xref: /linux/net/ipv6/addrconf.c (revision 7d3ab852dcd853692197a830d20052127754a087)
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_ops_assert_locked(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 1;
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 		rtnl_net_unlock(net);
959 		return 0;
960 	}
961 
962 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
963 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
964 		addrconf_linkdown_change(net, newf);
965 		if ((!newf) ^ (!old))
966 			inet6_netconf_notify_devconf(net,
967 						     RTM_NEWNETCONF,
968 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
969 						     NETCONFA_IFINDEX_ALL,
970 						     net->ipv6.devconf_all);
971 	}
972 
973 	rtnl_net_unlock(net);
974 
975 	return 1;
976 }
977 
978 #endif
979 
980 /* Nobody refers to this ifaddr, destroy it */
981 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
982 {
983 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
984 
985 #ifdef NET_REFCNT_DEBUG
986 	pr_debug("%s\n", __func__);
987 #endif
988 
989 	in6_dev_put(ifp->idev);
990 
991 	if (cancel_delayed_work(&ifp->dad_work))
992 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
993 			  ifp);
994 
995 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
996 		pr_warn("Freeing alive inet6 address %p\n", ifp);
997 		return;
998 	}
999 
1000 	kfree_rcu(ifp, rcu);
1001 }
1002 
1003 static void
1004 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
1005 {
1006 	struct list_head *p;
1007 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1008 
1009 	/*
1010 	 * Each device address list is sorted in order of scope -
1011 	 * global before linklocal.
1012 	 */
1013 	list_for_each(p, &idev->addr_list) {
1014 		struct inet6_ifaddr *ifa
1015 			= list_entry(p, struct inet6_ifaddr, if_list);
1016 		if (ifp_scope > ipv6_addr_src_scope(&ifa->addr))
1017 			break;
1018 	}
1019 
1020 	list_add_tail_rcu(&ifp->if_list, p);
1021 }
1022 
1023 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1024 {
1025 	u32 val = __ipv6_addr_jhash(addr, net_hash_mix(net));
1026 
1027 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1028 }
1029 
1030 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1031 			       struct net_device *dev, unsigned int hash)
1032 {
1033 	struct inet6_ifaddr *ifp;
1034 
1035 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1036 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1037 			if (!dev || ifp->idev->dev == dev)
1038 				return true;
1039 		}
1040 	}
1041 	return false;
1042 }
1043 
1044 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1045 {
1046 	struct net *net = dev_net(dev);
1047 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1048 	int err = 0;
1049 
1050 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1051 
1052 	/* Ignore adding duplicate addresses on an interface */
1053 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1054 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1055 		err = -EEXIST;
1056 	} else {
1057 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1058 	}
1059 
1060 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1061 
1062 	return err;
1063 }
1064 
1065 /* On success it returns ifp with increased reference count */
1066 
1067 static struct inet6_ifaddr *
1068 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1069 	      bool can_block, struct netlink_ext_ack *extack)
1070 {
1071 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1072 	int addr_type = ipv6_addr_type(cfg->pfx);
1073 	struct net *net = dev_net(idev->dev);
1074 	struct inet6_ifaddr *ifa = NULL;
1075 	struct fib6_info *f6i = NULL;
1076 	int err = 0;
1077 
1078 	if (addr_type == IPV6_ADDR_ANY) {
1079 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1080 		return ERR_PTR(-EADDRNOTAVAIL);
1081 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1082 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1083 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1084 		return ERR_PTR(-EADDRNOTAVAIL);
1085 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1086 		   !netif_is_l3_master(idev->dev) &&
1087 		   addr_type & IPV6_ADDR_LOOPBACK) {
1088 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1089 		return ERR_PTR(-EADDRNOTAVAIL);
1090 	}
1091 
1092 	if (idev->dead) {
1093 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1094 		err = -ENODEV;
1095 		goto out;
1096 	}
1097 
1098 	if (idev->cnf.disable_ipv6) {
1099 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1100 		err = -EACCES;
1101 		goto out;
1102 	}
1103 
1104 	/* validator notifier needs to be blocking;
1105 	 * do not call in atomic context
1106 	 */
1107 	if (can_block) {
1108 		struct in6_validator_info i6vi = {
1109 			.i6vi_addr = *cfg->pfx,
1110 			.i6vi_dev = idev,
1111 			.extack = extack,
1112 		};
1113 
1114 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1115 		err = notifier_to_errno(err);
1116 		if (err < 0)
1117 			goto out;
1118 	}
1119 
1120 	ifa = kzalloc_obj(*ifa, gfp_flags | __GFP_ACCOUNT);
1121 	if (!ifa) {
1122 		err = -ENOBUFS;
1123 		goto out;
1124 	}
1125 
1126 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1127 	if (IS_ERR(f6i)) {
1128 		err = PTR_ERR(f6i);
1129 		f6i = NULL;
1130 		goto out;
1131 	}
1132 
1133 	neigh_parms_data_state_setall(idev->nd_parms);
1134 
1135 	ifa->addr = *cfg->pfx;
1136 	if (cfg->peer_pfx)
1137 		ifa->peer_addr = *cfg->peer_pfx;
1138 
1139 	spin_lock_init(&ifa->lock);
1140 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1141 	INIT_HLIST_NODE(&ifa->addr_lst);
1142 	ifa->scope = cfg->scope;
1143 	ifa->prefix_len = cfg->plen;
1144 	ifa->rt_priority = cfg->rt_priority;
1145 	ifa->flags = cfg->ifa_flags;
1146 	ifa->ifa_proto = cfg->ifa_proto;
1147 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1148 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1149 		ifa->flags |= IFA_F_TENTATIVE;
1150 	ifa->valid_lft = cfg->valid_lft;
1151 	ifa->prefered_lft = cfg->preferred_lft;
1152 	ifa->cstamp = ifa->tstamp = jiffies;
1153 	ifa->tokenized = false;
1154 
1155 	ifa->rt = f6i;
1156 
1157 	ifa->idev = idev;
1158 	in6_dev_hold(idev);
1159 
1160 	/* For caller */
1161 	refcount_set(&ifa->refcnt, 1);
1162 
1163 	rcu_read_lock();
1164 
1165 	err = ipv6_add_addr_hash(idev->dev, ifa);
1166 	if (err < 0) {
1167 		rcu_read_unlock();
1168 		goto out;
1169 	}
1170 
1171 	write_lock_bh(&idev->lock);
1172 
1173 	/* Add to inet6_dev unicast addr list. */
1174 	ipv6_link_dev_addr(idev, ifa);
1175 
1176 	if (ifa->flags&IFA_F_TEMPORARY) {
1177 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1178 		in6_ifa_hold(ifa);
1179 	}
1180 
1181 	in6_ifa_hold(ifa);
1182 	write_unlock_bh(&idev->lock);
1183 
1184 	rcu_read_unlock();
1185 
1186 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1187 out:
1188 	if (unlikely(err < 0)) {
1189 		fib6_info_release(f6i);
1190 
1191 		if (ifa) {
1192 			if (ifa->idev)
1193 				in6_dev_put(ifa->idev);
1194 			kfree(ifa);
1195 		}
1196 		ifa = ERR_PTR(err);
1197 	}
1198 
1199 	return ifa;
1200 }
1201 
1202 enum cleanup_prefix_rt_t {
1203 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1204 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1205 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1206 };
1207 
1208 /*
1209  * Check, whether the prefix for ifp would still need a prefix route
1210  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1211  * constants.
1212  *
1213  * 1) we don't purge prefix if address was not permanent.
1214  *    prefix is managed by its own lifetime.
1215  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1216  * 3) if there are no addresses, delete prefix.
1217  * 4) if there are still other permanent address(es),
1218  *    corresponding prefix is still permanent.
1219  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1220  *    don't purge the prefix, assume user space is managing it.
1221  * 6) otherwise, update prefix lifetime to the
1222  *    longest valid lifetime among the corresponding
1223  *    addresses on the device.
1224  *    Note: subsequent RA will update lifetime.
1225  **/
1226 static enum cleanup_prefix_rt_t
1227 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1228 {
1229 	struct inet6_ifaddr *ifa;
1230 	struct inet6_dev *idev = ifp->idev;
1231 	unsigned long lifetime;
1232 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1233 
1234 	*expires = jiffies;
1235 
1236 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1237 		if (ifa == ifp)
1238 			continue;
1239 		if (ifa->prefix_len != ifp->prefix_len ||
1240 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1241 				       ifp->prefix_len))
1242 			continue;
1243 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1244 			return CLEANUP_PREFIX_RT_NOP;
1245 
1246 		action = CLEANUP_PREFIX_RT_EXPIRE;
1247 
1248 		spin_lock(&ifa->lock);
1249 
1250 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1251 		/*
1252 		 * Note: Because this address is
1253 		 * not permanent, lifetime <
1254 		 * LONG_MAX / HZ here.
1255 		 */
1256 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1257 			*expires = ifa->tstamp + lifetime * HZ;
1258 		spin_unlock(&ifa->lock);
1259 	}
1260 
1261 	return action;
1262 }
1263 
1264 static void
1265 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1266 		     bool del_rt, bool del_peer)
1267 {
1268 	struct fib6_table *table;
1269 	struct fib6_info *f6i;
1270 
1271 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1272 					ifp->prefix_len,
1273 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1274 	if (f6i) {
1275 		if (del_rt)
1276 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1277 		else {
1278 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1279 				table = f6i->fib6_table;
1280 				spin_lock_bh(&table->tb6_lock);
1281 
1282 				fib6_set_expires(f6i, expires);
1283 				fib6_add_gc_list(f6i);
1284 
1285 				spin_unlock_bh(&table->tb6_lock);
1286 			}
1287 			fib6_info_release(f6i);
1288 		}
1289 	}
1290 }
1291 
1292 
1293 /* This function wants to get referenced ifp and releases it before return */
1294 
1295 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1296 {
1297 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1298 	struct net *net = dev_net(ifp->idev->dev);
1299 	unsigned long expires;
1300 	int state;
1301 
1302 	ASSERT_RTNL();
1303 
1304 	spin_lock_bh(&ifp->lock);
1305 	state = ifp->state;
1306 	ifp->state = INET6_IFADDR_STATE_DEAD;
1307 	spin_unlock_bh(&ifp->lock);
1308 
1309 	if (state == INET6_IFADDR_STATE_DEAD)
1310 		goto out;
1311 
1312 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1313 	hlist_del_init_rcu(&ifp->addr_lst);
1314 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1315 
1316 	write_lock_bh(&ifp->idev->lock);
1317 
1318 	if (ifp->flags&IFA_F_TEMPORARY) {
1319 		list_del(&ifp->tmp_list);
1320 		if (ifp->ifpub) {
1321 			in6_ifa_put(ifp->ifpub);
1322 			ifp->ifpub = NULL;
1323 		}
1324 		__in6_ifa_put(ifp);
1325 	}
1326 
1327 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE))
1328 		action = check_cleanup_prefix_route(ifp, &expires);
1329 
1330 	list_del_rcu(&ifp->if_list);
1331 	__in6_ifa_put(ifp);
1332 
1333 	write_unlock_bh(&ifp->idev->lock);
1334 
1335 	addrconf_del_dad_work(ifp);
1336 
1337 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1338 
1339 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1340 
1341 	if (action != CLEANUP_PREFIX_RT_NOP) {
1342 		cleanup_prefix_route(ifp, expires,
1343 			action == CLEANUP_PREFIX_RT_DEL, false);
1344 	}
1345 
1346 	/* clean up prefsrc entries */
1347 	rt6_remove_prefsrc(ifp);
1348 out:
1349 	in6_ifa_put(ifp);
1350 }
1351 
1352 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1353 {
1354 	return READ_ONCE(idev->cnf.regen_min_advance) +
1355 		READ_ONCE(idev->cnf.regen_max_retry) *
1356 		READ_ONCE(idev->cnf.dad_transmits) *
1357 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1358 }
1359 
1360 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1361 {
1362 	struct inet6_dev *idev = ifp->idev;
1363 	unsigned long tmp_tstamp, age;
1364 	unsigned long regen_advance;
1365 	unsigned long now = jiffies;
1366 	u32 if_public_preferred_lft;
1367 	s32 cnf_temp_preferred_lft;
1368 	struct inet6_ifaddr *ift;
1369 	struct ifa6_config cfg;
1370 	long max_desync_factor;
1371 	struct in6_addr addr;
1372 	int ret = 0;
1373 
1374 	write_lock_bh(&idev->lock);
1375 
1376 retry:
1377 	in6_dev_hold(idev);
1378 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1379 		write_unlock_bh(&idev->lock);
1380 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1381 		in6_dev_put(idev);
1382 		ret = -1;
1383 		goto out;
1384 	}
1385 	spin_lock_bh(&ifp->lock);
1386 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1387 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1388 		spin_unlock_bh(&ifp->lock);
1389 		write_unlock_bh(&idev->lock);
1390 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1391 			__func__);
1392 		in6_dev_put(idev);
1393 		ret = -1;
1394 		goto out;
1395 	}
1396 	in6_ifa_hold(ifp);
1397 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1398 	ipv6_gen_rnd_iid(&addr);
1399 
1400 	age = (now - ifp->tstamp) / HZ;
1401 
1402 	regen_advance = ipv6_get_regen_advance(idev);
1403 
1404 	/* recalculate max_desync_factor each time and update
1405 	 * idev->desync_factor if it's larger
1406 	 */
1407 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1408 	max_desync_factor = min_t(long,
1409 				  READ_ONCE(idev->cnf.max_desync_factor),
1410 				  cnf_temp_preferred_lft - regen_advance);
1411 
1412 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1413 		if (max_desync_factor > 0) {
1414 			get_random_bytes(&idev->desync_factor,
1415 					 sizeof(idev->desync_factor));
1416 			idev->desync_factor %= max_desync_factor;
1417 		} else {
1418 			idev->desync_factor = 0;
1419 		}
1420 	}
1421 
1422 	if_public_preferred_lft = ifp->prefered_lft;
1423 
1424 	memset(&cfg, 0, sizeof(cfg));
1425 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1426 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1427 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1428 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1429 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1430 
1431 	cfg.plen = ifp->prefix_len;
1432 	tmp_tstamp = ifp->tstamp;
1433 	spin_unlock_bh(&ifp->lock);
1434 
1435 	write_unlock_bh(&idev->lock);
1436 
1437 	/* From RFC 4941:
1438 	 *
1439 	 *     A temporary address is created only if this calculated Preferred
1440 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1441 	 *     particular, an implementation must not create a temporary address
1442 	 *     with a zero Preferred Lifetime.
1443 	 *
1444 	 *     ...
1445 	 *
1446 	 *     When creating a temporary address, the lifetime values MUST be
1447 	 *     derived from the corresponding prefix as follows:
1448 	 *
1449 	 *     ...
1450 	 *
1451 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1452 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1453 	 *        DESYNC_FACTOR.
1454 	 *
1455 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1456 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1457 	 * ifp->prefered_lft.
1458 	 *
1459 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1460 	 * temporary addresses being generated.
1461 	 */
1462 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1463 	if (cfg.preferred_lft <= regen_advance + age) {
1464 		cfg.preferred_lft = regen_advance + age + 1;
1465 		if (cfg.preferred_lft > cfg.valid_lft ||
1466 		    cfg.preferred_lft > if_public_preferred_lft) {
1467 			in6_ifa_put(ifp);
1468 			in6_dev_put(idev);
1469 			ret = -1;
1470 			goto out;
1471 		}
1472 	}
1473 
1474 	cfg.ifa_flags = IFA_F_TEMPORARY;
1475 	/* set in addrconf_prefix_rcv() */
1476 	if (ifp->flags & IFA_F_OPTIMISTIC)
1477 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1478 
1479 	cfg.pfx = &addr;
1480 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1481 
1482 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1483 	if (IS_ERR(ift)) {
1484 		in6_ifa_put(ifp);
1485 		in6_dev_put(idev);
1486 		pr_info("%s: retry temporary address regeneration\n", __func__);
1487 		write_lock_bh(&idev->lock);
1488 		goto retry;
1489 	}
1490 
1491 	spin_lock_bh(&ift->lock);
1492 	ift->ifpub = ifp;
1493 	ift->cstamp = now;
1494 	ift->tstamp = tmp_tstamp;
1495 	spin_unlock_bh(&ift->lock);
1496 
1497 	addrconf_dad_start(ift);
1498 	in6_ifa_put(ift);
1499 	in6_dev_put(idev);
1500 out:
1501 	return ret;
1502 }
1503 
1504 /*
1505  *	Choose an appropriate source address (RFC3484)
1506  */
1507 enum {
1508 	IPV6_SADDR_RULE_INIT = 0,
1509 	IPV6_SADDR_RULE_LOCAL,
1510 	IPV6_SADDR_RULE_SCOPE,
1511 	IPV6_SADDR_RULE_PREFERRED,
1512 #ifdef CONFIG_IPV6_MIP6
1513 	IPV6_SADDR_RULE_HOA,
1514 #endif
1515 	IPV6_SADDR_RULE_OIF,
1516 	IPV6_SADDR_RULE_LABEL,
1517 	IPV6_SADDR_RULE_PRIVACY,
1518 	IPV6_SADDR_RULE_ORCHID,
1519 	IPV6_SADDR_RULE_PREFIX,
1520 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1521 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1522 #endif
1523 	IPV6_SADDR_RULE_MAX
1524 };
1525 
1526 struct ipv6_saddr_score {
1527 	int			rule;
1528 	int			addr_type;
1529 	struct inet6_ifaddr	*ifa;
1530 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1531 	int			scopedist;
1532 	int			matchlen;
1533 };
1534 
1535 struct ipv6_saddr_dst {
1536 	const struct in6_addr *addr;
1537 	int ifindex;
1538 	int scope;
1539 	int label;
1540 	unsigned int prefs;
1541 };
1542 
1543 static inline int ipv6_saddr_preferred(int type)
1544 {
1545 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1546 		return 1;
1547 	return 0;
1548 }
1549 
1550 static bool ipv6_use_optimistic_addr(const struct net *net,
1551 				     const struct inet6_dev *idev)
1552 {
1553 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1554 	if (!idev)
1555 		return false;
1556 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1557 	    !READ_ONCE(idev->cnf.optimistic_dad))
1558 		return false;
1559 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1560 	    !READ_ONCE(idev->cnf.use_optimistic))
1561 		return false;
1562 
1563 	return true;
1564 #else
1565 	return false;
1566 #endif
1567 }
1568 
1569 static bool ipv6_allow_optimistic_dad(const struct net *net,
1570 				      const struct inet6_dev *idev)
1571 {
1572 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1573 	if (!idev)
1574 		return false;
1575 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1576 	    !READ_ONCE(idev->cnf.optimistic_dad))
1577 		return false;
1578 
1579 	return true;
1580 #else
1581 	return false;
1582 #endif
1583 }
1584 
1585 static int ipv6_get_saddr_eval(struct net *net,
1586 			       struct ipv6_saddr_score *score,
1587 			       struct ipv6_saddr_dst *dst,
1588 			       int i)
1589 {
1590 	int ret;
1591 
1592 	if (i <= score->rule) {
1593 		switch (i) {
1594 		case IPV6_SADDR_RULE_SCOPE:
1595 			ret = score->scopedist;
1596 			break;
1597 		case IPV6_SADDR_RULE_PREFIX:
1598 			ret = score->matchlen;
1599 			break;
1600 		default:
1601 			ret = !!test_bit(i, score->scorebits);
1602 		}
1603 		goto out;
1604 	}
1605 
1606 	switch (i) {
1607 	case IPV6_SADDR_RULE_INIT:
1608 		/* Rule 0: remember if hiscore is not ready yet */
1609 		ret = !!score->ifa;
1610 		break;
1611 	case IPV6_SADDR_RULE_LOCAL:
1612 		/* Rule 1: Prefer same address */
1613 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1614 		break;
1615 	case IPV6_SADDR_RULE_SCOPE:
1616 		/* Rule 2: Prefer appropriate scope
1617 		 *
1618 		 *      ret
1619 		 *       ^
1620 		 *    -1 |  d 15
1621 		 *    ---+--+-+---> scope
1622 		 *       |
1623 		 *       |             d is scope of the destination.
1624 		 *  B-d  |  \
1625 		 *       |   \      <- smaller scope is better if
1626 		 *  B-15 |    \        if scope is enough for destination.
1627 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1628 		 * d-C-1 | /
1629 		 *       |/         <- greater is better
1630 		 *   -C  /             if scope is not enough for destination.
1631 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1632 		 *
1633 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1634 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1635 		 * Assume B = 0 and we get C > 29.
1636 		 */
1637 		ret = __ipv6_addr_src_scope(score->addr_type);
1638 		if (ret >= dst->scope)
1639 			ret = -ret;
1640 		else
1641 			ret -= 128;	/* 30 is enough */
1642 		score->scopedist = ret;
1643 		break;
1644 	case IPV6_SADDR_RULE_PREFERRED:
1645 	    {
1646 		/* Rule 3: Avoid deprecated and optimistic addresses */
1647 		u8 avoid = IFA_F_DEPRECATED;
1648 
1649 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1650 			avoid |= IFA_F_OPTIMISTIC;
1651 		ret = ipv6_saddr_preferred(score->addr_type) ||
1652 		      !(score->ifa->flags & avoid);
1653 		break;
1654 	    }
1655 #ifdef CONFIG_IPV6_MIP6
1656 	case IPV6_SADDR_RULE_HOA:
1657 	    {
1658 		/* Rule 4: Prefer home address */
1659 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1660 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1661 		break;
1662 	    }
1663 #endif
1664 	case IPV6_SADDR_RULE_OIF:
1665 		/* Rule 5: Prefer outgoing interface */
1666 		ret = (!dst->ifindex ||
1667 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1668 		break;
1669 	case IPV6_SADDR_RULE_LABEL:
1670 		/* Rule 6: Prefer matching label */
1671 		ret = ipv6_addr_label(net,
1672 				      &score->ifa->addr, score->addr_type,
1673 				      score->ifa->idev->dev->ifindex) == dst->label;
1674 		break;
1675 	case IPV6_SADDR_RULE_PRIVACY:
1676 	    {
1677 		/* Rule 7: Prefer public address
1678 		 * Note: prefer temporary address if use_tempaddr >= 2
1679 		 */
1680 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1681 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1682 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1683 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1684 		break;
1685 	    }
1686 	case IPV6_SADDR_RULE_ORCHID:
1687 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1688 		 *	    non-ORCHID vs non-ORCHID
1689 		 */
1690 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1691 			ipv6_addr_orchid(dst->addr));
1692 		break;
1693 	case IPV6_SADDR_RULE_PREFIX:
1694 		/* Rule 8: Use longest matching prefix */
1695 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1696 		if (ret > score->ifa->prefix_len)
1697 			ret = score->ifa->prefix_len;
1698 		score->matchlen = ret;
1699 		break;
1700 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1701 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1702 		/* Optimistic addresses still have lower precedence than other
1703 		 * preferred addresses.
1704 		 */
1705 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1706 		break;
1707 #endif
1708 	default:
1709 		ret = 0;
1710 	}
1711 
1712 	if (ret)
1713 		__set_bit(i, score->scorebits);
1714 	score->rule = i;
1715 out:
1716 	return ret;
1717 }
1718 
1719 static int __ipv6_dev_get_saddr(struct net *net,
1720 				struct ipv6_saddr_dst *dst,
1721 				struct inet6_dev *idev,
1722 				struct ipv6_saddr_score *scores,
1723 				int hiscore_idx)
1724 {
1725 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1726 
1727 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1728 		int i;
1729 
1730 		/*
1731 		 * - Tentative Address (RFC2462 section 5.4)
1732 		 *  - A tentative address is not considered
1733 		 *    "assigned to an interface" in the traditional
1734 		 *    sense, unless it is also flagged as optimistic.
1735 		 * - Candidate Source Address (section 4)
1736 		 *  - In any case, anycast addresses, multicast
1737 		 *    addresses, and the unspecified address MUST
1738 		 *    NOT be included in a candidate set.
1739 		 */
1740 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1741 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1742 			continue;
1743 
1744 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1745 
1746 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1747 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1748 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1749 					    idev->dev->name);
1750 			continue;
1751 		}
1752 
1753 		score->rule = -1;
1754 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1755 
1756 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1757 			int minihiscore, miniscore;
1758 
1759 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1760 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1761 
1762 			if (minihiscore > miniscore) {
1763 				if (i == IPV6_SADDR_RULE_SCOPE &&
1764 				    score->scopedist > 0) {
1765 					/*
1766 					 * special case:
1767 					 * each remaining entry
1768 					 * has too small (not enough)
1769 					 * scope, because ifa entries
1770 					 * are sorted by their scope
1771 					 * values.
