xref: /linux/net/ipv6/addrconf.c (revision 6ca80638b90cec66547011ee1ef79e534589989a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 #include <linux/ioam6.h>
93 
94 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
95 
96 #define IPV6_MAX_STRLEN \
97 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
98 
99 static inline u32 cstamp_delta(unsigned long cstamp)
100 {
101 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
102 }
103 
104 static inline s32 rfc3315_s14_backoff_init(s32 irt)
105 {
106 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
107 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
108 	do_div(tmp, 1000000);
109 	return (s32)tmp;
110 }
111 
112 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
113 {
114 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
115 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
116 	do_div(tmp, 1000000);
117 	if ((s32)tmp > mrt) {
118 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
119 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
120 		do_div(tmp, 1000000);
121 	}
122 	return (s32)tmp;
123 }
124 
125 #ifdef CONFIG_SYSCTL
126 static int addrconf_sysctl_register(struct inet6_dev *idev);
127 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
128 #else
129 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
130 {
131 	return 0;
132 }
133 
134 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
135 {
136 }
137 #endif
138 
139 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 
150 static void addrconf_verify(struct net *net);
151 static void addrconf_verify_rtnl(struct net *net);
152 
153 static struct workqueue_struct *addrconf_wq;
154 
155 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
156 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
157 
158 static void addrconf_type_change(struct net_device *dev,
159 				 unsigned long event);
160 static int addrconf_ifdown(struct net_device *dev, bool unregister);
161 
162 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
163 						  int plen,
164 						  const struct net_device *dev,
165 						  u32 flags, u32 noflags,
166 						  bool no_gw);
167 
168 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
169 static void addrconf_dad_work(struct work_struct *w);
170 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
171 				   bool send_na);
172 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
173 static void addrconf_rs_timer(struct timer_list *t);
174 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
175 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
176 
177 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
178 				struct prefix_info *pinfo);
179 
180 static struct ipv6_devconf ipv6_devconf __read_mostly = {
181 	.forwarding		= 0,
182 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
183 	.mtu6			= IPV6_MIN_MTU,
184 	.accept_ra		= 1,
185 	.accept_redirects	= 1,
186 	.autoconf		= 1,
187 	.force_mld_version	= 0,
188 	.mldv1_unsolicited_report_interval = 10 * HZ,
189 	.mldv2_unsolicited_report_interval = HZ,
190 	.dad_transmits		= 1,
191 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
192 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
193 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
194 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
195 	.use_tempaddr		= 0,
196 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
197 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
198 	.regen_max_retry	= REGEN_MAX_RETRY,
199 	.max_desync_factor	= MAX_DESYNC_FACTOR,
200 	.max_addresses		= IPV6_MAX_ADDRESSES,
201 	.accept_ra_defrtr	= 1,
202 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
203 	.accept_ra_from_local	= 0,
204 	.accept_ra_min_hop_limit= 1,
205 	.accept_ra_min_lft	= 0,
206 	.accept_ra_pinfo	= 1,
207 #ifdef CONFIG_IPV6_ROUTER_PREF
208 	.accept_ra_rtr_pref	= 1,
209 	.rtr_probe_interval	= 60 * HZ,
210 #ifdef CONFIG_IPV6_ROUTE_INFO
211 	.accept_ra_rt_info_min_plen = 0,
212 	.accept_ra_rt_info_max_plen = 0,
213 #endif
214 #endif
215 	.proxy_ndp		= 0,
216 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
217 	.disable_ipv6		= 0,
218 	.accept_dad		= 0,
219 	.suppress_frag_ndisc	= 1,
220 	.accept_ra_mtu		= 1,
221 	.stable_secret		= {
222 		.initialized = false,
223 	},
224 	.use_oif_addrs_only	= 0,
225 	.ignore_routes_with_linkdown = 0,
226 	.keep_addr_on_down	= 0,
227 	.seg6_enabled		= 0,
228 #ifdef CONFIG_IPV6_SEG6_HMAC
229 	.seg6_require_hmac	= 0,
230 #endif
231 	.enhanced_dad           = 1,
232 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
233 	.disable_policy		= 0,
234 	.rpl_seg_enabled	= 0,
235 	.ioam6_enabled		= 0,
236 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
237 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
238 	.ndisc_evict_nocarrier	= 1,
239 	.ra_honor_pio_life	= 0,
240 };
241 
242 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
243 	.forwarding		= 0,
244 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
245 	.mtu6			= IPV6_MIN_MTU,
246 	.accept_ra		= 1,
247 	.accept_redirects	= 1,
248 	.autoconf		= 1,
249 	.force_mld_version	= 0,
250 	.mldv1_unsolicited_report_interval = 10 * HZ,
251 	.mldv2_unsolicited_report_interval = HZ,
252 	.dad_transmits		= 1,
253 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
254 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
255 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
256 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
257 	.use_tempaddr		= 0,
258 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
259 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
260 	.regen_max_retry	= REGEN_MAX_RETRY,
261 	.max_desync_factor	= MAX_DESYNC_FACTOR,
262 	.max_addresses		= IPV6_MAX_ADDRESSES,
263 	.accept_ra_defrtr	= 1,
264 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
265 	.accept_ra_from_local	= 0,
266 	.accept_ra_min_hop_limit= 1,
267 	.accept_ra_min_lft	= 0,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 	.rpl_seg_enabled	= 0,
297 	.ioam6_enabled		= 0,
298 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
299 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
300 	.ndisc_evict_nocarrier	= 1,
301 	.ra_honor_pio_life	= 0,
302 };
303 
304 /* Check if link is ready: is it up and is a valid qdisc available */
305 static inline bool addrconf_link_ready(const struct net_device *dev)
306 {
307 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
308 }
309 
310 static void addrconf_del_rs_timer(struct inet6_dev *idev)
311 {
312 	if (del_timer(&idev->rs_timer))
313 		__in6_dev_put(idev);
314 }
315 
316 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
317 {
318 	if (cancel_delayed_work(&ifp->dad_work))
319 		__in6_ifa_put(ifp);
320 }
321 
322 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
323 				  unsigned long when)
324 {
325 	if (!mod_timer(&idev->rs_timer, jiffies + when))
326 		in6_dev_hold(idev);
327 }
328 
329 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
330 				   unsigned long delay)
331 {
332 	in6_ifa_hold(ifp);
333 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
334 		in6_ifa_put(ifp);
335 }
336 
337 static int snmp6_alloc_dev(struct inet6_dev *idev)
338 {
339 	int i;
340 
341 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
342 	if (!idev->stats.ipv6)
343 		goto err_ip;
344 
345 	for_each_possible_cpu(i) {
346 		struct ipstats_mib *addrconf_stats;
347 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
348 		u64_stats_init(&addrconf_stats->syncp);
349 	}
350 
351 
352 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
353 					GFP_KERNEL);
354 	if (!idev->stats.icmpv6dev)
355 		goto err_icmp;
356 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
357 					   GFP_KERNEL_ACCOUNT);
358 	if (!idev->stats.icmpv6msgdev)
359 		goto err_icmpmsg;
360 
361 	return 0;
362 
363 err_icmpmsg:
364 	kfree(idev->stats.icmpv6dev);
365 err_icmp:
366 	free_percpu(idev->stats.ipv6);
367 err_ip:
368 	return -ENOMEM;
369 }
370 
371 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
372 {
373 	struct inet6_dev *ndev;
374 	int err = -ENOMEM;
375 
376 	ASSERT_RTNL();
377 
378 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
379 		return ERR_PTR(-EINVAL);
380 
381 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
382 	if (!ndev)
383 		return ERR_PTR(err);
384 
385 	rwlock_init(&ndev->lock);
386 	ndev->dev = dev;
387 	INIT_LIST_HEAD(&ndev->addr_list);
388 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
389 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
390 
391 	if (ndev->cnf.stable_secret.initialized)
392 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
393 
394 	ndev->cnf.mtu6 = dev->mtu;
395 	ndev->ra_mtu = 0;
396 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
397 	if (!ndev->nd_parms) {
398 		kfree(ndev);
399 		return ERR_PTR(err);
400 	}
401 	if (ndev->cnf.forwarding)
402 		dev_disable_lro(dev);
403 	/* We refer to the device */
404 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
405 
406 	if (snmp6_alloc_dev(ndev) < 0) {
407 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
408 			   __func__);
409 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
410 		netdev_put(dev, &ndev->dev_tracker);
411 		kfree(ndev);
412 		return ERR_PTR(err);
413 	}
414 
415 	if (dev != blackhole_netdev) {
416 		if (snmp6_register_dev(ndev) < 0) {
417 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
418 				   __func__, dev->name);
419 			goto err_release;
420 		}
421 	}
422 	/* One reference from device. */
423 	refcount_set(&ndev->refcnt, 1);
424 
425 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
426 		ndev->cnf.accept_dad = -1;
427 
428 #if IS_ENABLED(CONFIG_IPV6_SIT)
429 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
430 		pr_info("%s: Disabled Multicast RS\n", dev->name);
431 		ndev->cnf.rtr_solicits = 0;
432 	}
433 #endif
434 
435 	INIT_LIST_HEAD(&ndev->tempaddr_list);
436 	ndev->desync_factor = U32_MAX;
437 	if ((dev->flags&IFF_LOOPBACK) ||
438 	    dev->type == ARPHRD_TUNNEL ||
439 	    dev->type == ARPHRD_TUNNEL6 ||
440 	    dev->type == ARPHRD_SIT ||
441 	    dev->type == ARPHRD_NONE) {
442 		ndev->cnf.use_tempaddr = -1;
443 	}
444 
445 	ndev->token = in6addr_any;
446 
447 	if (netif_running(dev) && addrconf_link_ready(dev))
448 		ndev->if_flags |= IF_READY;
449 
450 	ipv6_mc_init_dev(ndev);
451 	ndev->tstamp = jiffies;
452 	if (dev != blackhole_netdev) {
453 		err = addrconf_sysctl_register(ndev);
454 		if (err) {
455 			ipv6_mc_destroy_dev(ndev);
456 			snmp6_unregister_dev(ndev);
457 			goto err_release;
458 		}
459 	}
460 	/* protected by rtnl_lock */
461 	rcu_assign_pointer(dev->ip6_ptr, ndev);
462 
463 	if (dev != blackhole_netdev) {
464 		/* Join interface-local all-node multicast group */
465 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
466 
467 		/* Join all-node multicast group */
468 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
469 
470 		/* Join all-router multicast group if forwarding is set */
471 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
472 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
473 	}
474 	return ndev;
475 
476 err_release:
477 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
478 	ndev->dead = 1;
479 	in6_dev_finish_destroy(ndev);
480 	return ERR_PTR(err);
481 }
482 
483 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
484 {
485 	struct inet6_dev *idev;
486 
487 	ASSERT_RTNL();
488 
489 	idev = __in6_dev_get(dev);
490 	if (!idev) {
491 		idev = ipv6_add_dev(dev);
492 		if (IS_ERR(idev))
493 			return idev;
494 	}
495 
496 	if (dev->flags&IFF_UP)
497 		ipv6_mc_up(idev);
498 	return idev;
499 }
500 
501 static int inet6_netconf_msgsize_devconf(int type)
502 {
503 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
504 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
505 	bool all = false;
506 
507 	if (type == NETCONFA_ALL)
508 		all = true;
509 
510 	if (all || type == NETCONFA_FORWARDING)
511 		size += nla_total_size(4);
512 #ifdef CONFIG_IPV6_MROUTE
513 	if (all || type == NETCONFA_MC_FORWARDING)
514 		size += nla_total_size(4);
515 #endif
516 	if (all || type == NETCONFA_PROXY_NEIGH)
517 		size += nla_total_size(4);
518 
519 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
520 		size += nla_total_size(4);
521 
522 	return size;
523 }
524 
525 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
526 				      struct ipv6_devconf *devconf, u32 portid,
527 				      u32 seq, int event, unsigned int flags,
528 				      int type)
529 {
530 	struct nlmsghdr  *nlh;
531 	struct netconfmsg *ncm;
532 	bool all = false;
533 
534 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
535 			flags);
536 	if (!nlh)
537 		return -EMSGSIZE;
538 
539 	if (type == NETCONFA_ALL)
540 		all = true;
541 
542 	ncm = nlmsg_data(nlh);
543 	ncm->ncm_family = AF_INET6;
544 
545 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
546 		goto nla_put_failure;
547 
548 	if (!devconf)
549 		goto out;
550 
551 	if ((all || type == NETCONFA_FORWARDING) &&
552 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
553 		goto nla_put_failure;
554 #ifdef CONFIG_IPV6_MROUTE
555 	if ((all || type == NETCONFA_MC_FORWARDING) &&
556 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
557 			atomic_read(&devconf->mc_forwarding)) < 0)
558 		goto nla_put_failure;
559 #endif
560 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
561 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
562 		goto nla_put_failure;
563 
564 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
565 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
566 			devconf->ignore_routes_with_linkdown) < 0)
567 		goto nla_put_failure;
568 
569 out:
570 	nlmsg_end(skb, nlh);
571 	return 0;
572 
573 nla_put_failure:
574 	nlmsg_cancel(skb, nlh);
575 	return -EMSGSIZE;
576 }
577 
578 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
579 				  int ifindex, struct ipv6_devconf *devconf)
580 {
581 	struct sk_buff *skb;
582 	int err = -ENOBUFS;
583 
584 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
585 	if (!skb)
586 		goto errout;
587 
588 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
589 					 event, 0, type);
590 	if (err < 0) {
591 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
592 		WARN_ON(err == -EMSGSIZE);
593 		kfree_skb(skb);
594 		goto errout;
595 	}
596 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
597 	return;
598 errout:
599 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
600 }
601 
602 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
603 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
604 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
605 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
606 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
607 };
608 
609 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
610 				       const struct nlmsghdr *nlh,
611 				       struct nlattr **tb,
612 				       struct netlink_ext_ack *extack)
613 {
614 	int i, err;
615 
616 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
617 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
618 		return -EINVAL;
619 	}
620 
621 	if (!netlink_strict_get_check(skb))
622 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
623 					      tb, NETCONFA_MAX,
624 					      devconf_ipv6_policy, extack);
625 
626 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
627 					    tb, NETCONFA_MAX,
628 					    devconf_ipv6_policy, extack);
629 	if (err)
630 		return err;
631 
632 	for (i = 0; i <= NETCONFA_MAX; i++) {
633 		if (!tb[i])
634 			continue;
635 
636 		switch (i) {
637 		case NETCONFA_IFINDEX:
638 			break;
639 		default:
640 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
641 			return -EINVAL;
642 		}
643 	}
644 
645 	return 0;
646 }
647 
648 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
649 				     struct nlmsghdr *nlh,
650 				     struct netlink_ext_ack *extack)
651 {
652 	struct net *net = sock_net(in_skb->sk);
653 	struct nlattr *tb[NETCONFA_MAX+1];
654 	struct inet6_dev *in6_dev = NULL;
655 	struct net_device *dev = NULL;
656 	struct sk_buff *skb;
657 	struct ipv6_devconf *devconf;
658 	int ifindex;
659 	int err;
660 
661 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
662 	if (err < 0)
663 		return err;
664 
665 	if (!tb[NETCONFA_IFINDEX])
666 		return -EINVAL;
667 
668 	err = -EINVAL;
669 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
670 	switch (ifindex) {
671 	case NETCONFA_IFINDEX_ALL:
672 		devconf = net->ipv6.devconf_all;
673 		break;
674 	case NETCONFA_IFINDEX_DEFAULT:
675 		devconf = net->ipv6.devconf_dflt;
676 		break;
677 	default:
678 		dev = dev_get_by_index(net, ifindex);
679 		if (!dev)
680 			return -EINVAL;
681 		in6_dev = in6_dev_get(dev);
682 		if (!in6_dev)
683 			goto errout;
684 		devconf = &in6_dev->cnf;
685 		break;
686 	}
687 
688 	err = -ENOBUFS;
689 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
690 	if (!skb)
691 		goto errout;
692 
693 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
694 					 NETLINK_CB(in_skb).portid,
695 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
696 					 NETCONFA_ALL);
697 	if (err < 0) {
698 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
699 		WARN_ON(err == -EMSGSIZE);
700 		kfree_skb(skb);
701 		goto errout;
702 	}
703 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
704 errout:
705 	if (in6_dev)
706 		in6_dev_put(in6_dev);
707 	dev_put(dev);
708 	return err;
709 }
710 
711 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
712 				      struct netlink_callback *cb)
713 {
714 	const struct nlmsghdr *nlh = cb->nlh;
715 	struct net *net = sock_net(skb->sk);
716 	int h, s_h;
717 	int idx, s_idx;
718 	struct net_device *dev;
719 	struct inet6_dev *idev;
720 	struct hlist_head *head;
721 
722 	if (cb->strict_check) {
723 		struct netlink_ext_ack *extack = cb->extack;
724 		struct netconfmsg *ncm;
725 
726 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
727 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
728 			return -EINVAL;
729 		}
730 
731 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
732 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
733 			return -EINVAL;
734 		}
735 	}
736 
737 	s_h = cb->args[0];
738 	s_idx = idx = cb->args[1];
739 
740 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
741 		idx = 0;
742 		head = &net->dev_index_head[h];
743 		rcu_read_lock();
744 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
745 			  net->dev_base_seq;
746 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
747 			if (idx < s_idx)
748 				goto cont;
749 			idev = __in6_dev_get(dev);
750 			if (!idev)
751 				goto cont;
752 
753 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
754 						       &idev->cnf,
755 						       NETLINK_CB(cb->skb).portid,
756 						       nlh->nlmsg_seq,
757 						       RTM_NEWNETCONF,
758 						       NLM_F_MULTI,
759 						       NETCONFA_ALL) < 0) {
760 				rcu_read_unlock();
761 				goto done;
762 			}
763 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
764 cont:
765 			idx++;
766 		}
767 		rcu_read_unlock();
768 	}
769 	if (h == NETDEV_HASHENTRIES) {
770 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
771 					       net->ipv6.devconf_all,
772 					       NETLINK_CB(cb->skb).portid,
773 					       nlh->nlmsg_seq,
774 					       RTM_NEWNETCONF, NLM_F_MULTI,
775 					       NETCONFA_ALL) < 0)
776 			goto done;
777 		else
778 			h++;
779 	}
780 	if (h == NETDEV_HASHENTRIES + 1) {
781 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
782 					       net->ipv6.devconf_dflt,
783 					       NETLINK_CB(cb->skb).portid,
784 					       nlh->nlmsg_seq,
785 					       RTM_NEWNETCONF, NLM_F_MULTI,
786 					       NETCONFA_ALL) < 0)
787 			goto done;
788 		else
789 			h++;
790 	}
791 done:
792 	cb->args[0] = h;
793 	cb->args[1] = idx;
794 
795 	return skb->len;
796 }
797 
798 #ifdef CONFIG_SYSCTL
799 static void dev_forward_change(struct inet6_dev *idev)
800 {
801 	struct net_device *dev;
802 	struct inet6_ifaddr *ifa;
803 	LIST_HEAD(tmp_addr_list);
804 
805 	if (!idev)
806 		return;
807 	dev = idev->dev;
808 	if (idev->cnf.forwarding)
809 		dev_disable_lro(dev);
810 	if (dev->flags & IFF_MULTICAST) {
811 		if (idev->cnf.forwarding) {
812 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
813 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
814 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
815 		} else {
816 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
817 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
818 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
819 		}
820 	}
821 
822 	read_lock_bh(&idev->lock);
823 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
824 		if (ifa->flags&IFA_F_TENTATIVE)
825 			continue;
826 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
827 	}
828 	read_unlock_bh(&idev->lock);
829 
830 	while (!list_empty(&tmp_addr_list)) {
831 		ifa = list_first_entry(&tmp_addr_list,
832 				       struct inet6_ifaddr, if_list_aux);
833 		list_del(&ifa->if_list_aux);
834 		if (idev->cnf.forwarding)
835 			addrconf_join_anycast(ifa);
836 		else
837 			addrconf_leave_anycast(ifa);
838 	}
839 
840 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
841 				     NETCONFA_FORWARDING,
842 				     dev->ifindex, &idev->cnf);
843 }
844 
845 
846 static void addrconf_forward_change(struct net *net, __s32 newf)
847 {
848 	struct net_device *dev;
849 	struct inet6_dev *idev;
850 
851 	for_each_netdev(net, dev) {
852 		idev = __in6_dev_get(dev);
853 		if (idev) {
854 			int changed = (!idev->cnf.forwarding) ^ (!newf);
855 			idev->cnf.forwarding = newf;
856 			if (changed)
857 				dev_forward_change(idev);
858 		}
859 	}
860 }
861 
862 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
863 {
864 	struct net *net;
865 	int old;
866 
867 	if (!rtnl_trylock())
868 		return restart_syscall();
869 
870 	net = (struct net *)table->extra2;
871 	old = *p;
872 	*p = newf;
873 
874 	if (p == &net->ipv6.devconf_dflt->forwarding) {
875 		if ((!newf) ^ (!old))
876 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
877 						     NETCONFA_FORWARDING,
878 						     NETCONFA_IFINDEX_DEFAULT,
879 						     net->ipv6.devconf_dflt);
880 		rtnl_unlock();
881 		return 0;
882 	}
883 
884 	if (p == &net->ipv6.devconf_all->forwarding) {
885 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
886 
887 		net->ipv6.devconf_dflt->forwarding = newf;
888 		if ((!newf) ^ (!old_dflt))
889 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
890 						     NETCONFA_FORWARDING,
891 						     NETCONFA_IFINDEX_DEFAULT,
892 						     net->ipv6.devconf_dflt);
893 
894 		addrconf_forward_change(net, newf);
895 		if ((!newf) ^ (!old))
896 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
897 						     NETCONFA_FORWARDING,
898 						     NETCONFA_IFINDEX_ALL,
899 						     net->ipv6.devconf_all);
900 	} else if ((!newf) ^ (!old))
901 		dev_forward_change((struct inet6_dev *)table->extra1);
902 	rtnl_unlock();
903 
904 	if (newf)
905 		rt6_purge_dflt_routers(net);
906 	return 1;
907 }
908 
909 static void addrconf_linkdown_change(struct net *net, __s32 newf)
910 {
911 	struct net_device *dev;
912 	struct inet6_dev *idev;
913 
914 	for_each_netdev(net, dev) {
915 		idev = __in6_dev_get(dev);
916 		if (idev) {
917 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
918 
919 			idev->cnf.ignore_routes_with_linkdown = newf;
920 			if (changed)
921 				inet6_netconf_notify_devconf(dev_net(dev),
922 							     RTM_NEWNETCONF,
923 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
924 							     dev->ifindex,
925 							     &idev->cnf);
926 		}
927 	}
928 }
929 
930 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
931 {
932 	struct net *net;
933 	int old;
934 
935 	if (!rtnl_trylock())
936 		return restart_syscall();
937 
938 	net = (struct net *)table->extra2;
939 	old = *p;
940 	*p = newf;
941 
942 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
943 		if ((!newf) ^ (!old))
944 			inet6_netconf_notify_devconf(net,
945 						     RTM_NEWNETCONF,
946 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
947 						     NETCONFA_IFINDEX_DEFAULT,
948 						     net->ipv6.devconf_dflt);
949 		rtnl_unlock();
950 		return 0;
951 	}
952 
953 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
954 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
955 		addrconf_linkdown_change(net, newf);
956 		if ((!newf) ^ (!old))
957 			inet6_netconf_notify_devconf(net,
958 						     RTM_NEWNETCONF,
959 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
960 						     NETCONFA_IFINDEX_ALL,
961 						     net->ipv6.devconf_all);
962 	}
963 	rtnl_unlock();
964 
965 	return 1;
966 }
967 
968 #endif
969 
970 /* Nobody refers to this ifaddr, destroy it */
971 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
972 {
973 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
974 
975 #ifdef NET_REFCNT_DEBUG
976 	pr_debug("%s\n", __func__);
977 #endif
978 
979 	in6_dev_put(ifp->idev);
980 
981 	if (cancel_delayed_work(&ifp->dad_work))
982 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
983 			  ifp);
984 
985 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
986 		pr_warn("Freeing alive inet6 address %p\n", ifp);
987 		return;
988 	}
989 
990 	kfree_rcu(ifp, rcu);
991 }
992 
993 static void
994 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
995 {
996 	struct list_head *p;
997 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
998 
999 	/*
1000 	 * Each device address list is sorted in order of scope -
1001 	 * global before linklocal.
