxlen		= sizeof(int),
6919 		.mode		= 0644,
6920 		.proc_handler	= proc_dointvec_minmax,
6921 		.extra1		= &minus_one,
6922 	},
6923 	{
6924 		.procname	= "router_solicitation_interval",
6925 		.data		= &ipv6_devconf.rtr_solicit_interval,
6926 		.maxlen		= sizeof(int),
6927 		.mode		= 0644,
6928 		.proc_handler	= proc_dointvec_jiffies,
6929 	},
6930 	{
6931 		.procname	= "router_solicitation_max_interval",
6932 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6933 		.maxlen		= sizeof(int),
6934 		.mode		= 0644,
6935 		.proc_handler	= proc_dointvec_jiffies,
6936 	},
6937 	{
6938 		.procname	= "router_solicitation_delay",
6939 		.data		= &ipv6_devconf.rtr_solicit_delay,
6940 		.maxlen		= sizeof(int),
6941 		.mode		= 0644,
6942 		.proc_handler	= proc_dointvec_jiffies,
6943 	},
6944 	{
6945 		.procname	= "force_mld_version",
6946 		.data		= &ipv6_devconf.force_mld_version,
6947 		.maxlen		= sizeof(int),
6948 		.mode		= 0644,
6949 		.proc_handler	= proc_dointvec,
6950 	},
6951 	{
6952 		.procname	= "mldv1_unsolicited_report_interval",
6953 		.data		=
6954 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6955 		.maxlen		= sizeof(int),
6956 		.mode		= 0644,
6957 		.proc_handler	= proc_dointvec_ms_jiffies,
6958 	},
6959 	{
6960 		.procname	= "mldv2_unsolicited_report_interval",
6961 		.data		=
6962 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6963 		.maxlen		= sizeof(int),
6964 		.mode		= 0644,
6965 		.proc_handler	= proc_dointvec_ms_jiffies,
6966 	},
6967 	{
6968 		.procname	= "use_tempaddr",
6969 		.data		= &ipv6_devconf.use_tempaddr,
6970 		.maxlen		= sizeof(int),
6971 		.mode		= 0644,
6972 		.proc_handler	= proc_dointvec,
6973 	},
6974 	{
6975 		.procname	= "temp_valid_lft",
6976 		.data		= &ipv6_devconf.temp_valid_lft,
6977 		.maxlen		= sizeof(int),
6978 		.mode		= 0644,
6979 		.proc_handler	= proc_dointvec,
6980 	},
6981 	{
6982 		.procname	= "temp_prefered_lft",
6983 		.data		= &ipv6_devconf.temp_prefered_lft,
6984 		.maxlen		= sizeof(int),
6985 		.mode		= 0644,
6986 		.proc_handler	= proc_dointvec,
6987 	},
6988 	{
6989 		.procname       = "regen_min_advance",
6990 		.data           = &ipv6_devconf.regen_min_advance,
6991 		.maxlen         = sizeof(int),
6992 		.mode           = 0644,
6993 		.proc_handler   = proc_dointvec,
6994 	},
6995 	{
6996 		.procname	= "regen_max_retry",
6997 		.data		= &ipv6_devconf.regen_max_retry,
6998 		.maxlen		= sizeof(int),
6999 		.mode		= 0644,
7000 		.proc_handler	= proc_dointvec,
7001 	},
7002 	{
7003 		.procname	= "max_desync_factor",
7004 		.data		= &ipv6_devconf.max_desync_factor,
7005 		.maxlen		= sizeof(int),
7006 		.mode		= 0644,
7007 		.proc_handler	= proc_dointvec,
7008 	},
7009 	{
7010 		.procname	= "max_addresses",
7011 		.data		= &ipv6_devconf.max_addresses,
7012 		.maxlen		= sizeof(int),
7013 		.mode		= 0644,
7014 		.proc_handler	= proc_dointvec,
7015 	},
7016 	{
7017 		.procname	= "accept_ra_defrtr",
7018 		.data		= &ipv6_devconf.accept_ra_defrtr,