1772 					 */
1773 					goto out;
1774 				}
1775 				break;
1776 			} else if (minihiscore < miniscore) {
1777 				swap(hiscore, score);
1778 				hiscore_idx = 1 - hiscore_idx;
1779 
1780 				/* restore our iterator */
1781 				score->ifa = hiscore->ifa;
1782 
1783 				break;
1784 			}
1785 		}
1786 	}
1787 out:
1788 	return hiscore_idx;
1789 }
1790 
1791 static int ipv6_get_saddr_master(struct net *net,
1792 				 const struct net_device *dst_dev,
1793 				 const struct net_device *master,
1794 				 struct ipv6_saddr_dst *dst,
1795 				 struct ipv6_saddr_score *scores,
1796 				 int hiscore_idx)
1797 {
1798 	struct inet6_dev *idev;
1799 
1800 	idev = __in6_dev_get(dst_dev);
1801 	if (idev)
1802 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1803 						   scores, hiscore_idx);
1804 
1805 	idev = __in6_dev_get(master);
1806 	if (idev)
1807 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1808 						   scores, hiscore_idx);
1809 
1810 	return hiscore_idx;
1811 }
1812 
1813 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1814 		       const struct in6_addr *daddr, unsigned int prefs,
1815 		       struct in6_addr *saddr)
1816 {
1817 	struct ipv6_saddr_score scores[2], *hiscore;
1818 	struct ipv6_saddr_dst dst;
1819 	struct inet6_dev *idev;
1820 	struct net_device *dev;
1821 	int dst_type;
1822 	bool use_oif_addr = false;
1823 	int hiscore_idx = 0;
1824 	int ret = 0;
1825 
1826 	dst_type = __ipv6_addr_type(daddr);
1827 	dst.addr = daddr;
1828 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1829 	dst.scope = __ipv6_addr_src_scope(dst_type);
1830 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1831 	dst.prefs = prefs;
1832 
1833 	scores[hiscore_idx].rule = -1;
1834 	scores[hiscore_idx].ifa = NULL;
1835 
1836 	rcu_read_lock();
1837 
1838 	/* Candidate Source Address (section 4)
1839 	 *  - multicast and link-local destination address,
1840 	 *    the set of candidate source address MUST only
1841 	 *    include addresses assigned to interfaces
1842 	 *    belonging to the same link as the outgoing
1843 	 *    interface.
1844 	 * (- For site-local destination addresses, the
1845 	 *    set of candidate source addresses MUST only
1846 	 *    include addresses assigned to interfaces
1847 	 *    belonging to the same site as the outgoing
1848 	 *    interface.)
1849 	 *  - "It is RECOMMENDED that the candidate source addresses
1850 	 *    be the set of unicast addresses assigned to the
1851 	 *    interface that will be used to send to the destination
1852 	 *    (the 'outgoing' interface)." (RFC 6724)
1853 	 */
1854 	if (dst_dev) {
1855 		idev = __in6_dev_get(dst_dev);
1856 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1857 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1858 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1859 			use_oif_addr = true;
1860 		}
1861 	}
1862 
1863 	if (use_oif_addr) {
1864 		if (idev)
1865 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1866 	} else {
1867 		const struct net_device *master;
1868 		int master_idx = 0;
1869 
1870 		/* if dst_dev exists and is enslaved to an L3 device, then
1871 		 * prefer addresses from dst_dev and then the master over
1872 		 * any other enslaved devices in the L3 domain.
1873 		 */
1874 		master = l3mdev_master_dev_rcu(dst_dev);
1875 		if (master) {
1876 			master_idx = master->ifindex;
1877 
1878 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1879 							    master, &dst,
1880 							    scores, hiscore_idx);
1881 
1882 			if (scores[hiscore_idx].ifa &&
1883 			    scores[hiscore_idx].scopedist >= 0)
1884 				goto out;
1885 		}
1886 
1887 		for_each_netdev_rcu(net, dev) {
1888 			/* only consider addresses on devices in the
1889 			 * same L3 domain
1890 			 */
1891 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1892 				continue;
1893 			idev = __in6_dev_get(dev);
1894 			if (!idev)
1895 				continue;
1896 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1897 		}
1898 	}
1899 
1900 out:
1901 	hiscore = &scores[hiscore_idx];
1902 	if (!hiscore->ifa)
1903 		ret = -EADDRNOTAVAIL;
1904 	else
1905 		*saddr = hiscore->ifa->addr;
1906 
1907 	rcu_read_unlock();
1908 	return ret;
1909 }
1910 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1911 
1912 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1913 			      u32 banned_flags)
1914 {
1915 	struct inet6_ifaddr *ifp;
1916 	int err = -EADDRNOTAVAIL;
1917 
1918 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1919 		if (ifp->scope > IFA_LINK)
1920 			break;
1921 		if (ifp->scope == IFA_LINK &&
1922 		    !(ifp->flags & banned_flags)) {
1923 			*addr = ifp->addr;
1924 			err = 0;
1925 			break;
1926 		}
1927 	}
1928 	return err;
1929 }
1930 
1931 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1932 		    u32 banned_flags)
1933 {
1934 	struct inet6_dev *idev;
1935 	int err = -EADDRNOTAVAIL;
1936 
1937 	rcu_read_lock();
1938 	idev = __in6_dev_get(dev);
1939 	if (idev) {
1940 		read_lock_bh(&idev->lock);
1941 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1942 		read_unlock_bh(&idev->lock);
1943 	}
1944 	rcu_read_unlock();
1945 	return err;
1946 }
1947 
1948 static int ipv6_count_addresses(const struct inet6_dev *idev)
1949 {
1950 	const struct inet6_ifaddr *ifp;
1951 	int cnt = 0;
1952 
1953 	rcu_read_lock();
1954 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1955 		cnt++;
1956 	rcu_read_unlock();
1957 	return cnt;
1958 }
1959 
1960 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1961 		  const struct net_device *dev, int strict)
1962 {
1963 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1964 				       strict, IFA_F_TENTATIVE);
1965 }
1966 EXPORT_SYMBOL(ipv6_chk_addr);
1967 
1968 /* device argument is used to find the L3 domain of interest. If
1969  * skip_dev_check is set, then the ifp device is not checked against
1970  * the passed in dev argument. So the 2 cases for addresses checks are:
1971  *   1. does the address exist in the L3 domain that dev is part of
1972  *      (skip_dev_check = true), or
1973  *
1974  *   2. does the address exist on the specific device
1975  *      (skip_dev_check = false)
1976  */
1977 static struct net_device *
1978 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1979 			  const struct net_device *dev, bool skip_dev_check,
1980 			  int strict, u32 banned_flags)
1981 {
1982 	unsigned int hash = inet6_addr_hash(net, addr);
1983 	struct net_device *l3mdev, *ndev;
1984 	struct inet6_ifaddr *ifp;
1985 	u32 ifp_flags;
1986 
1987 	rcu_read_lock();
1988 
1989 	l3mdev = l3mdev_master_dev_rcu(dev);
1990 	if (skip_dev_check)
1991 		dev = NULL;
1992 
1993 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1994 		ndev = ifp->idev->dev;
1995 
1996 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1997 			continue;
1998 
1999 		/* Decouple optimistic from tentative for evaluation here.
2000 		 * Ban optimistic addresses explicitly, when required.
2001 		 */
2002 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
2003 			    ? (ifp->flags&~IFA_F_TENTATIVE)
2004 			    : ifp->flags;
2005 		if (ipv6_addr_equal(&ifp->addr, addr) &&
2006 		    !(ifp_flags&banned_flags) &&
2007 		    (!dev || ndev == dev ||
2008 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2009 			rcu_read_unlock();
2010 			return ndev;
2011 		}
2012 	}
2013 
2014 	rcu_read_unlock();
2015 	return NULL;
2016 }
2017 
2018 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2019 			    const struct net_device *dev, bool skip_dev_check,
2020 			    int strict, u32 banned_flags)
2021 {
2022 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2023 					 strict, banned_flags) ? 1 : 0;
2024 }
2025 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2026 
2027 
2028 /* Compares an address/prefix_len with addresses on device @dev.
2029  * If one is found it returns true.
2030  */
2031 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2032 	const unsigned int prefix_len, struct net_device *dev)
2033 {
2034 	const struct inet6_ifaddr *ifa;
2035 	const struct inet6_dev *idev;
2036 	bool ret = false;
2037 
2038 	rcu_read_lock();
2039 	idev = __in6_dev_get(dev);
2040 	if (idev) {
2041 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2042 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2043 			if (ret)
2044 				break;
2045 		}
2046 	}
2047 	rcu_read_unlock();
2048 
2049 	return ret;
2050 }
2051 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2052 
2053 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2054 {
2055 	const struct inet6_ifaddr *ifa;
2056 	const struct inet6_dev *idev;
2057 	int	onlink;
2058 
2059 	onlink = 0;
2060 	rcu_read_lock();
2061 	idev = __in6_dev_get(dev);
2062 	if (idev) {
2063 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2064 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2065 						   ifa->prefix_len);
2066 			if (onlink)
2067 				break;
2068 		}
2069 	}
2070 	rcu_read_unlock();
2071 	return onlink;
2072 }
2073 EXPORT_SYMBOL(ipv6_chk_prefix);
2074 
2075 /**
2076  * ipv6_dev_find - find the first device with a given source address.
2077  * @net: the net namespace
2078  * @addr: the source address
2079  * @dev: used to find the L3 domain of interest
2080  *
2081  * The caller should be protected by RCU, or RTNL.
2082  */
2083 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2084 				 struct net_device *dev)
2085 {
2086 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2087 					 IFA_F_TENTATIVE);
2088 }
2089 EXPORT_SYMBOL(ipv6_dev_find);
2090 
2091 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2092 				     struct net_device *dev, int strict)
2093 {
2094 	unsigned int hash = inet6_addr_hash(net, addr);
2095 	struct inet6_ifaddr *ifp, *result = NULL;
2096 
2097 	rcu_read_lock();
2098 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2099 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2100 			if (!dev || ifp->idev->dev == dev ||
2101 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2102 				if (in6_ifa_hold_safe(ifp)) {
2103 					result = ifp;
2104 					break;
2105 				}
2106 			}
2107 		}
2108 	}
2109 	rcu_read_unlock();
2110 
2111 	return result;
2112 }
2113 
2114 /* Gets referenced address, destroys ifaddr */
2115 
2116 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2117 {
2118 	if (dad_failed)
2119 		ifp->flags |= IFA_F_DADFAILED;
2120 
2121 	if (ifp->flags&IFA_F_TEMPORARY) {
2122 		struct inet6_ifaddr *ifpub;
2123 		spin_lock_bh(&ifp->lock);
2124 		ifpub = ifp->ifpub;
2125 		if (ifpub) {
2126 			in6_ifa_hold(ifpub);
2127 			spin_unlock_bh(&ifp->lock);
2128 			ipv6_create_tempaddr(ifpub, true);
2129 			in6_ifa_put(ifpub);
2130 		} else {
2131 			spin_unlock_bh(&ifp->lock);
2132 		}
2133 		ipv6_del_addr(ifp);
2134 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2135 		spin_lock_bh(&ifp->lock);
2136 		addrconf_del_dad_work(ifp);
2137 		ifp->flags |= IFA_F_TENTATIVE;
2138 		if (dad_failed)
2139 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2140 		spin_unlock_bh(&ifp->lock);
2141 		if (dad_failed)
2142 			ipv6_ifa_notify(0, ifp);
2143 		in6_ifa_put(ifp);
2144 	} else {
2145 		ipv6_del_addr(ifp);
2146 	}
2147 }
2148 
2149 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2150 {
2151 	int err = -ENOENT;
2152 
2153 	spin_lock_bh(&ifp->lock);
2154 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2155 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2156 		err = 0;
2157 	}
2158 	spin_unlock_bh(&ifp->lock);
2159 
2160 	return err;
2161 }
2162 
2163 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2164 {
2165 	struct inet6_dev *idev = ifp->idev;
2166 	struct net *net = dev_net(idev->dev);
2167 	int max_addresses;
2168 
2169 	spin_lock_bh(&ifp->lock);
2170 
2171 	if (ifp->state != INET6_IFADDR_STATE_DAD) {
2172 		spin_unlock_bh(&ifp->lock);
2173 		in6_ifa_put(ifp);
2174 		return;
2175 	}
2176 	ifp->state = INET6_IFADDR_STATE_POSTDAD;
2177 
2178 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2179 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2180 
2181 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2182 		struct in6_addr new_addr;
2183 		struct inet6_ifaddr *ifp2;
2184 		int retries = ifp->stable_privacy_retry + 1;
2185 		struct ifa6_config cfg = {
2186 			.pfx = &new_addr,
2187 			.plen = ifp->prefix_len,
2188 			.ifa_flags = ifp->flags,
2189 			.valid_lft = ifp->valid_lft,
2190 			.preferred_lft = ifp->prefered_lft,
2191 			.scope = ifp->scope,
2192 		};
2193 
2194 		if (retries > net->ipv6.sysctl.idgen_retries) {
2195 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2196 					     ifp->idev->dev->name);
2197 			goto errdad;
2198 		}
2199 
2200 		new_addr = ifp->addr;
2201 		if (ipv6_generate_stable_address(&new_addr, retries,
2202 						 idev))
2203 			goto errdad;
2204 
2205 		spin_unlock_bh(&ifp->lock);
2206 
2207 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2208 		if (max_addresses &&
2209 		    ipv6_count_addresses(idev) >= max_addresses)
2210 			goto lock_errdad;
2211 
2212 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2213 				     ifp->idev->dev->name);
2214 
2215 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2216 		if (IS_ERR(ifp2))
2217 			goto lock_errdad;
2218 
2219 		spin_lock_bh(&ifp2->lock);
2220 		ifp2->stable_privacy_retry = retries;
2221 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2222 		spin_unlock_bh(&ifp2->lock);
2223 
2224 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2225 		in6_ifa_put(ifp2);
2226 lock_errdad:
2227 		spin_lock_bh(&ifp->lock);
2228 		if (ifp->state != INET6_IFADDR_STATE_POSTDAD) {
2229 			spin_unlock_bh(&ifp->lock);
2230 			in6_ifa_put(ifp);
2231 			return;
2232 		}
2233 	}
2234 
2235 errdad:
2236 	/* transition from _POSTDAD to _ERRDAD */
2237 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2238 	spin_unlock_bh(&ifp->lock);
2239 
2240 	addrconf_mod_dad_work(ifp, 0);
2241 	in6_ifa_put(ifp);
2242 }
2243 
2244 /* Join to solicited addr multicast group. */
2245 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2246 {
2247 	struct in6_addr maddr;
2248 
2249 	if (READ_ONCE(dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2250 		return;
2251 
2252 	addrconf_addr_solict_mult(addr, &maddr);
2253 	ipv6_dev_mc_inc(dev, &maddr);
2254 }
2255 
2256 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2257 {
2258 	struct in6_addr maddr;
2259 
2260 	if (READ_ONCE(idev->dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2261 		return;
2262 
2263 	addrconf_addr_solict_mult(addr, &maddr);
2264 	__ipv6_dev_mc_dec(idev, &maddr);
2265 }
2266 
2267 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2268 {
2269 	struct in6_addr addr;
2270 
2271 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2272 		return;
2273 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2274 	if (ipv6_addr_any(&addr))
2275 		return;
2276 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2277 }
2278 
2279 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2280 {
2281 	struct in6_addr addr;
2282 
2283 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2284 		return;
2285 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2286 	if (ipv6_addr_any(&addr))
2287 		return;
2288 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2289 }
2290 
2291 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2292 {
2293 	switch (dev->addr_len) {
2294 	case ETH_ALEN:
2295 		memcpy(eui, dev->dev_addr, 3);
2296 		eui[3] = 0xFF;
2297 		eui[4] = 0xFE;
2298 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2299 		break;
2300 	case EUI64_ADDR_LEN:
2301 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2302 		eui[0] ^= 2;
2303 		break;
2304 	default:
2305 		return -1;
2306 	}
2307 
2308 	return 0;
2309 }
2310 
2311 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2312 {
2313 	const union fwnet_hwaddr *ha;
2314 
2315 	if (dev->addr_len != FWNET_ALEN)
2316 		return -1;
2317 
2318 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2319 
2320 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2321 	eui[0] ^= 2;
2322 	return 0;
2323 }
2324 
2325 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2326 {
2327 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2328 	if (dev->addr_len != ARCNET_ALEN)
2329 		return -1;
2330 	memset(eui, 0, 7);
2331 	eui[7] = *(u8 *)dev->dev_addr;
2332 	return 0;
2333 }
2334 
2335 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2336 {
2337 	if (dev->addr_len != INFINIBAND_ALEN)
2338 		return -1;
2339 	memcpy(eui, dev->dev_addr + 12, 8);
2340 	eui[0] |= 2;
2341 	return 0;
2342 }
2343 
2344 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2345 {
2346 	if (addr == 0)
2347 		return -1;
2348 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2349 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2350 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2351 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2352 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2353 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2354 	eui[1] = 0;
2355 	eui[2] = 0x5E;
2356 	eui[3] = 0xFE;
2357 	memcpy(eui + 4, &addr, 4);
2358 	return 0;
2359 }
2360 
2361 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2362 {
2363 	if (dev->priv_flags & IFF_ISATAP)
2364 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2365 	return -1;
2366 }
2367 
2368 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2369 {
2370 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2371 }
2372 
2373 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2374 {
2375 	memcpy(eui, dev->perm_addr, 3);
2376 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2377 	eui[3] = 0xFF;
2378 	eui[4] = 0xFE;
2379 	eui[0] ^= 2;
2380 	return 0;
2381 }
2382 
2383 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2384 {
2385 	switch (dev->type) {
2386 	case ARPHRD_ETHER:
2387 	case ARPHRD_FDDI:
2388 		return addrconf_ifid_eui48(eui, dev);
2389 	case ARPHRD_ARCNET:
2390 		return addrconf_ifid_arcnet(eui, dev);
2391 	case ARPHRD_INFINIBAND:
2392 		return addrconf_ifid_infiniband(eui, dev);
2393 	case ARPHRD_SIT:
2394 		return addrconf_ifid_sit(eui, dev);
2395 	case ARPHRD_IPGRE:
2396 	case ARPHRD_TUNNEL:
2397 		return addrconf_ifid_gre(eui, dev);
2398 	case ARPHRD_6LOWPAN:
2399 		return addrconf_ifid_6lowpan(eui, dev);
2400 	case ARPHRD_IEEE1394:
2401 		return addrconf_ifid_ieee1394(eui, dev);
2402 	case ARPHRD_TUNNEL6:
2403 	case ARPHRD_IP6GRE:
2404 	case ARPHRD_RAWIP:
2405 		return addrconf_ifid_ip6tnl(eui, dev);
2406 	}
2407 	return -1;
2408 }
2409 
2410 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2411 {
2412 	int err = -1;
2413 	struct inet6_ifaddr *ifp;
2414 
2415 	read_lock_bh(&idev->lock);
2416 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2417 		if (ifp->scope > IFA_LINK)
2418 			break;
2419 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2420 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2421 			err = 0;
2422 			break;
2423 		}
2424 	}
2425 	read_unlock_bh(&idev->lock);
2426 	return err;
2427 }
2428 
2429 /* Generation of a randomized Interface Identifier
2430  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2431  */
2432 
2433 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2434 {
2435 regen:
2436 	get_random_bytes(&addr->s6_addr[8], 8);
2437 
2438 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2439 	 * check if generated address is not inappropriate:
2440 	 *
2441 	 * - Reserved IPv6 Interface Identifiers
2442 	 * - XXX: already assigned to an address on the device
2443 	 */
2444 
2445 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2446 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2447 		goto regen;
2448 
2449 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2450 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2451 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2452 	 */
2453 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2454 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2455 		goto regen;
2456 
2457 	/* Reserved subnet anycast addresses */
2458 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2459 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2460 		goto regen;
2461 }
2462 
2463 /*
2464  *	Add prefix route.
2465  */
2466 
2467 static void
2468 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2469 		      struct net_device *dev, unsigned long expires,
2470 		      u32 flags, gfp_t gfp_flags)
2471 {
2472 	struct fib6_config cfg = {
2473 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2474 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2475 		.fc_ifindex = dev->ifindex,
2476 		.fc_expires = expires,
2477 		.fc_dst_len = plen,
2478 		.fc_flags = RTF_UP | flags,
2479 		.fc_nlinfo.nl_net = dev_net(dev),
2480 		.fc_protocol = RTPROT_KERNEL,
2481 		.fc_type = RTN_UNICAST,
2482 	};
2483 
2484 	cfg.fc_dst = *pfx;
2485 
2486 	/* Prevent useless cloning on PtP SIT.
2487 	   This thing is done here expecting that the whole
2488 	   class of non-broadcast devices need not cloning.
2489 	 */
2490 #if IS_ENABLED(CONFIG_IPV6_SIT)
2491 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2492 		cfg.fc_flags |= RTF_NONEXTHOP;
2493 #endif
2494 
2495 	ip6_route_add(&cfg, gfp_flags, NULL);
2496 }
2497 
2498 
2499 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2500 						  int plen,
2501 						  const struct net_device *dev,
2502 						  u32 flags, u32 noflags,
2503 						  bool no_gw)
2504 {
2505 	struct fib6_node *fn;
2506 	struct fib6_info *rt = NULL;
2507 	struct fib6_table *table;
2508 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2509 
2510 	table = fib6_get_table(dev_net(dev), tb_id);
2511 	if (!table)
2512 		return NULL;
2513 
2514 	rcu_read_lock();
2515 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2516 	if (!fn)
2517 		goto out;
2518 
2519 	for_each_fib6_node_rt_rcu(fn) {
2520 		/* prefix routes only use builtin fib6_nh */
2521 		if (rt->nh)
2522 			continue;
2523 
2524 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2525 			continue;
2526 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2527 			continue;
2528 		if ((rt->fib6_flags & flags) != flags)
2529 			continue;
2530 		if ((rt->fib6_flags & noflags) != 0)
2531 			continue;
2532 		if (!fib6_info_hold_safe(rt))
2533 			continue;
2534 		break;
2535 	}
2536 out:
2537 	rcu_read_unlock();
2538 	return rt;
2539 }
2540 
2541 
2542 /* Create "default" multicast route to the interface */
2543 
2544 static void addrconf_add_mroute(struct net_device *dev)
2545 {
2546 	struct fib6_config cfg = {
2547 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2548 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2549 		.fc_ifindex = dev->ifindex,
2550 		.fc_dst_len = 8,
2551 		.fc_flags = RTF_UP,
2552 		.fc_type = RTN_MULTICAST,
2553 		.fc_nlinfo.nl_net = dev_net(dev),
2554 		.fc_protocol = RTPROT_KERNEL,
2555 	};
2556 
2557 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2558 
2559 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2560 }
2561 
2562 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2563 {
2564 	struct inet6_dev *idev;
2565 
2566 	ASSERT_RTNL();
2567 
2568 	idev = ipv6_find_idev(dev);
2569 	if (IS_ERR(idev))
2570 		return idev;
2571 
2572 	if (idev->cnf.disable_ipv6)
2573 		return ERR_PTR(-EACCES);
2574 
2575 	/* Add default multicast route */
2576 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2577 		addrconf_add_mroute(dev);
2578 
2579 	return idev;
2580 }
2581 
2582 static void delete_tempaddrs(struct inet6_dev *idev,
2583 			     struct inet6_ifaddr *ifp)
2584 {
2585 	struct inet6_ifaddr *ift, *tmp;
2586 
2587 	write_lock_bh(&idev->lock);
2588 	list_for_each_entry_safe(ift, tmp, &idev->tempaddr_list, tmp_list) {
2589 		if (ift->ifpub != ifp)
2590 			continue;
2591 
2592 		in6_ifa_hold(ift);
2593 		write_unlock_bh(&idev->lock);
2594 		ipv6_del_addr(ift);
2595 		write_lock_bh(&idev->lock);
2596 	}
2597 	write_unlock_bh(&idev->lock);
2598 }
2599 
2600 static void manage_tempaddrs(struct inet6_dev *idev,
2601 			     struct inet6_ifaddr *ifp,
2602 			     __u32 valid_lft, __u32 prefered_lft,
2603 			     bool create, unsigned long now)
2604 {
2605 	u32 flags;
2606 	struct inet6_ifaddr *ift;
2607 
2608 	read_lock_bh(&idev->lock);
2609 	/* update all temporary addresses in the list */
2610 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2611 		int age, max_valid, max_prefered;
2612 
2613 		if (ifp != ift->ifpub)
2614 			continue;
2615 
2616 		/* RFC 4941 section 3.3:
2617 		 * If a received option will extend the lifetime of a public
2618 		 * address, the lifetimes of temporary addresses should
2619 		 * be extended, subject to the overall constraint that no
2620 		 * temporary addresses should ever remain "valid" or "preferred"
2621 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2622 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2623 		 */
2624 		age = (now - ift->cstamp) / HZ;
2625 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2626 		if (max_valid < 0)
2627 			max_valid = 0;
2628 
2629 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2630 			       idev->desync_factor - age;
2631 		if (max_prefered < 0)
2632 			max_prefered = 0;
2633 
2634 		if (valid_lft > max_valid)
2635 			valid_lft = max_valid;
2636 
2637 		if (prefered_lft > max_prefered)
2638 			prefered_lft = max_prefered;
2639 
2640 		spin_lock(&ift->lock);
2641 		flags = ift->flags;
2642 		ift->valid_lft = valid_lft;
2643 		ift->prefered_lft = prefered_lft;
2644 		ift->tstamp = now;
2645 		if (prefered_lft > 0)
2646 			ift->flags &= ~IFA_F_DEPRECATED;
2647 
2648 		spin_unlock(&ift->lock);
2649 		if (!(flags&IFA_F_TENTATIVE))
2650 			ipv6_ifa_notify(0, ift);
2651 	}
2652 
2653 	/* Also create a temporary address if it's enabled but no temporary
2654 	 * address currently exists.