1002 	 */
1003 	list_for_each(p, &idev->addr_list) {
1004 		struct inet6_ifaddr *ifa
1005 			= list_entry(p, struct inet6_ifaddr, if_list);
1006 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1007 			break;
1008 	}
1009 
1010 	list_add_tail_rcu(&ifp->if_list, p);
1011 }
1012 
1013 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1014 {
1015 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
1016 
1017 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1018 }
1019 
1020 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1021 			       struct net_device *dev, unsigned int hash)
1022 {
1023 	struct inet6_ifaddr *ifp;
1024 
1025 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1026 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1027 			if (!dev || ifp->idev->dev == dev)
1028 				return true;
1029 		}
1030 	}
1031 	return false;
1032 }
1033 
1034 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1035 {
1036 	struct net *net = dev_net(dev);
1037 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1038 	int err = 0;
1039 
1040 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1041 
1042 	/* Ignore adding duplicate addresses on an interface */
1043 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1044 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1045 		err = -EEXIST;
1046 	} else {
1047 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1048 	}
1049 
1050 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1051 
1052 	return err;
1053 }
1054 
1055 /* On success it returns ifp with increased reference count */
1056 
1057 static struct inet6_ifaddr *
1058 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1059 	      bool can_block, struct netlink_ext_ack *extack)
1060 {
1061 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1062 	int addr_type = ipv6_addr_type(cfg->pfx);
1063 	struct net *net = dev_net(idev->dev);
1064 	struct inet6_ifaddr *ifa = NULL;
1065 	struct fib6_info *f6i = NULL;
1066 	int err = 0;
1067 
1068 	if (addr_type == IPV6_ADDR_ANY) {
1069 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1070 		return ERR_PTR(-EADDRNOTAVAIL);
1071 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1072 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1073 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1074 		return ERR_PTR(-EADDRNOTAVAIL);
1075 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1076 		   !netif_is_l3_master(idev->dev) &&
1077 		   addr_type & IPV6_ADDR_LOOPBACK) {
1078 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1079 		return ERR_PTR(-EADDRNOTAVAIL);
1080 	}
1081 
1082 	if (idev->dead) {
1083 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1084 		err = -ENODEV;
1085 		goto out;
1086 	}
1087 
1088 	if (idev->cnf.disable_ipv6) {
1089 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1090 		err = -EACCES;
1091 		goto out;
1092 	}
1093 
1094 	/* validator notifier needs to be blocking;
1095 	 * do not call in atomic context
1096 	 */
1097 	if (can_block) {
1098 		struct in6_validator_info i6vi = {
1099 			.i6vi_addr = *cfg->pfx,
1100 			.i6vi_dev = idev,
1101 			.extack = extack,
1102 		};
1103 
1104 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1105 		err = notifier_to_errno(err);
1106 		if (err < 0)
1107 			goto out;
1108 	}
1109 
1110 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1111 	if (!ifa) {
1112 		err = -ENOBUFS;
1113 		goto out;
1114 	}
1115 
1116 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1117 	if (IS_ERR(f6i)) {
1118 		err = PTR_ERR(f6i);
1119 		f6i = NULL;
1120 		goto out;
1121 	}
1122 
1123 	neigh_parms_data_state_setall(idev->nd_parms);
1124 
1125 	ifa->addr = *cfg->pfx;
1126 	if (cfg->peer_pfx)
1127 		ifa->peer_addr = *cfg->peer_pfx;
1128 
1129 	spin_lock_init(&ifa->lock);
1130 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1131 	INIT_HLIST_NODE(&ifa->addr_lst);
1132 	ifa->scope = cfg->scope;
1133 	ifa->prefix_len = cfg->plen;
1134 	ifa->rt_priority = cfg->rt_priority;
1135 	ifa->flags = cfg->ifa_flags;
1136 	ifa->ifa_proto = cfg->ifa_proto;
1137 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1138 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1139 		ifa->flags |= IFA_F_TENTATIVE;
1140 	ifa->valid_lft = cfg->valid_lft;
1141 	ifa->prefered_lft = cfg->preferred_lft;
1142 	ifa->cstamp = ifa->tstamp = jiffies;
1143 	ifa->tokenized = false;
1144 
1145 	ifa->rt = f6i;
1146 
1147 	ifa->idev = idev;
1148 	in6_dev_hold(idev);
1149 
1150 	/* For caller */
1151 	refcount_set(&ifa->refcnt, 1);
1152 
1153 	rcu_read_lock();
1154 
1155 	err = ipv6_add_addr_hash(idev->dev, ifa);
1156 	if (err < 0) {
1157 		rcu_read_unlock();
1158 		goto out;
1159 	}
1160 
1161 	write_lock_bh(&idev->lock);
1162 
1163 	/* Add to inet6_dev unicast addr list. */
1164 	ipv6_link_dev_addr(idev, ifa);
1165 
1166 	if (ifa->flags&IFA_F_TEMPORARY) {
1167 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1168 		in6_ifa_hold(ifa);
1169 	}
1170 
1171 	in6_ifa_hold(ifa);
1172 	write_unlock_bh(&idev->lock);
1173 
1174 	rcu_read_unlock();
1175 
1176 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1177 out:
1178 	if (unlikely(err < 0)) {
1179 		fib6_info_release(f6i);
1180 
1181 		if (ifa) {
1182 			if (ifa->idev)
1183 				in6_dev_put(ifa->idev);
1184 			kfree(ifa);
1185 		}
1186 		ifa = ERR_PTR(err);
1187 	}
1188 
1189 	return ifa;
1190 }
1191 
1192 enum cleanup_prefix_rt_t {
1193 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1194 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1195 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1196 };
1197 
1198 /*
1199  * Check, whether the prefix for ifp would still need a prefix route
1200  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1201  * constants.
1202  *
1203  * 1) we don't purge prefix if address was not permanent.
1204  *    prefix is managed by its own lifetime.
1205  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1206  * 3) if there are no addresses, delete prefix.
1207  * 4) if there are still other permanent address(es),
1208  *    corresponding prefix is still permanent.
1209  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1210  *    don't purge the prefix, assume user space is managing it.
1211  * 6) otherwise, update prefix lifetime to the
1212  *    longest valid lifetime among the corresponding
1213  *    addresses on the device.
1214  *    Note: subsequent RA will update lifetime.
1215  **/
1216 static enum cleanup_prefix_rt_t
1217 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1218 {
1219 	struct inet6_ifaddr *ifa;
1220 	struct inet6_dev *idev = ifp->idev;
1221 	unsigned long lifetime;
1222 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1223 
1224 	*expires = jiffies;
1225 
1226 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1227 		if (ifa == ifp)
1228 			continue;
1229 		if (ifa->prefix_len != ifp->prefix_len ||
1230 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1231 				       ifp->prefix_len))
1232 			continue;
1233 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1234 			return CLEANUP_PREFIX_RT_NOP;
1235 
1236 		action = CLEANUP_PREFIX_RT_EXPIRE;
1237 
1238 		spin_lock(&ifa->lock);
1239 
1240 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1241 		/*
1242 		 * Note: Because this address is
1243 		 * not permanent, lifetime <
1244 		 * LONG_MAX / HZ here.
1245 		 */
1246 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1247 			*expires = ifa->tstamp + lifetime * HZ;
1248 		spin_unlock(&ifa->lock);
1249 	}
1250 
1251 	return action;
1252 }
1253 
1254 static void
1255 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1256 		     bool del_rt, bool del_peer)
1257 {
1258 	struct fib6_info *f6i;
1259 
1260 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1261 					ifp->prefix_len,
1262 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1263 	if (f6i) {
1264 		if (del_rt)
1265 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1266 		else {
1267 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1268 				fib6_set_expires(f6i, expires);
1269 			fib6_info_release(f6i);
1270 		}
1271 	}
1272 }
1273 
1274 
1275 /* This function wants to get referenced ifp and releases it before return */
1276 
1277 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1278 {
1279 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1280 	struct net *net = dev_net(ifp->idev->dev);
1281 	unsigned long expires;
1282 	int state;
1283 
1284 	ASSERT_RTNL();
1285 
1286 	spin_lock_bh(&ifp->lock);
1287 	state = ifp->state;
1288 	ifp->state = INET6_IFADDR_STATE_DEAD;
1289 	spin_unlock_bh(&ifp->lock);
1290 
1291 	if (state == INET6_IFADDR_STATE_DEAD)
1292 		goto out;
1293 
1294 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1295 	hlist_del_init_rcu(&ifp->addr_lst);
1296 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1297 
1298 	write_lock_bh(&ifp->idev->lock);
1299 
1300 	if (ifp->flags&IFA_F_TEMPORARY) {
1301 		list_del(&ifp->tmp_list);
1302 		if (ifp->ifpub) {
1303 			in6_ifa_put(ifp->ifpub);
1304 			ifp->ifpub = NULL;
1305 		}
1306 		__in6_ifa_put(ifp);
1307 	}
1308 
1309 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1310 		action = check_cleanup_prefix_route(ifp, &expires);
1311 
1312 	list_del_rcu(&ifp->if_list);
1313 	__in6_ifa_put(ifp);
1314 
1315 	write_unlock_bh(&ifp->idev->lock);
1316 
1317 	addrconf_del_dad_work(ifp);
1318 
1319 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1320 
1321 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1322 
1323 	if (action != CLEANUP_PREFIX_RT_NOP) {
1324 		cleanup_prefix_route(ifp, expires,
1325 			action == CLEANUP_PREFIX_RT_DEL, false);
1326 	}
1327 
1328 	/* clean up prefsrc entries */
1329 	rt6_remove_prefsrc(ifp);
1330 out:
1331 	in6_ifa_put(ifp);
1332 }
1333 
1334 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1335 {
1336 	struct inet6_dev *idev = ifp->idev;
1337 	unsigned long tmp_tstamp, age;
1338 	unsigned long regen_advance;
1339 	unsigned long now = jiffies;
1340 	s32 cnf_temp_preferred_lft;
1341 	struct inet6_ifaddr *ift;
1342 	struct ifa6_config cfg;
1343 	long max_desync_factor;
1344 	struct in6_addr addr;
1345 	int ret = 0;
1346 
1347 	write_lock_bh(&idev->lock);
1348 
1349 retry:
1350 	in6_dev_hold(idev);
1351 	if (idev->cnf.use_tempaddr <= 0) {
1352 		write_unlock_bh(&idev->lock);
1353 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1354 		in6_dev_put(idev);
1355 		ret = -1;
1356 		goto out;
1357 	}
1358 	spin_lock_bh(&ifp->lock);
1359 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1360 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1361 		spin_unlock_bh(&ifp->lock);
1362 		write_unlock_bh(&idev->lock);
1363 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1364 			__func__);
1365 		in6_dev_put(idev);
1366 		ret = -1;
1367 		goto out;
1368 	}
1369 	in6_ifa_hold(ifp);
1370 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1371 	ipv6_gen_rnd_iid(&addr);
1372 
1373 	age = (now - ifp->tstamp) / HZ;
1374 
1375 	regen_advance = idev->cnf.regen_max_retry *
1376 			idev->cnf.dad_transmits *
1377 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1378 
1379 	/* recalculate max_desync_factor each time and update
1380 	 * idev->desync_factor if it's larger
1381 	 */
1382 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1383 	max_desync_factor = min_t(long,
1384 				  idev->cnf.max_desync_factor,
1385 				  cnf_temp_preferred_lft - regen_advance);
1386 
1387 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1388 		if (max_desync_factor > 0) {
1389 			get_random_bytes(&idev->desync_factor,
1390 					 sizeof(idev->desync_factor));
1391 			idev->desync_factor %= max_desync_factor;
1392 		} else {
1393 			idev->desync_factor = 0;
1394 		}
1395 	}
1396 
1397 	memset(&cfg, 0, sizeof(cfg));
1398 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1399 			      idev->cnf.temp_valid_lft + age);
1400 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1401 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1402 
1403 	cfg.plen = ifp->prefix_len;
1404 	tmp_tstamp = ifp->tstamp;
1405 	spin_unlock_bh(&ifp->lock);
1406 
1407 	write_unlock_bh(&idev->lock);
1408 
1409 	/* A temporary address is created only if this calculated Preferred
1410 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1411 	 * an implementation must not create a temporary address with a zero
1412 	 * Preferred Lifetime.
1413 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1414 	 * temporary addresses being generated.
1415 	 */
1416 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1417 	if (cfg.preferred_lft <= regen_advance + age) {
1418 		in6_ifa_put(ifp);
1419 		in6_dev_put(idev);
1420 		ret = -1;
1421 		goto out;
1422 	}
1423 
1424 	cfg.ifa_flags = IFA_F_TEMPORARY;
1425 	/* set in addrconf_prefix_rcv() */
1426 	if (ifp->flags & IFA_F_OPTIMISTIC)
1427 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1428 
1429 	cfg.pfx = &addr;
1430 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1431 
1432 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1433 	if (IS_ERR(ift)) {
1434 		in6_ifa_put(ifp);
1435 		in6_dev_put(idev);
1436 		pr_info("%s: retry temporary address regeneration\n", __func__);
1437 		write_lock_bh(&idev->lock);
1438 		goto retry;
1439 	}
1440 
1441 	spin_lock_bh(&ift->lock);
1442 	ift->ifpub = ifp;
1443 	ift->cstamp = now;
1444 	ift->tstamp = tmp_tstamp;
1445 	spin_unlock_bh(&ift->lock);
1446 
1447 	addrconf_dad_start(ift);
1448 	in6_ifa_put(ift);
1449 	in6_dev_put(idev);
1450 out:
1451 	return ret;
1452 }
1453 
1454 /*
1455  *	Choose an appropriate source address (RFC3484)
1456  */
1457 enum {
1458 	IPV6_SADDR_RULE_INIT = 0,
1459 	IPV6_SADDR_RULE_LOCAL,
1460 	IPV6_SADDR_RULE_SCOPE,
1461 	IPV6_SADDR_RULE_PREFERRED,
1462 #ifdef CONFIG_IPV6_MIP6
1463 	IPV6_SADDR_RULE_HOA,
1464 #endif
1465 	IPV6_SADDR_RULE_OIF,
1466 	IPV6_SADDR_RULE_LABEL,
1467 	IPV6_SADDR_RULE_PRIVACY,
1468 	IPV6_SADDR_RULE_ORCHID,
1469 	IPV6_SADDR_RULE_PREFIX,
1470 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1471 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1472 #endif
1473 	IPV6_SADDR_RULE_MAX
1474 };
1475 
1476 struct ipv6_saddr_score {
1477 	int			rule;
1478 	int			addr_type;
1479 	struct inet6_ifaddr	*ifa;
1480 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1481 	int			scopedist;
1482 	int			matchlen;
1483 };
1484 
1485 struct ipv6_saddr_dst {
1486 	const struct in6_addr *addr;
1487 	int ifindex;
1488 	int scope;
1489 	int label;
1490 	unsigned int prefs;
1491 };
1492 
1493 static inline int ipv6_saddr_preferred(int type)
1494 {
1495 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1496 		return 1;
1497 	return 0;
1498 }
1499 
1500 static bool ipv6_use_optimistic_addr(struct net *net,
1501 				     struct inet6_dev *idev)
1502 {
1503 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1504 	if (!idev)
1505 		return false;
1506 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1507 		return false;
1508 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1509 		return false;
1510 
1511 	return true;
1512 #else
1513 	return false;
1514 #endif
1515 }
1516 
1517 static bool ipv6_allow_optimistic_dad(struct net *net,
1518 				      struct inet6_dev *idev)
1519 {
1520 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1521 	if (!idev)
1522 		return false;
1523 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1524 		return false;
1525 
1526 	return true;
1527 #else
1528 	return false;
1529 #endif
1530 }
1531 
1532 static int ipv6_get_saddr_eval(struct net *net,
1533 			       struct ipv6_saddr_score *score,
1534 			       struct ipv6_saddr_dst *dst,
1535 			       int i)
1536 {
1537 	int ret;
1538 
1539 	if (i <= score->rule) {
1540 		switch (i) {
1541 		case IPV6_SADDR_RULE_SCOPE:
1542 			ret = score->scopedist;
1543 			break;
1544 		case IPV6_SADDR_RULE_PREFIX:
1545 			ret = score->matchlen;
1546 			break;
1547 		default:
1548 			ret = !!test_bit(i, score->scorebits);
1549 		}
1550 		goto out;
1551 	}
1552 
1553 	switch (i) {
1554 	case IPV6_SADDR_RULE_INIT:
1555 		/* Rule 0: remember if hiscore is not ready yet */
1556 		ret = !!score->ifa;
1557 		break;
1558 	case IPV6_SADDR_RULE_LOCAL:
1559 		/* Rule 1: Prefer same address */
1560 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1561 		break;
1562 	case IPV6_SADDR_RULE_SCOPE:
1563 		/* Rule 2: Prefer appropriate scope
1564 		 *
1565 		 *      ret
1566 		 *       ^
1567 		 *    -1 |  d 15
1568 		 *    ---+--+-+---> scope
1569 		 *       |
1570 		 *       |             d is scope of the destination.
1571 		 *  B-d  |  \
1572 		 *       |   \      <- smaller scope is better if
1573 		 *  B-15 |    \        if scope is enough for destination.
1574 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1575 		 * d-C-1 | /
1576 		 *       |/         <- greater is better
1577 		 *   -C  /             if scope is not enough for destination.
1578 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1579 		 *
1580 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1581 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1582 		 * Assume B = 0 and we get C > 29.
1583 		 */
1584 		ret = __ipv6_addr_src_scope(score->addr_type);
1585 		if (ret >= dst->scope)
1586 			ret = -ret;
1587 		else
1588 			ret -= 128;	/* 30 is enough */
1589 		score->scopedist = ret;
1590 		break;
1591 	case IPV6_SADDR_RULE_PREFERRED:
1592 	    {
1593 		/* Rule 3: Avoid deprecated and optimistic addresses */
1594 		u8 avoid = IFA_F_DEPRECATED;
1595 
1596 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1597 			avoid |= IFA_F_OPTIMISTIC;
1598 		ret = ipv6_saddr_preferred(score->addr_type) ||
1599 		      !(score->ifa->flags & avoid);
1600 		break;
1601 	    }
1602 #ifdef CONFIG_IPV6_MIP6
1603 	case IPV6_SADDR_RULE_HOA:
1604 	    {
1605 		/* Rule 4: Prefer home address */
1606 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1607 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1608 		break;
1609 	    }
1610 #endif
1611 	case IPV6_SADDR_RULE_OIF:
1612 		/* Rule 5: Prefer outgoing interface */
1613 		ret = (!dst->ifindex ||
1614 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1615 		break;
1616 	case IPV6_SADDR_RULE_LABEL:
1617 		/* Rule 6: Prefer matching label */
1618 		ret = ipv6_addr_label(net,
1619 				      &score->ifa->addr, score->addr_type,
1620 				      score->ifa->idev->dev->ifindex) == dst->label;
1621 		break;
1622 	case IPV6_SADDR_RULE_PRIVACY:
1623 	    {
1624 		/* Rule 7: Prefer public address
1625 		 * Note: prefer temporary address if use_tempaddr >= 2
1626 		 */
1627 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1628 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1629 				score->ifa->idev->cnf.use_tempaddr >= 2;
1630 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1631 		break;
1632 	    }
1633 	case IPV6_SADDR_RULE_ORCHID:
1634 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1635 		 *	    non-ORCHID vs non-ORCHID
1636 		 */
1637 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1638 			ipv6_addr_orchid(dst->addr));
1639 		break;
1640 	case IPV6_SADDR_RULE_PREFIX:
1641 		/* Rule 8: Use longest matching prefix */
1642 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1643 		if (ret > score->ifa->prefix_len)
1644 			ret = score->ifa->prefix_len;
1645 		score->matchlen = ret;
1646 		break;
1647 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1648 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1649 		/* Optimistic addresses still have lower precedence than other
1650 		 * preferred addresses.
1651 		 */
1652 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1653 		break;
1654 #endif
1655 	default:
1656 		ret = 0;
1657 	}
1658 
1659 	if (ret)
1660 		__set_bit(i, score->scorebits);
1661 	score->rule = i;
1662 out:
1663 	return ret;
1664 }
1665 
1666 static int __ipv6_dev_get_saddr(struct net *net,
1667 				struct ipv6_saddr_dst *dst,
1668 				struct inet6_dev *idev,
1669 				struct ipv6_saddr_score *scores,
1670 				int hiscore_idx)
1671 {
1672 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1673 
1674 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1675 		int i;
1676 
1677 		/*
1678 		 * - Tentative Address (RFC2462 section 5.4)
1679 		 *  - A tentative address is not considered
1680 		 *    "assigned to an interface" in the traditional
1681 		 *    sense, unless it is also flagged as optimistic.
1682 		 * - Candidate Source Address (section 4)
1683 		 *  - In any case, anycast addresses, multicast
1684 		 *    addresses, and the unspecified address MUST
1685 		 *    NOT be included in a candidate set.
1686 		 */
1687 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1688 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1689 			continue;
1690 
1691 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1692 
1693 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1694 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1695 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1696 					    idev->dev->name);
1697 			continue;
1698 		}
1699 
1700 		score->rule = -1;
1701 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1702 
1703 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1704 			int minihiscore, miniscore;
1705 
1706 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1707 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1708 
1709 			if (minihiscore > miniscore) {
1710 				if (i == IPV6_SADDR_RULE_SCOPE &&
1711 				    score->scopedist > 0) {
1712 					/*
1713 					 * special case:
1714 					 * each remaining entry
1715 					 * has too small (not enough)
1716 					 * scope, because ifa entries
1717 					 * are sorted by their scope
1718 					 * values.
1719 					 */
1720 					goto out;
1721 				}
1722 				break;
1723 			} else if (minihiscore < miniscore) {
1724 				swap(hiscore, score);
1725 				hiscore_idx = 1 - hiscore_idx;
1726 
1727 				/* restore our iterator */
1728 				score->ifa = hiscore->ifa;
1729 
1730 				break;
1731 			}
1732 		}
1733 	}
1734 out:
1735 	return hiscore_idx;
1736 }
1737 
1738 static int ipv6_get_saddr_master(struct net *net,
1739 				 const struct net_device *dst_dev,
1740 				 const struct net_device *master,
1741 				 struct ipv6_saddr_dst *dst,
1742 				 struct ipv6_saddr_score *scores,
1743 				 int hiscore_idx)
1744 {
1745 	struct inet6_dev *idev;
1746 
1747 	idev = __in6_dev_get(dst_dev);
1748 	if (idev)
1749 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1750 						   scores, hiscore_idx);
1751 
1752 	idev = __in6_dev_get(master);
1753 	if (idev)
1754 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1755 						   scores, hiscore_idx);
1756 
1757 	return hiscore_idx;
1758 }
1759 
1760 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1761 		       const struct in6_addr *daddr, unsigned int prefs,
1762 		       struct in6_addr *saddr)
1763 {
1764 	struct ipv6_saddr_score scores[2], *hiscore;
1765 	struct ipv6_saddr_dst dst;
1766 	struct inet6_dev *idev;
1767 	struct net_device *dev;
1768 	int dst_type;
1769 	bool use_oif_addr = false;
1770 	int hiscore_idx = 0;
1771 	int ret = 0;
1772 
1773 	dst_type = __ipv6_addr_type(daddr);
1774 	dst.addr = daddr;
1775 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1776 	dst.scope = __ipv6_addr_src_scope(dst_type);
1777 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1778 	dst.prefs = prefs;
1779 
1780 	scores[hiscore_idx].rule = -1;
1781 	scores[hiscore_idx].ifa = NULL;
1782 
1783 	rcu_read_lock();
1784 
1785 	/* Candidate Source Address (section 4)
1786 	 *  - multicast and link-local destination address,
1787 	 *    the set of candidate source address MUST only
1788 	 *    include addresses assigned to interfaces
1789 	 *    belonging to the same link as the outgoing
1790 	 *    interface.
1791 	 * (- For site-local destination addresses, the
1792 	 *    set of candidate source addresses MUST only
1793 	 *    include addresses assigned to interfaces
1794 	 *    belonging to the same site as the outgoing
1795 	 *    interface.)
1796 	 *  - "It is RECOMMENDED that the candidate source addresses
1797 	 *    be the set of unicast addresses assigned to the
1798 	 *    interface that will be used to send to the destination
1799 	 *    (the 'outgoing' interface)." (RFC 6724)
1800 	 */
1801 	if (dst_dev) {
1802 		idev = __in6_dev_get(dst_dev);
1803 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1804 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1805 		    (idev && idev->cnf.use_oif_addrs_only)) {
1806 			use_oif_addr = true;
1807 		}
1808 	}
1809 
1810 	if (use_oif_addr) {
1811 		if (idev)
1812 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1813 	} else {
1814 		const struct net_device *master;
1815 		int master_idx = 0;
1816 
1817 		/* if dst_dev exists and is enslaved to an L3 device, then
1818 		 * prefer addresses from dst_dev and then the master over
1819 		 * any other enslaved devices in the L3 domain.
1820 		 */
1821 		master = l3mdev_master_dev_rcu(dst_dev);
1822 		if (master) {
1823 			master_idx = master->ifindex;
1824 
1825 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1826 							    master, &dst,
1827 							    scores, hiscore_idx);
1828 
1829 			if (scores[hiscore_idx].ifa)
1830 				goto out;
1831 		}
1832 
1833 		for_each_netdev_rcu(net, dev) {
1834 			/* only consider addresses on devices in the
1835 			 * same L3 domain
1836 			 */
1837 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1838 				continue;
1839 			idev = __in6_dev_get(dev);
1840 			if (!idev)
1841 				continue;
1842 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1843 		}
1844 	}
1845 
1846 out:
1847 	hiscore = &scores[hiscore_idx];
1848 	if (!hiscore->ifa)
1849 		ret = -EADDRNOTAVAIL;
1850 	else
1851 		*saddr = hiscore->ifa->addr;
1852 
1853 	rcu_read_unlock();
1854 	return ret;
1855 }
1856 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1857 
1858 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1859 			      u32 banned_flags)
1860 {
1861 	struct inet6_ifaddr *ifp;
1862 	int err = -EADDRNOTAVAIL;
1863 
1864 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1865 		if (ifp->scope > IFA_LINK)
1866 			break;
1867 		if (ifp->scope == IFA_LINK &&
1868 		    !(ifp->flags & banned_flags)) {
1869 			*addr = ifp->addr;
1870 			err = 0;
1871 			break;
1872 		}
1873 	}
1874 	return err;
1875 }
1876 
1877 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1878 		    u32 banned_flags)
1879 {
1880 	struct inet6_dev *idev;
1881 	int err = -EADDRNOTAVAIL;
1882 
1883 	rcu_read_lock();
1884 	idev = __in6_dev_get(dev);
1885 	if (idev) {
1886 		read_lock_bh(&idev->lock);
1887 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1888 		read_unlock_bh(&idev->lock);
1889 	}
1890 	rcu_read_unlock();
1891 	return err;
1892 }
1893 
1894 static int ipv6_count_addresses(const struct inet6_dev *idev)
1895 {
1896 	const struct inet6_ifaddr *ifp;
1897 	int cnt = 0;
1898 
1899 	rcu_read_lock();
1900 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1901 		cnt++;
1902 	rcu_read_unlock();
1903 	return cnt;
1904 }
1905 
1906 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1907 		  const struct net_device *dev, int strict)
1908 {
1909 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1910 				       strict, IFA_F_TENTATIVE);
1911 }
1912 EXPORT_SYMBOL(ipv6_chk_addr);
1913 
1914 /* device argument is used to find the L3 domain of interest. If
1915  * skip_dev_check is set, then the ifp device is not checked against
1916  * the passed in dev argument. So the 2 cases for addresses checks are:
1917  *   1. does the address exist in the L3 domain that dev is part of
1918  *      (skip_dev_check = true), or
1919  *
1920  *   2. does the address exist on the specific device
1921  *      (skip_dev_check = false)
1922  */
1923 static struct net_device *
1924 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1925 			  const struct net_device *dev, bool skip_dev_check,
1926 			  int strict, u32 banned_flags)
1927 {
1928 	unsigned int hash = inet6_addr_hash(net, addr);
1929 	struct net_device *l3mdev, *ndev;
1930 	struct inet6_ifaddr *ifp;
1931 	u32 ifp_flags;
1932 
1933 	rcu_read_lock();
1934 
1935 	l3mdev = l3mdev_master_dev_rcu(dev);
1936 	if (skip_dev_check)
1937 		dev = NULL;
1938 
1939 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1940 		ndev = ifp->idev->dev;
1941 
1942 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1943 			continue;
1944 
1945 		/* Decouple optimistic from tentative for evaluation here.
1946 		 * Ban optimistic addresses explicitly, when required.
1947 		 */
1948 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1949 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1950 			    : ifp->flags;
1951 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1952 		    !(ifp_flags&banned_flags) &&
1953 		    (!dev || ndev == dev ||
1954 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1955 			rcu_read_unlock();
1956 			return ndev;
1957 		}
1958 	}
1959 
1960 	rcu_read_unlock();
1961 	return NULL;
1962 }
1963 
1964 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1965 			    const struct net_device *dev, bool skip_dev_check,
1966 			    int strict, u32 banned_flags)
1967 {
1968 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1969 					 strict, banned_flags) ? 1 : 0;
1970 }
1971 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1972 
1973 
1974 /* Compares an address/prefix_len with addresses on device @dev.
1975  * If one is found it returns true.