7019 		.maxlen		= sizeof(int),
7020 		.mode		= 0644,
7021 		.proc_handler	= proc_dointvec,
7022 	},
7023 	{
7024 		.procname	= "ra_defrtr_metric",
7025 		.data		= &ipv6_devconf.ra_defrtr_metric,
7026 		.maxlen		= sizeof(u32),
7027 		.mode		= 0644,
7028 		.proc_handler	= proc_douintvec_minmax,
7029 		.extra1		= (void *)SYSCTL_ONE,
7030 	},
7031 	{
7032 		.procname	= "accept_ra_min_hop_limit",
7033 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
7034 		.maxlen		= sizeof(int),
7035 		.mode		= 0644,
7036 		.proc_handler	= proc_dointvec,
7037 	},
7038 	{
7039 		.procname	= "accept_ra_min_lft",
7040 		.data		= &ipv6_devconf.accept_ra_min_lft,
7041 		.maxlen		= sizeof(int),
7042 		.mode		= 0644,
7043 		.proc_handler	= proc_dointvec,
7044 	},
7045 	{
7046 		.procname	= "accept_ra_pinfo",
7047 		.data		= &ipv6_devconf.accept_ra_pinfo,
7048 		.maxlen		= sizeof(int),
7049 		.mode		= 0644,
7050 		.proc_handler	= proc_dointvec,
7051 	},
7052 	{
7053 		.procname	= "ra_honor_pio_life",
7054 		.data		= &ipv6_devconf.ra_honor_pio_life,
7055 		.maxlen		= sizeof(u8),
7056 		.mode		= 0644,
7057 		.proc_handler	= proc_dou8vec_minmax,
7058 		.extra1		= SYSCTL_ZERO,
7059 		.extra2		= SYSCTL_ONE,
7060 	},
7061 	{
7062 		.procname	= "ra_honor_pio_pflag",
7063 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
7064 		.maxlen		= sizeof(u8),
7065 		.mode		= 0644,
7066 		.proc_handler	= proc_dou8vec_minmax,
7067 		.extra1		= SYSCTL_ZERO,
7068 		.extra2		= SYSCTL_ONE,
7069 	},
7070 #ifdef CONFIG_IPV6_ROUTER_PREF
7071 	{
7072 		.procname	= "accept_ra_rtr_pref",
7073 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
7074 		.maxlen		= sizeof(int),
7075 		.mode		= 0644,
7076 		.proc_handler	= proc_dointvec,
7077 	},
7078 	{
7079 		.procname	= "router_probe_interval",
7080 		.data		= &ipv6_devconf.rtr_probe_interval,
7081 		.maxlen		= sizeof(int),
7082 		.mode		= 0644,
7083 		.proc_handler	= proc_dointvec_jiffies,
7084 	},
7085 #ifdef CONFIG_IPV6_ROUTE_INFO
7086 	{
7087 		.procname	= "accept_ra_rt_info_min_plen",
7088 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
7089 		.maxlen		= sizeof(int),
7090 		.mode		= 0644,
7091 		.proc_handler	= proc_dointvec,
7092 	},
7093 	{
7094 		.procname	= "accept_ra_rt_info_max_plen",
7095 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
7096 		.maxlen		= sizeof(int),
7097 		.mode		= 0644,
7098 		.proc_handler	= proc_dointvec,
7099 	},
7100 #endif
7101 #endif
7102 	{
7103 		.procname	= "proxy_ndp",
7104 		.data		= &ipv6_devconf.proxy_ndp,
7105 		.maxlen		= sizeof(int),
7106 		.mode		= 0644,
7107 		.proc_handler	= addrconf_sysctl_proxy_ndp,
7108 	},
7109 	{
7110 		.procname	= "accept_source_route",
7111 		.data		= &ipv6_devconf.accept_source_route,
7112 		.maxlen		= sizeof(int),
7113 		.mode		= 0644,
7114 		.proc_handler	= proc_dointvec,
7115 	},
7116 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
7117 	{
7118 		.procname	= "optimistic_dad",
7119 		.data		= &ipv6_devconf.optimistic_dad,