2655 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2656 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2657 	 * We don't want that to result in creating a new temporary ip address.
2658 	 */
2659 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2660 		create = true;
2661 
2662 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2663 		/* When a new public address is created as described
2664 		 * in [ADDRCONF], also create a new temporary address.
2665 		 */
2666 		read_unlock_bh(&idev->lock);
2667 		ipv6_create_tempaddr(ifp, false);
2668 	} else {
2669 		read_unlock_bh(&idev->lock);
2670 	}
2671 }
2672 
2673 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2674 {
2675 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2676 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2677 }
2678 
2679 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2680 				 const struct prefix_info *pinfo,
2681 				 struct inet6_dev *in6_dev,
2682 				 const struct in6_addr *addr, int addr_type,
2683 				 u32 addr_flags, bool sllao, bool tokenized,
2684 				 __u32 valid_lft, u32 prefered_lft)
2685 {
2686 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2687 	int create = 0, update_lft = 0;
2688 
2689 	if (!ifp && valid_lft) {
2690 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2691 		struct ifa6_config cfg = {
2692 			.pfx = addr,
2693 			.plen = pinfo->prefix_len,
2694 			.ifa_flags = addr_flags,
2695 			.valid_lft = valid_lft,
2696 			.preferred_lft = prefered_lft,
2697 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2698 			.ifa_proto = IFAPROT_KERNEL_RA
2699 		};
2700 
2701 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2702 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2703 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2704 		    !net->ipv6.devconf_all->forwarding && sllao)
2705 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2706 #endif
2707 
2708 		/* Do not allow to create too much of autoconfigured
2709 		 * addresses; this would be too easy way to crash kernel.
2710 		 */
2711 		if (!max_addresses ||
2712 		    ipv6_count_addresses(in6_dev) < max_addresses)
2713 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2714 
2715 		if (IS_ERR_OR_NULL(ifp))
2716 			return -1;
2717 
2718 		create = 1;
2719 		spin_lock_bh(&ifp->lock);
2720 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2721 		ifp->cstamp = jiffies;
2722 		ifp->tokenized = tokenized;
2723 		spin_unlock_bh(&ifp->lock);
2724 		addrconf_dad_start(ifp);
2725 	}
2726 
2727 	if (ifp) {
2728 		u32 flags;
2729 		unsigned long now;
2730 		u32 stored_lft;
2731 
2732 		/* update lifetime (RFC2462 5.5.3 e) */
2733 		spin_lock_bh(&ifp->lock);
2734 		now = jiffies;
2735 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2736 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2737 		else
2738 			stored_lft = 0;
2739 
2740 		/* RFC4862 Section 5.5.3e:
2741 		 * "Note that the preferred lifetime of the
2742 		 *  corresponding address is always reset to
2743 		 *  the Preferred Lifetime in the received
2744 		 *  Prefix Information option, regardless of
2745 		 *  whether the valid lifetime is also reset or
2746 		 *  ignored."
2747 		 *
2748 		 * So we should always update prefered_lft here.
2749 		 */
2750 		update_lft = !create && stored_lft;
2751 
2752 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2753 			const u32 minimum_lft = min_t(u32,
2754 				stored_lft, MIN_VALID_LIFETIME);
2755 			valid_lft = max(valid_lft, minimum_lft);
2756 		}
2757 
2758 		if (update_lft) {
2759 			ifp->valid_lft = valid_lft;
2760 			ifp->prefered_lft = prefered_lft;
2761 			WRITE_ONCE(ifp->tstamp, now);
2762 			flags = ifp->flags;
2763 			ifp->flags &= ~IFA_F_DEPRECATED;
2764 			spin_unlock_bh(&ifp->lock);
2765 
2766 			if (!(flags&IFA_F_TENTATIVE))
2767 				ipv6_ifa_notify(0, ifp);
2768 		} else
2769 			spin_unlock_bh(&ifp->lock);
2770 
2771 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2772 				 create, now);
2773 
2774 		in6_ifa_put(ifp);
2775 		addrconf_verify(net);
2776 	}
2777 
2778 	return 0;
2779 }
2780 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2781 
2782 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2783 {
2784 	struct prefix_info *pinfo;
2785 	struct fib6_table *table;
2786 	__u32 valid_lft;
2787 	__u32 prefered_lft;
2788 	int addr_type, err;
2789 	u32 addr_flags = 0;
2790 	struct inet6_dev *in6_dev;
2791 	struct net *net = dev_net(dev);
2792 	bool ignore_autoconf = false;
2793 
2794 	pinfo = (struct prefix_info *) opt;
2795 
2796 	if (len < sizeof(struct prefix_info)) {
2797 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2798 		return;
2799 	}
2800 
2801 	/*
2802 	 *	Validation checks ([ADDRCONF], page 19)
2803 	 */
2804 
2805 	addr_type = ipv6_addr_type(&pinfo->prefix);
2806 
2807 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2808 		return;
2809 
2810 	valid_lft = ntohl(pinfo->valid);
2811 	prefered_lft = ntohl(pinfo->prefered);
2812 
2813 	if (prefered_lft > valid_lft) {
2814 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2815 		return;
2816 	}
2817 
2818 	in6_dev = in6_dev_get(dev);
2819 
2820 	if (!in6_dev) {
2821 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2822 				    dev->name);
2823 		return;
2824 	}
2825 
2826 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2827 		goto put;
2828 
2829 	/*
2830 	 *	Two things going on here:
2831 	 *	1) Add routes for on-link prefixes
2832 	 *	2) Configure prefixes with the auto flag set
2833 	 */
2834 
2835 	if (pinfo->onlink) {
2836 		struct fib6_info *rt;
2837 		unsigned long rt_expires;
2838 
2839 		/* Avoid arithmetic overflow. Really, we could
2840 		 * save rt_expires in seconds, likely valid_lft,
2841 		 * but it would require division in fib gc, that it
2842 		 * not good.
2843 		 */
2844 		if (HZ > USER_HZ)
2845 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2846 		else
2847 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2848 
2849 		if (addrconf_finite_timeout(rt_expires))
2850 			rt_expires *= HZ;
2851 
2852 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2853 					       pinfo->prefix_len,
2854 					       dev,
2855 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2856 					       RTF_DEFAULT, true);
2857 
2858 		if (rt) {
2859 			/* Autoconf prefix route */
2860 			if (valid_lft == 0) {
2861 				ip6_del_rt(net, rt, false);
2862 				rt = NULL;
2863 			} else {
2864 				table = rt->fib6_table;
2865 				spin_lock_bh(&table->tb6_lock);
2866 
2867 				if (addrconf_finite_timeout(rt_expires)) {
2868 					/* not infinity */
2869 					fib6_set_expires(rt, jiffies + rt_expires);
2870 					fib6_add_gc_list(rt);
2871 				} else {
2872 					fib6_clean_expires(rt);
2873 					fib6_may_remove_gc_list(net, rt);
2874 				}
2875 
2876 				spin_unlock_bh(&table->tb6_lock);
2877 			}
2878 		} else if (valid_lft) {
2879 			clock_t expires = 0;
2880 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2881 			if (addrconf_finite_timeout(rt_expires)) {
2882 				/* not infinity */
2883 				flags |= RTF_EXPIRES;
2884 				expires = jiffies_to_clock_t(rt_expires);
2885 			}
2886 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2887 					      0, dev, expires, flags,
2888 					      GFP_ATOMIC);
2889 		}
2890 		fib6_info_release(rt);
2891 	}
2892 
2893 	/* Try to figure out our local address for this prefix */
2894 
2895 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2896 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2897 		struct in6_addr addr;
2898 		bool tokenized = false, dev_addr_generated = false;
2899 
2900 		if (pinfo->prefix_len == 64) {
2901 			memcpy(&addr, &pinfo->prefix, 8);
2902 
2903 			if (!ipv6_addr_any(&in6_dev->token)) {
2904 				read_lock_bh(&in6_dev->lock);
2905 				memcpy(addr.s6_addr + 8,
2906 				       in6_dev->token.s6_addr + 8, 8);
2907 				read_unlock_bh(&in6_dev->lock);
2908 				tokenized = true;
2909 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2910 				   !ipv6_generate_stable_address(&addr, 0,
2911 								 in6_dev)) {
2912 				addr_flags |= IFA_F_STABLE_PRIVACY;
2913 				goto ok;
2914 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2915 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2916 				goto put;
2917 			} else {
2918 				dev_addr_generated = true;
2919 			}
2920 			goto ok;
2921 		}
2922 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2923 				    pinfo->prefix_len);
2924 		goto put;
2925 
2926 ok:
2927 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2928 						   &addr, addr_type,
2929 						   addr_flags, sllao,
2930 						   tokenized, valid_lft,
2931 						   prefered_lft);
2932 		if (err)
2933 			goto put;
2934 
2935 		/* Ignore error case here because previous prefix add addr was
2936 		 * successful which will be notified.
2937 		 */
2938 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2939 					      addr_type, addr_flags, sllao,
2940 					      tokenized, valid_lft,
2941 					      prefered_lft,
2942 					      dev_addr_generated);
2943 	}
2944 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2945 put:
2946 	in6_dev_put(in6_dev);
2947 }
2948 
2949 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2950 		struct in6_ifreq *ireq)
2951 {
2952 	struct ip_tunnel_parm_kern p = { };
2953 	int err;
2954 
2955 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2956 		return -EADDRNOTAVAIL;
2957 
2958 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2959 	p.iph.version = 4;
2960 	p.iph.ihl = 5;
2961 	p.iph.protocol = IPPROTO_IPV6;
2962 	p.iph.ttl = 64;
2963 
2964 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2965 		return -EOPNOTSUPP;
2966 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2967 	if (err)
2968 		return err;
2969 
2970 	dev = __dev_get_by_name(net, p.name);
2971 	if (!dev)
2972 		return -ENOBUFS;
2973 	return dev_open(dev, NULL);
2974 }
2975 
2976 /*
2977  *	Set destination address.
2978  *	Special case for SIT interfaces where we create a new "virtual"
2979  *	device.
2980  */
2981 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2982 {
2983 	struct net_device *dev;
2984 	struct in6_ifreq ireq;
2985 	int err = -ENODEV;
2986 
2987 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2988 		return -ENODEV;
2989 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2990 		return -EFAULT;
2991 
2992 	rtnl_net_lock(net);
2993 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2994 	if (dev && dev->type == ARPHRD_SIT)
2995 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2996 	rtnl_net_unlock(net);
2997 	return err;
2998 }
2999 
3000 static int ipv6_mc_config(struct sock *sk, bool join,
3001 			  const struct in6_addr *addr, int ifindex)
3002 {
3003 	int ret;
3004 
3005 	ASSERT_RTNL();
3006 
3007 	lock_sock(sk);
3008 	if (join)
3009 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
3010 	else
3011 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
3012 	release_sock(sk);
3013 
3014 	return ret;
3015 }
3016 
3017 /*
3018  *	Manual configuration of address on an interface
3019  */
3020 static int inet6_addr_add(struct net *net, struct net_device *dev,
3021 			  struct ifa6_config *cfg, clock_t expires, u32 flags,
3022 			  struct netlink_ext_ack *extack)
3023 {
3024 	struct inet6_ifaddr *ifp;
3025 	struct inet6_dev *idev;
3026 
3027 	ASSERT_RTNL_NET(net);
3028 
3029 	if (cfg->plen > 128) {
3030 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3031 		return -EINVAL;
3032 	}
3033 
3034 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3035 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3036 		return -EINVAL;
3037 	}
3038 
3039 	idev = addrconf_add_dev(dev);
3040 	if (IS_ERR(idev)) {
3041 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3042 		return PTR_ERR(idev);
3043 	}
3044 
3045 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3046 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3047 					 true, cfg->pfx, dev->ifindex);
3048 
3049 		if (ret < 0) {
3050 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3051 			return ret;
3052 		}
3053 	}
3054 
3055 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3056 
3057 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3058 	if (!IS_ERR(ifp)) {
3059 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3060 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3061 					      ifp->rt_priority, dev, expires,
3062 					      flags, GFP_KERNEL);
3063 		}
3064 
3065 		/* Send a netlink notification if DAD is enabled and
3066 		 * optimistic flag is not set
3067 		 */
3068 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3069 			ipv6_ifa_notify(0, ifp);
3070 		/*
3071 		 * Note that section 3.1 of RFC 4429 indicates
3072 		 * that the Optimistic flag should not be set for
3073 		 * manually configured addresses
3074 		 */
3075 		addrconf_dad_start(ifp);
3076 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3077 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3078 					 cfg->preferred_lft, true, jiffies);
3079 		in6_ifa_put(ifp);
3080 		addrconf_verify_rtnl(net);
3081 		return 0;
3082 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3083 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3084 			       cfg->pfx, dev->ifindex);
3085 	}
3086 
3087 	return PTR_ERR(ifp);
3088 }
3089 
3090 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3091 			  const struct in6_addr *pfx, unsigned int plen,
3092 			  struct netlink_ext_ack *extack)
3093 {
3094 	struct inet6_ifaddr *ifp;
3095 	struct inet6_dev *idev;
3096 	struct net_device *dev;
3097 
3098 	if (plen > 128) {
3099 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3100 		return -EINVAL;
3101 	}
3102 
3103 	dev = __dev_get_by_index(net, ifindex);
3104 	if (!dev) {
3105 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3106 		return -ENODEV;
3107 	}
3108 
3109 	idev = __in6_dev_get_rtnl_net(dev);
3110 	if (!idev) {
3111 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3112 		return -ENXIO;
3113 	}
3114 
3115 	read_lock_bh(&idev->lock);
3116 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3117 		if (ifp->prefix_len == plen &&
3118 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3119 			in6_ifa_hold(ifp);
3120 			read_unlock_bh(&idev->lock);
3121 
3122 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3123 			    (ifp->flags & IFA_F_MANAGETEMPADDR))
3124 				delete_tempaddrs(idev, ifp);
3125 
3126 			ipv6_del_addr(ifp);
3127 
3128 			addrconf_verify_rtnl(net);
3129 			if (ipv6_addr_is_multicast(pfx)) {
3130 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3131 					       false, pfx, dev->ifindex);
3132 			}
3133 			return 0;
3134 		}
3135 	}
3136 	read_unlock_bh(&idev->lock);
3137 
3138 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3139 	return -EADDRNOTAVAIL;
3140 }
3141 
3142 
3143 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3144 {
3145 	struct ifa6_config cfg = {
3146 		.ifa_flags = IFA_F_PERMANENT,
3147 		.preferred_lft = INFINITY_LIFE_TIME,
3148 		.valid_lft = INFINITY_LIFE_TIME,
3149 	};
3150 	struct net_device *dev;
3151 	struct in6_ifreq ireq;
3152 	int err;
3153 
3154 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3155 		return -EPERM;
3156 
3157 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3158 		return -EFAULT;
3159 
3160 	cfg.pfx = &ireq.ifr6_addr;
3161 	cfg.plen = ireq.ifr6_prefixlen;
3162 
3163 	rtnl_net_lock(net);
3164 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3165 	if (dev) {
3166 		netdev_lock_ops(dev);
3167 		err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
3168 		netdev_unlock_ops(dev);
3169 	} else {
3170 		err = -ENODEV;
3171 	}
3172 	rtnl_net_unlock(net);
3173 	return err;
3174 }
3175 
3176 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3177 {
3178 	struct in6_ifreq ireq;
3179 	int err;
3180 
3181 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3182 		return -EPERM;
3183 
3184 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3185 		return -EFAULT;
3186 
3187 	rtnl_net_lock(net);
3188 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3189 			     ireq.ifr6_prefixlen, NULL);
3190 	rtnl_net_unlock(net);
3191 	return err;
3192 }
3193 
3194 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3195 		     int plen, int scope, u8 proto)
3196 {
3197 	struct inet6_ifaddr *ifp;
3198 	struct ifa6_config cfg = {
3199 		.pfx = addr,
3200 		.plen = plen,
3201 		.ifa_flags = IFA_F_PERMANENT,
3202 		.valid_lft = INFINITY_LIFE_TIME,
3203 		.preferred_lft = INFINITY_LIFE_TIME,
3204 		.scope = scope,
3205 		.ifa_proto = proto
3206 	};
3207 
3208 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3209 	if (!IS_ERR(ifp)) {
3210 		spin_lock_bh(&ifp->lock);
3211 		ifp->flags &= ~IFA_F_TENTATIVE;
3212 		spin_unlock_bh(&ifp->lock);
3213 		rt_genid_bump_ipv6(dev_net(idev->dev));
3214 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3215 		in6_ifa_put(ifp);
3216 	}
3217 }
3218 
3219 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE)
3220 static void add_v4_addrs(struct inet6_dev *idev)
3221 {
3222 	struct in6_addr addr;
3223 	struct net_device *dev;
3224 	struct net *net = dev_net(idev->dev);
3225 	int scope, plen;
3226 	u32 pflags = 0;
3227 
3228 	ASSERT_RTNL();
3229 
3230 	memset(&addr, 0, sizeof(struct in6_addr));
3231 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3232 
3233 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3234 		scope = IPV6_ADDR_COMPATv4;
3235 		plen = 96;
3236 		pflags |= RTF_NONEXTHOP;
3237 	} else {
3238 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3239 			return;
3240 
3241 		addr.s6_addr32[0] = htonl(0xfe800000);
3242 		scope = IFA_LINK;
3243 		plen = 64;
3244 	}
3245 
3246 	if (addr.s6_addr32[3]) {
3247 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3248 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3249 				      GFP_KERNEL);
3250 		return;
3251 	}
3252 
3253 	for_each_netdev(net, dev) {
3254 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3255 		if (in_dev && (dev->flags & IFF_UP)) {
3256 			struct in_ifaddr *ifa;
3257 			int flag = scope;
3258 
3259 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3260 				addr.s6_addr32[3] = ifa->ifa_local;
3261 
3262 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3263 					continue;
3264 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3265 					if (idev->dev->flags&IFF_POINTOPOINT)
3266 						continue;
3267 					flag |= IFA_HOST;
3268 				}
3269 
3270 				add_addr(idev, &addr, plen, flag,
3271 					 IFAPROT_UNSPEC);
3272 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3273 						      0, pflags, GFP_KERNEL);
3274 			}
3275 		}
3276 	}
3277 }
3278 #endif
3279 
3280 static void init_loopback(struct net_device *dev)
3281 {
3282 	struct inet6_dev  *idev;
3283 
3284 	/* ::1 */
3285 
3286 	ASSERT_RTNL();
3287 
3288 	idev = ipv6_find_idev(dev);
3289 	if (IS_ERR(idev)) {
3290 		pr_debug("%s: add_dev failed\n", __func__);
3291 		return;
3292 	}
3293 
3294 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3295 }
3296 
3297 void addrconf_add_linklocal(struct inet6_dev *idev,
3298 			    const struct in6_addr *addr, u32 flags)
3299 {
3300 	struct ifa6_config cfg = {
3301 		.pfx = addr,
3302 		.plen = 64,
3303 		.ifa_flags = flags | IFA_F_PERMANENT,
3304 		.valid_lft = INFINITY_LIFE_TIME,
3305 		.preferred_lft = INFINITY_LIFE_TIME,
3306 		.scope = IFA_LINK,
3307 		.ifa_proto = IFAPROT_KERNEL_LL
3308 	};
3309 	struct inet6_ifaddr *ifp;
3310 
3311 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3312 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3313 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3314 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3315 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3316 #endif
3317 
3318 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3319 	if (!IS_ERR(ifp)) {
3320 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3321 				      0, 0, GFP_ATOMIC);
3322 		addrconf_dad_start(ifp);
3323 		in6_ifa_put(ifp);
3324 	}
3325 }
3326 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3327 
3328 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3329 {
3330 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3331 		return true;
3332 
3333 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3334 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3335 		return true;
3336 
3337 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3338 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3339 		return true;
3340 
3341 	return false;
3342 }
3343 
3344 static int ipv6_generate_stable_address(struct in6_addr *address,
3345 					u8 dad_count,
3346 					const struct inet6_dev *idev)
3347 {
3348 	static DEFINE_SPINLOCK(lock);
3349 	static struct sha1_ctx sha_ctx;
3350 
3351 	static union {
3352 		u8 __data[SHA1_BLOCK_SIZE];
3353 		struct {
3354 			struct in6_addr secret;
3355 			__be32 prefix[2];
3356 			unsigned char hwaddr[MAX_ADDR_LEN];
3357 			u8 dad_count;
3358 		} __packed;
3359 	} data;
3360 
3361 	struct in6_addr secret;
3362 	struct in6_addr temp;
3363 	struct net *net = dev_net(idev->dev);
3364 
3365 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3366 
3367 	if (idev->cnf.stable_secret.initialized)
3368 		secret = idev->cnf.stable_secret.secret;
3369 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3370 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3371 	else
3372 		return -1;
3373 
3374 retry:
3375 	spin_lock_bh(&lock);
3376 
3377 	sha1_init(&sha_ctx);
3378 
3379 	memset(&data, 0, sizeof(data));
3380 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3381 	data.prefix[0] = address->s6_addr32[0];
3382 	data.prefix[1] = address->s6_addr32[1];
3383 	data.secret = secret;
3384 	data.dad_count = dad_count;
3385 
3386 	sha1_update(&sha_ctx, data.__data, sizeof(data));
3387 
3388 	/*
3389 	 * Note that the SHA-1 finalization is omitted here, and the digest is
3390 	 * pulled directly from the internal SHA-1 state (making it incompatible
3391 	 * with standard SHA-1).  Unusual, but technically okay since the data
3392 	 * length is fixed and is a multiple of the SHA-1 block size.
3393 	 */
3394 	temp = *address;
3395 	temp.s6_addr32[2] = (__force __be32)sha_ctx.state.h[0];
3396 	temp.s6_addr32[3] = (__force __be32)sha_ctx.state.h[1];
3397 
3398 	spin_unlock_bh(&lock);
3399 
3400 	if (ipv6_reserved_interfaceid(temp)) {
3401 		dad_count++;
3402 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3403 			return -1;
3404 		goto retry;
3405 	}
3406 
3407 	*address = temp;
3408 	return 0;
3409 }
3410 
3411 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3412 {
3413 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3414 
3415 	if (s->initialized)
3416 		return;
3417 	s = &idev->cnf.stable_secret;
3418 	get_random_bytes(&s->secret, sizeof(s->secret));
3419 	s->initialized = true;
3420 }
3421 
3422 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3423 {
3424 	struct in6_addr addr;
3425 
3426 	/* no link local addresses on L3 master devices */
3427 	if (netif_is_l3_master(idev->dev))
3428 		return;
3429 
3430 	/* no link local addresses on devices flagged as slaves */
3431 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3432 		return;
3433 
3434 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3435 
3436 	switch (idev->cnf.addr_gen_mode) {
3437 	case IN6_ADDR_GEN_MODE_RANDOM:
3438 		ipv6_gen_mode_random_init(idev);
3439 		fallthrough;
3440 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3441 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3442 			addrconf_add_linklocal(idev, &addr,
3443 					       IFA_F_STABLE_PRIVACY);
3444 		else if (prefix_route)
3445 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3446 					      0, 0, GFP_KERNEL);
3447 		break;
3448 	case IN6_ADDR_GEN_MODE_EUI64:
3449 		/* addrconf_add_linklocal also adds a prefix_route and we
3450 		 * only need to care about prefix routes if ipv6_generate_eui64
3451 		 * couldn't generate one.