1976  */
1977 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1978 	const unsigned int prefix_len, struct net_device *dev)
1979 {
1980 	const struct inet6_ifaddr *ifa;
1981 	const struct inet6_dev *idev;
1982 	bool ret = false;
1983 
1984 	rcu_read_lock();
1985 	idev = __in6_dev_get(dev);
1986 	if (idev) {
1987 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1988 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1989 			if (ret)
1990 				break;
1991 		}
1992 	}
1993 	rcu_read_unlock();
1994 
1995 	return ret;
1996 }
1997 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1998 
1999 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2000 {
2001 	const struct inet6_ifaddr *ifa;
2002 	const struct inet6_dev *idev;
2003 	int	onlink;
2004 
2005 	onlink = 0;
2006 	rcu_read_lock();
2007 	idev = __in6_dev_get(dev);
2008 	if (idev) {
2009 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2010 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2011 						   ifa->prefix_len);
2012 			if (onlink)
2013 				break;
2014 		}
2015 	}
2016 	rcu_read_unlock();
2017 	return onlink;
2018 }
2019 EXPORT_SYMBOL(ipv6_chk_prefix);
2020 
2021 /**
2022  * ipv6_dev_find - find the first device with a given source address.
2023  * @net: the net namespace
2024  * @addr: the source address
2025  * @dev: used to find the L3 domain of interest
2026  *
2027  * The caller should be protected by RCU, or RTNL.
2028  */
2029 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2030 				 struct net_device *dev)
2031 {
2032 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2033 					 IFA_F_TENTATIVE);
2034 }
2035 EXPORT_SYMBOL(ipv6_dev_find);
2036 
2037 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2038 				     struct net_device *dev, int strict)
2039 {
2040 	unsigned int hash = inet6_addr_hash(net, addr);
2041 	struct inet6_ifaddr *ifp, *result = NULL;
2042 
2043 	rcu_read_lock();
2044 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2045 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2046 			if (!dev || ifp->idev->dev == dev ||
2047 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2048 				result = ifp;
2049 				in6_ifa_hold(ifp);
2050 				break;
2051 			}
2052 		}
2053 	}
2054 	rcu_read_unlock();
2055 
2056 	return result;
2057 }
2058 
2059 /* Gets referenced address, destroys ifaddr */
2060 
2061 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2062 {
2063 	if (dad_failed)
2064 		ifp->flags |= IFA_F_DADFAILED;
2065 
2066 	if (ifp->flags&IFA_F_TEMPORARY) {
2067 		struct inet6_ifaddr *ifpub;
2068 		spin_lock_bh(&ifp->lock);
2069 		ifpub = ifp->ifpub;
2070 		if (ifpub) {
2071 			in6_ifa_hold(ifpub);
2072 			spin_unlock_bh(&ifp->lock);
2073 			ipv6_create_tempaddr(ifpub, true);
2074 			in6_ifa_put(ifpub);
2075 		} else {
2076 			spin_unlock_bh(&ifp->lock);
2077 		}
2078 		ipv6_del_addr(ifp);
2079 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2080 		spin_lock_bh(&ifp->lock);
2081 		addrconf_del_dad_work(ifp);
2082 		ifp->flags |= IFA_F_TENTATIVE;
2083 		if (dad_failed)
2084 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2085 		spin_unlock_bh(&ifp->lock);
2086 		if (dad_failed)
2087 			ipv6_ifa_notify(0, ifp);
2088 		in6_ifa_put(ifp);
2089 	} else {
2090 		ipv6_del_addr(ifp);
2091 	}
2092 }
2093 
2094 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2095 {
2096 	int err = -ENOENT;
2097 
2098 	spin_lock_bh(&ifp->lock);
2099 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2100 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2101 		err = 0;
2102 	}
2103 	spin_unlock_bh(&ifp->lock);
2104 
2105 	return err;
2106 }
2107 
2108 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2109 {
2110 	struct inet6_dev *idev = ifp->idev;
2111 	struct net *net = dev_net(idev->dev);
2112 
2113 	if (addrconf_dad_end(ifp)) {
2114 		in6_ifa_put(ifp);
2115 		return;
2116 	}
2117 
2118 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2119 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2120 
2121 	spin_lock_bh(&ifp->lock);
2122 
2123 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2124 		struct in6_addr new_addr;
2125 		struct inet6_ifaddr *ifp2;
2126 		int retries = ifp->stable_privacy_retry + 1;
2127 		struct ifa6_config cfg = {
2128 			.pfx = &new_addr,
2129 			.plen = ifp->prefix_len,
2130 			.ifa_flags = ifp->flags,
2131 			.valid_lft = ifp->valid_lft,
2132 			.preferred_lft = ifp->prefered_lft,
2133 			.scope = ifp->scope,
2134 		};
2135 
2136 		if (retries > net->ipv6.sysctl.idgen_retries) {
2137 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2138 					     ifp->idev->dev->name);
2139 			goto errdad;
2140 		}
2141 
2142 		new_addr = ifp->addr;
2143 		if (ipv6_generate_stable_address(&new_addr, retries,
2144 						 idev))
2145 			goto errdad;
2146 
2147 		spin_unlock_bh(&ifp->lock);
2148 
2149 		if (idev->cnf.max_addresses &&
2150 		    ipv6_count_addresses(idev) >=
2151 		    idev->cnf.max_addresses)
2152 			goto lock_errdad;
2153 
2154 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2155 				     ifp->idev->dev->name);
2156 
2157 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2158 		if (IS_ERR(ifp2))
2159 			goto lock_errdad;
2160 
2161 		spin_lock_bh(&ifp2->lock);
2162 		ifp2->stable_privacy_retry = retries;
2163 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2164 		spin_unlock_bh(&ifp2->lock);
2165 
2166 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2167 		in6_ifa_put(ifp2);
2168 lock_errdad:
2169 		spin_lock_bh(&ifp->lock);
2170 	}
2171 
2172 errdad:
2173 	/* transition from _POSTDAD to _ERRDAD */
2174 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2175 	spin_unlock_bh(&ifp->lock);
2176 
2177 	addrconf_mod_dad_work(ifp, 0);
2178 	in6_ifa_put(ifp);
2179 }
2180 
2181 /* Join to solicited addr multicast group.
2182  * caller must hold RTNL */
2183 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2184 {
2185 	struct in6_addr maddr;
2186 
2187 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2188 		return;
2189 
2190 	addrconf_addr_solict_mult(addr, &maddr);
2191 	ipv6_dev_mc_inc(dev, &maddr);
2192 }
2193 
2194 /* caller must hold RTNL */
2195 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2196 {
2197 	struct in6_addr maddr;
2198 
2199 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2200 		return;
2201 
2202 	addrconf_addr_solict_mult(addr, &maddr);
2203 	__ipv6_dev_mc_dec(idev, &maddr);
2204 }
2205 
2206 /* caller must hold RTNL */
2207 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2208 {
2209 	struct in6_addr addr;
2210 
2211 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2212 		return;
2213 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2214 	if (ipv6_addr_any(&addr))
2215 		return;
2216 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2217 }
2218 
2219 /* caller must hold RTNL */
2220 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2221 {
2222 	struct in6_addr addr;
2223 
2224 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2225 		return;
2226 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2227 	if (ipv6_addr_any(&addr))
2228 		return;
2229 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2230 }
2231 
2232 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2233 {
2234 	switch (dev->addr_len) {
2235 	case ETH_ALEN:
2236 		memcpy(eui, dev->dev_addr, 3);
2237 		eui[3] = 0xFF;
2238 		eui[4] = 0xFE;
2239 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2240 		break;
2241 	case EUI64_ADDR_LEN:
2242 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2243 		eui[0] ^= 2;
2244 		break;
2245 	default:
2246 		return -1;
2247 	}
2248 
2249 	return 0;
2250 }
2251 
2252 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2253 {
2254 	const union fwnet_hwaddr *ha;
2255 
2256 	if (dev->addr_len != FWNET_ALEN)
2257 		return -1;
2258 
2259 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2260 
2261 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2262 	eui[0] ^= 2;
2263 	return 0;
2264 }
2265 
2266 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2267 {
2268 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2269 	if (dev->addr_len != ARCNET_ALEN)
2270 		return -1;
2271 	memset(eui, 0, 7);
2272 	eui[7] = *(u8 *)dev->dev_addr;
2273 	return 0;
2274 }
2275 
2276 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2277 {
2278 	if (dev->addr_len != INFINIBAND_ALEN)
2279 		return -1;
2280 	memcpy(eui, dev->dev_addr + 12, 8);
2281 	eui[0] |= 2;
2282 	return 0;
2283 }
2284 
2285 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2286 {
2287 	if (addr == 0)
2288 		return -1;
2289 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2290 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2291 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2292 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2293 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2294 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2295 	eui[1] = 0;
2296 	eui[2] = 0x5E;
2297 	eui[3] = 0xFE;
2298 	memcpy(eui + 4, &addr, 4);
2299 	return 0;
2300 }
2301 
2302 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2303 {
2304 	if (dev->priv_flags & IFF_ISATAP)
2305 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2306 	return -1;
2307 }
2308 
2309 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2310 {
2311 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2312 }
2313 
2314 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2315 {
2316 	memcpy(eui, dev->perm_addr, 3);
2317 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2318 	eui[3] = 0xFF;
2319 	eui[4] = 0xFE;
2320 	eui[0] ^= 2;
2321 	return 0;
2322 }
2323 
2324 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2325 {
2326 	switch (dev->type) {
2327 	case ARPHRD_ETHER:
2328 	case ARPHRD_FDDI:
2329 		return addrconf_ifid_eui48(eui, dev);
2330 	case ARPHRD_ARCNET:
2331 		return addrconf_ifid_arcnet(eui, dev);
2332 	case ARPHRD_INFINIBAND:
2333 		return addrconf_ifid_infiniband(eui, dev);
2334 	case ARPHRD_SIT:
2335 		return addrconf_ifid_sit(eui, dev);
2336 	case ARPHRD_IPGRE:
2337 	case ARPHRD_TUNNEL:
2338 		return addrconf_ifid_gre(eui, dev);
2339 	case ARPHRD_6LOWPAN:
2340 		return addrconf_ifid_6lowpan(eui, dev);
2341 	case ARPHRD_IEEE1394:
2342 		return addrconf_ifid_ieee1394(eui, dev);
2343 	case ARPHRD_TUNNEL6:
2344 	case ARPHRD_IP6GRE:
2345 	case ARPHRD_RAWIP:
2346 		return addrconf_ifid_ip6tnl(eui, dev);
2347 	}
2348 	return -1;
2349 }
2350 
2351 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2352 {
2353 	int err = -1;
2354 	struct inet6_ifaddr *ifp;
2355 
2356 	read_lock_bh(&idev->lock);
2357 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2358 		if (ifp->scope > IFA_LINK)
2359 			break;
2360 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2361 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2362 			err = 0;
2363 			break;
2364 		}
2365 	}
2366 	read_unlock_bh(&idev->lock);
2367 	return err;
2368 }
2369 
2370 /* Generation of a randomized Interface Identifier
2371  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2372  */
2373 
2374 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2375 {
2376 regen:
2377 	get_random_bytes(&addr->s6_addr[8], 8);
2378 
2379 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2380 	 * check if generated address is not inappropriate:
2381 	 *
2382 	 * - Reserved IPv6 Interface Identifiers
2383 	 * - XXX: already assigned to an address on the device
2384 	 */
2385 
2386 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2387 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2388 		goto regen;
2389 
2390 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2391 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2392 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2393 	 */
2394 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2395 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2396 		goto regen;
2397 
2398 	/* Reserved subnet anycast addresses */
2399 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2400 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2401 		goto regen;
2402 }
2403 
2404 /*
2405  *	Add prefix route.
2406  */
2407 
2408 static void
2409 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2410 		      struct net_device *dev, unsigned long expires,
2411 		      u32 flags, gfp_t gfp_flags)
2412 {
2413 	struct fib6_config cfg = {
2414 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2415 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2416 		.fc_ifindex = dev->ifindex,
2417 		.fc_expires = expires,
2418 		.fc_dst_len = plen,
2419 		.fc_flags = RTF_UP | flags,
2420 		.fc_nlinfo.nl_net = dev_net(dev),
2421 		.fc_protocol = RTPROT_KERNEL,
2422 		.fc_type = RTN_UNICAST,
2423 	};
2424 
2425 	cfg.fc_dst = *pfx;
2426 
2427 	/* Prevent useless cloning on PtP SIT.
2428 	   This thing is done here expecting that the whole
2429 	   class of non-broadcast devices need not cloning.
2430 	 */
2431 #if IS_ENABLED(CONFIG_IPV6_SIT)
2432 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2433 		cfg.fc_flags |= RTF_NONEXTHOP;
2434 #endif
2435 
2436 	ip6_route_add(&cfg, gfp_flags, NULL);
2437 }
2438 
2439 
2440 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2441 						  int plen,
2442 						  const struct net_device *dev,
2443 						  u32 flags, u32 noflags,
2444 						  bool no_gw)
2445 {
2446 	struct fib6_node *fn;
2447 	struct fib6_info *rt = NULL;
2448 	struct fib6_table *table;
2449 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2450 
2451 	table = fib6_get_table(dev_net(dev), tb_id);
2452 	if (!table)
2453 		return NULL;
2454 
2455 	rcu_read_lock();
2456 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2457 	if (!fn)
2458 		goto out;
2459 
2460 	for_each_fib6_node_rt_rcu(fn) {
2461 		/* prefix routes only use builtin fib6_nh */
2462 		if (rt->nh)
2463 			continue;
2464 
2465 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2466 			continue;
2467 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2468 			continue;
2469 		if ((rt->fib6_flags & flags) != flags)
2470 			continue;
2471 		if ((rt->fib6_flags & noflags) != 0)
2472 			continue;
2473 		if (!fib6_info_hold_safe(rt))
2474 			continue;
2475 		break;
2476 	}
2477 out:
2478 	rcu_read_unlock();
2479 	return rt;
2480 }
2481 
2482 
2483 /* Create "default" multicast route to the interface */
2484 
2485 static void addrconf_add_mroute(struct net_device *dev)
2486 {
2487 	struct fib6_config cfg = {
2488 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2489 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2490 		.fc_ifindex = dev->ifindex,
2491 		.fc_dst_len = 8,
2492 		.fc_flags = RTF_UP,
2493 		.fc_type = RTN_MULTICAST,
2494 		.fc_nlinfo.nl_net = dev_net(dev),
2495 		.fc_protocol = RTPROT_KERNEL,
2496 	};
2497 
2498 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2499 
2500 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2501 }
2502 
2503 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2504 {
2505 	struct inet6_dev *idev;
2506 
2507 	ASSERT_RTNL();
2508 
2509 	idev = ipv6_find_idev(dev);
2510 	if (IS_ERR(idev))
2511 		return idev;
2512 
2513 	if (idev->cnf.disable_ipv6)
2514 		return ERR_PTR(-EACCES);
2515 
2516 	/* Add default multicast route */
2517 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2518 		addrconf_add_mroute(dev);
2519 
2520 	return idev;
2521 }
2522 
2523 static void manage_tempaddrs(struct inet6_dev *idev,
2524 			     struct inet6_ifaddr *ifp,
2525 			     __u32 valid_lft, __u32 prefered_lft,
2526 			     bool create, unsigned long now)
2527 {
2528 	u32 flags;
2529 	struct inet6_ifaddr *ift;
2530 
2531 	read_lock_bh(&idev->lock);
2532 	/* update all temporary addresses in the list */
2533 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2534 		int age, max_valid, max_prefered;
2535 
2536 		if (ifp != ift->ifpub)
2537 			continue;
2538 
2539 		/* RFC 4941 section 3.3:
2540 		 * If a received option will extend the lifetime of a public
2541 		 * address, the lifetimes of temporary addresses should
2542 		 * be extended, subject to the overall constraint that no
2543 		 * temporary addresses should ever remain "valid" or "preferred"
2544 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2545 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2546 		 */
2547 		age = (now - ift->cstamp) / HZ;
2548 		max_valid = idev->cnf.temp_valid_lft - age;
2549 		if (max_valid < 0)
2550 			max_valid = 0;
2551 
2552 		max_prefered = idev->cnf.temp_prefered_lft -
2553 			       idev->desync_factor - age;
2554 		if (max_prefered < 0)
2555 			max_prefered = 0;
2556 
2557 		if (valid_lft > max_valid)
2558 			valid_lft = max_valid;
2559 
2560 		if (prefered_lft > max_prefered)
2561 			prefered_lft = max_prefered;
2562 
2563 		spin_lock(&ift->lock);
2564 		flags = ift->flags;
2565 		ift->valid_lft = valid_lft;
2566 		ift->prefered_lft = prefered_lft;
2567 		ift->tstamp = now;
2568 		if (prefered_lft > 0)
2569 			ift->flags &= ~IFA_F_DEPRECATED;
2570 
2571 		spin_unlock(&ift->lock);
2572 		if (!(flags&IFA_F_TENTATIVE))
2573 			ipv6_ifa_notify(0, ift);
2574 	}
2575 
2576 	/* Also create a temporary address if it's enabled but no temporary
2577 	 * address currently exists.
2578 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2579 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2580 	 * We don't want that to result in creating a new temporary ip address.
2581 	 */
2582 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2583 		create = true;
2584 
2585 	if (create && idev->cnf.use_tempaddr > 0) {
2586 		/* When a new public address is created as described
2587 		 * in [ADDRCONF], also create a new temporary address.
2588 		 */
2589 		read_unlock_bh(&idev->lock);
2590 		ipv6_create_tempaddr(ifp, false);
2591 	} else {
2592 		read_unlock_bh(&idev->lock);
2593 	}
2594 }
2595 
2596 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2597 {
2598 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2599 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2600 }
2601 
2602 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2603 				 const struct prefix_info *pinfo,
2604 				 struct inet6_dev *in6_dev,
2605 				 const struct in6_addr *addr, int addr_type,
2606 				 u32 addr_flags, bool sllao, bool tokenized,
2607 				 __u32 valid_lft, u32 prefered_lft)
2608 {
2609 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2610 	int create = 0, update_lft = 0;
2611 
2612 	if (!ifp && valid_lft) {
2613 		int max_addresses = in6_dev->cnf.max_addresses;
2614 		struct ifa6_config cfg = {
2615 			.pfx = addr,
2616 			.plen = pinfo->prefix_len,
2617 			.ifa_flags = addr_flags,
2618 			.valid_lft = valid_lft,
2619 			.preferred_lft = prefered_lft,
2620 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2621 			.ifa_proto = IFAPROT_KERNEL_RA
2622 		};
2623 
2624 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2625 		if ((net->ipv6.devconf_all->optimistic_dad ||
2626 		     in6_dev->cnf.optimistic_dad) &&
2627 		    !net->ipv6.devconf_all->forwarding && sllao)
2628 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2629 #endif
2630 
2631 		/* Do not allow to create too much of autoconfigured
2632 		 * addresses; this would be too easy way to crash kernel.
2633 		 */
2634 		if (!max_addresses ||
2635 		    ipv6_count_addresses(in6_dev) < max_addresses)
2636 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2637 
2638 		if (IS_ERR_OR_NULL(ifp))
2639 			return -1;
2640 
2641 		create = 1;
2642 		spin_lock_bh(&ifp->lock);
2643 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2644 		ifp->cstamp = jiffies;
2645 		ifp->tokenized = tokenized;
2646 		spin_unlock_bh(&ifp->lock);
2647 		addrconf_dad_start(ifp);
2648 	}
2649 
2650 	if (ifp) {
2651 		u32 flags;
2652 		unsigned long now;
2653 		u32 stored_lft;
2654 
2655 		/* update lifetime (RFC2462 5.5.3 e) */
2656 		spin_lock_bh(&ifp->lock);
2657 		now = jiffies;
2658 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2659 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2660 		else
2661 			stored_lft = 0;
2662 
2663 		/* RFC4862 Section 5.5.3e:
2664 		 * "Note that the preferred lifetime of the
2665 		 *  corresponding address is always reset to
2666 		 *  the Preferred Lifetime in the received
2667 		 *  Prefix Information option, regardless of
2668 		 *  whether the valid lifetime is also reset or
2669 		 *  ignored."
2670 		 *
2671 		 * So we should always update prefered_lft here.
2672 		 */
2673 		update_lft = !create && stored_lft;
2674 
2675 		if (update_lft && !in6_dev->cnf.ra_honor_pio_life) {
2676 			const u32 minimum_lft = min_t(u32,
2677 				stored_lft, MIN_VALID_LIFETIME);
2678 			valid_lft = max(valid_lft, minimum_lft);
2679 		}
2680 
2681 		if (update_lft) {
2682 			ifp->valid_lft = valid_lft;
2683 			ifp->prefered_lft = prefered_lft;
2684 			ifp->tstamp = now;
2685 			flags = ifp->flags;
2686 			ifp->flags &= ~IFA_F_DEPRECATED;
2687 			spin_unlock_bh(&ifp->lock);
2688 
2689 			if (!(flags&IFA_F_TENTATIVE))
2690 				ipv6_ifa_notify(0, ifp);
2691 		} else
2692 			spin_unlock_bh(&ifp->lock);
2693 
2694 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2695 				 create, now);
2696 
2697 		in6_ifa_put(ifp);
2698 		addrconf_verify(net);
2699 	}
2700 
2701 	return 0;
2702 }
2703 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2704 
2705 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2706 {
2707 	struct prefix_info *pinfo;
2708 	__u32 valid_lft;
2709 	__u32 prefered_lft;
2710 	int addr_type, err;
2711 	u32 addr_flags = 0;
2712 	struct inet6_dev *in6_dev;
2713 	struct net *net = dev_net(dev);
2714 
2715 	pinfo = (struct prefix_info *) opt;
2716 
2717 	if (len < sizeof(struct prefix_info)) {
2718 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2719 		return;
2720 	}
2721 
2722 	/*
2723 	 *	Validation checks ([ADDRCONF], page 19)
2724 	 */
2725 
2726 	addr_type = ipv6_addr_type(&pinfo->prefix);
2727 
2728 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2729 		return;
2730 
2731 	valid_lft = ntohl(pinfo->valid);
2732 	prefered_lft = ntohl(pinfo->prefered);
2733 
2734 	if (prefered_lft > valid_lft) {
2735 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2736 		return;
2737 	}
2738 
2739 	in6_dev = in6_dev_get(dev);
2740 
2741 	if (!in6_dev) {
2742 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2743 				    dev->name);
2744 		return;
2745 	}
2746 
2747 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2748 		goto put;
2749 
2750 	/*
2751 	 *	Two things going on here:
2752 	 *	1) Add routes for on-link prefixes
2753 	 *	2) Configure prefixes with the auto flag set
2754 	 */
2755 
2756 	if (pinfo->onlink) {
2757 		struct fib6_info *rt;
2758 		unsigned long rt_expires;
2759 
2760 		/* Avoid arithmetic overflow. Really, we could
2761 		 * save rt_expires in seconds, likely valid_lft,
2762 		 * but it would require division in fib gc, that it
2763 		 * not good.
2764 		 */
2765 		if (HZ > USER_HZ)
2766 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2767 		else
2768 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2769 
2770 		if (addrconf_finite_timeout(rt_expires))
2771 			rt_expires *= HZ;
2772 
2773 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2774 					       pinfo->prefix_len,
2775 					       dev,
2776 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2777 					       RTF_DEFAULT, true);
2778 
2779 		if (rt) {
2780 			/* Autoconf prefix route */
2781 			if (valid_lft == 0) {
2782 				ip6_del_rt(net, rt, false);
2783 				rt = NULL;
2784 			} else if (addrconf_finite_timeout(rt_expires)) {
2785 				/* not infinity */
2786 				fib6_set_expires(rt, jiffies + rt_expires);
2787 			} else {
2788 				fib6_clean_expires(rt);
2789 			}
2790 		} else if (valid_lft) {
2791 			clock_t expires = 0;
2792 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2793 			if (addrconf_finite_timeout(rt_expires)) {
2794 				/* not infinity */
2795 				flags |= RTF_EXPIRES;
2796 				expires = jiffies_to_clock_t(rt_expires);
2797 			}
2798 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2799 					      0, dev, expires, flags,
2800 					      GFP_ATOMIC);
2801 		}
2802 		fib6_info_release(rt);
2803 	}
2804 
2805 	/* Try to figure out our local address for this prefix */
2806 
2807 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2808 		struct in6_addr addr;
2809 		bool tokenized = false, dev_addr_generated = false;
2810 
2811 		if (pinfo->prefix_len == 64) {
2812 			memcpy(&addr, &pinfo->prefix, 8);
2813 
2814 			if (!ipv6_addr_any(&in6_dev->token)) {
2815 				read_lock_bh(&in6_dev->lock);
2816 				memcpy(addr.s6_addr + 8,
2817 				       in6_dev->token.s6_addr + 8, 8);
2818 				read_unlock_bh(&in6_dev->lock);
2819 				tokenized = true;
2820 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2821 				   !ipv6_generate_stable_address(&addr, 0,
2822 								 in6_dev)) {
2823 				addr_flags |= IFA_F_STABLE_PRIVACY;
2824 				goto ok;
2825 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2826 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2827 				goto put;
2828 			} else {
2829 				dev_addr_generated = true;
2830 			}
2831 			goto ok;
2832 		}
2833 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2834 				    pinfo->prefix_len);
2835 		goto put;
2836 
2837 ok:
2838 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2839 						   &addr, addr_type,
2840 						   addr_flags, sllao,
2841 						   tokenized, valid_lft,
2842 						   prefered_lft);
2843 		if (err)
2844 			goto put;
2845 
2846 		/* Ignore error case here because previous prefix add addr was
2847 		 * successful which will be notified.
2848 		 */
2849 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2850 					      addr_type, addr_flags, sllao,
2851 					      tokenized, valid_lft,
2852 					      prefered_lft,
2853 					      dev_addr_generated);
2854 	}
2855 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2856 put:
2857 	in6_dev_put(in6_dev);
2858 }
2859 
2860 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2861 		struct in6_ifreq *ireq)
2862 {
2863 	struct ip_tunnel_parm p = { };
2864 	int err;
2865 
2866 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2867 		return -EADDRNOTAVAIL;
2868 
2869 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2870 	p.iph.version = 4;
2871 	p.iph.ihl = 5;
2872 	p.iph.protocol = IPPROTO_IPV6;
2873 	p.iph.ttl = 64;
2874 
2875 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2876 		return -EOPNOTSUPP;
2877 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2878 	if (err)
2879 		return err;
2880 
2881 	dev = __dev_get_by_name(net, p.name);
2882 	if (!dev)
2883 		return -ENOBUFS;
2884 	return dev_open(dev, NULL);
2885 }
2886 
2887 /*
2888  *	Set destination address.
2889  *	Special case for SIT interfaces where we create a new "virtual"
2890  *	device.