7120 		.maxlen		= sizeof(int),
7121 		.mode		= 0644,
7122 		.proc_handler   = proc_dointvec,
7123 	},
7124 	{
7125 		.procname	= "use_optimistic",
7126 		.data		= &ipv6_devconf.use_optimistic,
7127 		.maxlen		= sizeof(int),
7128 		.mode		= 0644,
7129 		.proc_handler	= proc_dointvec,
7130 	},
7131 #endif
7132 #ifdef CONFIG_IPV6_MROUTE
7133 	{
7134 		.procname	= "mc_forwarding",
7135 		.data		= &ipv6_devconf.mc_forwarding,
7136 		.maxlen		= sizeof(int),
7137 		.mode		= 0444,
7138 		.proc_handler	= proc_dointvec,
7139 	},
7140 #endif
7141 	{
7142 		.procname	= "disable_ipv6",
7143 		.data		= &ipv6_devconf.disable_ipv6,
7144 		.maxlen		= sizeof(int),
7145 		.mode		= 0644,
7146 		.proc_handler	= addrconf_sysctl_disable,
7147 	},
7148 	{
7149 		.procname	= "accept_dad",
7150 		.data		= &ipv6_devconf.accept_dad,
7151 		.maxlen		= sizeof(int),
7152 		.mode		= 0644,
7153 		.proc_handler	= proc_dointvec,
7154 	},
7155 	{
7156 		.procname	= "force_tllao",
7157 		.data		= &ipv6_devconf.force_tllao,
7158 		.maxlen		= sizeof(int),
7159 		.mode		= 0644,
7160 		.proc_handler	= proc_dointvec
7161 	},
7162 	{
7163 		.procname	= "ndisc_notify",
7164 		.data		= &ipv6_devconf.ndisc_notify,
7165 		.maxlen		= sizeof(int),
7166 		.mode		= 0644,
7167 		.proc_handler	= proc_dointvec
7168 	},
7169 	{
7170 		.procname	= "suppress_frag_ndisc",
7171 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7172 		.maxlen		= sizeof(int),
7173 		.mode		= 0644,
7174 		.proc_handler	= proc_dointvec
7175 	},
7176 	{
7177 		.procname	= "accept_ra_from_local",
7178 		.data		= &ipv6_devconf.accept_ra_from_local,
7179 		.maxlen		= sizeof(int),
7180 		.mode		= 0644,
7181 		.proc_handler	= proc_dointvec,
7182 	},
7183 	{
7184 		.procname	= "accept_ra_mtu",
7185 		.data		= &ipv6_devconf.accept_ra_mtu,
7186 		.maxlen		= sizeof(int),
7187 		.mode		= 0644,
7188 		.proc_handler	= proc_dointvec,
7189 	},
7190 	{
7191 		.procname	= "stable_secret",
7192 		.data		= &ipv6_devconf.stable_secret,
7193 		.maxlen		= IPV6_MAX_STRLEN,
7194 		.mode		= 0600,
7195 		.proc_handler	= addrconf_sysctl_stable_secret,
7196 	},
7197 	{
7198 		.procname	= "use_oif_addrs_only",
7199 		.data		= &ipv6_devconf.use_oif_addrs_only,
7200 		.maxlen		= sizeof(int),
7201 		.mode		= 0644,
7202 		.proc_handler	= proc_dointvec,
7203 	},
7204 	{
7205 		.procname	= "ignore_routes_with_linkdown",
7206 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7207 		.maxlen		= sizeof(int),
7208 		.mode		= 0644,
7209 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7210 	},
7211 	{
7212 		.procname	= "drop_unicast_in_l2_multicast",
7213 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7214 		.maxlen		= sizeof(int),
7215 		.mode		= 0644,
7216 		.proc_handler	= proc_dointvec,
7217 	},
7218 	{
7219 		.procname	= "drop_unsolicited_na",
7220 		.data		= &ipv6_devconf.drop_unsolicited_na,
7221 		.maxlen		= sizeof(int),
7222 		.mode		= 0644,
7223 		.proc_handler	= proc_dointvec,
7224 	},
7225 	{