3452 		 */
3453 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3454 			addrconf_add_linklocal(idev, &addr, 0);
3455 		else if (prefix_route)
3456 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3457 					      0, 0, GFP_KERNEL);
3458 		break;
3459 	case IN6_ADDR_GEN_MODE_NONE:
3460 	default:
3461 		/* will not add any link local address */
3462 		break;
3463 	}
3464 }
3465 
3466 static void addrconf_dev_config(struct net_device *dev)
3467 {
3468 	struct inet6_dev *idev;
3469 
3470 	ASSERT_RTNL();
3471 
3472 	if ((dev->type != ARPHRD_ETHER) &&
3473 	    (dev->type != ARPHRD_FDDI) &&
3474 	    (dev->type != ARPHRD_ARCNET) &&
3475 	    (dev->type != ARPHRD_INFINIBAND) &&
3476 	    (dev->type != ARPHRD_IEEE1394) &&
3477 	    (dev->type != ARPHRD_TUNNEL6) &&
3478 	    (dev->type != ARPHRD_6LOWPAN) &&
3479 	    (dev->type != ARPHRD_IP6GRE) &&
3480 	    (dev->type != ARPHRD_TUNNEL) &&
3481 	    (dev->type != ARPHRD_NONE) &&
3482 	    (dev->type != ARPHRD_RAWIP)) {
3483 		/* Alas, we support only Ethernet autoconfiguration. */
3484 		idev = __in6_dev_get(dev);
3485 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3486 		    dev->flags & IFF_MULTICAST)
3487 			ipv6_mc_up(idev);
3488 		return;
3489 	}
3490 
3491 	idev = addrconf_add_dev(dev);
3492 	if (IS_ERR(idev))
3493 		return;
3494 
3495 	/* this device type has no EUI support */
3496 	if (dev->type == ARPHRD_NONE &&
3497 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3498 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3499 			   IN6_ADDR_GEN_MODE_RANDOM);
3500 
3501 	addrconf_addr_gen(idev, false);
3502 }
3503 
3504 #if IS_ENABLED(CONFIG_IPV6_SIT)
3505 static void addrconf_sit_config(struct net_device *dev)
3506 {
3507 	struct inet6_dev *idev;
3508 
3509 	ASSERT_RTNL();
3510 
3511 	/*
3512 	 * Configure the tunnel with one of our IPv4
3513 	 * addresses... we should configure all of
3514 	 * our v4 addrs in the tunnel
3515 	 */
3516 
3517 	idev = ipv6_find_idev(dev);
3518 	if (IS_ERR(idev)) {
3519 		pr_debug("%s: add_dev failed\n", __func__);
3520 		return;
3521 	}
3522 
3523 	if (dev->priv_flags & IFF_ISATAP) {
3524 		addrconf_addr_gen(idev, false);
3525 		return;
3526 	}
3527 
3528 	add_v4_addrs(idev);
3529 
3530 	if (dev->flags&IFF_POINTOPOINT)
3531 		addrconf_add_mroute(dev);
3532 }
3533 #endif
3534 
3535 #if IS_ENABLED(CONFIG_NET_IPGRE)
3536 static void addrconf_gre_config(struct net_device *dev)
3537 {
3538 	struct inet6_dev *idev;
3539 
3540 	ASSERT_RTNL();
3541 
3542 	idev = addrconf_add_dev(dev);
3543 	if (IS_ERR(idev))
3544 		return;
3545 
3546 	/* Generate the IPv6 link-local address using addrconf_addr_gen(),
3547 	 * unless we have an IPv4 GRE device not bound to an IP address and
3548 	 * which is in EUI64 mode (as __ipv6_isatap_ifid() would fail in this
3549 	 * case). Such devices fall back to add_v4_addrs() instead.
3550 	 */
3551 	if (!(*(__be32 *)dev->dev_addr == 0 &&
3552 	      idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)) {
3553 		addrconf_addr_gen(idev, true);
3554 		return;
3555 	}
3556 
3557 	add_v4_addrs(idev);
3558 }
3559 #endif
3560 
3561 static void addrconf_init_auto_addrs(struct net_device *dev)
3562 {
3563 	switch (dev->type) {
3564 #if IS_ENABLED(CONFIG_IPV6_SIT)
3565 	case ARPHRD_SIT:
3566 		addrconf_sit_config(dev);
3567 		break;
3568 #endif
3569 #if IS_ENABLED(CONFIG_NET_IPGRE)
3570 	case ARPHRD_IPGRE:
3571 		addrconf_gre_config(dev);
3572 		break;
3573 #endif
3574 	case ARPHRD_LOOPBACK:
3575 		init_loopback(dev);
3576 		break;
3577 
3578 	default:
3579 		addrconf_dev_config(dev);
3580 		break;
3581 	}
3582 }
3583 
3584 static int fixup_permanent_addr(struct net *net,
3585 				struct inet6_dev *idev,
3586 				struct inet6_ifaddr *ifp)
3587 {
3588 	/* !fib6_node means the host route was removed from the
3589 	 * FIB, for example, if 'lo' device is taken down. In that
3590 	 * case regenerate the host route.
3591 	 */
3592 	if (!ifp->rt || !ifp->rt->fib6_node) {
3593 		struct fib6_info *f6i, *prev;
3594 
3595 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3596 					 GFP_KERNEL, NULL);
3597 		if (IS_ERR(f6i))
3598 			return PTR_ERR(f6i);
3599 
3600 		/* ifp->rt can be accessed outside of rtnl */
3601 		spin_lock_bh(&ifp->lock);
3602 		prev = ifp->rt;
3603 		ifp->rt = f6i;
3604 		spin_unlock_bh(&ifp->lock);
3605 
3606 		fib6_info_release(prev);
3607 	}
3608 
3609 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3610 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3611 				      ifp->rt_priority, idev->dev, 0, 0,
3612 				      GFP_KERNEL);
3613 	}
3614 
3615 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3616 		addrconf_dad_start(ifp);
3617 
3618 	return 0;
3619 }
3620 
3621 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3622 {
3623 	struct inet6_ifaddr *ifp;
3624 	LIST_HEAD(tmp_addr_list);
3625 	struct inet6_dev *idev;
3626 
3627 	/* Mutual exclusion with other if_list_aux users. */
3628 	ASSERT_RTNL();
3629 
3630 	idev = __in6_dev_get(dev);
3631 	if (!idev)
3632 		return;
3633 
3634 	write_lock_bh(&idev->lock);
3635 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3636 		if (ifp->flags & IFA_F_PERMANENT)
3637 			list_add_tail(&ifp->if_list_aux, &tmp_addr_list);
3638 	}
3639 	write_unlock_bh(&idev->lock);
3640 
3641 	while (!list_empty(&tmp_addr_list)) {
3642 		ifp = list_first_entry(&tmp_addr_list,
3643 				       struct inet6_ifaddr, if_list_aux);
3644 		list_del(&ifp->if_list_aux);
3645 
3646 		if (fixup_permanent_addr(net, idev, ifp) < 0) {
3647 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3648 					     idev->dev->name, &ifp->addr);
3649 			in6_ifa_hold(ifp);
3650 			ipv6_del_addr(ifp);
3651 		}
3652 	}
3653 }
3654 
3655 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3656 			   void *ptr)
3657 {
3658 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3659 	struct netdev_notifier_change_info *change_info;
3660 	struct netdev_notifier_changeupper_info *info;
3661 	struct inet6_dev *idev = __in6_dev_get(dev);
3662 	struct net *net = dev_net(dev);
3663 	int run_pending = 0;
3664 	int err;
3665 
3666 	switch (event) {
3667 	case NETDEV_REGISTER:
3668 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3669 			idev = ipv6_add_dev(dev);
3670 			if (IS_ERR(idev))
3671 				return notifier_from_errno(PTR_ERR(idev));
3672 		}
3673 		break;
3674 
3675 	case NETDEV_CHANGEMTU:
3676 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3677 		if (dev->mtu < IPV6_MIN_MTU) {
3678 			addrconf_ifdown(dev, dev != net->loopback_dev);
3679 			break;
3680 		}
3681 
3682 		if (idev) {
3683 			rt6_mtu_change(dev, dev->mtu);
3684 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3685 			break;
3686 		}
3687 
3688 		/* allocate new idev */
3689 		idev = ipv6_add_dev(dev);
3690 		if (IS_ERR(idev))
3691 			break;
3692 
3693 		/* device is still not ready */
3694 		if (!(idev->if_flags & IF_READY))
3695 			break;
3696 
3697 		run_pending = 1;
3698 		fallthrough;
3699 	case NETDEV_UP:
3700 	case NETDEV_CHANGE:
3701 		if (idev && idev->cnf.disable_ipv6)
3702 			break;
3703 
3704 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3705 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3706 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3707 				ipv6_mc_up(idev);
3708 			break;
3709 		}
3710 
3711 		if (event == NETDEV_UP) {
3712 			/* restore routes for permanent addresses */
3713 			addrconf_permanent_addr(net, dev);
3714 
3715 			if (!addrconf_link_ready(dev)) {
3716 				/* device is not ready yet. */
3717 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3718 					 dev->name);
3719 				break;
3720 			}
3721 
3722 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3723 				idev = ipv6_add_dev(dev);
3724 
3725 			if (!IS_ERR_OR_NULL(idev)) {
3726 				idev->if_flags |= IF_READY;
3727 				run_pending = 1;
3728 			}
3729 		} else if (event == NETDEV_CHANGE) {
3730 			if (!addrconf_link_ready(dev)) {
3731 				/* device is still not ready. */
3732 				rt6_sync_down_dev(dev, event);
3733 				break;
3734 			}
3735 
3736 			if (!IS_ERR_OR_NULL(idev)) {
3737 				if (idev->if_flags & IF_READY) {
3738 					/* device is already configured -
3739 					 * but resend MLD reports, we might
3740 					 * have roamed and need to update
3741 					 * multicast snooping switches
3742 					 */
3743 					ipv6_mc_up(idev);
3744 					change_info = ptr;
3745 					if (change_info->flags_changed & IFF_NOARP)
3746 						addrconf_dad_run(idev, true);
3747 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3748 					break;
3749 				}
3750 				idev->if_flags |= IF_READY;
3751 			}
3752 
3753 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3754 				 dev->name);
3755 
3756 			run_pending = 1;
3757 		}
3758 
3759 		addrconf_init_auto_addrs(dev);
3760 
3761 		if (!IS_ERR_OR_NULL(idev)) {
3762 			if (run_pending)
3763 				addrconf_dad_run(idev, false);
3764 
3765 			/* Device has an address by now */
3766 			rt6_sync_up(dev, RTNH_F_DEAD);
3767 
3768 			/*
3769 			 * If the MTU changed during the interface down,
3770 			 * when the interface up, the changed MTU must be
3771 			 * reflected in the idev as well as routers.
3772 			 */
3773 			if (idev->cnf.mtu6 != dev->mtu &&
3774 			    dev->mtu >= IPV6_MIN_MTU) {
3775 				rt6_mtu_change(dev, dev->mtu);
3776 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3777 			}
3778 			WRITE_ONCE(idev->tstamp, jiffies);
3779 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3780 
3781 			/*
3782 			 * If the changed mtu during down is lower than
3783 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3784 			 */
3785 			if (dev->mtu < IPV6_MIN_MTU)
3786 				addrconf_ifdown(dev, dev != net->loopback_dev);
3787 		}
3788 		break;
3789 
3790 	case NETDEV_DOWN:
3791 	case NETDEV_UNREGISTER:
3792 		/*
3793 		 *	Remove all addresses from this interface.
3794 		 */
3795 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3796 		break;
3797 
3798 	case NETDEV_CHANGENAME:
3799 		if (idev) {
3800 			snmp6_unregister_dev(idev);
3801 			addrconf_sysctl_unregister(idev);
3802 			err = addrconf_sysctl_register(idev);
3803 			if (err)
3804 				return notifier_from_errno(err);
3805 			err = snmp6_register_dev(idev);
3806 			if (err) {
3807 				addrconf_sysctl_unregister(idev);
3808 				return notifier_from_errno(err);
3809 			}
3810 		}
3811 		break;
3812 
3813 	case NETDEV_PRE_TYPE_CHANGE:
3814 	case NETDEV_POST_TYPE_CHANGE:
3815 		if (idev)
3816 			addrconf_type_change(dev, event);
3817 		break;
3818 
3819 	case NETDEV_CHANGEUPPER:
3820 		info = ptr;
3821 
3822 		/* flush all routes if dev is linked to or unlinked from
3823 		 * an L3 master device (e.g., VRF)
3824 		 */
3825 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3826 			addrconf_ifdown(dev, false);
3827 	}
3828 
3829 	return NOTIFY_OK;
3830 }
3831 
3832 /*
3833  *	addrconf module should be notified of a device going up
3834  */
3835 static struct notifier_block ipv6_dev_notf = {
3836 	.notifier_call = addrconf_notify,
3837 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3838 };
3839 
3840 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3841 {
3842 	struct inet6_dev *idev;
3843 	ASSERT_RTNL();
3844 
3845 	idev = __in6_dev_get(dev);
3846 
3847 	if (event == NETDEV_POST_TYPE_CHANGE)
3848 		ipv6_mc_remap(idev);
3849 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3850 		ipv6_mc_unmap(idev);
3851 }
3852 
3853 static bool addr_is_local(const struct in6_addr *addr)
3854 {
3855 	return ipv6_addr_type(addr) &
3856 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3857 }
3858 
3859 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3860 {
3861 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3862 	struct net *net = dev_net(dev);
3863 	struct inet6_dev *idev;
3864 	struct inet6_ifaddr *ifa;
3865 	LIST_HEAD(tmp_addr_list);
3866 	bool keep_addr = false;
3867 	bool was_ready;
3868 	int state, i;
3869 
3870 	ASSERT_RTNL();
3871 
3872 	rt6_disable_ip(dev, event);
3873 
3874 	idev = __in6_dev_get(dev);
3875 	if (!idev)
3876 		return -ENODEV;
3877 
3878 	/*
3879 	 * Step 1: remove reference to ipv6 device from parent device.
3880 	 *	   Do not dev_put!
3881 	 */
3882 	if (unregister) {
3883 		WRITE_ONCE(idev->dead, 1);
3884 
3885 		/* protected by rtnl_lock */
3886 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3887 
3888 		/* Step 1.5: remove snmp6 entry */
3889 		snmp6_unregister_dev(idev);
3890 
3891 	}
3892 
3893 	/* combine the user config with event to determine if permanent
3894 	 * addresses are to be removed from address hash table
3895 	 */
3896 	if (!unregister && !idev->cnf.disable_ipv6) {
3897 		/* aggregate the system setting and interface setting */
3898 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3899 
3900 		if (!_keep_addr)
3901 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3902 
3903 		keep_addr = (_keep_addr > 0);
3904 	}
3905 
3906 	/* Step 2: clear hash table */
3907 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3908 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3909 
3910 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3911 restart:
3912 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3913 			if (ifa->idev == idev) {
3914 				addrconf_del_dad_work(ifa);
3915 				/* combined flag + permanent flag decide if
3916 				 * address is retained on a down event
3917 				 */
3918 				if (!keep_addr ||
3919 				    !(ifa->flags & IFA_F_PERMANENT) ||
3920 				    addr_is_local(&ifa->addr)) {
3921 					hlist_del_init_rcu(&ifa->addr_lst);
3922 					goto restart;
3923 				}
3924 			}
3925 		}
3926 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3927 	}
3928 
3929 	write_lock_bh(&idev->lock);
3930 
3931 	addrconf_del_rs_timer(idev);
3932 
3933 	/* Step 2: clear flags for stateless addrconf, repeated down
3934 	 *         detection
3935 	 */
3936 	was_ready = idev->if_flags & IF_READY;
3937 	if (!unregister)
3938 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3939 
3940 	/* Step 3: clear tempaddr list */
3941 	while (!list_empty(&idev->tempaddr_list)) {
3942 		ifa = list_first_entry(&idev->tempaddr_list,
3943 				       struct inet6_ifaddr, tmp_list);
3944 		list_del(&ifa->tmp_list);
3945 		write_unlock_bh(&idev->lock);
3946 		spin_lock_bh(&ifa->lock);
3947 
3948 		if (ifa->ifpub) {
3949 			in6_ifa_put(ifa->ifpub);
3950 			ifa->ifpub = NULL;
3951 		}
3952 		spin_unlock_bh(&ifa->lock);
3953 		in6_ifa_put(ifa);
3954 		write_lock_bh(&idev->lock);
3955 	}
3956 
3957 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3958 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3959 	write_unlock_bh(&idev->lock);
3960 
3961 	while (!list_empty(&tmp_addr_list)) {
3962 		struct fib6_info *rt = NULL;
3963 		bool keep;
3964 
3965 		ifa = list_first_entry(&tmp_addr_list,
3966 				       struct inet6_ifaddr, if_list_aux);
3967 		list_del(&ifa->if_list_aux);
3968 
3969 		addrconf_del_dad_work(ifa);
3970 
3971 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3972 			!addr_is_local(&ifa->addr);
3973 
3974 		spin_lock_bh(&ifa->lock);
3975 
3976 		if (keep) {
3977 			/* set state to skip the notifier below */
3978 			state = INET6_IFADDR_STATE_DEAD;
3979 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3980 			if (!(ifa->flags & IFA_F_NODAD))
3981 				ifa->flags |= IFA_F_TENTATIVE;
3982 
3983 			rt = ifa->rt;
3984 			ifa->rt = NULL;
3985 		} else {
3986 			state = ifa->state;
3987 			ifa->state = INET6_IFADDR_STATE_DEAD;
3988 		}
3989 
3990 		spin_unlock_bh(&ifa->lock);
3991 
3992 		if (rt)
3993 			ip6_del_rt(net, rt, false);
3994 
3995 		if (state != INET6_IFADDR_STATE_DEAD) {
3996 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3997 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3998 		} else {
3999 			if (idev->cnf.forwarding)
4000 				addrconf_leave_anycast(ifa);
4001 			addrconf_leave_solict(ifa->idev, &ifa->addr);
4002 		}
4003 
4004 		if (!keep) {
4005 			write_lock_bh(&idev->lock);
4006 			list_del_rcu(&ifa->if_list);
4007 			write_unlock_bh(&idev->lock);
4008 			in6_ifa_put(ifa);
4009 		}
4010 	}
4011 
4012 	/* Step 5: Discard anycast and multicast list */
4013 	if (unregister) {
4014 		ipv6_ac_destroy_dev(idev);
4015 		ipv6_mc_destroy_dev(idev);
4016 	} else if (was_ready) {
4017 		ipv6_mc_down(idev);
4018 	}
4019 
4020 	WRITE_ONCE(idev->tstamp, jiffies);
4021 	idev->ra_mtu = 0;
4022 
4023 	/* Last: Shot the device (if unregistered) */
4024 	if (unregister) {
4025 		addrconf_sysctl_unregister(idev);
4026 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4027 		neigh_ifdown(&nd_tbl, dev);
4028 		in6_dev_put(idev);
4029 	}
4030 	return 0;
4031 }
4032 
4033 static void addrconf_rs_timer(struct timer_list *t)
4034 {
4035 	struct inet6_dev *idev = timer_container_of(idev, t, rs_timer);
4036 	struct net_device *dev = idev->dev;
4037 	struct in6_addr lladdr;
4038 	int rtr_solicits;
4039 
4040 	write_lock(&idev->lock);
4041 	if (idev->dead || !(idev->if_flags & IF_READY))
4042 		goto out;
4043 
4044 	if (!ipv6_accept_ra(idev))
4045 		goto out;
4046 
4047 	/* Announcement received after solicitation was sent */
4048 	if (idev->if_flags & IF_RA_RCVD)
4049 		goto out;
4050 
4051 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4052 
4053 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4054 		write_unlock(&idev->lock);
4055 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4056 			ndisc_send_rs(dev, &lladdr,
4057 				      &in6addr_linklocal_allrouters);
4058 		else
4059 			goto put;
4060 
4061 		write_lock(&idev->lock);
4062 		idev->rs_interval = rfc3315_s14_backoff_update(
4063 				idev->rs_interval,
4064 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4065 		/* The wait after the last probe can be shorter */
4066 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4067 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4068 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4069 				      idev->rs_interval);
4070 	} else {
4071 		/*
4072 		 * Note: we do not support deprecated "all on-link"
4073 		 * assumption any longer.
4074 		 */
4075 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4076 	}
4077 
4078 out:
4079 	write_unlock(&idev->lock);
4080 put:
4081 	in6_dev_put(idev);
4082 }
4083 
4084 /*
4085  *	Duplicate Address Detection
4086  */
4087 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4088 {
4089 	struct inet6_dev *idev = ifp->idev;
4090 	unsigned long rand_num;
4091 	u64 nonce;
4092 
4093 	if (ifp->flags & IFA_F_OPTIMISTIC)
4094 		rand_num = 0;
4095 	else
4096 		rand_num = get_random_u32_below(
4097 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4098 
4099 	nonce = 0;
4100 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4101 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4102 		do
4103 			get_random_bytes(&nonce, 6);
4104 		while (nonce == 0);
4105 	}
4106 	ifp->dad_nonce = nonce;
4107 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4108 	addrconf_mod_dad_work(ifp, rand_num);
4109 }
4110 
4111 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4112 {
4113 	struct inet6_dev *idev = ifp->idev;
4114 	struct net_device *dev = idev->dev;
4115 	bool bump_id, notify = false;
4116 	struct net *net;
4117 
4118 	addrconf_join_solict(dev, &ifp->addr);
4119 
4120 	read_lock_bh(&idev->lock);
4121 	spin_lock(&ifp->lock);
4122 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4123 		goto out;
4124 
4125 	net = dev_net(dev);
4126 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4127 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4128 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4129 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4130 	    ifp->flags & IFA_F_NODAD) {
4131 		bool send_na = false;
4132 
4133 		if (ifp->flags & IFA_F_TENTATIVE &&
4134 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4135 			send_na = true;
4136 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4137 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4138 		spin_unlock(&ifp->lock);
4139 		read_unlock_bh(&idev->lock);
4140 
4141 		addrconf_dad_completed(ifp, bump_id, send_na);
4142 		return;
4143 	}
4144 
4145 	if (!(idev->if_flags & IF_READY)) {
4146 		spin_unlock(&ifp->lock);
4147 		read_unlock_bh(&idev->lock);
4148 		/*
4149 		 * If the device is not ready:
4150 		 * - keep it tentative if it is a permanent address.
4151 		 * - otherwise, kill it.
4152 		 */
4153 		in6_ifa_hold(ifp);
4154 		addrconf_dad_stop(ifp, 0);
4155 		return;
4156 	}
4157 
4158 	/*
4159 	 * Optimistic nodes can start receiving
4160 	 * Frames right away
4161 	 */
4162 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4163 		ip6_ins_rt(net, ifp->rt);
4164 		if (ipv6_use_optimistic_addr(net, idev)) {
4165 			/* Because optimistic nodes can use this address,
4166 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4167 			 */
4168 			notify = true;
4169 		}
4170 	}
4171 
4172 	addrconf_dad_kick(ifp);
4173 out:
4174 	spin_unlock(&ifp->lock);
4175 	read_unlock_bh(&idev->lock);
4176 	if (notify)
4177 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4178 }
4179 
4180 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4181 {
4182 	bool begin_dad = false;
4183 
4184 	spin_lock_bh(&ifp->lock);
4185 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4186 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4187 		begin_dad = true;
4188 	}
4189 	spin_unlock_bh(&ifp->lock);
4190 
4191 	if (begin_dad)
4192 		addrconf_mod_dad_work(ifp, 0);
4193 }
4194 
4195 static void addrconf_dad_work(struct work_struct *w)
4196 {
4197 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4198 						struct inet6_ifaddr,
4199 						dad_work);
4200 	struct inet6_dev *idev = ifp->idev;
4201 	bool bump_id, disable_ipv6 = false;
4202 	struct in6_addr mcaddr;
4203 	struct net *net;
4204 
4205 	enum {
4206 		DAD_PROCESS,
4207 		DAD_BEGIN,
4208 		DAD_ABORT,
4209 	} action = DAD_PROCESS;
4210 
4211 	net = dev_net(idev->dev);
4212 
4213 	rtnl_net_lock(net);
4214 
4215 	spin_lock_bh(&ifp->lock);
4216 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4217 		action = DAD_BEGIN;
4218 		ifp->state = INET6_IFADDR_STATE_DAD;
4219 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4220 		action = DAD_ABORT;
4221 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4222 
4223 		if ((READ_ONCE(net->ipv6.devconf_all->accept_dad) > 1 ||
4224 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4225 		    !idev->cnf.disable_ipv6 &&
4226 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4227 			struct in6_addr addr;
4228 
4229 			addr.s6_addr32[0] = htonl(0xfe800000);
4230 			addr.s6_addr32[1] = 0;
4231 
4232 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4233 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4234 				/* DAD failed for link-local based on MAC */
4235 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4236 
4237 				pr_info("%s: IPv6 being disabled!\n",
4238 					ifp->idev->dev->name);
4239 				disable_ipv6 = true;
4240 			}
4241 		}
4242 	}
4243 	spin_unlock_bh(&ifp->lock);
4244 
4245 	if (action == DAD_BEGIN) {
4246 		addrconf_dad_begin(ifp);
4247 		goto out;
4248 	} else if (action == DAD_ABORT) {
4249 		in6_ifa_hold(ifp);
4250 		addrconf_dad_stop(ifp, 1);
4251 		if (disable_ipv6)
4252 			addrconf_ifdown(idev->dev, false);
4253 		goto out;
4254 	}
4255 
4256 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4257 		goto out;
4258 
4259 	write_lock_bh(&idev->lock);
4260 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4261 		write_unlock_bh(&idev->lock);
4262 		goto out;
4263 	}
4264 
4265 	spin_lock(&ifp->lock);
4266 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4267 		spin_unlock(&ifp->lock);
4268 		write_unlock_bh(&idev->lock);
4269 		goto out;
4270 	}
4271 
4272 	if (ifp->dad_probes == 0) {
4273 		bool send_na = false;
4274 
4275 		/*
4276 		 * DAD was successful
4277 		 */
4278 
4279 		if (ifp->flags & IFA_F_TENTATIVE &&
4280 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4281 			send_na = true;
4282 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4283 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4284 		spin_unlock(&ifp->lock);
4285 		write_unlock_bh(&idev->lock);
4286 
4287 		addrconf_dad_completed(ifp, bump_id, send_na);
4288 
4289 		goto out;
4290 	}
4291 
4292 	ifp->dad_probes--;
4293 	addrconf_mod_dad_work(ifp,
4294 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4295 				  HZ/100));
4296 	spin_unlock(&ifp->lock);
4297 	write_unlock_bh(&idev->lock);
4298 
4299 	/* send a neighbour solicitation for our addr */
4300 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4301 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4302 		      ifp->dad_nonce);
4303 out:
4304 	in6_ifa_put(ifp);
4305 	rtnl_net_unlock(net);
4306 }
4307 
4308 /* ifp->idev must be at least read locked */
4309 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4310 {
4311 	struct inet6_ifaddr *ifpiter;
4312 	struct inet6_dev *idev = ifp->idev;
4313 
4314 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4315 		if (ifpiter->scope > IFA_LINK)
4316 			break;
4317 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4318 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4319 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4320 		    IFA_F_PERMANENT)
4321 			return false;
4322 	}
4323 	return true;
4324 }
4325 
4326 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4327 				   bool send_na)
4328 {
4329 	struct net_device *dev = ifp->idev->dev;
4330 	struct in6_addr lladdr;
4331 	bool send_rs, send_mld;
4332 
4333 	addrconf_del_dad_work(ifp);
4334 
4335 	/*
4336 	 *	Configure the address for reception. Now it is valid.