2891  */
2892 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2893 {
2894 	struct net_device *dev;
2895 	struct in6_ifreq ireq;
2896 	int err = -ENODEV;
2897 
2898 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2899 		return -ENODEV;
2900 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2901 		return -EFAULT;
2902 
2903 	rtnl_lock();
2904 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2905 	if (dev && dev->type == ARPHRD_SIT)
2906 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2907 	rtnl_unlock();
2908 	return err;
2909 }
2910 
2911 static int ipv6_mc_config(struct sock *sk, bool join,
2912 			  const struct in6_addr *addr, int ifindex)
2913 {
2914 	int ret;
2915 
2916 	ASSERT_RTNL();
2917 
2918 	lock_sock(sk);
2919 	if (join)
2920 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2921 	else
2922 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2923 	release_sock(sk);
2924 
2925 	return ret;
2926 }
2927 
2928 /*
2929  *	Manual configuration of address on an interface
2930  */
2931 static int inet6_addr_add(struct net *net, int ifindex,
2932 			  struct ifa6_config *cfg,
2933 			  struct netlink_ext_ack *extack)
2934 {
2935 	struct inet6_ifaddr *ifp;
2936 	struct inet6_dev *idev;
2937 	struct net_device *dev;
2938 	unsigned long timeout;
2939 	clock_t expires;
2940 	u32 flags;
2941 
2942 	ASSERT_RTNL();
2943 
2944 	if (cfg->plen > 128) {
2945 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
2946 		return -EINVAL;
2947 	}
2948 
2949 	/* check the lifetime */
2950 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
2951 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
2952 		return -EINVAL;
2953 	}
2954 
2955 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
2956 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
2957 		return -EINVAL;
2958 	}
2959 
2960 	dev = __dev_get_by_index(net, ifindex);
2961 	if (!dev)
2962 		return -ENODEV;
2963 
2964 	idev = addrconf_add_dev(dev);
2965 	if (IS_ERR(idev)) {
2966 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
2967 		return PTR_ERR(idev);
2968 	}
2969 
2970 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2971 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2972 					 true, cfg->pfx, ifindex);
2973 
2974 		if (ret < 0) {
2975 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
2976 			return ret;
2977 		}
2978 	}
2979 
2980 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2981 
2982 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2983 	if (addrconf_finite_timeout(timeout)) {
2984 		expires = jiffies_to_clock_t(timeout * HZ);
2985 		cfg->valid_lft = timeout;
2986 		flags = RTF_EXPIRES;
2987 	} else {
2988 		expires = 0;
2989 		flags = 0;
2990 		cfg->ifa_flags |= IFA_F_PERMANENT;
2991 	}
2992 
2993 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2994 	if (addrconf_finite_timeout(timeout)) {
2995 		if (timeout == 0)
2996 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2997 		cfg->preferred_lft = timeout;
2998 	}
2999 
3000 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3001 	if (!IS_ERR(ifp)) {
3002 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3003 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3004 					      ifp->rt_priority, dev, expires,
3005 					      flags, GFP_KERNEL);
3006 		}
3007 
3008 		/* Send a netlink notification if DAD is enabled and
3009 		 * optimistic flag is not set
3010 		 */
3011 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3012 			ipv6_ifa_notify(0, ifp);
3013 		/*
3014 		 * Note that section 3.1 of RFC 4429 indicates
3015 		 * that the Optimistic flag should not be set for
3016 		 * manually configured addresses
3017 		 */
3018 		addrconf_dad_start(ifp);
3019 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3020 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3021 					 cfg->preferred_lft, true, jiffies);
3022 		in6_ifa_put(ifp);
3023 		addrconf_verify_rtnl(net);
3024 		return 0;
3025 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3026 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3027 			       cfg->pfx, ifindex);
3028 	}
3029 
3030 	return PTR_ERR(ifp);
3031 }
3032 
3033 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3034 			  const struct in6_addr *pfx, unsigned int plen,
3035 			  struct netlink_ext_ack *extack)
3036 {
3037 	struct inet6_ifaddr *ifp;
3038 	struct inet6_dev *idev;
3039 	struct net_device *dev;
3040 
3041 	if (plen > 128) {
3042 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3043 		return -EINVAL;
3044 	}
3045 
3046 	dev = __dev_get_by_index(net, ifindex);
3047 	if (!dev) {
3048 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3049 		return -ENODEV;
3050 	}
3051 
3052 	idev = __in6_dev_get(dev);
3053 	if (!idev) {
3054 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3055 		return -ENXIO;
3056 	}
3057 
3058 	read_lock_bh(&idev->lock);
3059 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3060 		if (ifp->prefix_len == plen &&
3061 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3062 			in6_ifa_hold(ifp);
3063 			read_unlock_bh(&idev->lock);
3064 
3065 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3066 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3067 				manage_tempaddrs(idev, ifp, 0, 0, false,
3068 						 jiffies);
3069 			ipv6_del_addr(ifp);
3070 			addrconf_verify_rtnl(net);
3071 			if (ipv6_addr_is_multicast(pfx)) {
3072 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3073 					       false, pfx, dev->ifindex);
3074 			}
3075 			return 0;
3076 		}
3077 	}
3078 	read_unlock_bh(&idev->lock);
3079 
3080 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3081 	return -EADDRNOTAVAIL;
3082 }
3083 
3084 
3085 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3086 {
3087 	struct ifa6_config cfg = {
3088 		.ifa_flags = IFA_F_PERMANENT,
3089 		.preferred_lft = INFINITY_LIFE_TIME,
3090 		.valid_lft = INFINITY_LIFE_TIME,
3091 	};
3092 	struct in6_ifreq ireq;
3093 	int err;
3094 
3095 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3096 		return -EPERM;
3097 
3098 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3099 		return -EFAULT;
3100 
3101 	cfg.pfx = &ireq.ifr6_addr;
3102 	cfg.plen = ireq.ifr6_prefixlen;
3103 
3104 	rtnl_lock();
3105 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3106 	rtnl_unlock();
3107 	return err;
3108 }
3109 
3110 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3111 {
3112 	struct in6_ifreq ireq;
3113 	int err;
3114 
3115 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3116 		return -EPERM;
3117 
3118 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3119 		return -EFAULT;
3120 
3121 	rtnl_lock();
3122 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3123 			     ireq.ifr6_prefixlen, NULL);
3124 	rtnl_unlock();
3125 	return err;
3126 }
3127 
3128 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3129 		     int plen, int scope, u8 proto)
3130 {
3131 	struct inet6_ifaddr *ifp;
3132 	struct ifa6_config cfg = {
3133 		.pfx = addr,
3134 		.plen = plen,
3135 		.ifa_flags = IFA_F_PERMANENT,
3136 		.valid_lft = INFINITY_LIFE_TIME,
3137 		.preferred_lft = INFINITY_LIFE_TIME,
3138 		.scope = scope,
3139 		.ifa_proto = proto
3140 	};
3141 
3142 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3143 	if (!IS_ERR(ifp)) {
3144 		spin_lock_bh(&ifp->lock);
3145 		ifp->flags &= ~IFA_F_TENTATIVE;
3146 		spin_unlock_bh(&ifp->lock);
3147 		rt_genid_bump_ipv6(dev_net(idev->dev));
3148 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3149 		in6_ifa_put(ifp);
3150 	}
3151 }
3152 
3153 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3154 static void add_v4_addrs(struct inet6_dev *idev)
3155 {
3156 	struct in6_addr addr;
3157 	struct net_device *dev;
3158 	struct net *net = dev_net(idev->dev);
3159 	int scope, plen, offset = 0;
3160 	u32 pflags = 0;
3161 
3162 	ASSERT_RTNL();
3163 
3164 	memset(&addr, 0, sizeof(struct in6_addr));
3165 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3166 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3167 		offset = sizeof(struct in6_addr) - 4;
3168 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3169 
3170 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3171 		scope = IPV6_ADDR_COMPATv4;
3172 		plen = 96;
3173 		pflags |= RTF_NONEXTHOP;
3174 	} else {
3175 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3176 			return;
3177 
3178 		addr.s6_addr32[0] = htonl(0xfe800000);
3179 		scope = IFA_LINK;
3180 		plen = 64;
3181 	}
3182 
3183 	if (addr.s6_addr32[3]) {
3184 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3185 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3186 				      GFP_KERNEL);
3187 		return;
3188 	}
3189 
3190 	for_each_netdev(net, dev) {
3191 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3192 		if (in_dev && (dev->flags & IFF_UP)) {
3193 			struct in_ifaddr *ifa;
3194 			int flag = scope;
3195 
3196 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3197 				addr.s6_addr32[3] = ifa->ifa_local;
3198 
3199 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3200 					continue;
3201 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3202 					if (idev->dev->flags&IFF_POINTOPOINT)
3203 						continue;
3204 					flag |= IFA_HOST;
3205 				}
3206 
3207 				add_addr(idev, &addr, plen, flag,
3208 					 IFAPROT_UNSPEC);
3209 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3210 						      0, pflags, GFP_KERNEL);
3211 			}
3212 		}
3213 	}
3214 }
3215 #endif
3216 
3217 static void init_loopback(struct net_device *dev)
3218 {
3219 	struct inet6_dev  *idev;
3220 
3221 	/* ::1 */
3222 
3223 	ASSERT_RTNL();
3224 
3225 	idev = ipv6_find_idev(dev);
3226 	if (IS_ERR(idev)) {
3227 		pr_debug("%s: add_dev failed\n", __func__);
3228 		return;
3229 	}
3230 
3231 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3232 }
3233 
3234 void addrconf_add_linklocal(struct inet6_dev *idev,
3235 			    const struct in6_addr *addr, u32 flags)
3236 {
3237 	struct ifa6_config cfg = {
3238 		.pfx = addr,
3239 		.plen = 64,
3240 		.ifa_flags = flags | IFA_F_PERMANENT,
3241 		.valid_lft = INFINITY_LIFE_TIME,
3242 		.preferred_lft = INFINITY_LIFE_TIME,
3243 		.scope = IFA_LINK,
3244 		.ifa_proto = IFAPROT_KERNEL_LL
3245 	};
3246 	struct inet6_ifaddr *ifp;
3247 
3248 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3249 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3250 	     idev->cnf.optimistic_dad) &&
3251 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3252 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3253 #endif
3254 
3255 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3256 	if (!IS_ERR(ifp)) {
3257 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3258 				      0, 0, GFP_ATOMIC);
3259 		addrconf_dad_start(ifp);
3260 		in6_ifa_put(ifp);
3261 	}
3262 }
3263 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3264 
3265 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3266 {
3267 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3268 		return true;
3269 
3270 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3271 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3272 		return true;
3273 
3274 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3275 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3276 		return true;
3277 
3278 	return false;
3279 }
3280 
3281 static int ipv6_generate_stable_address(struct in6_addr *address,
3282 					u8 dad_count,
3283 					const struct inet6_dev *idev)
3284 {
3285 	static DEFINE_SPINLOCK(lock);
3286 	static __u32 digest[SHA1_DIGEST_WORDS];
3287 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3288 
3289 	static union {
3290 		char __data[SHA1_BLOCK_SIZE];
3291 		struct {
3292 			struct in6_addr secret;
3293 			__be32 prefix[2];
3294 			unsigned char hwaddr[MAX_ADDR_LEN];
3295 			u8 dad_count;
3296 		} __packed;
3297 	} data;
3298 
3299 	struct in6_addr secret;
3300 	struct in6_addr temp;
3301 	struct net *net = dev_net(idev->dev);
3302 
3303 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3304 
3305 	if (idev->cnf.stable_secret.initialized)
3306 		secret = idev->cnf.stable_secret.secret;
3307 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3308 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3309 	else
3310 		return -1;
3311 
3312 retry:
3313 	spin_lock_bh(&lock);
3314 
3315 	sha1_init(digest);
3316 	memset(&data, 0, sizeof(data));
3317 	memset(workspace, 0, sizeof(workspace));
3318 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3319 	data.prefix[0] = address->s6_addr32[0];
3320 	data.prefix[1] = address->s6_addr32[1];
3321 	data.secret = secret;
3322 	data.dad_count = dad_count;
3323 
3324 	sha1_transform(digest, data.__data, workspace);
3325 
3326 	temp = *address;
3327 	temp.s6_addr32[2] = (__force __be32)digest[0];
3328 	temp.s6_addr32[3] = (__force __be32)digest[1];
3329 
3330 	spin_unlock_bh(&lock);
3331 
3332 	if (ipv6_reserved_interfaceid(temp)) {
3333 		dad_count++;
3334 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3335 			return -1;
3336 		goto retry;
3337 	}
3338 
3339 	*address = temp;
3340 	return 0;
3341 }
3342 
3343 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3344 {
3345 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3346 
3347 	if (s->initialized)
3348 		return;
3349 	s = &idev->cnf.stable_secret;
3350 	get_random_bytes(&s->secret, sizeof(s->secret));
3351 	s->initialized = true;
3352 }
3353 
3354 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3355 {
3356 	struct in6_addr addr;
3357 
3358 	/* no link local addresses on L3 master devices */
3359 	if (netif_is_l3_master(idev->dev))
3360 		return;
3361 
3362 	/* no link local addresses on devices flagged as slaves */
3363 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3364 		return;
3365 
3366 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3367 
3368 	switch (idev->cnf.addr_gen_mode) {
3369 	case IN6_ADDR_GEN_MODE_RANDOM:
3370 		ipv6_gen_mode_random_init(idev);
3371 		fallthrough;
3372 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3373 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3374 			addrconf_add_linklocal(idev, &addr,
3375 					       IFA_F_STABLE_PRIVACY);
3376 		else if (prefix_route)
3377 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3378 					      0, 0, GFP_KERNEL);
3379 		break;
3380 	case IN6_ADDR_GEN_MODE_EUI64:
3381 		/* addrconf_add_linklocal also adds a prefix_route and we
3382 		 * only need to care about prefix routes if ipv6_generate_eui64
3383 		 * couldn't generate one.
3384 		 */
3385 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3386 			addrconf_add_linklocal(idev, &addr, 0);
3387 		else if (prefix_route)
3388 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3389 					      0, 0, GFP_KERNEL);
3390 		break;
3391 	case IN6_ADDR_GEN_MODE_NONE:
3392 	default:
3393 		/* will not add any link local address */
3394 		break;
3395 	}
3396 }
3397 
3398 static void addrconf_dev_config(struct net_device *dev)
3399 {
3400 	struct inet6_dev *idev;
3401 
3402 	ASSERT_RTNL();
3403 
3404 	if ((dev->type != ARPHRD_ETHER) &&
3405 	    (dev->type != ARPHRD_FDDI) &&
3406 	    (dev->type != ARPHRD_ARCNET) &&
3407 	    (dev->type != ARPHRD_INFINIBAND) &&
3408 	    (dev->type != ARPHRD_IEEE1394) &&
3409 	    (dev->type != ARPHRD_TUNNEL6) &&
3410 	    (dev->type != ARPHRD_6LOWPAN) &&
3411 	    (dev->type != ARPHRD_TUNNEL) &&
3412 	    (dev->type != ARPHRD_NONE) &&
3413 	    (dev->type != ARPHRD_RAWIP)) {
3414 		/* Alas, we support only Ethernet autoconfiguration. */
3415 		idev = __in6_dev_get(dev);
3416 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3417 		    dev->flags & IFF_MULTICAST)
3418 			ipv6_mc_up(idev);
3419 		return;
3420 	}
3421 
3422 	idev = addrconf_add_dev(dev);
3423 	if (IS_ERR(idev))
3424 		return;
3425 
3426 	/* this device type has no EUI support */
3427 	if (dev->type == ARPHRD_NONE &&
3428 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3429 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3430 
3431 	addrconf_addr_gen(idev, false);
3432 }
3433 
3434 #if IS_ENABLED(CONFIG_IPV6_SIT)
3435 static void addrconf_sit_config(struct net_device *dev)
3436 {
3437 	struct inet6_dev *idev;
3438 
3439 	ASSERT_RTNL();
3440 
3441 	/*
3442 	 * Configure the tunnel with one of our IPv4
3443 	 * addresses... we should configure all of
3444 	 * our v4 addrs in the tunnel
3445 	 */
3446 
3447 	idev = ipv6_find_idev(dev);
3448 	if (IS_ERR(idev)) {
3449 		pr_debug("%s: add_dev failed\n", __func__);
3450 		return;
3451 	}
3452 
3453 	if (dev->priv_flags & IFF_ISATAP) {
3454 		addrconf_addr_gen(idev, false);
3455 		return;
3456 	}
3457 
3458 	add_v4_addrs(idev);
3459 
3460 	if (dev->flags&IFF_POINTOPOINT)
3461 		addrconf_add_mroute(dev);
3462 }
3463 #endif
3464 
3465 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3466 static void addrconf_gre_config(struct net_device *dev)
3467 {
3468 	struct inet6_dev *idev;
3469 
3470 	ASSERT_RTNL();
3471 
3472 	idev = ipv6_find_idev(dev);
3473 	if (IS_ERR(idev)) {
3474 		pr_debug("%s: add_dev failed\n", __func__);
3475 		return;
3476 	}
3477 
3478 	if (dev->type == ARPHRD_ETHER) {
3479 		addrconf_addr_gen(idev, true);
3480 		return;
3481 	}
3482 
3483 	add_v4_addrs(idev);
3484 
3485 	if (dev->flags & IFF_POINTOPOINT)
3486 		addrconf_add_mroute(dev);
3487 }
3488 #endif
3489 
3490 static void addrconf_init_auto_addrs(struct net_device *dev)
3491 {
3492 	switch (dev->type) {
3493 #if IS_ENABLED(CONFIG_IPV6_SIT)
3494 	case ARPHRD_SIT:
3495 		addrconf_sit_config(dev);
3496 		break;
3497 #endif
3498 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3499 	case ARPHRD_IP6GRE:
3500 	case ARPHRD_IPGRE:
3501 		addrconf_gre_config(dev);
3502 		break;
3503 #endif
3504 	case ARPHRD_LOOPBACK:
3505 		init_loopback(dev);
3506 		break;
3507 
3508 	default:
3509 		addrconf_dev_config(dev);
3510 		break;
3511 	}
3512 }
3513 
3514 static int fixup_permanent_addr(struct net *net,
3515 				struct inet6_dev *idev,
3516 				struct inet6_ifaddr *ifp)
3517 {
3518 	/* !fib6_node means the host route was removed from the
3519 	 * FIB, for example, if 'lo' device is taken down. In that
3520 	 * case regenerate the host route.
3521 	 */
3522 	if (!ifp->rt || !ifp->rt->fib6_node) {
3523 		struct fib6_info *f6i, *prev;
3524 
3525 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3526 					 GFP_ATOMIC, NULL);
3527 		if (IS_ERR(f6i))
3528 			return PTR_ERR(f6i);
3529 
3530 		/* ifp->rt can be accessed outside of rtnl */
3531 		spin_lock(&ifp->lock);
3532 		prev = ifp->rt;
3533 		ifp->rt = f6i;
3534 		spin_unlock(&ifp->lock);
3535 
3536 		fib6_info_release(prev);
3537 	}
3538 
3539 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3540 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3541 				      ifp->rt_priority, idev->dev, 0, 0,
3542 				      GFP_ATOMIC);
3543 	}
3544 
3545 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3546 		addrconf_dad_start(ifp);
3547 
3548 	return 0;
3549 }
3550 
3551 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3552 {
3553 	struct inet6_ifaddr *ifp, *tmp;
3554 	struct inet6_dev *idev;
3555 
3556 	idev = __in6_dev_get(dev);
3557 	if (!idev)
3558 		return;
3559 
3560 	write_lock_bh(&idev->lock);
3561 
3562 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3563 		if ((ifp->flags & IFA_F_PERMANENT) &&
3564 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3565 			write_unlock_bh(&idev->lock);
3566 			in6_ifa_hold(ifp);
3567 			ipv6_del_addr(ifp);
3568 			write_lock_bh(&idev->lock);
3569 
3570 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3571 					     idev->dev->name, &ifp->addr);
3572 		}
3573 	}
3574 
3575 	write_unlock_bh(&idev->lock);
3576 }
3577 
3578 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3579 			   void *ptr)
3580 {
3581 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3582 	struct netdev_notifier_change_info *change_info;
3583 	struct netdev_notifier_changeupper_info *info;
3584 	struct inet6_dev *idev = __in6_dev_get(dev);
3585 	struct net *net = dev_net(dev);
3586 	int run_pending = 0;
3587 	int err;
3588 
3589 	switch (event) {
3590 	case NETDEV_REGISTER:
3591 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3592 			idev = ipv6_add_dev(dev);
3593 			if (IS_ERR(idev))
3594 				return notifier_from_errno(PTR_ERR(idev));
3595 		}
3596 		break;
3597 
3598 	case NETDEV_CHANGEMTU:
3599 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3600 		if (dev->mtu < IPV6_MIN_MTU) {
3601 			addrconf_ifdown(dev, dev != net->loopback_dev);
3602 			break;
3603 		}
3604 
3605 		if (idev) {
3606 			rt6_mtu_change(dev, dev->mtu);
3607 			idev->cnf.mtu6 = dev->mtu;
3608 			break;
3609 		}
3610 
3611 		/* allocate new idev */
3612 		idev = ipv6_add_dev(dev);
3613 		if (IS_ERR(idev))
3614 			break;
3615 
3616 		/* device is still not ready */
3617 		if (!(idev->if_flags & IF_READY))
3618 			break;
3619 
3620 		run_pending = 1;
3621 		fallthrough;
3622 	case NETDEV_UP:
3623 	case NETDEV_CHANGE:
3624 		if (idev && idev->cnf.disable_ipv6)
3625 			break;
3626 
3627 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3628 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3629 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3630 				ipv6_mc_up(idev);
3631 			break;
3632 		}
3633 
3634 		if (event == NETDEV_UP) {
3635 			/* restore routes for permanent addresses */
3636 			addrconf_permanent_addr(net, dev);
3637 
3638 			if (!addrconf_link_ready(dev)) {
3639 				/* device is not ready yet. */
3640 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3641 					 dev->name);
3642 				break;
3643 			}
3644 
3645 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3646 				idev = ipv6_add_dev(dev);
3647 
3648 			if (!IS_ERR_OR_NULL(idev)) {
3649 				idev->if_flags |= IF_READY;
3650 				run_pending = 1;
3651 			}
3652 		} else if (event == NETDEV_CHANGE) {
3653 			if (!addrconf_link_ready(dev)) {
3654 				/* device is still not ready. */
3655 				rt6_sync_down_dev(dev, event);
3656 				break;
3657 			}
3658 
3659 			if (!IS_ERR_OR_NULL(idev)) {
3660 				if (idev->if_flags & IF_READY) {
3661 					/* device is already configured -
3662 					 * but resend MLD reports, we might
3663 					 * have roamed and need to update
3664 					 * multicast snooping switches
3665 					 */
3666 					ipv6_mc_up(idev);
3667 					change_info = ptr;
3668 					if (change_info->flags_changed & IFF_NOARP)
3669 						addrconf_dad_run(idev, true);
3670 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3671 					break;
3672 				}
3673 				idev->if_flags |= IF_READY;
3674 			}
3675 
3676 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3677 				 dev->name);
3678 
3679 			run_pending = 1;
3680 		}
3681 
3682 		addrconf_init_auto_addrs(dev);
3683 
3684 		if (!IS_ERR_OR_NULL(idev)) {
3685 			if (run_pending)
3686 				addrconf_dad_run(idev, false);
3687 
3688 			/* Device has an address by now */
3689 			rt6_sync_up(dev, RTNH_F_DEAD);
3690 
3691 			/*
3692 			 * If the MTU changed during the interface down,
3693 			 * when the interface up, the changed MTU must be
3694 			 * reflected in the idev as well as routers.
3695 			 */
3696 			if (idev->cnf.mtu6 != dev->mtu &&
3697 			    dev->mtu >= IPV6_MIN_MTU) {
3698 				rt6_mtu_change(dev, dev->mtu);
3699 				idev->cnf.mtu6 = dev->mtu;
3700 			}
3701 			idev->tstamp = jiffies;
3702 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3703 
3704 			/*
3705 			 * If the changed mtu during down is lower than
3706 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3707 			 */
3708 			if (dev->mtu < IPV6_MIN_MTU)
3709 				addrconf_ifdown(dev, dev != net->loopback_dev);
3710 		}
3711 		break;
3712 
3713 	case NETDEV_DOWN:
3714 	case NETDEV_UNREGISTER:
3715 		/*
3716 		 *	Remove all addresses from this interface.
3717 		 */
3718 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3719 		break;
3720 
3721 	case NETDEV_CHANGENAME:
3722 		if (idev) {
3723 			snmp6_unregister_dev(idev);
3724 			addrconf_sysctl_unregister(idev);
3725 			err = addrconf_sysctl_register(idev);
3726 			if (err)
3727 				return notifier_from_errno(err);
3728 			err = snmp6_register_dev(idev);
3729 			if (err) {
3730 				addrconf_sysctl_unregister(idev);
3731 				return notifier_from_errno(err);
3732 			}
3733 		}
3734 		break;
3735 
3736 	case NETDEV_PRE_TYPE_CHANGE:
3737 	case NETDEV_POST_TYPE_CHANGE:
3738 		if (idev)
3739 			addrconf_type_change(dev, event);
3740 		break;
3741 
3742 	case NETDEV_CHANGEUPPER:
3743 		info = ptr;
3744 
3745 		/* flush all routes if dev is linked to or unlinked from
3746 		 * an L3 master device (e.g., VRF)
3747 		 */
3748 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3749 			addrconf_ifdown(dev, false);
3750 	}
3751 
3752 	return NOTIFY_OK;
3753 }
3754 
3755 /*
3756  *	addrconf module should be notified of a device going up
3757  */
3758 static struct notifier_block ipv6_dev_notf = {
3759 	.notifier_call = addrconf_notify,
3760 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3761 };
3762 
3763 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3764 {
3765 	struct inet6_dev *idev;
3766 	ASSERT_RTNL();
3767 
3768 	idev = __in6_dev_get(dev);
3769 
3770 	if (event == NETDEV_POST_TYPE_CHANGE)
3771 		ipv6_mc_remap(idev);
3772 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3773 		ipv6_mc_unmap(idev);
3774 }
3775 
3776 static bool addr_is_local(const struct in6_addr *addr)
3777 {
3778 	return ipv6_addr_type(addr) &
3779 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3780 }
3781 
3782 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3783 {
3784 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3785 	struct net *net = dev_net(dev);
3786 	struct inet6_dev *idev;
3787 	struct inet6_ifaddr *ifa;
3788 	LIST_HEAD(tmp_addr_list);
3789 	bool keep_addr = false;
3790 	bool was_ready;
3791 	int state, i;
3792 
3793 	ASSERT_RTNL();
3794 
3795 	rt6_disable_ip(dev, event);
3796 
3797 	idev = __in6_dev_get(dev);
3798 	if (!idev)
3799 		return -ENODEV;
3800 
3801 	/*
3802 	 * Step 1: remove reference to ipv6 device from parent device.
3803 	 *	   Do not dev_put!