7226 		.procname	= "keep_addr_on_down",
7227 		.data		= &ipv6_devconf.keep_addr_on_down,
7228 		.maxlen		= sizeof(int),
7229 		.mode		= 0644,
7230 		.proc_handler	= proc_dointvec,
7231 
7232 	},
7233 	{
7234 		.procname	= "seg6_enabled",
7235 		.data		= &ipv6_devconf.seg6_enabled,
7236 		.maxlen		= sizeof(int),
7237 		.mode		= 0644,
7238 		.proc_handler	= proc_dointvec,
7239 	},
7240 #ifdef CONFIG_IPV6_SEG6_HMAC
7241 	{
7242 		.procname	= "seg6_require_hmac",
7243 		.data		= &ipv6_devconf.seg6_require_hmac,
7244 		.maxlen		= sizeof(int),
7245 		.mode		= 0644,
7246 		.proc_handler	= proc_dointvec,
7247 	},
7248 #endif
7249 	{
7250 		.procname       = "enhanced_dad",
7251 		.data           = &ipv6_devconf.enhanced_dad,
7252 		.maxlen         = sizeof(int),
7253 		.mode           = 0644,
7254 		.proc_handler   = proc_dointvec,
7255 	},
7256 	{
7257 		.procname	= "addr_gen_mode",
7258 		.data		= &ipv6_devconf.addr_gen_mode,
7259 		.maxlen		= sizeof(int),
7260 		.mode		= 0644,
7261 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7262 	},
7263 	{
7264 		.procname       = "disable_policy",
7265 		.data           = &ipv6_devconf.disable_policy,
7266 		.maxlen         = sizeof(int),
7267 		.mode           = 0644,
7268 		.proc_handler   = addrconf_sysctl_disable_policy,
7269 	},
7270 	{
7271 		.procname	= "ndisc_tclass",
7272 		.data		= &ipv6_devconf.ndisc_tclass,
7273 		.maxlen		= sizeof(int),
7274 		.mode		= 0644,
7275 		.proc_handler	= proc_dointvec_minmax,
7276 		.extra1		= (void *)SYSCTL_ZERO,
7277 		.extra2		= (void *)&two_five_five,
7278 	},
7279 	{
7280 		.procname	= "rpl_seg_enabled",
7281 		.data		= &ipv6_devconf.rpl_seg_enabled,
7282 		.maxlen		= sizeof(int),
7283 		.mode		= 0644,
7284 		.proc_handler   = proc_dointvec_minmax,
7285 		.extra1         = SYSCTL_ZERO,
7286 		.extra2         = SYSCTL_ONE,
7287 	},
7288 	{
7289 		.procname	= "ioam6_enabled",
7290 		.data		= &ipv6_devconf.ioam6_enabled,
7291 		.maxlen		= sizeof(u8),
7292 		.mode		= 0644,
7293 		.proc_handler	= proc_dou8vec_minmax,
7294 		.extra1		= (void *)SYSCTL_ZERO,
7295 		.extra2		= (void *)SYSCTL_ONE,
7296 	},
7297 	{
7298 		.procname	= "ioam6_id",
7299 		.data		= &ipv6_devconf.ioam6_id,
7300 		.maxlen		= sizeof(u32),
7301 		.mode		= 0644,
7302 		.proc_handler	= proc_douintvec_minmax,
7303 		.extra1		= (void *)SYSCTL_ZERO,
7304 		.extra2		= (void *)&ioam6_if_id_max,
7305 	},
7306 	{
7307 		.procname	= "ioam6_id_wide",
7308 		.data		= &ipv6_devconf.ioam6_id_wide,
7309 		.maxlen		= sizeof(u32),
7310 		.mode		= 0644,
7311 		.proc_handler	= proc_douintvec,
7312 	},
7313 	{
7314 		.procname	= "ndisc_evict_nocarrier",
7315 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7316 		.maxlen		= sizeof(u8),
7317 		.mode		= 0644,
7318 		.proc_handler	= proc_dou8vec_minmax,
7319 		.extra1		= (void *)SYSCTL_ZERO,
7320 		.extra2		= (void *)SYSCTL_ONE,
7321 	},
7322 	{
7323 		.procname	= "accept_untracked_na",
7324 		.data		= &ipv6_devconf.accept_untracked_na,