4337 	 */
4338 
4339 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4340 
4341 	/* If added prefix is link local and we are prepared to process
4342 	   router advertisements, start sending router solicitations.
4343 	 */
4344 
4345 	read_lock_bh(&ifp->idev->lock);
4346 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4347 	send_rs = send_mld &&
4348 		  ipv6_accept_ra(ifp->idev) &&
4349 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4350 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4351 		  (dev->type != ARPHRD_TUNNEL) &&
4352 		  !netif_is_team_port(dev);
4353 	read_unlock_bh(&ifp->idev->lock);
4354 
4355 	/* While dad is in progress mld report's source address is in6_addrany.
4356 	 * Resend with proper ll now.
4357 	 */
4358 	if (send_mld)
4359 		ipv6_mc_dad_complete(ifp->idev);
4360 
4361 	/* send unsolicited NA if enabled */
4362 	if (send_na &&
4363 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4364 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4365 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4366 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4367 			      /*solicited=*/ false, /*override=*/ true,
4368 			      /*inc_opt=*/ true);
4369 	}
4370 
4371 	if (send_rs) {
4372 		/*
4373 		 *	If a host as already performed a random delay
4374 		 *	[...] as part of DAD [...] there is no need
4375 		 *	to delay again before sending the first RS
4376 		 */
4377 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4378 			return;
4379 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4380 
4381 		write_lock_bh(&ifp->idev->lock);
4382 		spin_lock(&ifp->lock);
4383 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4384 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4385 		ifp->idev->rs_probes = 1;
4386 		ifp->idev->if_flags |= IF_RS_SENT;
4387 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4388 		spin_unlock(&ifp->lock);
4389 		write_unlock_bh(&ifp->idev->lock);
4390 	}
4391 
4392 	if (bump_id)
4393 		rt_genid_bump_ipv6(dev_net(dev));
4394 
4395 	/* Make sure that a new temporary address will be created
4396 	 * before this temporary address becomes deprecated.
4397 	 */
4398 	if (ifp->flags & IFA_F_TEMPORARY)
4399 		addrconf_verify_rtnl(dev_net(dev));
4400 }
4401 
4402 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4403 {
4404 	struct inet6_ifaddr *ifp;
4405 
4406 	read_lock_bh(&idev->lock);
4407 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4408 		spin_lock(&ifp->lock);
4409 		if ((ifp->flags & IFA_F_TENTATIVE &&
4410 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4411 			if (restart)
4412 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4413 			addrconf_dad_kick(ifp);
4414 		}
4415 		spin_unlock(&ifp->lock);
4416 	}
4417 	read_unlock_bh(&idev->lock);
4418 }
4419 
4420 #ifdef CONFIG_PROC_FS
4421 struct if6_iter_state {
4422 	struct seq_net_private p;
4423 	int bucket;
4424 	int offset;
4425 };
4426 
4427 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4428 {
4429 	struct if6_iter_state *state = seq->private;
4430 	struct net *net = seq_file_net(seq);
4431 	struct inet6_ifaddr *ifa = NULL;
4432 	int p = 0;
4433 
4434 	/* initial bucket if pos is 0 */
4435 	if (pos == 0) {
4436 		state->bucket = 0;
4437 		state->offset = 0;
4438 	}
4439 
4440 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4441 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4442 					 addr_lst) {
4443 			/* sync with offset */
4444 			if (p < state->offset) {
4445 				p++;
4446 				continue;
4447 			}
4448 			return ifa;
4449 		}
4450 
4451 		/* prepare for next bucket */
4452 		state->offset = 0;
4453 		p = 0;
4454 	}
4455 	return NULL;
4456 }
4457 
4458 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4459 					 struct inet6_ifaddr *ifa)
4460 {
4461 	struct if6_iter_state *state = seq->private;
4462 	struct net *net = seq_file_net(seq);
4463 
4464 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4465 		state->offset++;
4466 		return ifa;
4467 	}
4468 
4469 	state->offset = 0;
4470 	while (++state->bucket < IN6_ADDR_HSIZE) {
4471 		hlist_for_each_entry_rcu(ifa,
4472 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4473 			return ifa;
4474 		}
4475 	}
4476 
4477 	return NULL;
4478 }
4479 
4480 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4481 	__acquires(rcu)
4482 {
4483 	rcu_read_lock();
4484 	return if6_get_first(seq, *pos);
4485 }
4486 
4487 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4488 {
4489 	struct inet6_ifaddr *ifa;
4490 
4491 	ifa = if6_get_next(seq, v);
4492 	++*pos;
4493 	return ifa;
4494 }
4495 
4496 static void if6_seq_stop(struct seq_file *seq, void *v)
4497 	__releases(rcu)
4498 {
4499 	rcu_read_unlock();
4500 }
4501 
4502 static int if6_seq_show(struct seq_file *seq, void *v)
4503 {
4504 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4505 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4506 		   &ifp->addr,
4507 		   ifp->idev->dev->ifindex,
4508 		   ifp->prefix_len,
4509 		   ifp->scope,
4510 		   (u8) ifp->flags,
4511 		   ifp->idev->dev->name);
4512 	return 0;
4513 }
4514 
4515 static const struct seq_operations if6_seq_ops = {
4516 	.start	= if6_seq_start,
4517 	.next	= if6_seq_next,
4518 	.show	= if6_seq_show,
4519 	.stop	= if6_seq_stop,
4520 };
4521 
4522 static int __net_init if6_proc_net_init(struct net *net)
4523 {
4524 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4525 			sizeof(struct if6_iter_state)))
4526 		return -ENOMEM;
4527 	return 0;
4528 }
4529 
4530 static void __net_exit if6_proc_net_exit(struct net *net)
4531 {
4532 	remove_proc_entry("if_inet6", net->proc_net);
4533 }
4534 
4535 static struct pernet_operations if6_proc_net_ops = {
4536 	.init = if6_proc_net_init,
4537 	.exit = if6_proc_net_exit,
4538 };
4539 
4540 int __init if6_proc_init(void)
4541 {
4542 	return register_pernet_subsys(&if6_proc_net_ops);
4543 }
4544 
4545 void if6_proc_exit(void)
4546 {
4547 	unregister_pernet_subsys(&if6_proc_net_ops);
4548 }
4549 #endif	/* CONFIG_PROC_FS */
4550 
4551 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4552 /* Check if address is a home address configured on any interface. */
4553 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4554 {
4555 	unsigned int hash = inet6_addr_hash(net, addr);
4556 	struct inet6_ifaddr *ifp = NULL;
4557 	int ret = 0;
4558 
4559 	rcu_read_lock();
4560 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4561 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4562 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4563 			ret = 1;
4564 			break;
4565 		}
4566 	}
4567 	rcu_read_unlock();
4568 	return ret;
4569 }
4570 #endif
4571 
4572 /* RFC6554 has some algorithm to avoid loops in segment routing by
4573  * checking if the segments contains any of a local interface address.
4574  *
4575  * Quote:
4576  *
4577  * To detect loops in the SRH, a router MUST determine if the SRH
4578  * includes multiple addresses assigned to any interface on that router.
4579  * If such addresses appear more than once and are separated by at least
4580  * one address not assigned to that router.
4581  */
4582 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4583 			  unsigned char nsegs)
4584 {
4585 	const struct in6_addr *addr;
4586 	int i, ret = 0, found = 0;
4587 	struct inet6_ifaddr *ifp;
4588 	bool separated = false;
4589 	unsigned int hash;
4590 	bool hash_found;
4591 
4592 	rcu_read_lock();
4593 	for (i = 0; i < nsegs; i++) {
4594 		addr = &segs[i];
4595 		hash = inet6_addr_hash(net, addr);
4596 
4597 		hash_found = false;
4598 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4599 
4600 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4601 				hash_found = true;
4602 				break;
4603 			}
4604 		}
4605 
4606 		if (hash_found) {
4607 			if (found > 1 && separated) {
4608 				ret = 1;
4609 				break;
4610 			}
4611 
4612 			separated = false;
4613 			found++;
4614 		} else {
4615 			separated = true;
4616 		}
4617 	}
4618 	rcu_read_unlock();
4619 
4620 	return ret;
4621 }
4622 
4623 /*
4624  *	Periodic address status verification
4625  */
4626 
4627 static void addrconf_verify_rtnl(struct net *net)
4628 {
4629 	unsigned long now, next, next_sec, next_sched;
4630 	struct inet6_ifaddr *ifp;
4631 	int i;
4632 
4633 	ASSERT_RTNL();
4634 
4635 	rcu_read_lock_bh();
4636 	now = jiffies;
4637 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4638 
4639 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4640 
4641 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4642 restart:
4643 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4644 			unsigned long age;
4645 
4646 			/* When setting preferred_lft to a value not zero or
4647 			 * infinity, while valid_lft is infinity
4648 			 * IFA_F_PERMANENT has a non-infinity life time.
4649 			 */
4650 			if ((ifp->flags & IFA_F_PERMANENT) &&
4651 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4652 				continue;
4653 
4654 			spin_lock(&ifp->lock);
4655 			/* We try to batch several events at once. */
4656 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4657 
4658 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4659 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4660 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4661 			    !ifp->regen_count && ifp->ifpub) {
4662 				/* This is a non-regenerated temporary addr. */
4663 
4664 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4665 
4666 				if (age + regen_advance >= ifp->prefered_lft) {
4667 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4668 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4669 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4670 
4671 					ifp->regen_count++;
4672 					in6_ifa_hold(ifp);
4673 					in6_ifa_hold(ifpub);
4674 					spin_unlock(&ifp->lock);
4675 
4676 					spin_lock(&ifpub->lock);
4677 					ifpub->regen_count = 0;
4678 					spin_unlock(&ifpub->lock);
4679 					rcu_read_unlock_bh();
4680 					ipv6_create_tempaddr(ifpub, true);
4681 					in6_ifa_put(ifpub);
4682 					in6_ifa_put(ifp);
4683 					rcu_read_lock_bh();
4684 					goto restart;
4685 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4686 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4687 			}
4688 
4689 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4690 			    age >= ifp->valid_lft) {
4691 				spin_unlock(&ifp->lock);
4692 				in6_ifa_hold(ifp);
4693 				rcu_read_unlock_bh();
4694 				ipv6_del_addr(ifp);
4695 				rcu_read_lock_bh();
4696 				goto restart;
4697 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4698 				spin_unlock(&ifp->lock);
4699 				continue;
4700 			} else if (age >= ifp->prefered_lft) {
4701 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4702 				int deprecate = 0;
4703 
4704 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4705 					deprecate = 1;
4706 					ifp->flags |= IFA_F_DEPRECATED;
4707 				}
4708 
4709 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4710 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4711 					next = ifp->tstamp + ifp->valid_lft * HZ;
4712 
4713 				spin_unlock(&ifp->lock);
4714 
4715 				if (deprecate) {
4716 					in6_ifa_hold(ifp);
4717 
4718 					ipv6_ifa_notify(0, ifp);
4719 					in6_ifa_put(ifp);
4720 					goto restart;
4721 				}
4722 			} else {
4723 				/* ifp->prefered_lft <= ifp->valid_lft */
4724 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4725 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4726 				spin_unlock(&ifp->lock);
4727 			}
4728 		}
4729 	}
4730 
4731 	next_sec = round_jiffies_up(next);
4732 	next_sched = next;
4733 
4734 	/* If rounded timeout is accurate enough, accept it. */
4735 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4736 		next_sched = next_sec;
4737 
4738 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4739 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4740 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4741 
4742 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4743 		 now, next, next_sec, next_sched);
4744 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4745 	rcu_read_unlock_bh();
4746 }
4747 
4748 static void addrconf_verify_work(struct work_struct *w)
4749 {
4750 	struct net *net = container_of(to_delayed_work(w), struct net,
4751 				       ipv6.addr_chk_work);
4752 
4753 	rtnl_net_lock(net);
4754 	addrconf_verify_rtnl(net);
4755 	rtnl_net_unlock(net);
4756 }
4757 
4758 static void addrconf_verify(struct net *net)
4759 {
4760 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4761 }
4762 
4763 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4764 				     struct in6_addr **peer_pfx)
4765 {
4766 	struct in6_addr *pfx = NULL;
4767 
4768 	*peer_pfx = NULL;
4769 
4770 	if (addr)
4771 		pfx = nla_data(addr);
4772 
4773 	if (local) {
4774 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4775 			*peer_pfx = pfx;
4776 		pfx = nla_data(local);
4777 	}
4778 
4779 	return pfx;
4780 }
4781 
4782 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4783 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4784 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4785 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4786 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4787 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4788 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4789 	[IFA_PROTO]		= { .type = NLA_U8 },
4790 };
4791 
4792 static int
4793 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4794 		  struct netlink_ext_ack *extack)
4795 {
4796 	struct net *net = sock_net(skb->sk);
4797 	struct ifaddrmsg *ifm;
4798 	struct nlattr *tb[IFA_MAX+1];
4799 	struct in6_addr *pfx, *peer_pfx;
4800 	u32 ifa_flags;
4801 	int err;
4802 
4803 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4804 				     ifa_ipv6_policy, extack);
4805 	if (err < 0)
4806 		return err;
4807 
4808 	ifm = nlmsg_data(nlh);
4809 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4810 	if (!pfx)
4811 		return -EINVAL;
4812 
4813 	ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4814 
4815 	/* We ignore other flags so far. */
4816 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4817 
4818 	rtnl_net_lock(net);
4819 	err = inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4820 			     ifm->ifa_prefixlen, extack);
4821 	rtnl_net_unlock(net);
4822 
4823 	return err;
4824 }
4825 
4826 static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp,
4827 			       unsigned long expires, u32 flags,
4828 			       bool modify_peer)
4829 {
4830 	struct fib6_table *table;
4831 	struct fib6_info *f6i;
4832 	u32 prio;
4833 
4834 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4835 					ifp->prefix_len,
4836 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4837 	if (!f6i)
4838 		return -ENOENT;
4839 
4840 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4841 	if (f6i->fib6_metric != prio) {
4842 		/* delete old one */
4843 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4844 
4845 		/* add new one */
4846 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4847 				      ifp->prefix_len,
4848 				      ifp->rt_priority, ifp->idev->dev,
4849 				      expires, flags, GFP_KERNEL);
4850 		return 0;
4851 	}
4852 	if (f6i != net->ipv6.fib6_null_entry) {
4853 		table = f6i->fib6_table;
4854 		spin_lock_bh(&table->tb6_lock);
4855 
4856 		if (!(flags & RTF_EXPIRES)) {
4857 			fib6_clean_expires(f6i);
4858 			fib6_may_remove_gc_list(net, f6i);
4859 		} else {
4860 			fib6_set_expires(f6i, expires);
4861 			fib6_add_gc_list(f6i);
4862 		}
4863 
4864 		spin_unlock_bh(&table->tb6_lock);
4865 	}
4866 	fib6_info_release(f6i);
4867 
4868 	return 0;
4869 }
4870 
4871 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4872 			     struct ifa6_config *cfg, clock_t expires,
4873 			     u32 flags)
4874 {
4875 	bool was_managetempaddr;
4876 	bool new_peer = false;
4877 	bool had_prefixroute;
4878 
4879 	ASSERT_RTNL_NET(net);
4880 
4881 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4882 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4883 		return -EINVAL;
4884 
4885 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4886 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4887 
4888 	if (cfg->peer_pfx &&
4889 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4890 		if (!ipv6_addr_any(&ifp->peer_addr))
4891 			cleanup_prefix_route(ifp, expires, true, true);
4892 		new_peer = true;
4893 	}
4894 
4895 	spin_lock_bh(&ifp->lock);
4896 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4897 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4898 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4899 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4900 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4901 			IFA_F_NOPREFIXROUTE);
4902 	ifp->flags |= cfg->ifa_flags;
4903 	WRITE_ONCE(ifp->tstamp, jiffies);
4904 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4905 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4906 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4907 
4908 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4909 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4910 
4911 	if (new_peer)
4912 		ifp->peer_addr = *cfg->peer_pfx;
4913 
4914 	spin_unlock_bh(&ifp->lock);
4915 	if (!(ifp->flags&IFA_F_TENTATIVE))
4916 		ipv6_ifa_notify(0, ifp);
4917 
4918 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4919 		int rc = -ENOENT;
4920 
4921 		if (had_prefixroute)
4922 			rc = modify_prefix_route(net, ifp, expires, flags, false);
4923 
4924 		/* prefix route could have been deleted; if so restore it */
4925 		if (rc == -ENOENT) {
4926 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4927 					      ifp->rt_priority, ifp->idev->dev,
4928 					      expires, flags, GFP_KERNEL);
4929 		}
4930 
4931 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4932 			rc = modify_prefix_route(net, ifp, expires, flags, true);
4933 
4934 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4935 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4936 					      ifp->rt_priority, ifp->idev->dev,
4937 					      expires, flags, GFP_KERNEL);
4938 		}
4939 	} else if (had_prefixroute) {
4940 		enum cleanup_prefix_rt_t action;
4941 		unsigned long rt_expires;
4942 
4943 		write_lock_bh(&ifp->idev->lock);
4944 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4945 		write_unlock_bh(&ifp->idev->lock);
4946 
4947 		if (action != CLEANUP_PREFIX_RT_NOP) {
4948 			cleanup_prefix_route(ifp, rt_expires,
4949 				action == CLEANUP_PREFIX_RT_DEL, false);
4950 		}
4951 	}
4952 
4953 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4954 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4955 			delete_tempaddrs(ifp->idev, ifp);
4956 		else
4957 			manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4958 					 cfg->preferred_lft, !was_managetempaddr,
4959 					 jiffies);
4960 	}
4961 
4962 	addrconf_verify_rtnl(net);
4963 
4964 	return 0;
4965 }
4966 
4967 static int
4968 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4969 		  struct netlink_ext_ack *extack)
4970 {
4971 	struct net *net = sock_net(skb->sk);
4972 	struct nlattr *tb[IFA_MAX+1];
4973 	struct in6_addr *peer_pfx;
4974 	struct inet6_ifaddr *ifa;
4975 	struct net_device *dev;
4976 	struct inet6_dev *idev;
4977 	struct ifa6_config cfg;
4978 	struct ifaddrmsg *ifm;
4979 	unsigned long timeout;
4980 	clock_t expires;
4981 	u32 flags;
4982 	int err;
4983 
4984 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4985 				     ifa_ipv6_policy, extack);
4986 	if (err < 0)
4987 		return err;
4988 
4989 	memset(&cfg, 0, sizeof(cfg));
4990 
4991 	ifm = nlmsg_data(nlh);
4992 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4993 	if (!cfg.pfx)
4994 		return -EINVAL;
4995 
4996 	cfg.peer_pfx = peer_pfx;
4997 	cfg.plen = ifm->ifa_prefixlen;
4998 	if (tb[IFA_RT_PRIORITY])
4999 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
5000 
5001 	if (tb[IFA_PROTO])
5002 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
5003 
5004 	cfg.ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
5005 
5006 	/* We ignore other flags so far. */
5007 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
5008 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
5009 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
5010 
5011 	cfg.ifa_flags |= IFA_F_PERMANENT;
5012 	cfg.valid_lft = INFINITY_LIFE_TIME;
5013 	cfg.preferred_lft = INFINITY_LIFE_TIME;
5014 	expires = 0;
5015 	flags = 0;
5016 
5017 	if (tb[IFA_CACHEINFO]) {
5018 		struct ifa_cacheinfo *ci;
5019 
5020 		ci = nla_data(tb[IFA_CACHEINFO]);
5021 		cfg.valid_lft = ci->ifa_valid;
5022 		cfg.preferred_lft = ci->ifa_prefered;
5023 
5024 		if (!cfg.valid_lft || cfg.preferred_lft > cfg.valid_lft) {
5025 			NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
5026 			return -EINVAL;
5027 		}
5028 
5029 		timeout = addrconf_timeout_fixup(cfg.valid_lft, HZ);
5030 		if (addrconf_finite_timeout(timeout)) {
5031 			cfg.ifa_flags &= ~IFA_F_PERMANENT;
5032 			cfg.valid_lft = timeout;
5033 			expires = jiffies_to_clock_t(timeout * HZ);
5034 			flags = RTF_EXPIRES;
5035 		}
5036 
5037 		timeout = addrconf_timeout_fixup(cfg.preferred_lft, HZ);
5038 		if (addrconf_finite_timeout(timeout)) {
5039 			if (timeout == 0)
5040 				cfg.ifa_flags |= IFA_F_DEPRECATED;
5041 
5042 			cfg.preferred_lft = timeout;
5043 		}
5044 	}
5045 
5046 	rtnl_net_lock(net);
5047 
5048 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5049 	if (!dev) {
5050 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5051 		err = -ENODEV;
5052 		goto unlock_rtnl;
5053 	}
5054 
5055 	netdev_lock_ops(dev);
5056 	idev = ipv6_find_idev(dev);
5057 	if (IS_ERR(idev)) {
5058 		err = PTR_ERR(idev);
5059 		goto unlock;
5060 	}
5061 
5062 	if (!ipv6_allow_optimistic_dad(net, idev))
5063 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5064 
5065 	if (cfg.ifa_flags & IFA_F_NODAD &&
5066 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5067 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5068 		err = -EINVAL;
5069 		goto unlock;
5070 	}
5071 
5072 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5073 	if (!ifa) {
5074 		/*
5075 		 * It would be best to check for !NLM_F_CREATE here but
5076 		 * userspace already relies on not having to provide this.