3804 	 */
3805 	if (unregister) {
3806 		idev->dead = 1;
3807 
3808 		/* protected by rtnl_lock */
3809 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3810 
3811 		/* Step 1.5: remove snmp6 entry */
3812 		snmp6_unregister_dev(idev);
3813 
3814 	}
3815 
3816 	/* combine the user config with event to determine if permanent
3817 	 * addresses are to be removed from address hash table
3818 	 */
3819 	if (!unregister && !idev->cnf.disable_ipv6) {
3820 		/* aggregate the system setting and interface setting */
3821 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3822 
3823 		if (!_keep_addr)
3824 			_keep_addr = idev->cnf.keep_addr_on_down;
3825 
3826 		keep_addr = (_keep_addr > 0);
3827 	}
3828 
3829 	/* Step 2: clear hash table */
3830 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3831 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3832 
3833 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3834 restart:
3835 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3836 			if (ifa->idev == idev) {
3837 				addrconf_del_dad_work(ifa);
3838 				/* combined flag + permanent flag decide if
3839 				 * address is retained on a down event
3840 				 */
3841 				if (!keep_addr ||
3842 				    !(ifa->flags & IFA_F_PERMANENT) ||
3843 				    addr_is_local(&ifa->addr)) {
3844 					hlist_del_init_rcu(&ifa->addr_lst);
3845 					goto restart;
3846 				}
3847 			}
3848 		}
3849 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3850 	}
3851 
3852 	write_lock_bh(&idev->lock);
3853 
3854 	addrconf_del_rs_timer(idev);
3855 
3856 	/* Step 2: clear flags for stateless addrconf, repeated down
3857 	 *         detection
3858 	 */
3859 	was_ready = idev->if_flags & IF_READY;
3860 	if (!unregister)
3861 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3862 
3863 	/* Step 3: clear tempaddr list */
3864 	while (!list_empty(&idev->tempaddr_list)) {
3865 		ifa = list_first_entry(&idev->tempaddr_list,
3866 				       struct inet6_ifaddr, tmp_list);
3867 		list_del(&ifa->tmp_list);
3868 		write_unlock_bh(&idev->lock);
3869 		spin_lock_bh(&ifa->lock);
3870 
3871 		if (ifa->ifpub) {
3872 			in6_ifa_put(ifa->ifpub);
3873 			ifa->ifpub = NULL;
3874 		}
3875 		spin_unlock_bh(&ifa->lock);
3876 		in6_ifa_put(ifa);
3877 		write_lock_bh(&idev->lock);
3878 	}
3879 
3880 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3881 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3882 	write_unlock_bh(&idev->lock);
3883 
3884 	while (!list_empty(&tmp_addr_list)) {
3885 		struct fib6_info *rt = NULL;
3886 		bool keep;
3887 
3888 		ifa = list_first_entry(&tmp_addr_list,
3889 				       struct inet6_ifaddr, if_list_aux);
3890 		list_del(&ifa->if_list_aux);
3891 
3892 		addrconf_del_dad_work(ifa);
3893 
3894 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3895 			!addr_is_local(&ifa->addr);
3896 
3897 		spin_lock_bh(&ifa->lock);
3898 
3899 		if (keep) {
3900 			/* set state to skip the notifier below */
3901 			state = INET6_IFADDR_STATE_DEAD;
3902 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3903 			if (!(ifa->flags & IFA_F_NODAD))
3904 				ifa->flags |= IFA_F_TENTATIVE;
3905 
3906 			rt = ifa->rt;
3907 			ifa->rt = NULL;
3908 		} else {
3909 			state = ifa->state;
3910 			ifa->state = INET6_IFADDR_STATE_DEAD;
3911 		}
3912 
3913 		spin_unlock_bh(&ifa->lock);
3914 
3915 		if (rt)
3916 			ip6_del_rt(net, rt, false);
3917 
3918 		if (state != INET6_IFADDR_STATE_DEAD) {
3919 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3920 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3921 		} else {
3922 			if (idev->cnf.forwarding)
3923 				addrconf_leave_anycast(ifa);
3924 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3925 		}
3926 
3927 		if (!keep) {
3928 			write_lock_bh(&idev->lock);
3929 			list_del_rcu(&ifa->if_list);
3930 			write_unlock_bh(&idev->lock);
3931 			in6_ifa_put(ifa);
3932 		}
3933 	}
3934 
3935 	/* Step 5: Discard anycast and multicast list */
3936 	if (unregister) {
3937 		ipv6_ac_destroy_dev(idev);
3938 		ipv6_mc_destroy_dev(idev);
3939 	} else if (was_ready) {
3940 		ipv6_mc_down(idev);
3941 	}
3942 
3943 	idev->tstamp = jiffies;
3944 	idev->ra_mtu = 0;
3945 
3946 	/* Last: Shot the device (if unregistered) */
3947 	if (unregister) {
3948 		addrconf_sysctl_unregister(idev);
3949 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3950 		neigh_ifdown(&nd_tbl, dev);
3951 		in6_dev_put(idev);
3952 	}
3953 	return 0;
3954 }
3955 
3956 static void addrconf_rs_timer(struct timer_list *t)
3957 {
3958 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3959 	struct net_device *dev = idev->dev;
3960 	struct in6_addr lladdr;
3961 
3962 	write_lock(&idev->lock);
3963 	if (idev->dead || !(idev->if_flags & IF_READY))
3964 		goto out;
3965 
3966 	if (!ipv6_accept_ra(idev))
3967 		goto out;
3968 
3969 	/* Announcement received after solicitation was sent */
3970 	if (idev->if_flags & IF_RA_RCVD)
3971 		goto out;
3972 
3973 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3974 		write_unlock(&idev->lock);
3975 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3976 			ndisc_send_rs(dev, &lladdr,
3977 				      &in6addr_linklocal_allrouters);
3978 		else
3979 			goto put;
3980 
3981 		write_lock(&idev->lock);
3982 		idev->rs_interval = rfc3315_s14_backoff_update(
3983 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3984 		/* The wait after the last probe can be shorter */
3985 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3986 					     idev->cnf.rtr_solicits) ?
3987 				      idev->cnf.rtr_solicit_delay :
3988 				      idev->rs_interval);
3989 	} else {
3990 		/*
3991 		 * Note: we do not support deprecated "all on-link"
3992 		 * assumption any longer.
3993 		 */
3994 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3995 	}
3996 
3997 out:
3998 	write_unlock(&idev->lock);
3999 put:
4000 	in6_dev_put(idev);
4001 }
4002 
4003 /*
4004  *	Duplicate Address Detection
4005  */
4006 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4007 {
4008 	unsigned long rand_num;
4009 	struct inet6_dev *idev = ifp->idev;
4010 	u64 nonce;
4011 
4012 	if (ifp->flags & IFA_F_OPTIMISTIC)
4013 		rand_num = 0;
4014 	else
4015 		rand_num = get_random_u32_below(idev->cnf.rtr_solicit_delay ? : 1);
4016 
4017 	nonce = 0;
4018 	if (idev->cnf.enhanced_dad ||
4019 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
4020 		do
4021 			get_random_bytes(&nonce, 6);
4022 		while (nonce == 0);
4023 	}
4024 	ifp->dad_nonce = nonce;
4025 	ifp->dad_probes = idev->cnf.dad_transmits;
4026 	addrconf_mod_dad_work(ifp, rand_num);
4027 }
4028 
4029 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4030 {
4031 	struct inet6_dev *idev = ifp->idev;
4032 	struct net_device *dev = idev->dev;
4033 	bool bump_id, notify = false;
4034 	struct net *net;
4035 
4036 	addrconf_join_solict(dev, &ifp->addr);
4037 
4038 	read_lock_bh(&idev->lock);
4039 	spin_lock(&ifp->lock);
4040 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4041 		goto out;
4042 
4043 	net = dev_net(dev);
4044 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4045 	    (net->ipv6.devconf_all->accept_dad < 1 &&
4046 	     idev->cnf.accept_dad < 1) ||
4047 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4048 	    ifp->flags & IFA_F_NODAD) {
4049 		bool send_na = false;
4050 
4051 		if (ifp->flags & IFA_F_TENTATIVE &&
4052 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4053 			send_na = true;
4054 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4055 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4056 		spin_unlock(&ifp->lock);
4057 		read_unlock_bh(&idev->lock);
4058 
4059 		addrconf_dad_completed(ifp, bump_id, send_na);
4060 		return;
4061 	}
4062 
4063 	if (!(idev->if_flags & IF_READY)) {
4064 		spin_unlock(&ifp->lock);
4065 		read_unlock_bh(&idev->lock);
4066 		/*
4067 		 * If the device is not ready:
4068 		 * - keep it tentative if it is a permanent address.
4069 		 * - otherwise, kill it.
4070 		 */
4071 		in6_ifa_hold(ifp);
4072 		addrconf_dad_stop(ifp, 0);
4073 		return;
4074 	}
4075 
4076 	/*
4077 	 * Optimistic nodes can start receiving
4078 	 * Frames right away
4079 	 */
4080 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4081 		ip6_ins_rt(net, ifp->rt);
4082 		if (ipv6_use_optimistic_addr(net, idev)) {
4083 			/* Because optimistic nodes can use this address,
4084 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4085 			 */
4086 			notify = true;
4087 		}
4088 	}
4089 
4090 	addrconf_dad_kick(ifp);
4091 out:
4092 	spin_unlock(&ifp->lock);
4093 	read_unlock_bh(&idev->lock);
4094 	if (notify)
4095 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4096 }
4097 
4098 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4099 {
4100 	bool begin_dad = false;
4101 
4102 	spin_lock_bh(&ifp->lock);
4103 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4104 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4105 		begin_dad = true;
4106 	}
4107 	spin_unlock_bh(&ifp->lock);
4108 
4109 	if (begin_dad)
4110 		addrconf_mod_dad_work(ifp, 0);
4111 }
4112 
4113 static void addrconf_dad_work(struct work_struct *w)
4114 {
4115 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4116 						struct inet6_ifaddr,
4117 						dad_work);
4118 	struct inet6_dev *idev = ifp->idev;
4119 	bool bump_id, disable_ipv6 = false;
4120 	struct in6_addr mcaddr;
4121 
4122 	enum {
4123 		DAD_PROCESS,
4124 		DAD_BEGIN,
4125 		DAD_ABORT,
4126 	} action = DAD_PROCESS;
4127 
4128 	rtnl_lock();
4129 
4130 	spin_lock_bh(&ifp->lock);
4131 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4132 		action = DAD_BEGIN;
4133 		ifp->state = INET6_IFADDR_STATE_DAD;
4134 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4135 		action = DAD_ABORT;
4136 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4137 
4138 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4139 		     idev->cnf.accept_dad > 1) &&
4140 		    !idev->cnf.disable_ipv6 &&
4141 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4142 			struct in6_addr addr;
4143 
4144 			addr.s6_addr32[0] = htonl(0xfe800000);
4145 			addr.s6_addr32[1] = 0;
4146 
4147 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4148 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4149 				/* DAD failed for link-local based on MAC */
4150 				idev->cnf.disable_ipv6 = 1;
4151 
4152 				pr_info("%s: IPv6 being disabled!\n",
4153 					ifp->idev->dev->name);
4154 				disable_ipv6 = true;
4155 			}
4156 		}
4157 	}
4158 	spin_unlock_bh(&ifp->lock);
4159 
4160 	if (action == DAD_BEGIN) {
4161 		addrconf_dad_begin(ifp);
4162 		goto out;
4163 	} else if (action == DAD_ABORT) {
4164 		in6_ifa_hold(ifp);
4165 		addrconf_dad_stop(ifp, 1);
4166 		if (disable_ipv6)
4167 			addrconf_ifdown(idev->dev, false);
4168 		goto out;
4169 	}
4170 
4171 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4172 		goto out;
4173 
4174 	write_lock_bh(&idev->lock);
4175 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4176 		write_unlock_bh(&idev->lock);
4177 		goto out;
4178 	}
4179 
4180 	spin_lock(&ifp->lock);
4181 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4182 		spin_unlock(&ifp->lock);
4183 		write_unlock_bh(&idev->lock);
4184 		goto out;
4185 	}
4186 
4187 	if (ifp->dad_probes == 0) {
4188 		bool send_na = false;
4189 
4190 		/*
4191 		 * DAD was successful
4192 		 */
4193 
4194 		if (ifp->flags & IFA_F_TENTATIVE &&
4195 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4196 			send_na = true;
4197 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4198 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4199 		spin_unlock(&ifp->lock);
4200 		write_unlock_bh(&idev->lock);
4201 
4202 		addrconf_dad_completed(ifp, bump_id, send_na);
4203 
4204 		goto out;
4205 	}
4206 
4207 	ifp->dad_probes--;
4208 	addrconf_mod_dad_work(ifp,
4209 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4210 				  HZ/100));
4211 	spin_unlock(&ifp->lock);
4212 	write_unlock_bh(&idev->lock);
4213 
4214 	/* send a neighbour solicitation for our addr */
4215 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4216 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4217 		      ifp->dad_nonce);
4218 out:
4219 	in6_ifa_put(ifp);
4220 	rtnl_unlock();
4221 }
4222 
4223 /* ifp->idev must be at least read locked */
4224 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4225 {
4226 	struct inet6_ifaddr *ifpiter;
4227 	struct inet6_dev *idev = ifp->idev;
4228 
4229 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4230 		if (ifpiter->scope > IFA_LINK)
4231 			break;
4232 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4233 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4234 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4235 		    IFA_F_PERMANENT)
4236 			return false;
4237 	}
4238 	return true;
4239 }
4240 
4241 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4242 				   bool send_na)
4243 {
4244 	struct net_device *dev = ifp->idev->dev;
4245 	struct in6_addr lladdr;
4246 	bool send_rs, send_mld;
4247 
4248 	addrconf_del_dad_work(ifp);
4249 
4250 	/*
4251 	 *	Configure the address for reception. Now it is valid.
4252 	 */
4253 
4254 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4255 
4256 	/* If added prefix is link local and we are prepared to process
4257 	   router advertisements, start sending router solicitations.
4258 	 */
4259 
4260 	read_lock_bh(&ifp->idev->lock);
4261 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4262 	send_rs = send_mld &&
4263 		  ipv6_accept_ra(ifp->idev) &&
4264 		  ifp->idev->cnf.rtr_solicits != 0 &&
4265 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4266 		  (dev->type != ARPHRD_TUNNEL) &&
4267 		  !netif_is_team_port(dev);
4268 	read_unlock_bh(&ifp->idev->lock);
4269 
4270 	/* While dad is in progress mld report's source address is in6_addrany.
4271 	 * Resend with proper ll now.
4272 	 */
4273 	if (send_mld)
4274 		ipv6_mc_dad_complete(ifp->idev);
4275 
4276 	/* send unsolicited NA if enabled */
4277 	if (send_na &&
4278 	    (ifp->idev->cnf.ndisc_notify ||
4279 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4280 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4281 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4282 			      /*solicited=*/ false, /*override=*/ true,
4283 			      /*inc_opt=*/ true);
4284 	}
4285 
4286 	if (send_rs) {
4287 		/*
4288 		 *	If a host as already performed a random delay
4289 		 *	[...] as part of DAD [...] there is no need
4290 		 *	to delay again before sending the first RS
4291 		 */
4292 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4293 			return;
4294 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4295 
4296 		write_lock_bh(&ifp->idev->lock);
4297 		spin_lock(&ifp->lock);
4298 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4299 			ifp->idev->cnf.rtr_solicit_interval);
4300 		ifp->idev->rs_probes = 1;
4301 		ifp->idev->if_flags |= IF_RS_SENT;
4302 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4303 		spin_unlock(&ifp->lock);
4304 		write_unlock_bh(&ifp->idev->lock);
4305 	}
4306 
4307 	if (bump_id)
4308 		rt_genid_bump_ipv6(dev_net(dev));
4309 
4310 	/* Make sure that a new temporary address will be created
4311 	 * before this temporary address becomes deprecated.
4312 	 */
4313 	if (ifp->flags & IFA_F_TEMPORARY)
4314 		addrconf_verify_rtnl(dev_net(dev));
4315 }
4316 
4317 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4318 {
4319 	struct inet6_ifaddr *ifp;
4320 
4321 	read_lock_bh(&idev->lock);
4322 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4323 		spin_lock(&ifp->lock);
4324 		if ((ifp->flags & IFA_F_TENTATIVE &&
4325 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4326 			if (restart)
4327 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4328 			addrconf_dad_kick(ifp);
4329 		}
4330 		spin_unlock(&ifp->lock);
4331 	}
4332 	read_unlock_bh(&idev->lock);
4333 }
4334 
4335 #ifdef CONFIG_PROC_FS
4336 struct if6_iter_state {
4337 	struct seq_net_private p;
4338 	int bucket;
4339 	int offset;
4340 };
4341 
4342 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4343 {
4344 	struct if6_iter_state *state = seq->private;
4345 	struct net *net = seq_file_net(seq);
4346 	struct inet6_ifaddr *ifa = NULL;
4347 	int p = 0;
4348 
4349 	/* initial bucket if pos is 0 */
4350 	if (pos == 0) {
4351 		state->bucket = 0;
4352 		state->offset = 0;
4353 	}
4354 
4355 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4356 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4357 					 addr_lst) {
4358 			/* sync with offset */
4359 			if (p < state->offset) {
4360 				p++;
4361 				continue;
4362 			}
4363 			return ifa;
4364 		}
4365 
4366 		/* prepare for next bucket */
4367 		state->offset = 0;
4368 		p = 0;
4369 	}
4370 	return NULL;
4371 }
4372 
4373 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4374 					 struct inet6_ifaddr *ifa)
4375 {
4376 	struct if6_iter_state *state = seq->private;
4377 	struct net *net = seq_file_net(seq);
4378 
4379 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4380 		state->offset++;
4381 		return ifa;
4382 	}
4383 
4384 	state->offset = 0;
4385 	while (++state->bucket < IN6_ADDR_HSIZE) {
4386 		hlist_for_each_entry_rcu(ifa,
4387 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4388 			return ifa;
4389 		}
4390 	}
4391 
4392 	return NULL;
4393 }
4394 
4395 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4396 	__acquires(rcu)
4397 {
4398 	rcu_read_lock();
4399 	return if6_get_first(seq, *pos);
4400 }
4401 
4402 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4403 {
4404 	struct inet6_ifaddr *ifa;
4405 
4406 	ifa = if6_get_next(seq, v);
4407 	++*pos;
4408 	return ifa;
4409 }
4410 
4411 static void if6_seq_stop(struct seq_file *seq, void *v)
4412 	__releases(rcu)
4413 {
4414 	rcu_read_unlock();
4415 }
4416 
4417 static int if6_seq_show(struct seq_file *seq, void *v)
4418 {
4419 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4420 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4421 		   &ifp->addr,
4422 		   ifp->idev->dev->ifindex,
4423 		   ifp->prefix_len,
4424 		   ifp->scope,
4425 		   (u8) ifp->flags,
4426 		   ifp->idev->dev->name);
4427 	return 0;
4428 }
4429 
4430 static const struct seq_operations if6_seq_ops = {
4431 	.start	= if6_seq_start,
4432 	.next	= if6_seq_next,
4433 	.show	= if6_seq_show,
4434 	.stop	= if6_seq_stop,
4435 };
4436 
4437 static int __net_init if6_proc_net_init(struct net *net)
4438 {
4439 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4440 			sizeof(struct if6_iter_state)))
4441 		return -ENOMEM;
4442 	return 0;
4443 }
4444 
4445 static void __net_exit if6_proc_net_exit(struct net *net)
4446 {
4447 	remove_proc_entry("if_inet6", net->proc_net);
4448 }
4449 
4450 static struct pernet_operations if6_proc_net_ops = {
4451 	.init = if6_proc_net_init,
4452 	.exit = if6_proc_net_exit,
4453 };
4454 
4455 int __init if6_proc_init(void)
4456 {
4457 	return register_pernet_subsys(&if6_proc_net_ops);
4458 }
4459 
4460 void if6_proc_exit(void)
4461 {
4462 	unregister_pernet_subsys(&if6_proc_net_ops);
4463 }
4464 #endif	/* CONFIG_PROC_FS */
4465 
4466 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4467 /* Check if address is a home address configured on any interface. */
4468 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4469 {
4470 	unsigned int hash = inet6_addr_hash(net, addr);
4471 	struct inet6_ifaddr *ifp = NULL;
4472 	int ret = 0;
4473 
4474 	rcu_read_lock();
4475 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4476 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4477 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4478 			ret = 1;
4479 			break;
4480 		}
4481 	}
4482 	rcu_read_unlock();
4483 	return ret;
4484 }
4485 #endif
4486 
4487 /* RFC6554 has some algorithm to avoid loops in segment routing by
4488  * checking if the segments contains any of a local interface address.
4489  *
4490  * Quote:
4491  *
4492  * To detect loops in the SRH, a router MUST determine if the SRH
4493  * includes multiple addresses assigned to any interface on that router.
4494  * If such addresses appear more than once and are separated by at least
4495  * one address not assigned to that router.
4496  */
4497 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4498 			  unsigned char nsegs)
4499 {
4500 	const struct in6_addr *addr;
4501 	int i, ret = 0, found = 0;
4502 	struct inet6_ifaddr *ifp;
4503 	bool separated = false;
4504 	unsigned int hash;
4505 	bool hash_found;
4506 
4507 	rcu_read_lock();
4508 	for (i = 0; i < nsegs; i++) {
4509 		addr = &segs[i];
4510 		hash = inet6_addr_hash(net, addr);
4511 
4512 		hash_found = false;
4513 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4514 
4515 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4516 				hash_found = true;
4517 				break;
4518 			}
4519 		}
4520 
4521 		if (hash_found) {
4522 			if (found > 1 && separated) {
4523 				ret = 1;
4524 				break;
4525 			}
4526 
4527 			separated = false;
4528 			found++;
4529 		} else {
4530 			separated = true;
4531 		}
4532 	}
4533 	rcu_read_unlock();
4534 
4535 	return ret;
4536 }
4537 
4538 /*
4539  *	Periodic address status verification
4540  */
4541 
4542 static void addrconf_verify_rtnl(struct net *net)
4543 {
4544 	unsigned long now, next, next_sec, next_sched;
4545 	struct inet6_ifaddr *ifp;
4546 	int i;
4547 
4548 	ASSERT_RTNL();
4549 
4550 	rcu_read_lock_bh();
4551 	now = jiffies;
4552 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4553 
4554 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4555 
4556 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4557 restart:
4558 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4559 			unsigned long age;
4560 
4561 			/* When setting preferred_lft to a value not zero or
4562 			 * infinity, while valid_lft is infinity
4563 			 * IFA_F_PERMANENT has a non-infinity life time.