7325 		.maxlen		= sizeof(int),
7326 		.mode		= 0644,
7327 		.proc_handler	= proc_dointvec_minmax,
7328 		.extra1		= SYSCTL_ZERO,
7329 		.extra2		= SYSCTL_TWO,
7330 	},
7331 	{
7332 		.procname	= "force_forwarding",
7333 		.data		= &ipv6_devconf.force_forwarding,
7334 		.maxlen		= sizeof(int),
7335 		.mode		= 0644,
7336 		.proc_handler	= addrconf_sysctl_force_forwarding,
7337 	},
7338 };
7339 
7340 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7341 		struct inet6_dev *idev, struct ipv6_devconf *p)
7342 {
7343 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7344 	int i, ifindex;
7345 	struct ctl_table *table;
7346 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7347 
7348 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7349 	if (!table)
7350 		goto out;
7351 
7352 	for (i = 0; i < table_size; i++) {
7353 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7354 		/* If one of these is already set, then it is not safe to
7355 		 * overwrite either of them: this makes proc_dointvec_minmax
7356 		 * usable.
7357 		 */
7358 		if (!table[i].extra1 && !table[i].extra2) {
7359 			table[i].extra1 = idev; /* embedded; no ref */
7360 			table[i].extra2 = net;
7361 		}
7362 	}
7363 
7364 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7365 
7366 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7367 						  table_size);
7368 	if (!p->sysctl_header)
7369 		goto free;
7370 
7371 	if (!strcmp(dev_name, "all"))
7372 		ifindex = NETCONFA_IFINDEX_ALL;
7373 	else if (!strcmp(dev_name, "default"))
7374 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7375 	else
7376 		ifindex = idev->dev->ifindex;
7377 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7378 				     ifindex, p);
7379 	return 0;
7380 
7381 free:
7382 	kfree(table);
7383 out:
7384 	return -ENOBUFS;
7385 }
7386 
7387 static void __addrconf_sysctl_unregister(struct net *net,
7388 					 struct ipv6_devconf *p, int ifindex)
7389 {
7390 	const struct ctl_table *table;
7391 
7392 	if (!p->sysctl_header)
7393 		return;
7394 
7395 	table = p->sysctl_header->ctl_table_arg;
7396 	unregister_net_sysctl_table(p->sysctl_header);
7397 	p->sysctl_header = NULL;
7398 	kfree(table);
7399 
7400 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7401 }
7402 
7403 static int addrconf_sysctl_register(struct inet6_dev *idev)
7404 {
7405 	int err;
7406 
7407 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7408 		return -EINVAL;
7409 
7410 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7411 				    &ndisc_ifinfo_sysctl_change);
7412 	if (err)
7413 		return err;
7414 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7415 					 idev, &idev->cnf);
7416 	if (err)
7417 		neigh_sysctl_unregister(idev->nd_parms);
7418 
7419 	return err;
7420 }
7421 
7422 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7423 {
7424 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7425 				     idev->dev->ifindex);
7426 	neigh_sysctl_unregister(idev->nd_parms);