5077 		 */
5078 		err = inet6_addr_add(net, dev, &cfg, expires, flags, extack);
5079 		goto unlock;
5080 	}
5081 
5082 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5083 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5084 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5085 		err = -EEXIST;
5086 	} else {
5087 		err = inet6_addr_modify(net, ifa, &cfg, expires, flags);
5088 	}
5089 
5090 	in6_ifa_put(ifa);
5091 unlock:
5092 	netdev_unlock_ops(dev);
5093 unlock_rtnl:
5094 	rtnl_net_unlock(net);
5095 
5096 	return err;
5097 }
5098 
5099 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5100 			  u8 scope, int ifindex)
5101 {
5102 	struct ifaddrmsg *ifm;
5103 
5104 	ifm = nlmsg_data(nlh);
5105 	ifm->ifa_family = AF_INET6;
5106 	ifm->ifa_prefixlen = prefixlen;
5107 	ifm->ifa_flags = flags;
5108 	ifm->ifa_scope = scope;
5109 	ifm->ifa_index = ifindex;
5110 }
5111 
5112 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5113 			 unsigned long tstamp, u32 preferred, u32 valid)
5114 {
5115 	struct ifa_cacheinfo ci;
5116 
5117 	ci.cstamp = cstamp_delta(cstamp);
5118 	ci.tstamp = cstamp_delta(tstamp);
5119 	ci.ifa_prefered = preferred;
5120 	ci.ifa_valid = valid;
5121 
5122 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5123 }
5124 
5125 static inline int rt_scope(int ifa_scope)
5126 {
5127 	if (ifa_scope & IFA_HOST)
5128 		return RT_SCOPE_HOST;
5129 	else if (ifa_scope & IFA_LINK)
5130 		return RT_SCOPE_LINK;
5131 	else if (ifa_scope & IFA_SITE)
5132 		return RT_SCOPE_SITE;
5133 	else
5134 		return RT_SCOPE_UNIVERSE;
5135 }
5136 
5137 static inline int inet6_ifaddr_msgsize(void)
5138 {
5139 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5140 	       + nla_total_size(16) /* IFA_LOCAL */
5141 	       + nla_total_size(16) /* IFA_ADDRESS */
5142 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5143 	       + nla_total_size(4)  /* IFA_FLAGS */
5144 	       + nla_total_size(1)  /* IFA_PROTO */
5145 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5146 }
5147 
5148 static int inet6_fill_ifaddr(struct sk_buff *skb,
5149 			     const struct inet6_ifaddr *ifa,
5150 			     struct inet6_fill_args *args)
5151 {
5152 	struct nlmsghdr *nlh;
5153 	u32 preferred, valid;
5154 	u32 flags, priority;
5155 	u8 proto;
5156 
5157 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5158 			sizeof(struct ifaddrmsg), args->flags);
5159 	if (!nlh)
5160 		return -EMSGSIZE;
5161 
5162 	flags = READ_ONCE(ifa->flags);
5163 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5164 		      ifa->idev->dev->ifindex);
5165 
5166 	if (args->netnsid >= 0 &&
5167 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5168 		goto error;
5169 
5170 	preferred = READ_ONCE(ifa->prefered_lft);
5171 	valid = READ_ONCE(ifa->valid_lft);
5172 
5173 	if (!((flags & IFA_F_PERMANENT) &&
5174 	      (preferred == INFINITY_LIFE_TIME))) {
5175 		if (preferred != INFINITY_LIFE_TIME) {
5176 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5177 
5178 			if (preferred > tval)
5179 				preferred -= tval;
5180 			else
5181 				preferred = 0;
5182 			if (valid != INFINITY_LIFE_TIME) {
5183 				if (valid > tval)
5184 					valid -= tval;
5185 				else
5186 					valid = 0;
5187 			}
5188 		}
5189 	} else {
5190 		preferred = INFINITY_LIFE_TIME;
5191 		valid = INFINITY_LIFE_TIME;
5192 	}
5193 
5194 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5195 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5196 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5197 			goto error;
5198 	} else {
5199 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5200 			goto error;
5201 	}
5202 
5203 	priority = READ_ONCE(ifa->rt_priority);
5204 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5205 		goto error;
5206 
5207 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5208 			  preferred, valid) < 0)
5209 		goto error;
5210 
5211 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5212 		goto error;
5213 
5214 	proto = READ_ONCE(ifa->ifa_proto);
5215 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5216 		goto error;
5217 
5218 	nlmsg_end(skb, nlh);
5219 	return 0;
5220 
5221 error:
5222 	nlmsg_cancel(skb, nlh);
5223 	return -EMSGSIZE;
5224 }
5225 
5226 int inet6_fill_ifmcaddr(struct sk_buff *skb,
5227 			const struct ifmcaddr6 *ifmca,
5228 			struct inet6_fill_args *args)
5229 {
5230 	int ifindex = ifmca->idev->dev->ifindex;
5231 	u8 scope = RT_SCOPE_UNIVERSE;
5232 	struct nlmsghdr *nlh;
5233 
5234 	if (!args->force_rt_scope_universe &&
5235 	    ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5236 		scope = RT_SCOPE_SITE;
5237 
5238 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5239 			sizeof(struct ifaddrmsg), args->flags);
5240 	if (!nlh)
5241 		return -EMSGSIZE;
5242 
5243 	if (args->netnsid >= 0 &&
5244 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5245 		nlmsg_cancel(skb, nlh);
5246 		return -EMSGSIZE;
5247 	}
5248 
5249 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5250 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5251 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5252 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5253 		nlmsg_cancel(skb, nlh);
5254 		return -EMSGSIZE;
5255 	}
5256 
5257 	nlmsg_end(skb, nlh);
5258 	return 0;
5259 }
5260 
5261 int inet6_fill_ifacaddr(struct sk_buff *skb,
5262 			const struct ifacaddr6 *ifaca,
5263 			struct inet6_fill_args *args)
5264 {
5265 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5266 	int ifindex = dev ? dev->ifindex : 1;
5267 	u8 scope = RT_SCOPE_UNIVERSE;
5268 	struct nlmsghdr *nlh;
5269 
5270 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5271 		scope = RT_SCOPE_SITE;
5272 
5273 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5274 			sizeof(struct ifaddrmsg), args->flags);
5275 	if (!nlh)
5276 		return -EMSGSIZE;
5277 
5278 	if (args->netnsid >= 0 &&
5279 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5280 		nlmsg_cancel(skb, nlh);
5281 		return -EMSGSIZE;
5282 	}
5283 
5284 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5285 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5286 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5287 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5288 		nlmsg_cancel(skb, nlh);
5289 		return -EMSGSIZE;
5290 	}
5291 
5292 	nlmsg_end(skb, nlh);
5293 	return 0;
5294 }
5295 
5296 /* called with rcu_read_lock() */
5297 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5298 			  struct netlink_callback *cb, int *s_ip_idx,
5299 			  struct inet6_fill_args *fillargs)
5300 {
5301 	const struct ifmcaddr6 *ifmca;
5302 	const struct ifacaddr6 *ifaca;
5303 	int ip_idx = 0;
5304 	int err = 0;
5305 
5306 	switch (fillargs->type) {
5307 	case UNICAST_ADDR: {
5308 		const struct inet6_ifaddr *ifa;
5309 		fillargs->event = RTM_NEWADDR;
5310 
5311 		/* unicast address incl. temp addr */
5312 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5313 			if (ip_idx < *s_ip_idx)
5314 				goto next;
5315 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5316 			if (err < 0)
5317 				break;
5318 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5319 next:
5320 			ip_idx++;
5321 		}
5322 		break;
5323 	}
5324 	case MULTICAST_ADDR:
5325 		fillargs->event = RTM_GETMULTICAST;
5326 
5327 		/* multicast address */
5328 		for (ifmca = rcu_dereference(idev->mc_list);
5329 		     ifmca;
5330 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5331 			if (ip_idx < *s_ip_idx)
5332 				continue;
5333 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5334 			if (err < 0)
5335 				break;
5336 		}
5337 		break;
5338 	case ANYCAST_ADDR:
5339 		fillargs->event = RTM_GETANYCAST;
5340 		/* anycast address */
5341 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5342 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5343 			if (ip_idx < *s_ip_idx)
5344 				continue;
5345 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5346 			if (err < 0)
5347 				break;
5348 		}
5349 		break;
5350 	default:
5351 		break;
5352 	}
5353 	*s_ip_idx = err ? ip_idx : 0;
5354 	return err;
5355 }
5356 
5357 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5358 				       struct inet6_fill_args *fillargs,
5359 				       struct net **tgt_net, struct sock *sk,
5360 				       struct netlink_callback *cb)
5361 {
5362 	struct netlink_ext_ack *extack = cb->extack;
5363 	struct nlattr *tb[IFA_MAX+1];
5364 	struct ifaddrmsg *ifm;
5365 	int err, i;
5366 
5367 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5368 	if (!ifm) {
5369 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5370 		return -EINVAL;
5371 	}
5372 
5373 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5374 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5375 		return -EINVAL;
5376 	}
5377 
5378 	fillargs->ifindex = ifm->ifa_index;
5379 	if (fillargs->ifindex) {
5380 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5381 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5382 	}
5383 
5384 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5385 					    ifa_ipv6_policy, extack);
5386 	if (err < 0)
5387 		return err;
5388 
5389 	for (i = 0; i <= IFA_MAX; ++i) {
5390 		if (!tb[i])
5391 			continue;
5392 
5393 		if (i == IFA_TARGET_NETNSID) {
5394 			struct net *net;
5395 
5396 			fillargs->netnsid = nla_get_s32(tb[i]);
5397 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5398 			if (IS_ERR(net)) {
5399 				fillargs->netnsid = -1;
5400 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5401 				return PTR_ERR(net);
5402 			}
5403 			*tgt_net = net;
5404 		} else {
5405 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5406 			return -EINVAL;
5407 		}
5408 	}
5409 
5410 	return 0;
5411 }
5412 
5413 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5414 			   enum addr_type_t type)
5415 {
5416 	struct net *tgt_net = sock_net(skb->sk);
5417 	const struct nlmsghdr *nlh = cb->nlh;
5418 	struct inet6_fill_args fillargs = {
5419 		.portid = NETLINK_CB(cb->skb).portid,
5420 		.seq = cb->nlh->nlmsg_seq,
5421 		.flags = NLM_F_MULTI,
5422 		.netnsid = -1,
5423 		.type = type,
5424 		.force_rt_scope_universe = false,
5425 	};
5426 	struct {
5427 		unsigned long ifindex;
5428 		int ip_idx;
5429 	} *ctx = (void *)cb->ctx;
5430 	struct net_device *dev;
5431 	struct inet6_dev *idev;
5432 	int err = 0;
5433 
5434 	rcu_read_lock();
5435 	if (cb->strict_check) {
5436 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5437 						  skb->sk, cb);
5438 		if (err < 0)
5439 			goto done;
5440 
5441 		err = 0;
5442 		if (fillargs.ifindex) {
5443 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5444 			if (!dev) {
5445 				err = -ENODEV;
5446 				goto done;
5447 			}
5448 			idev = __in6_dev_get(dev);
5449 			if (idev)
5450 				err = in6_dump_addrs(idev, skb, cb,
5451 						     &ctx->ip_idx,
5452 						     &fillargs);
5453 			goto done;
5454 		}
5455 	}
5456 
5457 	cb->seq = inet6_base_seq(tgt_net);
5458 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5459 		idev = __in6_dev_get(dev);
5460 		if (!idev)
5461 			continue;
5462 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5463 				     &fillargs);
5464 		if (err < 0)
5465 			goto done;
5466 	}
5467 done:
5468 	rcu_read_unlock();
5469 	if (fillargs.netnsid >= 0)
5470 		put_net(tgt_net);
5471 
5472 	return err;
5473 }
5474 
5475 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5476 {
5477 	enum addr_type_t type = UNICAST_ADDR;
5478 
5479 	return inet6_dump_addr(skb, cb, type);
5480 }
5481 
5482 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5483 {
5484 	enum addr_type_t type = MULTICAST_ADDR;
5485 
5486 	return inet6_dump_addr(skb, cb, type);
5487 }
5488 
5489 
5490 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5491 {
5492 	enum addr_type_t type = ANYCAST_ADDR;
5493 
5494 	return inet6_dump_addr(skb, cb, type);
5495 }
5496 
5497 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5498 				       const struct nlmsghdr *nlh,
5499 				       struct nlattr **tb,
5500 				       struct netlink_ext_ack *extack)
5501 {
5502 	struct ifaddrmsg *ifm;
5503 	int i, err;
5504 
5505 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5506 	if (!ifm) {
5507 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5508 		return -EINVAL;
5509 	}
5510 
5511 	if (!netlink_strict_get_check(skb))
5512 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5513 					      ifa_ipv6_policy, extack);
5514 
5515 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5516 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5517 		return -EINVAL;
5518 	}
5519 
5520 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5521 					    ifa_ipv6_policy, extack);
5522 	if (err)
5523 		return err;
5524 
5525 	for (i = 0; i <= IFA_MAX; i++) {
5526 		if (!tb[i])
5527 			continue;
5528 
5529 		switch (i) {
5530 		case IFA_TARGET_NETNSID:
5531 		case IFA_ADDRESS:
5532 		case IFA_LOCAL:
5533 			break;
5534 		default:
5535 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5536 			return -EINVAL;
5537 		}
5538 	}
5539 
5540 	return 0;
5541 }
5542 
5543 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5544 			     struct netlink_ext_ack *extack)
5545 {
5546 	struct net *tgt_net = sock_net(in_skb->sk);
5547 	struct inet6_fill_args fillargs = {
5548 		.portid = NETLINK_CB(in_skb).portid,
5549 		.seq = nlh->nlmsg_seq,
5550 		.event = RTM_NEWADDR,
5551 		.flags = 0,
5552 		.netnsid = -1,
5553 		.force_rt_scope_universe = false,
5554 	};
5555 	struct ifaddrmsg *ifm;
5556 	struct nlattr *tb[IFA_MAX+1];
5557 	struct in6_addr *addr = NULL, *peer;
5558 	struct net_device *dev = NULL;
5559 	struct inet6_ifaddr *ifa;
5560 	struct sk_buff *skb;
5561 	int err;
5562 
5563 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5564 	if (err < 0)
5565 		return err;
5566 
5567 	if (tb[IFA_TARGET_NETNSID]) {
5568 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5569 
5570 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5571 						  fillargs.netnsid);
5572 		if (IS_ERR(tgt_net))
5573 			return PTR_ERR(tgt_net);
5574 	}
5575 
5576 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5577 	if (!addr) {
5578 		err = -EINVAL;
5579 		goto errout;
5580 	}
5581 	ifm = nlmsg_data(nlh);
5582 	if (ifm->ifa_index)
5583 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5584 
5585 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5586 	if (!ifa) {
5587 		err = -EADDRNOTAVAIL;
5588 		goto errout;
5589 	}
5590 
5591 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5592 	if (!skb) {
5593 		err = -ENOBUFS;
5594 		goto errout_ifa;
5595 	}
5596 
5597 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5598 	if (err < 0) {
5599 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5600 		WARN_ON(err == -EMSGSIZE);
5601 		kfree_skb(skb);
5602 		goto errout_ifa;
5603 	}
5604 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5605 errout_ifa:
5606 	in6_ifa_put(ifa);
5607 errout:
5608 	dev_put(dev);
5609 	if (fillargs.netnsid >= 0)
5610 		put_net(tgt_net);
5611 
5612 	return err;
5613 }
5614 
5615 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5616 {
5617 	struct sk_buff *skb;
5618 	struct net *net = dev_net(ifa->idev->dev);
5619 	struct inet6_fill_args fillargs = {
5620 		.portid = 0,
5621 		.seq = 0,
5622 		.event = event,
5623 		.flags = 0,
5624 		.netnsid = -1,
5625 		.force_rt_scope_universe = false,
5626 	};
5627 	int err = -ENOBUFS;
5628 
5629 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5630 	if (!skb)
5631 		goto errout;
5632 
5633 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5634 	if (err < 0) {
5635 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5636 		WARN_ON(err == -EMSGSIZE);
5637 		kfree_skb(skb);
5638 		goto errout;
5639 	}
5640 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5641 	return;
5642 errout:
5643 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5644 }
5645 
5646 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5647 			       __s32 *array, int bytes)
5648 {
5649 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5650 
5651 	memset(array, 0, bytes);
5652 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5653 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5654 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5655 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5656 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5657 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5658 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5659 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5660 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5661 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5662 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5663 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5664 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5665 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5666 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5667 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5668 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5669 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5670 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5671 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5672 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5673 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5674 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5675 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5676 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5677 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5678 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5679 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5680 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5681 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5682 #ifdef CONFIG_IPV6_ROUTER_PREF
5683 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5684 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5685 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5686 #ifdef CONFIG_IPV6_ROUTE_INFO
5687 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5688 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5689 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5690 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5691 #endif
5692 #endif
5693 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5694 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5695 		READ_ONCE(cnf->accept_source_route);
5696 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5697 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5698 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5699 #endif
5700 #ifdef CONFIG_IPV6_MROUTE
5701 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5702 #endif
5703 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5704 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5705 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5706 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5707 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5708 		READ_ONCE(cnf->suppress_frag_ndisc);
5709 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5710 		READ_ONCE(cnf->accept_ra_from_local);
5711 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5712 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5713 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5714 	/* we omit DEVCONF_STABLE_SECRET for now */
5715 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5716 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5717 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5718 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5719 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5720 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5721 #ifdef CONFIG_IPV6_SEG6_HMAC
5722 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5723 #endif
5724 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5725 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5726 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5727 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5728 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5729 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5730 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5731 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5732 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5733 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5734 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5735 		READ_ONCE(cnf->accept_untracked_na);
5736 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5737 	array[DEVCONF_FORCE_FORWARDING] = READ_ONCE(cnf->force_forwarding);
5738 }
5739 
5740 static inline size_t inet6_ifla6_size(void)
5741 {
5742 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5743 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5744 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5745 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5746 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5747 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5748 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5749 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5750 	     + 0;
5751 }
5752 
5753 static inline size_t inet6_if_nlmsg_size(void)
5754 {
5755 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5756 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5757 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5758 	       + nla_total_size(4) /* IFLA_MTU */
5759 	       + nla_total_size(4) /* IFLA_LINK */
5760 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5761 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5762 }
5763 
5764 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5765 					int bytes)
5766 {
5767 	int i;
5768 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5769 	BUG_ON(pad < 0);
5770 
5771 	/* Use put_unaligned() because stats may not be aligned for u64. */
5772 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5773 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5774 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5775 
5776 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5777 }
5778 
5779 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5780 					int bytes, size_t syncpoff)
5781 {
5782 	int i, c;
5783 	u64 buff[IPSTATS_MIB_MAX];
5784 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5785 
5786 	BUG_ON(pad < 0);
5787 
5788 	memset(buff, 0, sizeof(buff));
5789 	buff[0] = IPSTATS_MIB_MAX;
5790 
5791 	for_each_possible_cpu(c) {
5792 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5793 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5794 	}
5795 
5796 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5797 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5798 }
5799 
5800 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5801 			     int bytes)
5802 {
5803 	switch (attrtype) {
5804 	case IFLA_INET6_STATS:
5805 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5806 				     offsetof(struct ipstats_mib, syncp));
5807 		break;
5808 	case IFLA_INET6_ICMP6STATS:
5809 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5810 		break;
5811 	}
5812 }
5813 
5814 static int inet6_fill_ifla6_stats_attrs(struct sk_buff *skb,
5815 					struct inet6_dev *idev)
5816 {
5817 	struct nlattr *nla;
5818 
5819 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5820 	if (!nla)
5821 		goto nla_put_failure;
5822 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5823 
5824 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5825 	if (!nla)
5826 		goto nla_put_failure;
5827 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5828 
5829 	return 0;
5830 
5831 nla_put_failure:
5832 	return -EMSGSIZE;
5833 }
5834 
5835 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5836 				  u32 ext_filter_mask)
5837 {
5838 	struct ifla_cacheinfo ci;
5839 	struct nlattr *nla;
5840 	u32 ra_mtu;
5841 
5842 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5843 		goto nla_put_failure;
5844 	ci.max_reasm_len = IPV6_MAXPLEN;
5845 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5846 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5847 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5848 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5849 		goto nla_put_failure;
5850 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5851 	if (!nla)
5852 		goto nla_put_failure;
5853 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5854 
5855 	/* XXX - MC not implemented */
5856 
5857 	if (!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS)) {
5858 		if (inet6_fill_ifla6_stats_attrs(skb, idev) < 0)
5859 			goto nla_put_failure;
5860 	}
5861 
5862 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5863 	if (!nla)
5864 		goto nla_put_failure;
5865 	read_lock_bh(&idev->lock);
5866 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5867 	read_unlock_bh(&idev->lock);
5868 
5869 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5870 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5871 		goto nla_put_failure;
5872 
5873 	ra_mtu = READ_ONCE(idev->ra_mtu);
5874 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5875 		goto nla_put_failure;
5876 
5877 	return 0;
5878 
5879 nla_put_failure:
5880 	return -EMSGSIZE;
5881 }
5882 
5883 static size_t inet6_get_link_af_size(const struct net_device *dev,
5884 				     u32 ext_filter_mask)
5885 {
5886 	if (!__in6_dev_get(dev))
5887 		return 0;
5888 
5889 	return inet6_ifla6_size();
5890 }
5891 
5892 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5893 			      u32 ext_filter_mask)
5894 {
5895 	struct inet6_dev *idev = __in6_dev_get(dev);
5896 
5897 	if (!idev)
5898 		return -ENODATA;
5899 
5900 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5901 		return -EMSGSIZE;
5902 
5903 	return 0;
5904 }
5905 
5906 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5907 			     struct netlink_ext_ack *extack)
5908 {
5909 	struct inet6_ifaddr *ifp;
5910 	struct net_device *dev = idev->dev;
5911 	bool clear_token, update_rs = false;
5912 	struct in6_addr ll_addr;
5913 
5914 	ASSERT_RTNL();
5915 
5916 	if (!token)
5917 		return -EINVAL;
5918 
5919 	if (dev->flags & IFF_LOOPBACK) {
5920 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5921 		return -EINVAL;
5922 	}
5923 
5924 	if (dev->flags & IFF_NOARP) {
5925 		NL_SET_ERR_MSG_MOD(extack,
5926 				   "Device does not do neighbour discovery");
5927 		return -EINVAL;
5928 	}
5929 
5930 	if (!ipv6_accept_ra(idev)) {
5931 		NL_SET_ERR_MSG_MOD(extack,
5932 				   "Router advertisement is disabled on device");
5933 		return -EINVAL;
5934 	}
5935 
5936 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5937 		NL_SET_ERR_MSG(extack,
5938 			       "Router solicitation is disabled on device");
5939 		return -EINVAL;
5940 	}
5941 
5942 	write_lock_bh(&idev->lock);
5943 
5944 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5945 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5946 
5947 	write_unlock_bh(&idev->lock);
5948 
5949 	clear_token = ipv6_addr_any(token);
5950 	if (clear_token)
5951 		goto update_lft;
5952 
5953 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5954 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5955 			     IFA_F_OPTIMISTIC)) {
5956 		/* If we're not ready, then normal ifup will take care
5957 		 * of this. Otherwise, we need to request our rs here.