4564 			 */
4565 			if ((ifp->flags & IFA_F_PERMANENT) &&
4566 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4567 				continue;
4568 
4569 			spin_lock(&ifp->lock);
4570 			/* We try to batch several events at once. */
4571 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4572 
4573 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4574 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4575 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4576 			    !ifp->regen_count && ifp->ifpub) {
4577 				/* This is a non-regenerated temporary addr. */
4578 
4579 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4580 					ifp->idev->cnf.dad_transmits *
4581 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4582 
4583 				if (age + regen_advance >= ifp->prefered_lft) {
4584 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4585 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4586 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4587 
4588 					ifp->regen_count++;
4589 					in6_ifa_hold(ifp);
4590 					in6_ifa_hold(ifpub);
4591 					spin_unlock(&ifp->lock);
4592 
4593 					spin_lock(&ifpub->lock);
4594 					ifpub->regen_count = 0;
4595 					spin_unlock(&ifpub->lock);
4596 					rcu_read_unlock_bh();
4597 					ipv6_create_tempaddr(ifpub, true);
4598 					in6_ifa_put(ifpub);
4599 					in6_ifa_put(ifp);
4600 					rcu_read_lock_bh();
4601 					goto restart;
4602 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4603 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4604 			}
4605 
4606 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4607 			    age >= ifp->valid_lft) {
4608 				spin_unlock(&ifp->lock);
4609 				in6_ifa_hold(ifp);
4610 				rcu_read_unlock_bh();
4611 				ipv6_del_addr(ifp);
4612 				rcu_read_lock_bh();
4613 				goto restart;
4614 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4615 				spin_unlock(&ifp->lock);
4616 				continue;
4617 			} else if (age >= ifp->prefered_lft) {
4618 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4619 				int deprecate = 0;
4620 
4621 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4622 					deprecate = 1;
4623 					ifp->flags |= IFA_F_DEPRECATED;
4624 				}
4625 
4626 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4627 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4628 					next = ifp->tstamp + ifp->valid_lft * HZ;
4629 
4630 				spin_unlock(&ifp->lock);
4631 
4632 				if (deprecate) {
4633 					in6_ifa_hold(ifp);
4634 
4635 					ipv6_ifa_notify(0, ifp);
4636 					in6_ifa_put(ifp);
4637 					goto restart;
4638 				}
4639 			} else {
4640 				/* ifp->prefered_lft <= ifp->valid_lft */
4641 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4642 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4643 				spin_unlock(&ifp->lock);
4644 			}
4645 		}
4646 	}
4647 
4648 	next_sec = round_jiffies_up(next);
4649 	next_sched = next;
4650 
4651 	/* If rounded timeout is accurate enough, accept it. */
4652 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4653 		next_sched = next_sec;
4654 
4655 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4656 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4657 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4658 
4659 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4660 		 now, next, next_sec, next_sched);
4661 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4662 	rcu_read_unlock_bh();
4663 }
4664 
4665 static void addrconf_verify_work(struct work_struct *w)
4666 {
4667 	struct net *net = container_of(to_delayed_work(w), struct net,
4668 				       ipv6.addr_chk_work);
4669 
4670 	rtnl_lock();
4671 	addrconf_verify_rtnl(net);
4672 	rtnl_unlock();
4673 }
4674 
4675 static void addrconf_verify(struct net *net)
4676 {
4677 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4678 }
4679 
4680 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4681 				     struct in6_addr **peer_pfx)
4682 {
4683 	struct in6_addr *pfx = NULL;
4684 
4685 	*peer_pfx = NULL;
4686 
4687 	if (addr)
4688 		pfx = nla_data(addr);
4689 
4690 	if (local) {
4691 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4692 			*peer_pfx = pfx;
4693 		pfx = nla_data(local);
4694 	}
4695 
4696 	return pfx;
4697 }
4698 
4699 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4700 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4701 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4702 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4703 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4704 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4705 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4706 	[IFA_PROTO]		= { .type = NLA_U8 },
4707 };
4708 
4709 static int
4710 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4711 		  struct netlink_ext_ack *extack)
4712 {
4713 	struct net *net = sock_net(skb->sk);
4714 	struct ifaddrmsg *ifm;
4715 	struct nlattr *tb[IFA_MAX+1];
4716 	struct in6_addr *pfx, *peer_pfx;
4717 	u32 ifa_flags;
4718 	int err;
4719 
4720 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4721 				     ifa_ipv6_policy, extack);
4722 	if (err < 0)
4723 		return err;
4724 
4725 	ifm = nlmsg_data(nlh);
4726 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4727 	if (!pfx)
4728 		return -EINVAL;
4729 
4730 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4731 
4732 	/* We ignore other flags so far. */
4733 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4734 
4735 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4736 			      ifm->ifa_prefixlen, extack);
4737 }
4738 
4739 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4740 			       unsigned long expires, u32 flags,
4741 			       bool modify_peer)
4742 {
4743 	struct fib6_info *f6i;
4744 	u32 prio;
4745 
4746 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4747 					ifp->prefix_len,
4748 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4749 	if (!f6i)
4750 		return -ENOENT;
4751 
4752 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4753 	if (f6i->fib6_metric != prio) {
4754 		/* delete old one */
4755 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4756 
4757 		/* add new one */
4758 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4759 				      ifp->prefix_len,
4760 				      ifp->rt_priority, ifp->idev->dev,
4761 				      expires, flags, GFP_KERNEL);
4762 	} else {
4763 		if (!expires)
4764 			fib6_clean_expires(f6i);
4765 		else
4766 			fib6_set_expires(f6i, expires);
4767 
4768 		fib6_info_release(f6i);
4769 	}
4770 
4771 	return 0;
4772 }
4773 
4774 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4775 			     struct ifa6_config *cfg)
4776 {
4777 	u32 flags;
4778 	clock_t expires;
4779 	unsigned long timeout;
4780 	bool was_managetempaddr;
4781 	bool had_prefixroute;
4782 	bool new_peer = false;
4783 
4784 	ASSERT_RTNL();
4785 
4786 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4787 		return -EINVAL;
4788 
4789 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4790 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4791 		return -EINVAL;
4792 
4793 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4794 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4795 
4796 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4797 	if (addrconf_finite_timeout(timeout)) {
4798 		expires = jiffies_to_clock_t(timeout * HZ);
4799 		cfg->valid_lft = timeout;
4800 		flags = RTF_EXPIRES;
4801 	} else {
4802 		expires = 0;
4803 		flags = 0;
4804 		cfg->ifa_flags |= IFA_F_PERMANENT;
4805 	}
4806 
4807 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4808 	if (addrconf_finite_timeout(timeout)) {
4809 		if (timeout == 0)
4810 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4811 		cfg->preferred_lft = timeout;
4812 	}
4813 
4814 	if (cfg->peer_pfx &&
4815 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4816 		if (!ipv6_addr_any(&ifp->peer_addr))
4817 			cleanup_prefix_route(ifp, expires, true, true);
4818 		new_peer = true;
4819 	}
4820 
4821 	spin_lock_bh(&ifp->lock);
4822 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4823 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4824 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4825 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4826 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4827 			IFA_F_NOPREFIXROUTE);
4828 	ifp->flags |= cfg->ifa_flags;
4829 	ifp->tstamp = jiffies;
4830 	ifp->valid_lft = cfg->valid_lft;
4831 	ifp->prefered_lft = cfg->preferred_lft;
4832 	ifp->ifa_proto = cfg->ifa_proto;
4833 
4834 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4835 		ifp->rt_priority = cfg->rt_priority;
4836 
4837 	if (new_peer)
4838 		ifp->peer_addr = *cfg->peer_pfx;
4839 
4840 	spin_unlock_bh(&ifp->lock);
4841 	if (!(ifp->flags&IFA_F_TENTATIVE))
4842 		ipv6_ifa_notify(0, ifp);
4843 
4844 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4845 		int rc = -ENOENT;
4846 
4847 		if (had_prefixroute)
4848 			rc = modify_prefix_route(ifp, expires, flags, false);
4849 
4850 		/* prefix route could have been deleted; if so restore it */
4851 		if (rc == -ENOENT) {
4852 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4853 					      ifp->rt_priority, ifp->idev->dev,
4854 					      expires, flags, GFP_KERNEL);
4855 		}
4856 
4857 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4858 			rc = modify_prefix_route(ifp, expires, flags, true);
4859 
4860 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4861 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4862 					      ifp->rt_priority, ifp->idev->dev,
4863 					      expires, flags, GFP_KERNEL);
4864 		}
4865 	} else if (had_prefixroute) {
4866 		enum cleanup_prefix_rt_t action;
4867 		unsigned long rt_expires;
4868 
4869 		write_lock_bh(&ifp->idev->lock);
4870 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4871 		write_unlock_bh(&ifp->idev->lock);
4872 
4873 		if (action != CLEANUP_PREFIX_RT_NOP) {
4874 			cleanup_prefix_route(ifp, rt_expires,
4875 				action == CLEANUP_PREFIX_RT_DEL, false);
4876 		}
4877 	}
4878 
4879 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4880 		if (was_managetempaddr &&
4881 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4882 			cfg->valid_lft = 0;
4883 			cfg->preferred_lft = 0;
4884 		}
4885 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4886 				 cfg->preferred_lft, !was_managetempaddr,
4887 				 jiffies);
4888 	}
4889 
4890 	addrconf_verify_rtnl(net);
4891 
4892 	return 0;
4893 }
4894 
4895 static int
4896 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4897 		  struct netlink_ext_ack *extack)
4898 {
4899 	struct net *net = sock_net(skb->sk);
4900 	struct ifaddrmsg *ifm;
4901 	struct nlattr *tb[IFA_MAX+1];
4902 	struct in6_addr *peer_pfx;
4903 	struct inet6_ifaddr *ifa;
4904 	struct net_device *dev;
4905 	struct inet6_dev *idev;
4906 	struct ifa6_config cfg;
4907 	int err;
4908 
4909 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4910 				     ifa_ipv6_policy, extack);
4911 	if (err < 0)
4912 		return err;
4913 
4914 	memset(&cfg, 0, sizeof(cfg));
4915 
4916 	ifm = nlmsg_data(nlh);
4917 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4918 	if (!cfg.pfx)
4919 		return -EINVAL;
4920 
4921 	cfg.peer_pfx = peer_pfx;
4922 	cfg.plen = ifm->ifa_prefixlen;
4923 	if (tb[IFA_RT_PRIORITY])
4924 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4925 
4926 	if (tb[IFA_PROTO])
4927 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4928 
4929 	cfg.valid_lft = INFINITY_LIFE_TIME;
4930 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4931 
4932 	if (tb[IFA_CACHEINFO]) {
4933 		struct ifa_cacheinfo *ci;
4934 
4935 		ci = nla_data(tb[IFA_CACHEINFO]);
4936 		cfg.valid_lft = ci->ifa_valid;
4937 		cfg.preferred_lft = ci->ifa_prefered;
4938 	}
4939 
4940 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4941 	if (!dev) {
4942 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
4943 		return -ENODEV;
4944 	}
4945 
4946 	if (tb[IFA_FLAGS])
4947 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4948 	else
4949 		cfg.ifa_flags = ifm->ifa_flags;
4950 
4951 	/* We ignore other flags so far. */
4952 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4953 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4954 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4955 
4956 	idev = ipv6_find_idev(dev);
4957 	if (IS_ERR(idev))
4958 		return PTR_ERR(idev);
4959 
4960 	if (!ipv6_allow_optimistic_dad(net, idev))
4961 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4962 
4963 	if (cfg.ifa_flags & IFA_F_NODAD &&
4964 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4965 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4966 		return -EINVAL;
4967 	}
4968 
4969 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4970 	if (!ifa) {
4971 		/*
4972 		 * It would be best to check for !NLM_F_CREATE here but
4973 		 * userspace already relies on not having to provide this.
4974 		 */
4975 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4976 	}
4977 
4978 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4979 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
4980 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
4981 		err = -EEXIST;
4982 	} else {
4983 		err = inet6_addr_modify(net, ifa, &cfg);
4984 	}
4985 
4986 	in6_ifa_put(ifa);
4987 
4988 	return err;
4989 }
4990 
4991 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4992 			  u8 scope, int ifindex)
4993 {
4994 	struct ifaddrmsg *ifm;
4995 
4996 	ifm = nlmsg_data(nlh);
4997 	ifm->ifa_family = AF_INET6;
4998 	ifm->ifa_prefixlen = prefixlen;
4999 	ifm->ifa_flags = flags;
5000 	ifm->ifa_scope = scope;
5001 	ifm->ifa_index = ifindex;
5002 }
5003 
5004 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5005 			 unsigned long tstamp, u32 preferred, u32 valid)
5006 {
5007 	struct ifa_cacheinfo ci;
5008 
5009 	ci.cstamp = cstamp_delta(cstamp);
5010 	ci.tstamp = cstamp_delta(tstamp);
5011 	ci.ifa_prefered = preferred;
5012 	ci.ifa_valid = valid;
5013 
5014 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5015 }
5016 
5017 static inline int rt_scope(int ifa_scope)
5018 {
5019 	if (ifa_scope & IFA_HOST)
5020 		return RT_SCOPE_HOST;
5021 	else if (ifa_scope & IFA_LINK)
5022 		return RT_SCOPE_LINK;
5023 	else if (ifa_scope & IFA_SITE)
5024 		return RT_SCOPE_SITE;
5025 	else
5026 		return RT_SCOPE_UNIVERSE;
5027 }
5028 
5029 static inline int inet6_ifaddr_msgsize(void)
5030 {
5031 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5032 	       + nla_total_size(16) /* IFA_LOCAL */
5033 	       + nla_total_size(16) /* IFA_ADDRESS */
5034 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5035 	       + nla_total_size(4)  /* IFA_FLAGS */
5036 	       + nla_total_size(1)  /* IFA_PROTO */
5037 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5038 }
5039 
5040 enum addr_type_t {
5041 	UNICAST_ADDR,
5042 	MULTICAST_ADDR,
5043 	ANYCAST_ADDR,
5044 };
5045 
5046 struct inet6_fill_args {
5047 	u32 portid;
5048 	u32 seq;
5049 	int event;
5050 	unsigned int flags;
5051 	int netnsid;
5052 	int ifindex;
5053 	enum addr_type_t type;
5054 };
5055 
5056 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
5057 			     struct inet6_fill_args *args)
5058 {
5059 	struct nlmsghdr  *nlh;
5060 	u32 preferred, valid;
5061 
5062 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5063 			sizeof(struct ifaddrmsg), args->flags);
5064 	if (!nlh)
5065 		return -EMSGSIZE;
5066 
5067 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5068 		      ifa->idev->dev->ifindex);
5069 
5070 	if (args->netnsid >= 0 &&
5071 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5072 		goto error;
5073 
5074 	spin_lock_bh(&ifa->lock);
5075 	if (!((ifa->flags&IFA_F_PERMANENT) &&
5076 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
5077 		preferred = ifa->prefered_lft;
5078 		valid = ifa->valid_lft;
5079 		if (preferred != INFINITY_LIFE_TIME) {
5080 			long tval = (jiffies - ifa->tstamp)/HZ;
5081 			if (preferred > tval)
5082 				preferred -= tval;
5083 			else
5084 				preferred = 0;
5085 			if (valid != INFINITY_LIFE_TIME) {
5086 				if (valid > tval)
5087 					valid -= tval;
5088 				else
5089 					valid = 0;
5090 			}
5091 		}
5092 	} else {
5093 		preferred = INFINITY_LIFE_TIME;
5094 		valid = INFINITY_LIFE_TIME;
5095 	}
5096 	spin_unlock_bh(&ifa->lock);
5097 
5098 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5099 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5100 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5101 			goto error;
5102 	} else
5103 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5104 			goto error;
5105 
5106 	if (ifa->rt_priority &&
5107 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
5108 		goto error;
5109 
5110 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5111 		goto error;
5112 
5113 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5114 		goto error;
5115 
5116 	if (ifa->ifa_proto &&
5117 	    nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto))
5118 		goto error;
5119 
5120 	nlmsg_end(skb, nlh);
5121 	return 0;
5122 
5123 error:
5124 	nlmsg_cancel(skb, nlh);
5125 	return -EMSGSIZE;
5126 }
5127 
5128 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5129 			       struct inet6_fill_args *args)
5130 {
5131 	struct nlmsghdr  *nlh;
5132 	u8 scope = RT_SCOPE_UNIVERSE;
5133 	int ifindex = ifmca->idev->dev->ifindex;
5134 
5135 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5136 		scope = RT_SCOPE_SITE;
5137 
5138 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5139 			sizeof(struct ifaddrmsg), args->flags);
5140 	if (!nlh)
5141 		return -EMSGSIZE;
5142 
5143 	if (args->netnsid >= 0 &&
5144 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5145 		nlmsg_cancel(skb, nlh);
5146 		return -EMSGSIZE;
5147 	}
5148 
5149 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5150 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5151 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5152 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5153 		nlmsg_cancel(skb, nlh);
5154 		return -EMSGSIZE;
5155 	}
5156 
5157 	nlmsg_end(skb, nlh);
5158 	return 0;
5159 }
5160 
5161 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5162 			       struct inet6_fill_args *args)
5163 {
5164 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5165 	int ifindex = dev ? dev->ifindex : 1;
5166 	struct nlmsghdr  *nlh;
5167 	u8 scope = RT_SCOPE_UNIVERSE;
5168 
5169 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5170 		scope = RT_SCOPE_SITE;
5171 
5172 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5173 			sizeof(struct ifaddrmsg), args->flags);
5174 	if (!nlh)
5175 		return -EMSGSIZE;
5176 
5177 	if (args->netnsid >= 0 &&
5178 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5179 		nlmsg_cancel(skb, nlh);
5180 		return -EMSGSIZE;
5181 	}
5182 
5183 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5184 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5185 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5186 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5187 		nlmsg_cancel(skb, nlh);
5188 		return -EMSGSIZE;
5189 	}
5190 
5191 	nlmsg_end(skb, nlh);
5192 	return 0;
5193 }
5194 
5195 /* called with rcu_read_lock() */
5196 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5197 			  struct netlink_callback *cb, int s_ip_idx,
5198 			  struct inet6_fill_args *fillargs)
5199 {
5200 	struct ifmcaddr6 *ifmca;
5201 	struct ifacaddr6 *ifaca;
5202 	int ip_idx = 0;
5203 	int err = 1;
5204 
5205 	read_lock_bh(&idev->lock);
5206 	switch (fillargs->type) {
5207 	case UNICAST_ADDR: {
5208 		struct inet6_ifaddr *ifa;
5209 		fillargs->event = RTM_NEWADDR;
5210 
5211 		/* unicast address incl. temp addr */
5212 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5213 			if (ip_idx < s_ip_idx)
5214 				goto next;
5215 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5216 			if (err < 0)
5217 				break;
5218 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5219 next:
5220 			ip_idx++;
5221 		}
5222 		break;
5223 	}
5224 	case MULTICAST_ADDR:
5225 		read_unlock_bh(&idev->lock);
5226 		fillargs->event = RTM_GETMULTICAST;
5227 
5228 		/* multicast address */
5229 		for (ifmca = rtnl_dereference(idev->mc_list);
5230 		     ifmca;
5231 		     ifmca = rtnl_dereference(ifmca->next), ip_idx++) {
5232 			if (ip_idx < s_ip_idx)
5233 				continue;
5234 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5235 			if (err < 0)
5236 				break;
5237 		}
5238 		read_lock_bh(&idev->lock);
5239 		break;
5240 	case ANYCAST_ADDR:
5241 		fillargs->event = RTM_GETANYCAST;
5242 		/* anycast address */
5243 		for (ifaca = idev->ac_list; ifaca;
5244 		     ifaca = ifaca->aca_next, ip_idx++) {
5245 			if (ip_idx < s_ip_idx)
5246 				continue;
5247 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5248 			if (err < 0)
5249 				break;
5250 		}
5251 		break;
5252 	default:
5253 		break;
5254 	}
5255 	read_unlock_bh(&idev->lock);
5256 	cb->args[2] = ip_idx;
5257 	return err;
5258 }
5259 
5260 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5261 				       struct inet6_fill_args *fillargs,
5262 				       struct net **tgt_net, struct sock *sk,
5263 				       struct netlink_callback *cb)
5264 {
5265 	struct netlink_ext_ack *extack = cb->extack;
5266 	struct nlattr *tb[IFA_MAX+1];
5267 	struct ifaddrmsg *ifm;
5268 	int err, i;
5269 
5270 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5271 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5272 		return -EINVAL;
5273 	}
5274 
5275 	ifm = nlmsg_data(nlh);
5276 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5277 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5278 		return -EINVAL;
5279 	}
5280 
5281 	fillargs->ifindex = ifm->ifa_index;
5282 	if (fillargs->ifindex) {
5283 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5284 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5285 	}
5286 
5287 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5288 					    ifa_ipv6_policy, extack);
5289 	if (err < 0)
5290 		return err;
5291 
5292 	for (i = 0; i <= IFA_MAX; ++i) {
5293 		if (!tb[i])
5294 			continue;
5295 
5296 		if (i == IFA_TARGET_NETNSID) {
5297 			struct net *net;
5298 
5299 			fillargs->netnsid = nla_get_s32(tb[i]);
5300 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5301 			if (IS_ERR(net)) {
5302 				fillargs->netnsid = -1;
5303 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5304 				return PTR_ERR(net);
5305 			}
5306 			*tgt_net = net;
5307 		} else {
5308 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5309 			return -EINVAL;
5310 		}
5311 	}
5312 
5313 	return 0;
5314 }
5315 
5316 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5317 			   enum addr_type_t type)
5318 {
5319 	const struct nlmsghdr *nlh = cb->nlh;
5320 	struct inet6_fill_args fillargs = {
5321 		.portid = NETLINK_CB(cb->skb).portid,
5322 		.seq = cb->nlh->nlmsg_seq,
5323 		.flags = NLM_F_MULTI,
5324 		.netnsid = -1,
5325 		.type = type,
5326 	};
5327 	struct net *tgt_net = sock_net(skb->sk);
5328 	int idx, s_idx, s_ip_idx;
5329 	int h, s_h;
5330 	struct net_device *dev;
5331 	struct inet6_dev *idev;
5332 	struct hlist_head *head;
5333 	int err = 0;
5334 
5335 	s_h = cb->args[0];
5336 	s_idx = idx = cb->args[1];
5337 	s_ip_idx = cb->args[2];
5338 
5339 	if (cb->strict_check) {
5340 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5341 						  skb->sk, cb);
5342 		if (err < 0)
5343 			goto put_tgt_net;
5344 
5345 		err = 0;
5346 		if (fillargs.ifindex) {
5347 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5348 			if (!dev) {
5349 				err = -ENODEV;
5350 				goto put_tgt_net;
5351 			}
5352 			idev = __in6_dev_get(dev);
5353 			if (idev) {
5354 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5355 						     &fillargs);
5356 				if (err > 0)
5357 					err = 0;
5358 			}
5359 			goto put_tgt_net;
5360 		}
5361 	}
5362 
5363 	rcu_read_lock();
5364 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5365 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5366 		idx = 0;
5367 		head = &tgt_net->dev_index_head[h];
5368 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5369 			if (idx < s_idx)
5370 				goto cont;
5371 			if (h > s_h || idx > s_idx)
5372 				s_ip_idx = 0;
5373 			idev = __in6_dev_get(dev);
5374 			if (!idev)
5375 				goto cont;
5376 
5377 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5378 					   &fillargs) < 0)
5379 				goto done;
5380 cont:
5381 			idx++;
5382 		}
5383 	}
5384 done:
5385 	rcu_read_unlock();
5386 	cb->args[0] = h;
5387 	cb->args[1] = idx;
5388 put_tgt_net:
5389 	if (fillargs.netnsid >= 0)
5390 		put_net(tgt_net);
5391 
5392 	return skb->len ? : err;
5393 }
5394 
5395 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5396 {
5397 	enum addr_type_t type = UNICAST_ADDR;
5398 
5399 	return inet6_dump_addr(skb, cb, type);
5400 }
5401 
5402 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5403 {
5404 	enum addr_type_t type = MULTICAST_ADDR;
5405 
5406 	return inet6_dump_addr(skb, cb, type);
5407 }
5408 
5409 
5410 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5411 {
5412 	enum addr_type_t type = ANYCAST_ADDR;
5413 
5414 	return inet6_dump_addr(skb, cb, type);
5415 }
5416 
5417 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5418 				       const struct nlmsghdr *nlh,
5419 				       struct nlattr **tb,
5420 				       struct netlink_ext_ack *extack)
5421 {
5422 	struct ifaddrmsg *ifm;
5423 	int i, err;
5424 
5425 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5426 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5427 		return -EINVAL;
5428 	}
5429 
5430 	if (!netlink_strict_get_check(skb))
5431 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5432 					      ifa_ipv6_policy, extack);
5433 
5434 	ifm = nlmsg_data(nlh);
5435 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5436 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5437 		return -EINVAL;
5438 	}
5439 
5440 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5441 					    ifa_ipv6_policy, extack);
5442 	if (err)
5443 		return err;
5444 
5445 	for (i = 0; i <= IFA_MAX; i++) {
5446 		if (!tb[i])
5447 			continue;
5448 
5449 		switch (i) {
5450 		case IFA_TARGET_NETNSID:
5451 		case IFA_ADDRESS:
5452 		case IFA_LOCAL:
5453 			break;
5454 		default:
5455 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5456 			return -EINVAL;
5457 		}
5458 	}
5459 
5460 	return 0;
5461 }
5462 
5463 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5464 			     struct netlink_ext_ack *extack)
5465 {
5466 	struct net *tgt_net = sock_net(in_skb->sk);
5467 	struct inet6_fill_args fillargs = {
5468 		.portid = NETLINK_CB(in_skb).portid,
5469 		.seq = nlh->nlmsg_seq,
5470 		.event = RTM_NEWADDR,
5471 		.flags = 0,
5472 		.netnsid = -1,
5473 	};
5474 	struct ifaddrmsg *ifm;
5475 	struct nlattr *tb[IFA_MAX+1];
5476 	struct in6_addr *addr = NULL, *peer;
5477 	struct net_device *dev = NULL;
5478 	struct inet6_ifaddr *ifa;
5479 	struct sk_buff *skb;
5480 	int err;
5481 
5482 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5483 	if (err < 0)
5484 		return err;
5485 
5486 	if (tb[IFA_TARGET_NETNSID]) {
5487 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5488 
5489 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5490 						  fillargs.netnsid);
5491 		if (IS_ERR(tgt_net))
5492 			return PTR_ERR(tgt_net);
5493 	}
5494 
5495 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5496 	if (!addr)
5497 		return -EINVAL;
5498 
5499 	ifm = nlmsg_data(nlh);
5500 	if (ifm->ifa_index)
5501 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5502 
5503 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5504 	if (!ifa) {
5505 		err = -EADDRNOTAVAIL;
5506 		goto errout;
5507 	}
5508 
5509 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5510 	if (!skb) {
5511 		err = -ENOBUFS;
5512 		goto errout_ifa;
5513 	}
5514 
5515 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5516 	if (err < 0) {
5517 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5518 		WARN_ON(err == -EMSGSIZE);
5519 		kfree_skb(skb);
5520 		goto errout_ifa;
5521 	}
5522 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5523 errout_ifa:
5524 	in6_ifa_put(ifa);
5525 errout:
5526 	dev_put(dev);
5527 	if (fillargs.netnsid >= 0)
5528 		put_net(tgt_net);
5529 
5530 	return err;
5531 }
5532 
5533 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5534 {
5535 	struct sk_buff *skb;
5536 	struct net *net = dev_net(ifa->idev->dev);
5537 	struct inet6_fill_args fillargs = {
5538 		.portid = 0,
5539 		.seq = 0,
5540 		.event = event,
5541 		.flags = 0,
5542 		.netnsid = -1,
5543 	};
5544 	int err = -ENOBUFS;
5545 
5546 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5547 	if (!skb)
5548 		goto errout;
5549 
5550 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5551 	if (err < 0) {
5552 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5553 		WARN_ON(err == -EMSGSIZE);
5554 		kfree_skb(skb);
5555 		goto errout;
5556 	}
5557 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5558 	return;
5559 errout:
5560 	if (err < 0)
5561 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5562 }
5563 
5564 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5565 				__s32 *array, int bytes)
5566 {
5567 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5568 
5569 	memset(array, 0, bytes);
5570 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5571 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5572 	array[DEVCONF_MTU6] = cnf->mtu6;
5573 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5574 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5575 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5576 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5577 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5578 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5579 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5580 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5581 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5582 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5583 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5584 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5585 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5586 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5587 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5588 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5589 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5590 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5591 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5592 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5593 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5594 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5595 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5596 	array[DEVCONF_RA_DEFRTR_METRIC] = cnf->ra_defrtr_metric;
5597 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5598 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5599 #ifdef CONFIG_IPV6_ROUTER_PREF
5600 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5601 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5602 		jiffies_to_msecs(cnf->rtr_probe_interval);
5603 #ifdef CONFIG_IPV6_ROUTE_INFO
5604 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5605 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5606 #endif
5607 #endif
5608 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5609 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5610 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5611 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5612 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5613 #endif
5614 #ifdef CONFIG_IPV6_MROUTE
5615 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5616 #endif
5617 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5618 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5619 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5620 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5621 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5622 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5623 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5624 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5625 	/* we omit DEVCONF_STABLE_SECRET for now */
5626 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5627 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5628 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5629 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5630 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5631 #ifdef CONFIG_IPV6_SEG6_HMAC
5632 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5633 #endif
5634 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5635 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5636 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5637 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5638 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5639 	array[DEVCONF_IOAM6_ENABLED] = cnf->ioam6_enabled;
5640 	array[DEVCONF_IOAM6_ID] = cnf->ioam6_id;
5641 	array[DEVCONF_IOAM6_ID_WIDE] = cnf->ioam6_id_wide;
5642 	array[DEVCONF_NDISC_EVICT_NOCARRIER] = cnf->ndisc_evict_nocarrier;
5643 	array[DEVCONF_ACCEPT_UNTRACKED_NA] = cnf->accept_untracked_na;
5644 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = cnf->accept_ra_min_lft;
5645 }
5646 
5647 static inline size_t inet6_ifla6_size(void)
5648 {
5649 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5650 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5651 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5652 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5653 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5654 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5655 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5656 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5657 	     + 0;
5658 }
5659 
5660 static inline size_t inet6_if_nlmsg_size(void)
5661 {
5662 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5663 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5664 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5665 	       + nla_total_size(4) /* IFLA_MTU */
5666 	       + nla_total_size(4) /* IFLA_LINK */
5667 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5668 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5669 }
5670 
5671 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5672 					int bytes)
5673 {
5674 	int i;
5675 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5676 	BUG_ON(pad < 0);
5677 
5678 	/* Use put_unaligned() because stats may not be aligned for u64. */
5679 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5680 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5681 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5682 
5683 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5684 }
5685 
5686 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5687 					int bytes, size_t syncpoff)
5688 {
5689 	int i, c;
5690 	u64 buff[IPSTATS_MIB_MAX];
5691 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5692 
5693 	BUG_ON(pad < 0);
5694 
5695 	memset(buff, 0, sizeof(buff));
5696 	buff[0] = IPSTATS_MIB_MAX;
5697 
5698 	for_each_possible_cpu(c) {
5699 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5700 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5701 	}
5702 
5703 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5704 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5705 }
5706 
5707 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5708 			     int bytes)
5709 {
5710 	switch (attrtype) {
5711 	case IFLA_INET6_STATS:
5712 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5713 				     offsetof(struct ipstats_mib, syncp));
5714 		break;
5715 	case IFLA_INET6_ICMP6STATS:
5716 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5717 		break;
5718 	}
5719 }
5720 
5721 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5722 				  u32 ext_filter_mask)
5723 {
5724 	struct nlattr *nla;
5725 	struct ifla_cacheinfo ci;
5726 
5727 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5728 		goto nla_put_failure;
5729 	ci.max_reasm_len = IPV6_MAXPLEN;
5730 	ci.tstamp = cstamp_delta(idev->tstamp);
5731 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5732 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5733 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5734 		goto nla_put_failure;
5735 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5736 	if (!nla)
5737 		goto nla_put_failure;
5738 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5739 
5740 	/* XXX - MC not implemented */
5741 
5742 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5743 		return 0;
5744 
5745 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5746 	if (!nla)
5747 		goto nla_put_failure;
5748 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5749 
5750 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5751 	if (!nla)
5752 		goto nla_put_failure;
5753 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5754 
5755 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5756 	if (!nla)
5757 		goto nla_put_failure;
5758 	read_lock_bh(&idev->lock);
5759 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5760 	read_unlock_bh(&idev->lock);
5761 
5762 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5763 		goto nla_put_failure;
5764 
5765 	if (idev->ra_mtu &&
5766 	    nla_put_u32(skb, IFLA_INET6_RA_MTU, idev->ra_mtu))
5767 		goto nla_put_failure;
5768 
5769 	return 0;
5770 
5771 nla_put_failure:
5772 	return -EMSGSIZE;
5773 }
5774 
5775 static size_t inet6_get_link_af_size(const struct net_device *dev,
5776 				     u32 ext_filter_mask)
5777 {
5778 	if (!__in6_dev_get(dev))
5779 		return 0;
5780 
5781 	return inet6_ifla6_size();
5782 }
5783 
5784 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5785 			      u32 ext_filter_mask)
5786 {
5787 	struct inet6_dev *idev = __in6_dev_get(dev);
5788 
5789 	if (!idev)
5790 		return -ENODATA;
5791 
5792 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5793 		return -EMSGSIZE;
5794 
5795 	return 0;
5796 }
5797 
5798 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5799 			     struct netlink_ext_ack *extack)
5800 {
5801 	struct inet6_ifaddr *ifp;
5802 	struct net_device *dev = idev->dev;
5803 	bool clear_token, update_rs = false;
5804 	struct in6_addr ll_addr;
5805 
5806 	ASSERT_RTNL();
5807 
5808 	if (!token)
5809 		return -EINVAL;
5810 
5811 	if (dev->flags & IFF_LOOPBACK) {
5812 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5813 		return -EINVAL;
5814 	}
5815 
5816 	if (dev->flags & IFF_NOARP) {
5817 		NL_SET_ERR_MSG_MOD(extack,
5818 				   "Device does not do neighbour discovery");
5819 		return -EINVAL;
5820 	}
5821 
5822 	if (!ipv6_accept_ra(idev)) {
5823 		NL_SET_ERR_MSG_MOD(extack,
5824 				   "Router advertisement is disabled on device");
5825 		return -EINVAL;
5826 	}
5827 
5828 	if (idev->cnf.rtr_solicits == 0) {
5829 		NL_SET_ERR_MSG(extack,
5830 			       "Router solicitation is disabled on device");
5831 		return -EINVAL;
5832 	}
5833 
5834 	write_lock_bh(&idev->lock);
5835 
5836 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5837 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5838 
5839 	write_unlock_bh(&idev->lock);
5840 
5841 	clear_token = ipv6_addr_any(token);
5842 	if (clear_token)
5843 		goto update_lft;
5844 
5845 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5846 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5847 			     IFA_F_OPTIMISTIC)) {
5848 		/* If we're not ready, then normal ifup will take care
5849 		 * of this. Otherwise, we need to request our rs here.