7427 }
7428 
7429 
7430 #endif
7431 
7432 static int __net_init addrconf_init_net(struct net *net)
7433 {
7434 	int err = -ENOMEM;
7435 	struct ipv6_devconf *all, *dflt;
7436 
7437 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7438 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7439 	net->ipv6.inet6_addr_lst = kzalloc_objs(struct hlist_head,
7440 						IN6_ADDR_HSIZE);
7441 	if (!net->ipv6.inet6_addr_lst)
7442 		goto err_alloc_addr;
7443 
7444 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7445 	if (!all)
7446 		goto err_alloc_all;
7447 
7448 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7449 	if (!dflt)
7450 		goto err_alloc_dflt;
7451 
7452 	if (!net_eq(net, &init_net)) {
7453 		switch (net_inherit_devconf()) {
7454 		case 1:  /* copy from init_net */
7455 			memcpy(all, init_net.ipv6.devconf_all,
7456 			       sizeof(ipv6_devconf));
7457 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7458 			       sizeof(ipv6_devconf_dflt));
7459 			break;
7460 		case 3: /* copy from the current netns */
7461 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7462 			       sizeof(ipv6_devconf));
7463 			memcpy(dflt,
7464 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7465 			       sizeof(ipv6_devconf_dflt));
7466 			break;
7467 		case 0:
7468 		case 2:
7469 			/* use compiled values */
7470 			break;
7471 		}
7472 	}
7473 
7474 	/* these will be inherited by all namespaces */
7475 	dflt->autoconf = ipv6_defaults.autoconf;
7476 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7477 
7478 	dflt->stable_secret.initialized = false;
7479 	all->stable_secret.initialized = false;
7480 
7481 	net->ipv6.devconf_all = all;
7482 	net->ipv6.devconf_dflt = dflt;
7483 
7484 #ifdef CONFIG_SYSCTL
7485 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7486 	if (err < 0)
7487 		goto err_reg_all;
7488 
7489 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7490 	if (err < 0)
7491 		goto err_reg_dflt;
7492 #endif
7493 	return 0;
7494 
7495 #ifdef CONFIG_SYSCTL
7496 err_reg_dflt:
7497 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7498 err_reg_all:
7499 	kfree(dflt);
7500 	net->ipv6.devconf_dflt = NULL;
7501 #endif
7502 err_alloc_dflt:
7503 	kfree(all);
7504 	net->ipv6.devconf_all = NULL;
7505 err_alloc_all:
7506 	kfree(net->ipv6.inet6_addr_lst);
7507 err_alloc_addr:
7508 	return err;
7509 }
7510 
7511 static void __net_exit addrconf_exit_net(struct net *net)
7512 {
7513 	int i;
7514 
7515 #ifdef CONFIG_SYSCTL
7516 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7517 				     NETCONFA_IFINDEX_DEFAULT);
7518 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7519 				     NETCONFA_IFINDEX_ALL);
7520 #endif
7521 	kfree(net->ipv6.devconf_dflt);
7522 	net->ipv6.devconf_dflt = NULL;
7523 	kfree(net->ipv6.devconf_all);
7524 	net->ipv6.devconf_all = NULL;
7525 
7526 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7527 	/*
7528 	 *	Check hash table, then free it.