5958 		 */
5959 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5960 		update_rs = true;
5961 	}
5962 
5963 update_lft:
5964 	write_lock_bh(&idev->lock);
5965 
5966 	if (update_rs) {
5967 		idev->if_flags |= IF_RS_SENT;
5968 		idev->rs_interval = rfc3315_s14_backoff_init(
5969 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5970 		idev->rs_probes = 1;
5971 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5972 	}
5973 
5974 	/* Well, that's kinda nasty ... */
5975 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5976 		spin_lock(&ifp->lock);
5977 		if (ifp->tokenized) {
5978 			ifp->valid_lft = 0;
5979 			ifp->prefered_lft = 0;
5980 		}
5981 		spin_unlock(&ifp->lock);
5982 	}
5983 
5984 	write_unlock_bh(&idev->lock);
5985 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5986 	addrconf_verify_rtnl(dev_net(dev));
5987 	return 0;
5988 }
5989 
5990 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5991 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5992 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5993 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5994 					    .reject_message =
5995 						"IFLA_INET6_RA_MTU can not be set" },
5996 };
5997 
5998 static int check_addr_gen_mode(int mode)
5999 {
6000 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
6001 	    mode != IN6_ADDR_GEN_MODE_NONE &&
6002 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
6003 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
6004 		return -EINVAL;
6005 	return 1;
6006 }
6007 
6008 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
6009 				int mode)
6010 {
6011 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
6012 	    !idev->cnf.stable_secret.initialized &&
6013 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
6014 		return -EINVAL;
6015 	return 1;
6016 }
6017 
6018 static int inet6_validate_link_af(const struct net_device *dev,
6019 				  const struct nlattr *nla,
6020 				  struct netlink_ext_ack *extack)
6021 {
6022 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6023 	struct inet6_dev *idev = NULL;
6024 	int err;
6025 
6026 	if (dev) {
6027 		idev = __in6_dev_get(dev);
6028 		if (!idev)
6029 			return -EAFNOSUPPORT;
6030 	}
6031 
6032 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
6033 					  inet6_af_policy, extack);
6034 	if (err)
6035 		return err;
6036 
6037 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6038 		return -EINVAL;
6039 
6040 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6041 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6042 
6043 		if (check_addr_gen_mode(mode) < 0)
6044 			return -EINVAL;
6045 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6046 			return -EINVAL;
6047 	}
6048 
6049 	return 0;
6050 }
6051 
6052 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6053 			     struct netlink_ext_ack *extack)
6054 {
6055 	struct inet6_dev *idev = __in6_dev_get(dev);
6056 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6057 	int err;
6058 
6059 	if (!idev)
6060 		return -EAFNOSUPPORT;
6061 
6062 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6063 		return -EINVAL;
6064 
6065 	if (tb[IFLA_INET6_TOKEN]) {
6066 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6067 					extack);
6068 		if (err)
6069 			return err;
6070 	}
6071 
6072 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6073 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6074 
6075 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6076 	}
6077 
6078 	return 0;
6079 }
6080 
6081 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6082 			     u32 portid, u32 seq, int event, unsigned int flags)
6083 {
6084 	struct net_device *dev = idev->dev;
6085 	struct ifinfomsg *hdr;
6086 	struct nlmsghdr *nlh;
6087 	int ifindex, iflink;
6088 	void *protoinfo;
6089 
6090 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6091 	if (!nlh)
6092 		return -EMSGSIZE;
6093 
6094 	hdr = nlmsg_data(nlh);
6095 	hdr->ifi_family = AF_INET6;
6096 	hdr->__ifi_pad = 0;
6097 	hdr->ifi_type = dev->type;
6098 	ifindex = READ_ONCE(dev->ifindex);
6099 	hdr->ifi_index = ifindex;
6100 	hdr->ifi_flags = netif_get_flags(dev);
6101 	hdr->ifi_change = 0;
6102 
6103 	iflink = dev_get_iflink(dev);
6104 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6105 	    (dev->addr_len &&
6106 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6107 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6108 	    (ifindex != iflink &&
6109 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6110 	    nla_put_u8(skb, IFLA_OPERSTATE,
6111 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6112 		goto nla_put_failure;
6113 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6114 	if (!protoinfo)
6115 		goto nla_put_failure;
6116 
6117 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6118 		goto nla_put_failure;
6119 
6120 	nla_nest_end(skb, protoinfo);
6121 	nlmsg_end(skb, nlh);
6122 	return 0;
6123 
6124 nla_put_failure:
6125 	nlmsg_cancel(skb, nlh);
6126 	return -EMSGSIZE;
6127 }
6128 
6129 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6130 				   struct netlink_ext_ack *extack)
6131 {
6132 	struct ifinfomsg *ifm;
6133 
6134 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
6135 	if (!ifm) {
6136 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6137 		return -EINVAL;
6138 	}
6139 
6140 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6141 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6142 		return -EINVAL;
6143 	}
6144 
6145 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6146 	    ifm->ifi_change || ifm->ifi_index) {
6147 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6148 		return -EINVAL;
6149 	}
6150 
6151 	return 0;
6152 }
6153 
6154 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6155 {
6156 	struct net *net = sock_net(skb->sk);
6157 	struct {
6158 		unsigned long ifindex;
6159 	} *ctx = (void *)cb->ctx;
6160 	struct net_device *dev;
6161 	struct inet6_dev *idev;
6162 	int err;
6163 
6164 	/* only requests using strict checking can pass data to
6165 	 * influence the dump
6166 	 */
6167 	if (cb->strict_check) {
6168 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6169 
6170 		if (err < 0)
6171 			return err;
6172 	}
6173 
6174 	err = 0;
6175 	rcu_read_lock();
6176 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6177 		idev = __in6_dev_get(dev);
6178 		if (!idev)
6179 			continue;
6180 		err = inet6_fill_ifinfo(skb, idev,
6181 					NETLINK_CB(cb->skb).portid,
6182 					cb->nlh->nlmsg_seq,
6183 					RTM_NEWLINK, NLM_F_MULTI);
6184 		if (err < 0)
6185 			break;
6186 	}
6187 	rcu_read_unlock();
6188 
6189 	return err;
6190 }
6191 
6192 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6193 {
6194 	struct sk_buff *skb;
6195 	struct net *net = dev_net(idev->dev);
6196 	int err = -ENOBUFS;
6197 
6198 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6199 	if (!skb)
6200 		goto errout;
6201 
6202 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6203 	if (err < 0) {
6204 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6205 		WARN_ON(err == -EMSGSIZE);
6206 		kfree_skb(skb);
6207 		goto errout;
6208 	}
6209 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6210 	return;
6211 errout:
6212 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6213 }
6214 
6215 static inline size_t inet6_prefix_nlmsg_size(void)
6216 {
6217 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6218 	       + nla_total_size(sizeof(struct in6_addr))
6219 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6220 }
6221 
6222 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6223 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6224 			     int event, unsigned int flags)
6225 {
6226 	struct prefixmsg *pmsg;
6227 	struct nlmsghdr *nlh;
6228 	struct prefix_cacheinfo	ci;
6229 
6230 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6231 	if (!nlh)
6232 		return -EMSGSIZE;
6233 
6234 	pmsg = nlmsg_data(nlh);
6235 	pmsg->prefix_family = AF_INET6;
6236 	pmsg->prefix_pad1 = 0;
6237 	pmsg->prefix_pad2 = 0;
6238 	pmsg->prefix_ifindex = idev->dev->ifindex;
6239 	pmsg->prefix_len = pinfo->prefix_len;
6240 	pmsg->prefix_type = pinfo->type;
6241 	pmsg->prefix_pad3 = 0;
6242 	pmsg->prefix_flags = pinfo->flags;
6243 
6244 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6245 		goto nla_put_failure;
6246 	ci.preferred_time = ntohl(pinfo->prefered);
6247 	ci.valid_time = ntohl(pinfo->valid);
6248 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6249 		goto nla_put_failure;
6250 	nlmsg_end(skb, nlh);
6251 	return 0;
6252 
6253 nla_put_failure:
6254 	nlmsg_cancel(skb, nlh);
6255 	return -EMSGSIZE;
6256 }
6257 
6258 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6259 			 struct prefix_info *pinfo)
6260 {
6261 	struct sk_buff *skb;
6262 	struct net *net = dev_net(idev->dev);
6263 	int err = -ENOBUFS;
6264 
6265 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6266 	if (!skb)
6267 		goto errout;
6268 
6269 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6270 	if (err < 0) {
6271 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6272 		WARN_ON(err == -EMSGSIZE);
6273 		kfree_skb(skb);
6274 		goto errout;
6275 	}
6276 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6277 	return;
6278 errout:
6279 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6280 }
6281 
6282 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6283 {
6284 	struct net *net = dev_net(ifp->idev->dev);
6285 
6286 	if (event)
6287 		ASSERT_RTNL();
6288 
6289 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6290 
6291 	switch (event) {
6292 	case RTM_NEWADDR:
6293 		/*
6294 		 * If the address was optimistic we inserted the route at the
6295 		 * start of our DAD process, so we don't need to do it again.
6296 		 * If the device was taken down in the middle of the DAD
6297 		 * cycle there is a race where we could get here without a
6298 		 * host route, so nothing to insert. That will be fixed when
6299 		 * the device is brought up.
6300 		 */
6301 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6302 			ip6_ins_rt(net, ifp->rt);
6303 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6304 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6305 				&ifp->addr, ifp->idev->dev->name);
6306 		}
6307 
6308 		if (ifp->idev->cnf.forwarding)
6309 			addrconf_join_anycast(ifp);
6310 		if (!ipv6_addr_any(&ifp->peer_addr))
6311 			addrconf_prefix_route(&ifp->peer_addr, 128,
6312 					      ifp->rt_priority, ifp->idev->dev,
6313 					      0, 0, GFP_ATOMIC);
6314 		break;
6315 	case RTM_DELADDR:
6316 		if (ifp->idev->cnf.forwarding)
6317 			addrconf_leave_anycast(ifp);
6318 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6319 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6320 			struct fib6_info *rt;
6321 
6322 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6323 						       ifp->idev->dev, 0, 0,
6324 						       false);
6325 			if (rt)
6326 				ip6_del_rt(net, rt, false);
6327 		}
6328 		if (ifp->rt) {
6329 			ip6_del_rt(net, ifp->rt, false);
6330 			ifp->rt = NULL;
6331 		}
6332 		rt_genid_bump_ipv6(net);
6333 		break;
6334 	}
6335 	atomic_inc(&net->ipv6.dev_addr_genid);
6336 }
6337 
6338 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6339 {
6340 	if (likely(ifp->idev->dead == 0))
6341 		__ipv6_ifa_notify(event, ifp);
6342 }
6343 
6344 #ifdef CONFIG_SYSCTL
6345 
6346 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6347 		void *buffer, size_t *lenp, loff_t *ppos)
6348 {
6349 	int *valp = ctl->data;
6350 	int val = *valp;
6351 	loff_t pos = *ppos;
6352 	struct ctl_table lctl;
6353 	int ret;
6354 
6355 	/*
6356 	 * ctl->data points to idev->cnf.forwarding, we should
6357 	 * not modify it until we get the rtnl lock.
6358 	 */
6359 	lctl = *ctl;
6360 	lctl.data = &val;
6361 
6362 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6363 
6364 	if (write)
6365 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6366 	if (ret)
6367 		*ppos = pos;
6368 	return ret;
6369 }
6370 
6371 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6372 		void *buffer, size_t *lenp, loff_t *ppos)
6373 {
6374 	struct inet6_dev *idev = ctl->extra1;
6375 	int min_mtu = IPV6_MIN_MTU;
6376 	struct ctl_table lctl;
6377 
6378 	lctl = *ctl;
6379 	lctl.extra1 = &min_mtu;
6380 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6381 
6382 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6383 }
6384 
6385 static void dev_disable_change(struct inet6_dev *idev)
6386 {
6387 	struct netdev_notifier_info info;
6388 
6389 	if (!idev || !idev->dev)
6390 		return;
6391 
6392 	netdev_notifier_info_init(&info, idev->dev);
6393 	if (idev->cnf.disable_ipv6)
6394 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6395 	else
6396 		addrconf_notify(NULL, NETDEV_UP, &info);
6397 }
6398 
6399 static void addrconf_disable_change(struct net *net, __s32 newf)
6400 {
6401 	struct net_device *dev;
6402 	struct inet6_dev *idev;
6403 
6404 	for_each_netdev(net, dev) {
6405 		idev = __in6_dev_get_rtnl_net(dev);
6406 		if (idev) {
6407 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6408 
6409 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6410 			if (changed)
6411 				dev_disable_change(idev);
6412 		}
6413 	}
6414 }
6415 
6416 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6417 {
6418 	struct net *net = (struct net *)table->extra2;
6419 	int old;
6420 
6421 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6422 		WRITE_ONCE(*p, newf);
6423 		return 0;
6424 	}
6425 
6426 	if (!rtnl_net_trylock(net))
6427 		return restart_syscall();
6428 
6429 	old = *p;
6430 	WRITE_ONCE(*p, newf);
6431 
6432 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6433 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6434 		addrconf_disable_change(net, newf);
6435 	} else if ((!newf) ^ (!old)) {
6436 		dev_disable_change((struct inet6_dev *)table->extra1);
6437 	}
6438 
6439 	rtnl_net_unlock(net);
6440 	return 0;
6441 }
6442 
6443 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6444 		void *buffer, size_t *lenp, loff_t *ppos)
6445 {
6446 	int *valp = ctl->data;
6447 	int val = *valp;
6448 	loff_t pos = *ppos;
6449 	struct ctl_table lctl;
6450 	int ret;
6451 
6452 	/*
6453 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6454 	 * not modify it until we get the rtnl lock.
6455 	 */
6456 	lctl = *ctl;
6457 	lctl.data = &val;
6458 
6459 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6460 
6461 	if (write)
6462 		ret = addrconf_disable_ipv6(ctl, valp, val);
6463 	if (ret)
6464 		*ppos = pos;
6465 	return ret;
6466 }
6467 
6468 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6469 		void *buffer, size_t *lenp, loff_t *ppos)
6470 {
6471 	int *valp = ctl->data;
6472 	int ret;
6473 	int old, new;
6474 
6475 	old = *valp;
6476 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6477 	new = *valp;
6478 
6479 	if (write && old != new) {
6480 		struct net *net = ctl->extra2;
6481 
6482 		if (!rtnl_net_trylock(net))
6483 			return restart_syscall();
6484 
6485 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp) {
6486 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6487 						     NETCONFA_PROXY_NEIGH,
6488 						     NETCONFA_IFINDEX_DEFAULT,
6489 						     net->ipv6.devconf_dflt);
6490 		} else if (valp == &net->ipv6.devconf_all->proxy_ndp) {
6491 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6492 						     NETCONFA_PROXY_NEIGH,
6493 						     NETCONFA_IFINDEX_ALL,
6494 						     net->ipv6.devconf_all);
6495 		} else {
6496 			struct inet6_dev *idev = ctl->extra1;
6497 
6498 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6499 						     NETCONFA_PROXY_NEIGH,
6500 						     idev->dev->ifindex,
6501 						     &idev->cnf);
6502 		}
6503 		rtnl_net_unlock(net);
6504 	}
6505 
6506 	return ret;
6507 }
6508 
6509 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6510 					 void *buffer, size_t *lenp,
6511 					 loff_t *ppos)
6512 {
6513 	int ret = 0;
6514 	u32 new_val;
6515 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6516 	struct net *net = (struct net *)ctl->extra2;
6517 	struct ctl_table tmp = {
6518 		.data = &new_val,
6519 		.maxlen = sizeof(new_val),
6520 		.mode = ctl->mode,
6521 	};
6522 
6523 	if (!rtnl_net_trylock(net))
6524 		return restart_syscall();
6525 
6526 	new_val = *((u32 *)ctl->data);
6527 
6528 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6529 	if (ret != 0)
6530 		goto out;
6531 
6532 	if (write) {
6533 		if (check_addr_gen_mode(new_val) < 0) {
6534 			ret = -EINVAL;
6535 			goto out;
6536 		}
6537 
6538 		if (idev) {
6539 			if (check_stable_privacy(idev, net, new_val) < 0) {
6540 				ret = -EINVAL;
6541 				goto out;
6542 			}
6543 
6544 			if (idev->cnf.addr_gen_mode != new_val) {
6545 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6546 				netdev_lock_ops(idev->dev);
6547 				addrconf_init_auto_addrs(idev->dev);
6548 				netdev_unlock_ops(idev->dev);
6549 			}
6550 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6551 			struct net_device *dev;
6552 
6553 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6554 			for_each_netdev(net, dev) {
6555 				idev = __in6_dev_get_rtnl_net(dev);
6556 				if (idev &&
6557 				    idev->cnf.addr_gen_mode != new_val) {
6558 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6559 						  new_val);
6560 					netdev_lock_ops(idev->dev);
6561 					addrconf_init_auto_addrs(idev->dev);
6562 					netdev_unlock_ops(idev->dev);
6563 				}
6564 			}
6565 		}
6566 
6567 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6568 	}
6569 
6570 out:
6571 	rtnl_net_unlock(net);
6572 
6573 	return ret;
6574 }
6575 
6576 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6577 					 void *buffer, size_t *lenp,
6578 					 loff_t *ppos)
6579 {
6580 	int err;
6581 	struct in6_addr addr;
6582 	char str[IPV6_MAX_STRLEN];
6583 	struct ctl_table lctl = *ctl;
6584 	struct net *net = ctl->extra2;
6585 	struct ipv6_stable_secret *secret = ctl->data;
6586 
6587 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6588 		return -EIO;
6589 
6590 	lctl.maxlen = IPV6_MAX_STRLEN;
6591 	lctl.data = str;
6592 
6593 	if (!rtnl_net_trylock(net))
6594 		return restart_syscall();
6595 
6596 	if (!write && !secret->initialized) {
6597 		err = -EIO;
6598 		goto out;
6599 	}
6600 
6601 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6602 	if (err >= sizeof(str)) {
6603 		err = -EIO;
6604 		goto out;
6605 	}
6606 
6607 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6608 	if (err || !write)
6609 		goto out;
6610 
6611 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6612 		err = -EIO;
6613 		goto out;
6614 	}
6615 
6616 	secret->initialized = true;
6617 	secret->secret = addr;
6618 
6619 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6620 		struct net_device *dev;
6621 
6622 		for_each_netdev(net, dev) {
6623 			struct inet6_dev *idev = __in6_dev_get_rtnl_net(dev);
6624 
6625 			if (idev) {
6626 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6627 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6628 			}
6629 		}
6630 	} else {
6631 		struct inet6_dev *idev = ctl->extra1;
6632 
6633 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6634 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6635 	}
6636 
6637 out:
6638 	rtnl_net_unlock(net);
6639 
6640 	return err;
6641 }
6642 
6643 static
6644 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6645 						int write, void *buffer,
6646 						size_t *lenp,
6647 						loff_t *ppos)
6648 {
6649 	int *valp = ctl->data;
6650 	int val = *valp;
6651 	loff_t pos = *ppos;
6652 	struct ctl_table lctl;
6653 	int ret;
6654 
6655 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6656 	 * we should not modify it until we get the rtnl lock.
6657 	 */
6658 	lctl = *ctl;
6659 	lctl.data = &val;
6660 
6661 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6662 
6663 	if (write)
6664 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6665 	if (ret)
6666 		*ppos = pos;
6667 	return ret;
6668 }
6669 
6670 static
6671 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6672 {
6673 	if (rt) {
6674 		if (action)
6675 			rt->dst.flags |= DST_NOPOLICY;
6676 		else
6677 			rt->dst.flags &= ~DST_NOPOLICY;
6678 	}
6679 }
6680 
6681 static
6682 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6683 {
6684 	struct inet6_ifaddr *ifa;
6685 
6686 	read_lock_bh(&idev->lock);
6687 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6688 		spin_lock(&ifa->lock);
6689 		if (ifa->rt) {
6690 			/* host routes only use builtin fib6_nh */
6691 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6692 			int cpu;
6693 
6694 			rcu_read_lock();
6695 			ifa->rt->dst_nopolicy = val ? true : false;
6696 			if (nh->rt6i_pcpu) {
6697 				for_each_possible_cpu(cpu) {
6698 					struct rt6_info **rtp;
6699 
6700 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6701 					addrconf_set_nopolicy(*rtp, val);
6702 				}
6703 			}
6704 			rcu_read_unlock();
6705 		}
6706 		spin_unlock(&ifa->lock);
6707 	}
6708 	read_unlock_bh(&idev->lock);
6709 }
6710 
6711 static
6712 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6713 {
6714 	struct net *net = (struct net *)ctl->extra2;
6715 	struct inet6_dev *idev;
6716 
6717 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6718 		WRITE_ONCE(*valp, val);
6719 		return 0;
6720 	}
6721 
6722 	if (!rtnl_net_trylock(net))
6723 		return restart_syscall();
6724 
6725 	WRITE_ONCE(*valp, val);
6726 
6727 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6728 		struct net_device *dev;
6729 
6730 		for_each_netdev(net, dev) {
6731 			idev = __in6_dev_get_rtnl_net(dev);
6732 			if (idev)
6733 				addrconf_disable_policy_idev(idev, val);
6734 		}
6735 	} else {
6736 		idev = (struct inet6_dev *)ctl->extra1;
6737 		addrconf_disable_policy_idev(idev, val);
6738 	}
6739 
6740 	rtnl_net_unlock(net);
6741 	return 0;
6742 }
6743 
6744 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6745 				   void *buffer, size_t *lenp, loff_t *ppos)
6746 {
6747 	int *valp = ctl->data;
6748 	int val = *valp;
6749 	loff_t pos = *ppos;
6750 	struct ctl_table lctl;
6751 	int ret;
6752 
6753 	lctl = *ctl;
6754 	lctl.data = &val;
6755 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6756 
6757 	if (write && (*valp != val))
6758 		ret = addrconf_disable_policy(ctl, valp, val);
6759 
6760 	if (ret)
6761 		*ppos = pos;
6762 
6763 	return ret;
6764 }
6765 
6766 static void addrconf_force_forward_change(struct net *net, __s32 newf)
6767 {
6768 	struct net_device *dev;
6769 	struct inet6_dev *idev;
6770 
6771 	for_each_netdev(net, dev) {
6772 		idev = __in6_dev_get_rtnl_net(dev);
6773 		if (idev) {
6774 			int changed = (!idev->cnf.force_forwarding) ^ (!newf);
6775 
6776 			WRITE_ONCE(idev->cnf.force_forwarding, newf);
6777 			if (changed)
6778 				inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
6779 							     NETCONFA_FORCE_FORWARDING,
6780 							     dev->ifindex, &idev->cnf);
6781 		}
6782 	}
6783 }
6784 
6785 static int addrconf_sysctl_force_forwarding(const struct ctl_table *ctl, int write,
6786 					    void *buffer, size_t *lenp, loff_t *ppos)
6787 {
6788 	struct inet6_dev *idev = ctl->extra1;
6789 	struct ctl_table tmp_ctl = *ctl;
6790 	struct net *net = ctl->extra2;
6791 	int *valp = ctl->data;
6792 	int new_val = *valp;
6793 	int old_val = *valp;
6794 	loff_t pos = *ppos;
6795 	int ret;
6796 
6797 	tmp_ctl.extra1 = SYSCTL_ZERO;
6798 	tmp_ctl.extra2 = SYSCTL_ONE;
6799 	tmp_ctl.data = &new_val;
6800 
6801 	ret = proc_douintvec_minmax(&tmp_ctl, write, buffer, lenp, ppos);
6802 
6803 	if (write && old_val != new_val) {
6804 		if (!rtnl_net_trylock(net))
6805 			return restart_syscall();
6806 
6807 		WRITE_ONCE(*valp, new_val);
6808 
6809 		if (valp == &net->ipv6.devconf_dflt->force_forwarding) {
6810 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6811 						     NETCONFA_FORCE_FORWARDING,
6812 						     NETCONFA_IFINDEX_DEFAULT,
6813 						     net->ipv6.devconf_dflt);
6814 		} else if (valp == &net->ipv6.devconf_all->force_forwarding) {