5850 		 */
5851 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5852 		update_rs = true;
5853 	}
5854 
5855 update_lft:
5856 	write_lock_bh(&idev->lock);
5857 
5858 	if (update_rs) {
5859 		idev->if_flags |= IF_RS_SENT;
5860 		idev->rs_interval = rfc3315_s14_backoff_init(
5861 			idev->cnf.rtr_solicit_interval);
5862 		idev->rs_probes = 1;
5863 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5864 	}
5865 
5866 	/* Well, that's kinda nasty ... */
5867 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5868 		spin_lock(&ifp->lock);
5869 		if (ifp->tokenized) {
5870 			ifp->valid_lft = 0;
5871 			ifp->prefered_lft = 0;
5872 		}
5873 		spin_unlock(&ifp->lock);
5874 	}
5875 
5876 	write_unlock_bh(&idev->lock);
5877 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5878 	addrconf_verify_rtnl(dev_net(dev));
5879 	return 0;
5880 }
5881 
5882 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5883 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5884 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5885 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5886 					    .reject_message =
5887 						"IFLA_INET6_RA_MTU can not be set" },
5888 };
5889 
5890 static int check_addr_gen_mode(int mode)
5891 {
5892 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5893 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5894 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5895 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5896 		return -EINVAL;
5897 	return 1;
5898 }
5899 
5900 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5901 				int mode)
5902 {
5903 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5904 	    !idev->cnf.stable_secret.initialized &&
5905 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5906 		return -EINVAL;
5907 	return 1;
5908 }
5909 
5910 static int inet6_validate_link_af(const struct net_device *dev,
5911 				  const struct nlattr *nla,
5912 				  struct netlink_ext_ack *extack)
5913 {
5914 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5915 	struct inet6_dev *idev = NULL;
5916 	int err;
5917 
5918 	if (dev) {
5919 		idev = __in6_dev_get(dev);
5920 		if (!idev)
5921 			return -EAFNOSUPPORT;
5922 	}
5923 
5924 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5925 					  inet6_af_policy, extack);
5926 	if (err)
5927 		return err;
5928 
5929 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5930 		return -EINVAL;
5931 
5932 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5933 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5934 
5935 		if (check_addr_gen_mode(mode) < 0)
5936 			return -EINVAL;
5937 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5938 			return -EINVAL;
5939 	}
5940 
5941 	return 0;
5942 }
5943 
5944 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
5945 			     struct netlink_ext_ack *extack)
5946 {
5947 	struct inet6_dev *idev = __in6_dev_get(dev);
5948 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5949 	int err;
5950 
5951 	if (!idev)
5952 		return -EAFNOSUPPORT;
5953 
5954 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5955 		return -EINVAL;
5956 
5957 	if (tb[IFLA_INET6_TOKEN]) {
5958 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
5959 					extack);
5960 		if (err)
5961 			return err;
5962 	}
5963 
5964 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5965 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5966 
5967 		idev->cnf.addr_gen_mode = mode;
5968 	}
5969 
5970 	return 0;
5971 }
5972 
5973 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5974 			     u32 portid, u32 seq, int event, unsigned int flags)
5975 {
5976 	struct net_device *dev = idev->dev;
5977 	struct ifinfomsg *hdr;
5978 	struct nlmsghdr *nlh;
5979 	void *protoinfo;
5980 
5981 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5982 	if (!nlh)
5983 		return -EMSGSIZE;
5984 
5985 	hdr = nlmsg_data(nlh);
5986 	hdr->ifi_family = AF_INET6;
5987 	hdr->__ifi_pad = 0;
5988 	hdr->ifi_type = dev->type;
5989 	hdr->ifi_index = dev->ifindex;
5990 	hdr->ifi_flags = dev_get_flags(dev);
5991 	hdr->ifi_change = 0;
5992 
5993 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5994 	    (dev->addr_len &&
5995 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5996 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5997 	    (dev->ifindex != dev_get_iflink(dev) &&
5998 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5999 	    nla_put_u8(skb, IFLA_OPERSTATE,
6000 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
6001 		goto nla_put_failure;
6002 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6003 	if (!protoinfo)
6004 		goto nla_put_failure;
6005 
6006 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6007 		goto nla_put_failure;
6008 
6009 	nla_nest_end(skb, protoinfo);
6010 	nlmsg_end(skb, nlh);
6011 	return 0;
6012 
6013 nla_put_failure:
6014 	nlmsg_cancel(skb, nlh);
6015 	return -EMSGSIZE;
6016 }
6017 
6018 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6019 				   struct netlink_ext_ack *extack)
6020 {
6021 	struct ifinfomsg *ifm;
6022 
6023 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6024 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6025 		return -EINVAL;
6026 	}
6027 
6028 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6029 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6030 		return -EINVAL;
6031 	}
6032 
6033 	ifm = nlmsg_data(nlh);
6034 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6035 	    ifm->ifi_change || ifm->ifi_index) {
6036 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6037 		return -EINVAL;
6038 	}
6039 
6040 	return 0;
6041 }
6042 
6043 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6044 {
6045 	struct net *net = sock_net(skb->sk);
6046 	int h, s_h;
6047 	int idx = 0, s_idx;
6048 	struct net_device *dev;
6049 	struct inet6_dev *idev;
6050 	struct hlist_head *head;
6051 
6052 	/* only requests using strict checking can pass data to
6053 	 * influence the dump
6054 	 */
6055 	if (cb->strict_check) {
6056 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6057 
6058 		if (err < 0)
6059 			return err;
6060 	}
6061 
6062 	s_h = cb->args[0];
6063 	s_idx = cb->args[1];
6064 
6065 	rcu_read_lock();
6066 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
6067 		idx = 0;
6068 		head = &net->dev_index_head[h];
6069 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
6070 			if (idx < s_idx)
6071 				goto cont;
6072 			idev = __in6_dev_get(dev);
6073 			if (!idev)
6074 				goto cont;
6075 			if (inet6_fill_ifinfo(skb, idev,
6076 					      NETLINK_CB(cb->skb).portid,
6077 					      cb->nlh->nlmsg_seq,
6078 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
6079 				goto out;
6080 cont:
6081 			idx++;
6082 		}
6083 	}
6084 out:
6085 	rcu_read_unlock();
6086 	cb->args[1] = idx;
6087 	cb->args[0] = h;
6088 
6089 	return skb->len;
6090 }
6091 
6092 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6093 {
6094 	struct sk_buff *skb;
6095 	struct net *net = dev_net(idev->dev);
6096 	int err = -ENOBUFS;
6097 
6098 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6099 	if (!skb)
6100 		goto errout;
6101 
6102 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6103 	if (err < 0) {
6104 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6105 		WARN_ON(err == -EMSGSIZE);
6106 		kfree_skb(skb);
6107 		goto errout;
6108 	}
6109 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6110 	return;
6111 errout:
6112 	if (err < 0)
6113 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6114 }
6115 
6116 static inline size_t inet6_prefix_nlmsg_size(void)
6117 {
6118 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6119 	       + nla_total_size(sizeof(struct in6_addr))
6120 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6121 }
6122 
6123 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6124 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6125 			     int event, unsigned int flags)
6126 {
6127 	struct prefixmsg *pmsg;
6128 	struct nlmsghdr *nlh;
6129 	struct prefix_cacheinfo	ci;
6130 
6131 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6132 	if (!nlh)
6133 		return -EMSGSIZE;
6134 
6135 	pmsg = nlmsg_data(nlh);
6136 	pmsg->prefix_family = AF_INET6;
6137 	pmsg->prefix_pad1 = 0;
6138 	pmsg->prefix_pad2 = 0;
6139 	pmsg->prefix_ifindex = idev->dev->ifindex;
6140 	pmsg->prefix_len = pinfo->prefix_len;
6141 	pmsg->prefix_type = pinfo->type;
6142 	pmsg->prefix_pad3 = 0;
6143 	pmsg->prefix_flags = 0;
6144 	if (pinfo->onlink)
6145 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
6146 	if (pinfo->autoconf)
6147 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
6148 
6149 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6150 		goto nla_put_failure;
6151 	ci.preferred_time = ntohl(pinfo->prefered);
6152 	ci.valid_time = ntohl(pinfo->valid);
6153 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6154 		goto nla_put_failure;
6155 	nlmsg_end(skb, nlh);
6156 	return 0;
6157 
6158 nla_put_failure:
6159 	nlmsg_cancel(skb, nlh);
6160 	return -EMSGSIZE;
6161 }
6162 
6163 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6164 			 struct prefix_info *pinfo)
6165 {
6166 	struct sk_buff *skb;
6167 	struct net *net = dev_net(idev->dev);
6168 	int err = -ENOBUFS;
6169 
6170 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6171 	if (!skb)
6172 		goto errout;
6173 
6174 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6175 	if (err < 0) {
6176 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6177 		WARN_ON(err == -EMSGSIZE);
6178 		kfree_skb(skb);
6179 		goto errout;
6180 	}
6181 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6182 	return;
6183 errout:
6184 	if (err < 0)
6185 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6186 }
6187 
6188 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6189 {
6190 	struct net *net = dev_net(ifp->idev->dev);
6191 
6192 	if (event)
6193 		ASSERT_RTNL();
6194 
6195 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6196 
6197 	switch (event) {
6198 	case RTM_NEWADDR:
6199 		/*
6200 		 * If the address was optimistic we inserted the route at the
6201 		 * start of our DAD process, so we don't need to do it again.
6202 		 * If the device was taken down in the middle of the DAD
6203 		 * cycle there is a race where we could get here without a
6204 		 * host route, so nothing to insert. That will be fixed when
6205 		 * the device is brought up.
6206 		 */
6207 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6208 			ip6_ins_rt(net, ifp->rt);
6209 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6210 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6211 				&ifp->addr, ifp->idev->dev->name);
6212 		}
6213 
6214 		if (ifp->idev->cnf.forwarding)
6215 			addrconf_join_anycast(ifp);
6216 		if (!ipv6_addr_any(&ifp->peer_addr))
6217 			addrconf_prefix_route(&ifp->peer_addr, 128,
6218 					      ifp->rt_priority, ifp->idev->dev,
6219 					      0, 0, GFP_ATOMIC);
6220 		break;
6221 	case RTM_DELADDR:
6222 		if (ifp->idev->cnf.forwarding)
6223 			addrconf_leave_anycast(ifp);
6224 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6225 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6226 			struct fib6_info *rt;
6227 
6228 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6229 						       ifp->idev->dev, 0, 0,
6230 						       false);
6231 			if (rt)
6232 				ip6_del_rt(net, rt, false);
6233 		}
6234 		if (ifp->rt) {
6235 			ip6_del_rt(net, ifp->rt, false);
6236 			ifp->rt = NULL;
6237 		}
6238 		rt_genid_bump_ipv6(net);
6239 		break;
6240 	}
6241 	atomic_inc(&net->ipv6.dev_addr_genid);
6242 }
6243 
6244 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6245 {
6246 	if (likely(ifp->idev->dead == 0))
6247 		__ipv6_ifa_notify(event, ifp);
6248 }
6249 
6250 #ifdef CONFIG_SYSCTL
6251 
6252 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6253 		void *buffer, size_t *lenp, loff_t *ppos)
6254 {
6255 	int *valp = ctl->data;
6256 	int val = *valp;
6257 	loff_t pos = *ppos;
6258 	struct ctl_table lctl;
6259 	int ret;
6260 
6261 	/*
6262 	 * ctl->data points to idev->cnf.forwarding, we should
6263 	 * not modify it until we get the rtnl lock.
6264 	 */
6265 	lctl = *ctl;
6266 	lctl.data = &val;
6267 
6268 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6269 
6270 	if (write)
6271 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6272 	if (ret)
6273 		*ppos = pos;
6274 	return ret;
6275 }
6276 
6277 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6278 		void *buffer, size_t *lenp, loff_t *ppos)
6279 {
6280 	struct inet6_dev *idev = ctl->extra1;
6281 	int min_mtu = IPV6_MIN_MTU;
6282 	struct ctl_table lctl;
6283 
6284 	lctl = *ctl;
6285 	lctl.extra1 = &min_mtu;
6286 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6287 
6288 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6289 }
6290 
6291 static void dev_disable_change(struct inet6_dev *idev)
6292 {
6293 	struct netdev_notifier_info info;
6294 
6295 	if (!idev || !idev->dev)
6296 		return;
6297 
6298 	netdev_notifier_info_init(&info, idev->dev);
6299 	if (idev->cnf.disable_ipv6)
6300 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6301 	else
6302 		addrconf_notify(NULL, NETDEV_UP, &info);
6303 }
6304 
6305 static void addrconf_disable_change(struct net *net, __s32 newf)
6306 {
6307 	struct net_device *dev;
6308 	struct inet6_dev *idev;
6309 
6310 	for_each_netdev(net, dev) {
6311 		idev = __in6_dev_get(dev);
6312 		if (idev) {
6313 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6314 			idev->cnf.disable_ipv6 = newf;
6315 			if (changed)
6316 				dev_disable_change(idev);
6317 		}
6318 	}
6319 }
6320 
6321 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6322 {
6323 	struct net *net;
6324 	int old;
6325 
6326 	if (!rtnl_trylock())
6327 		return restart_syscall();
6328 
6329 	net = (struct net *)table->extra2;
6330 	old = *p;
6331 	*p = newf;
6332 
6333 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6334 		rtnl_unlock();
6335 		return 0;
6336 	}
6337 
6338 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6339 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6340 		addrconf_disable_change(net, newf);
6341 	} else if ((!newf) ^ (!old))
6342 		dev_disable_change((struct inet6_dev *)table->extra1);
6343 
6344 	rtnl_unlock();
6345 	return 0;
6346 }
6347 
6348 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6349 		void *buffer, size_t *lenp, loff_t *ppos)
6350 {
6351 	int *valp = ctl->data;
6352 	int val = *valp;
6353 	loff_t pos = *ppos;
6354 	struct ctl_table lctl;
6355 	int ret;
6356 
6357 	/*
6358 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6359 	 * not modify it until we get the rtnl lock.
6360 	 */
6361 	lctl = *ctl;
6362 	lctl.data = &val;
6363 
6364 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6365 
6366 	if (write)
6367 		ret = addrconf_disable_ipv6(ctl, valp, val);
6368 	if (ret)
6369 		*ppos = pos;
6370 	return ret;
6371 }
6372 
6373 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6374 		void *buffer, size_t *lenp, loff_t *ppos)
6375 {
6376 	int *valp = ctl->data;
6377 	int ret;
6378 	int old, new;
6379 
6380 	old = *valp;
6381 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6382 	new = *valp;
6383 
6384 	if (write && old != new) {
6385 		struct net *net = ctl->extra2;
6386 
6387 		if (!rtnl_trylock())
6388 			return restart_syscall();
6389 
6390 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6391 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6392 						     NETCONFA_PROXY_NEIGH,
6393 						     NETCONFA_IFINDEX_DEFAULT,
6394 						     net->ipv6.devconf_dflt);
6395 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6396 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6397 						     NETCONFA_PROXY_NEIGH,
6398 						     NETCONFA_IFINDEX_ALL,
6399 						     net->ipv6.devconf_all);
6400 		else {
6401 			struct inet6_dev *idev = ctl->extra1;
6402 
6403 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6404 						     NETCONFA_PROXY_NEIGH,
6405 						     idev->dev->ifindex,
6406 						     &idev->cnf);
6407 		}
6408 		rtnl_unlock();
6409 	}
6410 
6411 	return ret;
6412 }
6413 
6414 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6415 					 void *buffer, size_t *lenp,
6416 					 loff_t *ppos)
6417 {
6418 	int ret = 0;
6419 	u32 new_val;
6420 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6421 	struct net *net = (struct net *)ctl->extra2;
6422 	struct ctl_table tmp = {
6423 		.data = &new_val,
6424 		.maxlen = sizeof(new_val),
6425 		.mode = ctl->mode,
6426 	};
6427 
6428 	if (!rtnl_trylock())
6429 		return restart_syscall();
6430 
6431 	new_val = *((u32 *)ctl->data);
6432 
6433 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6434 	if (ret != 0)
6435 		goto out;
6436 
6437 	if (write) {
6438 		if (check_addr_gen_mode(new_val) < 0) {
6439 			ret = -EINVAL;
6440 			goto out;
6441 		}
6442 
6443 		if (idev) {
6444 			if (check_stable_privacy(idev, net, new_val) < 0) {
6445 				ret = -EINVAL;
6446 				goto out;
6447 			}
6448 
6449 			if (idev->cnf.addr_gen_mode != new_val) {
6450 				idev->cnf.addr_gen_mode = new_val;
6451 				addrconf_init_auto_addrs(idev->dev);
6452 			}
6453 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6454 			struct net_device *dev;
6455 
6456 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6457 			for_each_netdev(net, dev) {
6458 				idev = __in6_dev_get(dev);
6459 				if (idev &&
6460 				    idev->cnf.addr_gen_mode != new_val) {
6461 					idev->cnf.addr_gen_mode = new_val;
6462 					addrconf_init_auto_addrs(idev->dev);
6463 				}
6464 			}
6465 		}
6466 
6467 		*((u32 *)ctl->data) = new_val;
6468 	}
6469 
6470 out:
6471 	rtnl_unlock();
6472 
6473 	return ret;
6474 }
6475 
6476 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6477 					 void *buffer, size_t *lenp,
6478 					 loff_t *ppos)
6479 {
6480 	int err;
6481 	struct in6_addr addr;
6482 	char str[IPV6_MAX_STRLEN];
6483 	struct ctl_table lctl = *ctl;
6484 	struct net *net = ctl->extra2;
6485 	struct ipv6_stable_secret *secret = ctl->data;
6486 
6487 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6488 		return -EIO;
6489 
6490 	lctl.maxlen = IPV6_MAX_STRLEN;
6491 	lctl.data = str;
6492 
6493 	if (!rtnl_trylock())
6494 		return restart_syscall();
6495 
6496 	if (!write && !secret->initialized) {
6497 		err = -EIO;
6498 		goto out;
6499 	}
6500 
6501 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6502 	if (err >= sizeof(str)) {
6503 		err = -EIO;
6504 		goto out;
6505 	}
6506 
6507 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6508 	if (err || !write)
6509 		goto out;
6510 
6511 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6512 		err = -EIO;
6513 		goto out;
6514 	}
6515 
6516 	secret->initialized = true;
6517 	secret->secret = addr;
6518 
6519 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6520 		struct net_device *dev;
6521 
6522 		for_each_netdev(net, dev) {
6523 			struct inet6_dev *idev = __in6_dev_get(dev);
6524 
6525 			if (idev) {
6526 				idev->cnf.addr_gen_mode =
6527 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6528 			}
6529 		}
6530 	} else {
6531 		struct inet6_dev *idev = ctl->extra1;
6532 
6533 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6534 	}
6535 
6536 out:
6537 	rtnl_unlock();
6538 
6539 	return err;
6540 }
6541 
6542 static
6543 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6544 						int write, void *buffer,
6545 						size_t *lenp,
6546 						loff_t *ppos)
6547 {
6548 	int *valp = ctl->data;
6549 	int val = *valp;
6550 	loff_t pos = *ppos;
6551 	struct ctl_table lctl;
6552 	int ret;
6553 
6554 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6555 	 * we should not modify it until we get the rtnl lock.