7529 	 */
7530 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7531 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7532 
7533 	kfree(net->ipv6.inet6_addr_lst);
7534 	net->ipv6.inet6_addr_lst = NULL;
7535 }
7536 
7537 static struct pernet_operations addrconf_ops = {
7538 	.init = addrconf_init_net,
7539 	.exit = addrconf_exit_net,
7540 };
7541 
7542 static struct rtnl_af_ops inet6_ops __read_mostly = {
7543 	.family		  = AF_INET6,
7544 	.fill_link_af	  = inet6_fill_link_af,
7545 	.get_link_af_size = inet6_get_link_af_size,
7546 	.validate_link_af = inet6_validate_link_af,
7547 	.set_link_af	  = inet6_set_link_af,
7548 };
7549 
7550 static const struct rtnl_msg_handler addrconf_rtnl_msg_handlers[] __initconst_or_module = {
7551 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETLINK,
7552 	 .dumpit = inet6_dump_ifinfo, .flags = RTNL_FLAG_DUMP_UNLOCKED},
7553 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDR,
7554 	 .doit = inet6_rtm_newaddr, .flags = RTNL_FLAG_DOIT_PERNET},
7555 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDR,
7556 	 .doit = inet6_rtm_deladdr, .flags = RTNL_FLAG_DOIT_PERNET},
7557 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDR,
7558 	 .doit = inet6_rtm_getaddr, .dumpit = inet6_dump_ifaddr,
7559 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7560 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETMULTICAST,
7561 	 .dumpit = inet6_dump_ifmcaddr,
7562 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7563 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETANYCAST,
7564 	 .dumpit = inet6_dump_ifacaddr,
7565 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7566 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETNETCONF,
7567 	 .doit = inet6_netconf_get_devconf, .dumpit = inet6_netconf_dump_devconf,
7568 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7569 };
7570 
7571 /*
7572  *	Init / cleanup code
7573  */
7574 
7575 int __init addrconf_init(void)
7576 {
7577 	struct inet6_dev *idev;
7578 	int err;
7579 
7580 	err = ipv6_addr_label_init();
7581 	if (err < 0) {
7582 		pr_crit("%s: cannot initialize default policy table: %d\n",
7583 			__func__, err);
7584 		goto out;
7585 	}
7586 
7587 	err = register_pernet_subsys(&addrconf_ops);
7588 	if (err < 0)
7589 		goto out_addrlabel;
7590 
7591 	/* All works using addrconf_wq need to lock rtnl. */
7592 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7593 	if (!addrconf_wq) {
7594 		err = -ENOMEM;
7595 		goto out_nowq;
7596 	}
7597 
7598 	rtnl_net_lock(&init_net);
7599 	idev = ipv6_add_dev(blackhole_netdev);
7600 	rtnl_net_unlock(&init_net);
7601 	if (IS_ERR(idev)) {
7602 		err = PTR_ERR(idev);
7603 		goto errlo;
7604 	}
7605 
7606 	ip6_route_init_special_entries();
7607 
7608 	register_netdevice_notifier(&ipv6_dev_notf);
7609 
7610 	addrconf_verify(&init_net);
7611 
7612 	err = rtnl_af_register(&inet6_ops);
7613 	if (err)
7614 		goto erraf;
7615 
7616 	err = rtnl_register_many(addrconf_rtnl_msg_handlers);
7617 	if (err)
7618 		goto errout;
7619 
7620 	err = ipv6_addr_label_rtnl_register();
7621 	if (err < 0)
7622 		goto errout;
7623 
7624 	return 0;
7625 errout:
7626 	rtnl_unregister_all(PF_INET6);
7627 	rtnl_af_unregister(&inet6_ops);
7628 erraf:
7629 	unregister_netdevice_notifier(&ipv6_dev_notf);
7630 errlo:
7631 	destroy_workqueue(addrconf_wq);
7632 out_nowq:
7633 	unregister_pernet_subsys(&addrconf_ops);
7634 out_addrlabel:
7635 	ipv6_addr_label_cleanup();
7636 out:
7637 	return err;
7638 }
7639 
7640 void addrconf_cleanup(void)
7641 {
7642 	struct net_device *dev;
7643 
7644 	unregister_netdevice_notifier(&ipv6_dev_notf);
7645 	unregister_pernet_subsys(&addrconf_ops);
7646 	ipv6_addr_label_cleanup();
7647 
7648 	rtnl_af_unregister(&inet6_ops);
7649 
7650 	rtnl_net_lock(&init_net);
7651 
7652 	/* clean dev list */
7653 	for_each_netdev(&init_net, dev) {
7654 		if (!__in6_dev_get_rtnl_net(dev))
7655 			continue;
7656 		addrconf_ifdown(dev, true);
7657 	}
7658 	addrconf_ifdown(init_net.loopback_dev, true);
7659 
7660 	rtnl_net_unlock(&init_net);
7661 
7662 	destroy_workqueue(addrconf_wq);
7663 }
7664