6815 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6816 						     NETCONFA_FORCE_FORWARDING,
6817 						     NETCONFA_IFINDEX_ALL,
6818 						     net->ipv6.devconf_all);
6819 
6820 			addrconf_force_forward_change(net, new_val);
6821 		} else {
6822 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6823 						     NETCONFA_FORCE_FORWARDING,
6824 						     idev->dev->ifindex,
6825 						     &idev->cnf);
6826 		}
6827 		rtnl_net_unlock(net);
6828 	}
6829 
6830 	if (ret)
6831 		*ppos = pos;
6832 	return ret;
6833 }
6834 
6835 static int minus_one = -1;
6836 static const int two_five_five = 255;
6837 static u32 ioam6_if_id_max = U16_MAX;
6838 
6839 static const struct ctl_table addrconf_sysctl[] = {
6840 	{
6841 		.procname	= "forwarding",
6842 		.data		= &ipv6_devconf.forwarding,
6843 		.maxlen		= sizeof(int),
6844 		.mode		= 0644,
6845 		.proc_handler	= addrconf_sysctl_forward,
6846 	},
6847 	{
6848 		.procname	= "hop_limit",
6849 		.data		= &ipv6_devconf.hop_limit,
6850 		.maxlen		= sizeof(int),
6851 		.mode		= 0644,
6852 		.proc_handler	= proc_dointvec_minmax,
6853 		.extra1		= (void *)SYSCTL_ONE,
6854 		.extra2		= (void *)&two_five_five,
6855 	},
6856 	{
6857 		.procname	= "mtu",
6858 		.data		= &ipv6_devconf.mtu6,
6859 		.maxlen		= sizeof(int),
6860 		.mode		= 0644,
6861 		.proc_handler	= addrconf_sysctl_mtu,
6862 	},
6863 	{
6864 		.procname	= "accept_ra",
6865 		.data		= &ipv6_devconf.accept_ra,
6866 		.maxlen		= sizeof(int),
6867 		.mode		= 0644,
6868 		.proc_handler	= proc_dointvec,
6869 	},
6870 	{
6871 		.procname	= "accept_redirects",
6872 		.data		= &ipv6_devconf.accept_redirects,
6873 		.maxlen		= sizeof(int),
6874 		.mode		= 0644,
6875 		.proc_handler	= proc_dointvec,
6876 	},
6877 	{
6878 		.procname	= "autoconf",
6879 		.data		= &ipv6_devconf.autoconf,
6880 		.maxlen		= sizeof(int),
6881 		.mode		= 0644,
6882 		.proc_handler	= proc_dointvec,
6883 	},
6884 	{
6885 		.procname	= "dad_transmits",
6886 		.data		= &ipv6_devconf.dad_transmits,
6887 		.maxlen		= sizeof(int),
6888 		.mode		= 0644,
6889 		.proc_handler	= proc_dointvec,
6890 	},
6891 	{
6892 		.procname	= "router_solicitations",
6893 		.data		= &ipv6_devconf.rtr_solicits,
6894 		.maxlen		= sizeof(int),
6895 		.mode		= 0644,
6896 		.proc_handler	= proc_dointvec_minmax,
6897 		.extra1		= &minus_one,
6898 	},
6899 	{
6900 		.procname	= "router_solicitation_interval",
6901 		.data		= &ipv6_devconf.rtr_solicit_interval,
6902 		.maxlen		= sizeof(int),
6903 		.mode		= 0644,
6904 		.proc_handler	= proc_dointvec_jiffies,
6905 	},
6906 	{
6907 		.procname	= "router_solicitation_max_interval",
6908 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6909 		.maxlen		= sizeof(int),
6910 		.mode		= 0644,
6911 		.proc_handler	= proc_dointvec_jiffies,
6912 	},
6913 	{
6914 		.procname	= "router_solicitation_delay",
6915 		.data		= &ipv6_devconf.rtr_solicit_delay,
6916 		.maxlen		= sizeof(int),
6917 		.mode		= 0644,
6918 		.proc_handler	= proc_dointvec_jiffies,
6919 	},
6920 	{
6921 		.procname	= "force_mld_version",
6922 		.data		= &ipv6_devconf.force_mld_version,
6923 		.maxlen		= sizeof(int),
6924 		.mode		= 0644,
6925 		.proc_handler	= proc_dointvec,
6926 	},
6927 	{
6928 		.procname	= "mldv1_unsolicited_report_interval",
6929 		.data		=
6930 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6931 		.maxlen		= sizeof(int),
6932 		.mode		= 0644,
6933 		.proc_handler	= proc_dointvec_ms_jiffies,
6934 	},
6935 	{
6936 		.procname	= "mldv2_unsolicited_report_interval",
6937 		.data		=
6938 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6939 		.maxlen		= sizeof(int),
6940 		.mode		= 0644,
6941 		.proc_handler	= proc_dointvec_ms_jiffies,
6942 	},
6943 	{
6944 		.procname	= "use_tempaddr",
6945 		.data		= &ipv6_devconf.use_tempaddr,
6946 		.maxlen		= sizeof(int),
6947 		.mode		= 0644,
6948 		.proc_handler	= proc_dointvec,
6949 	},
6950 	{
6951 		.procname	= "temp_valid_lft",
6952 		.data		= &ipv6_devconf.temp_valid_lft,
6953 		.maxlen		= sizeof(int),
6954 		.mode		= 0644,
6955 		.proc_handler	= proc_dointvec,
6956 	},
6957 	{
6958 		.procname	= "temp_prefered_lft",
6959 		.data		= &ipv6_devconf.temp_prefered_lft,
6960 		.maxlen		= sizeof(int),
6961 		.mode		= 0644,
6962 		.proc_handler	= proc_dointvec,
6963 	},
6964 	{
6965 		.procname       = "regen_min_advance",
6966 		.data           = &ipv6_devconf.regen_min_advance,
6967 		.maxlen         = sizeof(int),
6968 		.mode           = 0644,
6969 		.proc_handler   = proc_dointvec,
6970 	},
6971 	{
6972 		.procname	= "regen_max_retry",
6973 		.data		= &ipv6_devconf.regen_max_retry,
6974 		.maxlen		= sizeof(int),
6975 		.mode		= 0644,
6976 		.proc_handler	= proc_dointvec,
6977 	},
6978 	{
6979 		.procname	= "max_desync_factor",
6980 		.data		= &ipv6_devconf.max_desync_factor,
6981 		.maxlen		= sizeof(int),
6982 		.mode		= 0644,
6983 		.proc_handler	= proc_dointvec,
6984 	},
6985 	{
6986 		.procname	= "max_addresses",
6987 		.data		= &ipv6_devconf.max_addresses,
6988 		.maxlen		= sizeof(int),
6989 		.mode		= 0644,
6990 		.proc_handler	= proc_dointvec,
6991 	},
6992 	{
6993 		.procname	= "accept_ra_defrtr",
6994 		.data		= &ipv6_devconf.accept_ra_defrtr,
6995 		.maxlen		= sizeof(int),
6996 		.mode		= 0644,
6997 		.proc_handler	= proc_dointvec,
6998 	},
6999 	{
7000 		.procname	= "ra_defrtr_metric",
7001 		.data		= &ipv6_devconf.ra_defrtr_metric,
7002 		.maxlen		= sizeof(u32),
7003 		.mode		= 0644,
7004 		.proc_handler	= proc_douintvec_minmax,
7005 		.extra1		= (void *)SYSCTL_ONE,
7006 	},
7007 	{
7008 		.procname	= "accept_ra_min_hop_limit",
7009 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
7010 		.maxlen		= sizeof(int),
7011 		.mode		= 0644,
7012 		.proc_handler	= proc_dointvec,
7013 	},
7014 	{
7015 		.procname	= "accept_ra_min_lft",
7016 		.data		= &ipv6_devconf.accept_ra_min_lft,
7017 		.maxlen		= sizeof(int),
7018 		.mode		= 0644,
7019 		.proc_handler	= proc_dointvec,
7020 	},
7021 	{
7022 		.procname	= "accept_ra_pinfo",
7023 		.data		= &ipv6_devconf.accept_ra_pinfo,
7024 		.maxlen		= sizeof(int),
7025 		.mode		= 0644,
7026 		.proc_handler	= proc_dointvec,
7027 	},
7028 	{
7029 		.procname	= "ra_honor_pio_life",
7030 		.data		= &ipv6_devconf.ra_honor_pio_life,
7031 		.maxlen		= sizeof(u8),
7032 		.mode		= 0644,
7033 		.proc_handler	= proc_dou8vec_minmax,
7034 		.extra1		= SYSCTL_ZERO,
7035 		.extra2		= SYSCTL_ONE,
7036 	},
7037 	{
7038 		.procname	= "ra_honor_pio_pflag",
7039 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
7040 		.maxlen		= sizeof(u8),
7041 		.mode		= 0644,
7042 		.proc_handler	= proc_dou8vec_minmax,
7043 		.extra1		= SYSCTL_ZERO,
7044 		.extra2		= SYSCTL_ONE,
7045 	},
7046 #ifdef CONFIG_IPV6_ROUTER_PREF
7047 	{
7048 		.procname	= "accept_ra_rtr_pref",
7049 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
7050 		.maxlen		= sizeof(int),
7051 		.mode		= 0644,
7052 		.proc_handler	= proc_dointvec,
7053 	},
7054 	{
7055 		.procname	= "router_probe_interval",
7056 		.data		= &ipv6_devconf.rtr_probe_interval,
7057 		.maxlen		= sizeof(int),
7058 		.mode		= 0644,
7059 		.proc_handler	= proc_dointvec_jiffies,
7060 	},
7061 #ifdef CONFIG_IPV6_ROUTE_INFO
7062 	{
7063 		.procname	= "accept_ra_rt_info_min_plen",
7064 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
7065 		.maxlen		= sizeof(int),
7066 		.mode		= 0644,
7067 		.proc_handler	= proc_dointvec,
7068 	},
7069 	{
7070 		.procname	= "accept_ra_rt_info_max_plen",
7071 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
7072 		.maxlen		= sizeof(int),
7073 		.mode		= 0644,
7074 		.proc_handler	= proc_dointvec,
7075 	},
7076 #endif
7077 #endif
7078 	{
7079 		.procname	= "proxy_ndp",
7080 		.data		= &ipv6_devconf.proxy_ndp,
7081 		.maxlen		= sizeof(int),
7082 		.mode		= 0644,
7083 		.proc_handler	= addrconf_sysctl_proxy_ndp,
7084 	},
7085 	{
7086 		.procname	= "accept_source_route",
7087 		.data		= &ipv6_devconf.accept_source_route,
7088 		.maxlen		= sizeof(int),
7089 		.mode		= 0644,
7090 		.proc_handler	= proc_dointvec,
7091 	},
7092 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
7093 	{
7094 		.procname	= "optimistic_dad",
7095 		.data		= &ipv6_devconf.optimistic_dad,
7096 		.maxlen		= sizeof(int),
7097 		.mode		= 0644,
7098 		.proc_handler   = proc_dointvec,
7099 	},
7100 	{
7101 		.procname	= "use_optimistic",
7102 		.data		= &ipv6_devconf.use_optimistic,
7103 		.maxlen		= sizeof(int),
7104 		.mode		= 0644,
7105 		.proc_handler	= proc_dointvec,
7106 	},
7107 #endif
7108 #ifdef CONFIG_IPV6_MROUTE
7109 	{
7110 		.procname	= "mc_forwarding",
7111 		.data		= &ipv6_devconf.mc_forwarding,
7112 		.maxlen		= sizeof(int),
7113 		.mode		= 0444,
7114 		.proc_handler	= proc_dointvec,
7115 	},
7116 #endif
7117 	{
7118 		.procname	= "disable_ipv6",
7119 		.data		= &ipv6_devconf.disable_ipv6,
7120 		.maxlen		= sizeof(int),
7121 		.mode		= 0644,
7122 		.proc_handler	= addrconf_sysctl_disable,
7123 	},
7124 	{
7125 		.procname	= "accept_dad",
7126 		.data		= &ipv6_devconf.accept_dad,
7127 		.maxlen		= sizeof(int),
7128 		.mode		= 0644,
7129 		.proc_handler	= proc_dointvec,
7130 	},
7131 	{
7132 		.procname	= "force_tllao",
7133 		.data		= &ipv6_devconf.force_tllao,
7134 		.maxlen		= sizeof(int),
7135 		.mode		= 0644,
7136 		.proc_handler	= proc_dointvec
7137 	},
7138 	{
7139 		.procname	= "ndisc_notify",
7140 		.data		= &ipv6_devconf.ndisc_notify,
7141 		.maxlen		= sizeof(int),
7142 		.mode		= 0644,
7143 		.proc_handler	= proc_dointvec
7144 	},
7145 	{
7146 		.procname	= "suppress_frag_ndisc",
7147 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7148 		.maxlen		= sizeof(int),
7149 		.mode		= 0644,
7150 		.proc_handler	= proc_dointvec
7151 	},
7152 	{
7153 		.procname	= "accept_ra_from_local",
7154 		.data		= &ipv6_devconf.accept_ra_from_local,
7155 		.maxlen		= sizeof(int),
7156 		.mode		= 0644,
7157 		.proc_handler	= proc_dointvec,
7158 	},
7159 	{
7160 		.procname	= "accept_ra_mtu",
7161 		.data		= &ipv6_devconf.accept_ra_mtu,
7162 		.maxlen		= sizeof(int),
7163 		.mode		= 0644,
7164 		.proc_handler	= proc_dointvec,
7165 	},
7166 	{
7167 		.procname	= "stable_secret",
7168 		.data		= &ipv6_devconf.stable_secret,
7169 		.maxlen		= IPV6_MAX_STRLEN,
7170 		.mode		= 0600,
7171 		.proc_handler	= addrconf_sysctl_stable_secret,
7172 	},
7173 	{
7174 		.procname	= "use_oif_addrs_only",
7175 		.data		= &ipv6_devconf.use_oif_addrs_only,
7176 		.maxlen		= sizeof(int),
7177 		.mode		= 0644,
7178 		.proc_handler	= proc_dointvec,
7179 	},
7180 	{
7181 		.procname	= "ignore_routes_with_linkdown",
7182 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7183 		.maxlen		= sizeof(int),
7184 		.mode		= 0644,
7185 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7186 	},
7187 	{
7188 		.procname	= "drop_unicast_in_l2_multicast",
7189 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7190 		.maxlen		= sizeof(int),
7191 		.mode		= 0644,
7192 		.proc_handler	= proc_dointvec,
7193 	},
7194 	{
7195 		.procname	= "drop_unsolicited_na",
7196 		.data		= &ipv6_devconf.drop_unsolicited_na,
7197 		.maxlen		= sizeof(int),
7198 		.mode		= 0644,
7199 		.proc_handler	= proc_dointvec,
7200 	},
7201 	{
7202 		.procname	= "keep_addr_on_down",
7203 		.data		= &ipv6_devconf.keep_addr_on_down,
7204 		.maxlen		= sizeof(int),
7205 		.mode		= 0644,
7206 		.proc_handler	= proc_dointvec,
7207 
7208 	},
7209 	{
7210 		.procname	= "seg6_enabled",
7211 		.data		= &ipv6_devconf.seg6_enabled,
7212 		.maxlen		= sizeof(int),
7213 		.mode		= 0644,
7214 		.proc_handler	= proc_dointvec,
7215 	},
7216 #ifdef CONFIG_IPV6_SEG6_HMAC
7217 	{
7218 		.procname	= "seg6_require_hmac",
7219 		.data		= &ipv6_devconf.seg6_require_hmac,
7220 		.maxlen		= sizeof(int),
7221 		.mode		= 0644,
7222 		.proc_handler	= proc_dointvec,
7223 	},
7224 #endif
7225 	{
7226 		.procname       = "enhanced_dad",
7227 		.data           = &ipv6_devconf.enhanced_dad,
7228 		.maxlen         = sizeof(int),
7229 		.mode           = 0644,
7230 		.proc_handler   = proc_dointvec,
7231 	},
7232 	{
7233 		.procname	= "addr_gen_mode",
7234 		.data		= &ipv6_devconf.addr_gen_mode,
7235 		.maxlen		= sizeof(int),
7236 		.mode		= 0644,
7237 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7238 	},
7239 	{
7240 		.procname       = "disable_policy",
7241 		.data           = &ipv6_devconf.disable_policy,
7242 		.maxlen         = sizeof(int),
7243 		.mode           = 0644,
7244 		.proc_handler   = addrconf_sysctl_disable_policy,
7245 	},
7246 	{
7247 		.procname	= "ndisc_tclass",
7248 		.data		= &ipv6_devconf.ndisc_tclass,
7249 		.maxlen		= sizeof(int),
7250 		.mode		= 0644,
7251 		.proc_handler	= proc_dointvec_minmax,
7252 		.extra1		= (void *)SYSCTL_ZERO,
7253 		.extra2		= (void *)&two_five_five,
7254 	},
7255 	{
7256 		.procname	= "rpl_seg_enabled",
7257 		.data		= &ipv6_devconf.rpl_seg_enabled,
7258 		.maxlen		= sizeof(int),
7259 		.mode		= 0644,
7260 		.proc_handler   = proc_dointvec_minmax,
7261 		.extra1         = SYSCTL_ZERO,
7262 		.extra2         = SYSCTL_ONE,
7263 	},
7264 	{
7265 		.procname	= "ioam6_enabled",
7266 		.data		= &ipv6_devconf.ioam6_enabled,
7267 		.maxlen		= sizeof(u8),
7268 		.mode		= 0644,
7269 		.proc_handler	= proc_dou8vec_minmax,
7270 		.extra1		= (void *)SYSCTL_ZERO,
7271 		.extra2		= (void *)SYSCTL_ONE,
7272 	},
7273 	{
7274 		.procname	= "ioam6_id",
7275 		.data		= &ipv6_devconf.ioam6_id,
7276 		.maxlen		= sizeof(u32),
7277 		.mode		= 0644,
7278 		.proc_handler	= proc_douintvec_minmax,
7279 		.extra1		= (void *)SYSCTL_ZERO,
7280 		.extra2		= (void *)&ioam6_if_id_max,
7281 	},
7282 	{
7283 		.procname	= "ioam6_id_wide",
7284 		.data		= &ipv6_devconf.ioam6_id_wide,
7285 		.maxlen		= sizeof(u32),
7286 		.mode		= 0644,
7287 		.proc_handler	= proc_douintvec,
7288 	},
7289 	{
7290 		.procname	= "ndisc_evict_nocarrier",
7291 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7292 		.maxlen		= sizeof(u8),
7293 		.mode		= 0644,
7294 		.proc_handler	= proc_dou8vec_minmax,
7295 		.extra1		= (void *)SYSCTL_ZERO,
7296 		.extra2		= (void *)SYSCTL_ONE,
7297 	},
7298 	{
7299 		.procname	= "accept_untracked_na",
7300 		.data		= &ipv6_devconf.accept_untracked_na,
7301 		.maxlen		= sizeof(int),
7302 		.mode		= 0644,
7303 		.proc_handler	= proc_dointvec_minmax,
7304 		.extra1		= SYSCTL_ZERO,
7305 		.extra2		= SYSCTL_TWO,
7306 	},
7307 	{
7308 		.procname	= "force_forwarding",
7309 		.data		= &ipv6_devconf.force_forwarding,
7310 		.maxlen		= sizeof(int),
7311 		.mode		= 0644,
7312 		.proc_handler	= addrconf_sysctl_force_forwarding,
7313 	},
7314 };
7315 
7316 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7317 		struct inet6_dev *idev, struct ipv6_devconf *p)
7318 {
7319 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7320 	int i, ifindex;
7321 	struct ctl_table *table;
7322 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7323 
7324 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7325 	if (!table)
7326 		goto out;
7327 
7328 	for (i = 0; i < table_size; i++) {
7329 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7330 		/* If one of these is already set, then it is not safe to
7331 		 * overwrite either of them: this makes proc_dointvec_minmax
7332 		 * usable.
7333 		 */
7334 		if (!table[i].extra1 && !table[i].extra2) {
7335 			table[i].extra1 = idev; /* embedded; no ref */
7336 			table[i].extra2 = net;
7337 		}
7338 	}
7339 
7340 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7341 
7342 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7343 						  table_size);
7344 	if (!p->sysctl_header)
7345 		goto free;
7346 
7347 	if (!strcmp(dev_name, "all"))
7348 		ifindex = NETCONFA_IFINDEX_ALL;
7349 	else if (!strcmp(dev_name, "default"))
7350 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7351 	else
7352 		ifindex = idev->dev->ifindex;
7353 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7354 				     ifindex, p);
7355 	return 0;
7356 
7357 free:
7358 	kfree(table);
7359 out:
7360 	return -ENOBUFS;
7361 }
7362 
7363 static void __addrconf_sysctl_unregister(struct net *net,
7364 					 struct ipv6_devconf *p, int ifindex)
7365 {
7366 	const struct ctl_table *table;
7367 
7368 	if (!p->sysctl_header)
7369 		return;
7370 
7371 	table = p->sysctl_header->ctl_table_arg;
7372 	unregister_net_sysctl_table(p->sysctl_header);
7373 	p->sysctl_header = NULL;
7374 	kfree(table);
7375 
7376 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7377 }
7378 
7379 static int addrconf_sysctl_register(struct inet6_dev *idev)
7380 {
7381 	int err;
7382 
7383 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7384 		return -EINVAL;
7385 
7386 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7387 				    &ndisc_ifinfo_sysctl_change);
7388 	if (err)
7389 		return err;
7390 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7391 					 idev, &idev->cnf);
7392 	if (err)
7393 		neigh_sysctl_unregister(idev->nd_parms);
7394 
7395 	return err;
7396 }
7397 
7398 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7399 {
7400 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7401 				     idev->dev->ifindex);
7402 	neigh_sysctl_unregister(idev->nd_parms);
7403 }
7404 
7405 
7406 #endif
7407 
7408 static int __net_init addrconf_init_net(struct net *net)
7409 {
7410 	int err = -ENOMEM;
7411 	struct ipv6_devconf *all, *dflt;
7412 
7413 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7414 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7415 	net->ipv6.inet6_addr_lst = kzalloc_objs(struct hlist_head,
7416 						IN6_ADDR_HSIZE);
7417 	if (!net->ipv6.inet6_addr_lst)
7418 		goto err_alloc_addr;
7419 
7420 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7421 	if (!all)
7422 		goto err_alloc_all;
7423 
7424 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7425 	if (!dflt)
7426 		goto err_alloc_dflt;
7427 
7428 	if (!net_eq(net, &init_net)) {
7429 		switch (net_inherit_devconf()) {
7430 		case 1:  /* copy from init_net */
7431 			memcpy(all, init_net.ipv6.devconf_all,
7432 			       sizeof(ipv6_devconf));
7433 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7434 			       sizeof(ipv6_devconf_dflt));
7435 			break;
7436 		case 3: /* copy from the current netns */
7437 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7438 			       sizeof(ipv6_devconf));
7439 			memcpy(dflt,
7440 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7441 			       sizeof(ipv6_devconf_dflt));
7442 			break;
7443 		case 0:
7444 		case 2:
7445 			/* use compiled values */
7446 			break;
7447 		}
7448 	}
7449 
7450 	/* these will be inherited by all namespaces */
7451 	dflt->autoconf = ipv6_defaults.autoconf;
7452 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7453 
7454 	dflt->stable_secret.initialized = false;
7455 	all->stable_secret.initialized = false;
7456 
7457 	net->ipv6.devconf_all = all;
7458 	net->ipv6.devconf_dflt = dflt;
7459 
7460 #ifdef CONFIG_SYSCTL
7461 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7462 	if (err < 0)
7463 		goto err_reg_all;
7464 
7465 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7466 	if (err < 0)
7467 		goto err_reg_dflt;
7468 #endif
7469 	return 0;
7470 
7471 #ifdef CONFIG_SYSCTL
7472 err_reg_dflt:
7473 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7474 err_reg_all:
7475 	kfree(dflt);
7476 	net->ipv6.devconf_dflt = NULL;
7477 #endif
7478 err_alloc_dflt:
7479 	kfree(all);
7480 	net->ipv6.devconf_all = NULL;
7481 err_alloc_all:
7482 	kfree(net->ipv6.inet6_addr_lst);
7483 err_alloc_addr:
7484 	return err;
7485 }
7486 
7487 static void __net_exit addrconf_exit_net(struct net *net)
7488 {
7489 	int i;
7490 
7491 #ifdef CONFIG_SYSCTL
7492 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7493 				     NETCONFA_IFINDEX_DEFAULT);
7494 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7495 				     NETCONFA_IFINDEX_ALL);
7496 #endif
7497 	kfree(net->ipv6.devconf_dflt);
7498 	net->ipv6.devconf_dflt = NULL;
7499 	kfree(net->ipv6.devconf_all);
7500 	net->ipv6.devconf_all = NULL;
7501 
7502 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7503 	/*
7504 	 *	Check hash table, then free it.
7505 	 */
7506 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7507 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7508 
7509 	kfree(net->ipv6.inet6_addr_lst);
7510 	net->ipv6.inet6_addr_lst = NULL;
7511 }
7512 
7513 static struct pernet_operations addrconf_ops = {
7514 	.init = addrconf_init_net,
7515 	.exit = addrconf_exit_net,
7516 };
7517 
7518 static struct rtnl_af_ops inet6_ops __read_mostly = {
7519 	.family		  = AF_INET6,
7520 	.fill_link_af	  = inet6_fill_link_af,
7521 	.get_link_af_size = inet6_get_link_af_size,
7522 	.validate_link_af = inet6_validate_link_af,
7523 	.set_link_af	  = inet6_set_link_af,
7524 };
7525 
7526 static const struct rtnl_msg_handler addrconf_rtnl_msg_handlers[] __initconst_or_module = {
7527 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETLINK,
7528 	 .dumpit = inet6_dump_ifinfo, .flags = RTNL_FLAG_DUMP_UNLOCKED},
7529 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDR,
7530 	 .doit = inet6_rtm_newaddr, .flags = RTNL_FLAG_DOIT_PERNET},
7531 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDR,
7532 	 .doit = inet6_rtm_deladdr, .flags = RTNL_FLAG_DOIT_PERNET},
7533 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDR,
7534 	 .doit = inet6_rtm_getaddr, .dumpit = inet6_dump_ifaddr,
7535 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7536 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETMULTICAST,
7537 	 .dumpit = inet6_dump_ifmcaddr,
7538 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7539 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETANYCAST,
7540 	 .dumpit = inet6_dump_ifacaddr,
7541 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7542 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETNETCONF,
7543 	 .doit = inet6_netconf_get_devconf, .dumpit = inet6_netconf_dump_devconf,
7544 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7545 };
7546 
7547 /*
7548  *	Init / cleanup code
7549  */
7550 
7551 int __init addrconf_init(void)
7552 {
7553 	struct inet6_dev *idev;
7554 	int err;
7555 
7556 	err = ipv6_addr_label_init();
7557 	if (err < 0) {
7558 		pr_crit("%s: cannot initialize default policy table: %d\n",
7559 			__func__, err);
7560 		goto out;
7561 	}
7562 
7563 	err = register_pernet_subsys(&addrconf_ops);
7564 	if (err < 0)
7565 		goto out_addrlabel;
7566 
7567 	/* All works using addrconf_wq need to lock rtnl. */
7568 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7569 	if (!addrconf_wq) {
7570 		err = -ENOMEM;
7571 		goto out_nowq;
7572 	}
7573 
7574 	rtnl_net_lock(&init_net);
7575 	idev = ipv6_add_dev(blackhole_netdev);
7576 	rtnl_net_unlock(&init_net);
7577 	if (IS_ERR(idev)) {
7578 		err = PTR_ERR(idev);
7579 		goto errlo;
7580 	}
7581 
7582 	ip6_route_init_special_entries();
7583 
7584 	register_netdevice_notifier(&ipv6_dev_notf);
7585 
7586 	addrconf_verify(&init_net);
7587 
7588 	err = rtnl_af_register(&inet6_ops);
7589 	if (err)
7590 		goto erraf;
7591 
7592 	err = rtnl_register_many(addrconf_rtnl_msg_handlers);
7593 	if (err)
7594 		goto errout;
7595 
7596 	err = ipv6_addr_label_rtnl_register();
7597 	if (err < 0)
7598 		goto errout;
7599 
7600 	return 0;
7601 errout:
7602 	rtnl_unregister_all(PF_INET6);
7603 	rtnl_af_unregister(&inet6_ops);
7604 erraf:
7605 	unregister_netdevice_notifier(&ipv6_dev_notf);
7606 errlo:
7607 	destroy_workqueue(addrconf_wq);
7608 out_nowq:
7609 	unregister_pernet_subsys(&addrconf_ops);
7610 out_addrlabel:
7611 	ipv6_addr_label_cleanup();
7612 out:
7613 	return err;
7614 }
7615 
7616 void addrconf_cleanup(void)
7617 {
7618 	struct net_device *dev;
7619 
7620 	unregister_netdevice_notifier(&ipv6_dev_notf);
7621 	unregister_pernet_subsys(&addrconf_ops);
7622 	ipv6_addr_label_cleanup();
7623 
7624 	rtnl_af_unregister(&inet6_ops);
7625 
7626 	rtnl_net_lock(&init_net);
7627 
7628 	/* clean dev list */
7629 	for_each_netdev(&init_net, dev) {
7630 		if (!__in6_dev_get_rtnl_net(dev))
7631 			continue;
7632 		addrconf_ifdown(dev, true);
7633 	}
7634 	addrconf_ifdown(init_net.loopback_dev, true);
7635 
7636 	rtnl_net_unlock(&init_net);
7637 
7638 	destroy_workqueue(addrconf_wq);
7639 }
7640