6556 	 */
6557 	lctl = *ctl;
6558 	lctl.data = &val;
6559 
6560 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6561 
6562 	if (write)
6563 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6564 	if (ret)
6565 		*ppos = pos;
6566 	return ret;
6567 }
6568 
6569 static
6570 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6571 {
6572 	if (rt) {
6573 		if (action)
6574 			rt->dst.flags |= DST_NOPOLICY;
6575 		else
6576 			rt->dst.flags &= ~DST_NOPOLICY;
6577 	}
6578 }
6579 
6580 static
6581 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6582 {
6583 	struct inet6_ifaddr *ifa;
6584 
6585 	read_lock_bh(&idev->lock);
6586 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6587 		spin_lock(&ifa->lock);
6588 		if (ifa->rt) {
6589 			/* host routes only use builtin fib6_nh */
6590 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6591 			int cpu;
6592 
6593 			rcu_read_lock();
6594 			ifa->rt->dst_nopolicy = val ? true : false;
6595 			if (nh->rt6i_pcpu) {
6596 				for_each_possible_cpu(cpu) {
6597 					struct rt6_info **rtp;
6598 
6599 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6600 					addrconf_set_nopolicy(*rtp, val);
6601 				}
6602 			}
6603 			rcu_read_unlock();
6604 		}
6605 		spin_unlock(&ifa->lock);
6606 	}
6607 	read_unlock_bh(&idev->lock);
6608 }
6609 
6610 static
6611 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6612 {
6613 	struct inet6_dev *idev;
6614 	struct net *net;
6615 
6616 	if (!rtnl_trylock())
6617 		return restart_syscall();
6618 
6619 	*valp = val;
6620 
6621 	net = (struct net *)ctl->extra2;
6622 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6623 		rtnl_unlock();
6624 		return 0;
6625 	}
6626 
6627 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6628 		struct net_device *dev;
6629 
6630 		for_each_netdev(net, dev) {
6631 			idev = __in6_dev_get(dev);
6632 			if (idev)
6633 				addrconf_disable_policy_idev(idev, val);
6634 		}
6635 	} else {
6636 		idev = (struct inet6_dev *)ctl->extra1;
6637 		addrconf_disable_policy_idev(idev, val);
6638 	}
6639 
6640 	rtnl_unlock();
6641 	return 0;
6642 }
6643 
6644 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6645 				   void *buffer, size_t *lenp, loff_t *ppos)
6646 {
6647 	int *valp = ctl->data;
6648 	int val = *valp;
6649 	loff_t pos = *ppos;
6650 	struct ctl_table lctl;
6651 	int ret;
6652 
6653 	lctl = *ctl;
6654 	lctl.data = &val;
6655 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6656 
6657 	if (write && (*valp != val))
6658 		ret = addrconf_disable_policy(ctl, valp, val);
6659 
6660 	if (ret)
6661 		*ppos = pos;
6662 
6663 	return ret;
6664 }
6665 
6666 static int minus_one = -1;
6667 static const int two_five_five = 255;
6668 static u32 ioam6_if_id_max = U16_MAX;
6669 
6670 static const struct ctl_table addrconf_sysctl[] = {
6671 	{
6672 		.procname	= "forwarding",
6673 		.data		= &ipv6_devconf.forwarding,
6674 		.maxlen		= sizeof(int),
6675 		.mode		= 0644,
6676 		.proc_handler	= addrconf_sysctl_forward,
6677 	},
6678 	{
6679 		.procname	= "hop_limit",
6680 		.data		= &ipv6_devconf.hop_limit,
6681 		.maxlen		= sizeof(int),
6682 		.mode		= 0644,
6683 		.proc_handler	= proc_dointvec_minmax,
6684 		.extra1		= (void *)SYSCTL_ONE,
6685 		.extra2		= (void *)&two_five_five,
6686 	},
6687 	{
6688 		.procname	= "mtu",
6689 		.data		= &ipv6_devconf.mtu6,
6690 		.maxlen		= sizeof(int),
6691 		.mode		= 0644,
6692 		.proc_handler	= addrconf_sysctl_mtu,
6693 	},
6694 	{
6695 		.procname	= "accept_ra",
6696 		.data		= &ipv6_devconf.accept_ra,
6697 		.maxlen		= sizeof(int),
6698 		.mode		= 0644,
6699 		.proc_handler	= proc_dointvec,
6700 	},
6701 	{
6702 		.procname	= "accept_redirects",
6703 		.data		= &ipv6_devconf.accept_redirects,
6704 		.maxlen		= sizeof(int),
6705 		.mode		= 0644,
6706 		.proc_handler	= proc_dointvec,
6707 	},
6708 	{
6709 		.procname	= "autoconf",
6710 		.data		= &ipv6_devconf.autoconf,
6711 		.maxlen		= sizeof(int),
6712 		.mode		= 0644,
6713 		.proc_handler	= proc_dointvec,
6714 	},
6715 	{
6716 		.procname	= "dad_transmits",
6717 		.data		= &ipv6_devconf.dad_transmits,
6718 		.maxlen		= sizeof(int),
6719 		.mode		= 0644,
6720 		.proc_handler	= proc_dointvec,
6721 	},
6722 	{
6723 		.procname	= "router_solicitations",
6724 		.data		= &ipv6_devconf.rtr_solicits,
6725 		.maxlen		= sizeof(int),
6726 		.mode		= 0644,
6727 		.proc_handler	= proc_dointvec_minmax,
6728 		.extra1		= &minus_one,
6729 	},
6730 	{
6731 		.procname	= "router_solicitation_interval",
6732 		.data		= &ipv6_devconf.rtr_solicit_interval,
6733 		.maxlen		= sizeof(int),
6734 		.mode		= 0644,
6735 		.proc_handler	= proc_dointvec_jiffies,
6736 	},
6737 	{
6738 		.procname	= "router_solicitation_max_interval",
6739 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6740 		.maxlen		= sizeof(int),
6741 		.mode		= 0644,
6742 		.proc_handler	= proc_dointvec_jiffies,
6743 	},
6744 	{
6745 		.procname	= "router_solicitation_delay",
6746 		.data		= &ipv6_devconf.rtr_solicit_delay,
6747 		.maxlen		= sizeof(int),
6748 		.mode		= 0644,
6749 		.proc_handler	= proc_dointvec_jiffies,
6750 	},
6751 	{
6752 		.procname	= "force_mld_version",
6753 		.data		= &ipv6_devconf.force_mld_version,
6754 		.maxlen		= sizeof(int),
6755 		.mode		= 0644,
6756 		.proc_handler	= proc_dointvec,
6757 	},
6758 	{
6759 		.procname	= "mldv1_unsolicited_report_interval",
6760 		.data		=
6761 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6762 		.maxlen		= sizeof(int),
6763 		.mode		= 0644,
6764 		.proc_handler	= proc_dointvec_ms_jiffies,
6765 	},
6766 	{
6767 		.procname	= "mldv2_unsolicited_report_interval",
6768 		.data		=
6769 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6770 		.maxlen		= sizeof(int),
6771 		.mode		= 0644,
6772 		.proc_handler	= proc_dointvec_ms_jiffies,
6773 	},
6774 	{
6775 		.procname	= "use_tempaddr",
6776 		.data		= &ipv6_devconf.use_tempaddr,
6777 		.maxlen		= sizeof(int),
6778 		.mode		= 0644,
6779 		.proc_handler	= proc_dointvec,
6780 	},
6781 	{
6782 		.procname	= "temp_valid_lft",
6783 		.data		= &ipv6_devconf.temp_valid_lft,
6784 		.maxlen		= sizeof(int),
6785 		.mode		= 0644,
6786 		.proc_handler	= proc_dointvec,
6787 	},
6788 	{
6789 		.procname	= "temp_prefered_lft",
6790 		.data		= &ipv6_devconf.temp_prefered_lft,
6791 		.maxlen		= sizeof(int),
6792 		.mode		= 0644,
6793 		.proc_handler	= proc_dointvec,
6794 	},
6795 	{
6796 		.procname	= "regen_max_retry",
6797 		.data		= &ipv6_devconf.regen_max_retry,
6798 		.maxlen		= sizeof(int),
6799 		.mode		= 0644,
6800 		.proc_handler	= proc_dointvec,
6801 	},
6802 	{
6803 		.procname	= "max_desync_factor",
6804 		.data		= &ipv6_devconf.max_desync_factor,
6805 		.maxlen		= sizeof(int),
6806 		.mode		= 0644,
6807 		.proc_handler	= proc_dointvec,
6808 	},
6809 	{
6810 		.procname	= "max_addresses",
6811 		.data		= &ipv6_devconf.max_addresses,
6812 		.maxlen		= sizeof(int),
6813 		.mode		= 0644,
6814 		.proc_handler	= proc_dointvec,
6815 	},
6816 	{
6817 		.procname	= "accept_ra_defrtr",
6818 		.data		= &ipv6_devconf.accept_ra_defrtr,
6819 		.maxlen		= sizeof(int),
6820 		.mode		= 0644,
6821 		.proc_handler	= proc_dointvec,
6822 	},
6823 	{
6824 		.procname	= "ra_defrtr_metric",
6825 		.data		= &ipv6_devconf.ra_defrtr_metric,
6826 		.maxlen		= sizeof(u32),
6827 		.mode		= 0644,
6828 		.proc_handler	= proc_douintvec_minmax,
6829 		.extra1		= (void *)SYSCTL_ONE,
6830 	},
6831 	{
6832 		.procname	= "accept_ra_min_hop_limit",
6833 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6834 		.maxlen		= sizeof(int),
6835 		.mode		= 0644,
6836 		.proc_handler	= proc_dointvec,
6837 	},
6838 	{
6839 		.procname	= "accept_ra_min_lft",
6840 		.data		= &ipv6_devconf.accept_ra_min_lft,
6841 		.maxlen		= sizeof(int),
6842 		.mode		= 0644,
6843 		.proc_handler	= proc_dointvec,
6844 	},
6845 	{
6846 		.procname	= "accept_ra_pinfo",
6847 		.data		= &ipv6_devconf.accept_ra_pinfo,
6848 		.maxlen		= sizeof(int),
6849 		.mode		= 0644,
6850 		.proc_handler	= proc_dointvec,
6851 	},
6852 	{
6853 		.procname	= "ra_honor_pio_life",
6854 		.data		= &ipv6_devconf.ra_honor_pio_life,
6855 		.maxlen		= sizeof(u8),
6856 		.mode		= 0644,
6857 		.proc_handler	= proc_dou8vec_minmax,
6858 		.extra1		= SYSCTL_ZERO,
6859 		.extra2		= SYSCTL_ONE,
6860 	},
6861 #ifdef CONFIG_IPV6_ROUTER_PREF
6862 	{
6863 		.procname	= "accept_ra_rtr_pref",
6864 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6865 		.maxlen		= sizeof(int),
6866 		.mode		= 0644,
6867 		.proc_handler	= proc_dointvec,
6868 	},
6869 	{
6870 		.procname	= "router_probe_interval",
6871 		.data		= &ipv6_devconf.rtr_probe_interval,
6872 		.maxlen		= sizeof(int),
6873 		.mode		= 0644,
6874 		.proc_handler	= proc_dointvec_jiffies,
6875 	},
6876 #ifdef CONFIG_IPV6_ROUTE_INFO
6877 	{
6878 		.procname	= "accept_ra_rt_info_min_plen",
6879 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6880 		.maxlen		= sizeof(int),
6881 		.mode		= 0644,
6882 		.proc_handler	= proc_dointvec,
6883 	},
6884 	{
6885 		.procname	= "accept_ra_rt_info_max_plen",
6886 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6887 		.maxlen		= sizeof(int),
6888 		.mode		= 0644,
6889 		.proc_handler	= proc_dointvec,
6890 	},
6891 #endif
6892 #endif
6893 	{
6894 		.procname	= "proxy_ndp",
6895 		.data		= &ipv6_devconf.proxy_ndp,
6896 		.maxlen		= sizeof(int),
6897 		.mode		= 0644,
6898 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6899 	},
6900 	{
6901 		.procname	= "accept_source_route",
6902 		.data		= &ipv6_devconf.accept_source_route,
6903 		.maxlen		= sizeof(int),
6904 		.mode		= 0644,
6905 		.proc_handler	= proc_dointvec,
6906 	},
6907 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6908 	{
6909 		.procname	= "optimistic_dad",
6910 		.data		= &ipv6_devconf.optimistic_dad,
6911 		.maxlen		= sizeof(int),
6912 		.mode		= 0644,
6913 		.proc_handler   = proc_dointvec,
6914 	},
6915 	{
6916 		.procname	= "use_optimistic",
6917 		.data		= &ipv6_devconf.use_optimistic,
6918 		.maxlen		= sizeof(int),
6919 		.mode		= 0644,
6920 		.proc_handler	= proc_dointvec,
6921 	},
6922 #endif
6923 #ifdef CONFIG_IPV6_MROUTE
6924 	{
6925 		.procname	= "mc_forwarding",
6926 		.data		= &ipv6_devconf.mc_forwarding,
6927 		.maxlen		= sizeof(int),
6928 		.mode		= 0444,
6929 		.proc_handler	= proc_dointvec,
6930 	},
6931 #endif
6932 	{
6933 		.procname	= "disable_ipv6",
6934 		.data		= &ipv6_devconf.disable_ipv6,
6935 		.maxlen		= sizeof(int),
6936 		.mode		= 0644,
6937 		.proc_handler	= addrconf_sysctl_disable,
6938 	},
6939 	{
6940 		.procname	= "accept_dad",
6941 		.data		= &ipv6_devconf.accept_dad,
6942 		.maxlen		= sizeof(int),
6943 		.mode		= 0644,
6944 		.proc_handler	= proc_dointvec,
6945 	},
6946 	{
6947 		.procname	= "force_tllao",
6948 		.data		= &ipv6_devconf.force_tllao,
6949 		.maxlen		= sizeof(int),
6950 		.mode		= 0644,
6951 		.proc_handler	= proc_dointvec
6952 	},
6953 	{
6954 		.procname	= "ndisc_notify",
6955 		.data		= &ipv6_devconf.ndisc_notify,
6956 		.maxlen		= sizeof(int),
6957 		.mode		= 0644,
6958 		.proc_handler	= proc_dointvec
6959 	},
6960 	{
6961 		.procname	= "suppress_frag_ndisc",
6962 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6963 		.maxlen		= sizeof(int),
6964 		.mode		= 0644,
6965 		.proc_handler	= proc_dointvec
6966 	},
6967 	{
6968 		.procname	= "accept_ra_from_local",
6969 		.data		= &ipv6_devconf.accept_ra_from_local,
6970 		.maxlen		= sizeof(int),
6971 		.mode		= 0644,
6972 		.proc_handler	= proc_dointvec,
6973 	},
6974 	{
6975 		.procname	= "accept_ra_mtu",
6976 		.data		= &ipv6_devconf.accept_ra_mtu,
6977 		.maxlen		= sizeof(int),
6978 		.mode		= 0644,
6979 		.proc_handler	= proc_dointvec,
6980 	},
6981 	{
6982 		.procname	= "stable_secret",
6983 		.data		= &ipv6_devconf.stable_secret,
6984 		.maxlen		= IPV6_MAX_STRLEN,
6985 		.mode		= 0600,
6986 		.proc_handler	= addrconf_sysctl_stable_secret,
6987 	},
6988 	{
6989 		.procname	= "use_oif_addrs_only",
6990 		.data		= &ipv6_devconf.use_oif_addrs_only,
6991 		.maxlen		= sizeof(int),
6992 		.mode		= 0644,
6993 		.proc_handler	= proc_dointvec,
6994 	},
6995 	{
6996 		.procname	= "ignore_routes_with_linkdown",
6997 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6998 		.maxlen		= sizeof(int),
6999 		.mode		= 0644,
7000 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7001 	},
7002 	{
7003 		.procname	= "drop_unicast_in_l2_multicast",
7004 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7005 		.maxlen		= sizeof(int),
7006 		.mode		= 0644,
7007 		.proc_handler	= proc_dointvec,
7008 	},
7009 	{
7010 		.procname	= "drop_unsolicited_na",
7011 		.data		= &ipv6_devconf.drop_unsolicited_na,
7012 		.maxlen		= sizeof(int),
7013 		.mode		= 0644,
7014 		.proc_handler	= proc_dointvec,
7015 	},
7016 	{
7017 		.procname	= "keep_addr_on_down",
7018 		.data		= &ipv6_devconf.keep_addr_on_down,
7019 		.maxlen		= sizeof(int),
7020 		.mode		= 0644,
7021 		.proc_handler	= proc_dointvec,
7022 
7023 	},
7024 	{
7025 		.procname	= "seg6_enabled",
7026 		.data		= &ipv6_devconf.seg6_enabled,
7027 		.maxlen		= sizeof(int),
7028 		.mode		= 0644,
7029 		.proc_handler	= proc_dointvec,
7030 	},
7031 #ifdef CONFIG_IPV6_SEG6_HMAC
7032 	{
7033 		.procname	= "seg6_require_hmac",
7034 		.data		= &ipv6_devconf.seg6_require_hmac,
7035 		.maxlen		= sizeof(int),
7036 		.mode		= 0644,
7037 		.proc_handler	= proc_dointvec,
7038 	},
7039 #endif
7040 	{
7041 		.procname       = "enhanced_dad",
7042 		.data           = &ipv6_devconf.enhanced_dad,
7043 		.maxlen         = sizeof(int),
7044 		.mode           = 0644,
7045 		.proc_handler   = proc_dointvec,
7046 	},
7047 	{
7048 		.procname	= "addr_gen_mode",
7049 		.data		= &ipv6_devconf.addr_gen_mode,
7050 		.maxlen		= sizeof(int),
7051 		.mode		= 0644,
7052 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7053 	},
7054 	{
7055 		.procname       = "disable_policy",
7056 		.data           = &ipv6_devconf.disable_policy,
7057 		.maxlen         = sizeof(int),
7058 		.mode           = 0644,
7059 		.proc_handler   = addrconf_sysctl_disable_policy,
7060 	},
7061 	{
7062 		.procname	= "ndisc_tclass",
7063 		.data		= &ipv6_devconf.ndisc_tclass,
7064 		.maxlen		= sizeof(int),
7065 		.mode		= 0644,
7066 		.proc_handler	= proc_dointvec_minmax,
7067 		.extra1		= (void *)SYSCTL_ZERO,
7068 		.extra2		= (void *)&two_five_five,
7069 	},
7070 	{
7071 		.procname	= "rpl_seg_enabled",
7072 		.data		= &ipv6_devconf.rpl_seg_enabled,
7073 		.maxlen		= sizeof(int),
7074 		.mode		= 0644,
7075 		.proc_handler	= proc_dointvec,
7076 	},
7077 	{
7078 		.procname	= "ioam6_enabled",
7079 		.data		= &ipv6_devconf.ioam6_enabled,
7080 		.maxlen		= sizeof(u8),
7081 		.mode		= 0644,
7082 		.proc_handler	= proc_dou8vec_minmax,
7083 		.extra1		= (void *)SYSCTL_ZERO,
7084 		.extra2		= (void *)SYSCTL_ONE,
7085 	},
7086 	{
7087 		.procname	= "ioam6_id",
7088 		.data		= &ipv6_devconf.ioam6_id,
7089 		.maxlen		= sizeof(u32),
7090 		.mode		= 0644,
7091 		.proc_handler	= proc_douintvec_minmax,
7092 		.extra1		= (void *)SYSCTL_ZERO,
7093 		.extra2		= (void *)&ioam6_if_id_max,
7094 	},
7095 	{
7096 		.procname	= "ioam6_id_wide",
7097 		.data		= &ipv6_devconf.ioam6_id_wide,
7098 		.maxlen		= sizeof(u32),
7099 		.mode		= 0644,
7100 		.proc_handler	= proc_douintvec,
7101 	},
7102 	{
7103 		.procname	= "ndisc_evict_nocarrier",
7104 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7105 		.maxlen		= sizeof(u8),
7106 		.mode		= 0644,
7107 		.proc_handler	= proc_dou8vec_minmax,
7108 		.extra1		= (void *)SYSCTL_ZERO,
7109 		.extra2		= (void *)SYSCTL_ONE,
7110 	},
7111 	{
7112 		.procname	= "accept_untracked_na",
7113 		.data		= &ipv6_devconf.accept_untracked_na,
7114 		.maxlen		= sizeof(int),
7115 		.mode		= 0644,
7116 		.proc_handler	= proc_dointvec_minmax,
7117 		.extra1		= SYSCTL_ZERO,
7118 		.extra2		= SYSCTL_TWO,
7119 	},
7120 	{
7121 		/* sentinel */
7122 	}
7123 };
7124 
7125 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7126 		struct inet6_dev *idev, struct ipv6_devconf *p)
7127 {
7128 	int i, ifindex;
7129 	struct ctl_table *table;
7130 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7131 
7132 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7133 	if (!table)
7134 		goto out;
7135 
7136 	for (i = 0; table[i].data; i++) {
7137 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7138 		/* If one of these is already set, then it is not safe to
7139 		 * overwrite either of them: this makes proc_dointvec_minmax
7140 		 * usable.
7141 		 */
7142 		if (!table[i].extra1 && !table[i].extra2) {
7143 			table[i].extra1 = idev; /* embedded; no ref */
7144 			table[i].extra2 = net;
7145 		}
7146 	}
7147 
7148 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7149 
7150 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7151 						  ARRAY_SIZE(addrconf_sysctl));
7152 	if (!p->sysctl_header)
7153 		goto free;
7154 
7155 	if (!strcmp(dev_name, "all"))
7156 		ifindex = NETCONFA_IFINDEX_ALL;
7157 	else if (!strcmp(dev_name, "default"))
7158 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7159 	else
7160 		ifindex = idev->dev->ifindex;
7161 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7162 				     ifindex, p);
7163 	return 0;
7164 
7165 free:
7166 	kfree(table);
7167 out:
7168 	return -ENOBUFS;
7169 }
7170 
7171 static void __addrconf_sysctl_unregister(struct net *net,
7172 					 struct ipv6_devconf *p, int ifindex)
7173 {
7174 	struct ctl_table *table;
7175 
7176 	if (!p->sysctl_header)
7177 		return;
7178 
7179 	table = p->sysctl_header->ctl_table_arg;
7180 	unregister_net_sysctl_table(p->sysctl_header);
7181 	p->sysctl_header = NULL;
7182 	kfree(table);
7183 
7184 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7185 }
7186 
7187 static int addrconf_sysctl_register(struct inet6_dev *idev)
7188 {
7189 	int err;
7190 
7191 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7192 		return -EINVAL;
7193 
7194 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7195 				    &ndisc_ifinfo_sysctl_change);
7196 	if (err)
7197 		return err;
7198 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7199 					 idev, &idev->cnf);
7200 	if (err)
7201 		neigh_sysctl_unregister(idev->nd_parms);
7202 
7203 	return err;
7204 }
7205 
7206 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7207 {
7208 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7209 				     idev->dev->ifindex);
7210 	neigh_sysctl_unregister(idev->nd_parms);
7211 }
7212 
7213 
7214 #endif
7215 
7216 static int __net_init addrconf_init_net(struct net *net)
7217 {
7218 	int err = -ENOMEM;
7219 	struct ipv6_devconf *all, *dflt;
7220 
7221 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7222 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7223 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7224 					   sizeof(struct hlist_head),
7225 					   GFP_KERNEL);
7226 	if (!net->ipv6.inet6_addr_lst)
7227 		goto err_alloc_addr;
7228 
7229 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7230 	if (!all)
7231 		goto err_alloc_all;
7232 
7233 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7234 	if (!dflt)
7235 		goto err_alloc_dflt;
7236 
7237 	if (!net_eq(net, &init_net)) {
7238 		switch (net_inherit_devconf()) {
7239 		case 1:  /* copy from init_net */
7240 			memcpy(all, init_net.ipv6.devconf_all,
7241 			       sizeof(ipv6_devconf));
7242 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7243 			       sizeof(ipv6_devconf_dflt));
7244 			break;
7245 		case 3: /* copy from the current netns */
7246 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7247 			       sizeof(ipv6_devconf));
7248 			memcpy(dflt,
7249 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7250 			       sizeof(ipv6_devconf_dflt));
7251 			break;
7252 		case 0:
7253 		case 2:
7254 			/* use compiled values */
7255 			break;
7256 		}
7257 	}
7258 
7259 	/* these will be inherited by all namespaces */
7260 	dflt->autoconf = ipv6_defaults.autoconf;
7261 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7262 
7263 	dflt->stable_secret.initialized = false;
7264 	all->stable_secret.initialized = false;
7265 
7266 	net->ipv6.devconf_all = all;
7267 	net->ipv6.devconf_dflt = dflt;
7268 
7269 #ifdef CONFIG_SYSCTL
7270 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7271 	if (err < 0)
7272 		goto err_reg_all;
7273 
7274 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7275 	if (err < 0)
7276 		goto err_reg_dflt;
7277 #endif
7278 	return 0;
7279 
7280 #ifdef CONFIG_SYSCTL
7281 err_reg_dflt:
7282 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7283 err_reg_all:
7284 	kfree(dflt);
7285 	net->ipv6.devconf_dflt = NULL;
7286 #endif
7287 err_alloc_dflt:
7288 	kfree(all);
7289 	net->ipv6.devconf_all = NULL;
7290 err_alloc_all:
7291 	kfree(net->ipv6.inet6_addr_lst);
7292 err_alloc_addr:
7293 	return err;
7294 }
7295 
7296 static void __net_exit addrconf_exit_net(struct net *net)
7297 {
7298 	int i;
7299 
7300 #ifdef CONFIG_SYSCTL
7301 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7302 				     NETCONFA_IFINDEX_DEFAULT);
7303 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7304 				     NETCONFA_IFINDEX_ALL);
7305 #endif
7306 	kfree(net->ipv6.devconf_dflt);
7307 	net->ipv6.devconf_dflt = NULL;
7308 	kfree(net->ipv6.devconf_all);
7309 	net->ipv6.devconf_all = NULL;
7310 
7311 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7312 	/*
7313 	 *	Check hash table, then free it.
7314 	 */
7315 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7316 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7317 
7318 	kfree(net->ipv6.inet6_addr_lst);
7319 	net->ipv6.inet6_addr_lst = NULL;
7320 }
7321 
7322 static struct pernet_operations addrconf_ops = {
7323 	.init = addrconf_init_net,
7324 	.exit = addrconf_exit_net,
7325 };
7326 
7327 static struct rtnl_af_ops inet6_ops __read_mostly = {
7328 	.family		  = AF_INET6,
7329 	.fill_link_af	  = inet6_fill_link_af,
7330 	.get_link_af_size = inet6_get_link_af_size,
7331 	.validate_link_af = inet6_validate_link_af,
7332 	.set_link_af	  = inet6_set_link_af,
7333 };
7334 
7335 /*
7336  *	Init / cleanup code
7337  */
7338 
7339 int __init addrconf_init(void)
7340 {
7341 	struct inet6_dev *idev;
7342 	int err;
7343 
7344 	err = ipv6_addr_label_init();
7345 	if (err < 0) {
7346 		pr_crit("%s: cannot initialize default policy table: %d\n",
7347 			__func__, err);
7348 		goto out;
7349 	}
7350 
7351 	err = register_pernet_subsys(&addrconf_ops);
7352 	if (err < 0)
7353 		goto out_addrlabel;
7354 
7355 	addrconf_wq = create_workqueue("ipv6_addrconf");
7356 	if (!addrconf_wq) {
7357 		err = -ENOMEM;
7358 		goto out_nowq;
7359 	}
7360 
7361 	rtnl_lock();
7362 	idev = ipv6_add_dev(blackhole_netdev);
7363 	rtnl_unlock();
7364 	if (IS_ERR(idev)) {
7365 		err = PTR_ERR(idev);
7366 		goto errlo;
7367 	}
7368 
7369 	ip6_route_init_special_entries();
7370 
7371 	register_netdevice_notifier(&ipv6_dev_notf);
7372 
7373 	addrconf_verify(&init_net);
7374 
7375 	rtnl_af_register(&inet6_ops);
7376 
7377 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7378 				   NULL, inet6_dump_ifinfo, 0);
7379 	if (err < 0)
7380 		goto errout;
7381 
7382 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7383 				   inet6_rtm_newaddr, NULL, 0);
7384 	if (err < 0)
7385 		goto errout;
7386 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7387 				   inet6_rtm_deladdr, NULL, 0);
7388 	if (err < 0)
7389 		goto errout;
7390 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7391 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7392 				   RTNL_FLAG_DOIT_UNLOCKED);
7393 	if (err < 0)
7394 		goto errout;
7395 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7396 				   NULL, inet6_dump_ifmcaddr, 0);
7397 	if (err < 0)
7398 		goto errout;
7399 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7400 				   NULL, inet6_dump_ifacaddr, 0);
7401 	if (err < 0)
7402 		goto errout;
7403 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7404 				   inet6_netconf_get_devconf,
7405 				   inet6_netconf_dump_devconf,
7406 				   RTNL_FLAG_DOIT_UNLOCKED);
7407 	if (err < 0)
7408 		goto errout;
7409 	err = ipv6_addr_label_rtnl_register();
7410 	if (err < 0)
7411 		goto errout;
7412 
7413 	return 0;
7414 errout:
7415 	rtnl_unregister_all(PF_INET6);
7416 	rtnl_af_unregister(&inet6_ops);
7417 	unregister_netdevice_notifier(&ipv6_dev_notf);
7418 errlo:
7419 	destroy_workqueue(addrconf_wq);
7420 out_nowq:
7421 	unregister_pernet_subsys(&addrconf_ops);
7422 out_addrlabel:
7423 	ipv6_addr_label_cleanup();
7424 out:
7425 	return err;
7426 }
7427 
7428 void addrconf_cleanup(void)
7429 {
7430 	struct net_device *dev;
7431 
7432 	unregister_netdevice_notifier(&ipv6_dev_notf);
7433 	unregister_pernet_subsys(&addrconf_ops);
7434 	ipv6_addr_label_cleanup();
7435 
7436 	rtnl_af_unregister(&inet6_ops);
7437 
7438 	rtnl_lock();
7439 
7440 	/* clean dev list */
7441 	for_each_netdev(&init_net, dev) {
7442 		if (__in6_dev_get(dev) == NULL)
7443 			continue;
7444 		addrconf_ifdown(dev, true);
7445 	}
7446 	addrconf_ifdown(init_net.loopback_dev, true);
7447 
7448 	rtnl_unlock();
7449 
7450 	destroy_workqueue(addrconf_wq);
7451 }
7452